Acute and sub-lethal exposure to copper oxide nanoparticles causes oxidative stress and teratogenicity in zebrafish embryos.

PubMed

Ganesan, Santhanamari; Anaimalai Thirumurthi, Naveenkumar; Raghunath, Azhwar; Vijayakumar, Savitha; Perumal, Ekambaram

2016-04-01

Nano-copper oxides are a versatile inorganic material. As a result of their versatility, the immense applications and usage end up in the environment causing a concern for the lifespan of various beings. The ambiguities surround globally on the toxic effects of copper oxide nanoparticles (CuO-NPs). Hence, the present study endeavored to study the sub-lethal acute exposure effects on the developing zebrafish embryos. The 48 hpf LC50 value was about 64 ppm. Therefore, we have chosen the sub-lethal dose of 40 and 60 ppm for the study. Accumulation of CuO-NPs was evidenced from the SEM-EDS and AAS analyzes. The alterations in the AChE and Na(+)/K(+)-ATPase activities disrupted the development process. An increment in the levels of oxidants with a concomitant decrease in the antioxidant enzymes confirmed the induction of oxidative stress. Oxidative stress triggered apoptosis in the exposed embryos. Developmental anomalies were observed with CuO-NPs exposure in addition to oxidative stress in the developing embryos. Decreased heart rate and hatching delay hindered the normal developmental processes. Our work has offered valuable data on the connection between oxidative stress and teratogenicity leading to lethality caused by CuO-NPs. A further molecular mechanism unraveling the uncharted connection between oxidative stress and teratogenicity will aid in the safe use of CuO-NPs. Copyright © 2015 John Wiley & Sons, Ltd.

Lethal effect of dehydroleucodine (DhL) on amphibian Bufo arenarum embryos.

PubMed

Moreno, Liliana Elizabeth; Juárez, Américo Osvaldo; Pelzer, Lilian Eugenia

2012-03-01

The dehydroleucodine is a sesquiterpene lactone isolated from Artemisia douglasiana Besser which is used in popular medicine. Toxicity tests using embryos of amphibian have been widely used in order to predict toxic effects of different compounds. However, to our knowledge, there are not studies focussed on the toxic effects of dehydroleucodine on Bufo arenarum, which is an anuran widely distributed in South America. The effect of dehydroleucodine on the survival of embryos was evaluated in an acute test during the early life stage of B. arenarum embryos. Lethality and the degree of adverse effects were dehydroleucodine dose-dependent. Overall, amphibian early life stages appeared to be more susceptible to the embryotoxicity associated with exposure to dehydroleucodine, especially at concentration greater that 3mM. This increased susceptibility may result from the relatively high rate of cellular differentiation and morphogenesis that occurs at this early stage of development. Copyright © 2012 Elsevier Ltd. All rights reserved.

Assessment of Jatropha curcas L. biodiesel seed cake toxicity using the zebrafish (Danio rerio) embryo toxicity (ZFET) test.

PubMed

Hallare, Arnold V; Ruiz, Paulo Lorenzo S; Cariño, J C Earl D

2014-05-01

Consequent to the growing demand for alternative sources of energy, the seeds from Jatropha curcas remain to be the favorite for biodiesel production. However, a significant volume of the residual organic mass (seed cake) is produced during the extraction process, which raises concerns on safe waste disposal. In the present study, we assessed the toxicity of J. curcas seed cake using the zebrafish (Danio rerio) embryotoxicity test. Within 1-h post-fertilization (hpf), the fertilized eggs were exposed to five mass concentrations of J. curcas seed cake and were followed through 24, 48, and 72 hpf. Toxicity was evaluated based on lethal endpoints induced on zebrafish embryos namely egg coagulation, non-formation of somites, and non-detachment of tail. The lowest concentration tested, 1 g/L, was not able to elicit toxicity on embryos whereas 100 % mortality (based also on lethal endpoints) was recorded at the highest concentration at 2.15 g/L. The computed LC50 for the J. curcas seed cake was 1.61 g/L. No further increase in mortality was observed in the succeeding time points (48 and 72 hpf) indicating that J. curcas seed cake exerted acute toxicity on zebrafish embryos. Sublethal endpoints (yolk sac and pericardial edema) were noted at 72 hpf in zebrafish embryos exposed to higher concentrations. The observed lethal endpoints induced on zebrafish embryos were discussed in relation to the active principles, notably, phorbol esters that have remained in the seed cake even after extraction.

The Orphan Disease Networks

PubMed Central

Zhang, Minlu; Zhu, Cheng; Jacomy, Alexis; Lu, Long J.; Jegga, Anil G.

2011-01-01

The low prevalence rate of orphan diseases (OD) requires special combined efforts to improve diagnosis, prevention, and discovery of novel therapeutic strategies. To identify and investigate relationships based on shared genes or shared functional features, we have conducted a bioinformatic-based global analysis of all orphan diseases with known disease-causing mutant genes. Starting with a bipartite network of known OD and OD-causing mutant genes and using the human protein interactome, we first construct and topologically analyze three networks: the orphan disease network, the orphan disease-causing mutant gene network, and the orphan disease-causing mutant gene interactome. Our results demonstrate that in contrast to the common disease-causing mutant genes that are predominantly nonessential, a majority of orphan disease-causing mutant genes are essential. In confirmation of this finding, we found that OD-causing mutant genes are topologically important in the protein interactome and are ubiquitously expressed. Additionally, functional enrichment analysis of those genes in which mutations cause ODs shows that a majority result in premature death or are lethal in the orthologous mouse gene knockout models. To address the limitations of traditional gene-based disease networks, we also construct and analyze OD networks on the basis of shared enriched features (biological processes, cellular components, pathways, phenotypes, and literature citations). Analyzing these functionally-linked OD networks, we identified several additional OD-OD relations that are both phenotypically similar and phenotypically diverse. Surprisingly, we observed that the wiring of the gene-based and other feature-based OD networks are largely different; this suggests that the relationship between ODs cannot be fully captured by the gene-based network alone. PMID:21664998

Pre-persons, commodities or cyborgs: the legal construction and representation of the embryo.

PubMed

Fox, M

2000-01-01

This paper explores how embryos have been represented in law. It argues that two main models have underpinned legal discourse concerning the embryo. One discourse, which has become increasingly prevalent, views embryos as legal subjects or persons. Such representations are facilitated by technological developments such as ultrasound imaging. In addition to influencing Parliamentary debate prior to the passage of the Human Fertilisation and Embryology Act 1990, images of embryos as persons feature prominently in popular culture, including advertising and films, and this discourse came to the fore in the 'orphaned embryo' debate in 1996. The main opposing discourse dismisses embryos as commodifiable objects, which fits with a trend towards legal recognition that reproductive materials such as sperm may be classified as property which may be donated or sold. In the case of cryopreserved embryos these competing perspectives have resulted in litigation over the status of frozen embryos. In this paper I argue that it might be productive to shift the debate from this polarised dispute over whether embryos matter or not, whether they are pre-persons or commodities. Instead, I suggest that we should attempt to locate them in a biotechnological milieu, where cyborg metaphors may be utilised, and questions of how we should treat embryos would be contextualized alongside our response to other cyborgs.

Highly variable penetrance of abnormal phenotypes in embryonic lethal knockout mice

PubMed Central

Wilson, Robert; Geyer, Stefan H.; Reissig, Lukas; Rose, Julia; Szumska, Dorota; Hardman, Emily; Prin, Fabrice; McGuire, Christina; Ramirez-Solis, Ramiro; White, Jacqui; Galli, Antonella; Tudor, Catherine; Tuck, Elizabeth; Mazzeo, Cecilia Icoresi; Smith, James C.; Robertson, Elizabeth; Adams, David J.; Mohun, Timothy; Weninger, Wolfgang J.

2017-01-01

Background: Identifying genes that are essential for mouse embryonic development and survival through term is a powerful and unbiased way to discover possible genetic determinants of human developmental disorders. Characterising the changes in mouse embryos that result from ablation of lethal genes is a necessary first step towards uncovering their role in normal embryonic development and establishing any correlates amongst human congenital abnormalities. Methods: Here we present results gathered to date in the Deciphering the Mechanisms of Developmental Disorders (DMDD) programme, cataloguing the morphological defects identified from comprehensive imaging of 220 homozygous mutant and 114 wild type embryos from 42 lethal and subviable lines, analysed at E14.5. Results: Virtually all mutant embryos show multiple abnormal phenotypes and amongst the 42 lines these affect most organ systems. Within each mutant line, the phenotypes of individual embryos form distinct but overlapping sets. Subcutaneous edema, malformations of the heart or great vessels, abnormalities in forebrain morphology and the musculature of the eyes are all prevalent phenotypes, as is loss or abnormal size of the hypoglossal nerve. Conclusions: Overall, the most striking finding is that no matter how profound the malformation, each phenotype shows highly variable penetrance within a mutant line. These findings have challenging implications for efforts to identify human disease correlates. PMID:27996060

The effect of UV-B radiation on Bufo arenarum embryos survival and superoxide dismutase activity.

PubMed

Herkovits, J; D'Eramo, J L; Fridman, O

2006-03-01

The exposure of Bufo arenarum embryos to 300-310 nm UV-B at a dose of 4,104 Joule/m(2) resulted in 100% lethality within 24 hr while 820 Joule/m(2) was the NOEC value for short-term chronic (10 days) exposure. The dose response curves show that lethal effects are proportional with the dose and achieve its highest value within 48 hr post exposure. The superoxide dismutase (SOD) activity in amphibian embryos for sublethal UV-B exposures was evaluated by means of UV-B treatments with 273 (A), 820(B), 1368(C) and 1915(D) Joule/m(2) at 2 and 5 hours post irradiation. The SOD activity in units/mg protein in A, B, C and D at 2 hr after treatments were 80.72 +/- 14.29, 74.5 +/- 13.19, 39.5 +/- 6.99 and 10.7 +/- 1.89 respectively while for control embryos it was 10.88 +/- 1.31. At 5 hr after treatments the SOD values were similar to those found in control embryos. The results confirm the high susceptibility of amphibian embryos to UV-B and point out that the SOD activity is enhanced by low doses of UV-B irradiation achieving significantly higher values than in control embryos at 2 hr post exposure.

Toxicological aspects of photocatalytic degradation of selected xenobiotics with nano-sized Mn-doped TiO2.

PubMed

Ozmen, Murat; Güngördü, Abbas; Erdemoglu, Sema; Ozmen, Nesrin; Asilturk, Meltem

2015-08-01

The toxic effects of two selected xenobiotics, bisphenol A (BPA) and atrazine (ATZ), were evaluated after photocatalytic degradation using nano-sized, Mn-doped TiO2. Undoped and Mn-doped TiO2 nanoparticles were synthesized. The samples were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), UV-vis-diffuse reflectance spectra (DRS), X-ray fluorescence spectroscopy (XRF), and BET surface area. The photocatalytic efficiency of the undoped and Mn-doped TiO2 was evaluated for BPA and ATZ. The toxicity of the synthesized photocatalysts and photocatalytic by-products of BPA and ATZ was determined using frog embryos and tadpoles, zebrafish embryos, and bioluminescent bacteria. Possible toxic effects were also evaluated using selected enzyme biomarkers. The results showed that Mn-doped TiO2 nanoparticles did not cause significant lethality in Xenopus laevis embryos and tadpoles, but nonfiltered samples caused lethality in zebrafish. Furthermore, Mn-doping of TiO2 increased the photocatalytic degradation capability of nanoparticles, and it successfully degraded BPA and AZT, but degradation of AZT caused an increase of the lethal effects on both tadpoles and fish embryos. Degradation of BPA caused a significant reduction of lethal effects, especially after 2-4h of degradation. However, biochemical assays showed that both Mn-doped TiO2 and the degradation by-products caused a significant change of selected biomarkers on X. laevis tadpoles; thus, the ecological risks of Mn-doped TiO2 should be considered due to nanomaterial applications and for spilled nanoparticles in an aquatic ecosystem. Also, the risk of nanoparticles should be considered using indicator reference biochemical markers to verify the environmental health impacts. Copyright © 2015 Elsevier B.V. All rights reserved.

Bloomsbury report on mouse embryo phenotyping: recommendations from the IMPC workshop on embryonic lethal screening.

PubMed

Adams, David; Baldock, Richard; Bhattacharya, Shoumo; Copp, Andrew J; Dickinson, Mary; Greene, Nicholas D E; Henkelman, Mark; Justice, Monica; Mohun, Timothy; Murray, Stephen A; Pauws, Erwin; Raess, Michael; Rossant, Janet; Weaver, Tom; West, David

2013-05-01

Identifying genes that are important for embryo development is a crucial first step towards understanding their many functions in driving the ordered growth, differentiation and organogenesis of embryos. It can also shed light on the origins of developmental disease and congenital abnormalities. Current international efforts to examine gene function in the mouse provide a unique opportunity to pinpoint genes that are involved in embryogenesis, owing to the emergence of embryonic lethal knockout mutants. Through internationally coordinated efforts, the International Knockout Mouse Consortium (IKMC) has generated a public resource of mouse knockout strains and, in April 2012, the International Mouse Phenotyping Consortium (IMPC), supported by the EU InfraCoMP programme, convened a workshop to discuss developing a phenotyping pipeline for the investigation of embryonic lethal knockout lines. This workshop brought together over 100 scientists, from 13 countries, who are working in the academic and commercial research sectors, including experts and opinion leaders in the fields of embryology, animal imaging, data capture, quality control and annotation, high-throughput mouse production, phenotyping, and reporter gene analysis. This article summarises the outcome of the workshop, including (1) the vital scientific importance of phenotyping embryonic lethal mouse strains for basic and translational research; (2) a common framework to harmonise international efforts within this context; (3) the types of phenotyping that are likely to be most appropriate for systematic use, with a focus on 3D embryo imaging; (4) the importance of centralising data in a standardised form to facilitate data mining; and (5) the development of online tools to allow open access to and dissemination of the phenotyping data.

The Effect of UV-B Radiation on Bufo arenarum Embryos Survival and Superoxide Dismutase Activity

PubMed Central

Herkovits, J.; D’Eramo, J. L.; Fridman, O.

2006-01-01

The exposure of Bufo arenarum embryos to 300–310 nm UV-B at a dose of 4,104 Joule/m2 resulted in 100% lethality within 24 hr while 820 Joule/m2 was the NOEC value for short-term chronic (10 days) exposure. The dose response curves show that lethal effects are proportional with the dose and achieve its highest value within 48 hr post exposure. The superoxide dismutase (SOD) activity in amphibian embryos for sublethal UV-B exposures was evaluated by means of UV-B treatments with 273 (A), 820(B), 1368(C) and 1915(D) Joule/m2 at 2 and 5 hours post irradiation. The SOD activity in units/mg protein in A, B, C and D at 2 hr after treatments were 80.72 ± 14.29, 74.5 ± 13.19, 39.5 ± 6.99 and 10.7 ± 1.89 respectively while for control embryos it was 10.88 ± 1.31. At 5 hr after treatments the SOD values were similar to those found in control embryos. The results confirm the high susceptibility of amphibian embryos to UV-B and point out that the SOD activity is enhanced by low doses of UV-B irradiation achieving significantly higher values than in control embryos at 2 hr post exposure. PMID:16823076

Lethal and sublethal measures of chronic copper toxicity in the eastern narrowmouth toad, Gastrophryne carolinensis.

PubMed

Flynn, R Wesley; Scott, David E; Kuhne, Wendy; Soteropoulos, Diana; Lance, Stacey L

2015-03-01

Many metals are acutely toxic to aquatic organisms at high concentrations and for some metals, such as copper (Cu), even low-level chronic contamination may be cause for conservation concern. Amphibian susceptibility to Cu has been examined in only a few species, and susceptibility is highly variable. The lethal and sublethal effects were examined of chronic aqueous Cu exposure on embryonic and larval eastern narrowmouth toads, Gastrophryne carolinensis. Copper levels as low as 10 μg Cu/L reduced embryonic and larval survival. Embryonic survivorship varied within- and between-source populations, with embryos derived from uncontaminated-wetland parents having greater survival at lower Cu levels than embryos from parents from a metal-contaminated constructed wetland. At 30 μg/L, embryos from the contaminated site had greater survival. Overall survival from oviposition to metamorphosis was 68.9% at 0 μg/L and 5.4% at 10 μg/L. Similarly, embryos exposed to ≥50 μg/L demonstrated developmental delays in transition from embryo to free-swimming larva. These results demonstrate a negative population-specific response to environmentally relevant levels of Cu. © 2014 SETAC.

Predicting adult fish acute lethality with the zebrafish embryo: relevance of test duration, endpoints, compound properties, and exposure concentration analysis.

PubMed

Knöbel, Melanie; Busser, Frans J M; Rico-Rico, Angeles; Kramer, Nynke I; Hermens, Joop L M; Hafner, Christoph; Tanneberger, Katrin; Schirmer, Kristin; Scholz, Stefan

2012-09-04

The zebrafish embryo toxicity test has been proposed as an alternative for the acute fish toxicity test, which is required by various regulations for environmental risk assessment of chemicals. We investigated the reliability of the embryo test by probing organic industrial chemicals with a wide range of physicochemical properties, toxicities, and modes of toxic action. Moreover, the relevance of using measured versus nominal (intended) exposure concentrations, inclusion of sublethal endpoints, and different exposure durations for the comparability with reported fish acute toxicity was explored. Our results confirm a very strong correlation of zebrafish embryo to fish acute toxicity. When toxicity values were calculated based on measured exposure concentrations, the slope of the type II regression line was 1 and nearly passed through the origin (1 to 1 correlation). Measured concentrations also explained several apparent outliers. Neither prolonged exposure (up to 120 h) nor consideration of sublethal effects led to a reduced number of outliers. Yet, two types of compounds were less lethal to embryos than to adult fish: a neurotoxic compound acting via sodium channels (permethrin) and a compound requiring metabolic activation (allyl alcohol).

Genomic structure, promoter identification, and chromosomal mapping of a mouse nuclear orphan receptor expressed in embryos and adult testes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, C.H.; Wei, Li-Na; Copeland, N.G.

We have isolated and characterized overlapping genomic clones containing the complete transcribed region of a newly isolated mouse cDNA encoding an orphan receptor expressed specifically in midgestation embryos and adult testis. This gene spans a distance of more than 50 kb and is organized into 13 exons. The transcription initiation site is located at the 158th nucleotide upstream from the translation initiation codon. All the exon/intron junction sequences follow the GT/AG rule. Based upon Northern blot analysis and the size of the transcribed region of the gene, its transcript was determined to be approximately 2.5 kb. Within approximately 500 hpmore » upstream from the transcription initiation site, several immune response regulatory elements were identified but no TATA box was located. This gene was mapped to the distal region of mouse chromosome 10 and its locus has been designated Tr2-11. Immunohistochemical studies show that the Tr2-11 protein is present mainly in advanced germ cell populations of mature testes and that Tr2-11 gene expression is dramatically decreased in vitamin A-depleted animals. 23 refs., 7 figs.« less

Lethal Dysregulation of Energy Metabolism During Embryonic Vitamin E Deficiency

PubMed Central

McDougall, Melissa; Choi, Jaewoo; Kim, Hye-Kyeong; Bobe, Gerd; Stevens, J. Frederik; Cadenas, Enrique; Tanguay, Robert; Traber, Maret G.

2017-01-01

Vitamin E (α-tocopherol, VitE) was discovered in 1922 for its role in preventing embryonic mortality. We investigated the underlying mechanisms causing lethality using targeted metabolomics analyses of zebrafish VitE-deficient embryos over five days of development, which coincided with their increased morbidity and mortality. VitE deficiency resulted in peroxidation of docosahexaenoic acid (DHA), depleting DHA-containing phospholipids, especially phosphatidylcholine, which also caused choline depletion. This increased lipid peroxidation also increased NADPH oxidation, which depleted glucose by shunting it to the pentose phosphate pathway. VitE deficiency was associated with mitochondrial dysfunction with concomitant impairment of energy homeostasis. The observed morbidity and mortality outcomes could be attenuated, but not fully reversed, by glucose injection into VitE-deficient embryos at developmental day one. Thus, embryonic VitE deficiency in vertebrates leads to a metabolic reprogramming that adversely affects methyl donor status and cellular energy homeostasis with lethal outcomes. PMID:28095320

Production of maternal-zygotic mutant zebrafish by germ-line replacement.

PubMed

Ciruna, Brian; Weidinger, Gilbert; Knaut, Holger; Thisse, Bernard; Thisse, Christine; Raz, Erez; Schier, Alexander F

2002-11-12

We report a generally applicable strategy for transferring zygotic lethal mutations through the zebrafish germ line. By using a morpholino oligonucleotide that blocks primordial germ cell (PGC) development, we generate embryos devoid of endogenous PGCs to serve as hosts for the transplantation of germ cells derived from homozygous mutant donors. Successful transfers are identified by the localization of specifically labeled donor PGCs to the region of the developing gonad in chimeric embryos. This strategy, which results in the complete replacement of the host germ line with donor PGCs, was validated by the generation of maternal and maternal-zygotic mutants for the miles apart locus. This germ-line replacement technique provides a powerful tool for studying the maternal effects of zygotic lethal mutations. Furthermore, the ability to generate large clutches of purely mutant embryos will greatly facilitate embryological, genetic, genomic, and biochemical studies.

Production of maternal-zygotic mutant zebrafish by germ-line replacement

PubMed Central

Ciruna, Brian; Weidinger, Gilbert; Knaut, Holger; Thisse, Bernard; Thisse, Christine; Raz, Erez; Schier, Alexander F.

2002-01-01

We report a generally applicable strategy for transferring zygotic lethal mutations through the zebrafish germ line. By using a morpholino oligonucleotide that blocks primordial germ cell (PGC) development, we generate embryos devoid of endogenous PGCs to serve as hosts for the transplantation of germ cells derived from homozygous mutant donors. Successful transfers are identified by the localization of specifically labeled donor PGCs to the region of the developing gonad in chimeric embryos. This strategy, which results in the complete replacement of the host germ line with donor PGCs, was validated by the generation of maternal and maternal-zygotic mutants for the miles apart locus. This germ-line replacement technique provides a powerful tool for studying the maternal effects of zygotic lethal mutations. Furthermore, the ability to generate large clutches of purely mutant embryos will greatly facilitate embryological, genetic, genomic, and biochemical studies. PMID:12397179

Nanotoxicological and teratogenic effects: A linkage between dendrimer surface charge and zebrafish developmental stages.

PubMed

Calienni, Maria Natalia; Feas, Daniela Agustina; Igartúa, Daniela Edith; Chiaramoni, Nadia Silvia; Alonso, Silvia Del Valle; Prieto, Maria Jimena

2017-12-15

This article reports novel results about nanotoxicological and teratogenic effects of the PAMAM dendrimers DG4 and DG4.5 in zebrafish (Danio rerio). Zebrafish embryos and larvae were used as a rapid, high-throughput, cost-effective whole-animal model. The objective was to provide a more comprehensive and predictive developmental toxicity screening of DG4 and DG4.5 and test the influence of their surface charge. Nanotoxicological and teratogenic effects were assessed at developmental, morphological, cardiac, neurological and hepatic level. The effect of surface charge was determined in both larvae and embryos. DG4 with positive surface charge was more toxic than DG4.5 with negative surface charge. DG4 and DG4.5 induced teratogenic effects in larvae, whereas DG4 also induced lethal effects in both zebrafish embryos and larvae. However, larvae were less sensitive than embryos to the lethal effects of DG4. The platform of assays proposed and data obtained may contribute to the characterization of hazards and differential effects of these nanoparticles. Copyright © 2017 Elsevier Inc. All rights reserved.

Independent degeneration of W and Y sex chromosomes in frog Rana rugosa.

PubMed

Miura, Ikuo; Ohtani, Hiromi; Ogata, Mitsuaki

2012-01-01

The frog Rana rugosa uniquely possesses two different sex-determining systems of XX/XY and ZZ/ZW, separately in the geographic populations. The sex chromosomes of both types share the same origin at chromosome 7, and the structural differences between X and Y or Z and W were evolved through two inversions. In order to ascertain the mechanisms of degeneration of W and Y chromosomes, we gynogenetically produced homozygous diploids WW and YY and examined their viability. Tadpoles from geographic group N (W(N)W(N)) containing three populations died of edema at an early developmental stage within 10 days after hatching, while tadpoles from the geographic group K (W(K)W(K)) that contained two populations died of underdeveloped growth at a much later stage, 40-50 days after fertilization. On the contrary, W(N)W(K) and W(K)W(N) hybrid embryos were viable, successfully passed the two lethal stages, and survived till the attainment of adulthood. The observed survival implies that the lethal genes of the W chromosomes are not shared by the two groups and thus demonstrates their independent degeneration histories between the local groups. In sharp contrast, a sex-linked gene of androgen receptor gene (AR) from the W chromosome was down-regulated in expression in both the groups, suggesting that inactivation of the W-AR allele preceded divergence of the two groups and appearance of the lethal genes. Besides, the YY embryos died of cardiac edema immediately after hatching. The symptom of lethality and the stage of developmental arrest differed from those for either of WW lethal embryos. We therefore conclude that the W and Y chromosomes involve no evolutionary common scenario for degeneration.

Altered trophoblast proliferation is insufficient to account for placental dysfunction in Egfr null embryos

PubMed Central

Dackor, J.; Strunk, K. E.; Wehmeyer, M. M.; Threadgill, D. W.

2007-01-01

Homozygosity for the Egfrtm1Mag null allele in mice leads to genetic background dependent placental abnormalities and embryonic lethality. Molecular mechanisms or genetic modifiers that differentiate strains with surviving versus non-surviving Egfr nullizygous embryos have yet to be identified. Egfr transcripts in wildtype placenta was quantified by ribonuclease protection assay (RPA) and the lowest level of Egfr mRNA expression was found to coincide with Egfrtm1Mag homozygous lethality. Immunohistochemical analysis of ERBB family receptors, ERBB2, ERBB3, and ERBB4, showed similar expression between Egfr wildtype and null placentas indicating that Egfr null trophoblast do not up-regulate these receptors to compensate for EGFR deficiency. Significantly fewer numbers of bromodeoxyuridine (BrdU) positive trophoblast were observed in Egfr nullizygous placentas and Cdc25a and Myc, genes associated with proliferation, were significantly down-regulated in null placentas. However, strains with both mild and severe placental phenotypes exhibit reduced proliferation suggesting that this defect alone does not account for strain-specific embryonic lethality. Consistent with this hypothesis, intercrosses generating mice null for cell cycle checkpoint genes (Trp53, Rb1, Cdkn1a, Cdkn1b or Cdkn2c) in combination with Egfr deficiency did not increase survival of Egfr nullizygous embryos. Since complete development of the spongiotrophoblast compartment is not required for survival of Egfr nullizygous embryos, reduction of this layer that is commonly observed in Egfr nullizygous placentas likely accounts for the decrease in proliferation. PMID:17822758

Developmental Effects and Estrogenicity of Bisphenol A Alternatives in a Zebrafish Embryo Model.

PubMed

Mu, Xiyan; Huang, Ying; Li, Xuxing; Lei, Yunlei; Teng, Miaomiao; Li, Xuefeng; Wang, Chengju; Li, Yingren

2018-03-06

In order to understand the negative effects of bisphenol A (BPA) alternatives comprehensively, zebrafish embryos were used to assess the lethality, developmental effects, and estrogenic activity of bisphenol analogues. The in silico estrogenic activities of bisphenol analogues were assayed by binding simulation. According to our results, the lethality of bisphenol analogues decreased in order of bisphenol AF (BPAF) > BPA > bisphenol F (BPF) > bisphenol S (BPS). BPAF and BPF induced significant effects on zebrafish embryos, including decreased heart rate, hatching inhibition, and teratogenic effects. The binding potentials of bisphenol analogues toward zebrafish ERs (zfERS) decreased in the following order: BPAF > BPA > BPF > BPS. Among the three subtypes of zfERs, zfERβ2 showed the highest binding activity toward the bisphenols, followed by zfERα and zfERβ1. In vivo estrogenic activity tests showed that BPAF, BPA, and BPF significantly enhanced the protein levels of ERα along with the mRNA levels of esr1, esr2a, esr2b, and vtg1 in zebrafish embryos. Esr2b showed the strongest response to BPAF and BPA exposure among the three esrs. In contrast, BPS did not significantly regulate ER protein level or ER transcription. In conclusion, BPAF showed the highest lethality, developmental effects, and estrogenic activity (both in silico and in vivo) followed by BPA and BPF. BPS showed the weakest toxicity and estrogenic activity. zfERβ2 might act as the main target among the three ER subtypes of zebrafish after exposure to BPAF and BPA.

Effects of cyanobacterial biomass and purified microcystins on malformations in Xenopus laevis: teratogenesis assay (FETAX).

PubMed

Dvoráková, Dagmar; Dvoráková, Katerina; Bláha, Ludek; Marsálek, Blahoslav; Knotková, Zora

2002-12-01

Xenopus laevis (African clawed frog) embryos in a 96-h teratogenesis assay (FETAX) were exposed to 0-250 microg/L and 500 microg/L of purified microcystin-LR (MCYST-LR) for the estimation of lethality, as well as to equivalent concentrations of biomass containing MCYST-LR (natural water bloom dominated by Microcystis aeruginosa) and biomass without MCYST-LR (bloom dominated by Microcystis wesenbergii). The highest tested concentrations of purified MCYST-LR caused up to 30% lethality after a 96-h exposure, corresponding to a LC(25) of 380 microg/L. Cyanobacterial biomass containing MCYST-LR caused significant lethality up to 50% at the highest tested concentrations (300 mg/L, i.e., 250 microg/L of MCYST-LR). The estimated 96-h LC(25) values varied from 125 mg/L (biomass containing MCYST-LR) up to 232 mg/L (biomass without MCYST-LR). A statistically significant increase in the number of malformed embryos was observed after exposure to cyanobacterial samples. Purified MCYST-LR at and above 25 microg/L significantly increased the number of malformations, with 53% of surviving embryos malformed in the highest tested concentration, 250 microg/L (EC(25) = 27 microg/L). Exposure to the highest concentration of MCYST-LR containing biomass resulted in more than 60% of the embryos being malformed and an EC(25) of 52 mg/L (i.e., 43 microg of MCYST-LR/L). Cyanobacterial biomass with no natural microcystin also induced substantial malformations-about 50% aberrant embryos at the highest concentration, 300 mg/L (EC(25) = 75 mg/L). External additions of purified MCYST-LR to the biomass that was originally without microcystins resulted in a slight additional increase in the rate of malformations (80% at the highest concentration, 300 mg of biomass plus 250 microg of MCYST-LR per liter). A comparison of lethality and effects on malformations (teratogenic index, TI = LC(25)/EC(25)) showed that all samples had significant teratogenic potential in the FETAX assay (TI(MCYST-LR) = 14; TI for biomass with and without microcystin ranged between 2.4 and 3.1, respectively). We conclude that cyanobacterial water blooms can significantly alter the normal development of amphibian embryos. Copyright 2002 Wiley Periodicals, Inc.

Toxicity testing of leachate from waste landfills using medaka (Oryzias latipes) for monitoring environmental safety.

PubMed

Osaki, Kae; Kashiwada, Shosaku; Tatarazako, Norihisa; Ono, Yoshiro

2006-06-01

To investigate the environmental safety of waste disposal landfill sites and of land reclaimed from such sites, we evaluated the toxicity of leachate from these sites by a combination of bioassays in the Japanese killifish medaka Oryzias latipes. We tested for lethal toxicity in adult and larval medaka and for hatching inhibition of embryos from eggs. As biochemical evidence of the effects of leachate exposure, CYP1A (EROD activity) and vitellogenin (Vtg) were induced. We also bioassayed water-treated leachate and downstream river water. Leachate solution was lethal to larval and adult medaka. Embryo hatchability was inhibited, and abnormal hatching, spinal deformity and anisophthalmia occurred in embryos exposed to leachate solution. CYP1A was induced by exposure to leachate solution diluted to 1.0%, and EROD activity was significantly higher than in control. Vtg and unknown proteins were induced in the sera of male medaka exposed to the diluted leachate solution. Conventional water treatments worked effectively to remove toxic compounds but did not work well to remove element ions, including heavy metals. Treated leachate produced neither lethal toxicity nor hatching abnormalities during the exposure period. Fish toxicity tests for leachate would be useful for monitoring the environmental safety of landfill sites.

Unexpectedly high mortality in Pacific herring embryos exposed to the 2007 Cosco Busan oil spill in San Francisco Bay.

PubMed

Incardona, John P; Vines, Carol A; Anulacion, Bernadita F; Baldwin, David H; Day, Heather L; French, Barbara L; Labenia, Jana S; Linbo, Tiffany L; Myers, Mark S; Olson, O Paul; Sloan, Catherine A; Sol, Sean; Griffin, Frederick J; Menard, Karl; Morgan, Steven G; West, James E; Collier, Tracy K; Ylitalo, Gina M; Cherr, Gary N; Scholz, Nathaniel L

2012-01-10

In November 2007, the container ship Cosco Busan released 54,000 gallons of bunker fuel oil into San Francisco Bay. The accident oiled shoreline near spawning habitats for the largest population of Pacific herring on the west coast of the continental United States. We assessed the health and viability of herring embryos from oiled and unoiled locations that were either deposited by natural spawning or incubated in subtidal cages. Three months after the spill, caged embryos at oiled sites showed sublethal cardiac toxicity, as expected from exposure to oil-derived polycyclic aromatic compounds (PACs). By contrast, embryos from the adjacent and shallower intertidal zone showed unexpectedly high rates of tissue necrosis and lethality unrelated to cardiotoxicity. No toxicity was observed in embryos from unoiled sites. Patterns of PACs at oiled sites were consistent with oil exposure against a background of urban sources, although tissue concentrations were lower than expected to cause lethality. Embryos sampled 2 y later from oiled sites showed modest sublethal cardiotoxicity but no elevated necrosis or mortality. Bunker oil contains the chemically uncharacterized remains of crude oil refinement, and one or more of these unidentified chemicals likely interacted with natural sunlight in the intertidal zone to kill herring embryos. This reveals an important discrepancy between the resolving power of current forensic analytical chemistry and biological responses of keystone ecological species in oiled habitats. Nevertheless, we successfully delineated the biological impacts of an oil spill in an urbanized coastal estuary with an overlapping backdrop of atmospheric, vessel, and land-based sources of PAC pollution.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herkovits, J.; Herkovits, F.D.; Perez-Coll

As a result of their aquatic embryonic and larval development, many species of amphibians are potentially affected by adverse environmental conditions. In this study the possibility of reducing the lethal effect of aluminum (ALC13, Mallinckrodt) in Bufo arenarum embryos by means of simultaneous zinc (ZnSO4) treatment is reported. The aluminum hazard was evaluated in a 7 day renewal toxicity testing study conducted with batches of 10 individuals (by quadruplicate) in six concentrations of aluminum plus the control at 20 C. The pH of the experimental solutions were measured. The LC100 expressed as Al(3 +) mg/L at 24 and up tillmore » 168 hours of treatment were 0.9 (the pH of the solution was 6.2 while in control Holtfreter solution the pH was 6.8). Therefore, aluminum exert a lethal effect on amphibian embryos in concentrations which reduce only slightly the pH of the maintaining solution. The lethal effect of aluminum could be reduced 100% by means of simultaneous treatment with 2 mg Zn(2 +)/L. The results point out the high sensibility of the amphibian embryos to aluminum (LC100/24hs:0.9mg Al(3 +)/L) and therefore, episodic increases in dissolved aluminum, usually concomitant with surface water pH decreases, could produce very harmful effects during embryonic stages of amphibians. The noteworthy beneficial effect of zinc against the lethal effect of aluminum could be of practical value in reducing the harmful effects exerted by aluminum. The conspicuous Al-Zn antagonism points out the need of biological test systems for recording the integrated effects of substances released to the environment.« less

Biological damage induced by ionizing cosmic rays in dry Arabidopsis seeds.

PubMed

Kranz, A R; Bork, U; Bucker, H; Reitz, G

1990-01-01

In September 1987 dry seeds containing embryos of the crucifer plant Arabidopsis thaliana (L.) Heynh, were flown in orbit for 13 days on the Kosmos 1887 satellite. The seeds were fixed on CNd detectors and stored in units of Biorack type I/O. One unit was exposed inside, another one outside the satellite. The temperature profile of the flown seeds inside the satellite was simulated on earth in an identical backup control sample (BC). An additional control (SC) was studied with the original seeds sample. By use of the CNd-detector, HZE-tracks were measured with a PC-assisted microscope. The biological damages were investigated by growing the seeds under controlled climatic conditions. The following biological endpoints of the cosmic radiation damage were studied: germination, radicle length, sublethality, morphological aberrations, flower development, tumorization, embryo lethality inside the siliques. The summarized damage (D) and the mutation frequencies of embyronic lethal genes were calculated. The following results were obtained: the damages increase significantly in orbit at all biological endpoints; germination and fiowerings especially, as well as embryo lethality of fruits and lethal mutation frequency, were maximum mostly for HZE-hit seeds. Additionally, an increase of damage was observed for the seeds of the outside-exposed Biorack in comparison to the inside ones, which was probably caused by less radiation shielding and free space vacuum. The significance of the results obtained is discussed with respect to stress and risk and, thus, the quality of the RBE-factors and heavy ionizing radiation all needed for the very definition of radiation protection standards in space.

Acute toxicity of polybrominated diphenyl ethers (PBDEs) for turbot (Psetta maxima) early life stages (ELS).

PubMed

Mhadhbi, Lazhar; Fumega, José; Boumaiza, Moncef; Beiras, Ricardo

2012-03-01

The environmental presence of polybrominated diphenyl ethers (PBDEs), among which BDE-47 and BDE-99 are particularly abundant, makes toxicity data necessary to assess the hazard risk posed by PBDE to aquatic organisms. This study examines the effects of BDE-47 and BDE-99 on embryo-larval stages of the marine flatfish turbot. The turbot embryos were exposed at nominal concentrations of BDE-47 and BDE-99 for 6 days. Selected dose levels were relevant for investigating sublethal and lethal effects. Both tested compounds caused lethal toxicity as well as non-lethal malformations during embryo development. We found a high toxic potency of BDE-47 compared to BDE-99 (LC₅₀ values for embryos and larvae, respectively, BDE-47: 27.35 and 14.13 μg L⁻¹; BDE-99: 38.28 and 29.64 μg L⁻¹). The present study shows high sensitivity of fish early life stages (ELS) to PBDE compounds. Based on environmental concentrations of dissolved PBDEs from various aquatic ecosystems, waterborne BDE-47 and BDE-99 pose little risk of acute toxicity to marine fish at relevant environmental concentrations. Turbot fish ELS proved to be an excellent model for the study of ecotoxicity of contaminants in seawater. The results demonstrate harmful effects of PBDE on turbot ELS at concentrations in the range of parts per billion units. In the perspective of risk assessment, ELS endpoints provide rapid, cost-effective and ecologically relevant information, and links should be sought between these short-term tests and effects of long-term exposures in more realistic scenarios.

Plastidial NAD-Dependent Malate Dehydrogenase: A Moonlighting Protein Involved in Early Chloroplast Development Through its Interaction with an FtsH12-FtsHi Protease Complex.

PubMed

Schreier, Tina B; Antoine, Cléry; Schläfli, Michael; Galbier, Florian; Stadler, Martha; Demarsy, Emilie; Albertini, Daniele; Maier, Benjamin A; Kessler, Felix; Hörtensteiner, Stefan; Zeeman, Samuel C; Kötting, Oliver

2018-06-22

Malate dehydrogenases (MDH) convert malate to oxaloacetate using NAD(H) or NADP(H) as a cofactor. Arabidopsis thaliana mutants lacking plastidial NAD-dependent MDH (pdnad-mdh) are embryo-lethal, and constitutive silencing (miR-mdh-1) causes a pale, dwarfed phenotype. The reason for these severe phenotypes is unknown. Here, we rescued the embryo lethality of pdnad-mdh via embryo-specific expression of pdNAD-MDH. Rescued seedlings developed white leaves with aberrant chloroplasts and failed to reproduce. Inducible silencing of pdNAD-MDH at the rosette stage also resulted in white newly emerging leaves. These data suggest that pdNAD-MDH is important for early plastid development, which is consistent with the reductions in major plastidial galactolipid, carotenoid and protochlorophyllide levels in miR-mdh-1 seedlings. Surprisingly, the targeting of other NAD-dependent MDH isoforms to the plastid did not complement the embryo lethality of pdnad-mdh, while expression of enzymatically inactive pdNAD-MDH did. These complemented plants grew indistinguishably from the wild type. Both active and inactive forms of pdNAD-MDH interact with a heteromeric AAA-ATPase complex at the inner membrane of the chloroplast envelope. Silencing the expression of FtsH12, a key member of this complex, resulted in a phenotype that strongly resembles miR-mdh-1. We propose that pdNAD-MDH is essential for chloroplast development due to its moonlighting role in stabilizing FtsH12, distinct from its enzymatic function. © 2018 American Society of Plant Biologists. All rights reserved.

Toxicogenomic assessment of 6-OH-BDE47 induced ...

EPA Pesticide Factsheets

Hydroxylated and methoxylated polybrominated diphenyl ethers (OH-/MeO-PBDEs) are analogs of PBDEs with hundreds of possible structures and many of them can activate aryl hydrocarbon receptor (AhR), however, the in vivo evidence on the toxicity of OH-/MeO-PBDEs are still very limited. 6-OH-BDE47 is a relatively potent AhR activator and a predominant congener of OH-PBDEs detected in the environment. Here the developmental toxicity of 6-OH-BDE47 in chicken embryos was assessed using a toxicogenomic approach. Fertilized chicken eggs were dosed via in ovo administration of 0.006 to 0.474 nmol 6-OH-BDE47/g egg followed by 18-days incubation. Significant embryo mortality (LD50=0.294 pmol/g egg) and increased hepatic somatic index (HSI) were caused by 6-OH-BDE47 exposure. The functional enrichment of differentially expressed genes (DEGs) associated with oxidative phosphorylation, generation of precursor metabolites and energy, and electron transport chain suggest that 6-OH-BDE47 exposure may disrupt the embryo development by altering the function of energy production in mitochondrion. Moreover, AhR mediated responses including up-regulation of CYP1A4 was observed in the livers of embryos exposed to 6-OH-BDE47. Overall, this study confirmed the prediction of embryo lethality by 6-OH-BDE47 consistent with an adverse outcome pathway (AOP) linking AhR activation to embryo lethality. The results provide an example of application of AOP in the hazard and ecological risk asse

RELATIVE EFFECTIVENESS OF 14 Mev NEUTRONS AND 200 KVP X-RAYS FOR PRODUCTION OF LETHALITY IN GRASSHOPPER EMBRYOS. A PRELIMINARY STUDY (thesis)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bicker, A.E.

1962-05-01

A test system using the grasshopper embryo with hatching as the criterion for the end-point was proposed to determine the relative effectiveness of 14 Mev neutrons and 200 kvp x rays. Eggs of Chortophaga (14 day) and Encoptolophus (14 day and terminal) were subjected to various doses of both radiations. Values for the medial lethal doses from the data obtained were 650 rads for Chortophaga, 760 rads for Encoptolophus (14 day), and 1800 rads for Encoptolophus (terminal). The shape of the dose-effect curve relative to x- irradiation survival was assumed to be unchanged so that an estimate of the LD/more » sub 50/ could be made. The value obtained was 370 rads. The RBE of 14 Mev neutrons and 200 kvp x rays on Chortophaga (14 day) embryos was 1.76. It was concluded that Chortophaga and Encoptolophus embryos irradiated in the 14 day development stage with hatching as an end-point constitute valid systems for the measurement of the relative effectiveness of the 14 Mev neutrons and 200 kvp x rays. (P.C.H.)« less

Targeted Disruption of Mouse Yin Yang 1 Transcription Factor Results in Peri-Implantation Lethality

PubMed Central

Donohoe, Mary E.; Zhang, Xiaolin; McGinnis, Lynda; Biggers, John; Li, En; Shi, Yang

1999-01-01

Yin Yang 1 (YY1) is a zinc finger-containing transcription factor and a target of viral oncoproteins. To determine the biological role of YY1 in mammalian development, we generated mice deficient for YY1 by gene targeting. Homozygosity for the mutated YY1 allele results in embryonic lethality in the mouse. YY1 mutants undergo implantation and induce uterine decidualization but rapidly degenerate around the time of implantation. A subset of YY1 heterozygote embryos are developmentally retarded and exhibit neurulation defects, suggesting that YY1 may have additional roles during later stages of mouse embryogenesis. Our studies demonstrate an essential function for YY1 in the development of the mouse embryo. PMID:10490658

FIRST RESULTS ON X-RAY-INDUCED GENETIC DAMAGE IN ARTEMIA SALINA LEACH

DOE Office of Scientific and Technical Information (OSTI.GOV)

Metalli, P.; Ballardin, E.

1962-01-01

Prophase oocytes of diploid and tetraploid pantenogenetic Antemia salina were x irradiated with 1000 r and damage was scored as oocyte or embryo lethal mutations at the first (X/sub 1/) and at the second (X/sub 2/) generations after irradiation. Dominant lethality shown at X/sub 1/ was much greater for the diploid strain than for the tetraploid; lethality observed at X/sub 2/ was increased with respect to X/sub 1/ in the diploid strain, while in the tetraploid it remained unmodified. (auth)

Failure of vincristine induce twinning

NASA Technical Reports Server (NTRS)

Binder, M.

1984-01-01

Mammalian ova do not contain axes of symmetry from which are derived embryonic axes of symmetry. Mammalian axis determination is an early embryologic event occurring at about the time that monozygous twinning in mice. (Kaufma MH & O'Shea KS, 1978, Nature 276:707) and an attempt was made to reproduce their work in several strains of mice. Over 3200 embryos were examined without any twins being found. To rule out the possibility that vincristine caused twinning plus some lethal malformation (with subsequent resorption of the embryo) the embryos were examined 36-60 hours after vincristine treatment.

Potential protective effect of L-cysteine against the toxicity of acrylamide and furan in exposed Xenopus laevis embryos: an interaction study.

PubMed

Williams, John Russell; Rayburn, James R; Cline, George R; Sauterer, Roger; Friedman, Mendel

2014-08-06

The embryo toxicities of two food-processing-induced toxic compounds, acrylamide and furan, with and without added L-cysteine were examined individually and in mixtures using the frog embryo teratogenesis assay-Xenopus (FETAX). The following measures of developmental toxicity were used: (a) 96 h LC50, the median concentration causing 50% embryo lethality; (b) 96 h EC50, the median concentration causing 50% malformations of the surviving embryos; and (c) teratogenic index (96 h LC50/96 h EC50), an estimate of teratogenic risk. Calculations of toxic units (TU) were used to assess possible antagonism, synergism, or response addition of several mixtures. The evaluated compounds demonstrated counterintuitive effects. Furan had lower than expected toxicity in Xenopus embryos and, unlike acrylamide, does not seem to be teratogenic. However, the short duration of the tests may not show the full effects of furan if it is truly primarily genotoxic and carcinogenic. L-Cysteine showed unexpected properties in the delay of hatching of the embryos. The results from the interaction studies between combination of two or three components (acrylamide plus L-cysteine; furan plus L-cysteine; acrylamide plus furan; acrylamide plus furan and L-cysteine) show that furan and acrylamide seem to have less than response addition at 1:1 toxic unit ratio in lethality. Acrylamide and L-cysteine show severe antagonism even at low 19 acrylamide/1 L-cysteine TU ratios. Data from the mixture of acrylamide, furan, and L-cysteine show a slight antagonism, less than would have been expected from binary mixture exposures. Bioalkylation mechanisms and their prevention are discussed. There is a need to study the toxicological properties of mixtures of acrylamide and furan concurrently formed in heat-processed food.

The Roles of Glutathione Peroxidases during Embryo Development

PubMed Central

Ufer, Christoph; Wang, Chi Chiu

2011-01-01

Embryo development relies on the complex interplay of the basic cellular processes including proliferation, differentiation, and apoptotic cell death. Precise regulation of these events is the basis for the establishment of embryonic structures and the organ development. Beginning with fertilization of the oocyte until delivery the developing embryo encounters changing environmental conditions such as varying levels of oxygen, which can give rise to reactive oxygen species (ROS). These challenges are met by the embryo with metabolic adaptations and by an array of anti-oxidative mechanisms. ROS can be deleterious by modifying biological molecules including lipids, proteins, and nucleic acids and may induce abnormal development or even embryonic lethality. On the other hand ROS are vital players of various signaling cascades that affect the balance between cell growth, differentiation, and death. An imbalance or dysregulation of these biological processes may generate cells with abnormal growth and is therefore potentially teratogenic and tumorigenic. Thus, a precise balance between processes generating ROS and those decomposing ROS is critical for normal embryo development. One tier of the cellular protective system against ROS constitutes the family of selenium-dependent glutathione peroxidases (GPx). These enzymes reduce hydroperoxides to the corresponding alcohols at the expense of reduced glutathione. Of special interest within this protein family is the moonlighting enzyme glutathione peroxidase 4 (Gpx4). This enzyme is a scavenger of lipophilic hydroperoxides on one hand, but on the other hand can be transformed into an enzymatically inactive cellular structural component. GPx4 deficiency – in contrast to all other GPx family members – leads to abnormal embryo development and finally produces a lethal phenotype in mice. This review is aimed at summarizing the current knowledge on GPx isoforms during embryo development and tumor development with an emphasis on GPx4. PMID:21847368

The Roles of Glutathione Peroxidases during Embryo Development.

PubMed

Ufer, Christoph; Wang, Chi Chiu

2011-01-01

Embryo development relies on the complex interplay of the basic cellular processes including proliferation, differentiation, and apoptotic cell death. Precise regulation of these events is the basis for the establishment of embryonic structures and the organ development. Beginning with fertilization of the oocyte until delivery the developing embryo encounters changing environmental conditions such as varying levels of oxygen, which can give rise to reactive oxygen species (ROS). These challenges are met by the embryo with metabolic adaptations and by an array of anti-oxidative mechanisms. ROS can be deleterious by modifying biological molecules including lipids, proteins, and nucleic acids and may induce abnormal development or even embryonic lethality. On the other hand ROS are vital players of various signaling cascades that affect the balance between cell growth, differentiation, and death. An imbalance or dysregulation of these biological processes may generate cells with abnormal growth and is therefore potentially teratogenic and tumorigenic. Thus, a precise balance between processes generating ROS and those decomposing ROS is critical for normal embryo development. One tier of the cellular protective system against ROS constitutes the family of selenium-dependent glutathione peroxidases (GPx). These enzymes reduce hydroperoxides to the corresponding alcohols at the expense of reduced glutathione. Of special interest within this protein family is the moonlighting enzyme glutathione peroxidase 4 (Gpx4). This enzyme is a scavenger of lipophilic hydroperoxides on one hand, but on the other hand can be transformed into an enzymatically inactive cellular structural component. GPx4 deficiency - in contrast to all other GPx family members - leads to abnormal embryo development and finally produces a lethal phenotype in mice. This review is aimed at summarizing the current knowledge on GPx isoforms during embryo development and tumor development with an emphasis on GPx4.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herkovits, J.; Herkovits, F.D.; Fernandez, A.

The identification of mercurium hazard for Cnesterodon decemmaculatus and Bufo arenarum (embryos) was evaluated in a renewal toxicity test system at 20 C and informed as LC100, LC50 and NOEC for 24 and up till 96 hours of exposure (acute Toxicity Profile -- TPa -- for mercurium). On addition the beneficial effect of zinc against the lethal effect of mercurium is reported. The test with fish were conducted maintaining 10 individuals in 1 L of EPA water (by quadruplicate) in six concentrations of Hg plus controls, while for amphibian, batches of 10 Bufo arenarum embryos at stage 25 (by quadruplicate)more » were maintained in 40 ml of Holtfreter`s solution in six concentration of Hg + (HgCl) plus controls. The LC100, LC50 and NOEC for fishes expressed in Hg (+) mg/L were: 0.60, 0.25 and 0.10 for 24 hours of exposure. These values increased very slightly at least up till 96 hours of exposure. Therefore, Bufo arenarum seems to be about three times more sensitive than Cnesterodon decemmaculatus to mercurium. By means of simultaneous mercurium-zinc treatment (ZnSO4) the lethal effect of mercurium could be reduced in amphibians up till 100% with 18 mg Zn2+/L, while for the fish the best result obtained was a reduction of about 50% of lethality within the first 96 hours of treatment with 20 mg Zn2+/L. As a whole the results point out the high susceptibility of amphibian embryos to xenobiotics, the beneficial effect of zinc against embryos to xenobiotics, the beneficial effect of zinc against toxicity exerted by Hg and the need of biological test systems for recording the combined effects of substances released to the environment.« less

Primary Sex Determination in Drosophila melanogaster Does Not Rely on the Male-Specific Lethal Complex.

PubMed

Erickson, James W

2016-02-01

It has been proposed that the Male Specific Lethal (MSL) complex is active in Drosophila melanogaster embryos of both sexes prior to the maternal-to-zygotic transition. Elevated gene expression from the two X chromosomes of female embryos is proposed to facilitate the stable establishment of Sex-lethal (Sxl) expression, which determines sex and represses further activity of the MSL complex, leaving it active only in males. Important supporting data included female-lethal genetic interactions between the seven msl genes and either Sxl or scute and sisterlessA, two of the X-signal elements (XSE) that regulate early Sxl expression. Here I report contrary findings that there are no female-lethal genetic interactions between the msl genes and Sxl or its XSE regulators. Fly stocks containing the msl3(1) allele were found to exhibit a maternal-effect interaction with Sxl, scute, and sisterlessA mutations, but genetic complementation experiments showed that msl3 is neither necessary nor sufficient for the female-lethal interactions, which appear to be due to an unidentified maternal regulator of Sxl. Published data cited as evidence for an early function of the MSL complex in females, including a maternal effect of msl2, have been reevaluated and found not to support a maternal, or other effect, of the MSL complex in sex determination. These findings suggest that the MSL complex is not involved in primary sex determination or in X chromosome dosage compensation prior to the maternal-to-zygotic transition. Copyright © 2016 by the Genetics Society of America.

Incorporation of Tritium-labelled Thymidine in Bufo $female$ × Rana temporaria $male$ Hybrid Embryos

DOE Office of Scientific and Technical Information (OSTI.GOV)

TENCER, B.

1961-04-01

Two-cell stages of hybrid embryos resulting from the cross-fertilization of Bufo and Rana temporaria were incubated for 17 hrs in a medium containing tritium-labeled thymidine. The embryos were fixed by freeze-substitution and the incorporation of tritium studied by the radioautographic technique. The embryos stopped development at the late blastula stage. Labeling of desoxyribonucleic acid was demonstrated in morula as well as in blastula cells of the lethal hybrids. Tritium-labeled thymidine was shown to be incorporated into desoxyribonucleic acid 24 hr after development stopped, which suggests that the block in development was not due to the arrest of desoxyribonucleic acid synthesis.more » (C.H.)« less

Embryo toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin to the wood duck (Aix sponsa)

USGS Publications Warehouse

Augspurger, T.P.; Tillitt, D.E.; Bursian, S.J.; Fitzgerald, S.D.; Hinton, D.E.; Di Giulio, R.T.

2008-01-01

We examined the sensitivity of the wood duck (Aix sponsa) embryo to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) by injecting the toxicant into their eggs. Six groups of wood duck eggs (n = 35 to 211 per trial) were injected with 0 to 4600 pg TCDD/g egg between 2003 and 2005. Injections were made into yolk prior to incubation, and eggs were subsequently incubated and assessed weekly for mortality. Significant TCDD-induced mortality was not observed through day 25 (90% of incubation). Liver, heart, eye, and brain histology were generally unremarkable. Hepatic ethoxyresorufin-O-deethylase activity, a biomarker of dioxin-like compound exposure, was induced by 12-fold in the 4600 pg/g treatment relative to controls. The median lethal dose for chicken (Gallus domesticus) eggs we dosed identically to wood duck eggs was about 100 pg/g, similar to other assessments of chickens. Among dioxin-like compound embryo lethality data for 15 avian genera, the wood duck 4600 pg/g no-observed-effect level ranks near the middle. Because no higher doses were tested, wood ducks may be like other waterfowl (order Anseriformes), which are comparatively tolerant to embryo mortality from polychlorinated dibenzo-p-dioxins and dibenzofurans when exposed by egg injection. ?? 2008 US Government.

Stage-dependent toxicity of bisphenol a on Rhinella arenarum (anura, bufonidae) embryos and larvae.

PubMed

Wolkowicz, Ianina R Hutler; Herkovits, Jorge; Pérez Coll, Cristina S

2014-02-01

The acute and chronic toxicity of bisphenol A (BPA) was evaluated on the common South American toad Rhinella arenarum embryos and larvae by means of continuous and pulse exposure treatments. Embryos were treated continuously from early blastula (S.4) up to complete operculum (S.25), during early larval stages and by means of 24 h pulse exposures of BPA in concentrations ranging between 1.25 and 40 mg L(-1) , in order to evaluate the susceptibility to this compound in different developmental stages. For lethal effects, S.25 was the most sensitive and gastrula was the most resistant to BPA. The Teratogenic Index for neurula, the most sensitive embryonic stage for sublethal effects was 4.7. The main morphological alterations during early stages were: delayed or arrested development, reduced body size, persistent yolk plug, microcephaly, axial/tail flexures, edemas, blisters, waving fin, underdeveloped gills, mouth malformations, and cellular dissociation. BPA caused a remarkable narcotic effect from gill circulation stage (S.20) onwards in all the organisms exposed after 3 h of treatment with 10 mg L(-1) BPA. After recovering, the embryos exhibited scarce response to stimuli, erratic or circular swimming, and spasmodic contractions from 5 mg L(-1) onwards. Our results highlight the lethal and sublethal effectsof BPA on R. arenarum embryos and larvae, in the last case both at structural and functional levels. Copyright © 2011 Wiley Periodicals, Inc., A Wiley Company.

Effects of ammonium-based ionic liquids and 2,4-dichlorophenol on the phospholipid fatty acid composition of zebrafish embryos.

PubMed

Piotrowska, Aleksandra; Syguda, Anna; Wyrwas, Bogdan; Chrzanowski, Lukasz; Luckenbach, Till; Heipieper, Hermann J

2018-01-01

Ionic liquids consisting of a combination of herbicidal anions with a quaternary ammonium cation act as efficient herbicides, which are under consideration to be used in the agriculture. In the present study, we used embryos of the zebrafish (Danio rerio) as a model to assess the toxic potential of ammonium-based ionic liquids for aquatic organisms. As we assumed interference of the partially hydrophobic ionic liquid cation with lipids, we investigated the adaptation response in the lipid composition of the zebrafish embryos, triggered by the ionic compound. Therefore, the impact of ammonium-based ionic liquids with different lengths of the alkyl chain ([C6,C6,C1,C1N][Br], [C8,C8,C1,C1N][Br]) on the phospholipid fatty acid (PLFA) profile of zebrafish embryos up to 72 hours post fertilization (hpf) was examined. Furthermore, the changes in the unsaturation index (UI) of PLFAs, as the sum parameter of membrane fluidity in eukaryotic cells, were presented. The PLFA's UI in the zebrafish embryos upon exposure to quaternary ammonium salts was compared to the UI of the embryos upon exposure to nonionic 2,4-dichlorophenol, which has a similar hydrophobicity but is structurally different to [C8,C8,C1,C1N][Br]. It was shown that for ammonium-based ionic liquid precursors non-specific mode of action occurs and the toxic effect on lipid composition of zebrafish embryos can be well predicted based on chemical properties, like hydrophobicity. Furthermore, the changes in PLFAs, expressed by the UI, can be useful to study toxic effects of organic contamination. However, for zebrafish embryos, after ionic liquids and 2,4-DCP exposure, the changes were observed at high lethal concentrations, which caused the incidence of lethality of 30 and 50% of a group of test animals.

Effects of ammonium-based ionic liquids and 2,4-dichlorophenol on the phospholipid fatty acid composition of zebrafish embryos

PubMed Central

Piotrowska, Aleksandra; Syguda, Anna; Wyrwas, Bogdan; Chrzanowski, Lukasz; Luckenbach, Till

2018-01-01

Ionic liquids consisting of a combination of herbicidal anions with a quaternary ammonium cation act as efficient herbicides, which are under consideration to be used in the agriculture. In the present study, we used embryos of the zebrafish (Danio rerio) as a model to assess the toxic potential of ammonium-based ionic liquids for aquatic organisms. As we assumed interference of the partially hydrophobic ionic liquid cation with lipids, we investigated the adaptation response in the lipid composition of the zebrafish embryos, triggered by the ionic compound. Therefore, the impact of ammonium-based ionic liquids with different lengths of the alkyl chain ([C6,C6,C1,C1N][Br], [C8,C8,C1,C1N][Br]) on the phospholipid fatty acid (PLFA) profile of zebrafish embryos up to 72 hours post fertilization (hpf) was examined. Furthermore, the changes in the unsaturation index (UI) of PLFAs, as the sum parameter of membrane fluidity in eukaryotic cells, were presented. The PLFA’s UI in the zebrafish embryos upon exposure to quaternary ammonium salts was compared to the UI of the embryos upon exposure to nonionic 2,4-dichlorophenol, which has a similar hydrophobicity but is structurally different to [C8,C8,C1,C1N][Br]. It was shown that for ammonium-based ionic liquid precursors non-specific mode of action occurs and the toxic effect on lipid composition of zebrafish embryos can be well predicted based on chemical properties, like hydrophobicity. Furthermore, the changes in PLFAs, expressed by the UI, can be useful to study toxic effects of organic contamination. However, for zebrafish embryos, after ionic liquids and 2,4-DCP exposure, the changes were observed at high lethal concentrations, which caused the incidence of lethality of 30 and 50% of a group of test animals. PMID:29342167

Development of a general baseline toxicity QSAR model for the fish embryo acute toxicity test.

PubMed

Klüver, Nils; Vogs, Carolina; Altenburger, Rolf; Escher, Beate I; Scholz, Stefan

2016-12-01

Fish embryos have become a popular model in ecotoxicology and toxicology. The fish embryo acute toxicity test (FET) with the zebrafish embryo was recently adopted by the OECD as technical guideline TG 236 and a large database of concentrations causing 50% lethality (LC 50 ) is available in the literature. Quantitative Structure-Activity Relationships (QSARs) of baseline toxicity (also called narcosis) are helpful to estimate the minimum toxicity of chemicals to be tested and to identify excess toxicity in existing data sets. Here, we analyzed an existing fish embryo toxicity database and established a QSAR for fish embryo LC 50 using chemicals that were independently classified to act according to the non-specific mode of action of baseline toxicity. The octanol-water partition coefficient K ow is commonly applied to discriminate between non-polar and polar narcotics. Replacing the K ow by the liposome-water partition coefficient K lipw yielded a common QSAR for polar and non-polar baseline toxicants. This developed baseline toxicity QSAR was applied to compare the final mode of action (MOA) assignment of 132 chemicals. Further, we included the analysis of internal lethal concentration (ILC 50 ) and chemical activity (La 50 ) as complementary approaches to evaluate the robustness of the FET baseline toxicity. The analysis of the FET dataset revealed that specifically acting and reactive chemicals converged towards the baseline toxicity QSAR with increasing hydrophobicity. The developed FET baseline toxicity QSAR can be used to identify specifically acting or reactive compounds by determination of the toxic ratio and in combination with appropriate endpoints to infer the MOA for chemicals. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preimplantation death of xenomitochondrial mouse embryo harbouring bovine mitochondria

PubMed Central

Kawahara, Manabu; Koyama, Shiori; Iimura, Satomi; Yamazaki, Wataru; Tanaka, Aiko; Kohri, Nanami; Sasaki, Keisuke; Takahashi, Masashi

2015-01-01

Mitochondria, cellular organelles playing essential roles in eukaryotic cell metabolism, are thought to have evolved from bacteria. The organization of mtDNA is remarkably uniform across species, reflecting its vital and conserved role in oxidative phosphorylation (OXPHOS). Our objectives were to evaluate the compatibility of xenogeneic mitochondria in the development of preimplantation embryos in mammals. Mouse embryos harbouring bovine mitochondria (mtB-M embryos) were prepared by the cell-fusion technique employing the haemagglutinating virus of Japan (HVJ). The mtB-M embryos showed developmental delay at embryonic days (E) 3.5 after insemination. Furthermore, none of the mtB-M embryos could implant into the maternal uterus after embryo transfer, whereas control mouse embryos into which mitochondria from another mouse had been transferred developed as well as did non-manipulated embryos. When we performed quantitative PCR (qPCR) of mouse and bovine ND5, we found that the mtB-M embryos contained 8.3% of bovine mitochondria at the blastocyst stage. Thus, contamination with mitochondria from another species induces embryonic lethality prior to implantation into the maternal uterus. The heteroplasmic state of these xenogeneic mitochondria could have detrimental effects on preimplantation development, leading to preservation of species-specific mitochondrial integrity in mammals. PMID:26416548

The C. elegans homolog of Drosophila Lethal giant larvae functions redundantly with PAR-2 to maintain polarity in the early embryo.

PubMed

Beatty, Alexander; Morton, Diane; Kemphues, Kenneth

2010-12-01

Polarity is essential for generating cell diversity. The one-cell C. elegans embryo serves as a model for studying the establishment and maintenance of polarity. In the early embryo, a myosin II-dependent contraction of the cortical meshwork asymmetrically distributes the highly conserved PDZ proteins PAR-3 and PAR-6, as well as an atypical protein kinase C (PKC-3), to the anterior. The RING-finger protein PAR-2 becomes enriched on the posterior cortex and prevents these three proteins from returning to the posterior. In addition to the PAR proteins, other proteins are required for polarity in many metazoans. One example is the conserved Drosophila tumor-suppressor protein Lethal giant larvae (Lgl). In Drosophila and mammals, Lgl contributes to the maintenance of cell polarity and plays a role in asymmetric cell division. We have found that the C. elegans homolog of Lgl, LGL-1, has a role in polarity but is not essential. It localizes asymmetrically to the posterior of the early embryo in a PKC-3-dependent manner, and functions redundantly with PAR-2 to maintain polarity. Furthermore, overexpression of LGL-1 is sufficient to rescue loss of PAR-2 function. LGL-1 negatively regulates the accumulation of myosin (NMY-2) on the posterior cortex, representing a possible mechanism by which LGL-1 might contribute to polarity maintenance.

The effects of neonicotinoid exposure on embryonic development and organ mass in northern bobwhite quail (Colinus virginianus).

PubMed

Gobeli, Amanda; Crossley, Dane; Johnson, Jeff; Reyna, Kelly

2017-05-01

Since their emergence in the early 1990s, neonicotinoid use has increased exponentially to make them the world's most prevalent insecticides. Although there has been considerable research concerning the lethality of neonicotinoids, their sub-lethal and developmental effects are still being explored, especially with regard to non-mammalian species. The goal of this research was to investigate the effects of the neonicotinoid imidacloprid on the morphological and physiological development of northern bobwhite quail (Colinus virginianus). Bobwhite eggs (n=390) were injected with imidacloprid concentrations of 0 (sham), 10, 50, 100, and 150mg/kg of egg mass, which was administered at day 0 (pre-incubation), 3, 6, 9, or 12 of growth. Embryos were dissected, weighed, staged, and examined for any overt structural deformities after 19days of incubation. The mass of the embryonic heart, liver, lungs and kidneys was also recorded. The majority of treatments produced no discernible differences in embryo morphology; however, in some instances, embryos were subject to increased frequency of anatomical deformity and altered organ masses. Some impacts were more pronounced in specific dosing periods, implying that there may be critical windows of development when embryos are more susceptible to neonicotinoid exposure. This investigation suggests that imidacloprid has the potential to impact bobwhite quail embryonic development and chick survival. Copyright © 2017 Elsevier Inc. All rights reserved.

Sediment-contact fish embryo toxicity assay with Danio rerio to assess particle-bound pollutants in the Tietê River Basin (São Paulo, Brazil).

PubMed

Rocha, Paula Suares; Bernecker, Conny; Strecker, Ruben; Mariani, Carolina Fiorillo; Pompêo, Marcelo Luiz Martins; Storch, Volker; Hollert, Henner; Braunbeck, Thomas

2011-10-01

The Tietê River and its tributary Pinheiros River receive a highly complex organic and inorganic pollutants load from sanitary sewage and industrial sources, as well as agricultural and agroindustrial activities. The aim of the present study was to evaluate the embryotoxic and teratogenic effects of sediments from selected locations in the Tietê River Basin by means of the sediment contact embryo toxicity assay with Danio rerio, in order to provide a comprehensive and realistic insight into the bioavailable hazard potential of these sediment samples. Lethal and sub-lethal effects were recorded, and high embryo toxicity could be found in the samples not only in the vicinity of the megacity São Paulo (Billings reservoir and Pinheiros River samples), but also downstream (in the reservoirs Barra Bonita, Promissão and Três Irmãos). Results confirm that most toxicity is due to the discharges of the metropolitan area of São Paulo. However, they also indicate additional sources of pollutants along the river course, probably from industrial, agricultural and agroindustrial residues, which contribute to the degradation of each area. The sediment contact fish embryo test showed to be powerful tool to detect embryo toxicity in sediments, not only by being a sensitive method, but also for taking into account bioavailability. This test provides an ecological highly realistic and relevant exposure scenario, and should therefore be added in ecotoxicological sediment quality assessments. Copyright © 2011 Elsevier Inc. All rights reserved.

Developmental toxicity and risk assessment of nonylphenol to the South American toad, Rhinella arenarum.

PubMed

Mariel, Aronzon Carolina; Alejandra, Babay Paola; Silvia, Pérez Coll Cristina

2014-09-01

The toxicity of Nonylphenol, an emerging pollutant, on the common South American toad Rhinella arenarum was stage and time dependent, thus Median Lethal Concentrations (LC50) for acute (96h), short-term chronic (168h) and chronic exposure (336h) were 1.06; 0.96 and 0.17mgNP/L from embryonic period (S.4), whereas for exposure from larvae (S.25), LC50 remained constant at 0.37mgNP/L from 96h to 168h, decreasing to 0.11mgNP/L at 336h. NOEC-168h for exposure from embryos was 0.025mgNP/L. The Teratogenic Potential (NOEC-lethality/NOEC-sublethal effects) was 23 times higher than the threshold value, indicating a high risk for embryos to be malformed in absence of significant lethality and representing a threat for the species conservation. By comparing with other amphibians, the early development of R. arenarum was very sensitive to NP. The results highlight the relevance of extending the exposure time and look for the most sensitive stage in order to perform the bioassays for conservation purposes. Copyright © 2014 Elsevier B.V. All rights reserved.

Mutations in new cell cycle genes that fail to complement a multiply mutant third chromosome of Drosophila.

PubMed

White-Cooper, H; Carmena, M; Gonzalez, C; Glover, D M

1996-11-01

We have simultaneously screened for new alleles and second site mutations that fail to complement five cell cycle mutations of Drosphila carried on a single third chromosome (gnu, polo, mgr, asp, stg). Females that are either transheterozygous for scott of the antartic (scant) and polo, or homozygous for scant produce embryos that show mitotic defects. A maternal effect upon embryonic mitoses is also seen in embryos derived from females transheterozygous with helter skelter (hsk) and either mgr or asp. cleopatra (cleo), fails to complement asp but is not uncovered by a deficiency for asp. The mitotic phenotype of larvae heterozygous for cleo and the multiple mutant chromosome is similar to weak alleles of asp, but there are no defects in male meiosis. Mutations that failed to complement stg fell into two complementation groups corresponding to stg and a new gene noose. Three of the new stg alleles are early zygotic lethals, whereas the fourth is a pharate adult lethal allele that affects both mitosis and meiosis. Mutations in noose fully complement a small deficiency that removes stg, but when placed in trans to certain stg alleles, result in late lethality and mitotic abnormalities in larval brains.

Deficiency of Suppressor Enhancer Lin12 1 Like (SEL1L) in Mice Leads to Systemic Endoplasmic Reticulum Stress and Embryonic Lethality*

PubMed Central

Francisco, Adam B.; Singh, Rajni; Li, Shuai; Vani, Anish K.; Yang, Liu; Munroe, Robert J.; Diaferia, Giuseppe; Cardano, Marina; Biunno, Ida; Qi, Ling; Schimenti, John C.; Long, Qiaoming

2010-01-01

Stress in the endoplasmic reticulum (ER) plays an important causal role in the pathogenesis of several chronic diseases such as Alzheimer, Parkinson, and diabetes mellitus. Insight into the genetic determinants responsible for ER homeostasis will greatly facilitate the development of therapeutic strategies for the treatment of these debilitating diseases. Suppressor enhancer Lin12 1 like (SEL1L) is an ER membrane protein and was thought to be involved in the quality control of secreted proteins. Here we show that the mice homozygous mutant for SEL1L were embryonic lethal. Electron microscopy studies revealed a severely dilated ER in the fetal liver of mutant embryos, indicative of alteration in ER homeostasis. Consistent with this, several ER stress responsive genes were significantly up-regulated in the mutant embryos. Mouse embryonic fibroblast cells deficient in SEL1L exhibited activated unfolded protein response at the basal state, impaired ER-associated protein degradation, and reduced protein secretion. Furthermore, markedly increased apoptosis was observed in the forebrain and dorsal root ganglions of mutant embryos. Taken together, our results demonstrate an essential role for SEL1L in protein quality control during mouse embryonic development. PMID:20197277

Deficiency of suppressor enhancer Lin12 1 like (SEL1L) in mice leads to systemic endoplasmic reticulum stress and embryonic lethality.

PubMed

Francisco, Adam B; Singh, Rajni; Li, Shuai; Vani, Anish K; Yang, Liu; Munroe, Robert J; Diaferia, Giuseppe; Cardano, Marina; Biunno, Ida; Qi, Ling; Schimenti, John C; Long, Qiaoming

2010-04-30

Stress in the endoplasmic reticulum (ER) plays an important causal role in the pathogenesis of several chronic diseases such as Alzheimer, Parkinson, and diabetes mellitus. Insight into the genetic determinants responsible for ER homeostasis will greatly facilitate the development of therapeutic strategies for the treatment of these debilitating diseases. Suppressor enhancer Lin12 1 like (SEL1L) is an ER membrane protein and was thought to be involved in the quality control of secreted proteins. Here we show that the mice homozygous mutant for SEL1L were embryonic lethal. Electron microscopy studies revealed a severely dilated ER in the fetal liver of mutant embryos, indicative of alteration in ER homeostasis. Consistent with this, several ER stress responsive genes were significantly up-regulated in the mutant embryos. Mouse embryonic fibroblast cells deficient in SEL1L exhibited activated unfolded protein response at the basal state, impaired ER-associated protein degradation, and reduced protein secretion. Furthermore, markedly increased apoptosis was observed in the forebrain and dorsal root ganglions of mutant embryos. Taken together, our results demonstrate an essential role for SEL1L in protein quality control during mouse embryonic development.

Incomplete development of the spleen and the deformity in the chimeras between asplenic mutant (Dominant hemimelia) and normal mice.

PubMed

Suto, J; Wakayama, T; Imamura, K; Goto, S; Fukuta, K

1995-08-01

The semidominant gene Dh (Dominant hemimelia) induces skeletal and visceral abnormalities of various degrees and failure of the spleen in mice. The homozygous individual (Dh/Dh) seems to be lethal. The present experiment was designed to investigate the ability Dh cells to form a spleen and the genesis of the hind limb malformations by Dh/Dh and Dh/+ cells in chimeric mice. The Dh/Dh and Dh/+ embryos were produced in the F2 progeny of a cross between inbred strains of Dh/+ and DDD mice. They were aggregated with C3H/He or C57BL/6 embryos to make chimeras. Identification of Dh/Dh or Dh/+ embryos was carried out by Pep-3, and chimerism was analyzed by Gpi-1. Of 25 chimeras carrying the Dh gene, four mice formed a small spleen, two mice had a vestigial spleen, and the others no spleen. The tissues of the incompletely developed spleens were normal histologically and Dh cells were involved in the tissues of the spleen. In the chimeric mice, hindlimb malformation by the Dh gene was reduced in severity and the lethality of the homozygote (Dh/Dh) was rescued.

CHILD syndrome in a boy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Happle, R.; Effendy, I., Megahed, M.; Orlow, S.J.

CHILD syndrome (congential hemidysplasia with ichthyosiform nevus and limb defects) occurs, as a rule, exclusively in girls because of the underlying X-linked gene exerts a lethal effect on male embryos. In this report the characteristic manifestations of CHILD syndrome are described in a 2-year-old boy with a normal chromosome constitution 46,XY. This exceptional case is best explained by the assumption of an early somatic mutation and thus compatible with the concept of X-linked dominant male-lethal inheritance of this trait. 18 refs., 6 figs.

Sensitivity of embryos of chicken, domestic duck, and common eider duck to polychlorinated and non-halogenated aromatic hydrocarbons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brunstroem, B.

Embryos of chicken (Gallus domesticus), domestic duck (Anas platyrhynchos), and common eider duck (Somateria mollissima) were exposed in ovo to PCBs and to polycyclic aromatic hydrocarbons. Two coplanar PCBs, 3,3{prime},4,4{prime}-tetrachlorobiphenyl (PCB {number_sign}77) and 3,3{prime},4,4{prime},5-pentachlorobiphenyl (PCB {number_sign}126), were considerably more lethal and potent as inducers of 7-ethoxyresorufin O-deethylase (EROD) in chicken embryos (Gallus domesticus) than in embryos of the other two species. In chicken embryos, these compounds caused edema and eye and beak deformities. An artificial mixture of 18 PAHs which all have been detected in environmental samples, was slightly more toxic to embryos of the domestic duck and the commonmore » eider duck than to chicken embryos. The most potent compound in the mixture was benzo(k)fluoranthene. When chicken embryo livers were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in vitro, EROD was induced by very low concentrations and the EC{sub 50} value obtained was 5 {times} 10{sup {minus}12} M. Livers from embryos of eider ducks and domestic ducks were 2--4 orders of magnitude less responsive to TCDD than chicken embryo livers in terms of EROD induction in vitro.« less

O-polysaccharide is important for Salmonella Pullorum survival in egg albumen, and virulence and colonization in chicken embryos.

PubMed

Guo, Rongxian; Li, Zhuoyang; Jiao, Yang; Geng, Shizhong; Pan, Zhiming; Chen, Xiang; Li, Qiuchun; Jiao, Xinan

2017-10-01

The pathogen Salmonella Pullorum is the causative agent of persistent systemic infection of poultry, leading to economic losses in developing countries due to morbidity, mortality and reduction in egg production. These infections may result in vertical transmission to eggs or progeny. Limited information is available regarding the mechanisms involved in the survival of Salmonella Pullorum in egg albumen and developing chicken embryos. Hence, we investigated the role of O-polysaccharide in the contamination of eggs and the colonization of chicken embryos. Compared with the wild-type strain, the isogenic waaL mutant exhibited an O-antigen-deficient rough phenotype, and increased sensitivity to egg albumen and chicken serum, as well as reduced adherence to DF-1 cells. Infection with Salmonella Pullorum lacking O-polysaccharide resulted in significantly reduced embryo lethality and bacterial colonization. These results suggest that O-polysaccharide is essential for Salmonella Pullorum colonization in eggs, both post-lay and developing embryos. The chicken embryo infection model could be used to characterize the interaction between Salmonella Pullorum and developing embryos, and it will also contribute to the development of more rational vaccines to protect laying hens and embryos.

In vitro function of the aryl hydrocarbon receptor predicts in ...

EPA Pesticide Factsheets

Differences in sensitivity to dioxin-like compounds (DLCs) among species and taxa presents a major challenge to ecological risk assessments. Activation of the aryl hydrocarbon receptor (AHR) regulates adverse effects associated with exposure to DLCs in vertebrates. Prior investigations demonstrated that sensitivity to activation of the AHR1 (50% effect concentration; EC50) in an in vitro luciferase reporter gene (LRG) assay was predictive of the sensitivity of embryos (lethal dose to cause 50% lethality; LD50) across all species of birds for all DLCs. However, nothing was known about whether sensitivity to activation of the AHR is predictive of sensitivity of embryos of fishes to DLCs. Therefore, this study investigated in vitro sensitivities of AHR1s and AHR2s to the model DLC, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), among eight species of fish of known sensitivities of embryos to TCDD. AHR1s and AHR2s of all fishes were activated by TCDD in vitro. There was no significant linear relationship between in vitro sensitivity of AHR1 and in vivo sensitivity among the investigated fishes (R2 = 0.33, p = 0.23). However, there was a significant linear relationship between in vitro sensitivity of AHR2 and in vivo sensitivity among the investigated fishes (R2 = 0.97, p = < 0.0001). The linear relationship between in vitro sensitivity of AHR2 and in vivo sensitivity of embryos among fishes was compared to the previously generated linear relationship between in vitro s

CTCF knockout reveals an essential role for this protein during the zebrafish development.

PubMed

Carmona-Aldana, Francisco; Zampedri, Cecilia; Suaste-Olmos, Fernando; Murillo-de-Ozores, Adrián; Guerrero, Georgina; Arzate-Mejía, Rodrigo; Maldonado, Ernesto; Navarro, Rosa; Chimal-Monroy, Jesús; Recillas-Targa, Félix

2018-05-01

Chromatin regulation and organization are essential processes that regulate gene activity. The CCCTC-binding factor (CTCF) is a protein with different and important molecular functions related with chromatin dynamics. It is conserved since invertebrates to vertebrates, posing it as a factor with an important role in the physiology. In this work, we aimed to understand the distribution and functional relevance of CTCF during the embryonic development of the zebrafish (Danio rerio). We generated a zebrafish specific anti-Ctcf antibody, and found this protein to be ubiquitous, through different stages and tissues. We used the CRISPR-Cas9 system to induce molecular alterations in the locus. This resulted in early lethality. We delayed the lethality performing knockdown morpholino experiments, and found an aberrant embryo morphology involving malformations in structures through all the length of the embryo. These phenotypes were rescued with human CTCF mRNA injections, showing the specificity of the morpholinos and a partial functional conservation between the fish and the human proteins. Lastly, we found that the pro-apoptotic genes p53 and bbc3/PUMA are deregulated in the ctcf morpholino-injected embryos. In conclusion, CTCF is a ubiquitous factor during the zebrafish development, which regulates the correct formation of different structures of the embryo, and its deregulation impacts on essential cell survival genes. Overall, this work provides a basis to look for the particular functions of CTCF in the different developing tissues and organs of the zebrafish. Copyright © 2018. Published by Elsevier B.V.

Mixture toxicity of water contaminants-effect analysis using the zebrafish embryo assay (Danio rerio).

PubMed

Schmidt, Susanne; Busch, Wibke; Altenburger, Rolf; Küster, Eberhard

2016-06-01

Three water contaminants were selected to be tested in the zebrafish embryo toxicity test (DarT) in order to investigate the sensitivity of the zebrafish embryo toxicity test with respect to mixture effect detection. The concentration-response curves for the observed effects lethality and hypo-pigmentation were calculated after an exposure of the embryos for 96 h with a fungicide (carbendazim), a plasticizer or propellent precursor (2,4-DNT: 2,4- dinitrotoluene) and an aromatic compound (AαC: 2-amino-9H-pyrido[2,3-b]indol), respectively. Follow-up mixture tests were based on the calculated LC50 or EC50 of the single compounds and combined effects were predicted according to the mixture concepts of concentration addition (CA) and independent action (IA). The order of toxicity for the single substances was carbendazim (LC50 = 1.25 μM) < AαC (LC50 = 8.16 μM) < 2,4-DNT (LC50 = 177.05 μM). For AαC and 2,4 DNT hypo-pigmentation was observed in addition (AαC EC50 = 1.81 μM; 2,4-DNT EC50 = 8.81 μM). Two binary and one ternary mixture were studied on lethality and one on hypo-pigmentation: 2,4-DNT/AαC (LC50 = 119.21 μM, EC50 = 5.37 μM), carbendazim/AαC (LC50 = 4.49 μM) and AαC/Carbendazim/2,4 DNT (LC50 = 108.62 μM). Results showed that the effects were in agreement with the CA model when substances were tested in mixtures. Therefore, in a reasonable worst case scenario substance combination effects in fish embryos were at maximum only prone to overestimation when using CA as the mixture concept. Copyright © 2016 Elsevier Ltd. All rights reserved.

ENDOCRINE DISRUPTING CONTAMINANTS AND ALLIGATOR EMBRYOS: A LESSON FROM WILDLIFE?

EPA Science Inventory

Many xenobiotic compounds introduced into the environment by human activity adversely affect wildlife. A number of these contaminants have been hypothesized to induce non lethal, multigenerational effects by acting as endocrine disrupting agents. One case is that of the alligator...

Alterations to Juvenile Zebrafish (Danio rerio) Swim Performance after Acute Embryonic Exposure to Sub-lethal Exposures of Hydraulic Fracturing Flowback and Produced Water.

PubMed

Folkerts, Erik J; Blewett, Tamzin A; He, Yuhe; Goss, Greg G

2017-12-01

Hydraulic fracturing flowback and produced water (FPW) is a wastewater produced during fracturing activities in an operating well which is hyper saline and chemically heterogeneous in nature, containing both anthropogenic and petrogenic chemicals. Determination of FPW associated toxicity to embryonic fish is limited, while investigation into how embryonic exposures may affect later life stages is not yet studied. Zebrafish embryos (24hrs post fertilization) were acutely exposed to 2.5% and 5% FPW fractions for either 24 or 48hrs and returned to freshwater. After either 24 or 48h exposures, embryos were examined for expression of 3 hypoxia related genes. Erythropoietin (epoa) but not hypoxia inducible factor (hif1aa) nor hemoglobin -ß chain (hbbe1.1) was up-regulated after either 24 or 48h FPW exposure. Surviving embryos were placed in freshwater and grown to a juvenile stage (60days post fertilization). Previously exposed zebrafish were analyzed for both swim performance (U crit and U max ) and aerobic capacity. Fish exposed to both sediment containing (FPW-S) or sediment free (FPW-SF) FPW displayed significantly reduced aerobic scope and U crit /U max values compared to control conditions. Our results collectively suggest that organics present in our FPW sample may be responsible for sub-lethal fitness and metabolic responses. We provide evidence supporting the theory that the cardio-respiratory system is impacted by FPW exposure. This is the first known research associating embryonic FPW exposures to sub-lethal performance related responses in later life fish stages. Copyright © 2017 Elsevier B.V. All rights reserved.

Developmental toxicity of p,p'-dichlorodiphenyltrichloroethane, 2,4,6-trinitrotoluene, their metabolites, and benzo[a]pyrene in Xenopus laevis embryos.

PubMed

Saka, Masahiro

2004-04-01

Since 1995, high incidences of deformed frogs have been documented in Kitakyushu, Japan. In this area, relatively high concentrations of DDT, trinitrotoluene (TNT), their metabolites (p,p'-dichlorodiphenyldichloroethylene [DDE], p,p'-dichlorodiphenyldichloroethane [DDD], 2-amino-4,6-dinitrotoluene [2ADNT], and 4-amino-2,6-dinitrotoluene [4ADNT]), and benzo[a]pyrene [BaP]) have been identified from field samples. I used a standardized assay with Xenopus laevis embryos (frog embryo teratogenesis assay--Xenopus, FETAX) to examine the developmental toxicity of these compounds. Both DDE and BaP were considered nearly nontoxic in embryonic development because they induced low (< 10%) mortality and malformation incidence even at the highest concentrations tested (DDE, 393 microM; BaP, 13.2 microM). The DDD (96-h median lethal concentration [LC50] = 44.1 microM, 96-h median effective concentration [EC50] for malformation = 14.9 microM) was more lethal and teratogenic than its parent compound, DDT (96-h LC50 = 101 microM, 96-h EC50 = 41.5 microM). Predominant symptoms observed were axial malformations (DDT and DDD) and irregular gut coiling (DDT). However, DDT and DDD should not act as major lethal or teratogenic toxicants in the aquatic environment within a short-term exposure via water because their 96-h LC50 and 96-h EC50 values were extremely high, considering their low solubility in water. The TNT (96-h LC50 = 16.7 microM) was more lethal than 2ADNT (96-h LC50 = 166 microM) or 4ADNT (96-h LC50 = 115 microM). Although 4ADNT (96-h EC50 = 85.8 microM) induced various tadpole malformations, it was a weak teratogen compared with TNT (96-h EC50 = 9.78 microM) and 2ADNT (96-h EC50 = 16.9 microM). The most typical malformations observed were axial malformations, eye abnormalities (TNT), edema, and irregular gut coiling (2ADNT and 4ADNT). The 96-h LC50 and 96-h EC50 values of TNT, 2ADNT, and 4ADNT were lower than their saturated concentrations in water. Therefore, these nitroaromatic compounds may show lethal or teratogenic effects on aquatic animals if their habitats are severely contaminated with TNT.

Short-term exposure to low doses of rotenone induces developmental, biochemical, behavioral, and histological changes in fish.

PubMed

Melo, Karina Motta; Oliveira, Rhaul; Grisolia, Cesar Koppe; Domingues, Inês; Pieczarka, Julio Cesar; de Souza Filho, José; Nagamachi, Cleusa Yoshiko

2015-09-01

Rotenone, a natural compound derived from plants of the genera Derris and Lonchocarpus, is used worldwide as a pesticide and piscicide. This study aims to assess short-term toxicity of rotenone to early-life stages of the fish Danio rerio and Poecilia reticulata using a wide and integrative range of biomarkers (developmental, biochemical, behavioral, and histopathological). Moreover, the species sensitivity distribution (SSD) approach was used to compare rotenone acute toxicity to fish species. Toxicity tests were based on the OECD protocols, fish embryo toxicity test (for D. rerio embryos), and fish acute toxicity test (for P. reticulata juveniles). D. rerio embryos were used to estimate lethal concentrations and analyze embryonic and enzymatic alterations (activity of catalase, glutathione-S-transferase, and cholinesterase), while P. reticulata juveniles were used for the assessment of histological damage in the gills and liver. Rotenone induced significant mortality in zebrafish embryos with a 96-h lethal concentration 50% (LC50) = 12.2 μg/L. Rotenone was embryotoxic, affecting the development of D. rerio embryos, which showed cardiac edema; tail deformities; loss of equilibrium; and a general delay characterized by lack of tail detachment, delayed somite formation, yolk sac absorption, and lack of pigmentation. Biochemical biomarker inhibition was observed for concentrations ≥1 μg/L for CAT and glutathione-S-transferase (GST) and for cholinesterase (ChE) in concentration from 10 μg/L. Behavioral changes were observed for P. reticulata juveniles exposed to concentrations equal to or above 25 μg/L of rotenone; moreover, histological damage in the liver and gills of fish exposed to concentrations equal to or above 2.5 μg/L could be observed. A hazard concentration 5% (HC5) of 3.2 μg/L was estimated considering the acute toxicity data for different fish species (n = 49). Lethal and sublethal effects of rotenone raise a concern about its effects on nontarget fish species, especially because rotenone and its metabolite rotenolone are frequently reported in the microgram range in natural environments for several days after field applications. Rotenone should be used with caution. Given the high toxicity and wide range of sublethal effects here reported, further studies in a chronic exposure scenario are recommended.

Maternal aldehyde elimination during pregnancy preserves the fetal genome.

PubMed

Oberbeck, Nina; Langevin, Frédéric; King, Gareth; de Wind, Niels; Crossan, Gerry P; Patel, Ketan J

2014-09-18

Maternal metabolism provides essential nutrients to enable embryonic development. However, both mother and embryo produce reactive metabolites that can damage DNA. Here we discover how the embryo is protected from these genotoxins. Pregnant mice lacking Aldh2, a key enzyme that detoxifies reactive aldehydes, cannot support the development of embryos lacking the Fanconi anemia DNA repair pathway gene Fanca. Remarkably, transferring Aldh2(-/-)Fanca(-/-) embryos into wild-type mothers suppresses developmental defects and rescues embryonic lethality. These rescued neonates have severely depleted hematopoietic stem and progenitor cells, indicating that despite intact maternal aldehyde catabolism, fetal Aldh2 is essential for hematopoiesis. Hence, maternal and fetal aldehyde detoxification protects the developing embryo from DNA damage. Failure of this genome preservation mechanism might explain why birth defects and bone marrow failure occur in Fanconi anemia, and may have implications for fetal well-being in the many women in Southeast Asia that are genetically deficient in ALDH2. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Maternal Aldehyde Elimination during Pregnancy Preserves the Fetal Genome

PubMed Central

Oberbeck, Nina; Langevin, Frédéric; King, Gareth; de Wind, Niels; Crossan, Gerry P.; Patel, Ketan J.

2014-01-01

Summary Maternal metabolism provides essential nutrients to enable embryonic development. However, both mother and embryo produce reactive metabolites that can damage DNA. Here we discover how the embryo is protected from these genotoxins. Pregnant mice lacking Aldh2, a key enzyme that detoxifies reactive aldehydes, cannot support the development of embryos lacking the Fanconi anemia DNA repair pathway gene Fanca. Remarkably, transferring Aldh2−/−Fanca−/− embryos into wild-type mothers suppresses developmental defects and rescues embryonic lethality. These rescued neonates have severely depleted hematopoietic stem and progenitor cells, indicating that despite intact maternal aldehyde catabolism, fetal Aldh2 is essential for hematopoiesis. Hence, maternal and fetal aldehyde detoxification protects the developing embryo from DNA damage. Failure of this genome preservation mechanism might explain why birth defects and bone marrow failure occur in Fanconi anemia, and may have implications for fetal well-being in the many women in Southeast Asia that are genetically deficient in ALDH2. PMID:25155611

Acute toxicity and histopathological effects of naproxen in zebrafish (Danio rerio) early life stages.

PubMed

Li, Qian; Wang, Peipei; Chen, Ling; Gao, Hongwen; Wu, Lingling

2016-09-01

Zebrafish (Danio rerio) embryos and larvae were selected to investigate the potential risk and aquatic toxicity of a widely used pharmaceutical, naproxen. The acute toxicity of naproxen to embryos and larvae was measured, respectively. The histopathology was investigated in the liver of zebrafish larvae after 8-day embryo-larvae exposure to naproxen. The values of 96-h LC50 were 115.2 mg/L for embryos and 147.6 mg/L for larvae, indicating that zebrafish embryos were more sensitive than larvae to naproxen exposure. Large suites of symptoms were induced in zebrafish (D. rerio) early life stages by different dosages of naproxen, including hatching inhibition, lower heart rate, and morphological abnormalities. The most sensitive sub-lethal effect caused by naproxen was pericardial edema, the 72-h EC50 values of which for embryos and larvae were 98.3 and 149.0 mg/L, respectively. In addition, naproxen-treated zebrafish larvae exhibited histopathological liver damage, including swollen hepatocytes, vacuolar degeneration, and nuclei pycnosis. The results indicated that naproxen is a potential threat to aquatic organisms.

Effects of particle size and coating on nanoscale Ag and TiO₂ exposure in zebrafish (Danio rerio) embryos.

PubMed

Osborne, Olivia J; Johnston, Blair D; Moger, Julian; Balousha, Mohammed; Lead, Jamie R; Kudoh, Tetsuhiro; Tyler, Charles R

2013-12-01

Manufactured metal (oxide) nanoparticles are entering the aquatic environment with little understanding on their potential health impacts for exposed organisms. Adopting an integrative approach, we investigated effects of particle size and coating on biological responses for two of the most commonly used metal (oxide) nanoscale particles, silver (Ag) and titanium dioxide (TiO₂) in zebrafish embryos. Titanium dioxide nanoparticles (nominally, 4 nm, 10 nm, 30 nm and 134 nm) had little or no toxicity on the endpoints measured. Ag both in nano form (10 nm and 35 nm) and its larger counterpart (600-1600 nm) induced dose-dependent lethality and morphological defects, occurring predominantly during gastrula stage. Of the silver material tested 10 nm nanoparticles appeared to be the most toxic. Coating Ag nanoparticles with citrate or fulvic acid decreased toxicity significantly. In situ hybridisation analysis identified the yolk syncytial layer (YSL) as a target tissue for Ag-nano toxicity where there was a significant induction of the heavy metal stress response gene, metallothionein 2 (Mt2) at sub-lethal exposures. Coherent Anti-stroke Raman Scattering (CARS) microscopy provided no evidence for silver particles crossing the chorionic membrane in exposed embryos. Collectively, our data suggest that silver ions play a major role in the toxicity of Ag nanoparticles.

Analysis of Lethality and Malformations During Zebrafish (Danio rerio) Development.

PubMed

Raghunath, Azhwar; Perumal, Ekambaram

2018-01-01

The versatility offered by zebrafish (Danio rerio) makes it a powerful and an attractive vertebrate model in developmental toxicity and teratogenicity assays. Apart from the newly introduced chemicals as drugs, xenobiotics also induce abnormal developmental abnormalities and congenital malformations in living organisms. Over the recent decades, zebrafish embryo/larva has emerged as a potential tool to test teratogenicity potential of these chemicals. Zebrafish responds to compounds as mammals do as they share similarities in their development, metabolism, physiology, and signaling pathways with that of mammals. The methodology used by the different scientists varies enormously in the zebrafish embryotoxicity test. In this chapter, we present methods to assess lethality and malformations during zebrafish development. We propose two major malformations scoring systems: binomial and relative morphological scoring systems to assess the malformations in zebrafish embryos/larvae. Based on the scoring of the malformations, the test compound can be classified as a teratogen or a nonteratogen and its teratogenic potential is evaluated.

Mutants in the mouse NuRD/Mi2 component P66alpha are embryonic lethal.

PubMed

Marino, Susan; Nusse, Roel

2007-06-13

The NuRD/Mi2 chromatin complex is involved in histone modifications and contains a large number of subunits, including the p66 protein. There are two mouse and human p66 paralogs, p66alpha and p66beta. The functions of these genes are not clear, in part because there are no mutants available, except in invertebrate model systems. We made loss of function mutants in the mouse p66alpha gene (mp66alpha, official name Gatad2a, MGI:2384585). We found that mp66alpha is essential for development, as mutant embryos die around day 10 of embryogenesis. The gene is not required for normal blastocyst development or for implantation. The phenotype of mutant embryos and the pattern of gene expression in mutants are consistent with a role of mp66alpha in gene silencing. mp66alpha is an essential gene, required for early mouse development. The lethal phenotype supports a role in execution of methylated DNA silencing.

Oxygen supply limits the heat tolerance of lizard embryos.

PubMed

Smith, Colton; Telemeco, Rory S; Angilletta, Michael J; VandenBrooks, John M

2015-04-01

The mechanisms that set the thermal limits to life remain uncertain. Classically, researchers thought that heating kills by disrupting the structures of proteins or membranes, but an alternative hypothesis focuses on the demand for oxygen relative to its supply. We evaluated this alternative hypothesis by comparing the lethal temperature for lizard embryos developing at oxygen concentrations of 10-30%. Embryos exposed to normoxia and hyperoxia survived to higher temperatures than those exposed to hypoxia, suggesting that oxygen limitation sets the thermal maximum. As all animals pass through an embryonic stage where respiratory and cardiovascular systems must develop, oxygen limitation may limit the thermal niches of terrestrial animals as well as aquatic ones. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Zebrafish Embryo as an In Vivo Model for Behavioral and Pharmacological Characterization of Methylxanthine Drugs.

PubMed

Basnet, Ram Manohar; Guarienti, Michela; Memo, Maurizio

2017-03-09

Zebrafish embryo is emerging as an important tool for behavior analysis as well as toxicity testing. In this study, we compared the effect of nine different methylxanthine drugs using zebrafish embryo as a model. We performed behavioral analysis, biochemical assay and Fish Embryo Toxicity (FET) test in zebrafish embryos after treatment with methylxanthines. Each drug appeared to behave in different ways and showed a distinct pattern of results. Embryos treated with seven out of nine methylxanthines exhibited epileptic-like pattern of movements, the severity of which varied with drugs and doses used. Cyclic AMP measurement showed that, despite of a significant increase in cAMP with some compounds, it was unrelated to the observed movement behavior changes. FET test showed a different pattern of toxicity with different methylxanthines. Each drug could be distinguished from the other based on its effect on mortality, morphological defects and teratogenic effects. In addition, there was a strong positive correlation between the toxic doses (TC 50 ) calculated in zebrafish embryos and lethal doses (LD 50 ) in rodents obtained from TOXNET database. Taken together, all these findings elucidate the potentiality of zebrafish embryos as an in vivo model for behavioral and toxicity testing of methylxanthines and other related compounds.

Effects of 5-Fluorodeoxyuridine and Related Halogenated Pyrimidines on the Sand-Dollar Embryo

PubMed Central

Karnofsky, David A.; Basch, Ross S.

1960-01-01

The embryo of the sand-dollar (Echinarachnius parma) was exposed to various concentrations of fluorinated pyrimidines immediately after fertilization. FUDR (5-fluorodeoxyuridine) was most active, and a concentration of 2 to 4 mγ/10 cc. (0.8 to 1.6 x 10-6 m.eq./liter) blocked development at the early blastula stage. Larger doses interrupted development at the same stage. This effect was prevented by thymidine (TDR) and thymine (T); and these pyrimidines protected against many times the minimal lethal concentration of FUDR. TDR was active as a protective agent if added just before early blastula formation. The other fluorinated pyrimidines, 5-fluorouracil (FU), 5-fluorouridine (FUR), 5-fluorocytidine (FCR), 5-fluorodeoxycytidine (FCDR), and 5-fluoroorotic acid (FO), were also studied. These drugs produced effects on embryonic development similar to those seen with FUDR. The effective concentrations, however, varied greatly. T and TDR provided protection against these drugs, but in most cases they were not so effective as against FUDR. 5-Bromodeoxyurdine (BrUDR), beginning at the early blastula stage, caused a random pattern of embryonic death up to the pluteus stage. This drug has been shown to be incorporated into bacterial DNA. BrUDR protected embryos against the early lethal effects of FUDR presumably acting as a thymidine substitute, but the embryos died subsequently in a pattern similar to that seen with BrUDR alone. FUDR and BrUDR appear to inhibit the formation and alter the structure of DNA, respectively, distinctive effects whch may provide a means for studying the role of DNA in embryonic development. PMID:14404541

Effects of 5-fluorodeoxyuridine and related halogenated pyrimidines on the sand-dollar embryo.

PubMed

KARNOFSKY, D A; BASCH, R S

1960-02-01

The embryo of the sand-dollar (Echinarachnius parma) was exposed to various concentrations of fluorinated pyrimidines immediately after fertilization. FUDR (5-fluorodeoxyuridine) was most active, and a concentration of 2 to 4 mgamma/10 cc. (0.8 to 1.6 x 10(-6) m.eq./liter) blocked development at the early blastula stage. Larger doses interrupted development at the same stage. This effect was prevented by thymidine (TDR) and thymine (T); and these pyrimidines protected against many times the minimal lethal concentration of FUDR. TDR was active as a protective agent if added just before early blastula formation. The other fluorinated pyrimidines, 5-fluorouracil (FU), 5-fluorouridine (FUR), 5-fluorocytidine (FCR), 5-fluorodeoxycytidine (FCDR), and 5-fluoroorotic acid (FO), were also studied. These drugs produced effects on embryonic development similar to those seen with FUDR. The effective concentrations, however, varied greatly. T and TDR provided protection against these drugs, but in most cases they were not so effective as against FUDR. 5-Bromodeoxyurdine (BrUDR), beginning at the early blastula stage, caused a random pattern of embryonic death up to the pluteus stage. This drug has been shown to be incorporated into bacterial DNA. BrUDR protected embryos against the early lethal effects of FUDR presumably acting as a thymidine substitute, but the embryos died subsequently in a pattern similar to that seen with BrUDR alone. FUDR and BrUDR appear to inhibit the formation and alter the structure of DNA, respectively, distinctive effects whch may provide a means for studying the role of DNA in embryonic development.

Rac1 modulates cardiomyocyte adhesion during mouse embryonic development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abu-Issa, Radwan, E-mail: rabuissa@umich.edu

2015-01-24

Highlights: • Conditional knockout of Rac1 using Nkx2.5 Cre line is lethal at E13.5. • The myocardium of the mutant is thin and disorganized. • The phenotype is not due to cardiomyocyte low proliferation or apoptosis. • The phenotype is due to specific defect in cardiomyocyte adhesion. - Abstract: Rac1, a member of the Rho subfamily of small GTPases, is involved in morphogenesis and differentiation of many cell types. Here we define a role of Rac1 in cardiac development by specifically deleting Rac1 in the pre-cardiac mesoderm using the Nkx2.5-Cre transgenic driver line. Rac1-conditional knockout embryos initiate heart development normallymore » until embryonic day 11.5 (E11.5); their cardiac mesoderm is specified, and the heart tube is formed and looped. However, by E12.5-E13.5 the mutant hearts start failing and embryos develop edema and hemorrhage which is probably the cause for the lethality observed soon after. The hearts of Rac1-cKO embryos exhibit disorganized and thin myocardial walls and defects in outflow tract alignment. No significant differences of cardiomyocyte death or proliferation were found between developing control and mutant embryos. To uncover the role of Rac1 in the heart, E11.5 primary heart cells were cultured and analyzed in vitro. Rac1-deficient cardiomyocytes were less spread, round and loosely attached to the substrate and to each other implying that Rac1-mediated signaling is required for appropriate cell–cell and/or cellmatrix adhesion during cardiac development.« less

Defective ciliogenesis, embryonic lethality and severe impairment of the Sonic Hedgehog pathway caused by inactivation of the mouse complex A intraflagellar transport gene Ift122/Wdr10, partially overlapping with the DNA repair gene Med1/Mbd4

PubMed Central

Cortellino, Salvatore; Wang, Chengbing; Wang, Baolin; Bassi, Maria Rosaria; Caretti, Elena; Champeval, Delphine; Calmont, Amelie; Jarnik, Michal; Burch, John; Zaret, Kenneth; Larue, Lionel; Bellacosa, Alfonso

2009-01-01

Primary cilia are assembled and maintained by evolutionarily conserved intraflagellar transport (IFT) proteins that are involved in the coordinated movement of macromolecular cargo from the basal body to the cilium tip and back. The IFT machinery is organized in two structural complexes named complex A and complex B. Recently, inactivation in the mouse germline of Ift genes belonging to complex B revealed a requirement of ciliogenesis, or proteins involved in ciliogenesis, for Sonic Hedgehog (Shh) signaling in mammals. Here we report on a complex A mutant mouse, defective for the Ift122 gene. Ift122-null embryos show multiple developmental defects (exencephaly, situs viscerum inversus, delay in turning, hemorrhage and defects in limb development) that result in lethality. In the node, primary cilia were absent or malformed in homozygous mutant and heterozygous embryos, respectively. Impairment of the Shh pathway was apparent in both neural tube patterning (expansion of motoneurons and rostro-caudal level-dependent contraction or expansion of the dorso-lateral interneurons), and limb patterning (ectrosyndactyly). These phenotypes are distinct from both complex B IFT mutant embryos and embryos defective for the ciliary protein hennin/Arl13b, and suggest reduced levels of both Gli2/Gli3 activator and Gli3 repressor functions. We conclude that complex A and complex B factors play similar but distinct roles in ciliogenesis and Shh/Gli3 signaling. PMID:19000668

Reversible neuronal and muscular toxicity of caffeine in developing vertebrates.

PubMed

Rodriguez, Rufino S; Haugen, Rebecca; Rueber, Alexandra; Huang, Cheng-Chen

2014-06-01

This study utilizes zebrafish embryos to understand the cellular and molecular mechanisms of caffeine toxicity in developing vertebrate embryos. By using a high concentration of caffeine, we observed almost all the phenotypes that have been described in humans and/or in other animal models, including neural tube closure defect, jittery, touch insensitivity, and growth retardation as well as a drastic coiled body phenotype. Zebrafish embryos exposed to 5mM caffeine exhibited high frequent movement, 10 moves/min comparing with around 3 moves/min in control embryos, within half an hour post exposure (HPE). They later showed twitching, uncoordinated movement, and eventually severe body curvature by 6HPE. Exposure at later stages resulted in the same phenotypes but more posteriorly. Surprisingly, when caffeine was removed before 6HPE, the embryos were capable of recovering but still exhibited mild curvature and shorter bodies. Longer exposure caused irreversible body curvature and lethality. These results suggest that caffeine likely targets the neuro-muscular physiology in developing embryos. Immunohistochemistry revealed that the motorneurons in treated embryos developed shorter axons, abnormal branching, and excessive synaptic vesicles. Developing skeletal muscles also appeared smaller and lacked the well-defined boundaries seen in control embryos. Finally, caffeine increases the expression of genes involved in synaptic vesicle migration. In summary, our results provide molecular understanding of caffeine toxicity on developing vertebrate embryos. Published by Elsevier Inc.

PHOTOACTIVATED POLYCYCLIC AROMATIC HYDROCARBON TOXICITY IN MEDAKA (ORYZIAS LATIPES) EMBRYOS: RELEVANCE TO ENVIRONMENTAL RISK IN CONTAMINATED SITES

EPA Science Inventory

The hazard for photoactivated toxicity of polycyclic aromatic hydrocarbons (PAHs) has been clearly demonstrated; however, to our knowledge, the risk in contaminated systems has not been characterized. To address this question, a median lethal dose (LD50) for fluoranthene photoa...

AMBIENT SOLAR UV RADIATION CAUSES MORTALITY IN LARVAE OF THREE SPECIES OF RANA

EPA Science Inventory

Recent reports concerning the lethal effects of solar ultraviolet-B (UV-B) radiation on amphibians suggest that this stressor has the potential to impact some amphibian populations. In this study embryos and larvae of three anuran species, Rana pipiens, R. clamitans, and R. septe...

The Essential Gene EMB1611 Maintains Shoot Apical Meristem Function During Arabidopsis Development

USDA-ARS?s Scientific Manuscript database

The Arabidopsis thaliana genome contains hundreds of genes essential for seed development. Because null mutations in these genes cause embryo lethality, their specific molecular and developmental functions are largely unknown. Here, we identify a role for EMB1611/MEE22, an essential gene in Arabidop...

A 3-D QSAR-BASED IDENTIFICATION ALGORITHM FOR POTENTIAL ESTROGEN RECEPTOR LIGANDS

EPA Science Inventory

Recent reports concerning the lethal effects of solar ultraviolet-B (UV-B) radiation on amphibians suggest that this stressor has the potential to impact some amphibian populations. In this study embryos and larvae of three anuran species, Rana pipiens, R. clamitans, and R. septe...

Experimental hybridization among five species of lampreys from the Great Lakes

USGS Publications Warehouse

Piavis, George W.; Howell, John H.; Smith, Allen J.

1970-01-01

Experimental hybridization among five species of lampreys of the Upper Great Lakes routinely produced embryos through stage 8, and four crosses produced embryos to the larval stage. Three critical periods in the embryogenesis of hybrid lampreys were between stages 8 and 9, among stages 10, 11, and 12, and at stage 15. Embryonic development in hybrid lamprey embryos is basically identical to that of controls and is identical to that of the sea lamprey (Petromyzon marinus). Synchrony of development was observed among stages of viable hybrids and their controls but lethal hybrids generally did not maintain such synchrony. The derivative species concept has been confirmed experimentally. Questions have been raised concerning some evidence cited in behalf of the appropriateness of the concept that nonparasitic lampreys are the derived species.

Fatal herpesvirus hemorrhagic disease in wild and orphan asian elephants in southern India.

PubMed

Zachariah, Arun; Zong, Jian-Chao; Long, Simon Y; Latimer, Erin M; Heaggans, Sarah Y; Richman, Laura K; Hayward, Gary S

2013-04-01

Up to 65% of deaths of young Asian elephants (Elephas maximus) between 3 mo and 15 yr of age in Europe and North America over the past 20 yr have been attributed to hemorrhagic disease associated with a novel DNA virus called elephant endotheliotropic herpesvirus (EEHV). To evaluate the potential role of EEHV in suspected cases of a similar lethal acute hemorrhagic disease occurring in southern India, we studied pathologic tissue samples collected from field necropsies. Nine cases among both orphaned camp and wild Asian elephants were identified by diagnostic PCR. These were subjected to detailed gene subtype DNA sequencing at multiple PCR loci, which revealed seven distinct strains of EEHV1A and one of EEHV1B. Two orphan calves that died within 3 days of one another at the same training camp had identical EEHV1A DNA sequences, indicating a common epidemiologic source. However, the high level of EEHV1 subtype genetic diversity found among the other Indian strains matches that among over 30 EEHV1 strains that have been evaluated from Europe and North America. These results argue against the previous suggestions that this is just a disease of captive elephants and that the EEHV1 virus has crossed recently from African elephant (Loxodonta africana) hosts to Asian elephants. Instead, both the virus and the disease are evidently widespread in Asia and, despite the disease severity, Asian elephants appear to be the ancient endogenous hosts of both EEHV1A and EEHV1B.

A morphologic study of unfertilized oocytes and abnormal embryos in human in vitro fertilization.

PubMed

Bałakier, H; Casper, R F

1991-04-01

The morphology of human, unfertilized oocytes and abnormal embryos cultured in vitro for 48-72 hr was examined in an attempt to learn more about oocyte maturation and reproductive failure in in vitro fertilization (IVF). About 21% of the unfertilized oocytes were totally degenerated. The majority (56%) of the remaining oocytes was arrested at the metaphase II stage. They contained coherent chromosomal plates and had extruded the first polar body with nuclear material. About 13% of oocytes underwent spontaneous activation. In most of these cases the second polar body was retained and many subnuclei or one big nucleus was formed. Five percent of metaphase II oocytes penetrated by sperm were not activated, likely as a result of oocyte immaturity. The developmental ability of abnormal embryos was poor. Several one-cell-stage zygotes were arrested at the pronuclear stage or at mitosis of the first mitotic division. Polyspermic embryos, especially those which contained four or more pronuclei, did not divide or formed uneven, multinucleated blastomeres. However, some triploid and tetraploid embryos often appeared normal morphologically despite their lethal chromosomal abnormalities.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, Hyejin; Yoon, Min-Sik; Ryu, Kwon-Yul, E-mail: kyryu@uos.ac.kr

Highlights: •Proliferation capacity of Ubc{sup −/−} FLCs was reduced during culture in vitro. •Ubc is required for proliferation of both hepatocytes and bipotent FLEPCs. •Bipotent FLEPCs exhibit highest Ubc transcription and proliferation capacity. •Cell types responsible for Ubc{sup −/−} fetal liver developmental defect were identified. -- Abstract: We have previously demonstrated that disruption of polyubiquitin gene Ubc leads to mid-gestation embryonic lethality most likely due to a defect in fetal liver development, which can be partially rescued by ectopic expression of Ub. In a previous study, we assessed the cause of embryonic lethality with respect to the fetal liver hematopoieticmore » system. We confirmed that Ubc{sup −/−} embryonic lethality could not be attributed to impaired function of hematopoietic stem cells, which raises the question of whether or not FLECs such as hepatocytes and bile duct cells, the most abundant cell types in the liver, are affected by disruption of Ubc and contribute to embryonic lethality. To answer this, we isolated FLCs from E13.5 embryos and cultured them in vitro. We found that proliferation capacity of Ubc{sup −/−} cells was significantly reduced compared to that of control cells, especially during the early culture period, however we did not observe the increased number of apoptotic cells. Furthermore, levels of Ub conjugate, but not free Ub, decreased upon disruption of Ubc expression in FLCs, and this could not be compensated for by upregulation of other poly- or mono-ubiquitin genes. Intriguingly, the highest Ubc expression levels throughout the entire culture period were observed in bipotent FLEPCs. Hepatocytes and bipotent FLEPCs were most affected by disruption of Ubc, resulting in defective proliferation as well as reduced cell numbers in vitro. These results suggest that defective proliferation of these cell types may contribute to severe reduction of fetal liver size and potentially mid-gestation lethality of Ubc{sup −/−} embryos.« less

Evaluating the Zebrafish Embryo Toxicity Test for Pesticide ...

EPA Pesticide Factsheets

Given the numerous chemicals used in society, it is critical to develop tools for accurate and efficient evaluation of potential risks to human and ecological receptors. Fish embryo acute toxicity tests are 1 tool that has been shown to be highly predictive of standard, more resource-intensive, juvenile fish acute toxicity tests. However, there is also evidence that fish embryos are less sensitive than juvenile fish for certain types of chemicals, including neurotoxicants. The utility of fish embryos for pesticide hazard assessment was investigated by comparing published zebrafish embryo toxicity data from pesticides with median lethal concentration 50% (LC50) data for juveniles of 3 commonly tested fish species: rainbow trout, bluegill sunfish, and sheepshead minnow. A poor, albeit significant, relationship (r2 = 0.28; p < 0.05) was found between zebrafish embryo and juvenile fish toxicity when pesticides were considered as a single group, but a much better relationship (r2 = 0.64; p < 0.05) when pesticide mode of action was factored into an analysis of covariance. This discrepancy is partly explained by the large number of neurotoxic pesticides in the dataset, supporting previous findings that commonly used fish embryo toxicity test endpoints are particularly insensitive to neurotoxicants. These results indicate that it is still premature to replace juvenile fish toxicity tests with embryo-based tests such as the Organisation for Economic Co-op

The orphan receptor ALK7 and the Activin receptor ALK4 mediate signaling by Nodal proteins during vertebrate development.

PubMed

Reissmann, E; Jörnvall, H; Blokzijl, A; Andersson, O; Chang, C; Minchiotti, G; Persico, M G; Ibáñez, C F; Brivanlou, A H

2001-08-01

Nodal proteins have crucial roles in mesendoderm formation and left-right patterning during vertebrate development. The molecular mechanisms of signal transduction by Nodal and related ligands, however, are not fully understood. In this paper, we present biochemical and functional evidence that the orphan type I serine/threonine kinase receptor ALK7 acts as a receptor for mouse Nodal and Xenopus Nodal-related 1 (Xnr1). Receptor reconstitution experiments indicate that ALK7 collaborates with ActRIIB to confer responsiveness to Xnr1 and Nodal. Both receptors can independently bind Xnr1. In addition, Cripto, an extracellular protein genetically implicated in Nodal signaling, can independently interact with both Xnr1 and ALK7, and its expression greatly enhances the ability of ALK7 and ActRIIB to respond to Nodal ligands. The Activin receptor ALK4 is also able to mediate Nodal signaling but only in the presence of Cripto, with which it can also interact directly. A constitutively activated form of ALK7 mimics the mesendoderm-inducing activity of Xnr1 in Xenopus embryos, whereas a dominant-negative ALK7 specifically blocks the activities of Nodal and Xnr1 but has little effect on other related ligands. In contrast, a dominant-negative ALK4 blocks all mesoderm-inducing ligands tested, including Nodal, Xnr1, Xnr2, Xnr4, and Activin. In agreement with a role in Nodal signaling, ALK7 mRNA is localized to the ectodermal and organizer regions of Xenopus gastrula embryos and is expressed during early stages of mouse embryonic development. Therefore, our results indicate that both ALK4 and ALK7 can mediate signal transduction by Nodal proteins, although ALK7 appears to be a receptor more specifically dedicated to Nodal signaling.

The orphan receptor ALK7 and the Activin receptor ALK4 mediate signaling by Nodal proteins during vertebrate development

PubMed Central

Reissmann, Eva; Jörnvall, Henrik; Blokzijl, Andries; Andersson, Olov; Chang, Chenbei; Minchiotti, Gabriella; Persico, M. Graziella; Ibáñez, Carlos F.; Brivanlou, Ali H.

2001-01-01

Nodal proteins have crucial roles in mesendoderm formation and left–right patterning during vertebrate development. The molecular mechanisms of signal transduction by Nodal and related ligands, however, are not fully understood. In this paper, we present biochemical and functional evidence that the orphan type I serine/threonine kinase receptor ALK7 acts as a receptor for mouse Nodal and Xenopus Nodal-related 1 (Xnr1). Receptor reconstitution experiments indicate that ALK7 collaborates with ActRIIB to confer responsiveness to Xnr1 and Nodal. Both receptors can independently bind Xnr1. In addition, Cripto, an extracellular protein genetically implicated in Nodal signaling, can independently interact with both Xnr1 and ALK7, and its expression greatly enhances the ability of ALK7 and ActRIIB to respond to Nodal ligands. The Activin receptor ALK4 is also able to mediate Nodal signaling but only in the presence of Cripto, with which it can also interact directly. A constitutively activated form of ALK7 mimics the mesendoderm-inducing activity of Xnr1 in Xenopus embryos, whereas a dominant-negative ALK7 specifically blocks the activities of Nodal and Xnr1 but has little effect on other related ligands. In contrast, a dominant-negative ALK4 blocks all mesoderm-inducing ligands tested, including Nodal, Xnr1, Xnr2, Xnr4, and Activin. In agreement with a role in Nodal signaling, ALK7 mRNA is localized to the ectodermal and organizer regions of Xenopus gastrula embryos and is expressed during early stages of mouse embryonic development. Therefore, our results indicate that both ALK4 and ALK7 can mediate signal transduction by Nodal proteins, although ALK7 appears to be a receptor more specifically dedicated to Nodal signaling. PMID:11485994

Toxicity of effluents from gasoline stations oil-water separators to early life stages of zebrafish Danio rerio.

PubMed

Alves, Romulo Nepomuceno; Mariz, Célio Freire; Paulo, Driele Ventura de; Carvalho, Paulo S M

2017-07-01

Used petroleum hydrocarbons and gasoline stations runoff are significant sources of polycyclic aromatic hydrocarbons (PAHs) to aquatic ecosystems. Samples of the final effluent of oil-water-separators were collected at gasoline stations in the metropolitan region of Recife, Brazil, before release to sewage or rainwater systems. Effluent soluble fractions (ESF) were prepared and bioassays were performed according to the Fish Embryo Toxicity Test. The test involved exposing zebrafish Danio rerio embryos to dilutions of the ESFs for 96 h, with daily examination of lethality and sublethal morphological effects integrated through the General Morphology Score (GMS), based on the achievement of developmental hallmarks. Frequencies of abnormalities were recorded after exposures. ESF LC50-96h (lethal concentration to 50% of exposed embryos) in the most toxic effluent achieved 8.9% (v/v), equivalent to 11 μg phenanthrene equivalents L -1 . GMS scores indicated significantly delayed embryo-larval development at ESF dilutions of 10% and 20% from effluents of all gas stations. Major abnormalities detected after the 96 h exposure included the presence of a yolk sac not fully absorbed coupled with the lack of an inflated swim bladder, lack of both pectoral fins, and the failure to develop a protruding mouth. Effective equivalent PAH concentrations that induce a 50% frequency of larvae without an inflated swim bladder (EC50) were 4.9 μg phenanthrene L -1 , 21.8 μg naphthalene L -1 , and 34.1 μg chrysene L -1 . This study shows that PAHs in ESFs from gas stations oil water separators are toxic to zebrafish, contributing to the toxicity of urban storm waters. Copyright © 2017 Elsevier Ltd. All rights reserved.

AtCSLA7, a Cellulose Synthase-Like Putative Glycosyltransferase, Is Important for Pollen Tube Growth and Embryogenesis in Arabidopsis1

PubMed Central

Goubet, Florence; Misrahi, Audrey; Park, Soon Ki; Zhang, Zhinong; Twell, David; Dupree, Paul

2003-01-01

The cellulose synthase-like proteins are a large family of proteins in plants thought to be processive polysaccharide β-glycosyltransferases. We have characterized an Arabidopsis mutant with a transposon insertion in the gene encoding AtCSLA7 of the CSLA subfamily. Analysis of the transmission efficiency of the insertion indicated that AtCSLA7 is important for pollen tube growth. Moreover, the homozygous insertion was embryo lethal. A detailed analysis of seed developmental progression revealed that mutant embryos developed more slowly than wild-type siblings. The mutant embryos also showed abnormal cell patterning and they arrested at a globular stage. The defective embryonic development was associated with reduced proliferation and failed cellularization of the endosperm. AtCSLA7 is widely expressed, and is likely to be required for synthesis of a cell wall polysaccharide found throughout the plant. Our results suggest that this polysaccharide is essential for cell wall structure or for signaling during plant embryo development. PMID:12586879

Fundamental cryobiology of mouse ova and embryos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leibo, S. P.

An increasing fraction of mouse ova and embryos are killed as the rate at which they are cooled to -196/sup 0/C is increased. The survival of these cells depends not only on cooling rate, but also on the minimum subzero temperature to which the cells are cooled. Low temperature microscopy demonstrates that lethal cooling rates are coincident with those that produce intracellular ice formation, and that the lethal temperature appears to be that at which intracellular ice forms. Furthermore, the microscopy shows that ova do not dehydrate when cooled at rates that produce intracellular ice and cell death, but undergomore » substantial shrinkage when cooled at rates that produce little intracellular ice and high survival. Measurements of the water permeability of mouse ova and the temperature coefficient of that permeability can be used to test a mathematical model formulated to describe the kinetics of water loss at subzero temperatures from a hypothetical cell. The observed dehydration of ova cooled to subzero temperatures at given rates is approximately predicted by the mathematical model, although there is some quantitative discrepancy between the observed and calculated responses.« less

Enhanced malignant transformation is accompanied by increased survival recovery after ionizing radiation in Chinese hamster embryo fibroblasts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boothman, D.A.

Transformed Chinese hamster embryo fibroblasts (CHEF), which gradually increase in tumor-forming ability in nude mice, were isolated from normal diploid CHEF/18 cells. Transformed CHEF cells (i.e., T30-4 > 21-2M3 > 21-2 > normal CHEF/18) showed gradual increases in potentially lethal damage (PLD) survival recovery. {beta}-Lapachone and camptothecin, modulators of topoisomerase I (Topo I) activity, not only prevented survival recovery in normal as well as in tumor cells, but enhanced unscheduled DNA synthesis. These seemingly conflicting results are due to the fact that Topo I activity can be modulated by inhibitors to convert single-stranded DNA lesions into double-stranded breaks. Increases inmore » unscheduled DNA synthesis may result from a continual supply of free ends, on which DNA repair processes may act. Altering Topo I activity with modulators appears to increase X-ray lethality via a DNA lesion modification suicide pathway. Cells down-regulate Topo I immediately after ionizing radiation to prevent Topo I-mediated lesion modification and to enhance survival recovery. 16 refs., 3 figs., 1 tab.« less

Mutants in the Mouse NuRD/Mi2 Component P66α Are Embryonic Lethal

PubMed Central

Marino, Susan; Nusse, Roel

2007-01-01

Background The NuRD/Mi2 chromatin complex is involved in histone modifications and contains a large number of subunits, including the p66 protein. There are two mouse and human p66 paralogs, p66α and p66β. The functions of these genes are not clear, in part because there are no mutants available, except in invertebrate model systems. Methodology We made loss of function mutants in the mouse p66α gene (mp66α, official name Gatad2a, MGI:2384585). We found that mp66α is essential for development, as mutant embryos die around day 10 of embryogenesis. The gene is not required for normal blastocyst development or for implantation. The phenotype of mutant embryos and the pattern of gene expression in mutants are consistent with a role of mp66α in gene silencing. Conclusion mp66α is an essential gene, required for early mouse development. The lethal phenotype supports a role in execution of methylated DNA silencing. PMID:17565372

Carbon monoxide-induced suspended animation protects against hypoxic damage in Caenorhabditis elegans

PubMed Central

Nystul, Todd G.; Roth, Mark B.

2004-01-01

Oxygen deprivation is a major cause of cellular damage and death. Here we demonstrate that Caenorhabditis elegans embryos, which can survive both in anoxia (<0.001 kPa O2) by entering into suspended animation and in mild hypoxia (0.25-1 kPa O2) through a hypoxia-inducible factor 1-mediated response, cannot survive in intermediate concentrations of oxygen, between 0.01 and 0.1 kPa O2. Moreover, we show that carbon monoxide can protect C. elegans embryos against hypoxic damage in this sensitive range. Carbon monoxide can also rescue the hypoxia-sensitive mutant hif-1(ia04) from lethality in hypoxia. This work defines the oxygen tensions over which hypoxic damage occurs in C. elegans embryos and demonstrates that carbon monoxide can prevent this damage by inducing suspended animation. PMID:15184665

Developmental Toxicity of Diclofenac and Elucidation of Gene Regulation in zebrafish (Danio rerio)

NASA Astrophysics Data System (ADS)

Chen, Jia-Bin; Gao, Hong-Wen; Zhang, Ya-Lei; Zhang, Yong; Zhou, Xue-Fei; Li, Chun-Qi; Gao, Hai-Ping

2014-05-01

Environmental pollution by emerging contaminants, e.g. pharmaceuticals, has become a matter of widespread concern in recent years. We investigated the membrane transport of diclofenac and its toxic effects on gene expression and the development of zebrafish embryos. The association of diclofenac with the embryos conformed to the general partition model at low concentration, the partition coefficient being 0.0033 ml per embryo. At high concentration, the interaction fitted the Freundlich model. Most of the diclofenac remained in the extracellular aqueous solution with less than 5% interacting with the embryo, about half of which was adsorbed on the membranes while the rest entered the cytoplasm. Concentrations of diclofenac over 10.13 μM were lethal to all the embryos, while 3.78 μM diclofenac was teratogenic. The development abnormalities at 4 day post treatment (dpt) include shorter body length, smaller eye, pericardial and body edema, lack of liver, intestine and circulation, muscle degeneration, and abnormal pigmentation. The portion of the diclofenac transferred into the embryo altered the expression of certain genes, e.g. down-regulation of Wnt3a and Gata4 and up-regulation of Wnt8a. The alteration of expression of such genes or the regulation of downstream genes could cause defects in the cardiovascular and nervous systems.

Improved mutagen-testing systems in mice: Progress report, June 1, 1988--May 31, 1989

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roderick, T.H.

1989-01-01

In December we injected 20 mice with 250 mg/kg of ENU. Half of the mice were males of C57BL/6J and half were males of strains AEJ/GnRk. The strains were chosen to include a standard widely used strain (C57BL/6J) but also to include a strain (AEJ/GnRk) that has an unusually large litter size (mean = 10) to promote better survival of embryos with induced recessives. Sentinal females are in with the treated males to determine return to fertility of the injected males. All males will be mated with the new lethal test system. Lethal No. 1 has now been clearly determinedmore » to be just distal to the distal breakpoint of inversion In(1)1Rk. All other lethals, including the new lethal No. 8 are crossed with our specially constructed stocks for linkage analysis. Also, the lethals are being crossed with known recessive markers along the inverted segment to determine possible allelism. All lethals have been intercrossed to determine whether they complement each other. Wild type animals should not be recovered if the lethals are overlapping. In a new study we are examining the wild type animals from each of these crosses carefully for general phenotypic conformation, eye disorders, feet, body weight and gait. Although these lethals may be complementary, it is possible that some interactive effects could be produced in an animal doubly heterozygous for different deletions.« less

COMPARATIVE SENSITIVITY OF DIFFERENT LIFE-STAGES OF MEDAKA AND SALMONID FISHES TO 2,3,7,8-TCDD

EPA Science Inventory

The early life stages of fish are known to be more sensitive than the adults to the toxicological effects of 2,3,7,8-tetrachlorodibenzo(p)dioxin (TCDD). Embryo larval stages of medake, for example, experience 50% lethality when TCDD residues in the eggs are 1396 pg/g. By contrast...

Lethal and Sublethal Effects of the Herbicide Atrazine in the Early Stages of Development of Physalaemus gracilis (Anura: Leptodactylidae).

PubMed

Rutkoski, Camila F; Macagnan, Natani; Kolcenti, Cassiane; Vanzetto, Guilherme V; Sturza, Paola F; Hartmann, Paulo A; Hartmann, Marilia T

2018-05-01

Water sources used as reproductive sites by crying frog, Physalaemus gracilis, are extensively associated with agroecosystems in which the herbicide atrazine is employed. To evaluate the lethal and sublethal effects of atrazine commercial formulation, acute and chronic toxicity tests were performed in the embryonic phase and the beginning of the larval phase of P. gracilis. Tests were started on stage 19 of Gosner (Herpetologica 16:183-190, 1960) and performed in 24-well cell culture plates. Acute tests had a duration of 96 h with embryo mortality monitoring every 24 h. Chronic assays contemplated the transition from the embryonic to larval stages and lasted 168 h. Every 24 h the embryos/larvae were observed for mortality, mobility, and malformations. The LC50 of atrazine determined for P. gracilis embryos was 229.34 mg L -1 . The sublethal concentrations did not affect the development of the larvae but were observed effects on mobility and malformations, such as spasmodic contractions, reduced mobility, malformations in mouth and intestine, and edema arising. From 1 mg L -1 atrazine, the exposed larvae began to have changes in mobility and malformations. The atrazine commercial formulation has caused early life effects of P. gracilis that may compromise the survival of this species but at higher concentrations than recorded in the environment, so P. gracilis can be considered tolerant to this herbicide at environmentally relevant concentrations.

Optical tracking of embryonic vertebrates behavioural responses using automated time-resolved video-microscopy system

NASA Astrophysics Data System (ADS)

Walpitagama, Milanga; Kaslin, Jan; Nugegoda, Dayanthi; Wlodkowic, Donald

2016-12-01

The fish embryo toxicity (FET) biotest performed on embryos of zebrafish (Danio rerio) has gained significant popularity as a rapid and inexpensive alternative approach in chemical hazard and risk assessment. The FET was designed to evaluate acute toxicity on embryonic stages of fish exposed to the test chemical. The current standard, similar to most traditional methods for evaluating aquatic toxicity provides, however, little understanding of effects of environmentally relevant concentrations of chemical stressors. We postulate that significant environmental effects such as altered motor functions, physiological alterations reflected in heart rate, effects on development and reproduction can occur at sub-lethal concentrations well below than LC10. Behavioral studies can, therefore, provide a valuable integrative link between physiological and ecological effects. Despite the advantages of behavioral analysis development of behavioral toxicity, biotests is greatly hampered by the lack of dedicated laboratory automation, in particular, user-friendly and automated video microscopy systems. In this work we present a proof-of-concept development of an optical system capable of tracking embryonic vertebrates behavioral responses using automated and vastly miniaturized time-resolved video-microscopy. We have employed miniaturized CMOS cameras to perform high definition video recording and analysis of earliest vertebrate behavioral responses. The main objective was to develop a biocompatible embryo positioning structures that were suitable for high-throughput imaging as well as video capture and video analysis algorithms. This system should support the development of sub-lethal and behavioral markers for accelerated environmental monitoring.

Genetics of Lipid-Storage Management in Caenorhabditis elegans Embryos

PubMed Central

Schmökel, Verena; Memar, Nadin; Wiekenberg, Anne; Trotzmüller, Martin; Schnabel, Ralf; Döring, Frank

2016-01-01

Lipids play a pivotal role in embryogenesis as structural components of cellular membranes, as a source of energy, and as signaling molecules. On the basis of a collection of temperature-sensitive embryonic lethal mutants, a systematic database search, and a subsequent microscopic analysis of >300 interference RNA (RNAi)–treated/mutant worms, we identified a couple of evolutionary conserved genes associated with lipid storage in Caenorhabditis elegans embryos. The genes include cpl-1 (cathepsin L–like cysteine protease), ccz-1 (guanine nucleotide exchange factor subunit), and asm-3 (acid sphingomyelinase), which is closely related to the human Niemann-Pick disease–causing gene SMPD1. The respective mutant embryos accumulate enlarged droplets of neutral lipids (cpl-1) and yolk-containing lipid droplets (ccz-1) or have larger genuine lipid droplets (asm-3). The asm-3 mutant embryos additionally showed an enhanced resistance against C band ultraviolet (UV-C) light. Herein we propose that cpl-1, ccz-1, and asm-3 are genes required for the processing of lipid-containing droplets in C. elegans embryos. Owing to the high levels of conservation, the identified genes are also useful in studies of embryonic lipid storage in other organisms. PMID:26773047

Role of kinase-independent and -dependent functions of FAK in endothelial cell survival and barrier function during embryonic development.

PubMed

Zhao, Xiaofeng; Peng, Xu; Sun, Shaogang; Park, Ann Y J; Guan, Jun-Lin

2010-06-14

Focal adhesion kinase (FAK) is essential for vascular development as endothelial cell (EC)-specific knockout of FAK (conditional FAK knockout [CFKO] mice) leads to embryonic lethality. In this study, we report the differential kinase-independent and -dependent functions of FAK in vascular development by creating and analyzing an EC-specific FAK kinase-defective (KD) mutant knockin (conditional FAK knockin [CFKI]) mouse model. CFKI embryos showed apparently normal development through embryonic day (E) 13.5, whereas the majority of CFKO embryos died at the same stage. Expression of KD FAK reversed increased EC apoptosis observed with FAK deletion in embryos and in vitro through suppression of up-regulated p21. However, vessel dilation and defective angiogenesis of CFKO embryos were not rescued in CFKI embryos. ECs without FAK or expressing KD FAK showed increased permeability, abnormal distribution of vascular endothelial cadherin (VE-cadherin), and reduced VE-cadherin Y658 phosphorylation. Together, our data suggest that kinase-independent functions of FAK can support EC survival in vascular development through E13.5 but are insufficient for maintaining EC function to allow for completion of embryogenesis.

FATAL HERPESVIRUS HEMORRHAGIC DISEASE IN WILD AND ORPHAN ASIAN ELEPHANTS IN SOUTHERN INDIA

PubMed Central

Zachariah, Arun; Zong, Jian-Chao; Long, Simon Y.; Latimer, Erin M.; Heaggans, Sarah Y.; Richman, Laura K.; Hayward, Gary S.

2013-01-01

Up to 65% of deaths of young Asian elephants (Elephas maximus) between 3 mo and 15 yr of age in Europe and North America over the past 20 yr have been attributed to hemorrhagic disease associated with a novel DNA virus called elephant endotheliotropic herpesvirus (EEHV). To evaluate the potential role of EEHV in suspected cases of a similar lethal acute hemorrhagic disease occurring in southern India, we studied pathologic tissue samples collected from field necropsies. Nine cases among both orphaned camp and wild Asian elephants were identified by diagnostic PCR. These were subjected to detailed gene subtype DNA sequencing at multiple PCR loci, which revealed seven distinct strains of EEHV1A and one of EEHV1B. Two orphan calves that died within 3 days of one another at the same training camp had identical EEHV1A DNA sequences, indicating a common epidemiologic source. However, the high level of EEHV1 subtype genetic diversity found among the other Indian strains matches that among over 30 EEHV1 strains that have been evaluated from Europe and North America. These results argue against the previous suggestions that this is just a disease of captive elephants and that the EEHV1 virus has crossed recently from African elephant (Loxodonta africana) hosts to Asian elephants. Instead, both the virus and the disease are evidently widespread in Asia and, despite the disease severity, Asian elephants appear to be the ancient endogenous hosts of both EEHV1A and EEHV1B. PMID:23568914

Assessing the toxicity of sediments using the medaka embryo-larval assay and 2 other bioassays.

PubMed

Barhoumi, Badreddine; Clérandeau, Christelle; Landi, Laure; Pichon, Anaïk; Le Bihanic, Florane; Poirier, Dominique; Anschutz, Pierre; Budzinski, Hélène; Driss, Mohamed Ridha; Cachot, Jérôme

2016-09-01

Sediments are sinks for aquatic pollutants, and analyzing toxicity in such complex matrices is still challenging. To evaluate the toxicity of bioavailable pollutants accumulated in sediments from the Bizerte lagoon (Tunisia), a novel assay, the medaka embryo-larval assay by sediment contact, was applied. Japanese medaka (Oryzias latipes) embryos were incubated in direct contact with sediment samples up to hatching. Lethal and sublethal adverse effects were recorded in embryos and larvae up to 20 d postfertilization. Results from medaka embryo-larval assay were compared with cytotoxicity (Microtox®), genotoxicity (SOS chromotest), and pollutant content of sediments. The results highlight differences in the contamination profile and toxicity pattern between the different studied sediments. A significant correlation was shown between medaka embryo-larval assay by sediment contact and SOS chromotest responses and concentrations of most organic pollutants studied. No correlation was shown between pollutant levels and Microtox. According to the number of sediment samples detected as toxic, medaka embryo-larval assay by sediment contact was more sensitive than Microtox, which in turn was more sensitive than the SOS chromotest; and medaka embryo-larval assay by sediment contact allowed sediment toxicity assessment of moderately polluted sediments without pollutant extraction and using an ecologically realistic exposure scenario. Although medaka embryo-larval assay by sediment contact should be tested on a larger sample set, the results show that it is sensitive and convenient enough to monitor the toxicity of natural sediments. Environ Toxicol Chem 2016;35:2270-2280. © 2016 SETAC. © 2016 SETAC.

Vitrification-based cryopreservation of Drosophila embryos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schreuders, P.D.; Mazur, P.

1994-12-31

Currently, over 30,000 strains of Drosophila melanogaster are maintained by geneticists through regular transfer of breeding stocks. A more cost effective solution is to cryopreserve their embryos. Cooling and warming rates >10,000{degrees}C/min. are required to prevent chilling injury. To avoid the lethal intracellular ice normally produced at such high cooling rates, it is necessary to use {ge}50% (w/w) concentrations of glass-inducing solutes to vitrify the embryos. Differential scanning calorimetry (DSC) is used to develop and evaluate ethylene glycol and polyvinyl pyrrolidone based vitrification solutions. The resulting solution consists of 8.5M ethylene glycol + 10% polyvinylpyrrolidone in D-20 Drosophila culture medium.more » A two stage method is used for the introduction and concentration of these solutes within the embryo. The method reduces the exposure time to the solution and, consequently, reduces toxicity. Both DSC and freezing experiments suggest that, while twelve-hour embryos will vitrify using cooling rates >200{degrees}C/min., they will devitrify and be killed with even moderately rapid warming rates of {approximately}1,900{degrees}C/min. Very rapid warming ({approximately}100,000{degrees}C/min.) results in variable numbers of successfully cryopreserved embryos. This sensitivity to warming rite is typical of devitrification. The variability in survival is reduced using embryos of a precisely determined embryonic stage. The vitrification of the older, fifteen-hour, embryos yields an optimized hatching rate of 68%, with 35 - 40% of the resulting larvae developing to normal adults. This Success rite in embryos of this age may reflect a reduced sensitivity to limited devitrification or a more even distribution of the ethylene glycol within the embryo.« less

Evaluating the zebrafish embryo toxicity test for pesticide hazard screening.

PubMed

Glaberman, Scott; Padilla, Stephanie; Barron, Mace G

2017-05-01

Given the numerous chemicals used in society, it is critical to develop tools for accurate and efficient evaluation of potential risks to human and ecological receptors. Fish embryo acute toxicity tests are 1 tool that has been shown to be highly predictive of standard, more resource-intensive, juvenile fish acute toxicity tests. However, there is also evidence that fish embryos are less sensitive than juvenile fish for certain types of chemicals, including neurotoxicants. The utility of fish embryos for pesticide hazard assessment was investigated by comparing published zebrafish embryo toxicity data from pesticides with median lethal concentration 50% (LC50) data for juveniles of 3 commonly tested fish species: rainbow trout, bluegill sunfish, and sheepshead minnow. A poor, albeit significant, relationship (r 2  = 0.28; p < 0.05) was found between zebrafish embryo and juvenile fish toxicity when pesticides were considered as a single group, but a much better relationship (r 2  = 0.64; p < 0.05) when pesticide mode of action was factored into an analysis of covariance. This discrepancy is partly explained by the large number of neurotoxic pesticides in the dataset, supporting previous findings that commonly used fish embryo toxicity test endpoints are particularly insensitive to neurotoxicants. These results indicate that it is still premature to replace juvenile fish toxicity tests with embryo-based tests such as the Organisation for Economic Co-operation and Development Fish Embryo Acute Toxicity Test for routine pesticide hazard assessment, although embryo testing could be used with other screening tools for testing prioritization. Environ Toxicol Chem 2017;36:1221-1226. © 2016 SETAC. © 2016 SETAC.

Novel Harmful Recessive Haplotypes Identified for Fertility Traits in Nordic Holstein Cattle

PubMed Central

Sahana, Goutam; Nielsen, Ulrik Sander; Aamand, Gert Pedersen; Lund, Mogens Sandø; Guldbrandtsen, Bernt

2013-01-01

Using genomic data, lethal recessives may be discovered from haplotypes that are common in the population but never occur in the homozygote state in live animals. This approach only requires genotype data from phenotypically normal (i.e. live) individuals and not from the affected embryos that die. A total of 7,937 Nordic Holstein animals were genotyped with BovineSNP50 BeadChip and haplotypes including 25 consecutive markers were constructed and tested for absence of homozygotes states. We have identified 17 homozygote deficient haplotypes which could be loosely clustered into eight genomic regions harboring possible recessive lethal alleles. Effects of the identified haplotypes were estimated on two fertility traits: non-return rates and calving interval. Out of the eight identified genomic regions, six regions were confirmed as having an effect on fertility. The information can be used to avoid carrier-by-carrier mattings in practical animal breeding. Further, identification of causative genes/polymorphisms responsible for lethal effects will lead to accurate testing of the individuals carrying a lethal allele. PMID:24376603

Rewiring of embryonic glucose metabolism via suppression of PFK-1 and aldolase during mouse chorioallantoic branching

PubMed Central

Sugiura, Yuki; Honda, Kurara; Kondo, Koki; Miura, Masayuki

2017-01-01

Adapting the energy metabolism state to changing bioenergetic demands is essential for mammalian development accompanying massive cell proliferation and cell differentiation. However, it remains unclear how developing embryos meet the changing bioenergetic demands during the chorioallantoic branching (CB) stage, when the maternal-fetal exchange of gases and nutrients is promoted. In this study, using metabolome analysis with mass-labeled glucose, we found that developing embryos redirected glucose carbon flow into the pentose phosphate pathway via suppression of the key glycolytic enzymes PFK-1 and aldolase during CB. Concomitantly, embryos exhibited an increase in lactate pool size and in the fractional contribution of glycolysis to lactate biosynthesis. Imaging mass spectrometry visualized lactate-rich tissues, such as the dorsal or posterior neural tube, somites and head mesenchyme. Furthermore, we found that the heterochronic gene Lin28a could act as a regulator of the metabolic changes observed during CB. Perturbation of glucose metabolism rewiring by suppressing Lin28a downregulation resulted in perinatal lethality. Thus, our work demonstrates that developing embryos rewire glucose metabolism following CB for normal development. PMID:28049690

Evidence against a direct role for oxidative stress in cadmium-induced axial malformation in the chick embryo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thompson, Jennifer, E-mail: jennifer.thompson@ucd.i; Doi, Takashi; The Children's Research Centre, Our Lady's Children's Hospital, Dublin 12

Cadmium (Cd) is a powerful inducer of oxidative stress. It also causes ventral body wall defects in chick embryos treated at Hamburger-Hamilton stages 16-17. By measuring malondialdehyde levels (TBARS method) and cotreating with antioxidants (tempol, ascorbate, and N-acetylcysteine), we sought to determine if oxidative stress were directly related to teratogenesis. We also investigated the expression of mRNAs for antioxidant enzymes superoxide dismutase (SOD) -1 and -2, catalase (CAT), and glutathione peroxidase (GPx). RT-PCR showed reductions in SOD-1, SOD-2, and CAT 1 hour after treatment with Cd. MDA levels increased 4 hours after Cd, and remained elevated 24 hours after treatment.more » Of the antioxidants, only N-acetylcysteine reduced MDA levels to control values. Nonetheless, no antioxidant could reduce embryo lethality or malformation rates. Furthermore, MDA levels 24 hours after treatment were identical in malformed and normal embryos exposed to Cd. Hence, we conclude that oxidative stress may not have a direct role in Cd teratogenesis.« less

Impaired expression of importin/karyopherin {beta}1 leads to post-implantation lethality

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miura, Katsutaka; Yoshinobu, Kumiko; Imaizumi, Takashi

2006-03-03

Importin {beta}1 (Imp{beta})/karyopherin {beta}1 (Kpnb1) mediates the nuclear import of a large variety of substrates. This study aimed to investigate the requirement for the Kpnb1 gene in mouse development, using a gene trap line, B6-CB-Ayu8108 {sup GtgeoIMEG} (Ayu8108 {sup geo}), in which the trap vector was inserted into the promoter region of the Kpnb1 gene, but in reverse orientation of the Kpnb1 gene. Ayu8108 {sup geo/geo} homozygous embryos could develop to the blastocyst stage, but died before embryonic day 5.5, and expression of the Kpnb1 gene in homozygous blastocysts was undetectable. We also replaced the {beta}geo gene with Imp{beta} cDNAmore » through Cre-mediated recombination to rescue Imp{beta} expression. Homozygous mice for the rescued allele Ayu8108 {sup Imp{beta}}{sup /Imp{beta}} were born and developed normally. These results demonstrated that the cause of post-implantation lethality of Ayu8108 {sup geo/geo} homozygous embryos was impaired expression of the Kpnb1 gene, indicating indispensable roles of Imp{beta}1 in early development of mice.« less

The story of DNase II: a stifled death-wish leads to self-harm.

PubMed

Crow, Yanick J

2010-09-01

DNase II is an endonuclease which plays a fundamental role in the degradation of DNA from both apoptotic cells, and nuclei extruded from red blood cells during erythropoiesis: important tasks, considering that everyday 10(8)-10(9) cells undergo apoptosis, and 10(11) red blood cells are produced in the adult human. The DNase II-null mouse demonstrates embryonic lethality due to type I interferon-mediated erythroid precursor cell death triggered by undegraded nucleic acids. However, the mechanisms leading to such cytotoxicity are poorly understood. A study in the current issue of the European Journal of Immunology investigates the role of the death ligand TRAIL in this process. Although TRAIL is shown to be dispensable for the interferon-induced apoptosis of erythroid cells in DNAse II(-/-) embryos, the authors have developed a useful strategy for further exploring this question in future studies. Interestingly, earlier studies by the same group showed that crossing the DNase II-null mouse with a mouse deficient for the type I interferon receptor can rescue the lethal anaemia observed in the DNase II-null embryos, but only at the cost of developing autoimmunity.

Flt1/VEGFR1 heterozygosity causes transient embryonic edema.

PubMed

Otowa, Yasunori; Moriwaki, Kazumasa; Sano, Keigo; Shirakabe, Masanori; Yonemura, Shigenobu; Shibuya, Masabumi; Rossant, Janet; Suda, Toshio; Kakeji, Yoshihiro; Hirashima, Masanori

2016-06-02

Vascular endothelial growth factor-A is a major player in vascular development and a potent vascular permeability factor under physiological and pathological conditions by binding to a decoy receptor Flt1 and its primary receptor Flk1. In this study, we show that Flt1 heterozygous (Flt1(+/-)) mouse embryos grow up to adult without life-threatening abnormalities but exhibit a transient embryonic edema around the nuchal and back regions, which is reminiscent of increased nuchal translucency in human fetuses. Vascular permeability is enhanced and an intricate infolding of the plasma membrane and huge vesicle-like structures are seen in Flt1(+/-) capillary endothelial cells. Flk1 tyrosine phosphorylation is elevated in Flt1(+/-) embryos, but Flk1 heterozygosity does not suppress embryonic edema caused by Flt1 heterozygosity. When Flt1 mutants are crossed with Aspp1(-/-) mice which exhibit a transient embryonic edema with delayed formation and dysfunction of lymphatic vessels, only 5.7% of Flt1(+/-); Aspp1(-/-) mice survive, compared to expected ratio (25%). Our results demonstrate that Flt1 heterozygosity causes a transient embryonic edema and can be a risk factor for embryonic lethality in combination with other mutations causing non-lethal vascular phenotype.

TORC2 signaling antagonizes SKN-1 to induce C. elegans mesendodermal embryonic development

PubMed Central

Ruf, Vanessa; Holzem, Christina; Peyman, Tobias; Walz, Gerd; Blackwell, T. Keith; Neumann-Haefelin, Elke

2013-01-01

The evolutionarily conserved target of rapamycin (TOR) kinase controls fundamental metabolic processes to support cell and tissue growth. TOR functions within the context of two distinct complexes, TORC1 and TORC2. TORC2, with its specific component Rictor, has been recently implicated in aging and regulation of growth and metabolism. Here, we identify rict-1/Rictor as a regulator of embryonic development in C. elegans. The transcription factor skn-1 establishes development of the mesendoderm in embryos, and is required for cellular homeostasis and longevity in adults. Loss of maternal skn-1 function leads to misspecification of the mesendodermal precursor and failure to form intestine and pharynx. We found that genetic inactivation of rict-1 suppressed skn-1-associated lethality by restoring mesendodermal specification in skn-1 deficient embryos. Inactivation of other TORC2 but not TORC1 components also partially rescued skn-1 embryonic lethality. The SGK-1 kinase mediated these functions downstream of rict-1/TORC2, as a sgk-1 gain-of-function mutant suppressed the rict-1 mutant phenotype. These data indicate that TORC2 and SGK-1 antagonize SKN-1 during embryonic development. PMID:23973804

Two redundant octanoyltransferases and one obligatory lipoyl synthase provide protein-lipoylation autonomy to plastids of Arabidopsis.

PubMed

Ewald, R; Hoffmann, C; Neuhaus, E; Bauwe, H

2014-01-01

Octanoyltransferases (LIP2) are important for the lipoylation of several α-ketoacid decarboxylases and glycine decarboxylase, all of which are essential multienzyme complexes of central metabolism, by attaching de novo-synthesised octanoyl moieties to the respective target subunits. Lipoyl synthase (LIP1) then inserts two sulphur atoms each into the protein-bound octanoyl chains to generate the functional lipoamide arms. In plants, most of the above multienzyme complexes occur only in mitochondria. Pyruvate dehydrogenase is an exception, since it also occurs in plastids. Plastidial LIP1 and LIP2 are known, but it is not clear how essential these enzymes are. Here, we report that not just one but two redundant LIP2 isoforms, LIP2p and LIP2p2, operate in plastids of Arabidopsis. The combined deletion of the two isoenzymes is embryo-lethal. Deletion of the plastidial lipoyl synthase LIP1p is also embryo-lethal, indicating that all plastidial LIP1 activity is due to LIP1p. These features suggest that protein lipoylation is based on an autonomous and partially redundant de novo lipoylation pathway in plastids. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

Occurrence of Harmful Cyanobacteria in Drinking Water from a Severely Drought-Impacted Semi-arid Region

PubMed Central

Walter, Juline M.; Lopes, Fabyano A. C.; Lopes-Ferreira, Mônica; Vidal, Lívia M.; Leomil, Luciana; Melo, Fabiana; de Azevedo, Girlene S.; Oliveira, Rossandra M. S.; Medeiros, Alba J.; Melo, Adriana S. O.; De Rezende, Carlos E.; Tanuri, Amilcar; Thompson, Fabiano L.

2018-01-01

Harmful cyanobacterial blooms have become increasingly common in freshwater ecosystems in recent decades, mainly due to eutrophication and climate change. Water becomes unreliable for human consumption. Here, we report a comprehensive study carried out to investigate the water quality of several Campina Grande reservoirs. Our approach included metagenomics, microbial abundance quantification, ELISA test for three cyanotoxins (microcystin, nodularins, and cylindrospermopsin), and in vivo ecotoxicological tests with zebrafish embryos. Cytometry analysis showed high cyanobacterial abundance, while metagenomics identified an average of 10.6% of cyanobacterial sequences, and demonstrated the presence of Microcystis, Cylindrospermopsis, and toxin coding genes in all ponds. Zebrafish embryos reared with pond water had high mortality and diverse malformations. Among the ponds analyzed, Araçagi showed the highest lethality (an average of 62.9 ± 0.8%), followed by Boqueirão (lethality average of 62.5 ± 0.8%). Here, we demonstrate that water from ponds undergoing extremely drought conditions have an abundance of potentially harmful cyanobacteria and their toxins. Our findings are consistent with a scenario in which polluted drinking water poses a great risk to human health. PMID:29541063

Effects of a commonly used glyphosate-based herbicide formulation on early developmental stages of two anuran species.

PubMed

Wagner, Norman; Müller, Hendrik; Viertel, Bruno

2017-01-01

Environmental contamination, especially due to the increasing use of pesticides, is suggested to be one out of six main reasons for the global amphibian decline. Adverse effects of glyphosate-based herbicides on amphibians have been already discussed in several studies with different conclusions, especially regarding sublethal effects at environmentally relevant concentrations. Therefore, we studied the acute toxic effects (mortality, growth, and morphological changes) of the commonly used glyphosate-based herbicide formulation Roundup® UltraMax on early aquatic developmental stages of two anuran species with different larval types (obligate vs. facultative filtrating suspension feeders), the African clawed frog (Xenopus laevis) and the Mediterranean painted frog (Discoglossus pictus). While X. laevis is an established anuran model organism in amphibian toxicological studies, we aim to establish D. pictus as another model for species with facultative filtrating larvae. A special focus of the present study lies on malformations in X. laevis embryos, which were investigated using histological preparations. In general, embryos and larvae of X. laevis reacted more sensitive concerning lethal effects compared to early developmental stages of D. pictus. It was suggested, that especially the different morphology of their filter apparatus and the higher volume of water pumped through the buccopharynx of X. laevis larvae lead to higher exposure to the formulation. The test substance induced similar lethal effects in D. pictus larvae as it does in the teleost standard test organism used in pesticide approval, the rainbow trout (Oncorhynchus mykiss), whereas embryos of both species are apparently more tolerant and, conversely, X. laevis larvae about two times more sensitive. In both species, early larvae always reacted significantly more sensitive than embryos. Exposure to the test substance increased malformation rates in embryos of both species in a concentration-dependent manner, but not at environmentally relevant concentrations. However, the assumed field safety, based on calculated surface water concentrations of the active ingredient (glyphosate), should be validated with realistic field data and buffer strips have to be urgently regarded to any aquatic amphibian habitat.

Gene expression analysis in zebrafish embryos: a potential approach to predict effect concentrations in the fish early life stage test.

PubMed

Weil, Mirco; Scholz, Stefan; Zimmer, Michaela; Sacher, Frank; Duis, Karen

2009-09-01

Based on the hypothesis that analysis of gene expression could be used to predict chronic fish toxicity, the zebrafish (Danio rerio) embryo test (DarT), developed as a replacement method for the acute fish test, was expanded to a gene expression D. rerio embryo test (Gene-DarT). The effects of 14 substances on lethal and sublethal endpoints of the DarT and on expression of potential marker genes were investigated: the aryl hydrocarbon receptor 2, cytochrome P450 1A (cypla), heat shock protein 70, fizzy-related protein 1, the transcription factors v-maf musculoaponeurotic fibrosarcoma oncogene family protein g (avian) 1 and NF-E2-p45-related factor, and heme oxygenase 1 (hmox1). After exposure of zebrafish embryos for 48 h, differential gene expression was evaluated using reverse transcriptase-polymerase chain reaction, gel electrophoresis, and densitometric analysis of the gels. All tested compounds significantly affected the expression of at least one potential marker gene, with cyp1a and hmox1 being most sensitive. Lowest-observed-effect concentrations (LOECs) for gene expression were below concentrations resulting in 10% lethal effects in the DarT. For 10 (3,4- and 3,5-dichloroaniline, 1,4-dichlorobenzene, 2,4-dinitrophenol, atrazine, parathion-ethyl, chlorotoluron, genistein, 4-nitroquinoline-1-oxide, and cadmium) out of the 14 tested substances, LOEC values derived with the Gene-DarT differ by a factor of less than 10 from LOEC values of fish early life stage tests with zebrafish. For pentachloroaniline and pentachlorobenzene, the Gene-DarT showed a 23- and 153-fold higher sensitivity, respectively, while for lindane, it showed a 13-fold lower sensitivity. For ivermectin, the Gene-DarT was by a factor of more than 1,000 less sensitive than the acute fish test. The results of the present study indicate that gene expression analysis in zebrafish embryos could principally be used to predict effect concentrations in the fish early life stage test.

MRG15 Regulates Embryonic Development and Cell Proliferation

PubMed Central

Tominaga, Kaoru; Kirtane, Bhakti; Jackson, James G.; Ikeno, Yuji; Ikeda, Takayoshi; Hawks, Christina; Smith, James R.; Matzuk, Martin M.; Pereira-Smith, Olivia M.

2005-01-01

MRG15 is a highly conserved protein, and orthologs exist in organisms from yeast to humans. MRG15 associates with at least two nucleoprotein complexes that include histone acetyltransferases and/or histone deacetylases, suggesting it is involved in chromatin remodeling. To study the role of MRG15 in vivo, we generated knockout mice and determined that the phenotype is embryonic lethal, with embryos and the few stillborn pups exhibiting developmental delay. Immunohistochemical analysis indicates that apoptosis in Mrg15−/− embryos is not increased compared with wild-type littermates. However, the number of proliferating cells is significantly reduced in various tissues of the smaller null embryos compared with control littermates. Cell proliferation defects are also observed in Mrg15−/− mouse embryonic fibroblasts. The hearts of the Mrg15−/− embryos exhibit some features of hypertrophic cardiomyopathy. The increase in size of the cardiomyocytes is most likely a response to decreased growth of the cells. Mrg15−/− embryos appeared pale, and microarray analysis revealed that α-globin gene expression was decreased in null versus wild-type embryos. We determined by chromatin immunoprecipitation that MRG15 was recruited to the α-globin promoter during dimethyl sulfoxide-induced mouse erythroleukemia cell differentiation. These findings demonstrate that MRG15 has an essential role in embryonic development via chromatin remodeling and transcriptional regulation. PMID:15798182

Zebrafish (Danio rerio) embryos as a model for testing proteratogens.

PubMed

Weigt, Stefan; Huebler, Nicole; Strecker, Ruben; Braunbeck, Thomas; Broschard, Thomas H

2011-03-15

Zebrafish embryos have been shown to be a useful model for the detection of direct acting teratogens. This communication presents a protocol for a 3-day in vitro zebrafish embryo teratogenicity assay and describes results obtained for 10 proteratogens: 2-acetylaminofluorene, benzo[a]pyrene, aflatoxin B(1), carbamazepine, phenytoin, trimethadione, cyclophosphamide, ifosfamide, tegafur and thio-TEPA. The selection of the test substances accounts for differences in structure, origin, metabolism and water solubility. Apart from 2-acetylaminofluorene, which mainly produces lethal effects, all proteratogens tested were teratogenic in zebrafish embryos exposed for 3 days. The test substances and/or the substance class produced characteristic patterns of fingerprint endpoints. Several substances produced effects that could be identified already at 1 dpf (days post fertilization), whereas the effects of others could only be identified unambiguously after hatching at ≥ 3 dpf. The LC₅₀ and EC₅₀ values were used to calculate the teratogenicity index (TI) for the different substances, and the EC₂₀ values were related to human plasma concentrations. Results lead to the conclusion that zebrafish embryos are able to activate proteratogenic substances without addition of an exogenous metabolic activation system. Moreover, the teratogenic effects were observed at concentrations relevant to human exposure data. Along with other findings, our results indicate that zebrafish embryos are a useful alternative method for traditional teratogenicity testing with mammalian species. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

LGR4 and LGR5 are R-spondin receptors mediating Wnt/β-catenin and Wnt/PCP signalling.

PubMed

Glinka, Andrei; Dolde, Christine; Kirsch, Nadine; Huang, Ya-Lin; Kazanskaya, Olga; Ingelfinger, Dierk; Boutros, Michael; Cruciat, Cristina-Maria; Niehrs, Christof

2011-09-30

R-spondins are secreted Wnt signalling agonists, which regulate embryonic patterning and stem cell proliferation, but whose mechanism of action is poorly understood. Here we show that R-spondins bind to the orphan G-protein-coupled receptors LGR4 and LGR5 by their Furin domains. Gain- and loss-of-function experiments in mammalian cells and Xenopus embryos indicate that LGR4 and LGR5 promote R-spondin-mediated Wnt/β-catenin and Wnt/PCP signalling. R-spondin-triggered β-catenin signalling requires Clathrin, while Wnt3a-mediated β-catenin signalling requires Caveolin-mediated endocytosis, suggesting that internalization has a mechanistic role in R-spondin signalling.

LGR4 and LGR5 are R-spondin receptors mediating Wnt/β-catenin and Wnt/PCP signalling

PubMed Central

Glinka, Andrei; Dolde, Christine; Kirsch, Nadine; Huang, Ya-Lin; Kazanskaya, Olga; Ingelfinger, Dierk; Boutros, Michael; Cruciat, Cristina-Maria; Niehrs, Christof

2011-01-01

R-spondins are secreted Wnt signalling agonists, which regulate embryonic patterning and stem cell proliferation, but whose mechanism of action is poorly understood. Here we show that R-spondins bind to the orphan G-protein-coupled receptors LGR4 and LGR5 by their Furin domains. Gain- and loss-of-function experiments in mammalian cells and Xenopus embryos indicate that LGR4 and LGR5 promote R-spondin-mediated Wnt/β-catenin and Wnt/PCP signalling. R-spondin-triggered β-catenin signalling requires Clathrin, while Wnt3a-mediated β-catenin signalling requires Caveolin-mediated endocytosis, suggesting that internalization has a mechanistic role in R-spondin signalling. PMID:21909076

The evolving role of the orphan nuclear receptor ftz-f1, a pair-rule segmentation gene.

PubMed

Heffer, Alison; Grubbs, Nathaniel; Mahaffey, James; Pick, Leslie

2013-01-01

Segmentation is a critical developmental process that occurs by different mechanisms in diverse taxa. In insects, there are three common modes of embryogenesis-short-, intermediate-, and long-germ development-which differ in the number of segments specified at the blastoderm stage. While genes involved in segmentation have been extensively studied in the long-germ insect Drosophila melanogaster (Dm), it has been found that their expression and function in segmentation in short- and intermediate-germ insects often differ. Drosophila ftz-f1 encodes an orphan nuclear receptor that functions as a maternally expressed pair-rule segmentation gene, responsible for the formation of alternate body segments during Drosophila embryogenesis. Here we investigated the expression and function of ftz-f1 in the short-germ beetle, Tribolium castaneum (Tc). We found that Tc-ftz-f1 is expressed in stripes in Tribolium embryos. These stripes overlap alternate Tc-Engrailed (Tc-En) stripes, indicative of a pair-rule expression pattern. To test whether Tc-ftz-f1 has pair-rule function, we utilized embryonic RNAi, injecting double-stranded RNA corresponding to Tc-ftz-f1 coding or non-coding regions into early Tribolium embryos. Knockdown of Tc-ftz-f1 produced pair-rule segmentation defects, evidenced by loss of expression of alternate En stripes. In addition, a later role for Tc-ftz-f1 in cuticle formation was revealed. These results identify a new pair-rule gene in Tribolium and suggest that its role in segmentation may be shared among holometabolous insects. Interestingly, while Tc-ftz-f1 is expressed in pair-rule stripes, the gene is ubiquitously expressed in Drosophila embryos. Thus, the pair-rule function of ftz-f1 is conserved despite differences in expression patterns of ftz-f1 genes in different lineages. This suggests that ftz-f1 expression changed after the divergence of lineages leading to extant beetles and flies, likely due to differences in cis-regulatory sequences. We propose that the dependence of Dm-Ftz-F1 on interaction with the homeodomain protein Ftz which is expressed in stripes in Drosophila, loosened constraints on Dm-ftz-f1 expression, allowing for ubiquitous expression of this pair-rule gene in Drosophila. © 2013 Wiley Periodicals, Inc.

Effect of coniine on the developing chick embryo.

PubMed

Forsyth, C S; Frank, A A; Watrous, B J; Bohn, A A

1994-04-01

Coniine, an alkaloid from Conium maculatum (poison hemlock), has been shown to be teratogenic in livestock. The major teratogenic outcome is arthrogryposis, presumably due to nicotinic receptor blockade. However, coniine has failed to produce arthrogryposis in rats or mice and is only weakly teratogenic in rabbits. The purpose of this study was to evaluate and compare the effects of coniine and nicotine in the developing chick. Concentrations of coniine and nicotine sulfate were 0.015%, 0.03%, 0.075%, 0.15%, 0.75%, 1.5%, 3%, and 6% and 1%, 5%, and 10%, respectively. Both compounds caused deformations and lethality in a dose-dependent manner. All concentrations of nicotine sulfate caused some lethality but a no effect level for coniine lethality was 0.75%. The deformations caused by both coniine and nicotine sulfate were excessive flexion or extension of one or more toes. No histopathological alterations or differences in bone formation were seen in the limbs or toes of any chicks from any group; however, extensive cranial hemorrhage occurred in all nicotine sulfate-treated chicks. There was a statistically significant (P < or = 0.01) decrease in movement in coniine and nicotine sulfate treated chicks as determined by ultrasound. Control chicks were in motion an average of 33.67% of the time, while coniine-treated chicks were only moving 8.95% of a 5-min interval, and no movement was observed for nicotine sulfate treated chicks. In summary, the chick embryo provides a reliable and simple experimental animal model of coniine-induced arthrogryposis. Data from this model support a mechanism involving nicotinic receptor blockade with subsequent decreased fetal movement.

Jmjd5 functions as a regulator of p53 signaling during mouse embryogenesis.

PubMed

Ishimura, Akihiko; Terashima, Minoru; Tange, Shoichiro; Suzuki, Takeshi

2016-03-01

Genetic studies have shown that aberrant activation of p53 signaling leads to embryonic lethality. Maintenance of a fine balance of the p53 protein level is critical for normal development. Previously, we have reported that Jmjd5, a member of the Jumonji C (JmjC) family, regulates embryonic cell proliferation through the control of Cdkn1a expression. Since Cdkn1a is the representative p53-regulated gene, we have examined whether the expression of other p53 target genes is coincidentally upregulated with Cdkn1a in Jmjd5-deficient embryos. The expression of a subset of p53-regulated genes was increased in both Jmjd5 hypomorphic mouse embryonic fibroblasts (MEFs) and Jmjd5-deficient embryos at embryonic day 8.25 without the induced expression of Trp53. Intercrossing of Jmjd5-deficient mice with Trp53 knockout mice showed that the growth defect of Jmjd5 mutant cells was significantly recovered under a Trp53 null genetic background. Chromatin immunoprecipitation analysis in Jmjd5 hypomorphic MEFs indicated the increased recruitment of p53 at several p53 target gene loci, such as Cdkn1a, Pmaip1, and Mdm2. These results suggest that Jmjd5 is involved in the transcriptional regulation of a subset of p53-regulated genes, possibly through the control of p53 recruitment at the gene loci. In Jmjd5-deficient embryos, the enhanced recruitment of p53 might result in the abnormal activation of p53 signaling leading to embryonic lethality.

Oxidative stress, endocrine disruption, and malformation of Bufo gargarizans embryo exposed to sub-lethal cadmium concentrations.

PubMed

Wu, Chao; Zhang, Yuhui; Chai, Lihong; Wang, Hongyuan

2017-01-01

Thyroid hormone (TH) is critical for vertebrate postembryonic development as well as embryonic development. Chinese toad (Bufo gargarizans) embryos were exposed to different concentrations of cadmium (5, 50, 100, 200 and 500μg Cd L -1 ) for 7days. Malformations were monitored daily, and growth and development of embryos were measured at day 4 and 7, and type 2 and 3 iodothyronine deiodinase (Dio2 and Dio3), thyroid hormone receptors (TRα and TRβ) mRNA levels were also measured to assess disruption of TH synthesis. In addition, superoxide dismutase (SOD), glutathione peroxidase (GPx) and heat shock proteins (HSPs) mRNA expression were examined to evaluate the ability of scavenging ROS. Our results demonstrated a bimodal inhibitory effect of Cd on the embryo growth and development of Bufo gargarizans. Reduced mean stage, total length and weight were observed at 5, 50, 200 and 500, but not at 100μg Cd L -1 . Embryos malformation occurred in all cadmium treatments. Morphological abnormalities of embryos are characterized by axial flexures, abdominal edema, stunted growth and fin flexure. Real-time PCR results show that exposure to cadmium down-regulated TRα and Dio3 mRNA expression and up-regulated Dio2 mRNA level. SOD and GPx mRNA expression was significantly up-regulated after cadmium exposure. We concluded that cadmium could change mRNA expression of TRα, Dio2 and Dio3 leading the inhibition of growth and development of B. gargarizans embryo, which suggests that cadmium might have the endocrine-disrupting effect in embryos. Moreover, the reduced ability of scavenging ROS induced by cadmium might be responsible for the teratogenic effects of cadmium. Copyright © 2016 Elsevier B.V. All rights reserved.

Potent Phototoxicity of Marine Bunker Oil to Translucent Herring Embryos after Prolonged Weathering

PubMed Central

Incardona, John P.; Vines, Carol A.; Linbo, Tiffany L.; Myers, Mark S.; Sloan, Catherine A.; Anulacion, Bernadita F.; Boyd, Daryle; Collier, Tracy K.; Morgan, Steven; Cherr, Gary N.; Scholz, Nathaniel L.

2012-01-01

Pacific herring embryos (Clupea pallasi) spawned three months following the Cosco Busan bunker oil spill in San Francisco Bay showed high rates of late embryonic mortality in the intertidal zone at oiled sites. Dead embryos developed to the hatching stage (e.g. fully pigmented eyes) before suffering extensive tissue deterioration. In contrast, embryos incubated subtidally at oiled sites showed evidence of sublethal oil exposure (petroleum-induced cardiac toxicity) with very low rates of mortality. These field findings suggested an enhancement of oil toxicity through an interaction between oil and another environmental stressor in the intertidal zone, such as higher levels of sunlight-derived ultraviolet (UV) radiation. We tested this hypothesis by exposing herring embryos to both trace levels of weathered Cosco Busan bunker oil and sunlight, with and without protection from UV radiation. Cosco Busan oil and UV co-exposure were both necessary and sufficient to induce an acutely lethal necrotic syndrome in hatching stage embryos that closely mimicked the condition of dead embryos sampled from oiled sites. Tissue levels of known phototoxic polycyclic aromatic compounds were too low to explain the observed degree of phototoxicity, indicating the presence of other unidentified or unmeasured phototoxic compounds derived from bunker oil. These findings provide a parsimonious explanation for the unexpectedly high losses of intertidal herring spawn following the Cosco Busan spill. The chemical composition and associated toxicity of bunker oils should be more thoroughly evaluated to better understand and anticipate the ecological impacts of vessel-derived spills associated with an expanding global transportation network. PMID:22312421

SOCS3: an essential regulator of LIF receptor signaling in trophoblast giant cell differentiation

PubMed Central

Takahashi, Yutaka; Carpino, Nick; Cross, James C.; Torres, Miguel; Parganas, Evan; Ihle, James N.

2003-01-01

Suppressor of cytokine signaling 3 (SOCS3) binds cytokine receptors and thereby suppresses cytokine signaling. Deletion of SOCS3 causes an embryonic lethality that is rescued by a tetraploid rescue approach, demonstrating an essential role in placental development and a non-essential role in embryo development. Rescued SOCS3-deficient mice show a perinatal lethality with cardiac hypertrophy. SOCS3-deficient placentas have reduced spongiotrophoblasts and increased trophoblast secondary giant cells. Enforced expression of SOCS3 in a trophoblast stem cell line (Rcho-1) suppresses giant cell differentiation. Conversely, SOCS3-deficient trophoblast stem cells differentiate more readily to giant cells in culture, demonstrating that SOCS3 negatively regulates trophoblast giant cell differentiation. Leukemia inhibitory factor (LIF) promotes giant cell differentiation in vitro, and LIF receptor (LIFR) deficiency results in loss of giant cell differentiation in vivo. Finally, LIFR deficiency rescues the SOCS3-deficient placental defect and embryonic lethality. The results establish SOCS3 as an essential regulator of LIFR signaling in trophoblast differentiation. PMID:12554639

RIPK3 Mediates Necroptosis during Embryonic Development and Postnatal Inflammation in Fadd-Deficient Mice.

PubMed

Zhao, Qun; Yu, XianJun; Zhang, HaiWei; Liu, YongBo; Zhang, XiXi; Wu, XiaoXia; Xie, Qun; Li, Ming; Ying, Hao; Zhang, Haibing

2017-04-25

RIPK3 mediates cell death and regulates inflammatory responses. Although genetic studies have suggested that RIPK3-MLKL-mediated necroptosis leads to embryonic lethality in Fadd or Caspase-8-deficient mice, the exact mechanisms are not fully understood. Here, we generated Ripk3 mutant mice by altering the RIPK3 kinase domain (Ripk3 Δ/Δ mice), thus abolishing its kinase activity. Ripk3 Δ/Δ cells were resistant to necroptosis stimulation in vitro, and Ripk3 Δ/Δ mice were protected from necroptotic diseases. Although the Ripk3 Δ/Δ mutation rescued embryonic lethality in Fadd -/- embryos, Fadd -/- Ripk3 Δ/Δ mice died within 1 day after birth due to massive inflammation. These results indicate that Ripk3 ablation rescues embryonic lethality in Fadd-deficient mice by suppressing two RIPK3-mediating processes: necroptosis during embryogenesis and inflammation during postnatal development in Fadd -/- mice. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Effects of the insecticide permethrin on three life stages of the grass shrimp, Palaemonetes pugio.

PubMed

DeLorenzo, M E; Serrano, L; Chung, K W; Hoguet, J; Key, P B

2006-06-01

Toxicity of the pyrethroid insecticide permethrin was assessed using three life stages of the estuarine grass shrimp, Palaemonetes pugio. Adult and larval shrimp were tested with and without sediment. An aqueous embryo test was also conducted. Cellular stress biomarkers, glutathione, and lipid peroxidation, were assessed. Larval shrimp were the most sensitive life stage with a 96-h lethal concentration (LC(50)) value of 0.05 microg/L, compared to 0.25 microg/L for adults, and 6.4 microg/L for embryos. The presence of sediment significantly decreased toxicity of permethrin to both adult and larval shrimp. Permethrin exposure increased time to hatch in embryos and decreased swimming behavior of larvae. Lipid peroxidation levels were significantly decreased in the adult shrimp, but increased in larval shrimp exposed to permethrin. Low levels of permethrin may negatively affect grass shrimp health and survival. Permethrin use in the coastal zone should be carefully managed to avoid adverse impacts on nontarget estuarine organisms.

Inter-laboratory assessment of a harmonized zebrafish developmental toxicology assay - progress report on phase I.

PubMed

Gustafson, A-L; Stedman, D B; Ball, J; Hillegass, J M; Flood, A; Zhang, C X; Panzica-Kelly, J; Cao, J; Coburn, A; Enright, B P; Tornesi, M B; Hetheridge, M; Augustine-Rauch, K A

2012-04-01

This report provides a progress update of a consortium effort to develop a harmonized zebrafish developmental toxicity assay. Twenty non-proprietary compounds (10 animal teratogens and 10 animal non-teratogens) were evaluated blinded in 4 laboratories. Zebrafish embryos from pond-derived and cultivated strain wild types were exposed to the test compounds for 5 days and subsequently evaluated for lethality and morphological changes. Each of the testing laboratories achieved similar overall concordance to the animal data (60-70%). Subsequent optimization procedures to improve the overall concordance focused on compound formulation and test concentration adjustments, chorion permeation and number of replicates. These optimized procedures were integrated into a revised protocol and all compounds were retested in one lab using embryos from pond-derived zebrafish and achieved 85% total concordance. To further assess assay performance, a study of additional compounds is currently in progress at two laboratories using embryos from pond-derived and cultivated-strain wild type zebrafish. Copyright © 2011 Elsevier Inc. All rights reserved.

Live dynamic imaging and analysis of developmental cardiac defects in mouse models with optical coherence tomography

NASA Astrophysics Data System (ADS)

Lopez, Andrew L.; Wang, Shang; Garcia, Monica; Valladolid, Christian; Larin, Kirill V.; Larina, Irina V.

2015-03-01

Understanding mouse embryonic development is an invaluable resource for our interpretation of normal human embryology and congenital defects. Our research focuses on developing methods for live imaging and dynamic characterization of early embryonic development in mouse models of human diseases. Using multidisciplinary methods: optical coherence tomography (OCT), live mouse embryo manipulations and static embryo culture, molecular biology, advanced image processing and computational modeling we aim to understand developmental processes. We have developed an OCT based approach to image live early mouse embryos (E8.5 - E9.5) cultured on an imaging stage and visualize developmental events with a spatial resolution of a few micrometers (less than the size of an individual cell) and a frame rate of up to hundreds of frames per second and reconstruct cardiodynamics in 4D (3D+time). We are now using these methods to study how specific embryonic lethal mutations affect cardiac morphology and function during early development.

Toxic effects of brominated indoles and phenols on zebrafish embryos.

PubMed

Kammann, U; Vobach, M; Wosniok, W

2006-07-01

Organobromine compounds in the marine environment have been the focus of growing attention in past years. In contrast to anthropogenic brominated flame retardants, other brominated compounds are produced naturally, e.g., by common polychaete worms and algae. Brominated phenols and indoles assumed to be of biogenic origin have been detected in water and sediment extracts from the German Bight. These substances as well as some of their isomers have been tested with the zebrafish embryo test and were found to cause lethal as well as nonlethal malformations. The zebrafish test was able to detect a log K(OW)-related toxicity for bromophenols, suggesting nonpolar narcosis as a major mode of action. Different effect patterns could be observed for brominated indoles and bromophenols. The comparison of effective concentrations in the zebrafish embryo test with the concentrations determined in water samples suggests the possibility that brominated indoles may affect early life stages of marine fish species in the North Sea.

PAK4 kinase is essential for embryonic viability and for proper neuronal development.

PubMed

Qu, Jian; Li, Xiaofan; Novitch, Bennet G; Zheng, Ye; Kohn, Matthew; Xie, Jian-Ming; Kozinn, Spencer; Bronson, Roderick; Beg, Amer A; Minden, Audrey

2003-10-01

The serine/threonine kinase PAK4 is a target for the Rho GTPase Cdc42 and has been shown to regulate cell morphology and cytoskeletal organization in mammalian cells. To examine the physiological and developmental functions of PAK4, we have disrupted the PAK4 gene in mice. The absence of PAK4 led to lethality by embryonic day 11.5, a result most likely due to a defect in the fetal heart. Striking abnormalities were also evident in the nervous systems of PAK4-deficient embryos. These embryos had dramatic defects in neuronal development and axonal outgrowth. In particular, spinal cord motor neurons and interneurons failed to differentiate and migrate to their proper positions. This is probably related to the role for PAK4 in the regulation of cytoskeletal organization and cell and/or extracellular matrix adhesion. PAK4-null embryos also had defects in proper folding of the caudal portion of the neural tube, suggesting an important role for PAK4 in neural tube development.

The Modern Primitives: Applying New Technological Approaches to Explore the Biology of the Earliest Red Blood Cells

PubMed Central

Fraser, Stuart T.

2013-01-01

One of the most critical stages in mammalian embryogenesis is the independent production of the embryo's own circulating, functional red blood cells. Correspondingly, erythrocytes are the first cell type to become functionally mature during embryogenesis. Failure to achieve this invariably leads to in utero lethality. The recent application of technologies such as transcriptome analysis, flow cytometry, mutant embryo analysis, and transgenic fluorescent gene expression reporter systems has shed new light on the distinct erythroid lineages that arise early in development. Here, I will describe the similarities and differences between the distinct erythroid populations that must form for the embryo to survive. While much of the focus of this review will be the poorly understood primitive erythroid lineage, a discussion of other erythroid and hematopoietic lineages, as well as the cell types making up the different niches that give rise to these lineages, is essential for presenting an appropriate developmental context of these cells. PMID:24222861

Rewiring of embryonic glucose metabolism via suppression of PFK-1 and aldolase during mouse chorioallantoic branching.

PubMed

Miyazawa, Hidenobu; Yamaguchi, Yoshifumi; Sugiura, Yuki; Honda, Kurara; Kondo, Koki; Matsuda, Fumio; Yamamoto, Takehiro; Suematsu, Makoto; Miura, Masayuki

2017-01-01

Adapting the energy metabolism state to changing bioenergetic demands is essential for mammalian development accompanying massive cell proliferation and cell differentiation. However, it remains unclear how developing embryos meet the changing bioenergetic demands during the chorioallantoic branching (CB) stage, when the maternal-fetal exchange of gases and nutrients is promoted. In this study, using metabolome analysis with mass-labeled glucose, we found that developing embryos redirected glucose carbon flow into the pentose phosphate pathway via suppression of the key glycolytic enzymes PFK-1 and aldolase during CB. Concomitantly, embryos exhibited an increase in lactate pool size and in the fractional contribution of glycolysis to lactate biosynthesis. Imaging mass spectrometry visualized lactate-rich tissues, such as the dorsal or posterior neural tube, somites and head mesenchyme. Furthermore, we found that the heterochronic gene Lin28a could act as a regulator of the metabolic changes observed during CB. Perturbation of glucose metabolism rewiring by suppressing Lin28a downregulation resulted in perinatal lethality. Thus, our work demonstrates that developing embryos rewire glucose metabolism following CB for normal development. © 2017. Published by The Company of Biologists Ltd.

Impaired mitotic progression and preimplantation lethality in mice lacking OMCG1, a new evolutionarily conserved nuclear protein.

PubMed

Artus, Jérôme; Vandormael-Pournin, Sandrine; Frödin, Morten; Nacerddine, Karim; Babinet, Charles; Cohen-Tannoudji, Michel

2005-07-01

While highly conserved through evolution, the cell cycle has been extensively modified to adapt to new developmental programs. Recently, analyses of mouse mutants revealed that several important cell cycle regulators are either dispensable for development or have a tissue- or cell-type-specific function, indicating that many aspects of cell cycle regulation during mammalian embryo development remain to be elucidated. Here, we report on the characterization of a new gene, Omcg1, which codes for a nuclear zinc finger protein. Embryos lacking Omcg1 die by the end of preimplantation development. In vitro cultured Omcg1-null blastocysts exhibit a dramatic reduction in the total cell number, a high mitotic index, and the presence of abnormal mitotic figures. Importantly, we found that Omcg1 disruption results in the lengthening of M phase rather than in a mitotic block. We show that the mitotic delay in Omcg1-/- embryos is associated with neither a dysfunction of the spindle checkpoint nor abnormal global histone modifications. Taken together, these results suggest that Omcg1 is an important regulator of the cell cycle in the preimplantation embryo.

Impaired Mitotic Progression and Preimplantation Lethality in Mice Lacking OMCG1, a New Evolutionarily Conserved Nuclear Protein†

PubMed Central

Artus, Jérôme; Vandormael-Pournin, Sandrine; Frödin, Morten; Nacerddine, Karim; Babinet, Charles; Cohen-Tannoudji, Michel

2005-01-01

While highly conserved through evolution, the cell cycle has been extensively modified to adapt to new developmental programs. Recently, analyses of mouse mutants revealed that several important cell cycle regulators are either dispensable for development or have a tissue- or cell-type-specific function, indicating that many aspects of cell cycle regulation during mammalian embryo development remain to be elucidated. Here, we report on the characterization of a new gene, Omcg1, which codes for a nuclear zinc finger protein. Embryos lacking Omcg1 die by the end of preimplantation development. In vitro cultured Omcg1-null blastocysts exhibit a dramatic reduction in the total cell number, a high mitotic index, and the presence of abnormal mitotic figures. Importantly, we found that Omcg1 disruption results in the lengthening of M phase rather than in a mitotic block. We show that the mitotic delay in Omcg1−/− embryos is associated with neither a dysfunction of the spindle checkpoint nor abnormal global histone modifications. Taken together, these results suggest that Omcg1 is an important regulator of the cell cycle in the preimplantation embryo. PMID:15988037

Glycosylphosphatidylinositol-anchored proteins are required for cell wall synthesis and morphogenesis in Arabidopsis.

PubMed

Gillmor, C Stewart; Lukowitz, Wolfgang; Brininstool, Ginger; Sedbrook, John C; Hamann, Thorsten; Poindexter, Patricia; Somerville, Chris

2005-04-01

Mutations at five loci named PEANUT1-5 (PNT) were identified in a genetic screen for radially swollen embryo mutants. pnt1 cell walls showed decreased crystalline cellulose, increased pectins, and irregular and ectopic deposition of pectins, xyloglucans, and callose. Furthermore, pnt1 pollen is less viable than the wild type, and pnt1 embryos were delayed in morphogenesis and showed defects in shoot and root meristems. The PNT1 gene encodes the Arabidopsis thaliana homolog of mammalian PIG-M, an endoplasmic reticulum-localized mannosyltransferase that is required for synthesis of the glycosylphosphatidylinositol (GPI) anchor. All five pnt mutants showed strongly reduced accumulation of GPI-anchored proteins, suggesting that they all have defects in GPI anchor synthesis. Although the mutants are seedling lethal, pnt1 cells are able to proliferate for a limited time as undifferentiated callus and do not show the massive deposition of ectopic cell wall material seen in pnt1 embryos. The different phenotype of pnt1 cells in embryos and callus suggest a differential requirement for GPI-anchored proteins in cell wall synthesis in these two tissues and points to the importance of GPI anchoring in coordinated multicellular growth.

Biosafe inertization of municipal solid waste incinerator residues by COSMOS technology.

PubMed

Guarienti, Michela; Gianoncelli, Alessandra; Bontempi, Elza; Moscoso Cardozo, Sdenka; Borgese, Laura; Zizioli, Daniela; Mitola, Stefania; Depero, Laura E; Presta, Marco

2014-08-30

Municipal solid waste incinerator (MSWI) residues can generate negative environmental impacts when improperly handled. The COlloidal Silica Medium to Obtain Safe inert (COSMOS) technology represents a new method to stabilize MSWI residues and to produce inert safe material. Here we report the results about aquatic biotoxicity of lixiviated MSWI fly ash and the corresponding inertized COSMOS material using a zebrafish (Danio rerio) embryo toxicity test. Quantitative assessment of waste biotoxicity included evaluation of mortality rate and of different morphological and teratogenous endpoints in zebrafish embryos exposed to tested materials from 3 to 72h post-fertilization. The results demonstrate that lixiviated MSWI fly ash exerts a dose-dependent lethal effect paralleled by dramatic morphological/teratogenous alterations and apoptotic events in the whole embryo body. Similar effects were observed following MSWI fly ash stabilization in classical concrete matrices, demonstrating that the obtained materials are not biologically safe. On the contrary, no significant mortality and developmental defects were observed in zebrafish embryos exposed to COSMOS inert solution. Our results provide the first experimental in vivo evidence that, in contrast with concrete stabilization procedure, COSMOS technology provides a biologically safe inert. Copyright © 2014 Elsevier B.V. All rights reserved.

The Phosphorylated Pathway of Serine Biosynthesis Is Essential Both for Male Gametophyte and Embryo Development and for Root Growth in Arabidopsis[W

PubMed Central

Cascales-Miñana, Borja; Muñoz-Bertomeu, Jesús; Flores-Tornero, María; Anoman, Armand Djoro; Pertusa, José; Alaiz, Manuel; Osorio, Sonia; Fernie, Alisdair R.; Segura, Juan; Ros, Roc

2013-01-01

This study characterizes the phosphorylated pathway of Ser biosynthesis (PPSB) in Arabidopsis thaliana by targeting phosphoserine phosphatase (PSP1), the last enzyme of the pathway. Lack of PSP1 activity delayed embryo development, leading to aborted embryos that could be classified as early curled cotyledons. The embryo-lethal phenotype of psp1 mutants could be complemented with PSP1 cDNA under the control of Pro35S (Pro35S:PSP1). However, this construct, which was poorly expressed in the anther tapetum, did not complement mutant fertility. Microspore development in psp1.1/psp1.1 Pro35S:PSP1 arrested at the polarized stage. The tapetum from these lines displayed delayed and irregular development. The expression of PSP1 in the tapetum at critical stages of microspore development suggests that PSP1 activity in this cell layer is essential in pollen development. In addition to embryo death and male sterility, conditional psp1 mutants displayed a short-root phenotype, which was reverted in the presence of Ser. A metabolomic study demonstrated that the PPSB plays a crucial role in plant metabolism by affecting glycolysis, the tricarboxylic acid cycle, and the biosynthesis of amino acids. We provide evidence of the crucial role of the PPSB in embryo, pollen, and root development and suggest that this pathway is an important link connecting primary metabolism with development. PMID:23771893

Family Contexts and Schooling Disruption among Orphans in Post-Genocide Rwanda

PubMed Central

2014-01-01

This study examines the relationship between orphan status and schooling disruption in post-genocide Rwanda. The results indicate that while non-orphans have more favorable schooling outcomes in two-parent than in single-parent families, the reverse is true among Rwandan orphans. In single-mother households, paternal orphans, i.e. orphans with only a living mother, have better outcomes than their orphan and non-orphan counterparts. In contrast, paternal orphans have worse outcomes than other children in two-parent households, especially in households headed by males. Maternal orphans are more likely to experience schooling disruptions than non-orphans regardless of family structure. The maternal-orphan disadvantage is nevertheless greater in female-headed than in male-headed households. As expected, non-related orphans are more disadvantaged than orphans related to their household heads. However, non-related orphans have a greater disadvantage in two-parent than in single-parent households. The results also suggest that within households, the provision of childcare to children below schooling age is an impediment to orphan’s schooling. These impediments are, however, greater for double-orphans than paternal or maternal orphans. PMID:25035526

The response of Islamic jurisprudence to ectopic pregnancies, frozen embryo implantation and euthanasia.

PubMed

Ghanem, I

1987-07-01

The opinions of the Jurisconsult of Egypt on Islamic law regarding test tube fertilization, embryo transfer and abortion are explained. Test tube babies, if not derived from the husband's sperm, are by definition, "zina" or the result of illicit sexual intercourse. This type of quasi-adultery is punishable by mere disgracing, rather than lapidation, or stoning to death. Such children cannot inherit even from the mother. Possibly, a female child may marry the husband, to be legitimized in terms of inheritance. Under Islamic law, embryo transfer is illegal insofar as it involves artificial insemination of the donor by the husband; temporary maternity by the donor is a jural concept that has no place in Islamic family law. The egg of the donor, not the surrogate mother, places the issue in the thorny area of multiple suckling. There have been no pronouncements by Islamic legal experts on euthanasia or pregnancy by in vitro fertilization of orphaned embryos. Abortion law "ijhad" in Kuwait was amended in 1982 to permit abortion where either grievous bodily harm to the mother is imminent or it is proved that the baby will suffer incurable brain damage or severe mental retardation. The decision must be approved unanimously by 3 Muslim consultant physicians presided over by an obstetrician or gynecologist, parental consent is required, and the hospital must have an obstetric-gynecological wing. There is precedent in Islamic law for saving the life of the mother where there is a clear choice of allowing either the fetus or the mother to survive. Similarly in case of miscarriage or attempted miscarriage, damages for a fetus or stillborn are less than those paid for a live birth. Penalties for therapeutic abortion, for example after exposure to German measles, have been viewed as less serious before 120 days of gestation, when the Prophet indicated that the embryo is given a soul. These ethical interpretations are worth considering for Western jurists as a source of ideas.

Essential but partially redundant roles for POU4F1/Brn-3a and POU4F2/Brn-3b transcription factors in the developing heart

PubMed Central

Maskell, Lauren J; Qamar, Kashif; Babakr, Aram A; Hawkins, Thomas A; Heads, Richard J; Budhram-Mahadeo, Vishwanie S

2017-01-01

Congenital heart defects contribute to embryonic or neonatal lethality but due to the complexity of cardiac development, the molecular changes associated with such defects are not fully understood. Here, we report that transcription factors (TFs) Brn-3a (POU4F1) and Brn-3b (POU4F2) are important for normal cardiac development. Brn-3a directly represses Brn-3b promoter in cardiomyocytes and consequently Brn-3a knockout (KO) mutant hearts express increased Brn-3b mRNA during mid-gestation, which is linked to hyperplastic growth associated with elevated cyclin D1, a known Brn-3b target gene. However, during late gestation, Brn-3b can cooperate with p53 to enhance transcription of pro-apoptotic genes e.g. Bax, thereby increasing apoptosis and contribute to morphological defects such as non-compaction, ventricular wall/septal thinning and increased crypts/fissures, which may cause lethality of Brn-3a KO mutants soon after birth. Despite this, early embryonic lethality in e9.5 double KO (Brn-3a−/− : Brn-3b−/−) mutants indicate essential functions with partial redundancy during early embryogenesis. High conservation between mammals and zebrafish (ZF) Brn-3b (87%) or Brn-3a (76%) facilitated use of ZF embryos to study potential roles in developing heart. Double morphant embryos targeted with morpholino oligonucleotides to both TFs develop significant cardiac defects (looping abnormalities and valve defects) suggesting essential roles for Brn-3a and Brn-3b in developing hearts. PMID:28594399

Decreased Dissolution of ZnO by Iron Doping Yields Nanoparticles with Reduced Toxicity in the Rodent Lung and Zebrafish Embryos

PubMed Central

Xia, Tian; Zhao, Yan; Sager, Tina; George, Saji; Pokhrel, Suman; Li, Ning; Schoenfeld, David; Meng, Huan; Lin, Sijie; Wang, Xiang; Wang, Meiying; Ji, Zhaoxia; Zink, Jeffrey I.; Mädler, Lutz; Castranova, Vincent; Lin, Shuo; Nel, Andre E.

2014-01-01

We have recently shown that the dissolution of ZnO nanoparticles and Zn2+ shedding leads to a series of sub-lethal and lethal toxicological responses at cellular level that can be alleviated by iron-doping. Iron-doping changes the particle matrix and slows the rate of particle dissolution. To determine whether iron doping of ZnO also leads to lesser toxic effects in vivo, toxicity studies were performed in rodent and zebrafish models. First, we synthesized a fresh batch of ZnO nanoparticles doped with 1–10 wt % of Fe. These particles were extensively characterized to confirm their doping status, reduced rate of dissolution in an exposure medium and reduced toxicity in a cellular screen. Subsequent studies compared the effects of undoped to doped particles in the rat lung, mouse lung and the zebrafish embryo. The zebrafish studies looked at embryo hatching and mortality rates as well as the generation of morphological defects, while the endpoints in the rodent lung included an assessment of inflammatory cell infiltrates, LDH release and cytokine levels in the bronchoalveolar lavage fluid. Iron doping, similar to the effect of the metal chelator, DTPA, interfered in the inhibitory effects of Zn2+ on zebrafish hatching. In the oropharyngeal aspiration model in the mouse, iron doping was associated with decreased polymorphonuclear cell counts and IL-6 mRNA production. Doped particles also elicited decreased heme oxygenase 1 expression in the murine lung. In the intratracheal instillation studies in the rat, Fe-doping was associated with decreased polymorphonuclear cell counts, LDH and albumin levels. All considered, the above data show that Fe-doping is a possible safe design strategy for preventing ZnO toxicity in animals and the environment. PMID:21250651

Rescue of the mouse DDK syndrome by parent-of-origin-dependent modifiers.

PubMed

Ideraabdullah, Folami Y; Kim, Kuikwon; Pomp, Daniel; Moran, Jennifer L; Beier, David; de Villena, Fernando Pardo-Manuel

2007-02-01

When females of the DDK inbred mouse strain are mated to males of other strains, 90-100% of the resulting embryos die during early embryonic development. This DDK syndrome lethality results from incompatibility between an ooplasmic DDK factor and a non-DDK paternal gene, which map to closely linked loci on chromosome 11. It has been proposed that the expression of the gene that encodes the ooplasmic factor is subject to allelic exclusion in oocytes. Previous studies have demonstrated the existence of recessive modifiers that increase lethality in the C57BL/6 and BALB/c strains. These modifiers are thought to skew the choice of allele undergoing allelic exclusion in the oocytes of heterozygous females. In the present study, we demonstrate the presence of modifiers in three Mus musculus domesticus wild-derived strains, PERA, PERC, and RBA. These modifiers completely rescued DDK syndrome lethality. We mapped the major locus that is responsible for rescue in PERA and PERC crosses to proximal chromosome 13 and named this locus Rmod1 (Rescue Modifier of the DDK Syndrome 1). Our experiments demonstrate that PERA or PERC alleles at Rmod1 rescue lethality independently of allelic exclusion. In addition, rescue of the lethal phenotype depends on the parental origin of the Rmod1 alleles; transmission through the dam leads to rescue, while transmission through the sire has no effect.

Developmental and polyamine metabolism alterations in Rhinella arenarum embryos exposed to the organophosphate chlorpyrifos.

PubMed

Sotomayor, Verónica; Lascano, Cecilia; de D'Angelo, Ana María Pechen; Venturino, Andrés

2012-09-01

Organophosphorus pesticides (OPs) are widely applied in the Alto Valle of Río Negro and Neuquén, Argentina, due to intensive fruit growing. Amphibians are particularly sensitive to environmental pollution, and OPs may transiently accumulate in ponds and channels of the region during their reproductive season. Organophosphorus pesticide exposure may alter amphibian embryonic development and the reproductive success of autochthonous species. In the present study, embryos of the common toad Rhinella arenarum were employed to assess developmental alterations and to study polyamine metabolism, which is essential to normal growth, as a possible target underlying the effects of the OP chlorpyrifos. As the duration of chlorpyrifos exposure increased and embryonic development progressed, the median lethal concentration (LC50) values decreased, and the percentage of malformed embryos increased. Developmental arrest was also observed and several morphological alterations were recorded, such as incomplete and abnormal closure of the neural tube, dorsal curvature of the caudal fin, reduction of body size and caudal fin length, atrophy, and edema. An early decrease in ornithine decarboxylase (ODC) activity and polyamine levels was also observed in embryos exposed to chlorpyrifos. The decrease in polyamine contents in tail bud embryos might be a consequence of the reduction in ODC activity. The alteration of polyamine metabolism occurred before embryonic growth was interrupted and embryonic malformations were observed and may be useful as a biomarker in environmental studies. Copyright © 2012 SETAC.

Patterns of protein synthesis in oocytes and early embryos of Rana esculenta complex.

PubMed

Chen, P S; Stumm-Zollinger, E

1986-01-01

We have used isotopic labelling and both one-and two-dimensional electrophoretic procedures to analyse the protien synthesis patterns in oocytes and early embryos of three phenotypes of the European green frogs. The results demonstrated that protein patterns of Rana ridibunda and R. esculenta are identical, but that they differ from those of R. lessonae. Progeny of the lethal cross R. esculenta × R. esculenta showed a distinct delay in the appearance of stage-specific proteins during early embryogenesis. The heat-shock response of R. ridibunda and R. esculenta oocytes was found to be identical, but different from that of Xenopus laevis. The implications of these findings, with respect to hybridogenesis in R. esculenta complex and variations in the regulations of heat shock genes in different amphibian species, are discussed.

Subacute developmental exposure of zebrafish to the organophosphate pesticide metabolite, chlorpyrifos-oxon, results in defects in Rohon-Beard sensory neuron development

PubMed Central

Jacobson, Saskia M.; Birkholz, Denise A.; McNamara, Marcy L.; Bharate, Sandip B.; George, Kathleen M.

2010-01-01

Organophosphate pesticides (OPs) are environmental toxicants known to inhibit the catalytic activity of acetylcholinesterase (AChE) resulting in hypercholinergic toxicity symptoms. In developing embryos, OPs have been hypothesized to affect both cholinergic and non-cholinergic pathways. In order to understand the neurological pathways affected by OP exposure during embryogenesis, we developed a subacute model of OP developmental exposure in zebrafish by exposing embryos to a dose of the OP metabolite chlorpyrifos oxon (CPO) that is non-lethal and significantly inhibited AChE enzymatic activity compared to control embryos (43% at 1 day post-fertilization (dpf) and 11% at 2 dpf). Phenotypic analysis of CPO-exposed embryos demonstrated that embryonic growth, as analyzed by gross morphology, was normal in 85% of treated embryos. Muscle fiber formation was similar to control embryos as analyzed by birefringence, and nicotinic acetylcholine receptor (nAChR) cluster formation was quantitatively similar to control embryos as analyzed by α-bungarotoxin staining. These results indicate that partial AChE activity during the early days of zebrafish development is sufficient for general development, muscle fiber, and nAChR development. Rohon-Beard (RB) sensory neurons exhibited aberrant peripheral axon extension and gene expression profiling suggests that several genes responsible for RB neurogenesis are down-regulated. Stability of CPO in egg water at 28.5 °C was determined by HPLC-UV-MS analysis which revealed that the CPO concentration used in our studies hydrolyzes in egg water with a half-life of one day. The result that developmental CPO exposure affected RB neurogenesis without affecting muscle fiber or nAChR cluster formation demonstrates that zebrafish are a strong model system for characterizing subtle neurological pathologies resulting from environmental toxicants. PMID:20701988

Psychological wellbeing of children at public primary schools in Jimma town: An orphan and non-orphan comparative study.

PubMed

Hailegiorgis, Muluken Tigistu; Berheto, Tezera Moshago; Sibamo, Ephrem Lejore; Asseffa, Netsanet Abera; Tesfa, Gashaw; Birhanu, Fitsum

2018-01-01

Orphans face multiple challenges including insufficient food, shelter, schooling, and medical care. Most research on orphans in developing countries concentrates on nutrition and health status. The present study aims to explore the psychological wellbeing of in-school orphaned and non-orphaned children. A comparative cross-sectional study design was used in 370 randomly selected children aged between 10 and 18. Two rosters (one for orphans and one for non-orphans) were created, and then 185 were selected from each roster. Trained field workers used structured questionnaires to obtain information from participants. An adapted Ryff Psychological Wellbeing Scale was used to measure psychological wellbeing. Mean scores were determined for each dimension and for total psychological wellbeing. The mean split was used to divide psychological wellbeing into "high" and "low". Data were coded, entered, cleaned, and analyzed using SPSS version 20. The independent sample t-test was used to determine statistically significant differences in psychological wellbeing between orphaned and non-orphaned children. P values < 0.05 were deemed statistically significant. Of 370 children, 185 (50%) were orphans. Among orphaned children, only 62 (33.5%) scored high on the total psychological wellbeing scale whereas 107 (57.8%) of their non-orphaned peers scored highly. The non-orphaned children had about 10.8 higher mean psychological wellbeing scores than their orphan counterparts (P<0.001). The mean (±SD) psychological wellbeing of the non-orphaned children was 164.0 (17.2) vs. 153.2 (17.2) in the orphaned group. The psychological wellbeing of orphans is significantly lower than their non-orphaned peers. Orphan support projects must consider psychosocial wellbeing in addition to material support.

Psychological wellbeing of children at public primary schools in Jimma town: An orphan and non-orphan comparative study

PubMed Central

Hailegiorgis, Muluken Tigistu; Berheto, Tezera Moshago; Sibamo, Ephrem Lejore; Tesfa, Gashaw; Birhanu, Fitsum

2018-01-01

Introduction Orphans face multiple challenges including insufficient food, shelter, schooling, and medical care. Most research on orphans in developing countries concentrates on nutrition and health status. The present study aims to explore the psychological wellbeing of in-school orphaned and non-orphaned children. Method A comparative cross-sectional study design was used in 370 randomly selected children aged between 10 and 18. Two rosters (one for orphans and one for non-orphans) were created, and then 185 were selected from each roster. Trained field workers used structured questionnaires to obtain information from participants. An adapted Ryff Psychological Wellbeing Scale was used to measure psychological wellbeing. Mean scores were determined for each dimension and for total psychological wellbeing. The mean split was used to divide psychological wellbeing into “high” and “low”. Data were coded, entered, cleaned, and analyzed using SPSS version 20. The independent sample t-test was used to determine statistically significant differences in psychological wellbeing between orphaned and non-orphaned children. P values < 0.05 were deemed statistically significant. Results Of 370 children, 185 (50%) were orphans. Among orphaned children, only 62 (33.5%) scored high on the total psychological wellbeing scale whereas 107 (57.8%) of their non-orphaned peers scored highly. The non-orphaned children had about 10.8 higher mean psychological wellbeing scores than their orphan counterparts (P<0.001). The mean (±SD) psychological wellbeing of the non-orphaned children was 164.0 (17.2) vs. 153.2 (17.2) in the orphaned group. Conclusion The psychological wellbeing of orphans is significantly lower than their non-orphaned peers. Orphan support projects must consider psychosocial wellbeing in addition to material support. PMID:29649248

An enumeration of orphans and analysis of the problems and wishes of orphans: the case of Kariba, Zimbabwe.

PubMed

Mangoma, Jaqualine; Chimbari, Moses; Dhlomo, Elmon

2008-09-01

In southern Africa, HIV and AIDS accounts for the largest proportion of orphans. Very often the orphaned children become destitute, and young girls in particular become more vulnerable to HIV and AIDS as they try to fend for the rest of the family. This paper reports on the number of orphans in Kariba, Zimbabwe, describing their problems, coping strategies and wishes. The study was carried out in Nyamhunga and Mahombekombe high-density residential areas of Kariba, Zimbabwe. All households in the study area were visited, and a semi-structured questionnaire aimed at enumerating orphans and obtaining information regarding general problems of orphans was administered to heads of households present. In addition, information on the plight, coping strategies and survival wishes of orphans were collected through 15 focus group discussions held with orphans, care givers, community leaders and stakeholders. The prevalence of orphans in Kariba, based on a sample of 3 976 households, was found to be very high (56%) with most of the orphans in the age group 6-12 years. The majority of the orphans were paternal and under maternal care. Over 30% of the orphans of school-going age were not in school, and some young girl orphans became involved in commercial sex work. The survival wish list of the orphans included school fees, accommodation, health care provision, adequate food and income-generating projects. However, suggestions on orphan care and needs given by community members were somewhat divergent from the orphans' wish list, indicating that community interventions may not be sensitive to the wishes of those affected. Although the study did not categorise orphans according to cause of death of parents, there are indications that most of the orphans are accounted for by HIV and AIDS.

Effects of effects of suspended sediment on early-life stage survival of Yaqui chub, an endangered USA–Mexico borderlands cyprinid

USGS Publications Warehouse

Barkalow, Stephani L. Clark; Bonar, Scott A.

2015-01-01

High levels of total suspended sediment (TSS) can have negative consequences on fishes, such as altering food supply, lowering food acquisition, clogging gills, and disrupting reproduction. While effects of TSS on salmonids and estuarine fish are well studied, less is known about possible negative impacts of suspended sediment on desert fishes. Several imperiled desert fishes inhabit streams and springs near the U.S.–Mexico border and are potentially threatened by increased sediment loads from borderlands activity such as livestock grazing, road building, illegal traffic, and law enforcement patrols. One such species is the Yaqui Chub Gila purpurea, a federally listed endangered cyprinid. We exposed Yaqui Chub embryos and fry (mean TL = 12.6 mm; SE = 0.42) to a range of TSS levels commonly found in one of the only streams they inhabit, Black Draw, which crosses the Arizona–Mexico border. We tested effects of 0; 300; 500; 1,000; 5,000; and 10,000 mg/L TSS loads on fry and embryos over a 5-d period in three replicate containers for each treatment. Fifty percent hatch rate (i.e., median lethal concentration, LC50) was 3,977 mg/L for embryos. The LC50 for fry (concentration at which half died) was 8,372 mg/L after 12 h of exposure; however, after 5-d exposure, LC50 leveled at 1,197 mg/L. The TL of fry did not change significantly in any treatment over the 5-d period. Suspended sediment in Black Draw reached concentrations lethal to Yaqui Chub embryo and fry during four floods in 2012. Although some desert fishes have evolved in rivers and streams subject to elevated TSS and are tolerant to high TSS concentrations, other fish species are less tolerant and may be impacted by land practices which increase erosion into stream systems. Management of critically endangered desert fishes should include considerations of the effects of increased suspended sediment.

Issues surrounding orphan disease and orphan drug policies in Europe.

PubMed

Denis, Alain; Mergaert, Lut; Fostier, Christel; Cleemput, Irina; Simoens, Steven

2010-01-01

An orphan disease is a disease with a very low prevalence. Although there are 5000-7000 orphan diseases, only 50 orphan drugs (i.e. drugs developed to treat orphan diseases) were marketed in the EU by the end of 2008. In 2000, the EU implemented policies specifically designed to stimulate the development of orphan drugs. While decisions on orphan designation and the marketing authorization of orphan drugs are made at the EU level, decisions on drug reimbursement are made at the member state level. The specific features of orphan diseases and orphan drugs make them a high-priority issue for policy makers. The aim of this article is to identify and discuss several issues surrounding orphan disease and drug policies in Europe. The present system of orphan designation allows for drugs for non-orphan diseases to be designated as orphan drugs. The economic factors underlying orphan designation can be questioned in some cases, as a low prevalence of a certain indication does not equal a low return on investment for the drug across its indications. High-quality evidence about the clinical added value of orphan drugs is rarely available at the time of marketing authorization, due to the low number of patients. A balance must be struck between ethical and economic concerns. To this effect, there is a need to initiate a societal dialogue on this issue, to clarify what society wants and accepts in terms of ethical and economic consequences. The growing budgetary impact of orphan drugs puts pressure on drug expenditure. Indications can be extended for an orphan drug and the total prevalence across indications is not considered. Finally, cooperation needs to be fostered in the EU, particularly through a standardized approach to the creation and use of registries. These issues require further attention from researchers, policy makers, health professionals, patients, pharmaceutical companies and other stakeholders with a view to optimizing orphan disease and drug policies in Europe.

FACTORS ASSOCIATED WITH INTERNALISING PROBLEMS IN ORPHANS AND THEIR CAREGIVERS IN RURAL MOZAMBIQUE.

PubMed

Libombo, P; Baker-Henningham, H; Grantham-McGregor, S

2012-01-01

To compare internalising problems reported by orphans and their caregivers with that of non-orphans and their caregivers. Case control study. Cahora-Bassa District of Tete, Mozambique Seventy-six maternal or double orphans (aged 10-14 years) and their caregivers were compared with seventy-four non-orphans and their caregivers living in the same neighbourhood. children were interviewed with a semi-structured questionnaire concerning their internalising problems, family structure, school attendance, daily experiences and perceived problems. The children's primary caregivers were also interviewed concerning their depressive symptoms, available social support, socio-economic conditions and perceived problems. Orphans lived in poorer households than non-orphans and reported more internalising symptoms and more economic and psychosocial disadvantages. Orphan caregivers were more depressed and had less social support than non-orphan caregivers. Child internalising symptoms were independently associated with bullying (B = 8.04, 95% CI: 0.24,15.85), perceived undeserved punishment (B = 11.98, 95% CI: S.98,17.98) and orphan status (B = 33.36, 95% CI: 26.67, 40.05). The effect of punishment was stronger for orphans than non-orphans. Frequency of hunger affected internalising symptoms only in orphans. Caregiver depression was independently associated with low social support (B = -0.35, 95% CI: -0.51, -0.18), few possessions (B = -2.10, 95% CI: -3.42, -0.79) an orphan status (B = 4.54, 95% CI: 3.30, 5.78) and possessions had a stronger effect in orphan caregivers. Quality of housing caused depression only in caregivers of orphans. Both orphans and their caregivers were more depressed than the non-orphans and their caregivers. They were exposed to more economic and psychosocial disadvantages and were more vulnerable to risks.

Pharmaceutical expenditure on drugs for rare diseases in Canada: a historical (2007-13) and prospective (2014-18) MIDAS sales data analysis.

PubMed

Divino, Victoria; DeKoven, Mitch; Kleinrock, Michael; Wade, Rolin L; Kim, Tony; Kaura, Satyin

2016-05-21

Health Canada has defined rare diseases as life-threatening, seriously debilitating, or serious chronic conditions affecting a very small number of patients (~1 in 2,000 persons). An estimated 9 % of Canadians suffer from a rare disease. Drugs treating rare diseases (DRDs) are also known as orphan drugs. While Canada is currently developing an orphan drug framework, in the United States (US), the Orphan Drug Act (ODA) of 1983 established incentives for the development of orphan drugs. This study measured total annual expenditure of orphan drugs in Canada (2007-13) and estimated future (2014-18) orphan drug expenditure. Orphan drugs approved by the US Food and Drug Administration (FDA) in the US were used as a proxy for the orphan drug landscape in Canada. Branded, orphan drugs approved by the FDA between 1983 through 2013 were identified (N = 356 unique products). Only US orphan drugs with the same orphan indication(s) approved in Canada were included in the analysis. Adjustment via an indication factoring was applied to products with both orphan and non-orphan indications using available data sources to isolate orphan-indication sales. The IMS Health MIDAS database of audited biopharmaceutical sales was utilized to measure total orphan drug expenditure, calculated annually from 2007-2013 and evaluated as a proportion of total annual pharmaceutical drug expenditure (adjusted to 2014 CAD). Between 2007 and 2013, expenditure was measured for a final N = 147 orphan drugs. Orphan drug expenditure totaled $610.2 million (M) in 2007 and $1,100.0 M in 2013, representing 3.3- 5.6 % of total Canadian pharmaceutical drug expenditure in 2007-2013, respectively. Future trend analysis suggests orphan drug expenditure will remain under 6 % of total expenditure in 2014-18. While the number of available orphan drugs and associated expenditure increased over time, access remains an issue, and from the perspectives of society and equity, overall spending on orphan drugs is lower relative to the number of patients affected with an orphan disease in Canada. The overall budget impact of orphan drugs is small and fairly stable relative to total pharmaceutical expenditure. Concerns that growth in orphan drug expenditure may lead to unsustainable drug expenditure do not appear to be justified.

Novel Metrics to Characterize Embryonic Elongation of the Nematode Caenorhabditis elegans.

PubMed

Martin, Emmanuel; Rocheleau-Leclair, Olivier; Jenna, Sarah

2016-03-28

Dissecting the signaling pathways that control the alteration of morphogenic processes during embryonic development requires robust and sensitive metrics. Embryonic elongation of the nematode Caenorhabditis elegans is a late developmental stage consisting of the elongation of the embryo along its longitudinal axis. This developmental stage is controlled by intercellular communication between hypodermal cells and underlying body-wall muscles. These signaling mechanisms control the morphology of hypodermal cells by remodeling the cytoskeleton and the cell-cell junctions. Measurement of embryonic lethality and developmental arrest at larval stages as well as alteration of cytoskeleton and cell-cell adhesion structures in hypodermal and muscle cells are classical phenotypes that have been used for more than 25 years to dissect these signaling pathways. Recent studies required the development of novel metrics specifically targeting either early or late elongation and characterizing morphogenic defects along the antero-posterior axis of the embryo. Here, we provide detailed protocols enabling the accurate measurement of the length and the width of the elongating embryos as well as the length of synchronized larvae. These methods constitute useful tools to identify genes controlling elongation, to assess whether these genes control both early and late phases of this stage and are required evenly along the antero-posterior axis of the embryo.

Assessing Aromatic-Hydrocarbon Toxicity to Fish Early Life Stages Using Passive-Dosing Methods and Target-Lipid and Chemical-Activity Models.

PubMed

Butler, Josh D; Parkerton, Thomas F; Redman, Aaron D; Letinski, Daniel J; Cooper, Keith R

2016-08-02

Aromatic hydrocarbons (AH) are known to impair fish early life stages (ELS). However, poorly defined exposures often confound ELS-test interpretation. Passive dosing (PD) overcomes these challenges by delivering consistent, controlled exposures. The objectives of this study were to apply PD to obtain 5 d acute embryo lethality and developmental data and 30 d chronic embryo-larval survival and growth-effects data using zebrafish with different AHs; to analyze study and literature toxicity data using target-lipid (TLM) and chemical-activity (CA) models; and to extend PD to a mixture and test the assumption of AH additivity. PD maintained targeted exposures over a concentration range of 6 orders of magnitude. AH toxicity increased with log Kow up to pyrene (5.2). Pericardial edema was the most sensitive sublethal effect that often preceded embryo mortality, although some AHs did not produce developmental effects at concentrations causing mortality. Cumulative embryo-larval mortality was more sensitive than larval growth, with acute-to-chronic ratios of <10. More-hydrophobic AHs did not exhibit toxicity at aqueous saturation. The relationship and utility of the TLM-CA models for characterizing fish ELS toxicity is discussed. Application of these models indicated that concentration addition provided a conservative basis for predicting ELS effects for the mixture investigated.

Screening of Toxic Effects of Bisphenol A and Products of Its Degradation: Zebrafish (Danio rerio) Embryo Test and Molecular Docking.

PubMed

Makarova, Katerina; Siudem, Pawel; Zawada, Katarzyna; Kurkowiak, Justyna

2016-10-01

Bisphenol A (BPA) acts as an endocrine-disrupting compound even at a low concentration. Degradation of BPA could lead to the formation of toxic products. In this study, we compare the toxicity of BPA and seven intermediate products of its degradation. The accuracy of three molecular docking programs (Surflex, Autodock, and Autodock Vina) in predicting the binding affinities of selected compounds to human (ERα, ERβ, and ERRγ) and zebrafish (ERα, ERRγA, and ERRγB) estrogen and estrogen-related receptors was evaluated. The docking experiments showed that 4-isopropylphenol could have similar toxicity to that of BPA due to its high affinity to ERRγ and ERRγB and high octanol-water partitioning coefficient. The least toxic compounds were hydroquinone and phenol. Those compounds as well as BPA were screened in the zebrafish (Danio rerio) embryo test. 4-isopropylphenol had the strongest toxic effect on zebrafish embryos and caused 100% lethality shortly after exposure. BPA caused the delay in development, multiple deformations, and low heartbeats (30 bps), whereas hydroquinone had no impact on the development of the zebrafish embryo. Thus, the results of zebrafish screening are in good agreement with our docking experiment. The molecular docking could be used to screen the toxicity of other xenoestrogens and their products of degradation.

The RNA-Editing Enzyme ADAR1 Controls Innate Immune Responses to RNA

PubMed Central

Mannion, Niamh M.; Greenwood, Sam M.; Young, Robert; Cox, Sarah; Brindle, James; Read, David; Nellåker, Christoffer; Vesely, Cornelia; Ponting, Chris P.; McLaughlin, Paul J.; Jantsch, Michael F.; Dorin, Julia; Adams, Ian R.; Scadden, A.D.J.; Öhman, Marie; Keegan, Liam P.; O’Connell, Mary A.

2014-01-01

Summary The ADAR RNA-editing enzymes deaminate adenosine bases to inosines in cellular RNAs. Aberrant interferon expression occurs in patients in whom ADAR1 mutations cause Aicardi-Goutières syndrome (AGS) or dystonia arising from striatal neurodegeneration. Adar1 mutant mouse embryos show aberrant interferon induction and die by embryonic day E12.5. We demonstrate that Adar1 embryonic lethality is rescued to live birth in Adar1; Mavs double mutants in which the antiviral interferon induction response to cytoplasmic double-stranded RNA (dsRNA) is prevented. Aberrant immune responses in Adar1 mutant mouse embryo fibroblasts are dramatically reduced by restoring the expression of editing-active cytoplasmic ADARs. We propose that inosine in cellular RNA inhibits antiviral inflammatory and interferon responses by altering RLR interactions. Transfecting dsRNA oligonucleotides containing inosine-uracil base pairs into Adar1 mutant mouse embryo fibroblasts reduces the aberrant innate immune response. ADAR1 mutations causing AGS affect the activity of the interferon-inducible cytoplasmic isoform more severely than the nuclear isoform. PMID:25456137

The RNA-editing enzyme ADAR1 controls innate immune responses to RNA.

PubMed

Mannion, Niamh M; Greenwood, Sam M; Young, Robert; Cox, Sarah; Brindle, James; Read, David; Nellåker, Christoffer; Vesely, Cornelia; Ponting, Chris P; McLaughlin, Paul J; Jantsch, Michael F; Dorin, Julia; Adams, Ian R; Scadden, A D J; Ohman, Marie; Keegan, Liam P; O'Connell, Mary A

2014-11-20

The ADAR RNA-editing enzymes deaminate adenosine bases to inosines in cellular RNAs. Aberrant interferon expression occurs in patients in whom ADAR1 mutations cause Aicardi-Goutières syndrome (AGS) or dystonia arising from striatal neurodegeneration. Adar1 mutant mouse embryos show aberrant interferon induction and die by embryonic day E12.5. We demonstrate that Adar1 embryonic lethality is rescued to live birth in Adar1; Mavs double mutants in which the antiviral interferon induction response to cytoplasmic double-stranded RNA (dsRNA) is prevented. Aberrant immune responses in Adar1 mutant mouse embryo fibroblasts are dramatically reduced by restoring the expression of editing-active cytoplasmic ADARs. We propose that inosine in cellular RNA inhibits antiviral inflammatory and interferon responses by altering RLR interactions. Transfecting dsRNA oligonucleotides containing inosine-uracil base pairs into Adar1 mutant mouse embryo fibroblasts reduces the aberrant innate immune response. ADAR1 mutations causing AGS affect the activity of the interferon-inducible cytoplasmic isoform more severely than the nuclear isoform. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Effects of oxytetracycline and amoxicillin on development and biomarkers activities of zebrafish (Danio rerio).

PubMed

Oliveira, Rhaul; McDonough, Sakchai; Ladewig, Jessica C L; Soares, Amadeu M V M; Nogueira, António J A; Domingues, Inês

2013-11-01

Antibiotics have been widely used in human and veterinary medicine to treat or prevent diseases. Residues of antibiotics have been found in aquatic environments, but their effects on fish have been not properly investigated. This work aimed to assess the sub-lethal effects of oxytetracycline and amoxicillin on zebrafish development and biomarkers. Embryos and adults were exposed during 96 h to amoxicillin and oxytetracycline following OECD guidelines. Tissues of adults and pools of embryos were used for catalase, glutathione-S-transferases and lactate dehydrogenase determinations. Amoxicillin caused premature hatching (48 h-EC50=132.4 mg/l) whereas oxytetracycline cause delayed hatching of embryos (72 h-EC50=127.6 mg/l). Moreover, both antibiotics inhibited catalase and induced glutathione-S-transferases in zebrafish adults. However, only oxytetracycline induced lactate dehydrogenase. Short-term effects of antibiotics were observed at high doses (mg/l) indicating that physiological impairment in fish populations is unlike to occur. However, effects of chronic exposures to low doses of ABs must be investigated. Copyright © 2013 Elsevier B.V. All rights reserved.

Physical and sexual abuse in orphaned compared to non-orphaned children in sub-Saharan Africa: A systematic review and meta-analysis

PubMed Central

Nichols, J.; Embleton, L.; Mwangi, A.; Morantz, G.; Vreeman, R.; Ayaya, S.; Ayuku, D.; Braitstein, P.

2013-01-01

This systematic review assessed the quantitative literature to determine whether orphans are more likely to experience physical and/or sexual abuse compared to non-orphans in sub-Saharan Africa (SSA). It also evaluated the quality of evidence and identified research gaps. Our search identified 10 studies, all published after 2005, from Zimbabwe, South Africa, Kenya and Uganda. The studies consisted of a total 17,336 participants (51% female and 58% non-orphans). Of those classified as orphans (n = 7,315), 73% were single orphans, and 27% were double orphans. The majority of single orphans were paternal orphans (74%). Quality assessment revealed significant variability in the quality of the studies, although most scored higher for general design than dimensions specific to the domain of orphans and abuse. Combined estimates of data suggested that, compared to non-orphans, orphans are not more likely to experience physical abuse (combined OR = 0.96, 95% CI [0.79, 1.16]) or sexual abuse (combined OR = 1.25, 95% CI [0.88, 1.78]). These data suggest that orphans are not systematically at higher risk of experiencing physical or sexual abuse compared to non-orphans in sub-Saharan Africa. However, because of inconsistent quality of data and reporting, these findings should be interpreted with caution. Several recommendations are made for improving data quality and reporting consistency on this important issue. PMID:24210283

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, W.F.; Martinell, J.; Whitney, J.B. III

The group of diseases called the thalassemias is the largest single-gene health problem in the world according the World Health Organization. The thalassemias are lethal hereditary anemias in which the infants cannot make their own blood. Three mouse mutants are shown to be models of the human disease ..cap alpha..-thalassemia. However, since an additional gene is affected, these mutants represent a particularly severe condition in which death occurs in the homozygous embryo even before globin genes are activated. Phenotypic and genotypic characteristics are described. (ACR)

Abnormal differentiation, hyperplasia and embryonic/perinatal lethality in BK5-T/t transgenic mice

PubMed Central

Chen, Xin; Schneider-Broussard, Robin; Hollowell, Debra; McArthur, Mark; Jeter, Collene R.; Benavides, Fernando; DiGiovanni, John; Tang, Dean G.

2009-01-01

The cell-of-origin has a great impact on the types of tumors that develop and the stem/progenitor cells have long been considered main targets of malignant transformation. The SV40 large T and small t antigens (T/t), have been targeted to multiple differentiated cellular compartments in transgenic mice. In most of these studies, transgenic animals develop tumors without apparent defects in animal development. In this study, we used the bovine keratin 5 (BK5) promoter to target the T/t antigens to stem/progenitor cell-containing cytokeratin 5 (CK5) cellular compartment. A transgene construct, BK5-T/t, was made and microinjected into the male pronucleus of FVB/N mouse oocytes. After implanting ∼1700 embryos, only 7 transgenics were obtained, including 4 embryos (E9.5, E13, E15, and E20) and 3 postnatal animals, which died at P1, P2, and P18, respectively. Immunohistological analysis revealed aberrant differentiation and prominent hyperplasia in several transgenic CK5 tissues, especially the upper digestive organs (tongue, oral mucosa, esophagus, and forestomach) and epidermis, the latter of which also showed focal dysplasia. Altogether, these results indicate that constitutive expression of the T/t antigens in CK5 cellular compartment results in abnormal epithelial differentiation and leads to embryonic/perinatal animal lethality. PMID:19272531

Acute toxicity of arsenic and oxidative stress responses in the embryonic development of the common South American toad Rhinella arenarum.

PubMed

Mardirosian, Mariana Noelia; Lascano, Cecilia Inés; Ferrari, Ana; Bongiovanni, Guillermina Azucena; Venturino, Andrés

2015-05-01

Arsenic (As), a natural element of ecological relevance, is found in natural water sources throughout Argentina in concentrations between 0.01 mg/L and 15 mg/L. The autochthonous toad Rhinella arenarum was selected to study the acute toxicity of As and the biochemical responses elicited by the exposure to As in water during its embryonic development. The median lethal concentration (LC50) value averaged 24.3 mg/L As and remained constant along the embryonic development. However, As toxicity drastically decreased when embryos were exposed from heartbeat-stage on day 4 of development, suggesting the onset of detoxification mechanisms. Given the environmental concentrations of As in Argentina, there is a probability of exceeding lethal levels at 1% of sites. Arsenic at sublethal concentrations caused a significant decrease in the total antioxidant potential but generated an increase in endogenous glutathione (GSH) content and glutathione S-transferase (GST) activity. This protective response might prevent a deeper decline in the antioxidant system and further oxidative damage. Alternatively, it might be linked to As conjugation with GSH for its excretion. The authors conclude that toad embryos are more sensitive to As during early developmental stages and that relatively high concentrations of this toxic element are required to elicit mortality, but oxidative stress may be an adverse effect at sublethal concentrations. © 2014 SETAC.

The US Orphan Drug Act: rare disease research stimulator or commercial opportunity?

PubMed

Wellman-Labadie, Olivier; Zhou, Youwen

2010-05-01

This study investigates issues associated with the United States Orphan Drug Act. A comprehensive orphan drug database was compiled from FDA data and corporate annual reports of major pharmaceutical companies. Analysis allowed the generation of a descriptive orphan drug portrait as well as documentation of orphan drugs along their lifecycle. Currently, 2002 products have obtained orphan drug designation with 352 drugs obtaining FDA approval. Approximately 33% of orphan drugs are oncology products. On average, products obtain 1.7 orphan designations with approximately 70% obtaining a single designation. At least 9% of orphan drugs have reached blockbuster status with two-thirds having two or more designations. An additional 25 orphan drugs had sales exceeding US$ 100 million in 2008 alone. Since 1983, at least 14 previously discontinued products have been recycled as orphan drugs. The United States Orphan Drug Act has created issues which, in some cases, have led to commercial and ethical abuses. Orphan Drug Act reform is necessary but current incentives, including 7 year market exclusivity, should be maintained in order to favour patients as well as economic prosperity. Suggested reforms include price regulation, subsidy paybacks for profitable drugs and the establishment of an International Orphan Drug Office. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

Persisting mental health problems among AIDS-orphaned children in South Africa.

PubMed

Cluver, Lucie D; Orkin, Mark; Gardner, Frances; Boyes, Mark E

2012-04-01

  By 2008, 12 million children in sub-Saharan Africa were orphaned by AIDS. Cross-sectional studies show psychological problems for AIDS-orphaned children, but until now no longitudinal study has explored enduring psychological effects of AIDS-orphanhood in the developing world.   A 4-year longitudinal follow-up of AIDS-orphaned children with control groups of other-orphans and non-orphans. 1021 children (M = 13.4 years, 50% female, 98% isiXhosa-speaking) were interviewed in 2005 and followed up in 2009 with 71% retention (49% female, M = 16.9 years), in poor urban South African settlements. Children were interviewed using sociodemographic questionnaires and well-validated standardised scales for assessing depression, anxiety, and post-traumatic stress. Data were analysed using mixed-design ANOVA and backward-stepping regression.   AIDS-orphaned children showed higher depression, anxiety, and post-traumatic stress disorder (PTSD) scores in both 2005 and 2009 when compared with other-orphans and non-orphans. Backward-stepping regression, controlling for baseline mental health, and sociodemographic cofactors such as age, gender, and type of bereavement, revealed that being AIDS-orphaned in 2005 was associated with depression, anxiety, and PTSD scores in 2009. This was not the case for other-orphaned or non-orphaned children. Age interacted with orphan status, such that there was a steep rise in psychological distress in the AIDS-orphaned group, but no rise with age amongst other-orphans and non-orphans.   Negative mental health outcomes amongst AIDS-orphaned children are maintained and worsen over a 4-year period. It is important that psychosocial support programmes are sustained, and focus on youth as well as young children. © 2011 The Authors. Journal of Child Psychology and Psychiatry © 2011 Association for Child and Adolescent Mental Health.

The Choline/Ethanolamine Kinase Family in Arabidopsis: Essential Role of CEK4 in Phospholipid Biosynthesis and Embryo Development

PubMed Central

2015-01-01

Phospholipids are highly conserved and essential components of biological membranes. The major phospholipids, phosphatidylethanolamine and phosphatidylcholine (PtdCho), are synthesized by the transfer of the phosphoethanolamine or phosphocholine polar head group, respectively, to the diacylglycerol backbone. The metabolism of the polar head group characterizing each phospholipid class is poorly understood; thus, the biosynthetic pathway of major phospholipids remains elusive in Arabidopsis thaliana. The choline/ethanolamine kinase (CEK) family catalyzes the initial steps of phospholipid biosynthesis. Here, we analyzed the function of the four CEK family members present in Arabidopsis. Knocking out of CEK4 resulted in defective embryo development, which was complemented by transformation of genomic CEK4. Reciprocal genetic crossing suggested that CEK4 knockout causes embryonic lethality, and microscopy analysis of the aborted embryos revealed developmental arrest after the heart stage, with no defect being found in the pollen. CEK4 is preferentially expressed in the vasculature, organ boundaries, and mature embryos, and CEK4 was mainly localized to the plasma membrane. Overexpression of CEK4 in wild-type Arabidopsis increased the levels of PtdCho in seedlings and mature siliques and of major membrane lipids in seedlings and triacylglycerol in mature siliques. CEK4 may be the plasma membrane-localized isoform of the CEK family involved in the rate-limiting step of PtdCho biosynthesis and appears to be required for embryo development in Arabidopsis. PMID:25966764

POPCORN functions in the auxin pathway to regulate embryonic body plan and meristem organization in Arabidopsis.

PubMed

Xiang, Daoquan; Yang, Hui; Venglat, Prakash; Cao, Yongguo; Wen, Rui; Ren, Maozhi; Stone, Sandra; Wang, Edwin; Wang, Hong; Xiao, Wei; Weijers, Dolf; Berleth, Thomas; Laux, Thomas; Selvaraj, Gopalan; Datla, Raju

2011-12-01

The shoot and root apical meristems (SAM and RAM) formed during embryogenesis are crucial for postembryonic plant development. We report the identification of POPCORN (PCN), a gene required for embryo development and meristem organization in Arabidopsis thaliana. Map-based cloning revealed that PCN encodes a WD-40 protein expressed both during embryo development and postembryonically in the SAM and RAM. The two pcn alleles identified in this study are temperature sensitive, showing defective embryo development when grown at 22°C that is rescued when grown at 29°C. In pcn mutants, meristem-specific expression of WUSCHEL (WUS), CLAVATA3, and WUSCHEL-RELATED HOMEOBOX5 is not maintained; SHOOTMERISTEMLESS, BODENLOS (BDL) and MONOPTEROS (MP) are misexpressed. Several findings link PCN to auxin signaling and meristem function: ectopic expression of DR5(rev):green fluorescent protein (GFP), pBDL:BDL-GFP, and pMP:MP-β-glucuronidase in the meristem; altered polarity and expression of pPIN1:PIN1-GFP in the apical domain of the developing embryo; and resistance to auxin in the pcn mutants. The bdl mutation rescued embryo lethality of pcn, suggesting that improper auxin response is involved in pcn defects. Furthermore, WUS, PINFORMED1, PINOID, and TOPLESS are dosage sensitive in pcn, suggesting functional interaction. Together, our results suggest that PCN functions in the auxin pathway, integrating auxin signaling in the organization and maintenance of the SAM and RAM.

POPCORN Functions in the Auxin Pathway to Regulate Embryonic Body Plan and Meristem Organization in Arabidopsis[W][OA

PubMed Central

Xiang, Daoquan; Yang, Hui; Venglat, Prakash; Cao, Yongguo; Wen, Rui; Ren, Maozhi; Stone, Sandra; Wang, Edwin; Wang, Hong; Xiao, Wei; Weijers, Dolf; Berleth, Thomas; Laux, Thomas; Selvaraj, Gopalan; Datla, Raju

2011-01-01

The shoot and root apical meristems (SAM and RAM) formed during embryogenesis are crucial for postembryonic plant development. We report the identification of POPCORN (PCN), a gene required for embryo development and meristem organization in Arabidopsis thaliana. Map-based cloning revealed that PCN encodes a WD-40 protein expressed both during embryo development and postembryonically in the SAM and RAM. The two pcn alleles identified in this study are temperature sensitive, showing defective embryo development when grown at 22°C that is rescued when grown at 29°C. In pcn mutants, meristem-specific expression of WUSCHEL (WUS), CLAVATA3, and WUSCHEL-RELATED HOMEOBOX5 is not maintained; SHOOTMERISTEMLESS, BODENLOS (BDL) and MONOPTEROS (MP) are misexpressed. Several findings link PCN to auxin signaling and meristem function: ectopic expression of DR5rev:green fluorescent protein (GFP), pBDL:BDL-GFP, and pMP:MP-β-glucuronidase in the meristem; altered polarity and expression of pPIN1:PIN1-GFP in the apical domain of the developing embryo; and resistance to auxin in the pcn mutants. The bdl mutation rescued embryo lethality of pcn, suggesting that improper auxin response is involved in pcn defects. Furthermore, WUS, PINFORMED1, PINOID, and TOPLESS are dosage sensitive in pcn, suggesting functional interaction. Together, our results suggest that PCN functions in the auxin pathway, integrating auxin signaling in the organization and maintenance of the SAM and RAM. PMID:22158464

Comparative analysis of the transcriptome responses of zebrafish embryos after exposure to low concentrations of cadmium, cobalt and copper.

PubMed

Sonnack, Laura; Klawonn, Thorsten; Kriehuber, Ralf; Hollert, Henner; Schäfers, Christoph; Fenske, Martina

2018-03-01

Metal toxicity is a global environmental challenge. Fish are particularly prone to metal exposure, which can be lethal or cause sublethal physiological impairments. The objective of this study was to investigate how adverse effects of chronic exposure to non-toxic levels of essential and non-essential metals in early life stage zebrafish may be explained by changes in the transcriptome. We therefore studied the effects of three different metals at low concentrations in zebrafish embryos by transcriptomics analysis. The study design compared exposure effects caused by different metals at different developmental stages (pre-hatch and post-hatch). Wild-type embryos were exposed to solutions of low concentrations of copper (CuSO 4 ), cadmium (CdCl 2 ) and cobalt (CoSO 4 ) until 96h post-fertilization (hpf) and microarray experiments were carried out to determine transcriptome profiles at 48 and 96hpf. We found that the toxic metal cadmium affected the expression of more genes at 96hpf than 48hpf. The opposite effect was observed for the essential metals cobalt and copper, which also showed enrichment of different GO terms. Genes involved in neuromast and motor neuron development were significantly enriched, agreeing with our previous results showing motor neuron and neuromast damage in the embryos. Our data provide evidence that the response of the transcriptome of fish embryos to metal exposure differs for essential and non-essential metals. Copyright © 2017 Elsevier Inc. All rights reserved.

Stage-specific apoptosis, developmental delay, and embryonic lethality in mice homozygous for a targeted disruption in the murine Bloom's syndrome gene.

PubMed

Chester, N; Kuo, F; Kozak, C; O'Hara, C D; Leder, P

1998-11-01

Bloom's syndrome is a human autosomal genetic disorder characterized at the cellular level by genome instability and increased sister chomatid exchanges (SCEs). Clinical features of the disease include proportional dwarfism and a predisposition to develop a wide variety of malignancies. The human BLM gene has been cloned recently and encodes a DNA helicase. Mouse embryos homozygous for a targeted mutation in the murine Bloom's syndrome gene (Blm) are developmentally delayed and die by embryonic day 13.5. The fact that the interrupted gene is the homolog of the human BLM gene was confirmed by its homologous sequence, its chromosomal location, and by demonstrating high numbers of SCEs in cultured murine Blm-/- fibroblasts. The proportional dwarfism seen in the human is consistent with the small size and developmental delay (12-24 hr) seen during mid-gestation in murine Blm-/- embryos. Interestingly, the growth retardation in mutant embryos can be accounted for by a wave of increased apoptosis in the epiblast restricted to early post-implantation embryogenesis. Mutant embryos do not survive past day 13.5, and at this time exhibit severe anemia. Red blood cells and their precursors from Blm-/- embryos are heterogeneous in appearance and have increased numbers of macrocytes and micronuclei. Both the apoptotic wave and the appearance of micronuclei in red blood cells are likely cellular consequences of damaged DNA caused by effects on replicating or segregating chromosomes.

Neoplastic cell transformation by high-LET radiation - Molecular mechanisms

NASA Technical Reports Server (NTRS)

Yang, Tracy Chui-Hsu; Craise, Laurie M.; Tobias, Cornelius A.; Mei, Man-Tong

1989-01-01

Quantitative data were collected on dose-response curves of cultured mouse-embryo cells (C3H10T1/2) irradiated with heavy ions of various charges and energies. Results suggests that two breaks formed on DNA within 80 A may cause cell transformation and that two DNA breaks formed within 20 A may be lethal. From results of experiments with restriction enzymes which produce DNA damages at specific sites, it was found that DNA double strand breaks are important primary lesions for radiogenic cell transformation and that blunt-ended double-strand breaks can form lethal as well as transformational damages due to misrepair or incomplete repair in the cell. The RBE-LET relationship for high-LET radiation is similar to that for HGPRT locus mutation, chromosomal deletion, and cell transformation, indicating that common lesions may be involved in these radiation effects.

Incentives for orphan drug research and development in the United States.

PubMed

Seoane-Vazquez, Enrique; Rodriguez-Monguio, Rosa; Szeinbach, Sheryl L; Visaria, Jay

2008-12-16

The Orphan Drug Act (1983) established several incentives to encourage the development of orphan drugs (ODs) to treat rare diseases and conditions. This study analyzed the characteristics of OD designations, approvals, sponsors, and evaluated the effective patent and market exclusivity life of orphan new molecular entities (NMEs) approved in the US between 1983 and 2007. Primary data sources were the FDA Orange Book, the FDA Office of Orphan Drugs Development, and the US Patent and Trademark Office. Data included all orphan designations and approvals listed by the FDA and all NMEs approved by the FDA during the study period. The FDA listed 1,793 orphan designations and 322 approvals between 1983 and 2007. Cancer was the main group of diseases targeted for orphan approvals. Eighty-three companies concentrated 67.7% of the total orphan NMEs approvals. The average time from orphan designation to FDA approval was 4.0 +/- 3.3 years (mean +/- standard deviation). The average maximum effective patent and market exclusivity life was 11.7 +/- 5.0 years for orphan NME. OD market exclusivity increased the average maximum effective patent and market exclusivity life of ODs by 0.8 years. Public programs, federal regulations, and policies support orphan drugs R&D. Grants, research design support, FDA fee waivers, tax incentives, and orphan drug market exclusivity are the main incentives for orphan drug R&D. Although the 7-year orphan drug market exclusivity provision had a positive yet relatively modest overall effect on effective patent and market exclusivity life, economic incentives and public support mechanisms provide a platform for continued orphan drug development for a highly specialized market.

Incentivizing Orphan Product Development: United States Food and Drug Administration Orphan Incentive Programs.

PubMed

Le, Tran T

2017-01-01

Over 30 years ago, the United States (US) Congress passed the Orphan Drug Act (ODA) to encourage the development of products for rare diseases or conditions ("orphan products"). The Act provided incentives to sponsors for developing products with orphan designation and established a grant program to fund studies of orphan products. Since its enactment in 1983, the ODA has been credited for bringing more than 590 orphan drugs to the market, inspiring the implementation of orphan legislation globally, and enabling the creation of other programs that extend existing knowledge of the natural history of rare diseases and stimulate the development of medical devices for children and patients with rare diseases. This chapter provides a brief overview of the main features and successes of 5 of the orphan incentive programs administered by the US Food and Drug Administration (FDA): the Orphan Drug Designation Program, the Humanitarian Use Device (HUD) Designation Program, the Orphan Products Clinical Trials Grants Program, the Pediatric Device Consortia (PDC) Grant Program, and the Orphan Products Natural History Grants Program.

Outcome of anti-retroviral treatment in HIV-infected orphans and non-orphans at an ART centre in North India.

PubMed

Bhattacharya, Malobika; Saxena, Romit

2012-01-01

Few Indian studies have reported the long-term efficacy of anti-retroviral treatment (ART) in children and in orphaned, HIV-infected children in particular. To study differences in outcome of ART in HIV-infected orphans compared with non-orphans. A retrospective study of 87 HIV-infected children who commenced ART in the period January 2006 to August 2007. The main measures were orphan status, absolute CD4 count and weight-for-height (WHZ) and height-for-age (HAZ) Z-scores. Median follow-up was 33 months. Forty (45·9%) children were orphaned. Orphans and non-orphans had similar baseline median WHZ and HAZ (-2·48 vs -2·63, P = 0·65 and -2·78 vs -2·91, P = 0·77, respectively). The two groups were similar in terms of WHO clinical stage and frequency of severe immunosuppression at presentation (P = 0·88 and 0·25, respectively). After ART initiation, the median absolute CD4 count increased progressively in both groups. Median WHZ and HAZ increased throughout the study period in the orphans and reached -1 at 27 and 39 months of ART, respectively. In the non-orphans, WHZ remained below that of the orphan group, the difference becoming statistically significant from 18 months of ART. The increment in HAZ in the non-orphan group was at par with the orphan group until 12 months of follow-up, after which it fell between 18 and 30 months. Subsequently, HAZ rose but remained below that of the orphan group. Both WHZ and HAZ failed to reach -1 in the non-orphan group. In both groups, 85% reported 100% adherence to ART. The outcome of ART is not affected by orphan status with the extended family adequately supporting orphaned children. Growth of children whose parents are HIV-infected may be constrained despite ART if there is inadequate family support.

The distribution of immunomodulatory cells in the lungs of patients with idiopathic pulmonary fibrosis

PubMed Central

Nuovo, Gerard J.; Hagood, James S.; Magro, Cynthia M.; Chin, Nena; Kapil, Rubina; Davis, Luke; Marsh, Clay B.; Folcik, Virginia A.

2011-01-01

We have characterized the immune system involvement in the disease processes of idiopathic pulmonary fibrosis in novel ways. To do so, we analyzed lung tissue from 21 cases of idiopathic pulmonary fibrosis and 21 (non-fibrotic, non-cancerous) controls for immune cell and inflammation-related markers. The immunohistochemical analysis of the tissue was grouped by patterns of severity in disease pathology. There were significantly greater numbers of CD68+ and CD80+ cells, and significantly fewer CD3+, CD4+, and CD45RO+ cells in areas of relatively (histologically) normal lung in biopsies from idiopathic pulmonary fibrosis patients compared to controls. In zones of active disease, characterized by epithelial cell regeneration and fibrosis, there were significantly more cells expressing CD4, CD8, CD20, CD68, CD80, CCR6, S100, IL-17, tumor necrosis factor-α, and retinoic acid-related orphan receptors compared to histologically normal lung areas from idiopathic pulmonary fibrosis patients. Inflammation was implicated in these active regions by the cells that expressed retinoid orphan receptor-α, -β, and -γ, CCR6, and IL-17. The regenerating epithelial cells predominantly expressed these pro-inflammatory molecules, as evidenced by co-expression analyses with epithelial cytokeratins. Macrophages in pseudo-alveoli and CD3+ T cells in the fibrotic interstitium also expressed IL-17. Co-expression of IL-17 with retinoid orphan receptors, and epithelial cytoskeletal proteins, CD68, and CD3 in epithelial cells, macrophages, and T-cells, respectively, confirmed the production of IL-17 by these cell types. There was little staining for Foxp3, CD56, or CD34 in any idiopathic pulmonary fibrosis lung regions. The fibrotic regions had fewer immune cells overall. In summary, our study shows participation of innate and adaptive mononuclear cells in active-disease regions of idiopathic pulmonary fibrosis lung, where the regenerating epithelial cells appear to propagate inflammation. The regenerative mechanisms become skewed to ultimately result in lethal, fibrotic restriction of lung function. PMID:22037258

The correlation between HTA recommendations and reimbursement status of orphan drugs in Europe.

PubMed

Kawalec, Paweł; Sagan, Anna; Pilc, Andrzej

2016-09-06

The aim of this study was to review and compare types of reimbursement recommendations for orphan drugs issued by eight European health technology assessment (HTA) agencies and the reimbursement status of these drugs in the corresponding countries. Separate calculations were also performed for three sub-groups: ultra-orphan drugs, oncology orphan drugs and other (non-ultra, non-oncology) orphan drugs. We reviewed drugs authorized by the European Medicine Agency (EMA) between 1 November 2002 and 30 September 2015. Among these, we identified 101 orphan drugs. Seventy-nine of them were assessed by eight European HTA agencies. The average rates of positive, conditional and negative reimbursement recommendations issued by these agencies were 55.7 %, 15.3 % and 29.0 %, respectively. On average, 21.2 % of EMA-authorized orphan drugs were reimbursed in the eight European countries studied: 49.0 % of those with positive, 53.6 % of those with conditional, and 16.0 % of those with negative reimbursement recommendations. In addition, 5.4 % of orphan drugs that had not been assessed by any of the eight HTA agencies were also reimbursed. The shares of oncology, ultra, and other orphan drugs that were assessed by HTA agencies were similar, with the lowest share observed in ultra-orphan drugs (72 %) and the highest in other orphan drugs (80 %). In terms of reimbursement, 20 % of oncology orphan drugs, 25 % of ultra-orphan drugs and 21 % of other orphan drugs were reimbursed. Reimbursement of orphan drugs does not always correspond to the type of HTA recommendation. While the highest rate of reimbursement is observed (unsurprisingly) among drugs with positive or conditional recommendation, a high rate of reimbursement (11 %) is also observed among ultra-orphan drugs that had never been assessed by any HTA agency.

Education status among orphans and non-orphans in communities affected by AIDS in Tanzania and Burkina Faso.

PubMed

Kürzinger, M L; Pagnier, J; Kahn, J G; Hampshire, R; Wakabi, T; Dye, T D V

2008-07-01

The AIDS pandemic has created an estimated 15 million orphans who may face elevated risk of poor health and social outcomes. This paper compares orphans and non-orphans regarding educational status and delay using data collected in three low-income communities affected by AIDS in Tanzania and Burkina Faso. Orphans were significantly more likely not to attend school than were non-orphans and also to be delayed when in school, though, after controlling for confounders, the risk was borderline and non-significant. Multivariate analysis indicates that variables such as age, religion, family of origin, the relation between the child and the head of household and the dependency ratio of the household better explain differences in education than does orphan status. This study suggests, therefore, that orphans' educational status is relatively equivalent to non-orphans perhaps as a result of family based or community program safety nets.

Shining a light in the black box of orphan drug pricing

PubMed Central

2014-01-01

Background The pricing mechanism of orphan drugs appears arbitrary and has been referred to as a “black box”. Therefore, the aim of this study is to investigate how drug- and disease-specific variables relate to orphan drug prices. Additionally, we aim to explore if certain country-specific pricing and reimbursement policies affect the price level of orphan drugs. Methods Annual treatment costs per indication per patient were calculated for 59 orphan drugs with a publicly available price in Belgium, the Netherlands, Czech Republic, France, Italy and the United Kingdom. A multiple linear regression model was built with 14 drug- and disease-specific variables. A Mann-Whitney U test was used to explore whether there is a correlation between annual treatment costs of orphan drugs across countries with different pricing and reimbursement policies. Results Repurposed orphan drugs, orally administered orphan drugs or orphan drugs for which an alternative treatment is available are associated with lower annual treatment costs. Orphan drugs with multiple orphan indications, for chronic treatments or for which an improvement in overall survival or quality-of-life has been demonstrated, are associated with higher annual treatment costs. No association was found between annual treatments cost of orphan drugs across countries and the different pricing and reimbursement systems. Conclusions This study has shown that prices of orphan drugs are influenced by factors such as the availability of an alternative drug treatment, repurposing, etc. Current debate about the affordability of orphan drugs highlights the need for more transparency in orphan drug price setting. PMID:24767472

EU orphan regulation--ten years of application.

PubMed

Michaux, Geneviève

2010-01-01

In April 2000, European Regulation (EC) No 141/2000 on Orphan Medicinal Products, which, following the U.S. example, had been adopted to boost the research, development, and marketing of medicinal products for rare diseases, became effective. Ten years later, figures prove that, with an average of more than 70 orphan designations per year, the European orphan regulation is a success. To date, the key issue is no longer research and development but effective market access. Less than 10% of the orphan designated products are approved for marketing and even less products are actually placed on the European national markets due to pricing and reimbursement obstacles. The article examines the European orphan regime, focusing on its two cornerstones--orphan designation and exclusivity--and highlighting the concepts that are still unclear and the issues that have not yet been addressed. The European Orphan Regulation has been proved to work well, but it would be even more successful if orphan designation was easier and orphan incentives were more attractive. The article concludes on the changes to be made to the European orphan legal regime that would encourage even more the research and development of orphan products.

Increased expression of Hsp70 and Hsp90 mRNA as biomarkers of thermal stress in loggerhead turtle embryos (Caretta Caretta).

PubMed

Tedeschi, J N; Kennington, W J; Berry, O; Whiting, S; Meekan, M; Mitchell, N J

2015-01-01

The survival and viability of sea turtle embryos is dependent upon favourable nest temperatures throughout the incubation period. Consequently, future generations of sea turtles may be at risk from increasing nest temperatures due to climate change, but little is known about how embryos respond to heat stress. Heat shock genes are likely to be important in this process because they code for proteins that prevent cellular damage in response to environmental stressors. This study provides the first evidence of an expression response in the heat shock genes of embryos of loggerhead sea turtles (Caretta caretta) exposed to realistic and near-lethal temperatures (34°C and 36°C) for 1 or 3 hours. We investigated changes in Heat shock protein 60 (Hsp60), Hsp70, and Hsp90 mRNA in heart (n=24) and brain tissue (n=29) in response to heat stress. Under the most extreme treatment (36°C, 3h), Hsp70 increased mRNA expression by a factor of 38.8 in heart tissue and 15.7 in brain tissue, while Hsp90 mRNA expression increased by a factor of 98.3 in heart tissue and 14.7 in brain tissue. Hence, both Hsp70 and Hsp90 are useful biomarkers for assessing heat stress in the late-stage embryos of sea turtles. The method we developed can be used as a platform for future studies on variation in the thermotolerance response from the clutch to population scale, and can help us anticipate the resilience of reptile embryos to extreme heating events. Copyright © 2014 Elsevier Ltd. All rights reserved.

CuInS2/ZnS QD exposure induces developmental toxicity, oxidative stress and DNA damage in rare minnow (Gobiocypris rarus) embryos and larvae.

PubMed

Liu, Li; Xiao, Yuan-Yuan; Ji, Yan-Hong; Liu, Ming-Zhi; Chen, Yao; Zeng, Yu-Lian; Zhang, Yao-Guang; Jin, Li

2017-08-01

Chinese rare minnow (Gobiocypris rarus) embryos were used as an experimental model to investigate the effects of CuInS 2 /ZnS quantum dots (QDs) on the early life stages of G. rarus. Normal developmental parameters (survival rate, body length and average heart rate), biomarker genes [stress response (Hsp70), detoxification (Cyp1a), organizer function and axis formation (Wnt8α), and muscle (Mstn)], enzymatic activity and DNA damage were recorded as endpoints in the developing embryos/larvae after exposure until 96h post-fertilization (hpf). Reduced survival rate, decreased heart rate, altered body length, increased malformation rate, decreased hatching rate, advanced hatching time in response to low concentrations (50 and 100nmol/L) and delayed hatching time in response to high concentrations were observed after exposure, as were many other toxic effects, including pericardial edema and bent tails. The 72 hpf LC 50 (median lethal concentration) was determined to be 624.364nmol/L. Treatment with certain concentrations of CuInS 2 /ZnS QDs significantly increased the superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels and significantly induced DNA damage. After treatment with CuInS 2 /ZnS QDs, the embryos showed highly up-regulated expression of Hsp70, Cyp1a and Wnt8a and significantly up-regulated expression of Mstn at 12 hpf. Overall, this study indicates that CuInS 2 /ZnS QDs are potentially toxic to G. rarus embryos. The information presented in this study will be helpful for fully understanding the toxicity induced by CuInS 2 /ZnS QDs in fish embryos. Copyright © 2017 Elsevier Inc. All rights reserved.

The Expression of TALEN before Fertilization Provides a Rapid Knock-Out Phenotype in Xenopus laevis Founder Embryos.

PubMed

Miyamoto, Kei; Suzuki, Ken-Ichi T; Suzuki, Miyuki; Sakane, Yuto; Sakuma, Tetsushi; Herberg, Sarah; Simeone, Angela; Simpson, David; Jullien, Jerome; Yamamoto, Takashi; Gurdon, J B

2015-01-01

Recent advances in genome editing using programmable nucleases have revolutionized gene targeting in various organisms. Successful gene knock-out has been shown in Xenopus, a widely used model organism, although a system enabling less mosaic knock-out in founder embryos (F0) needs to be explored in order to judge phenotypes in the F0 generation. Here, we injected modified highly active transcription activator-like effector nuclease (TALEN) mRNA to oocytes at the germinal vesicle (GV) stage, followed by in vitro maturation and intracytoplasmic sperm injection, to achieve a full knock-out in F0 embryos. Unlike conventional injection methods to fertilized embryos, the injection of TALEN mRNA into GV oocytes allows expression of nucleases before fertilization, enabling them to work from an earlier stage. Using this procedure, most of developed embryos showed full knock-out phenotypes of the pigmentation gene tyrosinase and/or embryonic lethal gene pax6 in the founder generation. In addition, our method permitted a large 1 kb deletion. Thus, we describe nearly complete gene knock-out phenotypes in Xenopus laevis F0 embryos. The presented method will help to accelerate the production of knock-out frogs since we can bypass an extra generation of about 1 year in Xenopus laevis. Meantime, our method provides a unique opportunity to rapidly test the developmental effects of disrupting those genes that do not permit growth to an adult able to reproduce. In addition, the protocol shown here is considerably less invasive than the previously used host transfer since our protocol does not require surgery. The experimental scheme presented is potentially applicable to other organisms such as mammals and fish to resolve common issues of mosaicism in founders.

The use of the zebrafish (Danio rerio) embryo for the acute toxicity testing of surfactants, as a possible alternative to the acute fish test.

PubMed

Vaughan, Martin; van Egmond, Roger

2010-06-01

At present, the acute toxicity of chemicals to fish is most commonly estimated by means of a short-term test on juvenile or adult animals (OECD TG 203). Although, over the last few years, the numbers used have been reduced due to the implementation of the Three Rs (Reduction, Refinement and Replacement), significant numbers of fish are still used in acute toxicity tests. With the introduction of the new European Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) system, this number is likely to increase dramatically. The aim of this work was to test the acute toxicity of a number of anionic, cationic and non-ionic surfactants to embryos of the zebrafish (Danio rerio), over 48 hours, as a possible alternative to the standard 96-hour fish acute test. We measured the toxicities of 15 surfactants, and compared the results to previously generated adult D. rerio LC50 data (or other fish species, if these data were not available). Comparison of the LC50 data showed that embryos appear to be as sensitive to cationic and non-ionic surfactants as the adult fish, but possibly are more sensitive to anionic surfactants. Toxicity testing with the embryo test can be carried out more quickly than with the adult test, uses much less space and media, requires less effort, and therefore can be performed at a reduced cost. The embryo test may also uncover additional sub-lethal effects, although these were not observed for surfactants. The data presented here show that the 48-hour embryo test can be considered as a suitable alternative to the adult acute fish test for surfactants.

No turning, a mouse mutation causing left-right and axial patterning defects.

PubMed

Melloy, P G; Ewart, J L; Cohen, M F; Desmond, M E; Kuehn, M R; Lo, C W

1998-01-01

Patterning along the left/right axes helps establish the orientation of visceral organ asymmetries, a process which is of fundamental importance to the viability of an organism. A linkage between left/right and axial patterning is indicated by the finding that a number of genes involved in left/right patterning also play a role in anteroposterior and dorsoventral patterning. We have recovered a spontaneous mouse mutation causing left/right patterning defects together with defects in anteroposterior and dorsoventral patterning. This mutation is recessive lethal and was named no turning (nt) because the mutant embryos fail to undergo embryonic turning. nt embryos exhibit cranial neural tube closure defects and malformed somites and are caudally truncated. Development of the heart arrests at the looped heart tube stage, with cardiovascular defects indicated by ballooning of the pericardial sac and the pooling of blood in various regions of the embryo. Interestingly, in nt embryos, the direction of heart looping was randomized. Nodal and lefty, two genes that are normally expressed only in the left lateral plate mesoderm, show expression in the right and left lateral plate mesoderm. Lefty, which is normally also expressed in the floorplate, is not found in the prospective floor plate of nt embryos. This suggests the possibility of notochordal defects. This was confirmed by histological analysis and the examination of sonic hedgehog, Brachyury, and HNF-3 beta gene expression. These studies showed that the notochord is present in the early nt embryo, but degenerates as development progresses. Overall, these findings support the hypothesis that the notochord plays an active role in left/right patterning. Our results suggest that nt may participate in this process by modulating the notochordal expression of HNF-3 beta.

Uneven drying of zygotic embryos and embryonic axes of recalcitrant seeds: challenges and considerations for cryopreservation.

PubMed

Ballesteros, Daniel; Sershen; Varghese, Boby; Berjak, Patricia; Pammenter, Norman W

2014-08-01

Cryopreservation is the most promising option for the long-term germplasm conservation of recalcitrant-seeded species. However, the variable post-cryo success achieved with the excised zygotic explants traditionally used for cryopreservation has been a concern for some time. Differential drying rates amongst explants of different species, uneven drying amongst explants within a batch of seeds and uneven drying across tissues within individual embryos could be contributory factors to this variable success and these phenomena form the foci of the present study. Using zygotic explants from a range of recalcitrant-seeded species, which included sub-tropical dicotyledonous trees and sub-tropical monocotyledonous geophytes, the study showed that embryo morphology and anatomy are critical determinants of the drying characteristics of the different tissues composing the explant and hence, post-cryo survival. The results suggest that the rates of drying of explants to water contents (WCs) in the theoretically optimal range for successful cryopreservation are species-specific, and that more rapid drying rates may promote post-cryo survival. However, the large variation in WC amongst individual explants in bulk samples challenges the selection of the theoretically optimum WC for cryopreservation. As a consequence of differential drying rates across the different tissues composing explants, either lethal ice crystal damage or desiccation damage may sometimes be likely in tissues responsible for the onwards development of the embryo. Drying times for cryopreservation of such explants should, therefore, be selected on the basis of WC of segments containing root or shoot meristem, rather than embryo bulk WC. Drying intensity and duration also interact with explant morphology and embryo/axis size and anatomy to bring about - or preclude - post-cryo survival. Copyright © 2014 Elsevier Inc. All rights reserved.

Neglect and perceived stigmatization impact psychological distress of orphans in Tanzania.

PubMed

Hermenau, Katharin; Eggert, Ina; Landolt, Markus A; Hecker, Tobias

2015-01-01

Research has shown that orphans in sub-Saharan Africa are at increased risk for mental health problems. Exposure to maltreatment and HIV/AIDS-related stigmatization are related to orphans' psychological distress. Yet, researchers stress the need for more research in low-income countries to identify which factors of being an orphan may lead to psychological distress. The present study aims to systematically investigate orphans' experiences of maltreatment and stigmatization to identify factors that relate to their psychological distress. In total, 89 Tanzanian children who had lost at least one parent were compared to 89 matched non-orphans (mean age: 11 years; 51% boys). We measured exposure to maltreatment and perceived stigmatization as an orphan. Mental health was assessed using the Strengths and Difficulties Questionnaire, the Children's Depression Inventory, the UCLA PTSD Index for Children, and the Reactive-Proactive Questionnaire. Orphans reported significantly more experiences of neglect, but not of abuse. A group comparison revealed more depressive symptoms, posttraumatic stress symptoms, and aggressive behavior among orphans. Neglect, abuse, and stigmatization correlated with orphans' internalizing and externalizing problems, yet only neglect and stigmatization were related to orphans' depression severity. Perceived stigmatization moderated the relationship between neglect and depression. Our findings suggest that orphans in Tanzania are at increased risk of experiencing neglect. Maltreatment and perceived stigmatization may play a role in orphans' psychological distress. Culturally appropriate and evidence-based interventions may help to prevent maltreatment and stigmatization of orphans.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muecke, J.; Happle, R.; Theile, H.

Although it is true that MIDAS syndrome, Aicardi syndrome and Goltz syndrome show the same transmission, representing X-linked dominant traits with lethality of hemizygote male embryos, and have a number of anomalies such as defects of the eyes or brain in common, it should be noted that MIDAS syndrome and Goltz syndrome have so far never occurred as alternating phenotypes within the same family. In addition, the observation of MIDAS syndrome in a mother and her daughter lends additional support to the notion that this syndrome represents a distinct entity. 3 refs., 4 figs.

Depression among AIDS-orphaned children higher than among other orphaned children in southern India

PubMed Central

2014-01-01

Background Systematic data on mental health issues among orphaned children are not readily available in India. This study explored depression and its associated risk factors among orphaned children in Hyderabad city in south India. Methods 400 orphaned children drawn equally from AIDS and non-AIDS orphan groups aged 12–16 years residing in orphanages in and around Hyderabad city in southern India were recruited to assess depression and associated risk factors using the Center for Epidemiologic Studies-Depression Scale (CES-DC). Variation in the intensity of depression was assessed using multiple classification analysis (MCA). Results 397 (99%) orphans provided complete interviews in the study of whom 306 (76.5%) were aged 12 to 14 years, and 206 (51.8%) were paternal orphans. Children orphaned by AIDS were significantly more likely to report being bullied by friends or relatives (50.3%) and report experiencing discrimination (12.6%) than those orphaned due to other reasons (p < 0.001). The overall prevalence of depression score >15 with CES-DC was 74.1% (95% CI 69.7-78.4) with this being significantly higher for children orphaned by AIDS (84.4%, 95% CI 79.4 – 89.5) than those due to other reasons (63.6%, 95% CI 56.9 – 70.4). Mean depression score was significantly higher for children orphaned by AIDS (34.6) than the other group (20.6; p < 0.001). Among the children orphaned by AIDS, the bulk of depression score was clustered in 12–14 years age groups whereas in the children orphaned by other reasons it was clustered in the 15–16 years age group (p = 0.001). MCA analysis showed being a child orphaned by AIDS had the highest effect on the intensity of depression (Beta = 0.473). Conclusions Children orphaned by AIDS had significantly higher depressive symptoms than the other orphaned children. These findings could be used for further planning of mental health interventions to meet the mental health needs of orphaned children, that could include preventive, diagnostic and treatment services. PMID:24708649

SOCIAL SUPPORT DISPARITIES FOR CAREGIVERS OF AIDS-ORPHANED CHILDREN IN SOUTH AFRICA

PubMed Central

Kuo, Caroline; Fitzgerald, Jane; Operario, Don; Casale, Marisa

2012-01-01

Drawing upon a sample of 1,599 adults caring for children in HIV-endemic Umlazi Township in South Africa, this cross-sectional survey investigated whether perceived social support varied among caregivers of AIDS-orphaned children (n=359) as compared to caregivers of children orphaned by other causes (n=171) and caregivers of non-orphaned children (n=1,069). Results of multivariate linear regressions indicate that caregivers of AIDS-orphaned children reported significantly lower levels of social support compared to caregivers of other-orphaned children and non-orphaned children independent of socio-demographic covariates. Caregivers of other-orphaned and non-orphaned children reported similar levels of social support. In terms of sources of support, all caregivers were more likely to draw support from family and significant others rather than friends. These findings indicate a need to develop interventions that can increase levels of social support for caregivers of AIDS-orphaned children, particularly networks that include friends and significant others. PMID:22904575

Estimating the budget impact of orphan medicines in Europe: 2010 - 2020.

PubMed

Schey, Carina; Milanova, Tsveta; Hutchings, Adam

2011-09-27

Orphan drugs are a growing issue of importance to European healthcare policy makers. The success of orphan drug legislation in Europe has resulted in an increasing number of licensed medicines for rare diseases, and many more yet unlicensed products have received orphan drug designation. Increasingly the concerns amongst policy makers relate to issues of patient access and affordability, yet few studies have sought to estimate the future budget impact of orphan drugs. The aim of this study was to predict the total cost of orphan medicines in Europe between 2010 and 2020 as a percentage of total European pharmaceutical expenditure. A disease-based epidemiological model was created based upon trends in the designation and approval of new orphan medicines, prevalence estimates for orphan diseases, and historical price and sales data for orphan drugs in Europe (defined as Eurozone + UK). The analysis incorporated two stages: 1) Predicting the number of diseases for which new orphan drugs will be approved over the next decade, based on an analysis of trends from the EU registry of orphan medicines; 2) Estimating the average ex-factory drug cost across an orphan disease life cycle, from the year in which the first orphan medicine is launched to the point where the first medicine loses marketing exclusivity. The two sets of information were combined to quantify the annual cost of orphan drugs from 2010 through 2020. The results from the model predicted a steady increase in the cumulative number of diseases for which an orphan drug is approved, averaging just over 5 new diseases per year over the next 10 years. The annual per patient cost of existing orphan drugs was seen to vary between €1,251 and €407,631, with the median cost being €32,242 per year. The share of the total pharmaceutical market represented by orphan drugs is predicted to increase from 3.3% in 2010 to a peak of 4.6% in 2016 after which it is expected to level off through 2020, as growth falls into line with that in the wider pharmaceutical market. In sensitivity analysis peak-year orphan drug budget impact ranged between 3% - 6.6%. Although European orphan drug legislation has led to an increase in the number of approved orphan drugs, the growth in cost, as a proportion of total pharmaceutical expenditure, is likely to plateau over the next decade as orphan growth rates converge on those in the broader pharmaceutical market. Given the assumptions and simplifications inherent in such a projection, there is uncertainty around the base case forecast and further research is needed to monitor how trends develop. However, fears that growth in orphan drug expenditure will lead to unsustainable cost escalation do not appear to be justified. Furthermore, based on the results of this budget impact forecast, the European orphan drug legislation is not leading to a disproportionate impact on pharmaceutical expenditure.

Estimating the budget impact of orphan medicines in Europe: 2010 - 2020

PubMed Central

2011-01-01

Background Orphan drugs are a growing issue of importance to European healthcare policy makers. The success of orphan drug legislation in Europe has resulted in an increasing number of licensed medicines for rare diseases, and many more yet unlicensed products have received orphan drug designation. Increasingly the concerns amongst policy makers relate to issues of patient access and affordability, yet few studies have sought to estimate the future budget impact of orphan drugs. The aim of this study was to predict the total cost of orphan medicines in Europe between 2010 and 2020 as a percentage of total European pharmaceutical expenditure. Methods A disease-based epidemiological model was created based upon trends in the designation and approval of new orphan medicines, prevalence estimates for orphan diseases, and historical price and sales data for orphan drugs in Europe (defined as Eurozone + UK). The analysis incorporated two stages: 1) Predicting the number of diseases for which new orphan drugs will be approved over the next decade, based on an analysis of trends from the EU registry of orphan medicines; 2) Estimating the average ex-factory drug cost across an orphan disease life cycle, from the year in which the first orphan medicine is launched to the point where the first medicine loses marketing exclusivity. The two sets of information were combined to quantify the annual cost of orphan drugs from 2010 through 2020. Results The results from the model predicted a steady increase in the cumulative number of diseases for which an orphan drug is approved, averaging just over 5 new diseases per year over the next 10 years. The annual per patient cost of existing orphan drugs was seen to vary between €1,251 and €407,631, with the median cost being €32,242 per year. The share of the total pharmaceutical market represented by orphan drugs is predicted to increase from 3.3% in 2010 to a peak of 4.6% in 2016 after which it is expected to level off through 2020, as growth falls into line with that in the wider pharmaceutical market. In sensitivity analysis peak-year orphan drug budget impact ranged between 3% - 6.6%. Conclusions Although European orphan drug legislation has led to an increase in the number of approved orphan drugs, the growth in cost, as a proportion of total pharmaceutical expenditure, is likely to plateau over the next decade as orphan growth rates converge on those in the broader pharmaceutical market. Given the assumptions and simplifications inherent in such a projection, there is uncertainty around the base case forecast and further research is needed to monitor how trends develop. However, fears that growth in orphan drug expenditure will lead to unsustainable cost escalation do not appear to be justified. Furthermore, based on the results of this budget impact forecast, the European orphan drug legislation is not leading to a disproportionate impact on pharmaceutical expenditure. PMID:21951518

Orphan care in Botswana's working households: growing responsibilities in the absence of adequate support.

PubMed

Miller, Candace M; Gruskin, Sofia; Subramanian, S V; Rajaraman, Divya; Heymann, S Jody

2006-08-01

Botswana has one of the world's highest HIV-prevalence rates and the world's highest percentages of orphaned children among its population. We assessed the ability of income-earning households in Botswana to adequately care for orphans. We used data from the Botswana Family Health Needs Study (2002), a sample of 1033 working adults with caregiving responsibilities who used public services, to assess whether households with orphan-care responsibilities encountered financial and other difficulties. Thirty-seven percent of respondents provided orphan care, usually to extended family members. We applied logistic regression models to determine the factors associated with experiencing problems related to orphan caregiving. Nearly half of working households with orphan-care responsibilities reported experiencing financial and other difficulties because of orphan care. Issues of concern included caring for multiple orphans, caring for sick adults and orphans simultaneously, receiving no assistance, and low income. The orphan crisis is impoverishing even working households, where caregivers lack sufficient resources to provide basic needs. Neither the public sector nor communities provide adequate safety nets. International assistance is critical to build capacity within the social welfare infrastructure and to fund community-level activities that support households. Lessons from Botswana's orphan crisis can provide valuable insights to policymakers throughout sub-Saharan Africa.

Depression amongst carers of AIDS-orphaned and other-orphaned children in Umlazi Township, South Africa

PubMed Central

Kuo, Caroline; Operario, Don; Cluver, Lucie

2011-01-01

South Africa faces the challenge of supporting the well-being of adults caring for growing numbers of AIDS-orphaned children. These adults play a critical role in responses to the epidemic but little information exists in regards to their mental health needs. This paper reports on findings from n=1599 adults, recruited through representative household sampling, who serve as primary carers for children in Umlazi Township, a HIV endemic community. Overall, 22% of participants were carers of AIDS-orphaned children, 11% were carers of other-orphaned children, and 67% were carers of non-orphaned children. Prevalence of depression was 30.3%. Orphan carers, regardless of whether they cared for AIDS-orphaned and other-orphaned children, were significantly more likely than carers of non-orphaned children to meet the clinical threshold for depression (35.2% versus 27.9%, p<.01). In multivariate logistic regressions, food insecurity and being a female carer were identified as additional risk factors for greater depression. In contrast, households with access to running water and households dependent on salaries as the main source of income were identified as protective factors for disparities in depression. Mental health interventions are urgently needed to address an increased risk for depression amongst all orphan carers, not just those caring for AIDS-orphaned children. PMID:22081931

Access to Orphan Drugs: A Comprehensive Review of Legislations, Regulations and Policies in 35 Countries.

PubMed

Gammie, Todd; Lu, Christine Y; Babar, Zaheer Ud-Din

2015-01-01

To review existing regulations and policies utilised by countries to enable patient access to orphan drugs. A review of the literature (1998 to 2014) was performed to identify relevant, peer-reviewed articles. Using content analysis, we synthesised regulations and policies for access to orphan drugs by type and by country. Fifty seven articles and 35 countries were included in this review. Six broad categories of regulation and policy instruments were identified: national orphan drug policies, orphan drug designation, marketing authorization, incentives, marketing exclusivity, and pricing and reimbursement. The availability of orphan drugs depends on individual country's legislation and regulations including national orphan drug policies, orphan drug designation, marketing authorization, marketing exclusivity and incentives such as tax credits to ensure research, development and marketing. The majority of countries (27/35) had in place orphan drug legislation. Access to orphan drugs depends on individual country's pricing and reimbursement policies, which varied widely between countries. High prices and insufficient evidence often limit orphan drugs from meeting the traditional health technology assessment criteria, especially cost-effectiveness, which may influence access. Overall many countries have implemented a combination of legislations, regulations and policies for orphan drugs in the last two decades. While these may enable the availability and access to orphan drugs, there are critical differences between countries in terms of range and types of legislations, regulations and policies implemented. Importantly, China and India, two of the largest countries by population size, both lack national legislation for orphan medicines and rare diseases, which could have substantial negative impacts on their patient populations with rare diseases.

Caregivers' and non-caregivers' knowledge regarding HIV/AIDS and attitude towards HIV/AIDS and orphans in Nigeria.

PubMed

Ohnishi, Mayumi; Nakamura, Keiko; Kizuki, Masashi; Seino, Kaoruko; Inose, Tomoko; Takano, Takehito

2008-09-01

Nigeria has an estimated 930,000 AIDS orphans, which has a marked impact on family and community. This study was performed to characterise caregivers' knowledge regarding HIV/AIDS and their attitude towards HIV/AIDS, orphans in general and AIDS orphans in particular. Caregivers and non-caregivers aged 25-70 years in Nigeria were interviewed from January and March 2003, and logistic regression analysis was used to determine associations between caregivers' knowledge regarding HIV/AIDS and attitudes towards HIV/AIDS, orphans and AIDS orphans, and demographic characteristics and background status regarding HIV/AIDS and orphans. A total of 824 interviewees participated in the survey (82.4% response rate), of whom 290 (35.2%) were current caregivers of orphans. The mean number of orphans per current caregiver was 1.8 (standard deviation 1.4). Factors related to higher knowledge level regarding HIV/AIDS were female gender [odds ratio (OR) = 3.49; 95% confidence interval (CI): 2.33, 5.22] and belief that AIDS is a common disease (OR = 3.39; 95% CI: 2.19, 5.26). Factors associated with positive attitudes towards HIV/AIDS, orphans in general and AIDS orphans in particular were age 35-44 years (OR = 1.73; 95% CI: 1.11, 2.69), Koranic schooling (OR = 8.69; 95% CI: 2.42, 31.19), polygamy (OR = 1.76; 95% CI: 1.17, 2.62), belief that there are increasing numbers of orphans in the community (OR = 2.59; 95% CI: 1.32, 5.08) and having relatives or friends with HIV/AIDS (OR = 2.88; 95% CI: 1.61, 1.58). There was a slight correlation (r = 0.17, P < 0.001) between caregivers' knowledge regarding HIV/AIDS and positive attitudes towards HIV/AIDS, orphans and AIDS orphans. Demographic characteristics and personal experience should be taken into consideration to improve attitudes and behaviour related to HIV/AIDS and caring for orphans and AIDS orphans.

Maternal provision of transformer-2 is required for female development and embryo viability in the wasp Nasonia vitripennis.

PubMed

Geuverink, Elzemiek; Rensink, Anna H; Rondeel, Inge; Beukeboom, Leo W; van de Zande, Louis; Verhulst, Eveline C

2017-11-01

In insect sex determination a primary signal starts the genetic sex determination cascade that, in most insect orders, is subsequently transduced down the cascade by a transformer (tra) ortholog. Only a female-specifically spliced tra mRNA yields a functional TRA-protein that forms a complex with TRA2, encoded by a transformer-2 (tra2) ortholog, to act as a sex specific splicing regulator of the downstream transcription factors doublesex (dsx) and fruitless (fru). Here, we identify the tra2 ortholog of the haplodiploid parasitoid wasp N. vitripennis (Nv-tra2) and confirm its function in N. vitripennis sex determination. Knock down of Nv-tra2 by parental RNA interference (pRNAi) results in complete sex reversal of diploid offspring from female to male, indicating the requirement of Nv-tra2 for female sex determination. As Nv-tra2 pRNAi leads to frequent lethality in early developmental stages, maternal provision of Nv-tra2 transcripts is apparently also required for another, non-sex determining function during embryogenesis. In addition, lethality following Nv-tra2 pRNAi appears more pronounced in diploid than in haploid offspring. This diploid lethal effect was also observed following Nv-tra pRNAi, which served as a positive control in our experiments. As diploid embryos from fertilized eggs have a paternal chromosome set in addition to the maternal one, this suggests that either the presence of this paternal chromosome set or the dosage effect resulting from the diploid state is incompatible with the induced male development in N. vitripennis caused by either Nv-tra2 or Nv-tra pRNAi. The role of Nv-tra2 in activating the female sex determination pathway yields more insight into the sex determination mechanism of Nasonia. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Mutations at the flavin binding site of ETF:QO yield a MADD-like severe phenotype in Drosophila.

PubMed

Alves, Ema; Henriques, Bárbara J; Rodrigues, João V; Prudêncio, Pedro; Rocha, Hugo; Vilarinho, Laura; Martinho, Rui G; Gomes, Cláudio M

2012-08-01

Following a screening on EMS-induced Drosophila mutants defective for formation and morphogenesis of epithelial cells, we have identified three lethal mutants defective for the production of embryonic cuticle. The mutants are allelic to the CG12140 gene, the fly homologue of electron transfer flavoprotein:ubiquinone oxidoreductase (ETF:QO). In humans, inherited defects in this inner membrane protein account for multiple acyl-CoA dehydrogenase deficiency (MADD), a metabolic disease of β-oxidation, with a broad range of clinical phenotypes, varying from embryonic lethal to mild forms. The three mutant alleles carried distinct missense mutations in ETF:QO (G65E, A68V and S104F) and maternal mutant embryos for ETF:QO showed lethal morphogenetic defects and a significant induction of apoptosis following germ-band elongation. This phenotype is accompanied by an embryonic accumulation of short- and medium-chain acylcarnitines (C4, C8 and C12) as well as long-chain acylcarnitines (C14 and C16:1), whose elevation is also found in severe MADD forms in humans under intense metabolic decompensation. In agreement the ETF:QO activity in the mutant embryos is markedly decreased in relation to wild type activity. Amino acid sequence analysis and structural mapping into a molecular model of ETF:QO show that all mutations map at FAD interacting residues, two of which at the nucleotide-binding Rossmann fold. This structural domain is composed by a β-strand connected by a short loop to an α-helix, and its perturbation results in impaired cofactor association via structural destabilisation and consequently enzymatic inactivation. This work thus pinpoints the molecular origins of a severe MADD-like phenotype in the fruit fly and establishes the proof of concept concerning the suitability of this organism as a potential model organism for MADD. © 2012 Elsevier B.V. All rights reserved.

Acute and chronic toxicity of nickel to rainbow trout (Oncorhynchus mykiss).

PubMed

Brix, Kevin V; Keithly, James; DeForest, David K; Laughlin, Jim

2004-09-01

Of the fish species tested in chronic Ni exposures, rainbow trout (Oncorhynchus mykiss) is the most sensitive. To develop additional Ni toxicity data and to investigate the toxic mode of action for Ni, we conducted acute (96-h) and chronic (85-d early life-stage) flow-through studies using rainbow trout. In addition to standard toxicological endpoints, we investigated the effects of Ni on ionoregulatory physiology (Na, Ca, and Mg). The acute median lethal concentration for Ni was 20.8 mg/L, and the 24-h gill median lethal accumulation was 666 nmol/g wet weight. No effects on plasma Ca, Mg, or Na were observed during acute exposure. In the chronic study, no significant effects on embryo survival, swim-up, hatching, or fingerling survival or growth were observed at dissolved Ni concentrations up to 466 microg/L, the highest concentration tested. This concentration is considerably higher than the only other reported chronic no-observed-effect concentration (<33 microg/L) for rainbow trout. Accumulation of Ni in trout eggs indicates the chorion is only a partial barrier with 36%, 63%, and 1% of total accumulated Ni associated with the chorion, yolk, and embryo, respectively. Whole-egg ion concentrations were reduced by Ni exposure. However, most of this reduction occurred in the chorion rather than in the embryos, and no effects on hatching success or larval survival were observed as a result. Plasma ion concentrations measured in swim-up fingerlings at the end of the chronic-exposure period were not significantly reduced by exposure to Ni. Nickel accumulated on the gill in an exponential manner but plateaued in trout plasma at waterborne Ni concentrations of 118 microg/L or greater. Consistent with previous studies, Ni did not appear to disrupt ionoregulation in acute exposures of rainbow trout. Our results also suggest that Ni is not an ionoregulatory toxicant in long-term exposures, but the lack of effects in the highest Ni treatment precludes a definitive conclusion.

Tuning of RNA editing by ADAR is required in Drosophila

PubMed Central

Keegan, Liam P; Brindle, James; Gallo, Angela; Leroy, Anne; Reenan, Robert A; O'Connell, Mary A

2005-01-01

RNA editing increases during development in more than 20 transcripts encoding proteins involved in rapid synaptic neurotransmission in Drosophila central nervous system and muscle. Adar (adenosine deaminase acting on RNA) mutant flies expressing only genome-encoded, unedited isoforms of ion-channel subunits are viable but show severe locomotion defects. The Adar transcript itself is edited in adult wild-type flies to generate an isoform with a serine to glycine substitution close to the ADAR active site. We show that editing restricts ADAR function since the edited isoform of ADAR is less active in vitro and in vivo than the genome-encoded, unedited isoform. Ubiquitous expression in embryos and larvae of an Adar transcript that is resistant to editing is lethal. Expression of this transcript in embryonic muscle is also lethal, with above-normal, adult-like levels of editing at sites in a transcript encoding a muscle voltage-gated calcium channel. PMID:15920480

Nodal patterning without Lefty inhibitory feedback is functional but fragile

PubMed Central

Gagnon, James A; Pauli, Andrea; Zimmerman, Steven; Aksel, Deniz C; Reyon, Deepak; Tsai, Shengdar Q; Joung, J Keith

2017-01-01

Developmental signaling pathways often activate their own inhibitors. Such inhibitory feedback has been suggested to restrict the spatial and temporal extent of signaling or mitigate signaling fluctuations, but these models are difficult to rigorously test. Here, we determine whether the ability of the mesendoderm inducer Nodal to activate its inhibitor Lefty is required for development. We find that zebrafish lefty mutants exhibit excess Nodal signaling and increased specification of mesendoderm, resulting in embryonic lethality. Strikingly, development can be fully restored without feedback: Lethal patterning defects in lefty mutants can be rescued by ectopic expression of lefty far from its normal expression domain or by spatially and temporally uniform exposure to a Nodal inhibitor drug. While drug-treated mutants are less tolerant of mild perturbations to Nodal signaling levels than wild type embryos, they can develop into healthy adults. These results indicate that patterning without inhibitory feedback is functional but fragile. PMID:29215332

Trimethyltin chloride inhibits neuronal cell differentiation in zebrafish embryo neurodevelopment.

PubMed

Kim, Jin; Kim, C-Yoon; Song, Juha; Oh, Hanseul; Kim, Cheol-Hee; Park, Jae-Hak

2016-01-01

Trimethyltin chloride (TMT) is a neurotoxicant widely present in the aquatic environment, primarily from effluents of the plastic industry. It is known to cause acute neuronal death in the limbic-cerebellar system, particularly in the hippocampus. However, relatively few studies have estimated the effects of TMT toxicity on neurodevelopment. In this study, we confirmed the dose-dependent effects of TMT on neurodevelopmental stages through analysis of morphological changes and fluorescence assays using HuC-GFP and olig2-dsRed transgenic zebrafish embryos. In addition, we analyzed the expression of genes and proteins related to neurodevelopment. Exposure of embryos to TMT for 4 days post fertilization (dpf) elicited a concentration-related decrease in body length and increase in axial malformation. TMT affected the fluorescent CNS structure by decreasing pattern of HuC-GFP and olig2-dsRed transgenic zebrafish. In addition, it significantly modulated the expression patterns of Sonic hedgehog a (Shha), Neurogenin1 (Ngn1), Embryonic lethal abnormal vision like protein 3 (Elavl3), and Glial fibrillary acidic protein (Gfap). The overexpression of Shha and Ngn1, and downregulation of Elavl3 and Gfap, indicate repression of proneural cell differentiation. Our study demonstrates that TMT inhibits specific neurodevelopmental stages in zebrafish embryos and suggests a possible mechanism for the toxicity of TMT in vertebrate neurodevelopment. Copyright © 2015 Elsevier Inc. All rights reserved.

OECD validation study to assess intra- and inter-laboratory reproducibility of the zebrafish embryo toxicity test for acute aquatic toxicity testing.

PubMed

Busquet, François; Strecker, Ruben; Rawlings, Jane M; Belanger, Scott E; Braunbeck, Thomas; Carr, Gregory J; Cenijn, Peter; Fochtman, Przemyslaw; Gourmelon, Anne; Hübler, Nicole; Kleensang, André; Knöbel, Melanie; Kussatz, Carola; Legler, Juliette; Lillicrap, Adam; Martínez-Jerónimo, Fernando; Polleichtner, Christian; Rzodeczko, Helena; Salinas, Edward; Schneider, Katharina E; Scholz, Stefan; van den Brandhof, Evert-Jan; van der Ven, Leo T M; Walter-Rohde, Susanne; Weigt, Stefan; Witters, Hilda; Halder, Marlies

2014-08-01

The OECD validation study of the zebrafish embryo acute toxicity test (ZFET) for acute aquatic toxicity testing evaluated the ZFET reproducibility by testing 20 chemicals at 5 different concentrations in 3 independent runs in at least 3 laboratories. Stock solutions and test concentrations were analytically confirmed for 11 chemicals. Newly fertilised zebrafish eggs (20/concentration and control) were exposed for 96h to chemicals. Four apical endpoints were recorded daily as indicators of acute lethality: coagulation of the embryo, lack of somite formation, non-detachment of the tail bud from the yolk sac and lack of heartbeat. Results (LC50 values for 48/96h exposure) show that the ZFET is a robust method with a good intra- and inter-laboratory reproducibility (CV<30%) for most chemicals and laboratories. The reproducibility was lower (CV>30%) for some very toxic or volatile chemicals, and chemicals tested close to their limit of solubility. The ZFET is now available as OECD Test Guideline 236. Considering the high predictive capacity of the ZFET demonstrated by Belanger et al. (2013) in their retrospective analysis of acute fish toxicity and fish embryo acute toxicity data, the ZFET is ready to be considered for acute fish toxicity for regulatory purposes. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Embryotoxicity of nitrophenols to the early life stages of zebrafish (Danio rerio).

PubMed

Ceylan, Zeynep; Şişman, Turgay; Yazıcı, Zehra; Altıkat, Aysun Özen

2016-08-01

The nitrophenols (NPs) are water-soluble compounds. These compounds pose a significant health threat since they are priority environmental pollutants. In this study, 2-Nitrophenol (2NP) and 2,4-dinitrophenol (DNP) were examined for embryo and early life stage toxicity in zebrafish (Danio rerio). Acute toxicity and teratogenicity of 2NP and DNP were tested for 4 days using zebrafish embryos. The typical lesions observed were no somite formation, incomplete eye and head development, tail curvature, weak pigmentation (≤48 hours postfertilization (hpf)), kyphosis, scoliosis, yolk sac deformity, and nonpigmentation (72 hpf). Also, embryo and larval mortality increased and hatching success decreased. The severity of abnormalities and mortalities were concentration- and compound-dependent. Of the compounds tested, 2,4-DNP was found to be highly toxic to the fish embryos following exposure. The median lethal concentrations and median effective concentrations for 2NP are 18.7 mg/L and 7.9 mg/L, respectively; the corresponding values for DNP are 9.65 mg/L and 3.05 mg/L for 48 h. The chorda deformity was the most sensitive endpoint measured. It is suggested that the embryotoxicity may be mediated by an oxidative phosphorylation uncoupling mechanism. This article is the first to describe the teratogenicity and embryotoxicity of two NPs to the early life stages of zebrafish. © The Author(s) 2014.

The Chromatin Regulator Brpf1 Regulates Embryo Development and Cell Proliferation*

PubMed Central

You, Linya; Yan, Kezhi; Zou, Jinfeng; Zhao, Hong; Bertos, Nicholas R.; Park, Morag; Wang, Edwin; Yang, Xiang-Jiao

2015-01-01

With hundreds of chromatin regulators identified in mammals, an emerging issue is how they modulate biological and pathological processes. BRPF1 (bromodomain- and PHD finger-containing protein 1) is a unique chromatin regulator possessing two PHD fingers, one bromodomain and a PWWP domain for recognizing multiple histone modifications. In addition, it binds to the acetyltransferases MOZ, MORF, and HBO1 (also known as KAT6A, KAT6B, and KAT7, respectively) to promote complex formation, restrict substrate specificity, and enhance enzymatic activity. We have recently showed that ablation of the mouse Brpf1 gene causes embryonic lethality at E9.5. Here we present systematic analyses of the mutant animals and demonstrate that the ablation leads to vascular defects in the placenta, yolk sac, and embryo proper, as well as abnormal neural tube closure. At the cellular level, Brpf1 loss inhibits proliferation of embryonic fibroblasts and hematopoietic progenitors. Molecularly, the loss reduces transcription of a ribosomal protein L10 (Rpl10)-like gene and the cell cycle inhibitor p27, and increases expression of the cell-cycle inhibitor p16 and a novel protein homologous to Scp3, a synaptonemal complex protein critical for chromosome association and embryo survival. These results uncover a crucial role of Brpf1 in controlling mouse embryo development and regulating cellular and gene expression programs. PMID:25773539

Escherichia coli O78 isolated from septicemic lambs shows high pathogenicity in a zebrafish model.

PubMed

Kjelstrup, Cecilie K; Barber, Amelia E; Norton, J Paul; Mulvey, Matthew A; L'Abée-Lund, Trine M

2017-01-25

The pathogenicity of Escherichia coli O78 strain K46, originally isolated from an outbreak of septicemia in neonatal lambs, was investigated in zebrafish embryo and murine models of infection. Its biofilm potential, cellulose production, and the expression of type 1 pili and curli fimbriae were measured by in vitro assays. The strain was highly pathogenic in the zebrafish embryo model of infection, where it killed all embryos within 24 h post inoculation (hpi) at doses as low as 1000 colony forming units. Zebrafish embryos inoculated with similar doses of commensal E. coli strains showed no signs of disease, and cleared the bacteria within 24 h. E. coli K46 colonized the murine gut at the same level as the uropathogenic E. coli (UPEC) reference strain CFT073 in CBA/J mice after oral inoculation, but infected the murine bladder significantly less than CFT073 after transurethral inoculation. Type 1 pili were clearly expressed by E. coli K46, while curli fimbriae and cellulose production were weakly expressed. The ability to produce biofilm varied in different growth media, but overall E. coli K46 was a poorer biofilm producer compared to the reference strain E. coli UTI89. In conclusion, the zebrafish lethality model provides further evidence that E. coli K46 is highly pathogenic and might be useful in future studies to identify bacterial virulence factors.

Abelson Interactor 1 (Abi1) and Its Interaction with Wiskott-Aldrich Syndrome Protein (Wasp) Are Critical for Proper Eye Formation in Xenopus Embryos*

PubMed Central

Singh, Arvinder; Winterbottom, Emily F.; Ji, Yon Ju; Hwang, Yoo-Seok; Daar, Ira O.

2013-01-01

Abl interactor 1 (Abi1) is a scaffold protein that plays a central role in the regulation of actin cytoskeleton dynamics as a constituent of several key protein complexes, and homozygous loss of this protein leads to embryonic lethality in mice. Because this scaffold protein has been shown in cultured cells to be a critical component of pathways controlling cell migration and actin regulation at cell-cell contacts, we were interested to investigate the in vivo role of Abi1 in morphogenesis during the development of Xenopus embryos. Using morpholino-mediated translation inhibition, we demonstrate that knockdown of Abi1 in the whole embryo, or specifically in eye field progenitor cells, leads to disruption of eye morphogenesis. Moreover, signaling through the Src homology 3 domain of Abi1 is critical for proper movement of retinal progenitor cells into the eye field and their appropriate differentiation, and this process is dependent upon an interaction with the nucleation-promoting factor Wasp (Wiskott-Aldrich syndrome protein). Collectively, our data demonstrate that the Abi1 scaffold protein is an essential regulator of cell movement processes required for normal eye development in Xenopus embryos and specifically requires an Src homology 3 domain-dependent interaction with Wasp to regulate this complex morphogenetic process. PMID:23558677

Market uptake of orphan drugs--a European analysis.

PubMed

Picavet, E; Annemans, L; Cleemput, I; Cassiman, D; Simoens, S

2012-12-01

Variations in market uptake of an orphan drug have important implications with respect to access to care and inequality of treatment. Therefore, the aim of this study was to quantify both the sales and volume uptake of orphan drugs in Europe and to assess whether a country's gross domestic product (GDP) and/or health technology assessment (HTA) influences the orphan drugs' market uptake. We analysed the numbers of orphan drugs launched and the sales and volume uptake for 17 orphan drugs in 23 European countries from 2001 until the beginning of 2010 using the IMS Health database. Countries were clustered based on GDP and the availability of a formal HTA-organization. The uptake of orphan drugs varied across European countries. The highest volumes and contributions of orphan drugs in the first year occurred in countries with a high GDP (and implicitly, a higher budget for healthcare), independently of the existence of an HTA-organization. In contrast, in countries with a low GDP, orphan drugs were less available when there was a formal HTA-organization. There, budgetary restrictions can cause the exclusion of less cost-effective orphan drugs. We observed substantial variation in the market uptake of orphan drugs. Such variation may have important implications with respect to access to care and inequality of treatment. The uptake of orphan drugs could be promoted through the clinical added value of orphan drugs (CAVOD) project and various conditional pricing and reimbursement mechanisms. © 2012 Blackwell Publishing Ltd.

HIV infection and sexual risk behaviour among youth who have experienced orphanhood: systematic review and meta-analysis

PubMed Central

2011-01-01

Background Previous research has suggested that orphaned children and adolescents might have elevated risk for HIV infection. We examined the state of evidence regarding the association between orphan status and HIV risk in studies of youth aged 24 years and younger. Methods Using systematic review methodology, we identified 10 studies reporting data from 12 countries comparing orphaned and non-orphaned youth on HIV-related risk indicators, including HIV serostatus, other sexually transmitted infections, pregnancy and sexual behaviours. We meta-analyzed data from six studies reporting prevalence data on the association between orphan status and HIV serostatus, and we qualitatively summarized data from all studies on behavioural risk factors for HIV among orphaned youth. Results Meta-analysis of HIV testing data from 19,140 participants indicated significantly greater HIV seroprevalence among orphaned (10.8%) compared with non-orphaned youth (5.9%) (odds ratio = 1.97; 95% confidence interval = 1.41-2.75). Trends across studies showed evidence for greater sexual risk behaviour in orphaned youth. Conclusions Studies on HIV risk in orphaned populations, which mostly include samples from sub-Saharan Africa, show nearly two-fold greater odds of HIV infection among orphaned youth and higher levels of sexual risk behaviour than among their non-orphaned peers. Interventions to reduce risk for HIV transmission in orphaned youth are needed to address the sequelae of parental illness and death that might contribute to sexual risk and HIV infection. PMID:21592368

The importance of HIV prevention messaging for orphaned youth in Zimbabwe

PubMed Central

Haney, Erica; Singh, Kavita

2014-01-01

The AIDS epidemic has contributed to a drastic increase in the number of orphans in Zimbabwe. Female adolescent orphans are particularly in jeopardy of contracting HIV due to disadvantages including extreme poverty, low education, and the absent of parental oversight which can lead to higher risk-taking sexual behaviors. By understanding where girls receive education about HIV and who they rely on for information, organizations can effectively modify existing programs to better target this at-risk population. For this study a household survey was conducted which included 216 orphans and 324 non-orphans (n=540), aged 12–17 years old, in the resource-poor setting of Hwange District, Zimbabwe. The aims of this paper were to examine the differences between orphans and non-orphans in HIV prevention message exposure, level of motivation for learning about HIV, and communication with caregivers about safe sex. The household survey revealed that younger orphans, aged 12–15 years old, were more motivated to learn about HIV and had greater HIV messaging exposure in school than non-orphans. These exposure and differences in the levels of motivation between groups dissipated at older ages. Our research also discovered less caregiver communication among orphans than non-orphans. Our findings suggest that HIV programs targeting orphans need to do a better job at keeping older orphans interested in HIV prevention at a time when it matters most. Furthermore, intervention strategies that provide caregiver support are instrumental in effectively delivering prevention messages to girls at home. PMID:22293040

The importance of HIV prevention messaging for orphaned youth in Zimbabwe.

PubMed

Haney, Erica; Singh, Kavita

2012-01-01

The AIDS epidemic has contributed to a drastic increase in the number of orphans in Zimbabwe. Female adolescent orphans are particularly in jeopardy of contracting HIV due to disadvantages including extreme poverty, low education, and the absent of parental oversight which can lead to higher risk-taking sexual behaviors. By understanding where girls receive education about HIV and who they rely on for information, organizations can effectively modify existing programs to better target this at-risk population. For this study a household survey was conducted which included 216 orphans and 324 non-orphans (n=540), aged 12-17 years, in the resource-poor setting of Hwange District, Zimbabwe. The aims of this article were to examine the differences between orphans and non-orphans in HIV prevention message exposure, level of motivation for learning about HIV, and communication with caregivers about safe sex. The household survey revealed that younger orphans, aged 12-15 years, were more motivated to learn about HIV and had greater HIV messaging exposure in school than non-orphans. These exposure and differences in the levels of motivation between groups dissipated at older ages. Our research also discovered less caregiver communication among orphans than non-orphans. Our findings suggest that HIV programs targeting orphans need to do a better job at keeping older orphans interested in HIV prevention at a time when it matters most. Furthermore, intervention strategies that provide caregiver support are instrumental in effectively delivering prevention messages to girls at home.

Ethical imperatives of timely access to orphan drugs: is possible to reconcile economic incentives and patients' health needs?

PubMed

Rodriguez-Monguio, R; Spargo, T; Seoane-Vazquez, E

2017-01-05

More than 6,800 rare diseases and conditions have been identified in the US, which affect 25-30 million Americans. In 1983, the US Congress enacted the Orphan Drug Act (ODA) to encourage the development and marketing of drugs to treat rare diseases and conditions. This study analyzed all orphan designations and FDA approvals since 1983 through 2015, discussed the effectiveness of incentives for the development of treatments for rare diseases, and reflected on the ethical imperatives for timely access to orphan drugs. Study data were derived from the Food and Drug Administration (FDA) Orange Book and the Office of Orphan Drugs Development. A search was conducted to assess literature on the ethical principles and economic incentives for the development of orphan drugs. In the period 1983-2015, the FDA granted 3,647 orphan drug designations and 554 orphan drug approvals. The orphan drug approvals corresponded to 438 different brand names. Cancer was the therapeutic area with the highest number of approvals. The increased number of patients with rare diseases and the growth in the cost of orphan drugs pose a significant economic burden for patients, public programs and private third party payers. Regulatory differences to qualify for orphan designation and various population thresholds employed by the FDA and the European Medicines Agency lead to further unmet health needs for patients with rare diseases and aggravate health inequities. There is no societal consensus on the population and economic thresholds, the drug effectiveness indicator(s), or the societal value to be placed for the approval and reimbursement of orphan drugs. Orphan drug development and marketing in the US concentrate in few therapeutic areas. Despite the increase in the number of FDA approved orphan drugs, the unmet needs of patients with rare diseases evidence that the current incentives are not efficiently stimulating orphan drug development. There is need to balance economic incentives to stimulate the development and marketing of orphan drugs without jeopardizing patients' access to treatment. Thus, aligning pharmaceutical companies' incentives with societal budgetary constraints is necessary and the ethical imperatives of timely access to orphan drugs need to be agreed upon.

Lack of centrioles and primary cilia in STIL−/− mouse embryos

PubMed Central

David, Ahuvit; Liu, Fengying; Tibelius, Alexandra; Vulprecht, Julia; Wald, Diana; Rothermel, Ulrike; Ohana, Reut; Seitel, Alexander; Metzger, Jasmin; Ashery-Padan, Ruth; Meinzer, Hans-Peter; Gröne, Hermann-Josef; Izraeli, Shai; Krämer, Alwin

2014-01-01

Although most animal cells contain centrosomes, consisting of a pair of centrioles, their precise contribution to cell division and embryonic development is unclear. Genetic ablation of STIL, an essential component of the centriole replication machinery in mammalian cells, causes embryonic lethality in mice around mid gestation associated with defective Hedgehog signaling. Here, we describe, by focused ion beam scanning electron microscopy, that STIL−/− mouse embryos do not contain centrioles or primary cilia, suggesting that these organelles are not essential for mammalian development until mid gestation. We further show that the lack of primary cilia explains the absence of Hedgehog signaling in STIL−/− cells. Exogenous re-expression of STIL or STIL microcephaly mutants compatible with human survival, induced non-templated, de novo generation of centrioles in STIL−/− cells. Thus, while the abscence of centrioles is compatible with mammalian gastrulation, lack of centrioles and primary cilia impairs Hedgehog signaling and further embryonic development. PMID:25486474

Lack of centrioles and primary cilia in STIL(-/-) mouse embryos.

PubMed

David, Ahuvit; Liu, Fengying; Tibelius, Alexandra; Vulprecht, Julia; Wald, Diana; Rothermel, Ulrike; Ohana, Reut; Seitel, Alexander; Metzger, Jasmin; Ashery-Padan, Ruth; Meinzer, Hans-Peter; Gröne, Hermann-Josef; Izraeli, Shai; Krämer, Alwin

2014-01-01

Although most animal cells contain centrosomes, consisting of a pair of centrioles, their precise contribution to cell division and embryonic development is unclear. Genetic ablation of STIL, an essential component of the centriole replication machinery in mammalian cells, causes embryonic lethality in mice around mid gestation associated with defective Hedgehog signaling. Here, we describe, by focused ion beam scanning electron microscopy, that STIL(-/-) mouse embryos do not contain centrioles or primary cilia, suggesting that these organelles are not essential for mammalian development until mid gestation. We further show that the lack of primary cilia explains the absence of Hedgehog signaling in STIL(-/-) cells. Exogenous re-expression of STIL or STIL microcephaly mutants compatible with human survival, induced non-templated, de novo generation of centrioles in STIL(-/-) cells. Thus, while the abscence of centrioles is compatible with mammalian gastrulation, lack of centrioles and primary cilia impairs Hedgehog signaling and further embryonic development.

Drosophila I-R hybrid dysgenesis is associated with catastrophic meiosis and abnormal zygote formation.

PubMed

Orsi, Guillermo A; Joyce, Eric F; Couble, Pierre; McKim, Kim S; Loppin, Benjamin

2010-10-15

The Drosophila I-R type of hybrid dysgenesis is a sterility syndrome (SF sterility) associated with the mobilization of the I retrotransposon in female germ cells. SF sterility results from a maternal-effect embryonic lethality whose origin has remained unclear since its discovery about 40 years ago. Here, we show that meiotic divisions in SF oocytes are catastrophic and systematically fail to produce a functional female pronucleus at fertilization. As a consequence, most embryos from SF females rapidly arrest their development with aneuploid or damaged nuclei, whereas others develop as non-viable, androgenetic haploid embryos. Finally, we show that, in contrast to mutants affecting the biogenesis of piRNAs, SF egg chambers do not accumulate persistent DNA double-strand breaks, suggesting that I-element activity might perturb the functional organization of meiotic chromosomes without triggering an early DNA damage response.

NgBR is essential for endothelial cell glycosylation and vascular development.

PubMed

Park, Eon Joo; Grabińska, Kariona A; Guan, Ziqiang; Sessa, William C

2016-02-01

NgBR is a transmembrane protein identified as a Nogo-B-interacting protein and recently has been shown to be a subunit required for cis-prenyltransferase (cisPTase) activity. To investigate the integrated role of NgBR in vascular development, we have characterized endothelial-specific NgBR knockout embryos. Here, we show that endothelial-specific NgBR knockout results in embryonic lethality due to vascular development defects in yolk sac and embryo proper. Loss of NgBR in endothelial cells reduces proliferation and promotes apoptosis of the cells largely through defects in the glycosylation of key endothelial proteins including VEGFR2, VE-cadherin, and CD31, and defective glycosylation can be rescued by treatment with the end product of cisPTase activity, dolichol phosphate. Moreover, NgBR functions in endothelial cells during embryogenesis are Nogo-B independent. These data uniquely show the importance of NgBR and protein glycosylation during vascular development. © 2016 The Authors.

Generation of Healthy Mice from Gene-Corrected Disease-Specific Induced Pluripotent Stem Cells

PubMed Central

Rittelmeyer, Ina; Sharma, Amar Deep; Sgodda, Malte; Zaehres, Holm; Bleidißel, Martina; Greber, Boris; Gentile, Luca; Han, Dong Wook; Rudolph, Cornelia; Steinemann, Doris; Schambach, Axel; Ott, Michael; Schöler, Hans R.; Cantz, Tobias

2011-01-01

Using the murine model of tyrosinemia type 1 (fumarylacetoacetate hydrolase [FAH] deficiency; FAH −/− mice) as a paradigm for orphan disorders, such as hereditary metabolic liver diseases, we evaluated fibroblast-derived FAH −/−-induced pluripotent stem cells (iPS cells) as targets for gene correction in combination with the tetraploid embryo complementation method. First, after characterizing the FAH −/− iPS cell lines, we aggregated FAH −/−-iPS cells with tetraploid embryos and obtained entirely FAH −/−-iPS cell–derived mice that were viable and exhibited the phenotype of the founding FAH −/− mice. Then, we transduced FAH cDNA into the FAH −/−-iPS cells using a third-generation lentiviral vector to generate gene-corrected iPS cells. We could not detect any chromosomal alterations in these cells by high-resolution array CGH analysis, and after their aggregation with tetraploid embryos, we obtained fully iPS cell–derived healthy mice with an astonishing high efficiency for full-term development of up to 63.3%. The gene correction was validated functionally by the long-term survival and expansion of FAH-positive cells of these mice after withdrawal of the rescuing drug NTBC (2-(2-nitro-4-fluoromethylbenzoyl)-1,3-cyclohexanedione). Furthermore, our results demonstrate that both a liver-specific promoter (transthyretin, TTR)-driven FAH transgene and a strong viral promoter (from spleen focus-forming virus, SFFV)-driven FAH transgene rescued the FAH-deficiency phenotypes in the mice derived from the respective gene-corrected iPS cells. In conclusion, our data demonstrate that a lentiviral gene repair strategy does not abrogate the full pluripotent potential of fibroblast-derived iPS cells, and genetic manipulation of iPS cells in combination with tetraploid embryo aggregation provides a practical and rapid approach to evaluate the efficacy of gene correction of human diseases in mouse models. PMID:21765802

The availability and affordability of orphan drugs for rare diseases in China.

PubMed

Gong, Shiwei; Wang, Yingxiao; Pan, Xiaoyun; Zhang, Liang; Huang, Rui; Chen, Xin; Hu, Juanjuan; Xu, Yi; Jin, Si

2016-02-27

Orphan drugs are intended to treat, prevent or diagnose rare diseases. In recent years, China healthcare policy makers and patients have become increasingly concerned about orphan drug issues. However, very few studies have assessed the availability and affordability of orphan drugs for rare diseases in China. The aim of this study was to provide an overview of the availability and affordability of orphan drugs in China and to make suggestions to improve patient access to orphan drugs. Two components of the availability of orphan drugs were examined. Market availability was assessed by the extent to which orphan drugs were marketed in China with a comparison to orphan drugs in international markets, such as the U.S., EU and Japan. We conducted surveys and collected data from 24 tertiary public hospitals in China to measure hospital-level availability of orphan drugs. The affordability of orphan drugs was calculated using hospital dispensary prices and was expressed as days of average daily income required for the cost of a course of treatment. Affordability was also analyzed under the Chinese basic medical insurance system. Orphan drugs approved in the U.S., EU and Japan had 37.8%, 24.6% and 52.4% market availability in China, respectively. Median availability of 31 orphan drugs surveyed at the 24 tertiary public hospitals was 20.8% (very low). Within a periodic treatment course, the average treatment cost of 23 orphan drugs is approximately 4, 843. 5 USD, which equates to 505.6 days of per capita net income for an urban resident with a middle income (187.4 days for a high-income urban resident) or 1,582.8 days's income for a rural resident with a middle income (657.2 days for a high-income rural resident). Except for homoharringtonine, 22 orphan drugs for 14 rare diseases were unaffordable for the most of residents in China. With 5% out-of-pocket expenses, only three generics could be afforded by middle-income residents, whereas seven drugs for high-income urban residents. The Chinese government can take more responsibility for improving the availability and affordability of orphan drugs through setting up incentive policies and public platforms for sharing of orphan drug information. Control of the high price of orphan drugs, combined with a joint funding model from both government and private enterprise can efficiently reduce the economic burden of affected patients in China.

Nickel affects gill and muscle development in oriental fire-bellied toad (Bombina orientalis) embryos.

PubMed

Park, Chan Jin; Song, Sang Ha; Kim, Dae Han; Gye, Myung Chan

2017-01-01

The developmental toxicity of nickel was examined in the embryos of Bombina orientalis, a common amphibian in Korea. Based on a standard frog embryo teratogenesis assay, the LC 50 and EC 50 for malformation of nickel after 168h of treatment were 33.8μM and 5.4μM, respectively. At a lethal concentration (100μM), nickel treatment decreased the space between gill filaments and caused epithelial swelling and abnormal fusion of gill filaments. These findings suggest that nickel affects the functional development of gills, leading to embryonic death. At sublethal concentrations (1-10μM), nickel produced multiple embryonic abnormalities, including bent tail and tail dysplasia. At 10μM, nickel significantly decreased tail length and tail muscle fiber density in tadpoles, indicating inhibition of myogenic differentiation. Before hatching, the pre-muscular response to muscular response stages (stages 26-31) were the most sensitive period to nickel with respect to tail muscle development. During these stages, MyoD mRNA was upregulated, whereas myogenic regulatory factor 4 mRNA was downregulated by 0.1μM nickel. Calcium-dependent kinase activities in muscular response stage embryos were significantly decreased by nickel, whereas these activities were restored by exogenous calcium. In tadpoles, 10μM nickel significantly decreased the expression of the myosin heavy chain and the 12/101 muscle marker protein in the tail. Expression was restored by exogenous calcium. Our results indicate that nickel affects muscle development by disrupting calcium-dependent myogenesis in developing B. orientalis embryos. Copyright © 2016 Elsevier B.V. All rights reserved.

Lethal and teratogenic effects of phenol on Bufo arenarum embryos.

PubMed

Paisio, Cintia Elizabeth; Agostini, Elizabeth; González, Paola Solange; Bertuzzi, Mabel Lucía

2009-08-15

Phenol and their derivatives are used in several industries and they have a high potential toxicity for animal and plant species. They were found in variable concentrations, as high as 1000 mg/L, in industrial wastewater and, they are often discharged into the environment. Amphibian embryos are useful indicators of environmental pollution. However, to our knowledge, there are not studies focussed on the toxic effects of phenol on Bufo arenarum, which is an anuran widely distributed in South America. Therefore, the effect of phenol on the survival and morphogenesis of these amphibian embryos was evaluated by means of AMPHITOX test. Embryos at 25 stage of development (acute test) and embryos at 2-4 blastomers stage (early life stage test), were exposed to phenol solutions in concentrations ranging from 25 to 250 mg/L, which were frequently found in the environment. Mortality and malformations were registered each 24h. LC(50), LC(99), NOEC, TC(50) and TI(50) values were 183.70, 250, 60, 113 mg/L and 1.62, respectively, at 96 h of treatment. Mortality and the percentage of malformations increased with increasing phenol concentrations. Teratogenic effects more frequently produced by phenol were: axial flexure, persistent yolk plug and different abnormalities which caused death of blastulae. Moreover, other malformations were registered, such as irregular form, acephalism, edema, axial shortening and underdevelopment of gills, among others. Larvae of B. arenarum, at early embryonic stages (blastulae), showed higher sensitivity to phenol than tadpoles at stage 25. Results confirm high susceptibility of amphibians to phenol and that environmental concentrations of this pollutant might be harmful to these populations.

Impaired embryonic development in glucose-6-phosphate dehydrogenase-deficient Caenorhabditis elegans due to abnormal redox homeostasis induced activation of calcium-independent phospholipase and alteration of glycerophospholipid metabolism.

PubMed

Chen, Tzu-Ling; Yang, Hung-Chi; Hung, Cheng-Yu; Ou, Meng-Hsin; Pan, Yi-Yun; Cheng, Mei-Ling; Stern, Arnold; Lo, Szecheng J; Chiu, Daniel Tsun-Yee

2017-01-12

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a commonly pervasive inherited disease in many parts of the world. The complete lack of G6PD activity in a mouse model causes embryonic lethality. The G6PD-deficient Caenorhabditis elegans model also shows embryonic death as indicated by a severe hatching defect. Although increased oxidative stress has been implicated in both cases as the underlying cause, the exact mechanism has not been clearly delineated. In this study with C. elegans, membrane-associated defects, including enhanced permeability, defective polarity and cytokinesis, were found in G6PD-deficient embryos. The membrane-associated abnormalities were accompanied by impaired eggshell structure as evidenced by a transmission electron microscopic study. Such loss of membrane structural integrity was associated with abnormal lipid composition as lipidomic analysis revealed that lysoglycerophospholipids were significantly increased in G6PD-deficient embryos. Abnormal glycerophospholipid metabolism leading to defective embryonic development could be attributed to the increased activity of calcium-independent phospholipase A 2 (iPLA) in G6PD-deficient embryos. This notion is further supported by the fact that the suppression of multiple iPLAs by genetic manipulation partially rescued the embryonic defects in G6PD-deficient embryos. In addition, G6PD deficiency induced disruption of redox balance as manifested by diminished NADPH and elevated lipid peroxidation in embryos. Taken together, disrupted lipid metabolism due to abnormal redox homeostasis is a major factor contributing to abnormal embryonic development in G6PD-deficient C. elegans.

Three-dimensional microCT imaging of murine embryonic development from immediate post-implantation to organogenesis: application for phenotyping analysis of early embryonic lethality in mutant animals.

PubMed

Ermakova, Olga; Orsini, Tiziana; Gambadoro, Alessia; Chiani, Francesco; Tocchini-Valentini, Glauco P

2018-04-01

In this work, we applied three-dimensional microCT imaging to study murine embryogenesis in the range from immediate post-implantation period (embryonic day 5.5) to mid-gestation (embryonic day 12.5) with the resolution up to 1.4 µm/voxel. Also, we introduce an imaging procedure for non-invasive volumetric estimation of an entire litter of embryos within the maternal uterine structures. This method allows for an accurate, detailed and systematic morphometric analysis of both embryonic and extra-embryonic components during embryogenesis. Three-dimensional imaging of unperturbed embryos was performed to visualize the egg cylinder, primitive streak, gastrulation and early organogenesis stages of murine development in the C57Bl6/N mouse reference strain. Further, we applied our microCT imaging protocol to determine the earliest point when embryonic development is arrested in a mouse line with knockout for tRNA splicing endonuclease subunit Tsen54 gene. Our analysis determined that the embryonic development in Tsen54 null embryos does not proceed beyond implantation. We demonstrated that application of microCT imaging to entire litter of non-perturbed embryos greatly facilitate studies to unravel gene function during early embryogenesis and to determine the precise point at which embryonic development is arrested in mutant animals. The described method is inexpensive, does not require lengthy embryos dissection and can be applicable for detailed analysis of mutant mice at laboratory scale as well as for high-throughput projects.

Deciphering and Imaging Pathogenesis and Cording of Mycobacterium abscessus in Zebrafish Embryos

PubMed Central

Bernut, Audrey; Dupont, Christian; Sahuquet, Alain; Herrmann, Jean-Louis; Lutfalla, Georges; Kremer, Laurent

2015-01-01

Zebrafish (Danio rerio) embryos are increasingly used as an infection model to study the function of the vertebrate innate immune system in host-pathogen interactions. The ease of obtaining large numbers of embryos, their accessibility due to external development, their optical transparency as well as the availability of a wide panoply of genetic/immunological tools and transgenic reporter line collections, contribute to the versatility of this model. In this respect, the present manuscript describes the use of zebrafish as an in vivo model system to investigate the chronology of Mycobacterium abscessus infection. This human pathogen can exist either as smooth (S) or rough (R) variants, depending on cell wall composition, and their respective virulence can be imaged and compared in zebrafish embryos and larvae. Micro-injection of either S or R fluorescent variants directly in the blood circulation via the caudal vein, leads to chronic or acute/lethal infections, respectively. This biological system allows high resolution visualization and analysis of the role of mycobacterial cording in promoting abscess formation. In addition, the use of fluorescent bacteria along with transgenic zebrafish lines harbouring fluorescent macrophages produces a unique opportunity for multi-color imaging of the host-pathogen interactions. This article describes detailed protocols for the preparation of homogenous M. abscessus inoculum and for intravenous injection of zebrafish embryos for subsequent fluorescence imaging of the interaction with macrophages. These techniques open the avenue to future investigations involving mutants defective in cord formation and are dedicated to understand how this impacts on M. abscessus pathogenicity in a whole vertebrate. PMID:26382225

What cell death does in development.

PubMed

Zakeri, Zahra; Penaloza, Carlos G; Smith, Kyle; Ye, Yixia; Lockshin, Richard A

2015-01-01

Cell death is prominent in gametogenesis and shapes and sculpts embryos. In non-mammalian embryos one sees little or no cell death prior to the maternal-zygotic transition, but, in mammalian embryos, characteristic deaths of one or two cells occur at the end of compaction and are apparently necessary for the separation of the trophoblast from the inner cell mass. Considerable sculpting of the embryo occurs by cell deaths during organogenesis, and appropriate cell numbers, especially in the CNS and in the immune system, are generated by massive overproduction of cells and selection of a few, with death of the rest. The timing, identity, and genetic control of specific cells that die have been well documented in Caenorhabditis, but in other embryos the stochastic nature of the deaths limit our ability to do more than identify the regions in which cells will die. Complete disruption of the cell death machinery can be lethal, but many mutations of the regulatory machinery yield only modest or no phenotypes, indicating substantial redundancy and compensation of regulatory mechanisms. Most of the deaths are apoptotic and are identified by techniques used to recognize apoptosis, but techniques identifying lysosomes (whether in dying or involuting cells or in the phagocytes that invade the tissue) also reveal patterns of cell death. Aberrant cell deaths that produce known phenotypes are typically localized, indicating that the mechanism of activating a programmed death in a specific region, rather than the mechanism of death, is aberrant. These results lead us to conclude that we need to know much more about the conversations among cells that lead cells to commit suicide.

Effects of mercury on the embryos and larvae of the freshwater teleosts: Etheostoma caeruleum and E. spectabile

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharp, J.R.

1994-12-31

A 24-h static renewal assay of five replicates of ten cleavage stage (8-1 6 cell) embryos each of the percid teleosts Etheostoma caeruleum (Ec) and E. spectabile (Es) were exposed to 0--100 ppb Hg++ (mercuric chloride) until all embryos had hatched or died. This assay was designed to determine concentration-specific and species-specific differences in embryonic mortality, teratogenesis, hatchability, viability of hatch, heart rate, and growth. In a separate assay embryos were exposed to lower mercury concentrations through a 30-d post hatch exposure to evaluate longer term effects on larval survival and growth. At 18 C, Etheostoma caeruleum and E. spectabilemore » have average incubation periods (time to hatch) and ova diameters of 12-d, 8-d; and 1.9mm, 1.2mm; respectively. Four median effective concentrations, as ppb Hg++, were estimated as a result of embryonic exposure: 96-LC50 (lethality), AB50 (abnormality), SH50 (successful hatch) and VH50 (viable hatch). The typical and predictable embryonic and larval terata were noted for both species. Cardiac pulsation rates (beats/minute) were significantly reduced at > 20 ppb for both species. Mean total length of first day hatch for Ec and Es was significantly shorter for embryo emerging from 5 ppb and 10 ppb, respectively. Post-hatch survival (after 30-d) for both species was significantly reduced at 5 ppb. Larval growth, after 30-d, was significantly less at 2.5 and 5 ppb for Ec and Es, respectively.« less

Access to Orphan Drugs: A Comprehensive Review of Legislations, Regulations and Policies in 35 Countries

PubMed Central

Gammie, Todd

2015-01-01

Objective To review existing regulations and policies utilised by countries to enable patient access to orphan drugs. Methods A review of the literature (1998 to 2014) was performed to identify relevant, peer-reviewed articles. Using content analysis, we synthesised regulations and policies for access to orphan drugs by type and by country. Results Fifty seven articles and 35 countries were included in this review. Six broad categories of regulation and policy instruments were identified: national orphan drug policies, orphan drug designation, marketing authorization, incentives, marketing exclusivity, and pricing and reimbursement. The availability of orphan drugs depends on individual country’s legislation and regulations including national orphan drug policies, orphan drug designation, marketing authorization, marketing exclusivity and incentives such as tax credits to ensure research, development and marketing. The majority of countries (27/35) had in place orphan drug legislation. Access to orphan drugs depends on individual country’s pricing and reimbursement policies, which varied widely between countries. High prices and insufficient evidence often limit orphan drugs from meeting the traditional health technology assessment criteria, especially cost-effectiveness, which may influence access. Conclusions Overall many countries have implemented a combination of legislations, regulations and policies for orphan drugs in the last two decades. While these may enable the availability and access to orphan drugs, there are critical differences between countries in terms of range and types of legislations, regulations and policies implemented. Importantly, China and India, two of the largest countries by population size, both lack national legislation for orphan medicines and rare diseases, which could have substantial negative impacts on their patient populations with rare diseases. PMID:26451948

Sexual risk among orphaned adolescents: is country-level HIV prevalence an important factor?

PubMed Central

Robertson, Laura; Gregson, Simon; Garnett, Geoff P.

2010-01-01

Previous studies from sub-Saharan Africa have found that orphans experience increased sexual risk compared to non-orphans. We developed a theoretical framework for the investigation of determinants of HIV risk and used it to generate specific hypotheses regarding the effect of country-level HIV prevalence on the sexual risk experience of orphans. We expected that countries with high HIV prevalence would experience a higher prevalence of orphanhood. We further hypothesised that orphans in countries with high HIV prevalence would experience increased sexual risk, compared to non-orphans, due to pressure on the extended family network, which is primarily responsible for the care of orphans in sub-Saharan Africa, resulting in poorer standards of care and guidance. We used hierarchical logistic regression models to investigate this hypothesis using cross-sectional, Demographic and Health Survey data from 10 sub-Saharan African countries. We found that countries with high HIV prevalence did indeed have higher prevalence of orphanhood. We also found that, amongst female adolescents, maternal and double orphans were significantly more likely to have started sex than non-orphans in countries with high HIV prevalence but were not at increased risk in low HIV prevalence countries. This effect of country-level HIV prevalence on the sexual risk of orphans was not explained by household level factors such as wealth, overcrowding or age of the household head. The same pattern of risk was not observed for male adolescents — male orphans were not more likely to have started sex than non-orphans. This suggests that orphaned adolescent women are an important target group for HIV prevention and that efforts should be made to integrate prevention messages into existing support programmes for orphans and vulnerable children. PMID:20552462

21 CFR 316.24 - Granting orphan-drug designation.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Granting orphan-drug designation. 316.24 Section 316.24 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE ORPHAN DRUGS Designation of an Orphan Drug § 316.24 Granting orphan-drug designation...

21 CFR 316.24 - Granting orphan-drug designation.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Granting orphan-drug designation. 316.24 Section 316.24 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE ORPHAN DRUGS Designation of an Orphan Drug § 316.24 Granting orphan-drug designation...

21 CFR 316.24 - Granting orphan-drug designation.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Granting orphan-drug designation. 316.24 Section 316.24 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE ORPHAN DRUGS Designation of an Orphan Drug § 316.24 Granting orphan-drug designation...

21 CFR 316.24 - Granting orphan-drug designation.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Granting orphan-drug designation. 316.24 Section 316.24 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE ORPHAN DRUGS Designation of an Orphan Drug § 316.24 Granting orphan-drug designation...

Pricing and reimbursement of orphan drugs: the need for more transparency

PubMed Central

2011-01-01

Pricing and reimbursement of orphan drugs are an issue of high priority for policy makers, legislators, health care professionals, industry leaders, academics and patients. This study aims to conduct a literature review to provide insight into the drivers of orphan drug pricing and reimbursement. Although orphan drug pricing follows the same economic logic as drug pricing in general, the monopolistic power of orphan drugs results in high prices: a) orphan drugs benefit from a period of marketing exclusivity; b) few alternative health technologies are available; c) third-party payers and patients have limited negotiating power; d) manufacturers attempt to maximise orphan drug prices within the constraints of domestic pricing and reimbursement policies; and e) substantial R&D costs need to be recouped from a small number of patients. Although these conditions apply to some orphan drugs, they do not apply to all orphan drugs. Indeed, the small number of patients treated with an orphan drug and the limited economic viability of orphan drugs can be questioned in a number of cases. Additionally, manufacturers have an incentive to game the system by artificially creating monopolistic market conditions. Given their high price for an often modest effectiveness, orphan drugs are unlikely to provide value for money. However, additional criteria are used to inform reimbursement decisions in some countries. These criteria may include: the seriousness of the disease; the availability of other therapies to treat the disease; and the cost to the patient if the medicine is not reimbursed. Therefore, the maximum cost per unit of outcome that a health care payer is willing to pay for a drug could be set higher for orphan drugs to which society attaches a high social value. There is a need for a transparent and evidence-based approach towards orphan drug pricing and reimbursement. Such an approach should be targeted at demonstrating the relative effectiveness, cost-effectiveness and economic viability of orphan drugs with a view to informing pricing and reimbursement decisions. PMID:21682893

Pricing and reimbursement of orphan drugs: the need for more transparency.

PubMed

Simoens, Steven

2011-06-17

Pricing and reimbursement of orphan drugs are an issue of high priority for policy makers, legislators, health care professionals, industry leaders, academics and patients. This study aims to conduct a literature review to provide insight into the drivers of orphan drug pricing and reimbursement. Although orphan drug pricing follows the same economic logic as drug pricing in general, the monopolistic power of orphan drugs results in high prices: a) orphan drugs benefit from a period of marketing exclusivity; b) few alternative health technologies are available; c) third-party payers and patients have limited negotiating power; d) manufacturers attempt to maximise orphan drug prices within the constraints of domestic pricing and reimbursement policies; and e) substantial R&D costs need to be recouped from a small number of patients. Although these conditions apply to some orphan drugs, they do not apply to all orphan drugs. Indeed, the small number of patients treated with an orphan drug and the limited economic viability of orphan drugs can be questioned in a number of cases. Additionally, manufacturers have an incentive to game the system by artificially creating monopolistic market conditions. Given their high price for an often modest effectiveness, orphan drugs are unlikely to provide value for money. However, additional criteria are used to inform reimbursement decisions in some countries. These criteria may include: the seriousness of the disease; the availability of other therapies to treat the disease; and the cost to the patient if the medicine is not reimbursed. Therefore, the maximum cost per unit of outcome that a health care payer is willing to pay for a drug could be set higher for orphan drugs to which society attaches a high social value. There is a need for a transparent and evidence-based approach towards orphan drug pricing and reimbursement. Such an approach should be targeted at demonstrating the relative effectiveness, cost-effectiveness and economic viability of orphan drugs with a view to informing pricing and reimbursement decisions.

Two O-linked N-acetylglucosamine transferase genes of Arabidopsis thaliana L. Heynh. have overlapping functions necessary for gamete and seed development.

PubMed Central

Hartweck, Lynn M; Scott, Cheryl L; Olszewski, Neil E

2002-01-01

The Arabidopsis SECRET AGENT (SEC) and SPINDLY (SPY) proteins are similar to animal O-linked N-acetylglucosamine transferases (OGTs). OGTs catalyze the transfer of N-acetylglucosamine (GlcNAc) from UDP-GlcNAc to Ser/Thr residues of proteins. In animals, O-GlcNAcylation has been shown to affect protein activity, stability, and/or localization. SEC protein expressed in Escherichia coli had autocatalytic OGT activity. To determine the function of SEC in plants, two tDNA insertional mutants were identified and analyzed. Although sec mutant plants did not exhibit obvious phenotypes, sec and spy mutations had a synthetic lethal interaction. This lethality was incompletely penetrant in gametes and completely penetrant postfertilization. The rate of both female and male sec spy gamete transmission was higher in plants heterozygous for both mutations than in plants heterozygous for sec and homozygous for spy. Double-mutant embryos aborted at various stages of development and no double-mutant seedlings were obtained. These results indicate that OGT activity is required during gametogenesis and embryogenesis with lethality occurring when parentally derived SEC, SPY, and/or O-GlcNAcylated proteins become limiting. PMID:12136030

The dual-specificity protein phosphatase DUSP9/MKP-4 is essential for placental function but is not required for normal embryonic development.

PubMed

Christie, Graham R; Williams, David J; Macisaac, Fiona; Dickinson, Robin J; Rosewell, Ian; Keyse, Stephen M

2005-09-01

To elucidate the physiological role(s) of DUSP9 (dual-specificity phosphatase 9), also known as MKP-4 (mitogen-activated protein kinase [MAPK] phosphatase 4), the gene was deleted in mice. Crossing male chimeras with wild-type females resulted in heterozygous (DUSP9(+/-)) females. However, when these animals were crossed with wild-type (DUSP9(+/y)) males none of the progeny carried the targeted DUSP9 allele, indicating that both female heterozygous and male null (DUSP9(-/y)) animals die in utero. The DUSP9 gene is on the X chromosome, and this pattern of embryonic lethality is consistent with the selective inactivation of the paternal X chromosome in the extraembryonic tissues of the mouse, suggesting that DUSP9/MKP4 performs an essential function during placental development. Examination of embryos between 8 and 10.5 days postcoitum confirmed that lethality was due to a failure of labyrinth development, and this correlates exactly with the normal expression pattern of DUSP9/MKP-4 in the trophoblast giant cells and labyrinth of the placenta. Finally, when the placental defect was rescued, male null (DUSP9(-/y)) embryos developed to term, appeared normal, and were fertile. Our results indicate that DUSP9/MKP-4 is essential for placental organogenesis but is otherwise dispensable for mammalian embryonic development and highlights the critical role of dual-specificity MAPK phosphatases in the regulation of developmental outcomes in vertebrates.

Involvement of retinol dehydrogenase 10 in embryonic patterning and rescue of its loss of function by maternal retinaldehyde treatment

PubMed Central

Rhinn, Muriel; Schuhbaur, Brigitte; Niederreither, Karen; Dollé, Pascal

2011-01-01

Retinoic acid (RA), an active vitamin A metabolite, is a key signaling molecule in vertebrate embryos. Morphogenetic RA gradients are thought to be set up by tissue-specific actions of retinaldehyde dehydrogenases (RALDHs) and catabolizing enzymes. According to the species, two enzymatic pathways (β-carotene cleavage and retinol oxidation) generate retinaldehyde, the substrate of RALDHs. Placental species depend on maternal retinol transferred to the embryo. The retinol-to-retinaldehyde conversion was thought to be achieved by several redundant enzymes; however, a random mutagenesis screen identified retinol dehydrogenase 10 [Rdh10Trex allele; Sandell LL, et al. (2007) Genes Dev 21:1113–1124] as responsible for a homozygous lethal phenotype with features of RA deficiency. We report here the production and characterization of unique murine Rdh10 loss-of-function alleles generated by gene targeting. We show that although Rdh10−/− mutants die at an earlier stage than Rdh10Trex mutants, their molecular patterning defects do not reflect a complete state of RA deficiency. Furthermore, we were able to correct most developmental abnormalities by administering retinaldehyde to pregnant mothers, thereby obtaining viable Rdh10−/− mutants. This demonstrates the rescue of an embryonic lethal phenotype by simple maternal administration of the missing retinoid compound. These results underscore the importance of maternal retinoids in preventing congenital birth defects, and lead to a revised model of the importance of RDH10 and RALDHs in controlling embryonic RA distribution. PMID:21930923

Access to orphan drugs despite poor quality of clinical evidence

PubMed Central

Dupont, Alain G; Van Wilder, Philippe B

2011-01-01

AIM We analysed the Belgian reimbursement decisions of orphan drugs as compared with those of innovative drugs for more common but equally severe diseases, with special emphasis on the quality of clinical evidence. METHODS Using the National Health Insurance Agency administrative database, we evaluated all submitted orphan drug files between 2002 and 2007. A quality analysis of the clinical evidence in the orphan reimbursement files was performed. The evaluation reports of the French ‘Haute Autorité de Santé’, including the five-point scale parameter ‘Service Médical Rendu (SMR), were examined to compare disease severity. Chi-squared tests (at P < 0.05 significance level) were used to compare the outcome of the reimbursement decisions between orphan and non-orphan innovative medicines. RESULTS Twenty-five files of orphan drugs and 117 files of non-orphan drugs were evaluated. Twenty-two of 25 (88%) submissions of orphan drugs were granted reimbursement as opposed to 74 of the 117 (63%) non-orphan innovative medicines (P = 0.02). Only 52% of the 25 orphan drug files included a randomized controlled trial as opposed to 84% in a random control sample of 25 non-orphan innovative submissions (P < 0.01). The duration of drug exposure was in most cases far too short in relation to the natural history of the disease. CONCLUSIONS Orphan drug designation predicts reimbursement despite poor quality of clinical evidence. The evidence gap at market authorization should be reduced by post-marketing programmes, in which the centralized regulatory and the local reimbursement authorities collaborate in an efficient way across the European Union member states. PMID:21395641

Affordable orphan drugs: a role for not-for-profit organizations.

PubMed

Davies, Elin H; Fulton, Emma; Brook, Daniel; Hughes, Dyfrig A

2017-07-01

The success of the Regulation on Orphan Medicinal Products in the European Union is evidenced by the 127 orphan drugs that have had market authorization since 2000. However, the incentives aimed at stimulating research and development have had the unintended consequence of increasing drug cost, resulting in many orphan drugs not being cost-effective. Orphan drugs command an increasing share of the pharmaceutical market and account for a disproportionate amount of healthcare expenditure. Orphan drug ownership by socially motivated, not-for-profit organizations may facilitate access to more affordable orphan drugs, for the benefit of patients and healthcare systems alike. This study aims to describe opportunities for such organizations to become orphan drug Market Authorization Holders. We reviewed data on the ownership of EMA designated and approved orphan drugs, identified funding opportunities and business models for not-for-profit organizations, and summarised relevant legal and policy documents concerning intellectual property rights and drug regulation. Using repurposed drugs as a paradigm, this narrative review navigates the regulatory hurdles, describes the legal context and identifies funding opportunities, in a bid to facilitate and encourage not-for-profit organizations to lead on the development of affordable orphan drugs. Although the regulatory steps required to obtain an MA for an orphan drug are numerous and challenging, they are not insurmountable and can be achieved by not-for-profit organizations that are socially motivated to reduce the costs of orphan drugs to the payers of healthcare. Opportunities for orphan drug development resulting in affordable products lie mainly with repurposed drugs. © 2017 The British Pharmacological Society.

Influences of Reduced Expression of Maternal Bone Morphogenetic Protein 2 on Embryonic Development

PubMed Central

Singh, Ajeet P.; Castranio, Trisha; Scott, Greg; Guo, Dayong; Harris, Marie A.; Ray, Manas; Harris, Stephan E.; Mishina, Yuji

2009-01-01

Bone morphogenetic protein 2 (BMP2) was originally found by its osteoinductive ability, and recent genetic analyses have revealed that it plays critical roles during early embryogenesis, cardiogenesis, decidualization as well as skeletogenesis. During a course of evaluation of the conditional allele for Bmp2, we found that the presence of a neo cassette, a selection marker needed for gene targeting events in embryonic stem cells, in the 3’ untranslated region of exon 3 of Bmp2, reduced the expression levels of Bmp2 both in embryonic and maternal tissues. Some of the embryos that were genotyped as transheterozygous for the floxed allele with the neo cassette over the conventional null allele (fn/−) showed a lethal phenotype including defects in cephalic neural tube closure and ventral abdominal wall closure. Embryos exhibiting these abnormalities were increased when genotypes of the pregnant females were different; when expression levels of Bmp2 in maternal tissues were lower, a larger proportion of fn/− embryos exhibit these abnormalities. These results suggest that the expression levels of Bmp2 together in both in embryonic and maternal tissues influence the normal neural tube closure and body wall closure with different thresholds. PMID:18769073

Generation of embryos directly from embryonic stem cells by tetraploid embryo complementation reveals a role for GATA factors in organogenesis.

PubMed

Duncan, S A

2005-12-01

Gene targeting in ES (embryonic stem) cells has been used extensively to study the role of proteins during embryonic development. In the traditional procedure, this requires the generation of chimaeric mice by introducing ES cells into blastocysts and allowing them to develop to term. Once chimaeric mice are produced, they are bred into a recipient mouse strain to establish germline transmission of the allele of interest. Although this approach has been used very successfully, the breeding cycles involved are time consuming. In addition, genes that are essential for organogenesis often have roles in the formation of extra-embryonic tissues that are essential for early stages of post-implantation development. For example, mice lacking the GATA transcription factors, GATA4 or GATA6, arrest during gastrulation due to an essential role for these factors in differentiation of extra-embryonic endoderm. This lethality has frustrated the study of these factors during the development of organs such as the liver and heart. Extraembryonic defects can, however, be circumvented by generating clonal mouse embryos directly from ES cells by tetraploid complementation. Here, we describe the usefulness and efficacy of this approach using GATA factors as an example.

Developmental toxicity of Japanese medaka embryos by silver nanoparticles and released ions in the presence of humic acid.

PubMed

Kim, Jun Y; Kim, Ki-Tae; Lee, Byeong G; Lim, Byung J; Kim, Sang D

2013-06-01

The final destination point of nanoparticles is the environment, where they remain a long period; therefore, a deep understanding of the relationship between nanoparticles and the environmental factors is required. Japanese medaka embryos were exposed to two differently prepared AgNPs: freshly prepared AgNPs and aged AgNPs. With these two AgNP preparations, we studied the impacts of humic acid in terms of embryonic toxicity, as well as the behavior of AgNPs. Aged AgNPs exhibited a lower lethal concentration (LC50) value (1.44mg/L) compared to fresh AgNPs (3.53mg/L) through 96h acute toxicity tests, due to the release of silver ions, as confirmed by kinetic analysis. The presence of humic acids considerably reduced the toxicity of aged AgNPs due to complexation with silver ions. Agglomeration, induced by interactions with humic acid, might reduce the bioavailability of AgNPs to Japanese medaka embryos. This study demonstrates that aged AgNPs releasing more silver ions are more toxic than fresh AgNPs, and humic acids play a role in reducing the toxicity of aged AgNPs. Copyright © 2013 Elsevier Inc. All rights reserved.

Recognition of the CDEI motif GTCACATG by mouse nuclear proteins and interference with the early development of the mouse embryo.

PubMed Central

Blangy, A; Léopold, P; Vidal, F; Rassoulzadegan, M; Cuzin, F

1991-01-01

We have reported previously (1) two unexpected consequences of the microinjection into fertilized mouse eggs of a recombinant plasmid designated p12B1, carrying a 343 bp insert of non-repetitive mouse DNA. Injected at very low concentrations, this plasmid could be established as an extrachromosomal genetic element. When injected in greater concentration, an early arrest of embryonic development resulted. In the present work, we have studied this toxic effect in more detail by microinjecting short synthetic oligonucleotides with sequences from the mouse insert. Lethality was associated with the nucleotide sequence GTCACATG, identical with the CDEl element of yeast centromeres. Development of injected embryos was arrested between the one-cell and the early morula stages, with abnormal structures and DNA contents. Electrophoretic mobility shift and DNAse foot-printing assays demonstrated the binding of mouse nuclear protein(s) to the CDEl-like box. Base changes within the CDEl sequence prevented both the toxic effects in embryos and the formation of protein complex in vitro, suggesting that protein binding at such sites in chromosomal DNA plays an important role in early development. Images PMID:1766880

Metaphase to Anaphase (mat) Transition–Defective Mutants inCaenorhabditis elegans

PubMed Central

Golden, Andy; Sadler, Penny L.; Wallenfang, Matthew R.; Schumacher, Jill M.; Hamill, Danielle R.; Bates, Gayle; Bowerman, Bruce; Seydoux, Geraldine; Shakes, Diane C.

2000-01-01

The metaphase to anaphase transition is a critical stage of the eukaryotic cell cycle, and, thus, it is highly regulated. Errors during this transition can lead to chromosome segregation defects and death of the organism. In genetic screens for temperature-sensitive maternal effect embryonic lethal (Mel) mutants, we have identified 32 mutants in the nematode Caenorhabditis elegans in which fertilized embryos arrest as one-cell embryos. In these mutant embryos, the oocyte chromosomes arrest in metaphase of meiosis I without transitioning to anaphase or producing polar bodies. An additional block in M phase exit is evidenced by the failure to form pronuclei and the persistence of phosphohistone H3 and MPM-2 antibody staining. Spermatocyte meiosis is also perturbed; primary spermatocytes arrest in metaphase of meiosis I and fail to produce secondary spermatocytes. Analogous mitotic defects cause M phase delays in mitotic germline proliferation. We have named this class of mutants “mat” for metaphase to anaphase transition defective. These mutants, representing six different complementation groups, all map near genes that encode subunits of the anaphase promoting complex or cyclosome, and, here, we show that one of the genes, emb-27, encodes the C. elegans CDC16 ortholog. PMID:11134076

Orphaned female elephant social bonds reflect lack of access to mature adults.

PubMed

Goldenberg, Shifra Z; Wittemyer, George

2017-10-31

Compensatory social behavior in nonhuman animals following maternal loss has been documented, but understanding of how orphans allocate bonding to reconstruct their social networks is limited. Successful social integration may be critical to survival and reproduction for highly social species and, therefore, may be tied to population persistence. We examined the social partners involved in affiliative interactions of female orphans and non-orphans in an elephant population in Samburu, northern Kenya that experienced heightened adult mortality driven by drought and intense ivory poaching. We contrasted partners across different competitive contexts to gain insight to the influence of resource availability on social interactions. Though the number of partners did not differ between orphans and non-orphans, their types of social partners did. Orphans interacted with sisters and matriarchs less while feeding than did non-orphans, but otherwise their affiliates were similar. While resting under spatially concentrated shade, orphans had markedly less access to mature adults but affiliated instead with sisters, bulls, and age mates. Orphan propensity to strengthen bonds with non-dominant animals appears to offer routes to social integration following maternal loss, but lack of interaction with adult females suggests orphans may experience decreased resource access and associated fitness costs in this matriarchal society.

21 CFR 316.30 - Annual reports of holder of orphan-drug designation.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Annual reports of holder of orphan-drug... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ORPHAN DRUGS Designation of an Orphan Drug § 316.30 Annual reports of holder of orphan-drug designation. Within 14 months after the date on which a drug was designated...

Orphan status, HIV risk behavior, and mental health among adolescents in rural Kenya.

PubMed

Puffer, Eve S; Drabkin, Anya S; Stashko, Allison L; Broverman, Sherryl A; Ogwang-Odhiambo, Rose A; Sikkema, Kathleen J

2012-09-01

To examine orphan status, mental health, social support, and HIV risk among adolescents in rural Kenya. Randomly selected adolescents aged 10-18 years completed surveys assessing sexual activity, sex-related beliefs and self-efficacy, mental health, social support, caregiver-child communication, time since parental death, and economic resources. Analysis of covariance and regression analyses compared orphans and nonorphans; orphan status was tested as a moderator between well-being and HIV risk. Orphans reported poorer mental health, less social support, and fewer material resources. They did not differ from nonorphans on HIV risk indicators. Longer time since parental death was associated with poorer outcomes. In moderator analyses, emotional problems and poorer caregiver-youth communication were more strongly associated with lower sex-related self-efficacy for orphans. Orphans are at higher risk for psychosocial problems. These problems may affect orphans' self-efficacy for safer sex practices more than nonorphans. Decreased HIV risk could be one benefit of psychosocial interventions for orphans.

Migration, Household Configurations, and the Well-Being of Adolescent Orphans in Rwanda

PubMed Central

2014-01-01

This study uses data from the 2002 Rwandan census to situate the discourse on migration and orphan well-being within the context of the household. According to its findings, migrant orphans are less likely than non-migrant orphans to live in households with less favorable structural characteristics such as single-parent households. Significant differences are also found in the implied gains to living standards and schooling associated with migration among paternal, maternal, and double-orphans. However, the higher living standards and schooling attainment of orphan migrants relative to their non-migrant counterparts disappear within child-headed household contexts. More generally, the results indicate that the higher living standards of migrant orphans are in part driven by the fact that they mostly live in households with migrant household-heads or migrant spouses. Yet the analysis also suggests that orphans living within these contexts experience higher levels of intra-household discrimination in investments in their schooling, relative to their orphan counterparts who live in non-migrant households. PMID:25009364

Assessing the general health of diagnostic orphans using the Short Form Health Survey (SF-12v2): a latent variable modelling approach.

PubMed

McBride, Orla; Adamson, Gary; Bunting, Brendan P; McCann, Siobhan

2009-01-01

Research has demonstrated that diagnostic orphans (i.e. individuals who experience only one to two criteria of DSM-IV alcohol dependence) can encounter significant health problems. Using the SF-12v2, this study examined the general health functioning of alcohol users, and in particular, diagnostic orphans. Current drinkers (n = 26,913) in the National Epidemiologic Survey on Alcohol and Related Conditions were categorized into five diagnosis groups: no alcohol use disorder (no-AUD), one-criterion orphans, two-criterion orphans, alcohol abuse and alcohol dependence. Latent variable modelling was used to assess the associations between the physical and mental health factors of the SF-12v2 and the diagnosis groups and a variety of background variables. In terms of mental health, one-criterion orphans had significantly better health than two-criterion orphans and the dependence group, but poorer health than the no-AUD group. No significant differences were evident between the one-criterion orphan group and the alcohol abuse group. One-criterion orphans had significantly poorer physical health when compared to the no-AUD group. One- and two-criterion orphans did not differ in relation to physical health. Consistent with previous research, diagnostic orphans in the current study appear to have experienced clinically relevant symptoms of alcohol dependence. The current findings suggest that diagnostic orphans may form part of an alcohol use disorders spectrum severity.

The extent of community and public support available to families caring for orphans in Malawi.

PubMed

Kidman, Rachel; Heymann, S Jody

2009-04-01

There are an estimated 15 million AIDS orphans worldwide. Families play an important role in safeguarding orphans, but they may be increasingly compromised by the HIV/AIDS epidemic. The international aid community has recognized the need to help families continue caring for orphaned children by strengthening their safety nets. Before we build new structures, however, we need to know the extent to which community and public safety nets already provide support to families with orphans. To address this gap, we analyzed nationally representative data from 27,495 children in the 2004-2005 Malawi Integrated Household Survey. We found that communities commonly assisted orphan households through private transfers; organized responses to the orphan crisis were far less frequent. Friends and relatives provided assistance to over 75% of orphan households through private gifts, but the value of such support was relatively low. Over 40% of orphans lived in a community with support groups for the chronically ill and approximately a third of these communities provided services specifically for orphans and other vulnerable children. Public programs, which form a final safety net for vulnerable households, were more widespread. Free/subsidized agricultural inputs and food were the most commonly used public safety nets by children's households in the past year (44 and 13%, respectively), and households with orphans were more likely to be beneficiaries. Malawi is poised to drastically expand safety nets to orphans and their families, and these findings provide an important foundation for this process.

Zinc oxide nanoparticle toxicity in embryonic zebrafish: Mitigation with different natural organic matter.

PubMed

Kteeba, Shimaa M; El-Adawi, Hala I; El-Rayis, Osman A; El-Ghobashy, Ahmed E; Schuld, Jessica L; Svoboda, Kurt R; Guo, Laodong

2017-11-01

Exposure experiments were conducted to evaluate the influence of dissolved organic matter (DOM) on the toxicity of ZnO-NPs (10-30 nm) and dissolved Zn at sub-lethal doses (50 and 5 ppm, respectively) to zebrafish (Danio rerio). Humic acid, alginic acid, bovine serum albumin and various natural DOM isolated from rivers as the Milwaukee River-WI (NOMW), Yukon River-AK (NOMA) and Suwannee River-GA DOM (NOMS) were used to represent humic substances (HA), carbohydrates (CHO), proteins (PTN), and natural organic matter (NOM), respectively. Initial experiments were carried out to confirm the toxic effect of ZnO-NPs at 50 ppm, followed by mitigation experiments with different types and concentrations of DOM (0.4-40 mg-C/L). Compared to 0% hatch of 50 ppm ZnO-NPs exposed embryos at 72 h post fertilization (hpf), NOMS, NOMW and HA had the best mitigative effects on hatching (53-65%), followed by NOMA, CHO and PTN (19-35%); demonstrating that the mitigation effects on ZnO-NPs toxicity were related to DOM's quantity and composition. At 96 hpf, 20% of embryos exposed to 50 ppm ZnO-NPs hatched, 100% of embryos reared in embryo medium hatched, and close to 100% of the embryos hatched upon mitigation, except for those mitigated with PTN which had less effect. Dissolved Zn (5 ppm) also exhibited the same toxicity on embryos as ZnO-NPs (50 ppm). However, in the presence of HA, NOM and CHO, the hatching rates at 72 and 96 hpf increased significantly compared to 5% hatch without DOM. The overall mitigation effects produced by DOM followed the order of HA ≥ NOMS > NOM (A&W) > CHO > PTN, although specific mitigation effects varied with DOM concentration and functionalities. Our results also indicate that the toxicity of ZnO-NPs to embryos was mostly derived from NPs although dissolved Zn released from ZnO-NPs also interacted with embryos, affecting hatching, but to a less extent. Copyright © 2017 Elsevier Ltd. All rights reserved.

21 CFR 316.23 - Timing of requests for orphan-drug designation; designation of already approved drugs.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) A sponsor may request orphan-drug designation at any time in the drug development process prior to... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Timing of requests for orphan-drug designation..., DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE ORPHAN DRUGS Designation of an Orphan...

Cultural practices and sexual risk behaviour among adolescent orphans and non-orphans: a qualitative study on perceptions from a community in western Kenya

PubMed Central

2014-01-01

Background This study explored community perceptions of cultural beliefs and practices that may increase sexual risk behaviour of adolescents, to understand more about meaning they hold within the culture and how they expose adolescent orphans and non-orphans to higher risks in a high HIV and teenage pregnancy prevalence context. Methods Using a qualitative descriptive cross-sectional design 14 focus group discussions were conducted with 78 adolescents and 68 parents/guardians purposively selected to represent their communities. Thirteen key informant interviews were also conducted with community leaders, health care and child welfare workers, and adolescents who were also selected purposively. The two methods were used to explore how cultural beliefs and practices predispose adolescent orphans and non- orphans to risky sexual behaviours. Data were analysed through line-by-line coding, grouped into families and retrieved as themes and sub-themes. Results Identified cultural practices that predisposed adolescents orphans and non-orphans to risky sexual behaviours included: adolescent sleeping arrangements, funeral ceremonies, replacing a deceased married daughter with her younger sister in marriage, widow inheritance among boys, early marriage among girls, and preference for boys/sons. Cultural risks perceived to equally affect both orphans and non-orphans were sleeping arrangements, funeral ceremonies, and sister replacement. Factors associated more with orphans than non-orphans were widow inheritance among boys and a preference for boy over girl children. Conclusions Adolescent sexual risk reduction programs should be developed considering the specific cultural context, using strategies that empower communities to challenge the widely accepted cultural norms that may predispose young people in general to sexual risks while targeting those that unequally influence orphans. PMID:24467940

Cultural practices and sexual risk behaviour among adolescent orphans and non-orphans: a qualitative study on perceptions from a community in Western Kenya.

PubMed

Juma, Milka; Askew, Ian; Alaii, Jane; Bartholomew, L Kay; van den Borne, Bart

2014-01-27

This study explored community perceptions of cultural beliefs and practices that may increase sexual risk behaviour of adolescents, to understand more about meaning they hold within the culture and how they expose adolescent orphans and non-orphans to higher risks in a high HIV and teenage pregnancy prevalence context. Using a qualitative descriptive cross-sectional design 14 focus group discussions were conducted with 78 adolescents and 68 parents/guardians purposively selected to represent their communities. Thirteen key informant interviews were also conducted with community leaders, health care and child welfare workers, and adolescents who were also selected purposively. The two methods were used to explore how cultural beliefs and practices predispose adolescent orphans and non- orphans to risky sexual behaviours. Data were analysed through line-by-line coding, grouped into families and retrieved as themes and sub-themes. Identified cultural practices that predisposed adolescents orphans and non-orphans to risky sexual behaviours included: adolescent sleeping arrangements, funeral ceremonies, replacing a deceased married daughter with her younger sister in marriage, widow inheritance among boys, early marriage among girls, and preference for boys/sons. Cultural risks perceived to equally affect both orphans and non-orphans were sleeping arrangements, funeral ceremonies, and sister replacement. Factors associated more with orphans than non-orphans were widow inheritance among boys and a preference for boy over girl children. Adolescent sexual risk reduction programs should be developed considering the specific cultural context, using strategies that empower communities to challenge the widely accepted cultural norms that may predispose young people in general to sexual risks while targeting those that unequally influence orphans.

HIV seroprevalence among orphaned and homeless youth: no place like home.

PubMed

Hillis, Susan D; Zapata, Lauren; Robbins, Cheryl L; Kissin, Dmitry M; Skipalska, Halyna; Yorick, Roman; Finnerty, Erin; Marchbanks, Polly A; Jamieson, Denise J

2012-01-02

We evaluated the combined influences of orphaned status and homelessness on HIV seroprevalence and risk among street-involved Ukrainian youth in 2008. Systematic, multicity, community-based, cross-sectional assessment. Time-location sampling was used to identify eligible youth aged 15-24 after city-wide mapping of 91 sites where street-involved youth gathered in Odessa, Kiev, and Donetsk. Universal sampling identified 961 youth in 74 randomly selected sites; 97% consented. Youth reporting one or both parents dead were classified as orphaned; those without a stable residence or sleeping outside their residence at least two nights per week were classified as homeless. Trained staff provided HIV counseling and rapid testing via mobile vans. Adjusted odds ratios (AORs) were calculated using logistic regression, accounting for intracluster homogeneity. We found 32% (300 of 929) were both orphaned and homeless; 48% either (but not both) homeless [37% (343 of 929)] or orphaned [11% (104 of 929)]; and [20% (182 of 929)] neither orphaned nor homeless. HIV seroprevalences were 7% for neither orphaned/homeless; 16 and 17%, respectively, for either orphaned/homeless; 28% for both orphaned/homeless (P for trend <0.0001). AORs for HIV infection were 1 for neither; 2.3 and 2.4 for either homeless [95% confidence interval (CI) 1.7-2.9] or orphaned (CI 1.8-3.3); 3.3 for both orphaned/homeless (CI 2.3-4.4). Ever-use of injection drugs increased from 15 to 32 to 48% for those who neither, either, or both orphaned and homeless, respectively (P for trend <0.0001). One of four youths who were both homeless and orphaned was HIV-infected; these youths were significantly more likely to be HIV infected and to report injection drug use than those with adequate housing and living parents.

Impact of orphan drugs on Latvian budget.

PubMed

Logviss, Konstantins; Krievins, Dainis; Purvina, Santa

2016-05-11

Number of orphan medicinal products on the market and number of rare disease patients, taking these usually expensive products, are increasing. As a result, budget impact of orphan drugs is growing. This factor, along with the cost-effectiveness of orphan drugs, is often considered in the reimbursement decisions, directly affecting accessibility of rare disease therapies. The current study aims to assess the budget impact of orphan drugs in Latvia. Our study covered a 5-year period, from 2010 to 2014. Impact of orphan drugs on Latvian budget was estimated from the National Health Service's perspective. It was calculated in absolute values and relative to total pharmaceutical market and total drug reimbursement budget. A literature review was performed for comparison with other European countries. Orphan drug annual expenditure ranged between EUR 2.065 and 3.065 million, with total 5-year expenditure EUR 12.467 million. It constituted, on average, 0.84 % of total pharmaceutical market and 2.14 % of total drug reimbursement budget, respectively. Average annual per patient expenditures varied widely, from EUR 1 534 to EUR 580 952. The most costly treatment was enzyme replacement therapy (Elaprase) for MPS II. Glivec had the highest share (34 %) of the total orphan drug expenditure. Oncological drugs represented more than a half of the total orphan drug expenditure, followed by drugs for metabolic and endocrine conditions and medicines for cardiopulmonary diseases. Three indications: Ph+ CML, MPS II, and PAH accounted for nearly 90 % of the total orphan drug expenditure. Budget impact of orphan drugs in Latvia is very small. It increased slightly over a period of five years, due to the slight increase in the number of patients and the number of orphan drugs reimbursed. Current Latvian drug reimbursement system is not sufficient for most orphan drugs.

Posttraumatic stress symptoms among adults caring for orphaned children in HIV-endemic South Africa.

PubMed

Kuo, Caroline; Reddy, Madhavi K; Operario, Don; Cluver, Lucie; Stein, Dan J

2013-06-01

There is growing evidence that mental health is a significant issue among families affected by AIDS-related parental deaths. The current study examined posttraumatic stress symptoms and identified risk factors among adults caring for AIDS-orphaned and other-orphaned children in an HIV-endemic South African community. A representative community sample of adults caring for children (N = 1,599) was recruited from Umlazi Township. Of the 116 participants who reported that a traumatic event was still bothering them, 19 % reported clinically significant posttraumatic stress symptoms. Of the 116 participants, caregivers of AIDS-orphaned and other-orphaned children were significantly more likely to meet threshold criteria for PTSD (28 %) compared to caregivers of non-orphaned children (10 %). Household receipt of an old age pension was identified as a possible protective factor for PTSD symptoms among caregivers of orphaned children. Services are needed to address PTSD symptoms among caregivers of orphaned children.

Posttraumatic Stress Symptoms among Adults Caring for Orphaned Children in HIV-endemic South Africa

PubMed Central

Kuo, Caroline; Reddy, Madhavi K.; Operario, Don; Cluver, Lucie; Stein, Dan J.

2013-01-01

There is growing evidence that mental health is a significant issue among families affected by AIDS-related parental deaths. The current study examined posttraumatic stress symptoms and identified risk factors among adults caring for AIDS-orphaned and other-orphaned children in an HIV-endemic South African community. A representative community sample of adults caring for children (N = 1,599) was recruited from Umlazi Township. Of the 116 participants who reported that a traumatic event was still bothering them, 19% reported clinically significant posttraumatic stress symptoms. Of the 116 participants, caregivers of AIDS-orphaned and other-orphaned children were significantly more likely to meet threshold criteria for PTSD (28%) compared to caregivers of non-orphaned children (10%). Household receipt of an old age pension was identified as a possible protective factor for PTSD symptoms among caregivers of orphaned children. Services are needed to address PTSD symptoms among caregivers of orphaned children. PMID:23539187

Points to consider: efficacy and safety evaluations in the clinical development of ultra-orphan drugs.

PubMed

Maeda, Kojiro; Kaneko, Masayuki; Narukawa, Mamoru; Arato, Teruyo

2017-08-23

The unmet medical needs of individuals with very rare diseases are high. The clinical trial designs and evaluation methods used for 'regular' drugs are not applicable in the clinical development of ultra-orphan drugs (<1000 patients) in many cases. In order to improve the clinical development of ultra-orphan drugs, we examined several points regarding the efficient evaluations of drug efficacy and safety that could be conducted even with very small sample sizes, based on the review reports of orphan drugs approved in Japan. The clinical data packages of 43 ultra-orphan drugs approved in Japan from January 2001 to December 2014 were investigated. Japanese clinical trial data were not included in the clinical data package for eight ultra-orphan drugs, and non-Japanese clinical trial data were included for six of these eight drug. Japanese supportive data that included retrospective studies, published literature, clinical research and Japanese survey results were clinical data package attachments in 22 of the 43 ultra-orphan drugs. Multinational trials were conducted for three ultra-orphan drugs. More than two randomized controlled trials (RCTs) were conducted for only 11 of the 43 ultra-orphan drugs. The smaller the number of patients, the greater the proportion of forced titration and optional titration trials were conducted. Extension trials were carried out for enzyme preparations and monoclonal antibodies with high ratio. Post-marketing surveillance of all patients was required in 36 of the 43 ultra-orphan drugs. For ultra-orphan drugs, clinical endpoints were used as the primary efficacy endpoint of the pivotal trial only for two drugs. The control groups in RCTs were classified as follows: placebo groups different dosage groups, and active controls groups. Sample sizes have been determined on the basis of feasibility for some ultra-orphan drugs. We provide "Draft Guidance on the Clinical Development of Ultra-Orphan Drugs" based on this research. The development of ultra-orphan drugs requires various arrangements regarding evidence collection, data sources and the clinical trial design. We expect that this draft guidance is useful for ultra-orphan drugs developments in future.

Nutritional status, psychological well-being and the quality of life of AIDS orphans in rural Henan Province, China.

PubMed

He, Zhonghu; Ji, Chengye

2007-10-01

To assess the influence of orphanhood due to AIDS on children's nutritional status, psychological well-being and life quality, and to explore appropriate intervention strategies in China. In 2005, 186 children aged 8-15 years (93 AIDS orphans and 93 non-orphans) from a rural area of Henan Province were surveyed in a cross-sectional and matched pairs study on nutritional status, psychological health and life quality. We found no compelling evidence for poorer nutritional status in orphans. The nutritional status of both orphans and non-orphans was extremely poor according to the prevalence of stunting, underweight, wasting and anaemia. Depression, low self-esteem and lower quality of life were more frequent in orphans. These differences mainly existed in boys' groups. No significant differences were found between paternal, maternal and double orphans, or orphans in orphanages or extended families. Regression analysis revealed that orphanhood leads to low self-esteem and more depression which contributes to lower quality of life and mediates the association between orphanhood and quality of life. The high prevalence of poor nutritional status indicates that basic material needs of children, including AIDS orphans, are not met in rural China. Psychological problems were prominent among orphans and had become the most important contributor of lower life quality. Boys were at least as vulnerable as girls. The living conditions of all children in rural China must be improved; school-based care and support are crucial and would be a cost-effective way to improve the overall life quality of AIDS orphans.

Is orphan drug status beneficial to tropical disease control? Comparison of the American and future European orphan drug acts.

PubMed

Trouiller, P; Battistella, C; Pinel, J; Pecoul, B

1999-06-01

OBJECTIVES To quantify past outcomes of tropical pharmacology research and development (R & D) and to assess past benefits of the American orphan drug act and potential benefits of the future European orphan drug regulation on tropical diseases. This paper presents two analyses: a 1983-97 retrospective study of the United States Orphan Drug Act concerning rare diseases and a prospective study of the European Proposal for a Regulation Concerning Orphan Drugs and its possible impact on tropical diseases. Different programmes have in the past tried to stimulate R & D in this area, but results remain limited. Of 1450 new chemical entities marketed between 1972 and 1997, 13 were specifically for tropical diseases and considered as essential drugs. Between 1983 & 1997, the US Orphan Drug Act approved 837 drugs and marketing of 152 new molecular entities (NMEs). Three NMEs have been designated for malaria and human African trypanosomiasis. Seven others, already commonly used in tropical diseases, received either orphan designation or an orphan approval for another indication. Pharmaceutical companies benefit from the US framework only when the US market exclusivity clause was applicable. Future European orphan drug regulation appears to be similar to the US Orphan Drug Act. CONCLUSION The orphan drug programmes relating to rare diseases have met with some success. Considering tropical diseases rare diseases seems inadequate to boost pharmaceutical R & D. However, some provisions of the European text may be relevant to tropical diseases, admitting the need for a more specific rule for evaluations of this kind of drug and recognizing the existence of 'diseases of exception'.

Some Numbers behind Canada's Decision to Adopt an Orphan Drug Policy: US Orphan Drug Approvals in Canada, 1997-2012.

PubMed

Herder, Matthew; Krahn, Timothy Mark

2016-05-01

We examined whether access to US-approved orphan drugs in Canada has changed between 1997 (when Canada chose not to adopt an orphan drug policy) and 2012 (when Canada reversed its policy decision). Specifically, we looked at two dimensions of access to US-approved orphan drugs in Canada: (1) regulatory access; and (2) temporal access. Whereas only 63% of US-approved orphan drugs were granted regulatory approval in 1997, we found that regulatory access to US-approved orphan drugs in Canada increased to 74% between 1997 and 2012. However, temporal access to orphan drugs is slower in Canada: in a head-on comparison of 40 matched drugs, only two were submitted and four were approved first in Canada; moreover, the mean review time in Canada (423 days) was longer than that in the US (mean = 341 days), a statistically significant difference (t[39] = 2.04, p = 0.048). These results raise questions about what motivated Canada's apparent shift in orphan drug policy. Copyright © 2016 Longwoods Publishing.

Orphan drugs: the regulatory environment.

PubMed

Franco, Pedro

2013-02-01

The definition of a rare disease is not universal and depends on the legislation and policies adopted by each region or country. The main objective of this article is to describe and discuss the legal framework and the regulatory environment of orphan drugs worldwide. Some reflections and discussions on the need for specific orphan drug legislation or policies are described at length. Furthermore, some aspects of the history of each region in respect of the orphan drug legislation evolution are outlined. This article describes and compares the orphan drug legislation or policies of the following countries or regions: United Sates of America (US), European Union (EU), Japan, Australia, Singapore, Taiwan and Canada. The incentives described in the orphan drug legislations or policies, the criteria for designation of orphan status and the authorisation process of an orphan drug are also described and compared. The legislations and policies are to some extent similar but not the same. It is important to understand the main differences among all available legislative systems to improve the international collaboration in the field of orphan drugs and rare diseases. Copyright © 2012 Elsevier Ltd. All rights reserved.

Care arrangements, grief and psychological problems among children orphaned by AIDS in China.

PubMed

Zhao, G; Li, X; Fang, X; Zhao, J; Yang, H; Stanton, B

2007-10-01

The China Ministry of Health has estimated that there are at least 100,000 AIDS orphans in China. The UNICEF China Office estimates that between 150,000 and 250,000 additional children will be orphaned by AIDS over the next five years. However, limited data are available regarding the sociodemographic characteristics, care arrangements, barriers to appropriate grief resolution and psychological problems among AIDS orphans in China. In this article, we review secondary data and reports from scientific literature, government, non-governmental organisations and public media regarding children orphaned by AIDS in China to address their living situation, bereavement process and psychological problems. Our review suggests that AIDS orphans in China are living in a stressful environment, with many orphans struggling with psychological problems and unmet basic needs such as food, shelter, education and medical care. Based on our review, we suggest that future studies should address the psychosocial needs of AIDS orphans in China and develop health promotion programmes to mitigate the negative impact of parental death on the physical and psychosocial well-being of these orphans.

Care arrangement, grief, and psychological problems among children orphaned by AIDS in China

PubMed Central

Zhao, Guoxiang; Li, Xiaoming; Fang, Xiaoyi; Zhao, Junfeng; Yang, Hongmei; Stanton, Bonita

2007-01-01

The China Ministry of Health has estimated that there are at least 100,000 AIDS orphans in China. The UNICEF China Office estimates that between 150,000 and 250,000 additional children will be orphaned by AIDS over the next five years. However, limited data are available regarding the socio-demographic characteristics, care arrangement, barriers to appropriate grief resolution and psychological problems among AIDS orphans in China. In this article, we review secondary data and reports from scientific literature, government, non-governmental organizations, and public media regarding children orphaned by AIDS in China to address their living situation, bereavement process, and psychological problems. Our review suggests that AIDS orphans in China are living in a stressful environment with many orphans struggling with psychological problems and unmet basic needs such as food, shelter, education, and medical care. Based on our review, we suggest that future studies should address the psychosocial needs of AIDS orphans in China and develop health promotion programs to mitigate the negative impact of parental death on the physical and psychosocial well-being of these orphans. PMID:18058390

Fumitoxins, new mycotoxins from Aspergillus fumigatus Fres.

PubMed

Debeaupuis, J P; Lafont, P

1978-07-01

Extracts of cultures of Aspergillus fumigatus isolated from silage were lethal to chicken embryos. Using this test and thin-layer chromatography, four UV-absorbing toxins, designated as fumitoxins A, B, C and D, were isolated. Analysis and mass spectrometry of crystallized fumitoxin A, the most abundant in the extract, established its molecular formula to be C31H42O8. Infrared, UV spectroscopy, and chemical reactions suggested that fumitoxin A is a steroid. Fumitoxins appear to be clearly different from the previously described toxins recognized in A. fumigatus.

Fumitoxins, new mycotoxins from Aspergillus fumigatus Fres.

PubMed Central

Debeaupuis, J P; Lafont, P

1978-01-01

Extracts of cultures of Aspergillus fumigatus isolated from silage were lethal to chicken embryos. Using this test and thin-layer chromatography, four UV-absorbing toxins, designated as fumitoxins A, B, C and D, were isolated. Analysis and mass spectrometry of crystallized fumitoxin A, the most abundant in the extract, established its molecular formula to be C31H42O8. Infrared, UV spectroscopy, and chemical reactions suggested that fumitoxin A is a steroid. Fumitoxins appear to be clearly different from the previously described toxins recognized in A. fumigatus. PMID:358921

Finding Sequences for over 270 Orphan Enzymes

PubMed Central

Shearer, Alexander G.; Altman, Tomer; Rhee, Christine D.

2014-01-01

Despite advances in sequencing technology, there are still significant numbers of well-characterized enzymatic activities for which there are no known associated sequences. These ‘orphan enzymes’ represent glaring holes in our biological understanding, and it is a top priority to reunite them with their coding sequences. Here we report a methodology for resolving orphan enzymes through a combination of database search and literature review. Using this method we were able to reconnect over 270 orphan enzymes with their corresponding sequence. This success points toward how we can systematically eliminate the remaining orphan enzymes and prevent the introduction of future orphan enzymes. PMID:24826896

Orphan drug: Development trends and strategies

PubMed Central

Sharma, Aarti; Jacob, Abraham; Tandon, Manas; Kumar, Dushyant

2010-01-01

The growth of pharma industries has slowed in recent years because of various reasons such as patent expiries, generic competition, drying pipelines, and increasingly stringent regulatory guidelines. Many blockbuster drugs will loose their exclusivity in next 5 years. Therefore, the current economic situation plus the huge generic competition shifted the focus of pharmaceutical companies from the essential medicines to the new business model — niche busters, also called orphan drugs. Orphan drugs may help pharma companies to reduce the impact of revenue loss caused by patent expiries of blockbuster drugs. The new business model of orphan drugs could offer an integrated healthcare solution that enables pharma companies to develop newer areas of therapeutics, diagnosis, treatment, monitoring, and patient support. Incentives for drug development provided by governments, as well as support from the FDA and EU Commission in special protocols, are a further boost for the companies developing orphan drugs. Although there may still be challenges ahead for the pharmaceutical industry, orphan drugs seem to offer the key to recovery and stability within the market. In our study, we have compared the policies and orphan drug incentives worldwide alongwith the challenges faced by the pharmaceutical companies. Recent developments are seen in orphan drug approval, the various drugs in orphan drug pipeline, and the future prospectives for orphan drugs and diseases. PMID:21180460

A comparative study of European rare disease and orphan drug markets.

PubMed

Denis, Alain; Mergaert, Lut; Fostier, Christel; Cleemput, Irina; Simoens, Steven

2010-10-01

This article aims to compare regulatory aspects of rare disease and orphan drug markets in Belgium, France, Italy, the Netherlands, Sweden and the United Kingdom. Information was derived from the international literature, analysis of legal texts, and a survey completed by national experts. These countries adopted varying approaches towards regulating rare disease and orphan drug markets and, hence, the availability, pricing and reimbursement of orphan drugs vary between countries. Strategies to keep down prices include public procurement in Sweden, profit controls in the United Kingdom, and price comparisons with other countries. To gain reimbursement, the cost-effectiveness and/or budget impact of orphan drugs is considered in some countries. Other societal considerations, such as whether the drug treats a life-threatening disease, are sometimes taken into account. Extensive government intervention exists in rare disease and orphan drug markets in the countries studied. Our recommendations are to define priorities for research on rare diseases and orphan drugs at the European level, to set up disease and patient registries with a view to investigating the long-term effectiveness and cost-effectiveness of orphan drugs, to assess the profitability of orphan drugs, and to take into account societal considerations when evaluating orphan drugs. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Orphan drugs for rare diseases: is it time to revisit their special market access status?

PubMed

Simoens, Steven; Cassiman, David; Dooms, Marc; Picavet, Eline

2012-07-30

Orphan drugs are intended for diseases with a very low prevalence, and many countries have implemented legislation to support market access of orphan drugs. We argue that it is time to revisit the special market access status of orphan drugs. Indeed, evidence suggests that there is no societal preference for treating rare diseases. Although society appears to assign a greater value to severity of disease, this criterion is equally relevant to many common diseases. Furthermore, the criterion of equity in access to treatment, which underpins orphan drug legislation, puts more value on health improvement in rare diseases than in common diseases and implies that population health is not maximized. Finally, incentives for the development, pricing and reimbursement of orphan drugs have created market failures, including monopolistic prices and the artificial creation of rare diseases. We argue that, instead of awarding special market access status to orphan drugs, there is scope to optimize research and development (R&D) of orphan drugs and to control prices of orphan drugs by means of, for example, patent auctions, advance purchase commitments, pay-as-you-go schemes and dose-modification studies. Governments should consider carefully the right incentive strategy for R&D of orphan drugs in rare diseases.

Assertiveness and Attitudes of HIV/AIDS Orphaned Girls Towards Education in Kampala (Uganda).

PubMed

Kitara, David Lagoro; Amongin, Hellen Christine; Oonyu, Joseph C; Baguma, Peter K

2013-08-09

Whereas HIV/AIDS prevalence has been declining in Uganda from 30% to less than 10% in the last 2 decades, the number of HIV/AIDS orphaned girls in secondary schools is still high and girl children have tended to carry the heaviest burdens of family responsibilities thereby adversely affecting their assertiveness and attitudes towards education. Assertiveness is a critical life skill that enables a person to state an opinion, claim a right, or establish authority and it is important to improve attitude towards education. This study examined the relationship between assertiveness and attitude towards education of HIV/AIDS orphaned and non-orphaned adolescent school girls in Kampala. The California Psychological Inventory (CPI) Dominance (Do) Assertiveness Scale and the Attitude Scale were administered to 225 students consecutively selected from 6 secondary schools in Kampala. HIV/AIDS Orphaned girls had lower levels of assertiveness and most had a negative attitude towards education compared to non-orphaned girls. Girls orphaned to HIV/AIDS were less assertive compared to those orphaned by other causes. There was a positive relationship between assertiveness and attitude towards education among orphaned adolescent secondary school girls in Kampala. Girls orphaned to HIV/AIDS were less assertive compared to other school girls and have a poor attitude towards education.

Barriers and incentives to orphan care in a time of AIDS and economic crisis: a cross-sectional survey of caregivers in rural Zimbabwe.

PubMed

Howard, Brian H; Phillips, Carl V; Matinhure, Nelia; Goodman, Karen J; McCurdy, Sheryl A; Johnson, Cary A

2006-02-09

Africa is in an orphan-care crisis. In Zimbabwe, where one-fourth of adults are HIV-positive and one-fifth of children are orphans, AIDS and economic decline are straining society's ability to care for orphans within their extended families. Lack of stable care is putting thousands of children at heightened risk of malnourishment, emotional underdevelopment, illiteracy, poverty, sexual exploitation, and HIV infection, endangering the future health of the society they are expected to sustain. To explore barriers and possible incentives to orphan care, a quantitative cross-sectional survey in rural eastern Zimbabwe asked 371 adults caring for children, including 212 caring for double orphans, about their well-being, needs, resources, and perceptions and experiences of orphan care. Survey responses indicate that: 1) foster caregivers are disproportionately female, older, poor, and without a spouse; 2) 98% of non-foster caregivers are willing to foster orphans, many from outside their kinship network; 3) poverty is the primary barrier to fostering; 4) financial, physical, and emotional stress levels are high among current and potential fosterers; 5) financial need may be greatest in single-orphan AIDS-impoverished households; and 6) struggling families lack external support. Incentives for sustainable orphan care should focus on financial assistance, starting with free schooling, and development of community mechanisms to identify and support children in need, to evaluate and strengthen families' capacity to provide orphan care, and to initiate and support placement outside the family when necessary.

Optimised management of orphan wastes in the UK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doudou, Slimane; McTeer, Jennifer; Wickham, Stephen

2013-07-01

Orphan wastes have properties preventing them from being managed according to existing or currently planned management routes, or lack characterisation so that their management is uncertain. The identification of new management opportunities for orphan wastes could realise significant benefits by reducing the number of processing facilities required, reducing waste volumes, reducing hazard or leading to the development of centres of excellence for the processing of certain types of orphan wastes. Information on the characteristics of orphan waste existing at nuclear licensed sites across the UK has been collated and a database developed to act as a repository for the informationmore » gathered. The database provides a capability to analyse the data and to explore possible treatment technologies for each orphan waste type. Thirty five distinct orphan waste types have been defined and possible treatment options considered. Treatment technologies (including chemical, high temperature, immobilisation and physical technologies) that could be applied to one or more of the generic orphan waste streams have been identified. Wiring diagrams have been used to highlight the waste treatment / lifecycle management options that are available for each of the generic orphan groups as well as identifying areas for further research and development. This work has identified the potential for optimising the management of orphan wastes in a number of areas, and many potential opportunities were identified. Such opportunities could be investigated by waste managers at waste producing nuclear sites, to facilitate the development of new management routes for orphan wastes. (authors)« less

Cytogenetic studies following high dosage paternal irradiation in the mealy bug, Planococcus citri: I. Cytology of X1 embryos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chandra, H. Sharat

1963-01-01

In the mealy bug, Planococcus citri, following high dosage paternal irradiation (60,000 to 120,000 rep), the survivors are mostly female (about 30 to 40% of the unirradiated control value) whereas very few males survive (about 5% of control value). After lower doses of paternal irradiation (P.I.), however, few or no females survive while the normal number of males (never less than the control value) survive. The females developing after high dosage P.I. are gynogenetic and are triploid or diploid or 3N/2N or 2N/N mosaics. The cytology of X 1 embryos following 90,000 rep is described in comparison with data frommore » embryos following lower doses (8,000 r) of P.I. and unirradiated controls, to illustrate the chromosomal mechanisms leading to the production of gynogenetic females and the probable reasons for lethality of X 1 males after heavy P.I. It has been shown that triploid females stem from a fusion nucleus of the first and second polar bodies. This triploid polar nucleus, which normally participates in the formation of a polyploid sector in the young embryo, undertakes a successful embryogeny in many embryos when the zygote nucleus is unable to do so because of the heavily damaged paternal complement of chromosomes. Since the chromosomes are characterized by holokinetic activity, the irradiated paternal set manages to divide with the maternal complement but did not always segregate as successfully. Restitution divisions of the zygotic nuclei result in haploid, hyperhaploid, diploid and polyploid nuclei. Most of the diploid gynogenetic females probably originate from diploid nuclei of zygotic origin although it is possible that a few diploid females and the 2N/N mosaic females develop from polar bodies.« less

CYTOGENETIC STUDIES FOLLOWING HIGH DOSAGE PATERNAL IRRADIATION IN THE MEALY BUG PLANOCOCCUS CITRI. I. CYTOLOGY OF X$sup 1$ EMBRYOS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chandra, H.S.

1963-06-01

In cultures of the mealy bug, following high dosage paternal Co/sup 60/ gamma irradiation (60000--120000 rep), the survivors are mostly female (an increase of 30 to 40% above the unirradiated control value) whereas very few males survive (about 5% of control value). After lower doses of paternal irradiation (PI), however, few or no females survive while the normal number of males survive. The females developing after high dosage PI are gynogenetic and are triploid or diploid, or 3N/2N or 2N/N mosaics. The cytology of X/sub 1/ embryos following 90000 rep is described and compared with that of embryos following lowermore » doses (8000 r) of PI and unirradiated controls, to illustrate the chromosomal mechanisms leading to the production of gynogenetic females and the probable reasons for lethality of X/sub 1/ males after heavy PI. It was shown that triploid females stem from a fusion nucleus of the first and second polar bodies. This triploid polar nucleus, which normally participates in the formation of a polyploid sector in the yourg embryo, undertakes successful embryogeny in many embryos when the zygote nucleus is unable to do so because of the heavily damaged paternal complement of chromosomes. Since the chromosomes are characterized by holokinetic activity, the irradiated paternal set mandsges to divide with the matennal complement but does not always segregate as successfully. Restitution divisions of the zygotic nuclei result in haploid, hyperhaploid, diploid, and polyploid nuclei. Most of the diploid gynogenetic females probably originate from diploid nuclei of zygotic origin, although it is possible that a few diploid females and the 2N/N mosaic females develop from polar bodies. (BBB)« less

Amphibian embryos as a biological test for environmental pollutants in leachates, industrial effluents, surface and ground water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herkovits, J.; Perez-Coll, C.S.; Herkovits, F.D.

1995-12-31

Test of early life stages are very sensitive to toxic effects and moreover a good predictive correlation between embryo-larval survival and independent ecological parameters such as species richness and diversity have been established. The main purpose of this preliminary study is to report that Bufo arenarum embryos are very sensitive to contaminants from a variety of sources such as leachates, industrial effluents, surface and ground water. The toxicity of 30 samples (five from each category plus controls of surface and ground water from reference places) was evaluated during a 14 day renewal toxicity test at 20 C, conducted with 10more » embryos (by triplicate) from stage 23--25 onwards using six concentrations (V/V) of each sample of Holtfreter`s solution. For industrial effluents and leachates the results range from a concentration of 0.6% resulting in 24hs LC100 up to a sample which exert 20% of lethality after 14 days of treatment. The survival of controls and in samples from reference places was over 90% for 7 days and over 80% for 14 days. The results with Bufo arenarum embryos confirm that a 7 day Short-term Chronic Toxicity Test is appropriate for toxicity screening of industrial effluents (as it was established by EPA for whole effluent toxicity test for aquatic life protection performed with other species) as well as for leachates. On the other hand, for freshwater (surface and ground), it is convenient to extend the exposure period until 14 days in order to record situations of low, but significant levels of toxicity, which could be of particular value for surface as well as ground water quality criteria.« less

Amino-modified polystyrene nanoparticles affect signalling pathways of the sea urchin (Paracentrotus lividus) embryos.

PubMed

Pinsino, Annalisa; Bergami, Elisa; Della Torre, Camilla; Vannuccini, Maria Luisa; Addis, Piero; Secci, Marco; Dawson, Kenneth A; Matranga, Valeria; Corsi, Ilaria

2017-03-01

Polystyrene nanoparticles have been shown to pose serious risk to marine organisms including sea urchin embryos based on their surface properties and consequently behaviour in natural sea water. The aim of this study is to investigate the toxicity pathways of amino polystyrene nanoparticles (PS-NH 2 , 50 nm) in Paracentrotus lividus embryos in terms of development and signalling at both protein and gene levels. Two sub-lethal concentrations of 3 and 4 μg/mL of PS-NH 2 were used to expose sea urchin embryos in natural sea water (PS-NH 2 as aggregates of 143 ± 5 nm). At 24 and 48 h post-fertilisation (hpf) embryonic development was monitored and variations in the levels of key proteins involved in stress response and development (Hsp70, Hsp60, MnSOD, Phospho-p38 Mapk) as well as the modulation of target genes (Pl-Hsp70, Pl-Hsp60, Pl-Cytochrome b, Pl-p38 Mapk, Pl-Caspase 8, Pl-Univin) were measured. At 48 hpf various striking teratogenic effects were observed such as the occurrence of cells/masses randomly distributed, severe skeletal defects and delayed development. At 24 hpf a significant up-regulation of Pl-Hsp70, Pl-p38 Mapk, Pl-Univin and Pl-Cas8 genes was found, while at 48 hpf only for Pl-Univin was observed. Protein profile showed different patterns as a significant increase of Hsp70 and Hsp60 only after 48 hpf compared to controls. Conversely, P-p38 Mapk protein significantly increased at 24 hpf and decreased at 48 hpf. Our findings highlight that PS-NH 2 are able to disrupt sea urchin embryos development by modulating protein and gene profile providing new understandings into the signalling pathways involved.

Comparison of the in vitro and in vivo toxic effects of three sizes of zinc oxide (ZnO) particles using flounder gill (FG) cells and zebrafish embryos

NASA Astrophysics Data System (ADS)

Han, Li; Zhai, Yanan; Liu, Yang; Hao, Linhua; Guo, Huarong

2017-02-01

Nano-sized zinc oxide (nZnO) particles are one kind of the most commonly used metal oxide nanoparticles (NPs). This study compared the cytotoxic and embryotoxic effects of three increasing sized ZnO particles (ϕ 30 nm, 80-150 nm and 2 μm) in the flounder gill (FG) cells and zebrafish embryos, and analyzed the contribution of size, agglomeration and released Zn2+ to the toxic effects. All the tested ZnO particles were found to be highly toxic to both FG cells and zebrafish embryos. They induced growth inhibition, LDH release, morphological changes and apoptosis in FG cells in a concentration-, size- and time-dependent manner. Moreover, the release of LDH from the exposed FG cells into the medium occurred before the observable morphological changes happened. The ultrasonication treatment and addition of serum favored the dispersion of ZnO particles and alleviated the agglomeration, thus significantly increased the corresponding cytotoxicity. The released Zn2+ ions from ZnO particles into the extracellular medium only partially contributed to the cytotoxicity. All the three sizes of ZnO particles tested induced developmental malformations, decrease of hatching rates and lethality in zebrafish embryos, but size- and concentration- dependent toxic effects were not so obvious as in FG cells possibly due to the easy aggregation of ZnO particles in freshwater. In conclusion, both FG cells and zebrafish embryos are sensitive bioassay systems for safety assessment of ZnO particles and the environmental release of ZnO particles should be closely monitored as far as the safety of aquatic organisms is concerned.

Profitability and Market Value of Orphan Drug Companies: A Retrospective, Propensity-Matched Case-Control Study.

PubMed

Hughes, Dyfrig A; Poletti-Hughes, Jannine

2016-01-01

Concerns about the high cost of orphan drugs has led to questions being asked about the generosity of the incentives for development, and associated company profits. We conducted a retrospective, propensity score matched study of publicly-listed orphan companies. Cases were defined as holders of orphan drug market authorisation in Europe or the USA between 2000-12. Control companies were selected based on their propensity for being orphan drug market authorisation holders. We applied system General Method of Moments to test whether companies with orphan drug market authorization are valued higher, as measured by the Tobin's Q and market to book value ratios, and are more profitable based on return on assets, than non-orphan drug companies. 86 companies with orphan drug approvals in European (4), USA (61) or both (21) markets were matched with 258 controls. Following adjustment, orphan drug market authorization holders have a 9.6% (95% confidence interval, 0.6% to 18.7%) higher return on assets than non-orphan drug companies; Tobin's Q was higher by 9.9% (1.0% to 19.7%); market to book value by 15.7% (3.1% to 30.0%) and operating profit by 516% (CI 19.8% to 1011%). For each additional orphan drug sold, return on assets increased by 11.1% (0.6% to 21.3%), Tobin's Q by 2.7% (0.2% to 5.2%), and market to book value ratio by 5.8% (0.7% to 10.9%). Publicly listed pharmaceutical companies that are orphan drug market authorization holders are associated with higher market value and greater profits than companies not producing treatments for rare diseases.

Profitability and Market Value of Orphan Drug Companies: A Retrospective, Propensity-Matched Case-Control Study

PubMed Central

Hughes, Dyfrig A.; Poletti-Hughes, Jannine

2016-01-01

Background Concerns about the high cost of orphan drugs has led to questions being asked about the generosity of the incentives for development, and associated company profits. Methods We conducted a retrospective, propensity score matched study of publicly-listed orphan companies. Cases were defined as holders of orphan drug market authorisation in Europe or the USA between 2000–12. Control companies were selected based on their propensity for being orphan drug market authorisation holders. We applied system General Method of Moments to test whether companies with orphan drug market authorization are valued higher, as measured by the Tobin’s Q and market to book value ratios, and are more profitable based on return on assets, than non-orphan drug companies. Results 86 companies with orphan drug approvals in European (4), USA (61) or both (21) markets were matched with 258 controls. Following adjustment, orphan drug market authorization holders have a 9.6% (95% confidence interval, 0.6% to 18.7%) higher return on assets than non-orphan drug companies; Tobin’s Q was higher by 9.9% (1.0% to 19.7%); market to book value by 15.7% (3.1% to 30.0%) and operating profit by 516% (CI 19.8% to 1011%). For each additional orphan drug sold, return on assets increased by 11.1% (0.6% to 21.3%), Tobin’s Q by 2.7% (0.2% to 5.2%), and market to book value ratio by 5.8% (0.7% to 10.9%). Conclusions Publicly listed pharmaceutical companies that are orphan drug market authorization holders are associated with higher market value and greater profits than companies not producing treatments for rare diseases. PMID:27768685

"When the obvious brother is not there": political and cultural contexts of the orphan challenge in northern Uganda.

PubMed

Oleke, Christopher; Blystad, Astrid; Rekdal, Ole Bjørn

2005-12-01

It is estimated that two million of Uganda's children today are orphaned primarily due to AIDS. While recognising the immense impact of HIV/AIDS on the present orphan problem, this article calls for a broader historic and cultural contextualisation to reach an understanding of the vastness of the orphan challenge. The study on which the article is based was carried out among the Langi in Lira District, northern Uganda, with a prime focus on the situation of orphans within the extended family system. The data were collected through ethnographic fieldwork (8 months); in-depth interviews with community leaders (21), heads of households (45) and orphans (35); through focus group discussions (5) with adult men and women caring for orphans, community leaders and with orphans; and also through documentary review. A survey was conducted in 402 households. The findings reveal a transition over the past 30 years from a situation dominated by 'purposeful' voluntary exchange of non-orphaned children to one dominated by 'crisis fostering' of orphans. Sixty-three percent of the households caring for orphans were found to be no longer headed by resourceful paternal kin in a manner deemed culturally appropriate by the patrilineal Langi society, but rather by marginalised widows, grandmothers or other single women receiving little support from the paternal clan. This transition is partly linked to an abrupt discontinuation of the Langi 'widow inheritance' (laku) practice. It is argued that the consequential transformations in fostering practices in northern Uganda must be historically situated through a focus on the effects of armed conflicts and uprooting of the local pastoral and cotton-based economy, which have occurred since the late 1970s. These processes jointly produced dramatic economic marginalisation with highly disturbing consequences for orphans and their caretakers.

Treatment with sodium benzoate leads to malformation of zebrafish larvae.

PubMed

Tsay, Huey-Jen; Wang, Yun-Hsin; Chen, Wei-Li; Huang, Mei-Yun; Chen, Yau-Hung

2007-01-01

Sodium benzoate (SB) is a commonly used food preservative and anti-microbial agent in many foods from soup to cereals. However, little is known about the SB-induced toxicity and teratogenicity during early embryonic development. Here, we used zebrafish as a model to test the toxicity and teratogenicity because of their transparent eggs; therefore, the organogenesis of zebrafish embryos is easy to observe. After low dosages of SB (1-1000 ppm) treatment, the zebrafish embryos exhibited a 100% survival rate. As the exposure dosages increased, the survival rates decreased. No embryos survived after treatment with 2000 ppm SB. The 50% lethal dose (LD(50)) of zebrafish is found to be in the range of 1400-1500 ppm. Gut abnormalities, malformation of pronephros, defective hatching gland and edema in pericardial sac were observed after treatment with SB. Compared to untreated littermates (vehicle-treated control), SB-treated embryos exhibited significantly reduced tactile sensitivity frequencies of touch-induced movement (vehicle-treated control: 27.60+/-1.98 v.s. 1000 ppm SB: 7.89+/-5.28; N=30). Subtle changes are easily observed by staining with specific monoclonal antibodies F59, Znp1 and alpha6F to detect morphology changes in muscle fibers, motor axons and pronephros, respectively. Our data showed that the treatment of SB led to misalignment of muscle fibers, motor neuron innervations, excess acetyl-choline receptor cluster and defective pronephric tubes. On the basis of these observations, we suggest that sodium benzoate is able to induce neurotoxicity and nephrotoxicity of zebrafish larvae.

Maintenance of Xist Imprinting Depends on Chromatin Condensation State and Rnf12 Dosage in Mice.

PubMed

Fukuda, Atsushi; Mitani, Atsushi; Miyashita, Toshiyuki; Sado, Takashi; Umezawa, Akihiro; Akutsu, Hidenori

2016-10-01

In female mammals, activation of Xist (X-inactive specific transcript) is essential for establishment of X chromosome inactivation. During early embryonic development in mice, paternal Xist is preferentially expressed whereas maternal Xist (Xm-Xist) is silenced. Unlike autosomal imprinted genes, Xist imprinting for Xm-Xist silencing was erased in cloned or parthenogenetic but not fertilized embryos. However, the molecular mechanism underlying the variable nature of Xm-Xist imprinting is poorly understood. Here, we revealed that Xm-Xist silencing depends on chromatin condensation states at the Xist/Tsix genomic region and on Rnf12 expression levels. In early preimplantation, chromatin decondensation via H3K9me3 loss and histone acetylation gain caused Xm-Xist derepression irrespective of embryo type. Although the presence of the paternal genome during pronuclear formation impeded Xm-Xist derepression, Xm-Xist was robustly derepressed when the maternal genome was decondensed before fertilization. Once Xm-Xist was derepressed by chromatin alterations, the derepression was stably maintained and rescued XmXpΔ lethality, indicating that loss of Xm-Xist imprinting was irreversible. In late preimplantation, Oct4 served as a chromatin opener to create transcriptional permissive states at Xm-Xist/Tsix genomic loci. In parthenogenetic embryos, Rnf12 overdose caused Xm-Xist derepression via Xm-Tsix repression; physiological Rnf12 levels were essential for Xm-Xist silencing maintenance in fertilized embryos. Thus, chromatin condensation and fine-tuning of Rnf12 dosage were crucial for Xist imprint maintenance by silencing Xm-Xist.

Par-4, a Gene Required for Cytoplasmic Localization and Determination of Specific Cell Types in Caenorhabditis Elegans Embryogenesis

PubMed Central

Morton, D. G.; Roos, J. M.; Kemphues, K. J.

1992-01-01

Specification of some cell fates in the early Caenorhabditis elegans embryo is mediated by cytoplasmic localization under control of the maternal genome. Using nine newly isolated mutations, and two existing mutations, we have analyzed the role of the maternally expressed gene par-4 in cytoplasmic localization. We recovered seven new par-4 alleles in screens for maternal effect lethal mutations that result in failure to differentiate intestinal cells. Two additional par-4 mutations were identified in noncomplementation screens using strains with a high frequency of transposon mobility. All 11 mutations cause defects early in development of embryos produced by homozygous mutant mothers. Analysis with a deficiency in the region indicates that it33 is a strong loss-of-function mutation. par-4(it33) terminal stage embryos contain many cells, but show no morphogenesis, and are lacking intestinal cells. Temperature shifts with the it57ts allele suggest that the critical period for both intestinal differentiation and embryo viability begins during oogenesis, about 1.5 hr before fertilization, and ends before the four-cell stage. We propose that the primary function of the par-4 gene is to act as part of a maternally encoded system for cytoplasmic localization in the first cell cycle, with par-4 playing a particularly important role in the determination of intestine. Analysis of a par-4;par-2 double mutant suggests that par-4 and par-2 gene products interact in this system. PMID:1582558

Emotional development and nutritional status of HIV/AIDS orphaned children aged 6-12 years old in Thailand.

PubMed

Isaranurug, Sirikul; Chompikul, Jiraporn

2009-01-01

To explore the emotional development and nutritional status of HIV/AIDS orphans by their infection status. A community-based cross-sectional survey was conducted during January and December 2005 in four provinces and Bangkok Metropolis where the prevalence of HIV/AIDS among pregnant women was high. The study population consisted of 388 HIV/AIDS orphans who were maternal or paternal or double orphans aged 6-12 years old. The orphans' main caregivers gave informed consent to the project and assessed the emotional development of their orphaned children. The children were measured for weight, height, and emotional development by standard instruments. They were divided into three groups regarding their HIV/AIDS infection status reported by their caregivers: infected, non-infected, and unknown. The chi(2) test was used to determine the association between nutritional status and infection status. Regarding HIV/AIDS infected children, 19.1% were infected, 57.5% were not infected, and 23.4% were unknown. The main caregivers of all types of orphans were grandparents. Only 13.7% of infected orphans lived with their mothers. Most caregivers were females and more than 40 years old. Infected orphans had mean scores of overall emotional development and for each domain less than other groups. The mean scores of self-control and quick recovery were significantly different between infected and non-infected groups (P-value < 0.05). Nearly 50% of infected orphans were rather short and approximately 42% were under weight and light. The findings revealed a significant association between height for age, weight for age and infection status of orphans at a P-value of <0.001. Orphanhood itself is a vulnerable status and HIV/AIDS infected orphans are most vulnerable. Acceptable and friendly services for orphans and their families are crucial. The services should continue and protect stigmatization.

Household dynamics and socioeconomic conditions in the context of incident adolescent orphaning in KwaZulu-Natal, South Africa

PubMed Central

DeSilva, Mary Bachman; Skalicky, Anne; Beard, Jennifer; Cakwe, Mandisa; Zhuwau, Tom; Quinlan, Tim; Simon, Jonathon L.

2012-01-01

We compared demographics, socioeconomic status, and food insecurity between households with and without recent orphans in a region of high HIV/AIDS mortality in South Africa. We recruited a cohort of 197 recent orphans and 528 non-orphans ages 9–15 and their households using stratified cluster sampling. Households were classified into three groups: orphan-only (N=50); non-orphan-only (N=377); and mixed (N=210). Between September 2004 and May 2007, households were interviewed three times regarding demographics, income and assets, and food insecurity. Baseline bivariate associations were assessed using chi-square- and t-tests. Longitudinal bivariate associations and multivariate models were tested using generalized estimating equations. At baseline, mixed households generally exhibited greater characteristics of vulnerability than orphan and non-orphan households. They were larger, had older, less educated household heads, and reported a much smaller annual per capita income. Orphan households were more likely to report a death in the previous year, and less likely to have an adult employed. These differences persisted over the study. Even non-orphan households exhibited characteristics of vulnerability, with 14% reporting a death one year before baseline, 45% of whom were prime-age adults. At baseline, a much smaller proportion of orphan households reported receiving the child support grant than the other household types, but notably, there were no differences among households in receipt of the grant by Round 3. Household food insecurity was highly prevalent: more than one in five orphan-only and mixed households reported being food insecure in the previous month. These findings suggest that the effects of HIV/AIDS only exacerbate existing high levels of poverty in the district, as virtually all households are vulnerable regardless of orphan status. Community-level programs must help families address a spectrum of needs, including food security, caregiving, and financial support, as well as better target social welfare grants and make them more accessible to vulnerable households. PMID:24223622

Orphan Status, HIV Risk Behavior, and Mental Health Among Adolescents in Rural Kenya

PubMed Central

Drabkin, Anya S.; Stashko, Allison L.; Broverman, Sherryl A.; Ogwang-Odhiambo, Rose A.; Sikkema, Kathleen J.

2012-01-01

Objective To examine orphan status, mental health, social support, and HIV risk among adolescents in rural Kenya. Methods Randomly selected adolescents aged 10–18 years completed surveys assessing sexual activity, sex-related beliefs and self-efficacy, mental health, social support, caregiver–child communication, time since parental death, and economic resources. Analysis of covariance and regression analyses compared orphans and nonorphans; orphan status was tested as a moderator between well-being and HIV risk. Results Orphans reported poorer mental health, less social support, and fewer material resources. They did not differ from nonorphans on HIV risk indicators. Longer time since parental death was associated with poorer outcomes. In moderator analyses, emotional problems and poorer caregiver–youth communication were more strongly associated with lower sex-related self-efficacy for orphans. Conclusions Orphans are at higher risk for psychosocial problems. These problems may affect orphans’ self-efficacy for safer sex practices more than nonorphans. Decreased HIV risk could be one benefit of psychosocial interventions for orphans. PMID:22728899

The relationship between orphanhood and child fostering in sub-Saharan Africa, 1990s–2000s

PubMed Central

Grant, Monica J.; Yeatman, Sara

2012-01-01

In countries most afflicted by HIV/AIDS in sub-Saharan Africa, orphanhood has increased dramatically, but the potential consequences of the increase have been mitigated by the ability of households to absorb orphans. This paper examines what the rising levels of orphanhood mean for the common practice of non-orphan child fostering in regions of high and low HIV prevalence in sub-Saharan Africa, which has a long history of child fostering. Using Demographic and Health Survey data from 135 regions within 14 sub-Saharan countries that undertake HIV testing and have had at least two surveys, we examine changes in fostering patterns. In most regions, we find a more accommodating relationship between orphan and non-orphan fostering: communities are able to absorb the demand for both orphans and non-orphans. Where HIV prevalence exceeds ten per cent there is some evidence that the need to care for orphans is beginning to reduce opportunities for non-orphan fostering. PMID:22607126

From novice to expert: agroecological competences of children orphaned by AIDS compared to non-orphans in Benin.

PubMed

Fagbemissi, Rose C; Price, Lisa L

2011-01-10

AIDS has created new vulnerabilities for rural African households due to prime-age adult mortality and is assumed to lead to impairment of the intergenerational transfer of farming knowledge. There has been scant research to date, however, on the impacts of parental death on farming knowledge of children made orphans by AIDS. The question we investigate is if there is a difference in agricultural expertise between AIDS affected and non-affected adults and children. The research was carried out in rural Benin with 77 informants randomly selected according to their AIDS status: 13 affected and 13 non-affected adults; 13 paternal, 13 maternal and 13 double orphans; and 12 non-orphan children. Informants descriptions from pile sorting exercises of maize and cowpea pests were categorized and then aggregated into descriptions based form (morphology) and function (utility) and used to determine whether the moving from novice to expert is impaired by children orphaned by AIDS. Differences and similarities in responses were determined using the Fischer exact test and the Cochran-Mantzel-Haenszel test. No significant differences were found between AIDS affected and non-affected adults. Results of the study do reveal differences in the use of form and function descriptors among the children. There is a statistically significant difference in the use of form descriptors between one-parent orphans and non-orphans and in descriptors of specific damages to maize. One-parent paternal orphans were exactly like non-affected adults in their 50/50 balanced expertise in the use of both form and function descriptors. One-parent orphans also had the highest number of descriptors used by children overall and these descriptors are spread across the various aspects of the knowledge domain relative to non-orphans. Rather than a knowledge loss for one-parent orphans, particularly paternal orphans, we believe we are witnessing acceleration into adult knowledge frames. This expertise of one-parent orphans may be a result of a combination of factors deserving further investigation including enhanced hands-on work experience with the food crops in the field and the expertise available from the surviving parent coupled with the value of the food resource to the household.

Expression of inactive glutathione peroxidase 4 leads to embryonic lethality, and inactivation of the Alox15 gene does not rescue such knock-in mice.

PubMed

Brütsch, Simone Hanna; Wang, Chi Chiu; Li, Lu; Stender, Hannelore; Neziroglu, Nilgün; Richter, Constanze; Kuhn, Hartmut; Borchert, Astrid

2015-02-01

Glutathione peroxidases (Gpx) and lipoxygenases (Alox) are functional counterplayers in the metabolism of hydroperoxy lipids that regulate cellular redox homeostasis. Gpx4 is a moonlighting protein that has been implicated not only as an enzyme in anti-oxidative defense, gene expression regulation, and programmed cell death, but also as a structural protein in spermatogenesis. Homozygous Gpx4 knock-out mice are not viable, but molecular reasons for intrauterine lethality are not completely understood. This study was aimed at investigating whether the lack of catalytic activity or the impaired function as structural protein is the dominant reason for embryonic lethality. We further explored whether the pro-oxidative enzyme mouse 12/15 lipoxygenase (Alox15) plays a major role in embryonic lethality of Gpx4-deficient mice. To achieve these goals, we first created knock-in mice, which express a catalytically inactive Gpx4 mutant (Sec46Ala). As homozygous Gpx4-knock-out mice Sec46Ala-Gpx4(+/+) knock-in animals are not viable but undergo intrauterine resorption between embryonic day 6 and 7 (E6-7). In contrast, heterozygous knock-in mice (Sec46Ala-Gpx4(-/+)) are viable, fertile and do not show major phenotypic alterations. Interestingly, homozygous Alox15 deficiency did not rescue the U46A-Gpx4(+/+) mice from embryonic lethality. In fact, when heterozygous U46A-Gpx4(-/+) mice were stepwise crossed into an Alox15-deficent background, no viable U46A-Gpx4(+/+)+Alox15(-/-) individuals were obtained. However, we were able to identify U46A-Gpx4(+/+)+Alox15(-/-) embryos in the state of resorption around E7. These data suggest that the lack of catalytic activity is the major reason for the embryonic lethality of Gpx4(-/-) mice and that systemic inactivation of the Alox15 gene does not rescue homozygous knock-in mice expressing catalytically silent Gpx4.

Evidence for Functional Differentiation among Drosophila Septins in Cytokinesis and Cellularization

PubMed Central

Adam, Jennifer C.; Pringle, John R.; Peifer, Mark

2000-01-01

The septins are a conserved family of proteins that are involved in cytokinesis and other aspects of cell-surface organization. In Drosophila melanogaster, null mutations in the pnut septin gene are recessive lethal, but homozygous pnut mutants complete embryogenesis and survive until the pupal stage. Because the completion of cellularization and other aspects of early development seemed likely to be due to maternally contributed Pnut product, we attempted to generate embryos lacking the maternal contribution in order to explore the roles of Pnut in these processes. We used two methods, the production of germline clones homozygous for a pnut mutation and the rescue of pnut homozygous mutant flies by a pnut+ transgene under control of the hsp70 promoter. Remarkably, the pnut germline-clone females produced eggs, indicating that stem-cell and cystoblast divisions in the female germline do not require Pnut. Moreover, the Pnut-deficient embryos obtained by either method completed early syncytial development and began cellularization of the embryo normally. However, during the later stages of cellularization, the organization of the actin cytoskeleton at the leading edge of the invaginating furrows became progressively more abnormal, and the embryos displayed widespread defects in cell and embryo morphology beginning at gastrulation. Examination of two other septins showed that Sep1 was not detectable at the cellularization front in the Pnut-deficient embryos, whereas Sep2 was still present in normal levels. Thus, it is possible that Sep2 (perhaps in conjunction with other septins such as Sep4 and Sep5) fulfills an essential septin role during the organization and initial ingression of the cellularization furrow even in the absence of Pnut and Sep1. Together, the results suggest that some cell-division events in Drosophila do not require septin function, that there is functional differentiation among the Drosophila septins, or both. PMID:10982405

Toxicity of weathered Deepwater Horizon oil to bay anchovy (Anchoa mitchilli) embryos.

PubMed

O'Shaughnessy, Kathryn A; Forth, Heather; Takeshita, Ryan; Chesney, Edward J

2018-02-01

The BP-contracted Deepwater Horizon Macondo well blowout occurred on 20 April 2010 and lasted nearly three months. The well released millions of barrels of crude oil into the northern Gulf of Mexico, causing extensive impacts on pelagic, benthic, and estuarine fish species. The bay anchovy (Anchoa mitchilli) is an important zooplanktivore in the Gulf, serving as an ecological link between lower trophic levels and pelagic predatory fish species. Bay anchovy spawn from May through November in shallow inshore and estuarine waters throughout the Gulf. Because their buoyant embryos are a dominant part of the inshore ichthyoplankton throughout the summer, it is likely bay anchovy embryos encountered oil in coastal estuaries during the summer and fall of 2010. Bay anchovy embryos were exposed to a range of concentrations of two field-collected Deepwater Horizon oils as high-energy and low-energy water accommodated fractions (HEWAFs and LEWAFs, respectively) for 48h. The median lethal concentrations (LC 50 ) were lower in exposures with the more weathered oil (HEWAF, 1.48µg/L TPAH50; LEWAF, 1.58µg/L TPAH50) compared to the less weathered oil (HEWAF, 3.87µg/L TPAH50; LEWAF, 4.28µg/L TPAH50). To measure delayed mortality and life stage sensitivity between embryos and larvae, an additional 24h acute HEWAF exposure using the more weathered oil was run followed by a 24h grow-out period. Here the LC 50 was 9.71µg/L TPAH50 after the grow-out phase, suggesting a toxic effect of oil at the embryonic or hatching stage. We also found that exposures prepared with the more weathered Slick B oil produced lower LC 50 values compared to the exposures prepared with Slick A oil. Our results demonstrate that even relatively acute environmental exposure times can have a detrimental effect on bay anchovy embryos. Copyright © 2017 Elsevier Inc. All rights reserved.

Psychological distress amongst AIDS-orphaned children in urban South Africa.

PubMed

Cluver, Lucie; Gardner, Frances; Operario, Don

2007-08-01

South Africa is predicted to have 2.3 million children orphaned by Acquired Immune Deficiency Syndrome (AIDS) by 2020 (Actuarial Society of South Africa, 2005). There is little knowledge about impacts of AIDS-related bereavement on children, to aid planning of services. This study aimed to investigate psychological consequences of AIDS orphanhood in urban township areas of Cape Town, South Africa, compared to control groups of children and adolescents orphaned by other causes, and non-orphans. One thousand and twenty-five children and adolescents (aged 10-19) were interviewed using socio-demographic questionnaires and standardised scales for assessing depression, anxiety, post-traumatic stress, peer problems, delinquency and conduct problems. Controlling for socio-demographic factors such as age, gender, formal/informal dwelling and age at orphanhood, children orphaned by AIDS were more likely to report symptoms of depression, peer relationship problems, post-traumatic stress, delinquency and conduct problems than both children orphaned by other causes and non-orphaned children. Anxiety showed no differences. AIDS-orphaned children were more likely to report suicidal ideation. Compared to Western norms, AIDS-orphaned children showed higher levels of internalising problems and delinquency, but lower levels of conduct problems. Children orphaned by AIDS may be a particularly vulnerable group in terms of emotional and, to a lesser extent, behavioural problems. Intervention programs are necessary to ameliorate the psychological sequelae of losing a parent to AIDS.

[Orphan diseases and orphan medicines: a Belgian and European study].

PubMed

Denis, Alain; Mergaert, Lut; Fostier, Christel; Cleemput, Irina; Simoens, Steven

2009-12-01

The objective of this study is to analyze policies concerning orphan medicines, used to treat patients suffering from a rare disease. The decisions about orphan designation and marketing authorization of orphan medicines are taken at European level, but each Member State is responsible for decisions regarding reimbursement. The European measures to encourage the development of orphan medicines, such as market exclusivity for a period of ten years, seem to be successful. However, this market exclusivity should be revised once the profitability of such medicines has clearly been demonstrated. Our study recommends the implementation of patient registries at the European level in order to describe the natural evolution of rare diseases and the efficacy of orphan medicines, the majority of which are relatively expensive. In 2008, Belgian social security services reimbursed orphan medicines for an amount of 66 million euro, accounting for more than 5% of the hospital pharmaceutical budget. The reimbursement of an orphan medicine to an individual patient is subject to multiple conditions. Our study recommends that a unique counter within the NIHDI is created which centralizes all reimbursement requests. The reimbursement of an orphan medicine must be linked to the provision of standardized information needed for a patient register. The NIHDI administration could then, in collaboration with external experts, evaluate reimbursement requests and ensure a coherent application of reimbursement criteria.

Role of traditional healers in psychosocial support in caring for the orphans: a case of Dar-es Salaam City, Tanzania.

PubMed

Kayombo, Edmund J; Mbwambo, Zakaria H; Massila, Mariam

2005-07-29

Orphans are an increasing problem in developing countries particularly in Africa; due to the HIV/AIDS pandemic; and needs collective effort in intervention processes by including all stakeholders right from the grass roots level. This paper attempts to present the role of traditional healers in psychosocial support for orphan children in Dar-es-Salaam City with special focus on those whose parents have died because of HIV/AIDS. Six traditional healers who were involved in taking care of orphans were visited at their "vilinge" (traditional clinics). In total they had 72 orphans, 31 being boys and 41 being girls with age range from 3 years to 19. It was learned that traditional healers, besides providing remedies for illnesses/diseases of orphans, they also provided other basic needs. Further, they even provided psychosocial support allowing children to cope with orphan hood life with ease. Traditional healers are living within communities at the grass roots level; and appear unnoticed hidden forces, which are involved in taking care of orphans. This role of traditional healers in taking care of orphans needs to be recognised and even scaling it up by empowering them both in financial terms and training in basic skills of psychosocial techniques in how to handle orphans, in order to reduce discrimination and stigmatisation in the communities where they live.

Inverse association of natural mentoring relationship with distress mental health in children orphaned by AIDS.

PubMed

Onuoha, Francis N; Munakata, Tsunetsugu

2010-01-16

The magnitude of the AIDS-orphaned children crisis in sub-Saharan Africa has so overstretched the resource of most families that the collapse of fostering in the sub-region seems imminent (UNICEF, 2003), fueling the need for a complementary/alternative care. This paper examines the probability of the natural mentoring care to ameliorate distress mental health in children orphaned by AIDS. 952 children, mean age about 14 years, from local community schools and child-care centers in Kampala (Uganda) and Mafikeng/Klerksdorp (South Africa) towns participated in the study. The design has AIDS-orphaned group (n = 373) and two control groups: Other-causes orphaned (n = 287) and non-orphaned (n = 290) children. We use measures of child abuse, depression, social discrimination, anxiety, parental/foster care, self-esteem, and social support to estimate mental health. Natural mentoring care is measured with the Ragins and McFarlin (1990) Mentor Role Instrument as adapted. AIDS-orphaned children having a natural mentor showed significant decreased distress mental health factors. Similar evidence was not observed in the control groups. Also being in a natural mentoring relationship inversely related to distress mental health factors in the AIDS-orphaned group, in particular. AIDS-orphaned children who scored high mentoring relationship showed significant lowest distress mental health factors that did those who scored moderate and low mentoring relationship. Natural mentoring care seems more beneficial to ameliorate distress mental health in AIDS-orphaned children (many of whom are double-orphans, having no biological parents) than in children in the control groups.

Inverse association of natural mentoring relationship with distress mental health in children orphaned by AIDS

PubMed Central

2010-01-01

Background The magnitude of the AIDS-orphaned children crisis in sub-Saharan Africa has so overstretched the resource of most families that the collapse of fostering in the sub-region seems imminent (UNICEF, 2003), fueling the need for a complementary/alternative care. This paper examines the probability of the natural mentoring care to ameliorate distress mental health in children orphaned by AIDS. Methods 952 children, mean age about 14 years, from local community schools and child-care centers in Kampala (Uganda) and Mafikeng/Klerksdorp (South Africa) towns participated in the study. The design has AIDS-orphaned group (n = 373) and two control groups: Other-causes orphaned (n = 287) and non-orphaned (n = 290) children. We use measures of child abuse, depression, social discrimination, anxiety, parental/foster care, self-esteem, and social support to estimate mental health. Natural mentoring care is measured with the Ragins and McFarlin (1990) Mentor Role Instrument as adapted. Results AIDS-orphaned children having a natural mentor showed significant decreased distress mental health factors. Similar evidence was not observed in the control groups. Also being in a natural mentoring relationship inversely related to distress mental health factors in the AIDS-orphaned group, in particular. AIDS-orphaned children who scored high mentoring relationship showed significant lowest distress mental health factors that did those who scored moderate and low mentoring relationship. Conclusions Natural mentoring care seems more beneficial to ameliorate distress mental health in AIDS-orphaned children (many of whom are double-orphans, having no biological parents) than in children in the control groups. PMID:20078888

Children’s psychosocial wellbeing in the context of HIV/AIDS and poverty: a comparative investigation of orphaned and non-orphaned children living in South Africa

PubMed Central

2014-01-01

Background Recent studies have questioned whether orphanhood is primarily associated with key dimensions of psycho-social wellbeing in children living in circumstances of material deprivation and high prevalence of HIV and AIDS. Methods This study uses cross-sectional data from a longitudinal study conducted between 2004-2007 to examine the psychosocial well-being of orphans and non-orphans in the Amajuba District of KwaZulu-Natal, South Africa. Psychosocial wellbeing included an assessment of orphans’ and non orphans’ level of anxiety and depression, affability and resilience. Stratified cluster sampling, based on both school and age, was used to construct a cohort of recent orphans and non-orphans and their households, randomly selected from schools. Results Levels of anxiety and depression, affability and resilience did not differ significantly between orphans and non-orphans, nor did salient household, poverty and caregiver characteristics vary substantially amongst orphans and non-orphans. Multivariate analyses indicated that children’s psychosocial outcomes, when controlling for orphan status and related demographic variables were more strongly influenced by household composition/size, living above or below the poverty threshold and factors associated with the caregiver-child relationship and caregiver health. Conclusions The results muster additional evidence for moving beyond narrow definitions of vulnerability associated exclusively with orphanhood to consider the multitude of material, social and relational factors affecting the psycho-social well-being of children in general who are living in circumstances of poverty and HIV and AIDS. PMID:24938864

Predictors of Mental Health Resilience in Children who Have Been Parentally Bereaved by AIDS in Urban South Africa.

PubMed

Collishaw, Stephan; Gardner, Frances; Lawrence Aber, J; Cluver, Lucie

2016-05-01

Children parentally bereaved by AIDS experience high rates of mental health problems. However, there is considerable variability in outcomes, and some show no mental health problems even when followed over time. Primary aims were to identify predictors of resilient adaptation at child, family and community levels within a group of AIDS-orphaned children, and to consider their cumulative influence. A secondary aim was to test whether predictors were of particular influence among children orphaned by AIDS relative to non-orphaned and other-orphaned children. AIDS-orphaned (n = 290), other-orphaned (n = 163) and non-orphaned (n = 202) adolescents living in informal settlements in Cape Town, South Africa were assessed on two occasions 4 years apart (mean age 13.5 years at Time 1, range = 10-19 years). Self-report mental health screens were used to operationalise resilience in AIDS-orphaned children as the absence of clinical-range symptoms of PTSD, anxiety, depression, conduct problems, and suicidality. A quarter of AIDS-orphaned children (24 %) showed no evidence of mental health problems at either wave. Child physical health, better caregiving quality, food security, better peer relationship quality, and lower exposure to community violence, bullying or stigma at baseline predicted sustained resilience. There were cumulative influences across predictors. Associations with mental health showed little variation by child age or gender, or between orphaned and non-orphaned children. Mental health resilience is associated with multiple processes across child, family and community levels of influence. Caution is needed in making causal inferences.

A targeted deletion/insertion in the mouse Pcsk1 locus is associated with homozygous embryo preimplantation lethality, mutant allele preferential transmission and heterozygous female susceptibility to dietary fat.

PubMed

Mbikay, Majambu; Croissandeau, Gilles; Sirois, Francine; Anini, Younes; Mayne, Janice; Seidah, Nabil G; Chrétien, Michel

2007-06-15

Proprotein convertase 1 (PC1) is a neuroendocrine proteinase involved in the proteolytic activation of precursors to hormones and neuropeptides. To determine the physiological importance of PC1, we produced a mutant mouse from embryonic stem cells in which its locus (Pcsk1) had been inactivated by homologous recombination. The inactivating mutation consisted of a 32.7-kb internal deletion and a 1.8 kb insertion of the bacterial neomycin resistance gene (neo) under the mouse phosphoglycerate kinase 1 protein (PGKneo). Intercross of Pcsk1(+/-) mice produced no Pcsk1(-/-) offspring or blastocysts; in addition, more than 80% of the offspring were Pcsk1(+/-). These observations suggested that the mutation caused preimplantation lethality of homozygous embryos and preferential transmission of the mutant allele. Interestingly, RT-PCR analysis on RNA from endocrine tissues from Pcsk1(+/-) mice revealed the presence of aberrant transcripts specifying the N-terminal half of the PC1 propeptide fused to neo gene product. Mass spectrometric profiles of proopiomelanocortin-derived peptides in the anterior pituitary were similar between Pcsk1(+/-) and Pcsk1(+/+) mice, but significantly different between male and female mice of the same genotype. Relative to their wild-type counterparts, female mutant mice exhibited stunted growth under a low fat diet, and catch-up growth under a high-fat diet. The complex phenotype exhibited by this Pcsk1 mutant mouse model may be due to PC1 deficiency aggravated by expression of aberrant gene products from the mutant allele.

Multiple transcription factors directly regulate Hox gene lin-39 expression in ventral hypodermal cells of the C. elegans embryo and larva, including the hypodermal fate regulators LIN-26 and ELT-6.

PubMed

Liu, Wan-Ju; Reece-Hoyes, John S; Walhout, Albertha J M; Eisenmann, David M

2014-05-13

Hox genes encode master regulators of regional fate specification during early metazoan development. Much is known about the initiation and regulation of Hox gene expression in Drosophila and vertebrates, but less is known in the non-arthropod invertebrate model system, C. elegans. The C. elegans Hox gene lin-39 is required for correct fate specification in the midbody region, including the Vulval Precursor Cells (VPCs). To better understand lin-39 regulation and function, we aimed to identify transcription factors necessary for lin-39 expression in the VPCs, and in particular sought factors that initiate lin-39 expression in the embryo. We used the yeast one-hybrid (Y1H) method to screen for factors that bound to 13 fragments from the lin-39 region: twelve fragments contained sequences conserved between C. elegans and two other nematode species, while one fragment was known to drive reporter gene expression in the early embryo in cells that generate the VPCs. Sixteen transcription factors that bind to eight lin-39 genomic fragments were identified in yeast, and we characterized several factors by verifying their physical interactions in vitro, and showing that reduction of their function leads to alterations in lin-39 levels and lin-39::GFP reporter expression in vivo. Three factors, the orphan nuclear hormone receptor NHR-43, the hypodermal fate regulator LIN-26, and the GATA factor ELT-6 positively regulate lin-39 expression in the embryonic precursors to the VPCs. In particular, ELT-6 interacts with an enhancer that drives GFP expression in the early embryo, and the ELT-6 site we identified is necessary for proper embryonic expression. These three factors, along with the factors ZTF-17, BED-3 and TBX-9, also positively regulate lin-39 expression in the larval VPCs. These results significantly expand the number of factors known to directly bind and regulate lin-39 expression, identify the first factors required for lin-39 expression in the embryo, and hint at a positive feedback mechanism involving GATA factors that maintains lin-39 expression in the vulval lineage. This work indicates that, as in other organisms, the regulation of Hox gene expression in C. elegans is complicated, redundant and robust.

Radiation sensitivity of the gastrula-stage embryo: Chromosome aberrations and mutation induction in lacZ transgenic mice: The roles of DNA double-strand break repair systems.

PubMed

Jacquet, Paul; van Buul, Paul; van Duijn-Goedhart, Annemarie; Reynaud, Karine; Buset, Jasmine; Neefs, Mieke; Michaux, Arlette; Monsieurs, Pieter; de Boer, Peter; Baatout, Sarah

2015-10-01

At the gastrula phase of development, just after the onset of implantation, the embryo proper is characterized by extremely rapid cell proliferation. The importance of DNA repair is illustrated by embryonic lethality at this stage after ablation of the genes involved. Insight into mutation induction is called for by the fact that women often do not realize they are pregnant, shortly after implantation, a circumstance which may have important consequences when women are subjected to medical imaging using ionizing radiation. We screened gastrula embryos for DNA synthesis, nuclear morphology, growth, and chromosome aberrations (CA) shortly after irradiation with doses up to 2.5Gy. In order to obtain an insight into the importance of DNA repair for CA induction, we included mutants for the non-homologous end joining (NHEJ) and homologous recombination repair (HRR) pathways, as well as Parp1-/- and p53+/- embryos. With the pUR288 shuttle vector assay, we determined the radiation sensitivity for point mutations and small deletions detected in young adults. We found increased numbers of abnormal nuclei 5h after irradiation; an indication of disturbed development was also observed around this time. Chromosome aberrations 7h after irradiation arose in all genotypes and were mainly of the chromatid type, in agreement with a cell cycle dominated by S-phase. Increased frequencies of CA were found for NHEJ and HR mutants. Gastrula embryos are unusual in that they are low in exchange induction, even after compromised HR. Gastrula embryos were radiation sensitive in the pUR288 shuttle vector assay, giving the highest mutation induction ever reported for this genetic toxicology model. On theoretical grounds, a delayed radiation response must be involved. The compromised developmental profile after doses up to 2.5Gy likely is caused by both apoptosis and later cell death due to large deletions. Our data indicate a distinct radiation-sensitive profile of gastrula embryos, including some stage-specific aspects that are not as yet understood. Copyright © 2015 Elsevier B.V. All rights reserved.

[GPCRs heterodimerization: a new way towards the discovery of function for the orphan receptors?].

PubMed

Levoye, Angélique; Jockers, Ralf

2007-01-01

G protein-coupled receptors (GPCRs), also called seven transmembrane domain (7TM) proteins, represent the largest family of cell surface receptors. GPCRs control a variety of physiological processes, are involved in multiple diseases and are major drug targets. Despite a vast effort of academic and industrial research, more than one hundred receptors remain orphans. These orphan GPCRs offer a great potential for drug discovery, as almost 60% of currently prescribed drugs target GPCRs. Deorphenization strategies have concentrated mainly on the identification of the natural ligands of these proteins. Recent advances have shown that orphan GPCRs, similar to orphan nuclear receptors, can regulate the function of non-orphan receptors by heterodimerization. These findings not only help to better understand the extraordinary diversity of GPCRs, but also open new perspectives for the identification of the function of these orphan receptors that hold great therapeutic potential.

Developmental toxicity of treated municipal wastewater effluent on Bombina orientalis (Amphibia: Anura) embryos.

PubMed

Park, Chan Jin; Ahn, Hyo Min; Cho, Seong Chan; Kim, Tae-Hoon; Oh, Jong-Min; Ahn, Hong Kyu; Chun, Seung-Hoon; Gye, Myung Chan

2014-04-01

Amphibian populations have been decreasing in urban freshwater systems in Korea. To elucidate the biological safety of treated wastewater effluent (TWE) in the Tancheon basin, the capital area of Korea, a 7-d-exposure Bombina orientalis embryo developmental toxicity assay was examined during the breeding season. In March, there were no significant differences in embryonic survival or malformation among the water samples. In July, following monsoon precipitation, embryonic lethality in TWE was significantly higher than in the upstream water sample. Malformation in TWE and TWE-mixed waters was significantly higher than in the control and upstream water samples. Tail muscle height of tadpoles also significantly decreased in TWE and TWE-mixed waters. Heavy metals were not detected in any samples. Total nitrogen, total phosphorous, and chemical oxygen demand in TWE markedly increased together with a decrease in dissolved oxygen in July. The increase in organic and inorganic loading following precipitation could have made TWE and TWE-mixed water not suitable for embryonic development. Though being managed based on physicochemical criteria, the water quality of TWE may not be sufficient to assure normal development of amphibian embryos. An amphibian developmental toxicity assay would be helpful for the water-quality management of TWE and urban freshwater systems in Korea. © 2014 SETAC.

Triazole-induced toxicity in developing rare minnow (Gobiocypris rarus) embryos.

PubMed

Zhu, Bin; Liu, Lei; Gong, Yu-Xin; Ling, Fei; Wang, Gao-Xue

2014-12-01

Using rare minnow (Gobiocypris rarus) at early-life stages as experimental models, the developmental toxicity of five widely used triazole fungicides (myclobutanil, fluconazole, flusilazole, triflumizole, and epoxiconazole) were investigated following exposure to 1-15 mg/L for 72 h. Meanwhile, morphological parameters (body length, body weight, and heart rate), enzyme activities (superoxide dismutase (SOD), glutathione S-transferase (GST), adenosine triphosphatase (ATPase), and acetyl cholinesterase (AChE)), and mRNA levels (hsp70, mstn, mt, apaf1, vezf1, and cyp1a) were also recorded following exposure to 0.2, 1.0, and 5.0 mg/L for 72 h. Results indicated that increased malformation and mortality, decreased body length, body weight, and heart rate provide a concentration-dependent pattern; values of 72 h LC50 (median lethal concentration) and EC50 (median effective concentration) ranged from 3 to 12 mg/L. Most importantly, the results of the present study suggest that even at the lowest concentration, 0.2 mg/L, five triazole fungicides also caused notable changes in enzyme activities and mRNA levels. Overall, the present study points out that those five triazole fungicides are highly toxic to the early development of G. rarus embryos. The information presented in this study will be helpful in better understanding the toxicity induced by triazole fungicides in fish embryos.

Comparative ecotoxicity of potential biofuels to water flea (Daphnia magna), zebrafish (Danio rerio) and Chinese hamster (Cricetulus griseus) V79 cells.

PubMed

Heger, Sebastian; Du, Miaomiao; Bauer, Kevin; Schäffer, Andreas; Hollert, Henner

2018-08-01

The ecotoxicity of two biofuel candidates (1‑octanol and 2‑butanone) was investigated by an integrative test strategy using three bioassays: the acute immobilisation test with water flea (D. magna), the fish embryo acute toxicity test with zebrafish (Danio rerio) and the in vitro micronucleus assay with Chinese hamster (Cricetulus griseus) V79 cells. The median effective concentration (EC 50 ) values were 14.9±0.66mgL -1 for 1‑octanol, and 2152.1±44.6mgL -1 for 2‑butanone in the D. magna test. Both 1‑octanol and 2‑butanone caused teratogenic and lethal effects on zebrafish embryos, while exposure to 1‑octanol significantly induced these effects at concentrations ≥2.0mgL -1 . These results indicate that 1‑octanol exert much higher ecotoxicity than 2‑butanone to D. magna and zebrafish embryos. Moreover, both 1‑octanol and 2‑butanone did not cause significant genotoxic effects, while their metabolites significantly induced micronuclei in V79 cells. The present study proposed an integrative test approach to evaluate the potential ecotoxicity of biofuels using simple, quick and inexpensive bioassays. Copyright © 2018 Elsevier B.V. All rights reserved.

Targeted gene expression without a tissue-specific promoter: creating mosaic embryos using laser-induced single-cell heat shock

NASA Technical Reports Server (NTRS)

Halfon, M. S.; Kose, H.; Chiba, A.; Keshishian, H.

1997-01-01

We have developed a method to target gene expression in the Drosophila embryo to a specific cell without having a promoter that directs expression in that particular cell. Using a digitally enhanced imaging system to identify single cells within the living embryo, we apply a heat shock to each cell individually by using a laser microbeam. A 1- to 2-min laser treatment is sufficient to induce a heat-shock response but is not lethal to the heat-shocked cells. Induction of heat shock was measured in a variety of cell types, including neurons and somatic muscles, by the expression of beta-galactosidase from an hsp26-lacZ reporter construct or by expression of a UAS target gene after induction of hsGAL4. We discuss the applicability of this technique to ectopic gene expression studies, lineage tracing, gene inactivation studies, and studies of cells in vitro. Laser heat shock is a versatile technique that can be adapted for use in a variety of research organisms and is useful for any studies in which it is desirable to express a given gene in only a distinct cell or clone of cells, either transiently or constitutively, at a time point of choice.

InP/ZnS QDs exposure induces developmental toxicity in rare minnow (Gobiocypris rarus) embryos.

PubMed

Chen, Yao; Yang, Yang; Ou, Fang; Liu, Li; Liu, Xiao-Hong; Wang, Zhi-Jian; Jin, Li

2018-04-05

We investigated the in vivo toxicity of InP/ZnS quantum dots (QDs) in Chinese rare minnow (Gobiocypris rarus) embryos. The 72 h post-fertilization (hpf) LC 50 (median lethal concentration) was 1678.007 nmol/L. Rare minnows exposed to InP/ZnS QDs exhibited decreased spontaneous movement, decreased survival and hatchability rates, and an increased malformation rate. Pericardial edema, spinal curvature, bent tails and vitelline cysts were observed. Embryonic Wnt8a and Mstn mRNA levels were significantly up-regulated after InP/ZnS QDs treatment at 48 hpf (200 nmol/L) (p < 0.05). The superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels at 96 hpf (800 nmol/L) had an increasing trend. Hsp70 mRNA expression was significantly changed at 48 hpf (200 nmol/L), but compared with the blank control, the different InP/ZnS QDs treatments did not significantly change the Olive tail moments (p > 0.05). Thus, InP/ZnS QDs caused teratogenic effects and death during the development of Chinese rare minnow embryos, but InP/ZnS QDs did not cause significant genetic toxicity during Chinese rare minnow development. Copyright © 2018 Elsevier B.V. All rights reserved.

Chick embryo chorioallantoic membrane (CAM): an alternative predictive model in acute toxicological studies for anti-cancer drugs.

PubMed

Kue, Chin Siang; Tan, Kae Yi; Lam, May Lynn; Lee, Hong Boon

2015-01-01

The chick embryo chorioallantoic membrane (CAM) is a preclinical model widely used for vascular and anti-vascular effects of therapeutic agents in vivo. In this study, we examine the suitability of CAM as a predictive model for acute toxicology studies of drugs by comparing it to conventional mouse and rat models for 10 FDA-approved anticancer drugs (paclitaxel, carmustine, camptothecin, cyclophosphamide, vincristine, cisplatin, aloin, mitomycin C, actinomycin-D, melphalan). Suitable formulations for intravenous administration were determined before the average of median lethal dose (LD50) and median survival dose (SD(50)) in the CAM were measured and calculated for these drugs. The resultant ideal LD(50) values were correlated to those reported in the literature using Pearson's correlation test for both intravenous and intraperitoneal routes of injection in rodents. Our results showed moderate correlations (r(2)=0.42 - 0.68, P<0.005-0.05) between the ideal LD(50) values obtained using the CAM model with LD(50) values from mice and rats models for both intravenous and intraperitoneal administrations, suggesting that the chick embryo may be a suitable alternative model for acute drug toxicity screening before embarking on full toxicological investigations in rodents in development of anticancer drugs.

Embryonic demise caused by targeted disruption of a cysteine protease Dub-2.

PubMed

Baek, Kwang-Hyun; Lee, Heyjin; Yang, Sunmee; Lim, Soo-Bin; Lee, Wonwoo; Lee, Jeoung Eun; Lim, Jung-Jin; Jun, Kisun; Lee, Dong-Ryul; Chung, Young

2012-01-01

A plethora of biological metabolisms are regulated by the mechanisms of ubiquitination, wherein this process is balanced with the action of deubiquitination system. Dub-2 is an IL-2-inducible, immediate-early gene that encodes a deubiquitinating enzyme with growth regulatory activity. DUB-2 presumably removes ubiquitin from ubiquitin-conjugated target proteins regulating ubiquitin-mediated proteolysis, but its specific target proteins are unknown yet. To elucidate the functional role of Dub-2, we generated genetically modified mice by introducing neo cassette into the second exon of Dub-2 and then homologous recombination was done to completely abrogate the activity of DUB-2 proteins. We generated Dub-2+/- heterozygous mice showing a normal phenotype and are fertile, whereas new born mouse of Dub-2-/- homozygous alleles could not survive. In addition, Dub-2-/- embryo could not be seen between E6.5 and E12.5 stages. Furthermore, the number of embryos showing normal embryonic development for further stages is decreased in heterozygotes. Even embryonic stem cells from inner cell mass of Dub-2-/- embryos could not be established. Our study suggests that the targeted disruption of Dub-2 may cause embryonic lethality during early gestation, possibly due to the failure of cell proliferation during hatching process.

Chick embryo chorioallantoic membrane (CAM): an alternative predictive model in acute toxicological studies for anti-cancer drugs

PubMed Central

KUE, Chin Siang; TAN, Kae Yi; LAM, May Lynn; LEE, Hong Boon

2015-01-01

The chick embryo chorioallantoic membrane (CAM) is a preclinical model widely used for vascular and anti-vascular effects of therapeutic agents in vivo. In this study, we examine the suitability of CAM as a predictive model for acute toxicology studies of drugs by comparing it to conventional mouse and rat models for 10 FDA-approved anticancer drugs (paclitaxel, carmustine, camptothecin, cyclophosphamide, vincristine, cisplatin, aloin, mitomycin C, actinomycin-D, melphalan). Suitable formulations for intravenous administration were determined before the average of median lethal dose (LD50) and median survival dose (SD50) in the CAM were measured and calculated for these drugs. The resultant ideal LD50 values were correlated to those reported in the literature using Pearson’s correlation test for both intravenous and intraperitoneal routes of injection in rodents. Our results showed moderate correlations (r2=0.42 − 0.68, P<0.005–0.05) between the ideal LD50 values obtained using the CAM model with LD50 values from mice and rats models for both intravenous and intraperitoneal administrations, suggesting that the chick embryo may be a suitable alternative model for acute drug toxicity screening before embarking on full toxicological investigations in rodents in development of anticancer drugs. PMID:25736707

77 FR 46764 - Clinical Studies of Safety and Effectiveness of Orphan Products Research Project Grant (R01)

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-06

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2012-N-0011] Clinical Studies of Safety and Effectiveness of Orphan Products Research Project Grant (R01) AGENCY: Food... orphan products. Orphan products are drugs, biologics, medical devices, and medical foods that are...

Hunting for the function of orphan GPCRs – beyond the search for the endogenous ligand

PubMed Central

Ahmad, Raise; Wojciech, Stefanie; Jockers, Ralf

2015-01-01

Seven transmembrane-spanning proteins (7TM), also called GPCRs, are among the most versatile and evolutionary successful protein families. Out of the 400 non-odourant members identified in the human genome, approximately 100 remain orphans that have not been matched with an endogenous ligand. Apart from the classical deorphanization strategies, several alternative strategies provided recent new insights into the function of these proteins, which hold promise for high therapeutic potential. These alternative strategies consist of the phenotypical characterization of organisms silenced or overexpressing orphan 7TM proteins, the search for constitutive receptor activity and formation of protein complexes including 7TM proteins as well as the development of synthetic, surrogate ligands. Taken together, a variety of ligand-independent functions can be attributed to orphan 7TM proteins that range from constitutive activity to complex formation with other proteins and include ‘true’ orphans for which no ligand exist and ‘conditional’ orphans that behave like orphans in the absence of ligand and as non-orphans in the presence of ligand. PMID:25231237

Effects of raised CO2 concentration on the egg production rate and early development of two marine copepods (Acartia steueri and Acartia erythraea).

PubMed

Kurihara, Haruko; Shimode, Shinji; Shirayama, Yoshihisa

2004-11-01

Direct injection of CO(2) into the deep ocean is receiving increasing attention as a way to mitigate increasing atmospheric CO(2) concentration. To assess the potential impact of the environmental change associated with CO(2) sequestration in the ocean, we studied the lethal and sub-lethal effects of raised CO(2) concentration in seawater on adult and early stage embryos of marine planktonic copepods. We found that the reproduction rate and larval development of copepods are very sensitive to increased CO(2) concentration. The hatching rate tended to decrease, and nauplius mortality rate to increase, with increased CO(2) concentration. These results suggest that the marine copepod community will be negatively affected by the disposal of CO(2). This could decrease on the carbon export flux to the deep ocean and change the biological pump. Clearly, further studies are needed to determine whether ocean CO(2) injection is an acceptable strategy to reduce anthropogenic CO(2).

Effects of High Magneto-Gravitational Environment on Silkworm Embryogenesis

NASA Astrophysics Data System (ADS)

Tian, Zongcheng; Li, Muwang; Qian, Airong; Xu, Huiyun; Wang, Zhe; Di, Shengmeng; Yang, Pengfei; Hu, Lifang; Ding, Chong; Zhang, Wei; Luo, Mingzhi; Han, Jing; Gao, Xiang; Huang, Yongping; Shang, Peng

2010-04-01

The objective of this research was to observe whether silkworm embryos can survive in a high magneto-gravitational environment (HMGE) and what significant phenotype changes can be produced. The hatching rate, hatching time, life span, growth velocity and cocoon weight of silkworm were measured after silkworm embryos were exposed to HMGE (0 g, 12 T; 1 g, 16 T; and 2 g, 12 T) for a period of time. Compared with the control group, 0 g exposure resulted in a lower hatching rate and a shorter life span. Statistically insignificant morphological changes had been observed for larvae growth velocity, incidence of abnormal markings and weight of cocoons. These results suggest that the effect of HMGE on silkworm embryogenesis is not lethal. Bio-effects of silkworm embryogenesis at 0 g in a HMGE were similar with those of space flight. The hatching time, life span and hatching rates of silkworm may be potential phenotype markers related to exposure in a weightless environment.

Zebrafish embryo developmental toxicology assay.

PubMed

Panzica-Kelly, Julieta M; Zhang, Cindy X; Augustine-Rauch, Karen

2012-01-01

A promising in vitro zebrafish developmental toxicology assay was generated to test compounds for their teratogenic potential. The assay's predictivity is approximately 87% in AB strain fish (Brannen KC et al., Birth Defects Res B Dev Reprod Toxicol 89:66-77, 2010). The procedure entails exposing dechorionated gastrulation-stage embryos to a range of compound concentrations for 5 days throughout embryonic and larva development. The larvae are evaluated for viability in order to identify an LC25 (the compound concentration in which 25% lethality is observed) and morphological anomalies using a numerical score system to identify the NOAEL (no observed adverse effect level). These values are used to calculate the teratogenic index (LC25/NOAEL ratio) of each compound. If the teratogenic index is equal to or greater than 10 then the compound is classified as a teratogen, and if the ratio is less than 10 then the compound is classified as a nonteratogen (Brannen KC et al., Birth Defects Res B Dev Reprod Toxicol 89:66-77, 2010).

The zebrafish as a model system to study cardiovascular development.

PubMed

Stainier, D Y; Fishman, M C

1994-01-01

The zebrafish, Brachydanio rerio, is rapidly becoming a system of choice for vertebrate developmental biologists. It presents unique embryological attributes and is amenable to saturation style mutagenesis, a powerful approach that, in invertebrates, has already led to the identification of a large number of key developmental genes. Since fertilization is external, the zebrafish embryo develops in the dish and is thus accessible for continued observation and manipulation at all stages of development. Furthermore, because the embryo is transparent, the developing heart and vessels can be resolved at the single-cell level. A large number of mutations that affect the development of cardiovascular form and function have recently been isolated from large-scale genetic screens for zygotic embryonic lethals. Our further understanding of the development of the cardiovascular system is important not only because of the high incidence, and familial inheritance, of congenital abnormalities, but also because it should lead to novel, differentiation-based strategies for the analysis and therapy of the diseased state. Copyright © 1994. Published by Elsevier Inc.

The embryonic mouse hindbrain as a qualitative and quantitative model for studying the molecular and cellular mechanisms of angiogenesis.

PubMed

Fantin, Alessandro; Vieira, Joaquim M; Plein, Alice; Maden, Charlotte H; Ruhrberg, Christiana

2013-02-01

The mouse embryo hindbrain is a robust and adaptable model for studying sprouting angiogenesis. It permits the spatiotemporal analysis of organ vascularization in normal mice and in mouse strains with genetic mutations that result in late embryonic or perinatal lethality. Unlike postnatal models such as retinal angiogenesis or Matrigel implants, there is no requirement for the breeding of conditional knockout mice. The unique architecture of the hindbrain vasculature allows whole-mount immunolabeling of blood vessels and high-resolution imaging, as well as easy quantification of angiogenic sprouting, network density and vessel caliber. The hindbrain model also permits the visualization of ligand binding to blood vessels in situ and the analysis of blood vessel growth within a natural multicellular microenvironment in which endothelial cells (ECs) interact with non-ECs to refine the 3D organ architecture. The entire procedure, from embryo isolation to imaging and through to results analysis, takes approximately 4 d.

Drosophila neuroglian: a member of the immunoglobulin superfamily with extensive homology to the vertebrate neural adhesion molecule L1.

PubMed

Bieber, A J; Snow, P M; Hortsch, M; Patel, N H; Jacobs, J R; Traquina, Z R; Schilling, J; Goodman, C S

1989-11-03

Drosophila neuroglian is an integral membrane glycoprotein that is expressed on a variety of cell types in the Drosophila embryo, including expression on a large subset of glial and neuronal cell bodies in the central and peripheral nervous systems and on the fasciculating axons that extend along them. Neuroglian cDNA clones were isolated by expression cloning. cDNA sequence analysis reveals that neuroglian is a member of the immunoglobulin superfamily. The extracellular portion of the protein consists of six immunoglobulin C2-type domains followed by five fibronectin type III domains. Neuroglian is closely related to the immunoglobulin-like vertebrate neural adhesion molecules and, among them, shows most extensive homology to mouse L1. Its homology to L1 and its embryonic localization suggest that neuroglian may play a role in neural and glial cell adhesion in the developing Drosophila embryo. We report here on the identification of a lethal mutation in the neuroglian gene.

[Authorization and reimbursement of orphan drugs in an international comparison].

PubMed

Roll, K; Stargardt, T; Schreyögg, J

2011-08-01

This paper analyses schemes to promote the authorisation of and reimbursement for orphan drugs. 8 countries - Australia, Canada, Germany, Great Britain, France, Netherlands, Switzerland, USA - were studied to compare specific regulations for orphan drugs regarding drug admission, health technology assessment (HTA), decision-making for reimbursement, and off-label and compassionate use. Information was obtained by reviewing published and grey literature. Expert interviews were also conducted. The comparison of orphan drug legislation reveals that the EU and the USA offer the greatest incentives for the development of orphan drugs, whereas there is a tendency for Australia and Switzerland to profit from incentives in other countries. Although not explicitly stated, economic evaluation of orphan drugs takes the special circumstances for orphan drugs into account. In addition to common reimbursement practices, special schemes or programmes for the reimbursement of high-priced orphan drugs exist in all countries that were analysed. Therefore access to orphan drugs seems to be warranted. However, due to co-payments of 5%, the USA may form an exception. On the one hand, the use of special criteria for drug admission, HTA, and reimbursement promotes R&D for orphan drugs. On the other hand, high opportunity costs arise, because huge efforts are made for a minority of patients. A solution for this moral dilemma may be the application of "rule of rescue" or of "no cure, no pay" programmes. © Georg Thieme Verlag KG Stuttgart · New York.

Children, AIDS and the politics of orphan care in Ethiopia: the extended family revisited.

PubMed

Abebe, Tatek; Aase, Asbjorn

2007-05-01

The astounding rise in the number of orphans due to the HIV/AIDS epidemic has left many Ethiopian families and communities with enormous childcare problems. Available studies on the capacity and sustainability of the extended family system, which culturally performs the role of care for children in need, suggest two competing theories. The first is grounded in the social rupture thesis and assumes that the traditional system of orphan care is stretched by the impact of the epidemic, and is actually collapsing. By contrast, the second theory counter-suggests that the flexibility and strength of the informal childcare practise, if supported by appropriate interventions, can still support a large number of orphans. Based on a seven-month period of child-focused, qualitative research fieldwork in Ethiopia involving observations; in-depth interviews with orphans (42), social workers (12) and heads of households (18); focus group discussions with orphans (8), elderly people and community leaders (6); and story-writing by children in school contexts, this article explores the trade-offs and social dynamics of orphan care within extended family structures in Ethiopia. It argues that there is a rural-urban divide in the capacity to cater for orphans that emanates from structural differences as well as the socio-cultural and economic values associated with children. The care of orphans within extended family households is also characterised by multiple and reciprocal relationships in care-giving and care-receiving practices. By calling for a contextual understanding of the 'orphan burden', the paper concludes that interventions for orphans may consider care as a continuum in the light of four profiles of extended families, namely rupturing, transient, adaptive, and capable families.

Survival, family conditions and nutritional status of motherless orphans in the West Bank, Palestine.

PubMed

Al-Adili, Nadim; Shaheen, Mohammad; Bergstrom, Staffan; Johansson, Annika

2008-05-01

This study describes survival, family care and growth of the orphans of women dying at reproductive age (15-49 years) in the West Bank, Palestine, in 2000 and 2001. One hundred and sixty-seven children who were below 5 years of age at the time of the mother's death were identified. Three had died soon after birth. The family situation for the remaining 164 children was recorded. A planned baseline study could not be done at that time, due to the escalating political violence in the study area. In 2004, an average of 3 years after the mother's death, all orphan families were contacted. Of the 164 orphans, six had left the country with their fathers, and six could not be reached, due to restricted mobility. Home interviews were conducted with the 148 orphans' custodians/care-takers. Family situation and orphans' health status as judged by the interviewees were investigated, and are presented in descriptive statistics. Orphan weight and height were measured, and rates of wasting and stunting were calculated and analysed by gender. The most striking finding is the high survival rate among the orphans. With the exception of the three neonatal deaths, all orphans who could be reached were alive. Almost all lived with their fathers, most of whom had remarried shortly after the death of their wives, and a stepmother had joined the family in 85% of the cases. Of the orphans under 5 years of age at the time of the interview, 8.8% and 17.6%, respectively, suffered from wasting and stunting, all of whom were girls. These rates were higher than those in the national data from 2003 for Palestinian children. Early family reconstruction is suggested to be a contributing factor to the high survival rate. Close monitoring of motherless orphans' health and nutritional status, with a special emphasis on orphan girls, should be ensured.

Does the Orphan Disadvantage “Spill Over?” An analysis of whether living in an area with a higher concentration of orphans is associated with children’s school enrollment in sub-Saharan Africa

PubMed Central

Smith-Greenaway, Emily; Heckert, Jessica

2013-01-01

BACKGROUND Despite considerable concern regarding the social consequences of sub-Saharan Africa’s high orphan prevalence, no research investigates how living in a community densely populated with orphans is more broadly associated with children’s—including nonorphans’—acquisition of human capital. OBJECTIVE We provide a new look at the implications of widespread orphanhood in sub-Saharan Africa by examining whether living in an area with a high concentration of orphans is associated with children’s likelihood of school enrollment. METHODS We use data from the Demographic and Health Survey (DHS) and the Multiple Indicators Cluster Survey (MICS) to estimate multilevel logistic regression models to assess whether living in a setting with a higher concentration of orphans is associated with school enrollment among 383,010 children in 336 provinces in 34 sub-Saharan African countries. RESULTS Orphan concentration has a curvilinear association with children’s school enrollment in western and eastern Africa: the initially positive association becomes negative at higher levels. In central and southern Africa, orphan concentration has a positive linear association with children’s school enrollment. CONCLUSION In western and eastern Africa, the negative association between living in a setting more densely populated with orphans and children’s school enrollment provides suggestive evidence that the orphan disadvantage “spills over” in the communities most heavily affected. Conversely, in central and southern Africa, the positive association between living in a setting more densely populated with orphans and children’s school enrollment highlights the resiliency of these relatively wealthier communities with high levels of orphans. Although longitudinal research is needed to confirm these findings and clarify the underlying mechanisms, this study lays the groundwork for a new body of research aimed at understanding the broader social implications of widespread orphanhood in sub-Saharan Africa. PMID:24062628

From novice to expert: agroecological competences of children orphaned by AIDS compared to non-orphans in Benin

PubMed Central

2011-01-01

Background AIDS has created new vulnerabilities for rural African households due to prime-age adult mortality and is assumed to lead to impairment of the intergenerational transfer of farming knowledge. There has been scant research to date, however, on the impacts of parental death on farming knowledge of children made orphans by AIDS. The question we investigate is if there is a difference in agricultural expertise between AIDS affected and non-affected adults and children. Methods The research was carried out in rural Benin with 77 informants randomly selected according to their AIDS status: 13 affected and 13 non-affected adults; 13 paternal, 13 maternal and 13 double orphans; and 12 non-orphan children. Informants descriptions from pile sorting exercises of maize and cowpea pests were categorized and then aggregated into descriptions based form (morphology) and function (utility) and used to determine whether the moving from novice to expert is impaired by children orphaned by AIDS. Differences and similarities in responses were determined using the Fischer exact test and the Cochran-Mantzel-Haenszel test. Results No significant differences were found between AIDS affected and non-affected adults. Results of the study do reveal differences in the use of form and function descriptors among the children. There is a statistically significant difference in the use of form descriptors between one-parent orphans and non-orphans and in descriptors of specific damages to maize. One-parent paternal orphans were exactly like non-affected adults in their 50/50 balanced expertise in the use of both form and function descriptors. One-parent orphans also had the highest number of descriptors used by children overall and these descriptors are spread across the various aspects of the knowledge domain relative to non-orphans. Conclusions Rather than a knowledge loss for one-parent orphans, particularly paternal orphans, we believe we are witnessing acceleration into adult knowledge frames. This expertise of one-parent orphans may be a result of a combination of factors deserving further investigation including enhanced hands-on work experience with the food crops in the field and the expertise available from the surviving parent coupled with the value of the food resource to the household. PMID:21219626

The orphan receptor Rev-erbα gene is a target of the circadian clock pacemaker

PubMed Central

Triqueneaux, Gérard; Thenot, Sandrine; Kakizawa, Tomoko; Antoch, Marina P; Safi, Rachid; Takahashi, Joseph S; Delaunay, Franck; Laudet, Vincent

2013-01-01

Rev-erbα is a ubiquitously expressed orphan nuclear receptor which functions as a constitutive transcriptional repressor and is expressed in vertebrates according to a robust circadian rhythm. We report here that two Rev-erbα mRNA isoforms, namely Rev-erbα1 and Rev-erbα2, are generated through alternative promoter usage and that both show a circadian expression pattern in an in vitro system using serum-shocked fibroblasts. Both promoter regions P1 (Rev-erbα1) and P2 (Rev-erbα2) contain several E-box DNA sequences, which function as response elements for the core circadian-clock components: CLOCK and BMAL1. The CLOCK–BMAL1 heterodimer stimulates the activity of both P1 and P2 promoters in transient transfection assay by 3–6-fold. This activation was inhibited by the overexpression of CRY1, a component of the negative limb of the circadian transcriptional loop. Critical E-box elements were mapped within both promoters. This regulation is conserved in vertebrates since we found that the CLOCK–BMAL1 heterodimer also regulates the zebrafish Rev-erbα gene. In line with these data Rev-erbα circadian expression was strongly impaired in the livers of Clock mutant mice and in the pineal glands of zebrafish embryos treated with Clock and Bmal1 antisense oligonucleotides. Together these data demonstrate that CLOCK is a critical regulator of Rev-erbα circadian gene expression in evolutionarily distant vertebrates and suggest a role for Rev-erbα in the circadian clock output. PMID:15591021

A Complex Extracellular Sphingomyelinase of Pseudomonas aeruginosa Inhibits Angiogenesis by Selective Cytotoxicity to Endothelial Cells

PubMed Central

Vasil, Michael L.; Stonehouse, Martin J.; Vasil, Adriana I.; Wadsworth, Sandra J.; Goldfine, Howard; Bolcome, Robert E.; Chan, Joanne

2009-01-01

The hemolytic phospholipase C (PlcHR) expressed by Pseudomonas aeruginosa is the original member of a Phosphoesterase Superfamily, which includes phosphorylcholine-specific phospholipases C (PC-PLC) produced by frank and opportunistic pathogens. PlcHR, but not all its family members, is also a potent sphingomyelinase (SMase). Data presented herein indicate that picomolar (pM) concentrations of PlcHR are selectively lethal to endothelial cells (EC). An RGD motif of PlcHR contributes to this selectivity. Peptides containing an RGD motif (i.e., GRGDS), but not control peptides (i.e., GDGRS), block the effects of PlcHR on calcium signaling and cytotoxicity to EC. Moreover, RGD variants of PlcHR (e.g., RGE, KGD) are significantly reduced in their binding and toxicity, but retain the enzymatic activity of the wild type PlcHR. PlcHR also inhibits several EC-dependent in vitro assays (i.e., EC migration, EC invasion, and EC tubule formation), which represent key processes involved in angiogenesis (i.e., formation of new blood vessels from existing vasculature). Finally, the impact of PlcHR in an in vivo model of angiogenesis in transgenic zebrafish, and ones treated with an antisense morpholino to knock down a key blood cell regulator, were evaluated because in vitro assays cannot fully represent the complex processes of angiogenesis. As little as 2 ng/embryo of PlcHR was lethal to ∼50% of EGFP-labeled EC at 6 h after injection of embryos at 48 hpf (hours post-fertilization). An active site mutant of PlcHR (Thr178Ala) exhibited 120-fold reduced inhibitory activity in the EC invasion assay, and 20 ng/embryo elicited no detectable inhibitory activity in the zebrafish model. Taken together, these observations are pertinent to the distinctive vasculitis and poor wound healing associated with P. aeruginosa sepsis and suggest that the potent antiangiogenic properties of PlcHR are worthy of further investigation for the treatment of diseases where angiogenesis contributes pathological conditions (e.g., vascularization of tumors, diabetic retinopathy). PMID:19424430

Thirty Years of Orphan Drug Legislation and the Development of Drugs to Treat Rare Seizure Conditions: A Cross Sectional Analysis.

PubMed

Döring, Jan Henje; Lampert, Anette; Hoffmann, Georg F; Ries, Markus

2016-01-01

Epilepsy is a serious chronic health condition with a high morbidity impairing the life of patients and afflicted families. Many epileptic conditions, especially those affecting children, are rare disorders generating an urgent medical need for more efficacious therapy options. Therefore, we assessed the output of the US and European orphan drug legislations. Quantitative analysis of the FDA and EMA databases for orphan drug designations according to STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) criteria. Within the US Orphan Drug Act 40 designations were granted delivering nine approvals, i.e. clobazam, diazepam viscous solution for rectal administration, felbamate, fosphenytoin, lamotrigine, repository corticotropin, rufinamide, topiramate, and vigabatrin. Since 2000 the EMA granted six orphan drug designations whereof two compounds were approved, i.e. rufinamide and stiripentol. In the US, two orphan drug designations were withdrawn. Orphan drugs were approved for conditions including Lennox-Gastaut syndrome, infantile spasms, Dravet syndrome, and status epilepticus. Comparing time to approval for rufinamide, which was approved in the US and the EU to treat rare seizure conditions, the process seems faster in the EU (2.2 years) than in the US (4.3 years). Orphan drug development in the US and in the EU delivered only few molecular entities to treat rare seizure disorders. The development programs focused on already approved antiepileptic drugs or alternative pharmaceutical formulations. Most orphan drugs approved in the US are not approved in the EU to treat rare seizures although some were introduced after 2000 when the EU adopted the Orphan Drug Regulation.

Extended family caring for children orphaned by AIDS: balancing essential work and caregiving in a high HIV prevalence nations.

PubMed

Heymann, J; Earle, A; Rajaraman, D; Miller, C; Bogen, K

2007-03-01

While over 90 per cent of the 15 million children who have been orphaned by HIV/AIDS are cared for by family members, there is little information about whether adults can meet orphans' essential caregiving needs while working to economically survive. Using a survey we conducted in Botswana of 1033 working adults, we analyse the experience of adults who are caring for orphans. Over one-third of working adults were caring for orphans and many with few financial resources: 82% were living on household incomes below US$10 purchasing power parity adjusted per person per day. Because of their caregiving responsibilities, they were less able to supplement income with overtime, weekend, evening, or night work. At the same time caregiving responsibilities meant orphan caregivers spent fewer hours caring for their own children and other family members. Nearly half of orphan caregivers had difficulties meeting their children's needs, and nearly 75% weren't able to meet with children's teachers. Pay loss at work compounded the problems: One-quarter of orphan caregivers reported having to take unpaid leave to meet sick childcare needs and nearly half reported being absent from work for children's routine health care. This paper makes clear that if families are to provide adequate care for orphans while economically surviving there needs to be increases in social supports and improvements in working conditions.

Accessing Social Grants to Meet Orphan Children School Needs: Namibia and South Africa Perspective

ERIC Educational Resources Information Center

Taukeni, Simon; Matshidiso, Taole

2013-01-01

In this comparative paper we interrogate the access of social grants to meet orphan children school needs in Namibia and South Africa. We noted that the two governments are committed to provide orphan children with social grants to enable them to meet the school needs. However, accessing social grant to benefit most vulnerable orphan children…

Exploring Responses to Transformative Group Therapy for Orphaned Children in the Context of Mass Orphaning in Botswana

ERIC Educational Resources Information Center

Thamuku, Masego; Daniel, Marguerite

2013-01-01

In the context of AIDS, the Botswana Government has adopted a group therapy program to help large numbers of orphaned children cope with bereavement. This study explores the effectiveness of the therapy and examines how it interacts with cultural attitudes and practices concerning death. Ten orphaned children were involved in five rounds of data…

Longitudinal evaluation of the psychosocial wellbeing of recent orphans compared with non-orphans in a school-attending cohort in KwaZulu-Natal, South Africa

PubMed Central

Bachman DeSilva, Mary; Skalicky, Anne M.; Beard, Jennifer; Cakwe, Mandisa; Zhuwau, Tom; Simon, Jonathon L.

2013-01-01

To assess differences in psychosocial wellbeing between recent orphans and non-orphans, we followed a cohort of 157 school-going orphans and 480 non-orphans ages 9-15 in a context of high HIV/AIDS mortality in South Africa from 2004 to 2007. Several findings were contrary to published evidence to date, as we found no difference between orphans and non-orphans in anxiety/depression symptoms, oppositional behavior, self-esteem, or resilience. Female gender, self-reported poor health, and food insecurity were the most important predictors of children’s psychosocial wellbeing. Notably, girls had greater odds of reporting anxiety/depression symptoms than boys, and scored lower on self-esteem and resilience scales. Food insecurity predicted greater anxiety/depression symptoms and lower resilience. Perceived social support was a protective factor, as it was associated with lower odds of anxiety/depression symptoms, lower oppositional scores, and greater self-esteem and resilience. Our findings suggest a need to identify and strengthen psychosocial supports for girls, and for all children in contexts of AIDS-affected and economic adversity. PMID:23457424

[Hope for patients with rare diseases--"orphan" drugs].

PubMed

Kuzelová, M; Kubácková, K; Palágyi, M; Smíd, M

2006-01-01

Rare diseases are defined as those affected less than five in every 10 000 person in European Union. The purpose of this paper is to present activities, which make possible to stimulate research development and marketing of appropriate medicine for tretment of rare disease, named "Orphan" medicinal products. EU "Orphan" medicinal products legislation which entered into force in April 2000 is described. Definition of "Orphan" medicinal products as well as the procedure of designation and placing the products into the Community register is presented. Those incentives to industry are described, which are already five years very well implemented oh the European level mostly on the pre-authorisation phase of "Orphan" medicinal products development, but also in the registration process as well as the post-authorisation phase. Finaly, the first twenty "Orphan" medicinal products, which have been given positive opinion in the Community for the grant of a marketing authorisation till April 2005 are mentioned in this work. The real availability of "Orphan" medicinal products in the particular EU member states is analysed.

Orphan drug development: an economically viable strategy for biopharma R&D.

PubMed

Meekings, Kiran N; Williams, Cory S M; Arrowsmith, John E

2012-07-01

Orphan drug incentives have stimulated research into diseases with significant unmet medical need. Although the targeting of orphan diseases is seen by industry as an attractive strategy, there are limited economic data available to support its use. In this paper we show that the revenue-generating potential of orphan drugs is as great as for non-orphan drugs, even though patient populations for rare diseases are significantly smaller. Moreover, we suggest that orphan drugs have greater profitability when considered in the full context of developmental drivers including government financial incentives, smaller clinical trial sizes, shorter clinical trial times and higher rates of regulatory success. The data support the targeting of rare diseases as an important component of a successful biopharma R&D strategy. Copyright © 2012 Elsevier Ltd. All rights reserved.

An ultra-HTS process for the identification of small molecule modulators of orphan G-protein-coupled receptors.

PubMed

Cacace, Angela; Banks, Martyn; Spicer, Timothy; Civoli, Francesca; Watson, John

2003-09-01

G-protein-coupled receptors (GPCRs) are the most successful target proteins for drug discovery research to date. More than 150 orphan GPCRs of potential therapeutic interest have been identified for which no activating ligands or biological functions are known. One of the greatest challenges in the pharmaceutical industry is to link these orphan GPCRs with human diseases. Highly automated parallel approaches that integrate ultra-high throughput and focused screening can be used to identify small molecule modulators of orphan GPCRs. These small molecules can then be employed as pharmacological tools to explore the function of orphan receptors in models of human disease. In this review, we describe methods that utilize powerful ultra-high-throughput screening technologies to identify surrogate ligands of orphan GPCRs.

The Burden of Orphans and Vulnerable Children Due to HIV/AIDS in Cameroon

PubMed Central

Nsagha, Dickson S; Bissek, Anne-Cécile ZK; Nsagha, Sarah M; Assob, Jules-Clement N; Kamga, Henri-Lucien F; Njamnshi, Dora M; Njunda, Anna L; Obama, Marie-Thérèse O; Njamnshi, Alfred K

2012-01-01

HIV/AIDS is a major public health problem in Cameroon and Africa, and the challenges of orphans and vulnerable children are a threat to child survival, growth and development. The HIV prevalence in Cameroon was estimated at 5.1% in 2010. The objective of this study was to assess the burden of orphans and vulnerable children due to HIV/AIDS in Cameroon. A structured search to identify publications on orphans and other children made vulnerable by AIDS was carried out. A traditional literature search on google, PubMed and Medline using the keywords: orphans, vulnerable children, HIV/AIDS and Cameroon was conducted to identify potential AIDS orphans publications, we included papers on HIV prevalence in Cameroon, institutional versus integrated care of orphans, burden of children orphaned by AIDS and projections, impact of AIDS orphans on Cameroon, AIDS orphans assisted through the integrated care approach, and comparism of the policies of orphans care in the central African sub-region. We also used our participatory approach working experience with traditional rulers, administrative authorities and health stakeholders in Yaounde I and Yaounde VI Councils, Nanga Eboko Health District, Isangelle and Ekondo Titi Health Areas, Bafaka-Balue, PLAN Cameroon, the Pan African Institute for Development-West Africa, Save the orphans Foundation, Ministry of Social Affairs, and the Ministry of Public Health. Results show that only 9% of all OVC in Cameroon are given any form of support. AIDS death continue to rise in Cameroon. In 1995, 7,900 people died from AIDS in the country; and the annual number rose to 25,000 in 2000. Out of 1,200,000 orphans and vulnerable children in Cameroon in 2010, 300,000(25%) were AIDS orphans. Orphans and the number of children orphaned by AIDS has increased dramatically from 13,000 in 1995 to 304,000 in 2010. By 2020, this number is projected to rise to 350,000. These deaths profoundly affect families, which often are split up and left without any means of support. Similarly, the death of many people in their prime working years hamper the economy. Businesses are adversely affected due to the need to recruit and train new staff. Health and social service systems suffer from the loss of health workers, teachers, and other skilled workers. OVC due to HIV/AIDS are a major public health problem in Cameroon as the HIV prevalence continues its relentless increase with 141 new infections per day. In partnership with the Ministry of Social Affairs and other development organizations, the Ministry of Public Health has been striving hard to provide for the educational and medical needs of the OVC, vocational training for the out-of- school OVC and income generating activities for foster families and families headed by children. A continous multi-sectorial approach headed by the government to solve the problem of OVC due to AIDS is very important. In line with the foregoing, recommendations are proposed for the way forward. PMID:23248738

Developmental disorders in embryos of the frog Xenopus laevis induced by chloroacetanilide herbicides and their degradation products.

PubMed

Osano, Odipo; Admiraal, Wim; Otieno, Dismas

2002-02-01

Pesticides are known to transform in the environment, but so far the study of their effects in the environment has concentrated on the parent compounds, thereby neglecting the effects of the degradation products. The embryotoxic, developmental, and teratogenic effects of chloroacetanilide herbicides and their environmentally stable aniline degradation products were investigated in this study in view of the massive application of alachlor and metolachlor. Embryos at midblastula to early gastrula stages of a locally abundant African clawed frog Xenopus laevis were used as test organisms. The embryos were exposed to the test chemicals for 96 h in each experiment. Alachlor is more embryotoxic (the concentration causing 50% embryo lethality, 96-h LC50 = 23 microM [6.1 mg/L]) and teratogenic (teratogenic index [TI] = 1.7) than metolachlor (96-h LC50 = 48 microM [13.6 mg/L], TI = 0.2). The degradation products of alachlor and metolachlor, respectively, 2,6-diethylaniline (96-h LC50 = 13 microM [19.4 mg/L], TI = 2.1) and 2-ethyl-6-methyaniline (96-h LC50 = 509 microM [68.8 mg/L], TI = 2.7), are less embryotoxic but more teratogenic than their parent compounds. The most common teratogenic effects observed were edema for alachlor as opposed to axial flexures and eye abnormalities for 2,6-diethylaniline and 2-ethyl-6-methylaniline. Metolachlor is found to be an example of a nonteratogenic herbicide that upon degradation loses toxicity but gains teratogenicity, and both the herbicides, metolachlor and alachlor, are potential sources of teratogenic transformation products.

TopBP1 deficiency causes an early embryonic lethality and induces cellular senescence in primary cells.

PubMed

Jeon, Yoon; Ko, Eun; Lee, Kyung Yong; Ko, Min Ji; Park, Seo Young; Kang, Jeeheon; Jeon, Chang Hwan; Lee, Ho; Hwang, Deog Su

2011-02-18

TopBP1 plays important roles in chromosome replication, DNA damage response, and other cellular regulatory functions in vertebrates. Although the roles of TopBP1 have been studied mostly in cancer cell lines, its physiological function remains unclear in mice and untransformed cells. We generated conditional knock-out mice in which exons 5 and 6 of the TopBP1 gene are flanked by loxP sequences. Although TopBP1-deficient embryos developed to the blastocyst stage, no homozygous mutant embryos were recovered at E8.5 or beyond, and completely resorbed embryos were frequent at E7.5, indicating that mutant embryos tend to die at the peri-implantation stage. This finding indicated that TopBP1 is essential for cell proliferation during early embryogenesis. Ablation of TopBP1 in TopBP1(flox/flox) mouse embryonic fibroblasts and 3T3 cells using Cre recombinase-expressing retrovirus arrests cell cycle progression at the G(1), S, and G(2)/M phases. The TopBP1-ablated mouse cells exhibit phosphorylation of H2AX and Chk2, indicating that the cells contain DNA breaks. The TopBP1-ablated mouse cells enter cellular senescence. Although RNA interference-mediated knockdown of TopBP1 induced cellular senescence in human primary cells, it induced apoptosis in cancer cells. Therefore, TopBP1 deficiency in untransformed mouse and human primary cells induces cellular senescence rather than apoptosis. These results indicate that TopBP1 is essential for cell proliferation and maintenance of chromosomal integrity.

Effects of metal exposure on motor neuron development, neuromasts and the escape response of zebrafish embryos.

PubMed

Sonnack, Laura; Kampe, Sebastian; Muth-Köhne, Elke; Erdinger, Lothar; Henny, Nicole; Hollert, Henner; Schäfers, Christoph; Fenske, Martina

2015-01-01

Low level metal contaminations are a prevalent issue with often unknown consequences for health and the environment. Effect-based, multifactorial test systems with zebrafish embryos to assess in particular developmental toxicity are beneficial but rarely used in this context. We therefore exposed wild-type embryos to the metals copper (CuSO4), cadmium (CdCl2) and cobalt (CoSO4) for 72 h to determine lethal as well as sublethal morphological effects. Motor neuron damage was investigated by immunofluorescence staining of primary motor neurons (PMNs) and secondary motor neurons (SMNs). In vivo stainings using the vital dye DASPEI were used to quantify neuromast development and damage. The consequences of metal toxicity were also assessed functionally, by testing fish behavior following tactile stimulation. The median effective concentration (EC50) values for morphological effects 72 h post fertilization (hpf) were 14.6 mg/L for cadmium and 0.018 mg/L for copper, whereas embryos exposed up to 45.8 mg/L cobalt showed no morphological effects. All three metals caused a concentration-dependent reduction in the numbers of normal PMNs and SMNs, and in the fluorescence intensity of neuromasts. The results for motor neuron damage and behavior were coincident for all three metals. Even the lowest metal concentrations (cadmium 2mg/L, copper 0.01 mg/L and cobalt 0.8 mg/L) resulted in neuromast damage. The results demonstrate that the neuromast cells were more sensitive to metal exposure than morphological traits or the response to tactile stimulation and motor neuron damage. Copyright © 2015 Elsevier Inc. All rights reserved.

Acute and early life stage toxicity of industrial effluent on Japanese medaka (Oryzias latipes).

PubMed

Zha, Jinmiao; Wang, Zijian

2006-03-15

To develop the whole effluent toxicity testing methods (WET), embryo larval stage toxicity test using Japanese medaka (Oryzias latipes) was conducted to evaluate an effluent from a banknote printing plant (BPP). The method is based on acute toxicity using endpoint of 96-h larval morality and on chronic toxicity using endpoints such as the time to hatch, hatching success, deformity, growth rate, swim-up failure, accumulative mortality and sexual ratio. In test for 96-h larval mortality, LC50 (the concentration was lethal to 50% of newly hatching medaka larvae) was 72.9%. In chronic toxicity test, newly fertilized embryos (<5-h old) were exposed to 1%, 6.25%, 12.5%, 25%, 50% effluent concentrations and to 200 mug/l BPA in a 24-h static renewal system at 25+/-1 degrees C until 15 day post-hatch. The results showed that all chronic endpoints were significantly different from the control at 50% dilution (p < 0.01). Embryos began to show lesions on 4th day at higher concentrations (12.5%, 25%, 50% BPP effluent concentrations). Treatment group of 25% dilution showed delayed time to hatch. A reduction in body weight was observed at 25% dilutions for males and females, respectively. Deformities were observed in newly hatched larvae at 25% and 50% BPP effluent concentrations. At 25% dilution, sex ratio of larvae was alternated and there was feminization phenomenon. We conclude that embryo larval stage test using medaka is feasible to evaluate both acute and chronic toxicities and potential endocrine disrupting activity of industrial effluents.

Enriching Orphans' Potentials through Interpersonal and Intrapersonal Intelligence Enrichment Activities

ERIC Educational Resources Information Center

Azid, Nurulwahida Hj; Yaacob, Aizan

2016-01-01

Orphans are considered a minority and they should be given a greater emphasis so that they do not feel left out and can build their own lives without a sense of humility. This does not mean that the orphans should be pampered instead they should be given the confidence and motivation to strive for success in later life. Humility among orphans can…

The Self-Concept and Academic Performance of Institutionalized and Non-Institutionalized HIV/AIDS Orphaned Children in Kisumu Municipality

ERIC Educational Resources Information Center

Kimani, Chege Gabriel; Cheboswony, M.; Kodero, H. M.; Misigo, Benard L.

2009-01-01

The HIV/AIDS pandemic has increasingly become a major factor in the emergence of orphans in the developing countries. These orphans are usually traumatized due to the multiple losses, isolation, stigma and grief. The study sought to investigate the effect of institutionalization of children on the self-concept of the AIDS-orphaned children and to…

Profiling the orphan enzymes

PubMed Central

2014-01-01

The emergence of Next Generation Sequencing generates an incredible amount of sequence and great potential for new enzyme discovery. Despite this huge amount of data and the profusion of bioinformatic methods for function prediction, a large part of known enzyme activities is still lacking an associated protein sequence. These particular activities are called “orphan enzymes”. The present review proposes an update of previous surveys on orphan enzymes by mining the current content of public databases. While the percentage of orphan enzyme activities has decreased from 38% to 22% in ten years, there are still more than 1,000 orphans among the 5,000 entries of the Enzyme Commission (EC) classification. Taking into account all the reactions present in metabolic databases, this proportion dramatically increases to reach nearly 50% of orphans and many of them are not associated to a known pathway. We extended our survey to “local orphan enzymes” that are activities which have no representative sequence in a given clade, but have at least one in organisms belonging to other clades. We observe an important bias in Archaea and find that in general more than 30% of the EC activities have incomplete sequence information in at least one superkingdom. To estimate if candidate proteins for local orphans could be retrieved by homology search, we applied a simple strategy based on the PRIAM software and noticed that candidates may be proposed for an important fraction of local orphan enzymes. Finally, by studying relation between protein domains and catalyzed activities, it appears that newly discovered enzymes are mostly associated with already known enzyme domains. Thus, the exploration of the promiscuity and the multifunctional aspect of known enzyme families may solve part of the orphan enzyme issue. We conclude this review with a presentation of recent initiatives in finding proteins for orphan enzymes and in extending the enzyme world by the discovery of new activities. Reviewers This article was reviewed by Michael Galperin, Daniel Haft and Daniel Kahn. PMID:24906382

Profiling the orphan enzymes.

PubMed

Sorokina, Maria; Stam, Mark; Médigue, Claudine; Lespinet, Olivier; Vallenet, David

2014-06-06

The emergence of Next Generation Sequencing generates an incredible amount of sequence and great potential for new enzyme discovery. Despite this huge amount of data and the profusion of bioinformatic methods for function prediction, a large part of known enzyme activities is still lacking an associated protein sequence. These particular activities are called "orphan enzymes". The present review proposes an update of previous surveys on orphan enzymes by mining the current content of public databases. While the percentage of orphan enzyme activities has decreased from 38% to 22% in ten years, there are still more than 1,000 orphans among the 5,000 entries of the Enzyme Commission (EC) classification. Taking into account all the reactions present in metabolic databases, this proportion dramatically increases to reach nearly 50% of orphans and many of them are not associated to a known pathway. We extended our survey to "local orphan enzymes" that are activities which have no representative sequence in a given clade, but have at least one in organisms belonging to other clades. We observe an important bias in Archaea and find that in general more than 30% of the EC activities have incomplete sequence information in at least one superkingdom. To estimate if candidate proteins for local orphans could be retrieved by homology search, we applied a simple strategy based on the PRIAM software and noticed that candidates may be proposed for an important fraction of local orphan enzymes. Finally, by studying relation between protein domains and catalyzed activities, it appears that newly discovered enzymes are mostly associated with already known enzyme domains. Thus, the exploration of the promiscuity and the multifunctional aspect of known enzyme families may solve part of the orphan enzyme issue. We conclude this review with a presentation of recent initiatives in finding proteins for orphan enzymes and in extending the enzyme world by the discovery of new activities.

Health of adults caring for orphaned children in an HIV-endemic community in South Africa.

PubMed

Kuo, Caroline; Operario, Don

2011-09-01

In South Africa, an estimated 2.5 million children have been orphaned by AIDS and other causes of adult mortality. Although there is a growing body of research on the well-being of South African orphaned children, few research studies have examined the health of adult individuals caring for children in HIV-endemic communities. The cross-sectional survey assessed prevalence of general health and functioning (based on Short-Form 36 version 2 scale), depression (based on Center for Epidemiologic Studies-Depression scale), anxiety (using Kessler-10 scale), and post-traumatic stress (using the Harvard Trauma Questionnaire) among a representative community sample of adults caring for children in Umlazi Township, an HIV-endemic community in South Africa. Of 1599 respondents, 33% (n=530) were carers of orphaned children. Results showed that, overall, carers reported poor general health and functioning and elevated levels of depression, anxiety, and post-traumatic stress. Carers of orphaned children reported significantly poorer general health and functioning and higher rates of depression and post-traumatic stress compared with carers of non-orphaned children. In multivariate analyses, orphan carer and non-orphan carer differences in general health were accounted for by age, gender, education, economic assets, and source of income, but differences in depression were independent of these cofactors. Interventions are needed to address physical and mental health of carers in general. Greater health problems among orphan carers appeared to be fully explained by socioeconomic characteristics, which offer opportunities for targeting of programs. More research is needed to understand determinants of mental health disparities among orphan carers, which were not explained by socioeconomic characteristics.

Understanding orphan and non-orphan adolescents' sexual risks in the context of poverty: a qualitative study in Nyanza Province, Kenya.

PubMed

Juma, Milka; Alaii, Jane; Bartholomew, L Kay; Askew, Ian; Van den Born, Bart

2013-07-25

Some studies show orphanhood to be associated with increased sexual risk-taking while others have not established this relationship, but have found factors other than orphanhood as predictors of sexual risk behaviours and outcomes among adolescents. This study examines community members' perceptions of how poverty influences adolescent sexual behaviour and outcomes in four districts of Nyanza Province, Kenya. Eight study sites within the four districts were randomly selected. Focus group discussions were conducted with a purposive sample of adolescents, parents and caregivers. Key informant interviews were undertaken with a purposive sample of community leaders, child welfare and healthcare workers, and adolescents. The two methods elicited information on factors perceived to predispose adolescent orphans and non-orphans to sexual risks. Data were analysed through line-by-line coding, grouped into families and retrieved as themes and sub-themes. Participants included 147 adolescents and parents/caregivers in 14 focus groups and 13 key informants. Poverty emerged as a key predisposing factor to sexual risk behaviour among orphans and non-orphans. Poverty was associated with lack of food, poor housing, school dropout, and engaging in income generating activities, all of which increase their vulnerability to transactional sex, early marriage, sexual experimentation, and the eventual consequences of increased risk of unintended pregnancies and STI/HIV. Poverty was perceived to contribute to increasing sexual risks among orphan and non-orphan adolescents through survival strategies adopted to be able to meet their basic needs. Policies for prevention and intervention that target adolescents in a generalized poverty and HIV epidemic should integrate economic empowerment for caregivers and life skills for adolescents to reduce vulnerabilities of orphan and non-orphan adolescents to sexual risk behaviour.

Health of adults caring for orphaned children in an HIV endemic community in South Africa

PubMed Central

Kuo, Caroline; Operario, Don

2011-01-01

In South Africa, an estimated 2.5 million children have been orphaned by AIDS and other causes of adult mortality. Although there is a growing body of research on the well-being of South African orphaned children, few research studies have examined the health of adult individuals caring for children in HIV endemic communities. The cross-sectional survey assessed prevalence of general health and functioning (based on Short-Form 36 version 2 scale), depression (based on Center for Epidemiologic Studies-Depression scale), anxiety (using Kessler-10 scale), and post-traumatic stress (using the Harvard Trauma Questionnaire) among a representative community sample of adults caring for children in Umlazi Township, an HIV endemic community in South Africa. Of 1599 respondents, 33% (n=530) were carers of orphaned children. Results showed that, overall, carers reported poor general health and functioning, and elevated levels of depression, anxiety, and post-traumatic stress. Carers of orphaned children reported significantly poorer general health and functioning and higher rates of depression and post-traumatic stress compared to carers of non-orphaned children. In multivariate analyses, orphan carer and non-orphan carer differences in general health were accounted for by age, gender, education, economic assets, and source of income, but differences in depression were independent of these co-factors. Interventions are needed to address physical and mental health of carers in general. Greater health problems among orphan carers appeared to be fully explained by socioeconomic characteristics, which offer opportunities for targeting of programs. More research is needed to understand determinants of mental health disparities among orphan carers, which were not explained by socioeconomic characteristics. PMID:21480009

The Vulnerabilities of Orphaned Children Participating in Research: A Critical Review and Factors for Consideration for Participation in Biomedical and Behavioral Research

PubMed Central

Thompson, Rachel T.; Meslin, Eric M.; Braitstein, Paula K. A.; Nyandiko, Winstone M.; Ayaya, Samuel O.; Vreeman, Rachel C.

2013-01-01

Orphans are a subpopulation with a unique set of additional vulnerabilities. Increasing focus on children’s rights, pediatric global health, and pediatric research makes it imperative to recognize and address unique vulnerabilities of orphaned children. This paper describes the unique vulnerabilities of the orphaned pediatric population and offers a structured set of factors that require consideration when including orphans in biomedical research. Pediatric orphans are particularly vulnerable due to decreased economic resources, psychosocial instability, increased risk of abuse, and delayed/decreased access to healthcare. These vulnerabilities are significant. By carefully considering each issue in a population in a culturally specific and study-specific manner, researchers can make valuable contributions to the overall health and well-being of this uniquely vulnerable population. PMID:23086048

Neglect and perceived stigmatization impact psychological distress of orphans in Tanzania

PubMed Central

Hermenau, Katharin; Eggert, Ina; Landolt, Markus A.; Hecker, Tobias

2015-01-01

Background Research has shown that orphans in sub-Saharan Africa are at increased risk for mental health problems. Exposure to maltreatment and HIV/AIDS-related stigmatization are related to orphans’ psychological distress. Yet, researchers stress the need for more research in low-income countries to identify which factors of being an orphan may lead to psychological distress. Objectives The present study aims to systematically investigate orphans’ experiences of maltreatment and stigmatization to identify factors that relate to their psychological distress. Methods In total, 89 Tanzanian children who had lost at least one parent were compared to 89 matched non-orphans (mean age: 11 years; 51% boys). We measured exposure to maltreatment and perceived stigmatization as an orphan. Mental health was assessed using the Strengths and Difficulties Questionnaire, the Children's Depression Inventory, the UCLA PTSD Index for Children, and the Reactive–Proactive Questionnaire. Results Orphans reported significantly more experiences of neglect, but not of abuse. A group comparison revealed more depressive symptoms, posttraumatic stress symptoms, and aggressive behavior among orphans. Neglect, abuse, and stigmatization correlated with orphans’ internalizing and externalizing problems, yet only neglect and stigmatization were related to orphans’ depression severity. Perceived stigmatization moderated the relationship between neglect and depression. Conclusions Our findings suggest that orphans in Tanzania are at increased risk of experiencing neglect. Maltreatment and perceived stigmatization may play a role in orphans’ psychological distress. Culturally appropriate and evidence-based interventions may help to prevent maltreatment and stigmatization of orphans. PMID:26589257

What makes orphans in Kigali, Rwanda, non-adherent to antiretroviral therapy? Perspectives of their caregivers.

PubMed

Kikuchi, Kimiyo; Poudel, Krishna C; Muganda, John; Sato, Tomoko; Mutabazi, Vincent; Muhayimpundu, Ribakare; Majyambere, Adolphe; Nyonsenga, Simon P; Sase, Eriko; Jimba, Masamine

2014-01-01

Every year, approximately 260,000 children are infected with HIV in low- and middle-income countries. The timely initiation and high level of maintenance of antiretroviral therapy (ART) are crucial to reducing the suffering of HIV-positive children. We need to develop a better understanding of the background of children's ART non-adherence because it is not well understood. The purpose of this study is to explore the background related to ART non-adherence, specifically in relation to the orphan status of children in Kigali, Rwanda. We conducted 19 focus group discussions with a total of 121 caregivers of HIV-positive children in Kigali. The primary data for analysis were verbatim transcripts and socio-demographic data. A content analysis was performed for qualitative data analysis and interpretation. The study found several contextual factors that influenced non-adherence: among double orphans, there was psychological distance between the caregivers and children, whereas economic burden was the primary issue among paternal orphans. The factors promoting adherence also were unique to each orphan status, such as the positive attitude about disclosing serostatus to the child by double orphans' caregivers, and feelings of guilt about the child's condition among non-orphaned caregivers. Knowledge of orphan status is essential to elucidate the factors influencing ART adherence among HIV-positive children. In this qualitative study, we identified the orphan-related contextual factors that influenced ART adherence. Understanding the social context is important in dealing with the challenges to ART adherence among HIV-positive children.

Barriers and Incentives to Orphan Care in a Time of AIDS and Economic Crisis: A Cross-Sectional Survey of Caregivers in Rural Zimbabwe

ERIC Educational Resources Information Center

Howard, Brian H.; Phillips, Carl V.; Matinhure, Nelia; Goodman, Karen J.; McCurdy, Sheryl A; Johnson, Cary A.

2007-01-01

Background: Africa is in an orphan-care crisis. In Zimbabwe, where one-fourth of adults are HIV-positive and one-fifth of children are orphans, AIDS and economic decline are straining society's ability to care for orphans within their extended families. Lack of stable care is putting thousands of children at heightened risk of malnourishment,…

True Religion Cares for Orphans: Creating and Sustaining an Orphan Care Culture in the Local Churches in Rwanda a Phenomenological Study

ERIC Educational Resources Information Center

McMillan, Mary Ann

2017-01-01

This research, a phenomenological study, examined four different local churches in Rwanda to identify the key strategies and methods used to establish an orphan care culture and ministry. Saddleback Church in Lake Forest, California has partnered with the country of Rwanda to end the orphan crisis. As of today, 35 orphanages in the country of…

Stigma, marginalization and psychosocial well-being of orphans in Rwanda: exploring the mediation role of social support.

PubMed

Caserta, Tehetna Alemu; Pirttilä-Backman, Anna-Maija; Punamäki, Raija-Leena

2016-01-01

Stigma and marginalization are one of the major challenges orphans face in their daily lives, particularly in developing countries, but little is known about their impacts on mental health. This study examines how orphan-related characteristics, stigma and marginalization are associated with psychosocial well-being. It further analyses the role of social support in mediating between stigma and marginalization and mental health, indicated by emotional well-being and mental distress. The participants in this study were 430 Rwandan orphans who were 10-25 years of age, and of whom 179 were females and 251 were males. Results showed that high levels of stigma and marginalization were associated with a lower level of emotional well-being and higher levels of mental distress. A mediation analysis indicated that low level of social support due to stigma and marginalization contributed significantly to low level of emotional well-being. Once stigma, marginalization and social support were fully accounted for, AIDS orphans exhibited higher levels of mental distress than those who were orphaned by genocide or other causes. Future interventions designed to reduce stigma and marginalization for orphans and actions that facilitate social support can significantly improve emotional well-being and reduce mental distress among orphans.

Challenges to orphan drugs access in Eastern Europe: the case of Bulgaria.

PubMed

Iskrov, Georgi; Miteva-Katrandzhieva, Tsonka; Stefanov, Rumen

2012-11-01

This article explores how an Eastern European country could deal with orphan drugs access, combining EU policies with its own national settings. The cross-sectional observational study takes the total number of orphan drugs (61) available on EU level by March 2011, and then consecutively filters it through the requirements and criteria of relevant Bulgarian legislation on registration, pricing and reimbursement of medicinal products, obtaining the final number of accessible orphan drugs (16) in Bulgaria. The study further evaluates the average time period from market authorisation to positive reimbursement decision by Bulgarian health authorities (43±29.1 months). Access to orphan drugs should be provided on a reasonable and justified basis. Having in mind the limited availability of resources, it is not a question whether to prioritise rarity, but to create legitimate mechanisms for properly assessing orphan drugs' value and optimally using this value, according to the society's needs and views. The analysis identifies four important challenges to orphan drugs' access in Eastern Europe: (1) elaboration of new orphan drugs pricing approaches, (2) further interaction of cost-effectiveness analysis with medical criteria, (3) active introduction of epidemiological registries for rare diseases, and (4) research of societal preferences and raising public awareness. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

The evolving drug development landscape: from blockbusters to niche busters in the orphan drug space.

PubMed

Kumar Kakkar, Ashish; Dahiya, Neha

2014-06-01

Strategy, Management and Health Policy Large pharmaceutical companies have traditionally focused on the development of blockbuster drugs that target disease states with large patient populations. However, with large-scale patent expirations and competition from generics and biosimilars, anemic pipelines, escalating clinical trial costs, and global health-care reform, the blockbuster model has become less viable. Orphan drug initiatives and the incentives accompanied by these have fostered renewed research efforts in the area of rare diseases and have led to the approval of more than 400 orphan products. Despite targeting much smaller patient populations, the revenue-generating potential of orphan drugs has been shown to be huge, with a greater return on investment than non-orphan drugs. The success of these "niche buster" therapeutics has led to a renewed interest from "Big Pharma" in the rare disease landscape. This article reviews the key drivers for orphan drug research and development, their profitability, and issues surrounding the emergence of large pharmaceutical firms into the orphan drug space. © 2014 Wiley Periodicals, Inc.

Defect of Hepatocyte Growth Factor Activator Inhibitor Type 1/Serine Protease Inhibitor, Kunitz Type 1 (Hai-1/Spint1) Leads to Ichthyosis-Like Condition and Abnormal Hair Development in Mice

PubMed Central

Nagaike, Koki; Kawaguchi, Makiko; Takeda, Naoki; Fukushima, Tsuyoshi; Sawaguchi, Akira; Kohama, Kazuyo; Setoyama, Mitsuru; Kataoka, Hiroaki

2008-01-01

Hepatocyte growth factor activator inhibitor type 1 (HAI-1)/serine protease inhibitor, Kunitz type 1 (SPINT1) is a membrane-bound, serine proteinase inhibitor initially identified as an inhibitor of hepatocyte growth factor activator. It also inhibits matriptase and prostasin, both of which are membrane-bound serine proteinases that have critical roles in epidermal differentiation and function. In this study, skin and hair phenotypes of mice lacking the Hai-1/Spint1 gene were characterized. Previously, we reported that the homozygous deletion of Hai-1/Spint1 in mice resulted in embryonic lethality attributable to impaired placental development. To test the role of Hai-1/Spint1 in mice, the placental function of Hai-1/Spint1-mutant mice was rescued. Injection of Hai-1/Spint1+/+ blastocysts with Hai-1/Spint1−/− embryonic stem cells successfully generated high-chimeric Hai-1/Spint1−/− embryos (B6Hai-1−/−High) with normal placentas. These embryos were delivered without apparent developmental abnormalities, confirming that embryonic lethality of Hai-1/Spint1−/− mice was caused by placental dysfunction. However, newborn B6Hai-1−/−High mice showed growth retardation and died by 16 days. These mice developed scaly skin because of hyperkeratinization, reminiscent of ichthyosis, and abnormal hair shafts that showed loss of regular cuticular septation. The interfollicular epidermis showed acanthosis with enhanced Akt phosphorylation. Immunoblot analysis revealed altered proteolytic processing of profilaggrin in Hai-1/Spint1-deleted skin with impaired generation of filaggrin monomers. These findings indicate that Hai-1/Spint1 has critical roles in the regulated keratinization of the epidermis and hair development. PMID:18832587

Genetic variation of the VP1 gene of the virulent duck hepatitis A virus type 1 (DHAV-1) isolates in Shandong province of China.

PubMed

Gao, Jiming; Chen, Junhao; Si, Xingkui; Xie, Zhijing; Zhu, Yanli; Zhang, Xingxiao; Wang, Shujing; Jiang, Shijin

2012-08-01

To investigate the relationship of the variation of virulence and the external capsid proteins of the pandemic duck hepatitis A virus type 1 (DHAV-1) isolates, the virulence, cross neutralization assays and the complete sequence of the virion protein 1 (VP1) gene of nine virulent DHAV-1 strains, which were isolated from infected ducklings with clinical symptoms in Shandong province of China in 2007-2008, were tested. The fifth generation duck embryo allantoic liquids of the 9 isolates were tested on 12-day-old duck embryos and on 7-day-old ducklings for the median embryonal lethal doses (ELD(50)s) and the median lethal doses (LD(50)s), respectively. The results showed that the ELD(50)s of embryonic duck eggs of the 9 DHAV-1 isolates were between 1.9 × 10(6)/mL to 1.44 × 10(7)/mL, while the LD(50)s were 2.39 × 10(5)/mL to 6.15 × 10(6)/mL. Cross-neutralization tests revealed that the 9 DHAV-1 isolates were completely neutralized by the standard serum and the hyperimmune sera against the 9 DHAV-1 isolates, respectively. Compared with other virulent, moderate virulent, attenuated vaccine and mild strains, the VP1 genes of the 9 strains shared 89.8%-99.7% similarity at the nucleotide level and 92.4%-99.6% at amino acid level with other DHAV-1 strains. There were three hypervariable regions at the C-terminus (aa 158-160, 180-193 and 205-219) and other variable points in VP1 protein, but which didn't cause virulence of DHAV-1 change.

Lack of WDR36 leads to preimplantation embryonic lethality in mice and delays the formation of small subunit ribosomal RNA in human cells in vitro.

PubMed

Gallenberger, Martin; Meinel, Dominik M; Kroeber, Markus; Wegner, Michael; Milkereit, Philipp; Bösl, Michael R; Tamm, Ernst R

2011-02-01

Mutations in WD repeat domain 36 gene (WDR36) play a causative role in some forms of primary open-angle glaucoma, a leading cause of blindness worldwide. WDR36 is characterized by the presence of multiple WD40 repeats and shows homology to Utp21, an essential protein component of the yeast small subunit (SSU) processome required for maturation of 18S rRNA. To clarify the functional role of WDR36 in the mammalian organism, we generated and investigated mutant mice with a targeted deletion of Wdr36. In parallel experiments, we used RNA interference to deplete WDR36 mRNA in mouse embryos and cultured human trabecular meshwork (HTM-N) cells. Deletion of Wdr36 in the mouse caused preimplantation embryonic lethality, and essentially similar effects were observed when WDR36 mRNA was depleted in mouse embryos by RNA interference. Depletion of WDR36 mRNA in HTM-N cells caused apoptotic cell death and upregulation of mRNA for BAX, TP53 and CDKN1A. By immunocytochemistry, staining for WDR36 was observed in the nucleolus of cells, which co-localized with that of nucleolar proteins such as nucleophosmin and PWP2. In addition, recombinant and epitope-tagged WDR36 localized to the nucleolus of HTM-N cells. By northern blot analysis, a substantial decrease in 21S rRNA, the precursor of 18S rRNA, was observed following knockdown of WDR36. In addition, metabolic-labeling experiments consistently showed a delay of 18S rRNA maturation in WDR36-depleted cells. Our results provide evidence that WDR36 is an essential protein in mammalian cells which is involved in the nucleolar processing of SSU 18S rRNA.

Rapid DNA Synthesis During Early Drosophila Embryogenesis Is Sensitive to Maternal Humpty Dumpty Protein Function.

PubMed

Lesly, Shera; Bandura, Jennifer L; Calvi, Brian R

2017-11-01

Problems with DNA replication cause cancer and developmental malformations. It is not fully understood how DNA replication is coordinated with development and perturbed in disease. We had previously identified the Drosophila gene humpty dumpty ( hd ), and showed that null alleles cause incomplete DNA replication, tissue undergrowth, and lethality. Animals homozygous for the missense allele, hd 272-9 , were viable, but adult females had impaired amplification of eggshell protein genes in the ovary, resulting in the maternal effects of thin eggshells and embryonic lethality. Here, we show that expression of an hd transgene in somatic cells of the ovary rescues amplification and eggshell synthesis but not embryo viability. The germline of these mothers remain mutant for the hd 272-9 allele, resulting in reduced maternal Hd protein and embryonic arrest during mitosis of the first few S/M nuclear cleavage cycles with chromosome instability and chromosome bridges. Epistasis analysis of hd with the rereplication mutation plutonium indicates that the chromosome bridges of hd embryos are the result of a failed attempt to segregate incompletely replicated sister chromatids. This study reveals that maternally encoded Humpty dumpty protein is essential for DNA replication and genome integrity during the little-understood embryonic S/M cycles. Moreover, the two hd 272-9 maternal-effect phenotypes suggest that ovarian gene amplification and embryonic cleavage are two time periods in development that are particularly sensitive to mild deficits in DNA replication function. This last observation has broader relevance for interpreting why mild mutations in the human ortholog of humpty dumpty and other DNA replication genes cause tissue-specific malformations of microcephalic dwarfisms. Copyright © 2017 by the Genetics Society of America.

Impaired Embryonic Development in Mice Overexpressing the RNA-Binding Protein TIAR

PubMed Central

Kharraz, Yacine; Salmand, Pierre-Adrien; Camus, Anne; Auriol, Jacques; Gueydan, Cyril; Kruys, Véronique; Morello, Dominique

2010-01-01

Background TIA-1-related (TIAR) protein is a shuttling RNA-binding protein involved in several steps of RNA metabolism. While in the nucleus TIAR participates to alternative splicing events, in the cytoplasm TIAR acts as a translational repressor on specific transcripts such as those containing AU-Rich Elements (AREs). Due to its ability to assemble abortive pre-initiation complexes coalescing into cytoplasmic granules called stress granules, TIAR is also involved in the general translational arrest observed in cells exposed to environmental stress. However, the in vivo role of this protein has not been studied so far mainly due to severe embryonic lethality upon tiar invalidation. Methodology/Principal Findings To examine potential TIAR tissue-specificity in various cellular contexts, either embryonic or adult, we constructed a TIAR transgenic allele (loxPGFPloxPTIAR) allowing the conditional expression of TIAR protein upon Cre recombinase activity. Here, we report the role of TIAR during mouse embryogenesis. We observed that early TIAR overexpression led to low transgene transmission associated with embryonic lethality starting at early post-implantation stages. Interestingly, while pre-implantation steps evolved correctly in utero, in vitro cultured embryos were very sensitive to culture medium. Control and transgenic embryos developed equally well in the G2 medium, whereas culture in M16 medium led to the phosphorylation of eIF2α that accumulated in cytoplasmic granules precluding transgenic blastocyst hatching. Our results thus reveal a differential TIAR-mediated embryonic response following artificial or natural growth environment. Conclusions/Significance This study reports the importance of the tightly balanced expression of the RNA-binding protein TIAR for normal embryonic development, thereby emphasizing the role of post-transcriptional regulations in early embryonic programming. PMID:20596534

The Orphan Drug Act: Restoring the Mission to Rare Diseases.

PubMed

Daniel, Michael G; Pawlik, Timothy M; Fader, Amanda N; Esnaola, Nestor F; Makary, Martin A

2016-04-01

The Orphan Drug Act has fostered drug development for patients with rare cancers and other diseases; however, current data suggest that companies are gaming the system to use the law for mainstream drugs. We identify a pattern of pharmaceutical companies submitting drugs to the Food and Drug Administration (FDA) as orphan drugs but once approved, the drugs are used broadly off-label with the lucrative orphan drug protections and exclusivity benefits. Since the law was passed, the proportion of new FDA-approved drugs that were submitted as orphan drugs has increased with a peak last year of 41% of all FDA-approved drugs approved as orphan drugs. On the basis of the current data, we suggest that patients with rare cancers and other diseases may suffer due to dilution of the incentives and benefits. We propose reform to increase submission scrutiny, decrease benefits based on off-label use, and increase price transparency.

Orphan diseases: state of the drug discovery art.

PubMed

Volmar, Claude-Henry; Wahlestedt, Claes; Brothers, Shaun P

2017-06-01

Since 1983 more than 300 drugs have been developed and approved for orphan diseases. However, considering the development of novel diagnosis tools, the number of rare diseases vastly outpaces therapeutic discovery. Academic centers and nonprofit institutes are now at the forefront of rare disease R&D, partnering with pharmaceutical companies when academic researchers discover novel drugs or targets for specific diseases, thus reducing the failure risk and cost for pharmaceutical companies. Considerable progress has occurred in the art of orphan drug discovery, and a symbiotic relationship now exists between pharmaceutical industry, academia, and philanthropists that provides a useful framework for orphan disease therapeutic discovery. Here, the current state-of-the-art of drug discovery for orphan diseases is reviewed. Current technological approaches and challenges for drug discovery are considered, some of which can present somewhat unique challenges and opportunities in orphan diseases, including the potential for personalized medicine, gene therapy, and phenotypic screening.

Difference in Psychosocial Well-being Between Paternal and Maternal AIDS Orphans in Rural China

PubMed Central

Zhao, Qun; Li, Xiaoming; Fang, Xiaoyi; Zhao, Guoxiang; Zhao, Junfeng; Lin, Xiuyun; Stanton, Bonita

2009-01-01

This study compares psychosocial well-being between paternal and maternal orphans in rural China in a sample (N = 459) of children who had lost one parent to HIV and who were in family-based care. Measures included academic marks, education expectation, trusting relationships with current caregivers, self-reported health status, depression, loneliness, posttraumatic stress, and social support. No significant differences were found between maternal and paternal orphans, except that paternal orphans reported better trusting relationships with caregivers than maternal orphans. Children with a healthy surviving parent reported significantly better depression, loneliness, posttraumatic stress, and social support scores than children with a sick parent. Analyses revealed significance with regard to orphan status on academic marks and trusting relationships with caregivers while controlling for age, gender, surviving parent’s health status, and family SES. Findings underscore the importance of psychosocial support for children whose surviving parent is living with HIV or another illness. PMID:20133172

Orphan strontium-87 in abyssal peridotites: daddy was a granite.

PubMed

Snow, J E; Hart, S R; Dick, H J

1993-12-17

The (87)Sr/(86)Sr ratios in some bulk abyssal and alpine peridotites are too high to be binary mixtures of depleted mantle and seawater components. The apparent excess, or "orphan," (87)Sr appears to be separated from its radioactive parent. Such observations were widely held to be analytical artifacts. Study of several occurrences of orphan (87)Sr shows that the orphan component in abyssal peridotite is located in the alteration products of olivine and enstatite in the peridotite. The orphan (87)Sr is most likely introduced by infiltration of low-temperature (<200 degrees C) seawater bearing suspended detrital particulates. These particulates include grains of detrital clay that are partly derived from continental (that is, granitic) sources and thus are highly radiogenic. Orphan (87)Sr and other radiogenic isotopes may provide a tracer for low-temperature seawater penetrating into the oceanic crust.

Orphan Strontium-87 in Abyssal Peridotites: Daddy Was a Granite

NASA Astrophysics Data System (ADS)

Snow, Jonathan E.; Hart, Stanley R.; Dick, Henry J. B.

1993-12-01

The 87Sr/86Sr ratios in some bulk abyssal and alpine peridotites are too high to be binary mixtures of depleted mantle and seawater components. The apparent excess, or "orphan," 87Sr appears to be separated from its radioactive parent. Such observations were widely held to be analytical artifacts. Study of several occurrences of orphan 87Sr shows that the orphan component in abyssal peridotite is located in the alteration products of olivine and enstatite in the peridotite. The orphan 87Sr is most likely introduced by infiltration of low-temperature (<200^circC) seawater bearing suspended detrital particulates. These particulates include grains of detrital clay that are partly derived from continental (that is, granitic) sources and thus are highly radiogenic. Orphan 87Sr and other radiogenic isotopes may provide a tracer for low-temperature seawater penetrating into the oceanic crust.

Parental Bereavement in Young Children Living in South Africa and Malawi: Understanding Mental Health Resilience.

PubMed

Macedo, A; Sherr, L; Tomlinson, M; Skeen, S; Roberts, K J

2018-04-17

Parental loss is a major stressful event found to increase risk of mental health problems in childhood. Yet, some children show resilient adaptation in the face of adversity across time. This study explores predictors of mental health resilience among parentally bereaved children in South Africa and Malawi, and their cumulative effect. The study also explores whether predictors of resilience differed between orphaned and non-orphaned children. Consecutive attenders of community based organisations (children;4-13 years, and their caregivers) were interviewed at baseline and 15-18 month follow up (n=833). Interviews comprised of inventories on demographic information, family data, child mental health, bereavement experience and community characteristics. Mental health screens were used to operationalise resilience as the absence of symptoms of depression, suicidality, trauma, emotional and behavioural problems. Almost 60% of children experienced parental loss. One quarter of orphaned children showed no mental health problems at either wave and were classified as resilient. There were equal proportions of children classified as resilient within the orphaned (25%) vs. non-orphaned group (22%). Being a quick learner, aiding ill family members, positive caregiving, household employment, higher community support, and lower exposure to domestic violence, physical punishment, or stigma at baseline predicted sustained resilience. There were cumulative influences of resilience predictors among orphaned children. Predictors of resilience did not vary by child age, gender, country of residence or between orphaned and non-orphaned children. This study enhances understanding of resilience in younger children and identifies a number of potential environmental and psychosocial factors for bolstering resilience in orphaned children.

Characterizing a Hidden Group of At-Risk Drinkers: Epidemiological Profiles of Alcohol-Use Disorder Diagnostic Orphans.

PubMed

Gilbert, Paul A; Marzell, Miesha

2017-11-29

Drinkers who report some symptoms of alcohol-use disorder (AUD) but fail to meet full criteria are "diagnostic orphans." To improve risk-reduction efforts, we sought to develop better epidemiologic profiles of this underrecognized subgroup. This study estimated the population prevalence and described AUD symptoms of diagnostic orphans using the 2012-2013 National Epidemiological Survey of Alcohol and Related Conditions-III. Multivariate logistic regression was used to model odds of being a diagnostic orphan or meeting mild, moderate, and severe AUD criteria versus no AUD symptoms. Models were adjusted for the complex survey design using sampling weights and survey procedures (e.g., proc surveylogistic). Among drinkers, 14% of men and 11% of women were classified as diagnostic orphans. The most common symptoms were drinking more or for longer periods than intended, wanting or trying unsuccessfully to quit or cut back, and drinking in ways that increased risk of injury. We noted broad similarities between diagnostic orphans and mild/moderate AUD groups. There were no differences in odds of diagnostic orphans status by race/ethnicity; however, female gender was associated with lower odds of diagnostic orphan status and all levels of AUD. Individual history of AUD, family history of problem drinking, concurrent smoking, and concurrent marijuana use were associated with greater odds of problem drinking, with stronger associations as AUD severity increased. Diagnostic orphans remain a sizeable and overlooked population of problem drinkers. Clarifying the array of symptoms and cooccurring disorders can improve screening and facilitate alcohol risk-reduction intervention efforts.

Reimbursement of orphan drugs in Belgium: what (else) matters?

PubMed

Picavet, Eline; Cassiman, David; Simoens, Steven

2014-09-12

Most orphan drugs do not meet traditional standards of cost-effectiveness. Yet, most orphan drugs are reimbursed, which implies that other factors are taken into account at the time of reimbursement. To increase accountability of decision-makers, there is a need for more transparency in the factors that play a role in reimbursement decisions of orphan drugs. Therefore, the aim of this study is to use a combination of qualitative research methods to examine which official and non-official factors influence reimbursement decisions for orphan drugs in Belgium. Six semi-structured interviews with past or present members of the Drug Reimbursement Committee (DRC) were performed with a view to obtaining an overview of the potential factors influencing reimbursement. Additionally, these presence of these factors was assessed in the reimbursement dossiers of all orphan drugs (n = 64) for which an application for reimbursement was submitted to the National Institute for Health and Disability Insurance in Belgium between January 2002 and July 2013. Different official (i.e. therapeutic value, budget impact, price and impact in clinical practice) and non-official factors (i.e. pricing and reimbursement in other countries, interference by patient organisations and experts, arguments related to quality of branded drug versus compounding, media attention, innovative character, economic importance, ethical arguments and the political climate) may have influenced past reimbursement decisions for orphan drugs in Belgium. The identification of factors influencing orphan drug reimbursement is a crucial step in the development of a transparent and consistent framework which will guide future decision-making for reimbursement of orphan drugs.

A deficiency of the homeotic complex of the beetle Tribolium

NASA Technical Reports Server (NTRS)

Stuart, J. J.; Brown, S. J.; Beeman, R. W.; Denell, R. E.; Spooner, B. S. (Principal Investigator)

1991-01-01

In Drosophila, the establishment of regional commitments along most of the anterior/posterior axis of the developing embryo depends on two clusters of homeotic genes: the Antennapedia complex (ANT-C) and the bithorax complex (BX-C). The red flour beetle has a single complex (HOM-C) representing the homologues of the ANT-C and BX-C in juxtaposition. Beetles trans-heterozygous for two particular HOM-C mutations spontaneously generate a large deficiency, presumably by an exchange within the common region of two overlapping inversions. Genetic and molecular results indicate that this deficiency spans at least the interval between the Deformed and abdominal-A homologues. In deficiency homozygous embryos, all gnathal, thoracic and abdominal segments develop antennal appendages, suggesting that a gene(s) has been deleted that acts to distinguish trunk from head. There is no evidence that beetles have a homologue of the segmentation gene fushi tarazu of similar genomic location and function. On the basis of the genetic tractability, convenient genome size and organization of Tribolium, and its relatively long phylogenetic divergence from Drosophila (>300 million years), we have integrated developmental genetic and molecular analyses of the HOM-C. We isolated about 70 mutations in the complex representing at least six complementation groups. The homeotic phenotypes of adults and lethal embryos lead us to believe that these beetle genes are homologous with the Drosophila genes indicated in Fig. 1 (see text).

Comparative analysis of water quality and toxicity assessment methods for urban highway runoff.

PubMed

Chen, Rui-Hong; Li, Fei-Peng; Zhang, Hai-Ping; Jiang, Yue; Mao, Ling-Chen; Wu, Ling-Ling; Chen, Ling

2016-05-15

In this study, comparative analyses of highway runoff samples obtained from seventeen storm events have been conducted between the traditional water quality assessment method and biotoxicity tests, using zebrafish (Danio rerio) embryos and luminous bacteria (Vibrio qinghaiensis. Q67) to provide useful information for ecotoxicity assessment of urban highway runoff. The study results showed that the Nemerow pollution index based on US EPA recommended Criteria Maximum Concentrations (CMC) (as traditional water quality assessment method) had no significant correlation with luminous bacteria acute toxicity test results, while significant correlation has been observed with two indicators of 72 hpf (hours post fertilization) hour hatching rate and 96 hpf abnormality rate from the toxicity test with zebrafish embryos. It is therefore concluded that the level of mixture toxicity of highway runoff could not be adequately measured by the Nemerow assessment method. Moreover, the key pollutants identified from the water quality assessment and from the biotoxicity evaluation were not consistent. For biotoxic effect evaluation of highway runoff, three indexes were found to be sensitive, i.e. 24 hpf lethality and 96 hpf abnormality of zebrafish embryos, as well as the inhibition rate for luminous bacteria Q67. It is therefore recommended that these indexes could be incorporated into the traditional Nemerow method to provide a more reasonable evaluation of the highway runoff quality and ecotoxicity. Copyright © 2016 Elsevier B.V. All rights reserved.

DarT: The embryo test with the Zebrafish Danio rerio--a general model in ecotoxicology and toxicology.

PubMed

Nagel, Roland

2002-01-01

The acute fish test is an animal test whose ecotoxicological relevance is worthy of discussion. The primary aim of protection in ecotoxicology is the population and not the individual. Furthermore the concentration of pollutants in the environment is normally not in the lethal range. Therefore the acute fish test covers solely the situation after chemical spills. Nevertheless, acute fish toxicity data still belong to the base set used for the assessment of chemicals. The embryo test with the zebrafish Danio rerio (DarT) is recommended as a substitute for the acute fish test. For validation an international laboratory comparison test was carried out. A summary of the results is presented in this paper. Based on the promising results of testing chemicals and waste water the test design was validated by the DIN-working group "7.6 Fischei-Test". A normed test guideline for testing waste water with fish is available. The test duration is short (48 h) and within the test different toxicological endpoints can be examined. Endpoints from the embryo test are suitable for QSAR-studies. Besides the use in ecotoxicology the introduction as a toxicological model was investigated. Disturbance of pigmentation and effects on the frequency of heart-beat were examined. A further important application is testing of teratogenic chemicals. Based on the results DarT could be a screening test within preclinical studies.

Effects of Nanosilver Exposure on Cholinesterase Activities, CD41, and CDF/LIF-Like Expression in ZebraFish (Danio rerio) Larvae

PubMed Central

Myrzakhanova, Marzhan; Gambardella, Chiara; Falugi, Carla; Gatti, Antonietta M.; Tagliafierro, Grazia; Diaspro, Alberto

2013-01-01

Metal nanosolicoparticles are suspected to cause diseases in a number of organisms, including man. In this paper, we report the effects of nanosilver (Ag, 1–20 nm particles) on the early development of the zebrafish, a well-established vertebrate model. Embryos at the midgastrula stage were exposed to concentrations ranging from 100 to 0.001 mg/L to verify the effects on different endpoints: lethality, morphology, expression of cholinergic molecules, and development of the immune system. (1) Relative risk of mortality was exponential in the range between 0.001 and 10 mg/L. Exposure to 100 mg/L caused 100% death of embryos before reaching the tail-bud stage. (2) Developmental anomalies were present in the 72 h larvae obtained from embryos exposed to nanosilver: whole body length, decreased eye dimension, and slow response to solicitation by gentle touch with a needle tip, with a significant threshold at 0.1 mg/L. (3) Dose-dependent inhibition of acetylcholinesterase activity was significant among the exposures, except between 1 mg/L and 10 mg/L. (4) The distribution of CD41+ cells and of CDF/LIF-like immunoreactivity was altered according to the Ag concentration. The possible effect of nanosilver in impairing immune system differentiation through the inhibition of molecules related to the cholinergic system is discussed. PMID:23991412

A deficiency of the homeotic complex of the beetle Tribolium.

PubMed

Stuart, J J; Brown, S J; Beeman, R W; Denell, R E

1991-03-07

In Drosophila, the establishment of regional commitments along most of the anterior/posterior axis of the developing embryo depends on two clusters of homeotic genes: the Antennapedia complex (ANT-C) and the bithorax complex (BX-C). The red flour beetle has a single complex (HOM-C) representing the homologues of the ANT-C and BX-C in juxtaposition. Beetles trans-heterozygous for two particular HOM-C mutations spontaneously generate a large deficiency, presumably by an exchange within the common region of two overlapping inversions. Genetic and molecular results indicate that this deficiency spans at least the interval between the Deformed and abdominal-A homologues. In deficiency homozygous embryos, all gnathal, thoracic and abdominal segments develop antennal appendages, suggesting that a gene(s) has been deleted that acts to distinguish trunk from head. There is no evidence that beetles have a homologue of the segmentation gene fushi tarazu of similar genomic location and function. On the basis of the genetic tractability, convenient genome size and organization of Tribolium, and its relatively long phylogenetic divergence from Drosophila (>300 million years), we have integrated developmental genetic and molecular analyses of the HOM-C. We isolated about 70 mutations in the complex representing at least six complementation groups. The homeotic phenotypes of adults and lethal embryos lead us to believe that these beetle genes are homologous with the Drosophila genes indicated in Fig. 1 (see text).

The role of the proline-rich domain of Ssdp1 in the modular architecture of the vertebrate head organizer

PubMed Central

Enkhmandakh, Badam; Makeyev, Alexandr V.; Bayarsaihan, Dashzeveg

2006-01-01

Lim1, Ssdp1, and Ldb1 proteins are components of the Ldb1-associated transcriptional complex, which is important in the head-organizing activity during early mouse development. Depletion of each individual protein alone causes a headless phenotype. To explore in more detail the modular architecture of the complex, we have generated two different gene-trapped mouse lines that express truncated forms of Ssdp1. Embryos derived from the gene-trapped line that encodes a truncated Ssdp1 lacking the proline-rich sequence exhibit a lethal abnormal head-development phenotype, resembling mouse embryos deficient for Lim1, Ssdp1, or Otx2 genes. Embryos derived from the second gene-trapped line, in which most of the proline-rich domain of Ssdp1 is retained, did not show abnormalities in head development. Our data demonstrate that components of the Ldb1-dependent module can be subdivided further into discrete functional domains and that the proline-rich stretch of Ssdp1 is critical for embryonic head development. Furthermore, phylogenetic comparisons revealed that in Caenorhabditis elegans, a similar proline-rich sequence is absent in Ssdp but present in Ldb1. We conclude that although the overall architecture of the Ldb1-dependent module has been preserved, the genetic specification of its individual components has diversified during evolution, without compromising the function of the module. PMID:16864769

The role of the proline-rich domain of Ssdp1 in the modular architecture of the vertebrate head organizer.

PubMed

Enkhmandakh, Badam; Makeyev, Alexandr V; Bayarsaihan, Dashzeveg

2006-08-01

Lim1, Ssdp1, and Ldb1 proteins are components of the Ldb1-associated transcriptional complex, which is important in the head-organizing activity during early mouse development. Depletion of each individual protein alone causes a headless phenotype. To explore in more detail the modular architecture of the complex, we have generated two different gene-trapped mouse lines that express truncated forms of Ssdp1. Embryos derived from the gene-trapped line that encodes a truncated Ssdp1 lacking the proline-rich sequence exhibit a lethal abnormal head-development phenotype, resembling mouse embryos deficient for Lim1, Ssdp1, or Otx2 genes. Embryos derived from the second gene-trapped line, in which most of the proline-rich domain of Ssdp1 is retained, did not show abnormalities in head development. Our data demonstrate that components of the Ldb1-dependent module can be subdivided further into discrete functional domains and that the proline-rich stretch of Ssdp1 is critical for embryonic head development. Furthermore, phylogenetic comparisons revealed that in Caenorhabditis elegans, a similar proline-rich sequence is absent in Ssdp but present in Ldb1. We conclude that although the overall architecture of the Ldb1-dependent module has been preserved, the genetic specification of its individual components has diversified during evolution, without compromising the function of the module.

Comparative Analysis of Metallic Nanoparticles as Exogenous Soft Tissue Contrast for Live In Vivo Micro-Computed Tomography Imaging of Avian Embryonic Morphogenesis

PubMed Central

Gregg, Chelsea L.; Butcher, Jonathan T.

2016-01-01

Background Gestationally survivable congenital malformations arise during mid-late stages of development that are inaccessible in vivo with traditional optical imaging for assessing long term abnormal patterning. MicroCT is an attractive technology to rapidly and inexpensively generate quantitative 3D datasets but requires exogenous contrast media. Here we establish dose dependent toxicity, persistence, and biodistribution of three different metallic nanoparticles in day 4 chick embryos. Results We determined that 110nm alkaline earth metal particles were non-toxic and persisted in the chick embryo for up to 24 hours post injection with contrast enhancement levels at high as 1600HU. 15nm gold nanoparticles persisted with x-ray attenuation higher than that of the surrounding yolk and albumen for up to 8 hours post injection, while 1.9nm particles resulted in lethality by 8 hours. We identified spatial and temporally heterogeneous contrast enhancement ranging from 250-1600HU. With the most optimal 110nm alkaline earth metal particles, we quantified an exponential increase in the tissue perfusion versus distance from the dorsal aorta into the flank over 8 hours with a peak perfusion rate of 0.7um2/s measured at a distance of 0.3mm. Conclusion These results demonstrate the safety, efficacy, and opportunity of nanoparticle based contrast media in live embryos for quantitative analysis of embryogenesis. PMID:27447729

BALB/c alleles at modifier loci increase the severity of the maternal effect of the "DDK syndrome".

PubMed Central

Le Bras, S; Cohen-Tannoudji, M; Kress, C; Vandormael-Pournin, S; Babinet, C; Baldacci, P

2000-01-01

The Om locus was first described in the DDK inbred mouse strain: DDK mice carry a mutation at Om resulting in a parental effect lethality of F(1) embryos. When DDK females are mated with males of other (non-DDK) inbred strains, e.g., BALB/c, they exhibit a low fertility, whereas the reciprocal cross, non-DDK females x DDK males, is fertile (as is the DDK intrastrain cross). The low fertility is due to the death of (DDK x non-DDK)F(1) embryos at the late-morula to blastocyst stage, which is referred to as the "DDK syndrome." The death of these F(1) embryos is caused by an incompatibility between a DDK maternal factor and the non-DDK paternal pronucleus. Previous genetic studies showed that F(1) mice have an intermediate phenotype compared to parental strains: crosses between F(1) females and non-DDK males are semisterile, as are crosses between DDK females and F(1) males. In the present studies, we have examined the properties of mice heterozygous for BALB/c and DDK Om alleles on an essentially BALB/c genetic background. Surprisingly, we found that the females are quasi-sterile when mated with BALB/c males and, thus, present a phenotype similar to DDK females. These results indicate that BALB/c alleles at modifier loci increase the severity of the DDK syndrome. PMID:10655231

Assessment of diclofenac LC50 reference values in juvenile and embryonic stages of the zebrafish (Danio rerio).

PubMed

Praskova, E; Voslarova, E; Siroka, Z; Plhalova, L; Macova, S; Marsalek, P; Pistekova, V; Svobodova, Z

2011-01-01

The aim of the study was to compare the acute toxicity of diclofenac to juvenile and embryonic stages of the zebrafish (Danio rerio). Acute toxicity tests were performed on the aquarium fish Danio rerio, which is one of the model organisms most commonly used in toxicity testing. The tests were performed using a semi-static method according to OECD guideline No. 203 (Fish, acute toxicity test). Embryo toxicity tests were performed in zebrafish embryos (Danio rerio) in compliance with OECD No. 212 methodology (Fish, short-term toxicity test on embryo and sac-fry stages). The results were subjected to a probit analysis using the EKO-TOX 5.2 programme to determine 96hLC50 and 144hLC50 (median lethal concentration, 50% mortality after a 96 h or 144 h interval, respectively) values of diclofenac. The statistical significance of the difference between LC50 values in juvenile and embryonic stages of Danio rerio was tested using the Mann-Whitney non-parametric test implemented in the Unistat 5.1 programme. The LC50 mean value of diclofenac was 166.6 +/- 9.8 mg/L in juvenile Danio rerio, and 6.11 +/- 2.48 mg/L in embryonic stages of Danio rerio. The study demonstrated a statistically higher sensitivity to diclofenac (P < 0.05) in embryonic stages compared to the juvenile fish.

Effects of cash transfers on Children's health and social protection in Sub-Saharan Africa: differences in outcomes based on orphan status and household assets.

PubMed

Crea, Thomas M; Reynolds, Andrew D; Sinha, Aakanksha; Eaton, Jeffrey W; Robertson, Laura A; Mushati, Phyllis; Dumba, Lovemore; Mavise, Gideon; Makoni, J C; Schumacher, Christina M; Nyamukapa, Constance A; Gregson, Simon

2015-05-28

Unconditional and conditional cash transfer programmes (UCT and CCT) show potential to improve the well-being of orphans and other children made vulnerable by HIV/AIDS (OVC). We address the gap in current understanding about the extent to which household-based cash transfers differentially impact individual children's outcomes, according to risk or protective factors such as orphan status and household assets. Data were obtained from a cluster-randomised controlled trial in eastern Zimbabwe, with random assignment to three study arms - UCT, CCT or control. The sample included 5,331 children ages 6-17 from 1,697 households. Generalized linear mixed models were specified to predict OVC health vulnerability (child chronic illness and disability) and social protection (birth registration and 90% school attendance). Models included child-level risk factors (age, orphan status); household risk factors (adults with chronic illnesses and disabilities, greater household size); and household protective factors (including asset-holding). Interactions were systematically tested. Orphan status was associated with decreased likelihood for birth registration, and paternal orphans and children for whom both parents' survival status was unknown were less likely to attend school. In the UCT arm, paternal orphans fared better in likelihood of birth registration compared with non-paternal orphans. Effects of study arms on outcomes were not moderated by any other risk or protective factors. High household asset-holding was associated with decreased likelihood of child's chronic illness and increased birth registration and school attendance, but household assets did not moderate the effects of cash transfers on risk or protective factors. Orphaned children are at higher risk for poor social protection outcomes even when cared for in family-based settings. UCT and CCT each produced direct effects on children's social protection which are not moderated by other child- and household-level risk factors, but orphans are less likely to attend school or obtain birth registration. The effects of UCT and CCT are not moderated by asset-holding, but greater household assets predict greater social protection outcomes. Intervention efforts need to focus on ameliorating the additional risk burden carried by orphaned children. These efforts might include caregiver education, and additional incentives based on efforts made specifically for orphaned children.

ASF1 is required to load histones on the HIRA complex in preparation of paternal chromatin assembly at fertilization.

PubMed

Horard, Béatrice; Sapey-Triomphe, Laure; Bonnefoy, Emilie; Loppin, Benjamin

2018-05-11

Anti-Silencing Factor 1 (ASF1) is a conserved H3-H4 histone chaperone involved in both Replication-Coupled and Replication-Independent (RI) nucleosome assembly pathways. At DNA replication forks, ASF1 plays an important role in regulating the supply of H3.1/2 and H4 to the CAF-1 chromatin assembly complex. ASF1 also provides H3.3-H4 dimers to HIRA and DAXX chaperones for RI nucleosome assembly. The early Drosophila embryo is an attractive system to study chromatin assembly in a developmental context. The formation of a diploid zygote begins with the unique, genome-wide RI assembly of paternal chromatin following sperm protamine eviction. Then, within the same cytoplasm, syncytial embryonic nuclei undergo a series of rapid, synchronous S and M phases to form the blastoderm embryo. Here, we have investigated the implication of ASF1 in these two distinct assembly processes. We show that depletion of the maternal pool of ASF1 with a specific shRNA induces a fully penetrant, maternal effect embryo lethal phenotype. Unexpectedly, despite the depletion of ASF1 protein to undetectable levels, we show that asf1 knocked-down (KD) embryos can develop to various stages, thus demonstrating that ASF1 is not absolutely required for the amplification of cleavage nuclei. Remarkably, we found that ASF1 is required for the formation of the male pronucleus, although ASF1 protein does not reside in the decondensing sperm nucleus. In asf1 KD embryos, HIRA localizes to the male nucleus but is only capable of limited and insufficient chromatin assembly. Finally, we show that the conserved HIRA B domain, which is involved in ASF1-HIRA interaction, is dispensable for female fertility. We conclude that ASF1 is critically required to load H3.3-H4 dimers on the HIRA complex prior to histone deposition on paternal DNA. This separation of tasks could optimize the rapid assembly of paternal chromatin within the gigantic volume of the egg cell. In contrast, ASF1 is surprisingly dispensable for the amplification of cleavage nuclei, although chromatin integrity is likely compromised in KD embryos.

The oxidized state of the nanocomposite Carbo-Iron® causes no adverse effects on growth, survival and differential gene expression in zebrafish.

PubMed

Weil, Mirco; Meißner, Tobias; Busch, Wibke; Springer, Armin; Kühnel, Dana; Schulz, Ralf; Duis, Karen

2015-10-15

For degradation of halogenated chemicals in groundwater Carbo-Iron®, a composite of activated carbon and nano-sized Fe(0), was developed (Mackenzie et al., 2012). Potential effects of this nanocomposite on fish were assessed. Beyond the contaminated zone Fe(0) can be expected to have oxidized and Carbo-Iron was used in its oxidized form in ecotoxicological tests. Potential effects of Carbo Iron in zebrafish (Danio rerio) were investigated using a 48 h embryo toxicity test under static conditions, a 96 h acute test with adult fish under semi-static conditions and a 34 d fish early life stage test (FELST) in a flow-through system. Particle diameters in test suspensions were determined via dynamic light scattering (DLS) and ranged from 266 to 497 nm. Particle concentrations were measured weekly in samples from the FELST using a method based on the count rate in DLS. Additionally, uptake of particles into test organisms was investigated using microscopic methods. Furthermore, effects of Carbo-Iron on gene expression were investigated by microarray analysis in zebrafish embryos. In all tests performed, no significant lethal effects were observed. Furthermore, Carbo-Iron had no significant influence on weight and length of fish as determined in the FELST. In the embryo test and the early life stage test, growth of fungi on the chorion was observed at Carbo-Iron concentrations between 6.3 and 25mg/L. Fungal growth did not affect survival, hatching success and growth. In the embryo test, no passage of Carbo-Iron particles into the perivitelline space or the embryo was observed. In juvenile and adult fish, Carbo-Iron was detected in the gut at the end of exposure. In juvenile fish exposed to Carbo-Iron for 29 d and subsequently kept for 5d in control water, Carbo-Iron was no longer detectable in the gut. Global gene expression in zebrafish embryos was not significantly influenced by Carbo-Iron. Copyright © 2015 Elsevier B.V. All rights reserved.

Induction of metallothionein in chick embryos as a mechanism of tolerance to platinum group metal exposure.

PubMed

Gagnon, Zofia E; Patel, Amit

2007-02-15

Recent data show that platinum group metals (PGMs), primarily platinum (Pt), palladium (Pd) and rhodium (Rd), from automobile catalytic converters are being deposited in the environment. We investigated the PGM neurotoxicity and tolerance mechanism by induction of metallothionein (MT) in developing chick embryos. Chick embryos were injected on the 7th and 14th days of incubation with different concentrations of Pt and mixture of Pt, Pd and Rh (PGM mix) solutions. It is documented that induction of MT by zinc (Zn+2) protects against metal and non-metal hepatotoxicity. In this study the MT induction was examined through pretreatment of the two highest Pt(IV) exposure levels with exogenous Zn2+ on the 4th and 11th days of incubation. SDS-PAGE assay and digital image system were used to identify and quantify MT in homogenized brain and liver tissues. Quantitative analysis revealed an increase of MT in the 5 ppm Pt exposure as compared to controls. The 10 ppm Pt treatment was a lethal dose for exposed embryos. There was increased mortality at the 1.0 PGM mix level. The interaction of Pt, Pd and Rh in the mixture seems to favor metal accumulation and MT induction in the liver but not the brain. Pretreatment with exogenous Zn2+ increased chick survival. These results indicate that induction of MT plays a protective role against PGM toxicity. Metal analysis using atomic absorption spectrometer in graphite furnace mode (GFAAS) revealed PGM accumulation in chick embryo liver and brain tissues proportional to exposure concentration. Our results may imply that MT has an important role as a tolerance mechanism against PGM toxicity. The presence of Pt(IV) in brain tissue suggests that the undeveloped blood-brain barrier is permeable to PGMs. This raises concerns regarding the implication of these metals on neural injury.

Quantitative analysis to guide orphan drug development.

PubMed

Lesko, L J

2012-08-01

The development of orphan drugs for rare diseases has made impressive strides in the past 10 years. There has been a surge in orphan drug designations, but new drug approvals have not kept up. This article presents a three-pronged hierarchical strategy for quantitative analysis of data at the descriptive, mechanistic, and systems levels of the biological system that could represent a standardized and rational approach to orphan drug development. Examples are provided to illustrate the concept.

Parental HIV/AIDS and psychological health of younger children in South Africa.

PubMed

Asanbe, Comfort; Moleko, Anne-Gloria; Visser, Maretha; Thomas, Angela; Makwakwa, Catherine; Salgado, Waleska; Tesnakis, Alexandra

2016-07-01

We examined several indicators of psychological health in a sample of orphans and vulnerable children (OVC) to determine if there were significant differences between those orphaned by AIDS and those orphaned by other causes, and if there were gender differences. Our sample consisted of 119 young children (ages 6-10 years) who participated in a non-governmental organisation (NGO)-supported social services programme in a low-resource, non-urban community in South Africa. We collected data on three groups: non-orphans (OVC1; n = 45); orphans due to AIDS (OVC2; n = 43); and other orphans (OVC3; n = 31). Parents of non-orphans and legal guardians of orphans rated their children on a 112-item, age appropriate Child Behaviour Checklist (CBCL), South Africa version. Children in the OVC2 group were significantly different from their peers on Internalising Problems and Somatic Complaints, while OVC3 group had a higher proportion of children in the at-risk range on Social Problems compared to OVC2. Females had elevated scores on the anxious/depressed, internalising problems, total problems, and sluggish cognitive tempo scales compared to males. There was an interaction between factors, such that boys in OVC2 had elevated mean scores on Somatic Complaints. These findings suggest increased vulnerability for girls on emotional issues and for boys on somatic problems.

Caregiver alcohol use and mental health among children orphaned by HIV/AIDS in South Africa.

PubMed

Jardin, Charles; Marais, Lochner; Bakhshaie, Jafar; Skinner, Donald; Neighbors, Clayton; Zvolensky, Michael; Sharp, Carla

2017-03-01

Research in the developed world suggests that parental alcohol use negatively impacts child mental health. However, little research has examined these relations among children in the developing world and no studies to date have done so in the context of AIDS-orphanhood. Therefore, the present study tested the interactive effect of AIDS-orphan status with caregiver alcohol use on child mental health. The sample included 742 children (51.2% female; M age   = 9.18; age range: 7-11 years; 29.8 AIDS-orphans; 36.8% orphaned by causes other than AIDS; 33.4% non-orphaned) recruited from Mangaung in the Free State Province of South Africa. Child mental health was assessed via child self-report, caregiver, and teacher reports; and caregiver alcohol use via self-report. Path analyses, via structural equation modeling, revealed significant direct effects for AIDS-orphan status on caregiver-reported child mental health; and for caregiver alcohol-use problems on teacher-reported child mental health. However, the interaction effect of AIDS-orphan status with caregiver alcohol use did not reach significance on all three reports of child mental health problems. These results suggest that orphan status and caregiver alcohol use may independently relate to mental health problems in children and that the effects of both should be considered in the context of the mental health needs of children in AIDS-affected countries.

Lipid-sensors, enigmatic-orphan and orphan nuclear receptors as therapeutic targets in breast-cancer.

PubMed

Garattini, Enrico; Bolis, Marco; Gianni', Maurizio; Paroni, Gabriela; Fratelli, Maddalena; Terao, Mineko

2016-07-05

Breast-cancer is heterogeneous and consists of various groups with different biological characteristics. Innovative pharmacological approaches accounting for this heterogeneity are needed. The forty eight human Nuclear-Hormone-Receptors are ligand-dependent transcription-factors and are classified into Endocrine-Receptors, Adopted-Orphan-Receptors (Lipid-sensors and Enigmatic-Orphans) and Orphan-receptors. Nuclear-Receptors represent ideal targets for the design/synthesis of pharmacological ligands. We provide an overview of the literature available on the expression and potential role played by Lipid-sensors, Enigmatic-Orphans and Orphan-Receptors in breast-cancer. The data are complemented by an analysis of the expression levels of each selected Nuclear-Receptor in the PAM50 breast-cancer groups, following re-elaboration of the data publicly available. The major aim is to support the idea that some of the Nuclear-Receptors represent largely unexploited therapeutic-targets in breast-cancer treatment/chemo-prevention. On the basis of our analysis, we conclude that the Lipid-Sensors, NR1C3, NR1H2 and NR1H3 are likely to be onco-suppressors in breast-cancer. The Enigmatic-Orphans, NR1F1 NR2A1 and NR3B3 as well as the Orphan-Receptors, NR0B1, NR0B2, NR1D1, NR2F1, NR2F2 and NR4A3 exert a similar action. These Nuclear-Receptors represent candidates for the development of therapeutic strategies aimed at increasing their expression or activating them in tumor cells. The group of Nuclear-Receptors endowed with potential oncogenic properties consists of the Lipid-Sensors, NR1C2 and NR1I2, the Enigmatic-Orphans, NR1F3, NR3B1 and NR5A2, as well as the Orphan-Receptors, NR2E1, NR2E3 and NR6A1. These oncogenic Nuclear-Receptors should be targeted with selective antagonists, reverse-agonists or agents/strategies capable of reducing their expression in breast-cancer cells.

The impact of the declining extended family support system on the education of orphans in Lesotho

PubMed Central

Tanga, Pius T

2013-01-01

This paper examines the impact of the weakening of the extended family on the education of double orphans in Lesotho through in-depth interviews with participants from 3 of the 10 districts in Lesotho. The findings reveal that in Lesotho the extended family has not yet disintegrated as the literature suggests. However, it shows signs of rupturing, as many orphans reported that they are being taken into extended family households, the incentive for these households being, presumably, the financial and other material assistance that they receive from the government and non-governmental organisations (NGOs) which supplements household income and material wellbeing. The findings show that financial and other assistance given by the government and NGOs have resulted in conflict between the orphans and caregivers. This has also prompted many extended families to shift responsibilities to the government and NGOs. Most of the extended households provided the orphans with poor living conditions, such as unhygienic houses, poor nutrition, and little or no provision of school materials, which has had a negative impact on the education of the orphans. The combined effects of economic crisis and HIV and AIDS have resulted in extended families not being able to care for the needs of the orphans adequately, whilst continuing to accept them into their households. It is recommended that although extended families are still accepting orphans, the government should strengthen and recognise the important role played by families and the communities in caring for these vulnerable children. The government should also introduce social grants for orphans and other vulnerable children and review the current meagre public assistance (R100) it provides for orphans and vulnerable children in Lesotho. Other stakeholders should concentrate on strengthening the capacity of families and communities through programmes and projects which could be more sustainable than the current handouts given by many NGOs. PMID:24587791

[The Euro-orphans phenomenon and the courses in therapeutic work and psychiatric treatment--a case study].

PubMed

Nowak, Marta; Gaweda, Agnieszka; Janas-Kozik, Małgorzata

2012-01-01

Today, the phenomenon of Euro-orphan is more and more frequently reported in the literature. This term refers to children with one or both parents emigrated from the country for work purposes. In connection with the social transformations of orphan-hood types described in the literature (nature, spiritual, social), the definition has been broadened by the definition ofeuro-orphan. The Ministry of Education describes the euro-orphan as the destruction of the family structure, the disorder of the socialisation process of children and reduction of the emotional exchanges among family members, as a result of migration of their parents. It provides further that not every child whose parents are not present in the country is covered as an euro-orphan. However, this group has become an increasingly larger populations. Lack of physical proximity and accessibility of important persons may have some psychological and pedagogical implications. These in turn can be shaped over time, into pathological symptoms, which are diagnostic entities in developmental psychiatry. It is not know precisely how many children in Poland are Euro-orphans. The aim of this paper is an attempt to understand the social phenomenon of Euro-orphanhood in the light of the observed psychopathologies of children and adolescents. The case study of the psychotherapy of a patient suffering from the Euro-orphanhood syndrome. Euro-orphanhood is a social phenomenon that generates Euro-orphans with a wide range of psychopathological symptoms classified in different diagnostic categories. The type and intensification of the psychopathological symptoms depend on the quality of relationships with meaningful persons prior to the Euro-orphanhood period. The course of the psychotherapeutic work with Euro-orphans should cover an individual aspect taking into consideration the maturity of defensive mechanisms as well as the work-through of negative feelings cumulated due to becoming a Euro-orphan.

Orphan nuclear receptor TLX contributes to androgen insensitivity in castration-resistant prostate cancer via its repression of androgen receptor transcription.

PubMed

Jia, Lin; Wu, Dinglan; Wang, Yuliang; You, Wenxing; Wang, Zhu; Xiao, Lijia; Cai, Ganhui; Xu, Zhenyu; Zou, Chang; Wang, Fei; Teoh, Jeremy Yuen-Chun; Ng, Chi-Fai; Yu, Shan; Chan, Franky L

2018-03-20

The metastatic castration-resistant prostate cancer (CRPC) is a lethal form of prostate cancer, in which the expression of androgen receptor (AR) is highly heterogeneous. Indeed, lower AR expression and attenuated AR signature activity is shown in CRPC tissues, especially in the subset of neuroendocrine prostate cancer (NEPC) and prostate cancer stem-like cells (PCSCs). However, the significance of AR downregulation in androgen insensitivity and de-differentiation of tumor cells in CRPC is poorly understood and much neglected. Our previous study shows that the orphan nuclear receptor TLX (NR2E1), which is upregulated in prostate cancer, plays an oncogenic role in prostate carcinogenesis by suppressing oncogene-induced senescence. In the present study, we further established that TLX exhibited an increased expression in metastatic CRPC. Further analyses showed that overexpression of TLX could confer resistance to androgen deprivation and anti-androgen in androgen-dependent prostate cancer cells in vitro and in vivo, whereas knockdown of endogenous TLX could potentiate the sensitivity to androgen deprivation and anti-androgen in prostate cancer cells. Our study revealed that the TLX-induced resistance to androgen deprivation and anti-androgen was mediated through its direct suppression of AR gene transcription and signaling in both androgen-stimulated and -unstimulated prostate cancer cells. We also characterized that TLX could bind directly to AR promoter and repress AR transcription by recruitment of histone modifiers, including HDAC1, HDAC3, and LSD1. Together, our present study shows, for the first time, that TLX can contribute to androgen insensitivity in CRPC via repression of AR gene transcription and signaling, and also implicates that targeting the druggable TLX may have a potential therapeutic significance in CRPC management, particularly in NEPC and PCSCs.

Priority setting for orphan drugs: an international comparison.

PubMed

Rosenberg-Yunger, Zahava R S; Daar, Abdallah S; Thorsteinsdóttir, Halla; Martin, Douglas K

2011-04-01

To describe the process of priority setting for two orphan drugs - Cerezyme and Fabrazyme - in Canada, Australia and Israel, in order to understand and improve the process based on stakeholder perspectives. We conducted qualitative case studies of how three independent drug advisory committees made decisions relating to the funding of Cerezyme and Fabrazyme. Interviews were conducted with 22 informants, including committee members, patient groups and industry representatives. (1) DESCRIPTION: Orphan drugs reimbursement recommendations by expert panels were based on clinical evidence, cost and cost-effectiveness analysis. (2) EVALUATION: Committee members expressed an overall preference for the current drug review process used by their own committee, but were concerned with the fairness of the process particularly for orphan drugs. Other informants suggested the inclusion of other relevant values (e.g. lack of alternative treatments) in order to improve the priority setting process. Some patient groups suggested the use of an alternative funding mechanism for orphan drugs. Priority setting for drugs is not solely a technical process (involving cost-effective analysis, evidence-based medicine, etc.). Understanding the process by which reimbursement decisions are made for orphan drugs may help improve the system for future orphan drugs. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Orphan drugs: trends and issues in drug development.

PubMed

Rana, Proteesh; Chawla, Shalini

2018-04-12

Research in rare diseases has contributed substantially toward the current understanding in the pathophysiology of the common diseases. However, medical needs of patients with rare diseases have always been neglected by the society and pharmaceutical industries based on their small numbers and unprofitability. The Orphan Drug Act (1983) was the first serious attempt to address the unmet medical needs for patients with rare diseases and to provide impetus for the pharmaceutical industry to promote orphan drug development. The process of drug development for rare diseases is no different from common diseases but involves significant cost and infrastructure. Further, certain aspect of drug research may not be feasible for the rare diseases. The drug-approving authority must exercise their scientific judgment and ensure due flexibility while evaluating data at various stages of orphan drug development. The emergence of patent cliff combined with the government incentives led the pharmaceutical industry to realize the good commercial prospects in developing an orphan drug despite the small market size. Indeed, many drugs that were given orphan designation ended up being blockbusters. The orphan drug market is projected to reach $178 billion by 2020, and the prospects of research and development in rare diseases appears to be quite promising and rewarding.

Activation of Ftz-F1-Responsive Genes through Ftz/Ftz-F1 Dependent Enhancers

PubMed Central

Field, Amanda; Xiang, Jie; Anderson, W. Ray; Graham, Patricia; Pick, Leslie

2016-01-01

The orphan nuclear receptor Ftz-F1 is expressed in all somatic nuclei in Drosophila embryos, but mutations result in a pair-rule phenotype. This was explained by the interaction of Ftz-F1 with the homeodomain protein Ftz that is expressed in stripes in the primordia of segments missing in either ftz-f1 or ftz mutants. Ftz-F1 and Ftz were shown to physically interact and coordinately activate the expression of ftz itself and engrailed by synergistic binding to composite Ftz-F1/Ftz binding sites. However, attempts to identify additional target genes on the basis of Ftz-F1/ Ftz binding alone has met with only limited success. To discern rules for Ftz-F1 target site selection in vivo and to identify additional target genes, a microarray analysis was performed comparing wildtype and ftz-f1 mutant embryos. Ftz-F1-responsive genes most highly regulated included engrailed and nine additional genes expressed in patterns dependent on both ftz and ftz-f1. Candidate enhancers for these genes were identified by combining BDTNP Ftz ChIP-chip data with a computational search for Ftz-F1 binding sites. Of eight enhancer reporter genes tested in transgenic embryos, six generated expression patterns similar to the corresponding endogenous gene and expression was lost in ftz mutants. These studies identified a new set of Ftz-F1 targets, all of which are co-regulated by Ftz. Comparative analysis of enhancers containing Ftz/Ftz-F1 binding sites that were or were not bona fide targets in vivo suggested that GAF negatively regulates enhancers that contain Ftz/Ftz-F1 binding sites but are not actually utilized. These targets include other regulatory factors as well as genes involved directly in morphogenesis, providing insight into how pair-rule genes establish the body pattern. PMID:27723822

Hereditary Angioedema: The Economics of Treatment of an Orphan Disease.

PubMed

Lumry, William Raymond

2018-01-01

This review will discuss the cost burden of hereditary angioedema on patients, healthcare systems, and society. The impact of availability of and access to novel and specific therapies on morbidity, mortality, and the overall burden of disease will be explored along with potential changes in treatment paradigms to improve effectiveness and reduce cost of treatment. The prevalence of orphan diseases, legislative incentives to encourage development of orphan disease therapies and the impact of orphan disease treatment on healthcare payment systems will be discussed.

National Plans of Action for Orphans and Vulnerable Children in Sub-Saharan Africa. Where Are the Youngest Children? Working Papers in Early Childhood Development, No. 50

ERIC Educational Resources Information Center

Engle, Patrice

2008-01-01

In 2005, an estimated 48 million children aged 0-18 years--12 percent of all children in sub-Saharan Africa--were orphans, and that number is expected to rise to 53 million by 2010. One quarter of all orphans are orphaned because of AIDS, and about 2.6 million children are currently infected with HIV. Untreated, most children born with HIV will…

Pressure for drug development in lysosomal storage disorders - a quantitative analysis thirty years beyond the US orphan drug act.

PubMed

Mechler, Konstantin; Mountford, William K; Hoffmann, Georg F; Ries, Markus

2015-04-18

Lysosomal storage disorders are a heterogeneous group of approximately 50 monogenically inherited orphan conditions. A defect leads to the storage of complex molecules in the lysosome, and patients develop a complex multisystemic phenotype of high morbidity often associated with premature death. More than 30 years ago the Orphan Drug Act of 1983 passed the United States legislation intended to facilitate the development of drugs for rare disorders. We directed our efforts in assessing which lysosomal diseases had drug development pressure and what distinguished those with successful development and approvals from diseases not treated or without orphan drug designation. Analysis of the FDA database for orphan drug designations through descriptive and comparative statistics. Between 1983 and 2013, fourteen drugs for seven conditions received FDA approval. Overall, orphan drug status was designated 70 times for 20 conditions. Approved therapies were enzyme replacement therapies (N = 10), substrate reduction therapies (N = 1), small molecules facilitating lysosomal substrate transportation (N = 3). FDA approval was significantly associated with a disease prevalence higher than 0.5/100,000 (p = 0.00742) and clinical development programs that did not require a primary neurological endpoint (p = 0.00059). Orphan drug status was designated for enzymes, modified enzymes, fusion proteins, chemical chaperones, small molecules leading to substrate reduction, or facilitating subcellular substrate transport, stem cells as well as gene therapies. Drug development focused on more common diseases. Primarily neurological diseases were neglected. Small clinical trials with either somatic or biomarker endpoints were successful. Enzyme replacement therapy was the most successful technology. Four factors played a key role in successful orphan drug development or orphan drug designations: 1) prevalence of disease 2) endpoints 3) regulatory precedent, and 4) technology platform. Successful development seeded further innovation.

Evaluation in zebrafish model of the toxicity of rhodamine B-conjugated crotamine, a peptide potentially useful for diagnostics and therapeutics.

PubMed

Chan, Judy Yuet-Wa; Zhou, Hefeng; Kwan, Yiu Wa; Chan, Shun Wan; Radis-Baptista, Gandhi; Lee, Simon Ming-Yuen

2017-11-01

Crotamine is defensin-like cationic peptide from rattlesnake venom that possesses anticancer, antimicrobial, and antifungal properties. Despite these promising biological activities, toxicity is a major concern associated with the development of venom-derived peptides as therapeutic agents. In the present study, we used zebrafish as a system model to evaluate the toxicity of rhodamine B-conjugated (RhoB) crotamine derivative. The lethal toxic concentration of RhoB-crotamine was as low as 4 μM, which effectively kill zebrafish larvae in less than 10 min. With non-lethal concentrations (<1 μM), crotamine caused malformation in zebrafish embryos, delayed or completely halted hatching, adversely affected embryonic developmental programming, decreased the cardiac functions, and attenuated the swimming distance of zebrafish. The RhoB-crotamine translocated across vitelline membrane and accumulated in zebrafish yolk sac. These results demonstrate the sensitive responsivity of zebrafish to trial crotamine analogues for the development of novel therapeutic peptides with improved safety, bioavailability, and efficacy profiles. © 2017 Wiley Periodicals, Inc.

Lethal genes surviving by mosaicism: a possible explanation for sporadic birth defects involving the skin.

PubMed

Happle, R

1987-04-01

A genetic concept is advanced to explain the origin of several sporadic syndromes characterized by a mosaic distribution of skin defects. It is postulated that these disorders are due to the action of a lethal gene surviving by mosaicism. The presence of the mutation in the zygote will lead to death of the embryo at an early stage of development. Cells bearing the mutation can survive only in a mosaic state, in close proximity with normal cells. The mosaic may arise either from a gametic half chromatid mutation or from an early somatic mutation. This concept of origin is proposed to apply to the Schimmelpenning-Feuerstein-Mims syndrome, the McCune-Albright syndrome, the Klippel-Trenaunay syndrome, the Sturge-Weber syndrome, and neurocutaneous melanosis. Moreover, this etiologic hypothesis may apply to two other birth defects that have recently been delineated, the Proteus syndrome (partial gigantism of hands or feet, hemihypertrophy, macrocephaly, linear papillomatous epidermal nevus, subcutaneous hemangiomas and lipomas, accelerated growth, and visceral anomalies), and the Delleman-Oorthuys syndrome (orbital cyst, porencephaly, periorbital appendages, and focal aplasia of the skin.

Toxic responses of medaka, d-rR strain, to polychlorinated naphthalene mixtures after embryonic exposure by in ovo nanoinjection: A partial life-cycle assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Villalobos, S.A.; Papoulias, D.M.; Meadows, J.

2000-02-01

Polychlorinated naphthalenes (PCNs) are organic compounds with some chemical properties and uses similar to polychlorinated biphenyls. Polychlorinated naphthalenes have been detected in biota from certain aquatic environments. The toxicities of several PCN technical mixtures (Halowax) to medaka (Oryzias latipes) were determined by use of an embryo nanoinjection method. Medaka eggs (early gastrula) were injected with 0.5 nl of triolein (vehicle control) or 0.5 nl of four to five graded doses (0.3--30 ng/egg) of Halowax 1014, Halowax 1013, or Halowax 1051 in triolein. Following exposure, embryos developed, and fry were reared to sexual maturity (4 months), at which time they weremore » euthanized. Responses were evaluated as early life stage (ELS) and early adult life stage (EALS) assessments. For ELS, lethality and sublethal alterations in embryos and larvae (<16 d old), such as craniofacial, cardiovascular, and myoskeletal deformities and abnormal or delayed hatch, were monitored for the first 9 d, and a dose severity index was computed. The EALS assessment examined the survival of 16-d-old larvae until early adulthood (123 {+-} 3 d old), including gonadosomatic index (GSI) and morphometry. Halowax 1014 was found to be the most toxic mixture (LD50 4.2 ng/egg), whereas Halowax 1013 and 1051 were significantly less toxic (LD50s could not be determined). The gonadosomatic index of females was significantly less in fish dosed with Halowax 1014 or 1051. The LD50 for medaka embryos nanoinjected with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is about 0.75 pg/egg. Thus, Halowax 1014 was 5,585-fold less potent than TCDD. For Halowax 1014, ELS assessments accurately predicted the results of EALS assessments.« less

Selective loss of mouse embryos due to the expression of transgenic major histocompatibility class I molecules early in embryogenesis.

PubMed

Aït-Azzouzene, D; Langkopf, A; Cohen, J; Bleux, C; Gendron, M C; Kanellopoulos-Langevin, C

1998-05-01

Among the numerous hypotheses proposed to explain the absence of fetal rejection by the mother in mammals, it has been suggested that regulation of expression of the polymorphic major histocompatibility complex (MHC) at the fetal-maternal interface plays a major role. In addition to a lack of MHC gene expression in the placenta throughout gestation, the absence of polymorphic MHC molecules on the early embryo, as well as their low level of expression after midgestation, could contribute to this important biologic phenomenon. In order to test this hypothesis, we have produced transgenic mice able to express polymorphic MHC class I molecules early in embryogenesis. We have placed the MHC class la gene H-2Kb under the control of a housekeeping gene promoter, the hydroxy-methyl-glutaryl coenzyme A reductase (HMG) gene minimal promoter. This construct has been tested for functionality after transfection into mouse fibroblast L cells. The analysis of three founder transgenic mice and their progeny suggested that fetoplacental units that could express the H-2Kb heavy chains are unable to survive in utero beyond midgestation. We have shown further that a much higher resorption rate, on days 11 to 13 of embryonic development, is observed among transgenic embryos developing from eggs microinjected at the one-cell stage with the pHMG-Kb construct than in control embryos. This lethality is not due to immune phenomena, since it is observed in histocompatible combinations between mother and fetus. These results are discussed in the context of what is currently known about the regulation of MHC expression at the fetal-maternal interface and in various transgenic mouse models.

Cryopreservation of Embryos of the Mediterranean Fruit Fly Ceratitis capitata Vienna 8 Genetic Sexing Strain

PubMed Central

Augustinos, Antonios A.; Rajamohan, Arun; Kyritsis, Georgios A.; Zacharopoulou, Antigone; Haq, Ihsan ul; Targovska, Asya; Caceres, Carlos; Bourtzis, Kostas; Abd-Alla, Adly M. M.

2016-01-01

The Mediterranean fruit fly, Ceratitis capitata, is one of the most serious pests of fruit crops world-wide. During the last decades, area-wide pest management (AW-IPM) approaches with a sterile insect technique (SIT) component have been used to control populations of this pest in an effective and environment-friendly manner. The development of genetic sexing strains (GSS), such as the Vienna 8 strain, has been played a major role in increasing the efficacy and reducing the cost of SIT programs. However, mass rearing, extensive inbreeding, possible bottleneck phenomena and hitch-hiking effects might pose major risks for deterioration and loss of important genetic characteristics of domesticated insect. In the present study, we present a modified procedure to cryopreserve the embryos of the medfly Vienna 8 GSS based on vitrification and used this strain as insect model to assess the impact of the cryopreservation process on the genetic structure of the cryopreserved insects. Forty-eight hours old embryos, incubated at 24°C, were found to be the most suitable developmental stage for cryopreservation treatment for high production of acceptable hatch rate (38%). Our data suggest the absence of any negative impact of the cryopreservation process on egg hatch rate, pupation rates, adult emergence rates and stability of the temperature sensitive lethal (tsl) character on two established cryopreserved lines (flies emerged from cryopreserved embryos), named V8-118 and V8-228. Taken together, our study provides an optimized procedure to cryopreserve the medfly Vienna 8 GSS and documents the absence of any negative impact on the genetic structure and quality of the strain. Benefits and sceneries for utilization of this technology to support operational SIT projects are discussed in this paper. PMID:27537351

Cryopreservation of Embryos of the Mediterranean Fruit Fly Ceratitis capitata Vienna 8 Genetic Sexing Strain.

PubMed

Augustinos, Antonios A; Rajamohan, Arun; Kyritsis, Georgios A; Zacharopoulou, Antigone; Haq, Ihsan Ul; Targovska, Asya; Caceres, Carlos; Bourtzis, Kostas; Abd-Alla, Adly M M

2016-01-01

The Mediterranean fruit fly, Ceratitis capitata, is one of the most serious pests of fruit crops world-wide. During the last decades, area-wide pest management (AW-IPM) approaches with a sterile insect technique (SIT) component have been used to control populations of this pest in an effective and environment-friendly manner. The development of genetic sexing strains (GSS), such as the Vienna 8 strain, has been played a major role in increasing the efficacy and reducing the cost of SIT programs. However, mass rearing, extensive inbreeding, possible bottleneck phenomena and hitch-hiking effects might pose major risks for deterioration and loss of important genetic characteristics of domesticated insect. In the present study, we present a modified procedure to cryopreserve the embryos of the medfly Vienna 8 GSS based on vitrification and used this strain as insect model to assess the impact of the cryopreservation process on the genetic structure of the cryopreserved insects. Forty-eight hours old embryos, incubated at 24°C, were found to be the most suitable developmental stage for cryopreservation treatment for high production of acceptable hatch rate (38%). Our data suggest the absence of any negative impact of the cryopreservation process on egg hatch rate, pupation rates, adult emergence rates and stability of the temperature sensitive lethal (tsl) character on two established cryopreserved lines (flies emerged from cryopreserved embryos), named V8-118 and V8-228. Taken together, our study provides an optimized procedure to cryopreserve the medfly Vienna 8 GSS and documents the absence of any negative impact on the genetic structure and quality of the strain. Benefits and sceneries for utilization of this technology to support operational SIT projects are discussed in this paper.

A modified acetylcholine receptor δ-subunit enables a null mutant to survive beyond sexual maturation

PubMed Central

Epley, Kimberly E.; Urban, Jason M.; Ikenaga, Takanori; Ono, Fumihito

2008-01-01

The contraction of skeletal muscle is dependent upon synaptic transmission through acetylcholine receptors (AChRs) at the neuromuscular junction (NMJ). The lack of an AChR subunit causes a fetal akinesia in humans, leading to death in the first trimester and characteristic features of Fetal Akinesia Deformation Sequences (FADS). A corresponding null mutation of the δ-subunit in zebrafish (sofa potato; sop−/−) leads to the death of embryos around 5 days post-fertilization (dpf). In sop−/− mutants, we expressed modified δ-subunits, with one (δ1YFP) or two yellow fluorescent protein (δ2YFP) molecules fused at the intracellular loop, under the control of an α-actin promoter. AChRs containing these fusion proteins are fluorescent, assemble on the plasma membrane, make clusters under motor neuron endings, and generate synaptic current. We screened for germ-line transmission of the transgene and established a line of sop−/− fish stably expressing the δ2YFP. These δ2YFP/sop−/− embryos can mount escape behavior close to that of their wild type siblings. Synaptic currents in these embryos had a smaller amplitude, slower rise time, and slower decay when compared to wild type fish. Remarkably, these embryos grow to adulthood and display complex behaviors such as feeding and breeding. To the best of our knowledge, this is the first case of a mutant animal corresponding to first trimester lethality in human that has been rescued by a transgene and survived to adulthood. In the rescued fish, a foreign promoter drove the transgene expression and the NMJ had altered synaptic strength. The survival of the transgenic animal delineates requirements for gene therapies of NMJ. PMID:19052214

Developmental and metabolic responses of zebrafish (Danio rerio) embryos and larvae to short-chain chlorinated paraffins (SCCPs) exposure.

PubMed

Ren, Xiaoqian; Zhang, Haijun; Geng, Ningbo; Xing, Liguo; Zhao, Yu; Wang, Feidi; Chen, Jiping

2018-05-01

Short-chain chlorinated paraffins (SCCPs) are highly toxic to aquatic organisms, but their toxicity is yet not well characterized. In this study, the developmental toxicity of SCCPs to zebrafish embryos/larvae was evaluated, and a metabolomics approach was adopted to explore the impact of SCCPs exposure on the metabolism in zebrafish embryos. Exposure to SCCPs at concentrations of 1-200μg/L did not produce an observable effect on the hatching rate and morphological deformities of zebrafish embryos/larvae. However, the survival rate of zebrafish larvae in SCCPs exposure groups decreased in a concentration-dependent manner. The 13-day 50% lethal concentration (LC 50 ) value of SCCPs was calculated to be 34.4μg/L. Exposure to SCCPs induced a significant change of overall metabolism, even at environmentally relevant concentrations (1-5μg/L). The most relevant pathways affected by SCCPs exposure were glycerophospholipid metabolism, fatty acid metabolism and purine metabolism. Exposure to SCCPs at concentrations of 1-5μg/L had begun to accelerate the β-oxidation of unsaturated fatty acids and very long chain fatty acids, and affect the transformation of guanine to xanthine in the pathway of purine metabolism. Furthermore, when the exposure concentrations of SCCPs were increased to 50-200μg/L, the levels of phospholipids and amino acids were significantly raised; whereas the levels of fatty acids, carnitines and inosine were significantly decreased. In view of the significant effect on metabolism, the sub-chronic and chronic toxicity of SCCPs to fish should be concerned. Copyright © 2017 Elsevier B.V. All rights reserved.

Toxic responses of medaka, D-rR strain, to polychlorinatednaphthalene mixtures after embryonic exposure by in ovo nanoinjection: A partial life-cycle assessment

USGS Publications Warehouse

Villalobos, Sergio A.; Papoulias, Diana M.; Meadows, John C.; Blankenship, Alan L.; Pastva, Stephanie D.; Kannan, Kurunthachalam; Hinton, D.E.; Tillitt, Donald E.; Giesy, John P.

2000-01-01

Polychlorinated naphthalenes (PCNs) are organic compounds with some chemical properties and uses similar to polychlorinated biphenyls. Polychlorinated naphthalenes have been detected in biota from certain aquatic environments. The toxicities of several PCN technical mixtures (Halowax) to medaka (Oryzias latipes) were determined by use of an embryo nanoinjection method. Medaka eggs (early gastrula) were injected with 0.5 nl of triolein (vehicle control) or 0.5 nl of four to five graded doses (0.3-30 ng/egg) of Halowax 1014, Halowax 1013, or Halowax 1051 in triolein. Following exposure, embryos developed, and fry were reared to sexual maturity (4 months), at which time they were euthanized. Responses were evaluated as early life stage (ELS) and early adult life stage (EALS) assessments. For ELS, lethality and sublethal alterations in embryos and larvae ( < 16 d old), such as craniofacial, cardiovascular, and myoskeletal deformities and abnormal or delayed hatch, were monitored for the first 9 d, and a dose severity index was computed. The EALS assessment examined the survival of 16-d-old larvae until early adulthood (123 ?? 3 d old), including gonadosomatic index (GSI) and morphometry. Halowax 1014 was found to be the most toxic mixture (LD50 4.2 ng/egg), whereas Halowax 1013 and 1051 were significantly less toxic (LD50s could not be determined). The gonadosomatic index of females was significantly less in fish dosed with Halowax 1014 or 1051. The LD50 for medaka embryos nanoinjected with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is about 0.75 pg/egg. Thus, Halowax 1014 was 5,585-fold less potent than TCDD. For Halowax 1014, ELS assessments accurately predicted the results of EALS assessments.

The use of plant stress biomarkers in assessing the effects of desiccation in zygotic embryos from recalcitrant seeds: challenges and considerations.

PubMed

Sershen; Varghese, B; Naidoo, C; Pammenter, N W

2016-05-01

Zygotic embryos from recalcitrant seeds are sensitive to desiccation. In spite of their sensitivity, rapid partial dehydration is necessary for their successful cryopreservation. However, dehydration to water contents (WCs) that preclude lethal ice crystal formation during cooling and rewarming generally leads to desiccation damage. This study investigated the effects of rapid dehydration on selected stress biomarkers (electrolyte leakage, respiratory competence, rate of protein synthesis, superoxide production, lipid peroxidation, antioxidant activity and degree of cellular vacuolation) in zygotic embryos of four recalcitrant-seeded species. Most biomarkers indicated differences in the levels of stress/damage incurred by embryos dried to WCs < and >0.4 g·g(-1) , within species; however, these changes were often unrelated to viability and percentage water loss when data for the four species were pooled for regression analyses. Dehydration-induced electrolyte leakage was, however, positively related with percentage water loss, while biomarkers of cellular vacuolation were positively related with both percentage water loss and viability. This suggests that electrolyte leakage and degree of cellular vacuolation can be used to quantify dehydration-induced stress/damage. Biomarkers such as superoxide production, whilst useful in establishing the nature of the dehydration stress incurred may not be able to distinguish the effects of different WCs/drying times. Irrespective of which biomarker is used, the data suggest that understanding differences in desiccation sensitivity across recalcitrant-seeded species will remain a challenge unless these biomarkers are related to a generic desiccation stress index that integrates the effects of percentage water loss and drying time. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

Cardio-respirometry disruption in zebrafish (Danio rerio) embryos exposed to hydraulic fracturing flowback and produced water.

PubMed

Folkerts, Erik J; Blewett, Tamzin A; He, Yuhe; Goss, Greg G

2017-12-01

Hydraulic fracturing to extract oil and natural gas reserves is an increasing practice in many international energy sectors. Hydraulic fracturing flowback and produced water (FPW) is a hyper saline wastewater returned to the surface from a fractured well containing chemical species present in the initial fracturing fluid, geogenic contaminants, and potentially newly synthesized chemicals formed in the fracturing well environment. However, information on FPW toxicological mechanisms of action remain largely unknown. Both cardiotoxic and respirometric responses were explored in zebrafish (Danio rerio) embryos after either an acute sediment-free (FPW-SF) or raw/sediment containing (FPW-S) fraction exposure of 24 and 48 h at 2.5% and 5% dilutions. A 48 h exposure to either FPW fraction in 24-72 h post fertilization zebrafish embryos significantly increased occurrences of pericardial edema, yolk-sac edema, and tail/spine curvature. In contrast, larval heart rates significantly decreased after FPW fraction exposures. FPW-S, but not FPW-SF, at 2.5% doses significantly reduced embryonic respiration/metabolic rates (MO 2 ), while for 5% FPW, both fractions reduced MO 2 . Expression of select cardiac genes were also significantly altered in each FPW exposure group, implicating a cardiovascular system compromise as the potential cause for reduced embryonic MO 2 . Collectively, these results support our hypothesis that organics are major contributors to cardiac and respiratory responses to FPW exposure in zebrafish embryos. Our study is the first to investigate cardiac and respiratory sub-lethal effects of FPW exposure, demonstrating that FPW effects extend beyond initial osmotic stressors and verifies the use of respirometry as a potential marker for FPW exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

Production of a compound against methicillin resistant Staphylococcus aureus (MRSA) from Streptomyces rubrolavendulae ICN3 & its evaluation in zebrafish embryos

PubMed Central

Kannan, Rajaretinam Rajesh; Iniyan, Appadurai Muthamil; Vincent, Samuel Gnana Prakash

2014-01-01

Background & objectives: Antibiotic resistance in pathogens has become a serious problem worldwide. Therefore, the search for new antibiotics for drug resistanct pathogens is an important endeavor. The present study deals with the production of anti-methicillin resistant Staphylococcus aureus (MRSA) potential of Streptomyces rubrolavendulae ICN3 and evaluation of anti-MRSA compound in zebrafish embryos. Methods: The antibiotic production from S. rubrolavendulae ICN3 was optimized in solid state fermentation and extracted. The antagonistic activity was confirmed against MRSA and purified in silica gel column and reverse phase - HPLC with an absorption maximum at 215 nm. Minimal inhibitory concentration of the compound was determined by broth microdilution method. Zebrafish embryos were used to evaluate the extract/compound for its minimal inhibition studies, influences on heart beat rates, haematopoietic blood cell count and lethal dose values. Results: Streptomyces rubrolavendulae ICN3 showed potent antagonistic activity against MRSA with a zone of 42 mm. The minimum inhibitory concentration was calculated as 500 μg/ml of the crude extract and the purified C23 exhibited 2.5 μg/ml in in vitro assay. The LC50 value of the anti MRSA compound C23 was calculated as 60.49 μg/ml and the MRSA treated embryos survived in the presence of purified compound C23 at a dose of 10 μg/ml. Interpretation & conclusions: Our results suggested that the compound was potent with less toxic effects in zebrafish embryonic model system for MRSA infection. Further structural evaluation and analysis in higher mammalian model system may lead to a novel drug candidate for drug resistant Staphylococcus aureus. PMID:25109726

Evaluating the Teratogenicity of Ritodrine and Nifedipine using a Frog Embryo Teratogenesis assay (FETAX).

PubMed

Boğa Pekmezekmek, Ayper; Binokay, Uğur Seçil; Seçilmiş, Mehmet Ata; Kumcu, Eda; Şimşek, Erhan; Akillioğlu, Kübra; Sertdemir, Yaşar; Özaykan, Besim

2015-01-01

The Frog Embryo Teratogenesis Assay-Xenopus (FETAX) was used to assess the teratogenic potential of two tocolytics. Embryos of the South African clawed frog, Xenopus laevis, were exposed to ritodrine or nifedipine. Exposure media were changed and monitored at 24-hour intervals. The 96-hour LC50 (Lethal concentration), the 96-hour EC50 (Malformation), and the No Observable Adverse Effect Concentrations (NOAEC) and the Lowest Observable Adverse Effect Concentration (LOAEC) for mortality, malformation and length were determined for each drug. Nifedipine was determined to be the more toxic and teratogenic than ritodrine, with a LC50 of 0.606 µg/L, an EC50 of 0.006 µg/L, and a teratogenicity Index (TI) value (LC50/EC50) of 101. On the other hand, the LC50 of ritodrine was 28.571 mg/L. In addition; the LC50, EC50 and TI values for nifedipine in the 5 mg/L ritodrine + nifedipine combination group were determined as 1.050 µg/L, 0.868 µg/L and 1.5 respectively. For ritodrine, the NOAEC and LOAEC values were determined as 2 mg/L and 4 mg/L, respectively. For the nifedipine and the ritodrine + nifedipine groups; while the LOAEC values of these groups were 0.0001 µg/L and 0.1 µg/L, respectively. NOAEC value couldn't be determined. Our results demonstrated that nifedipine administration was associated with higher levels of teratogenic and toxic effects. However, the ritodrine + nifedipine combination form reduced the toxic and teratogenic effects of nifedipine on Xenopus embryos. Further studies should be conducted in order to investigate the optimal combination concentrations of these substances for the treatment of preterm labor.

Redundant functions of I-BAR family members, IRSp53 and IRTKS, are essential for embryonic development

PubMed Central

Chou, Ai Mei; Sem, Kai Ping; Lam, Wei Jun; Ahmed, Sohail; Lim, Chin Yan

2017-01-01

The insulin receptor substrate of 53 kDa, IRSp53, is an adaptor protein that works with activated GTPases, Cdc42 and Rac, to modulate actin dynamics and generate membrane protrusions in response to cell signaling. Adult mice that lack IRSp53 fail to regulate synaptic plasticity and exhibit hippocampus-associated learning deficiencies. Here, we show that 60% of IRSp53 null embryos die at mid to late gestation, indicating a vital IRSp53 function in embryonic development. We find that IRSp53 KO embryos displayed pleiotropic phenotypes such as developmental delay, oligodactyly and subcutaneous edema, and died of severely impaired cardiac and placental development. We further show that double knockout of IRSp53 and its closest family member, IRTKS, resulted in exacerbated placental abnormalities, particularly in spongiotrophoblast differentiation and development, giving rise to complete embryonic lethality. Hence, our findings demonstrate a hitherto under-appreciated IRSp53 function in embryonic development, and further establish an essential genetic interaction between IRSp53 and IRTKS in placental formation. PMID:28067313

The thyroid hormone receptor-associated protein TRAP220 is required at distinct embryonic stages in placental, cardiac, and hepatic development.

PubMed

Landles, Christian; Chalk, Sara; Steel, Jennifer H; Rosewell, Ian; Spencer-Dene, Bradley; Lalani, El-Nasir; Parker, Malcolm G

2003-12-01

Recent work indicates that thyroid hormone receptor-associated protein 220 (TRAP220), a subunit of the multiprotein TRAP coactivator complex, is essential for embryonic survival. We have generated TRAP220 conditional null mice that are hypomorphic and express the gene at reduced levels. In contrast to TRAP220 null mice, which die at embryonic d 11.5 (E11.5), hypomorphic mice survive until E13.5. The reduced expression in hypomorphs results in hepatic necrosis, defects in hematopoiesis, and hypoplasia of the ventricular myocardium, similar to that observed in TRAP220 null embryos at an earlier stage. The embryonic lethality of null embryos at E11.5 is due to placental insufficiency. Tetraploid aggregation assays partially rescues embryonic development until E13.5, when embryonic loss occurs due to hepatic necrosis coupled with poor myocardial development as observed in hypomorphs. These findings demonstrate that, for normal placental function, there is an absolute requirement for TRAP220 in extraembryonic tissues at E11.5, with an additional requirement in embryonic tissues for hepatic and cardiovascular development thereafter.

Polyspermy in birds: sperm numbers and embryo survival

PubMed Central

Hemmings, N.; Birkhead, T. R.

2015-01-01

Polyspermy is a major puzzle in reproductive biology. In some taxa, multiple sperm enter the ovum as part of the normal fertilization process, whereas in others, penetration of the ovum by more than one sperm is lethal. In birds, several sperm typically enter the germinal disc, yet only one fuses with the female pronucleus. It is unclear whether supernumerary sperm play an essential role in the avian fertilization process and, if they do, how females regulate the progression of sperm through the oviduct to ensure an appropriate number reach the ovum. Here, we show that when very few sperm penetrate the avian ovum, embryos are unlikely to survive beyond the earliest stages of development. We also show that when the number of inseminated sperm is limited, a greater proportion than expected reach and penetrate the ovum, indicating that females compensate for low sperm numbers in the oviduct. Our results suggest a functional role for supernumerary sperm in the processes of fertilization and early embryogenesis, providing an exciting expansion of our understanding of sperm function in birds. PMID:26511048

Placental labyrinth formation in mice requires endothelial FLRT2/UNC5B signaling.

PubMed

Tai-Nagara, Ikue; Yoshikawa, Yusuke; Numata, Naoko; Ando, Tomofumi; Okabe, Keisuke; Sugiura, Yuki; Ieda, Masaki; Takakura, Nobuyuki; Nakagawa, Osamu; Zhou, Bin; Okabayashi, Koji; Suematsu, Makoto; Kitagawa, Yuko; Bastmeyer, Martin; Sato, Kohji; Klein, Rüdiger; Navankasattusas, Sutip; Li, Dean Y; Yamagishi, Satoru; Kubota, Yoshiaki

2017-07-01

The placental labyrinth is the interface for gas and nutrient exchange between the embryo and the mother; hence its proper development is essential for embryogenesis. However, the molecular mechanism underlying development of the placental labyrinth, particularly in terms of its endothelial organization, is not well understood. Here, we determined that fibronectin leucine-rich transmembrane protein 2 (FLRT2), a repulsive ligand of the UNC5 receptor family for neurons, is unexpectedly expressed in endothelial cells specifically in the placental labyrinth. Mice lacking FLRT2 in endothelial cells exhibited embryonic lethality at mid-gestation, with systemic congestion and hypoxia. Although they lacked apparent deformities in the embryonic vasculature and heart, the placental labyrinths of these embryos exhibited aberrant alignment of endothelial cells, which disturbed the feto-maternal circulation. Interestingly, this vascular deformity was related to endothelial repulsion through binding to the UNC5B receptor. Our results suggest that the proper organization of the placental labyrinth depends on coordinated inter-endothelial repulsion, which prevents uncontrolled layering of the endothelium. © 2017. Published by The Company of Biologists Ltd.

The role of platelets during reproduction.

PubMed

Isermann, Berend; Nawroth, Peter P

2006-01-01

The availability of mice with defined defects within the hemostatic system enabled researchers to identify a role the coagulation system for embryonic and placental development. However, the role of platelets during development has only recently been experimentally addressed, giving some insight into potential functions of platelets during development. Thus, a quantitative embryonic platelet defect (severe thrombopenia secondary to NF-E2 deficiency) is associated with an embryonic growth retardation and reduced vascularisation of the placenta. Maternal platelet deficiency is associated with placental hemorrhage, which, however, does not impair embryonic or maternal survival. In vitro studies established that platelets or platelet conditioned medium regulate the invasive properties of human extravillous trophoblast cells and induce a phenotypical switch of trophoblast cells. These data imply that platelets are of relevance during placentation. Conversely, platelets and the formation of platelet-fibrin aggregates are dispensable for the development of the embryo proper, establishing that the lethal phenotypes observed in some embryo slacking coagulation regulators does not result from an inability to form platelet-fibrin aggregates, but likely reflects altered protease dependent signaling during vascular development.

The importance of both potency and mechanism in dose-response analysis: an example from exposure of Pacific herring (Clupea pallasi) embryos to low concentrations of weathered crude oil.

PubMed

Neff, Jerry M; Page, David S; Landrum, Peter F; Chapman, Peter M

2013-02-15

This paper reanalyzes data from an earlier study that used effluents from oiled-gravel columns to assess the toxicity of aqueous fractions of weathered crude oil to Pacific herring embryos and larvae. This reanalysis has implications for future similar investigations, including the observance of two distinct dose-response curves for lethal and sublethal endpoints for different exposures in the same experiment, and the need to consider both potency and slope of dose-response curves for components of a toxicant mixture that shows potentially different toxicity mechanisms/causation. Contrary to conclusions of the original study, the aqueous concentration data cannot support the hypothesis that polycyclic aromatic hydrocarbons (PAHs) were the sole cause of toxicity and that oil toxicity increased with weathering. Confounding issues associated with the oiled gravel columns include changes in the concentration and composition of chemicals in exposure water, which interfere with the production of reliable and reproducible results relevant to the field. Copyright © 2012 Elsevier Ltd. All rights reserved.

Susceptibility of early life stages of Xenopus laevis to cadmium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herkovits, J.; Perez-Coll, C.S.; Cardellini, P.

1997-02-01

The susceptibility of Xenopus laevis to cadmium during different stages of development was evaluated by exposing embryos to cadmium concentrations ranging from 0.1 to 10 mg Cd{sup 2+}/L for 24, 48, and 72 h and assessing lethality and malformations. Susceptibility increased from the two blastomeres stage (stage 2) to stage 40, in which the 24-h LC100 was 1.13 mg Cd{sup 2+}/L, and resistance increased from this stage onward. Malformations occurred at all developmental stages evaluated, the most common being reduced size, incurvated axis, underdeveloped or abnormally developed fin, microcephaly, and microphtalmy. Scanning electron microscopy revealed changes in the ectodermal surfacemore » ranging from slightly vaulted cells to a severe reduction in the number of ciliated cells as the concentration of cadmium increased. The intraspecific variation evaluated in embryos (from four sets of parents) at seven developmental stages, expressed as the coefficient of variation of the LC100, ranged from 10 to 112% and reflects the capacity of Xenopus laevis to adapt to changing environmental conditions at different embryonic stages.« less

Monitoring of toxicity of As(V) solutions by AMPHITOX test without and with treatment with zerovalent iron nanoparticles.

PubMed

Pérez Coll, Cristina S; Pabón-Reyes, Carolina; Meichtry, Jorge M; Litter, Marta I

2018-06-01

Changes in toxicity of As(V) solutions from acute to chronic exposure have been evaluated by the AMPHITOX test. This test employs Rhinella arenarum, a widely distributed toad in Argentine areas. LOEC values were 6.37 and 1.88 mg L -1 for embryos and larvae, respectively, and serious sublethal effects have been observed. Toxicity of As(V) solutions has been also evaluated after treatment with zerovalent iron nanoparticles (nZVI). After 60 min of treatment with nZVI, As(V) removal was 77%, and neither lethal nor sublethal effects were observed. However, nZVI had to be eliminated before the bioassay because they caused adverse effects in both embryos and larvae. This work highlights the high sensitivity of R. arenarum to As(V), the relevance to assess toxicity on different periods of the lifecycle, and the need to expand exposure to As(V) to chronic times. The utility of the test for monitoring toxicity changes in As(V) solutions after nZVI treatment has been also shown. Copyright © 2018 Elsevier B.V. All rights reserved.

The importance of SERINE DECARBOXYLASE1 (SDC1) and ethanolamine biosynthesis during embryogenesis of Arabidopsis thaliana.

PubMed

Yunus, Ian Sofian; Liu, Yu-Chi; Nakamura, Yuki

2016-11-01

In plants, ethanolamine is considered a precursor for the synthesis of choline, which is an essential dietary nutrient for animals. An enzyme serine decarboxylase (SDC) has been identified and characterized in Arabidopsis, which directly converts serine to ethanolamine, a precursor to phosphorylethanolamine and its subsequent metabolites in plants. However, the importance of SDC and ethanolamine production in plant growth and development remains unclear. Here, we show that SDC is required for ethanolamine biosynthesis in vivo and essential in plant embryogenesis in Arabidopsis. The knockout of SDC1 caused an embryonic lethal defect due to the developmental arrest of the embryos at the heart stage. During embryo development, the expression was observed at the later stages, at which developmental defect occurred in the knockout mutant. Overexpression of SDC1 in planta increased levels of ethanolamine, phosphatidylethanolamine, and phosphatidylcholine both in leaves and siliques. These results suggest that SDC1 plays an essential role in ethanolamine biosynthesis during the embryogenesis in Arabidopsis. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

Orphan drug development in the United States.

PubMed

Groft, S C

1985-05-01

Drug research and development in the U.S. tends to focus on drugs to treat common diseases because of the anticipated return on investment. To stimulate pharmaceutical manufacturers to pursue the development of drugs for rare conditions, the Orphan Drug Act was enacted by Congress on January 4, 1983. Under the provisions of this Act, the FDA can make recommendations on the investigations necessary for marketing approval; exclusive marketing privileges can be obtained; tax credits for expenses incurred are allowed; availability of orphan drugs on an investigational basis is encouraged; and the Orphan Product Board is established for the coordination of research efforts and their reimbursement. The effects of this legislation are evident in the continuing increase in orphan drug designations.

78 FR 35117 - Orphan Drug Regulations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-12

...The Food and Drug Administration (FDA) is issuing final regulations amending the 1992 Orphan Drug Regulations issued to implement the Orphan Drug Act. These amendments are intended to clarify regulatory provisions and make minor improvements to address issues that have arisen since those regulations were issued.

The Use of Social Media in Orphan Drug Development.

PubMed

Milne, Christopher-Paul; Ni, Wendi

2017-11-01

Social media has transformed how people interact with one another through the Internet, and it has the potential to do the same for orphan drug development. Currently, social media influences the orphan drug development process in the following three ways: assisting the study of orphan diseases, increasing the awareness of orphan disease, and playing a vital role in clinical trials. However, there are some caveats to the utilization of social media, such as the need to protect patient privacy by adequately de-identifying personal health information, assuring consistent quality and representativeness of the data, and preventing the unblinding of patient group assignments. Social media has both potential for improving orphan drug development and pitfalls, but with proper oversight on the part of companies, support and participation of patients and their advocacy groups, and timely guidance from regulatory authorities, the positives outweigh the negatives for this powerful and patient-centric tool. Copyright © 2017 Elsevier HS Journals, Inc. All rights reserved.

Parental HIV/AIDS and psychosocial adjustment among rural Chinese children.

PubMed

Fang, Xiaoyi; Li, Xiaoming; Stanton, Bonita; Hong, Yan; Zhang, Liying; Zhao, Guoxiang; Zhao, Junfeng; Lin, Xiuyun; Lin, Danhua

2009-01-01

To assess the relationship between parental HIV/AIDS and psychosocial adjustment of children in rural central China. Participants included 296 double AIDS orphans (children who had lost both their parents to AIDS), 459 single orphans (children who had lost one parent to AIDS), 466 vulnerable children who lived with HIV-infected parents, and 404 comparison children who did not experience HIV/AIDS-related illness and death in their families. The measures included depressive symptoms, loneliness, self-esteem, future expectations, hopefulness about the future, and perceived control over the future. AIDS orphans and vulnerable children consistently demonstrated poorer psychosocial adjustment than comparison children in the same community. The level of psychosocial adjustment was similar between single orphans and double orphans, but differed by care arrangement among double orphans. The findings underscore the urgency and importance of culturally and developmentally appropriate intervention efforts targeting psychosocial problems among children affected by AIDS and call for more exploration of risk and resilience factors, both individual and contextual, affecting the psychosocial wellbeing of these children.

Diagnostic orphans: comparing self-report lifetime course to groups with DSM-IV alcohol abuse and dependence.

PubMed

McBride, Orla; Adamson, Gary; Bunting, Brendan; McCann, Siobhan

2009-01-01

Research has highlighted the significant alcohol symptoms and mental health problems experienced by diagnostic orphans - individuals who experience 1-2 criteria of DSM-IV alcohol dependence but do not meet the criteria for a DSM-IV alcohol use disorder. This study used a sub-sample (n=34827) from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), and formed mutually exclusive groups to compare the self-report retrospective course of diagnostic orphans to individuals with DSM-IV abuse and dependence. Multinomial logistic regressions were conducted to examine the associations between the groups and a range of demographic and clinical variables. Collectively, the findings demonstrate that diagnostic orphans shared similar characteristics to the abuse and dependence groups, but appeared to experience specific comorbid mental health problems. Orphan status has the potential to be a persistent condition and may result in significant dysfunction. In conclusion, diagnostic orphans represent a distinct group that may benefit from cost-effective treatment or intervention, designed to prevent the escalation of alcohol symptoms.

Budget impact analysis of drugs for ultra-orphan non-oncological diseases in Europe.

PubMed

Schlander, Michael; Adarkwah, Charles Christian; Gandjour, Afschin

2015-02-01

Ultra-orphan diseases (UODs) have been defined by a prevalence of less than 1 per 50,000 persons. However, little is known about budget impact of ultra-orphan drugs. For analysis, the budget impact analysis (BIA) had a time horizon of 10 years (2012-2021) and a pan-European payer's perspective, based on prevalence data for UODs for which patented drugs are available and/or for which drugs are in clinical development. A total of 18 drugs under patent protection or orphan drug designation for non-oncological UODs were identified. Furthermore, 29 ultra-orphan drugs for non-oncological diseases under development that have the potential of reaching the market by 2021 were found. Total budget impact over 10 years was estimated to be €15,660 and €4965 million for approved and pipeline ultra-orphan drugs, respectively (total: €20,625 million). The analysis does not support concerns regarding an uncontrolled growth in expenditures for drugs for UODs.

Developing treatments for inborn errors: incentives available to the clinician.

PubMed

Haffner, Marlene E

2004-04-01

Disorders resulting from inborn errors of metabolism (IEM) affect very small numbers of individuals. The entire population, however, of patients suffering the results of inherited metabolic disorders is large, and has been of increasing concern to patient groups and health care professionals in the United States as well as other countries throughout the world. The 1983 US Orphan Drug Act (ODA) serves to facilitate the development of drugs to treat rare diseases by providing several economic incentives. The sponsor of a product designated as an orphan by the Food & Drugs Administration (FDA) Office of Orphan Products Development (OPD) qualifies for tax credits on clinical trial expenses, the award of grant funding by FDA, through the OPD, and 7 years of marketing exclusivity for a designated drug, or biological product that receives FDA market approval. Orphan drug legislation in the US has benefited victims of IEM by encouraging development of drugs for metabolic deficiencies affecting populations that otherwise would be ignored. America's solution to the orphan drug problem has had worldwide impact. The success of this legislation was a factor leading to the 1993 orphan drug law in Japan; the 1997 implementation of a process whereby most FDA-approved orphan drugs and biological products will be similarly approved in Australia; and, in 1999, regulation on orphan medicinal products in the European Union (EU). Today, international support for rare disease research is providing stimulus and motivation to overcome the financial barriers and encourage development of treatment for very rare diseases throughout the world.

Paying for the Orphan Drug System: break or bend? Is it time for a new evaluation system for payers in Europe to take account of new rare disease treatments?

PubMed Central

2012-01-01

Since its enactment in 2000, the European Orphan Medicinal Products Regulation has allowed the review and approval of approaching 70 treatments for some 55 different conditions in Europe. Success does not come without a price, however. Many of these so-called “orphan drugs” have higher price points than treatments for more common diseases. This has been raising debate as to whether the treatments are worth it, which, in turn risks blocking patient access to treatment. To date, orphan drugs have only accounted for a small percentage of the overall drug budget. It would appear that, with increasing numbers of orphan drugs, governments are concerned about the future budget impact and their cost-effectiveness in comparison with other healthcare interventions. Orphan drugs are under the spotlight, something that is likely to continue as the economic crisis in Europe takes hold and governments respond with austerity measures that include cuts to healthcare expenditures. Formally and informally, governments are looking at how they are going to handle orphan drugs in the future. Collaborative proposals between EU governments to better understand the value of orphan drugs are under consideration. In recent years there has been increasing criticism of behaviours in the orphan drug field, mainly centring on two key perceptions of the system: the high prices of orphan drugs and their inability to meet standard cost-effectiveness thresholds; and the construct of the system itself, which allows companies to gain the benefits that accrue from being badged as an orphan drug. The authors hypothesise that, by examining these criticisms individually, one might be able to turn these different “behaviours” into criteria for the creation of a system to evaluate new orphan drugs coming onto the market. It has been acknowledged that standard methodologies for Health Technology Assessments (HTA) will need to be tailored to take into account the specificities of orphan drugs given that the higher price-points claimed by orphan drugs are unlikely to meet current cost-effectiveness thresholds. The authors propose the development of a new assessment system based on several evaluation criteria, which would serve as a tool for Member State governments to evaluate each new orphan drug at the time of pricing and reimbursement. These should include rarity, disease severity, the availability of other alternatives (level of unmet medical need), the level of impact on the condition that the new treatment offers, whether the product can be used in one or more indications, the level of research undertaken by the developer, together with other factors, such as manufacturing complexity and follow-up measures required by regulatory or other authorities. This will allow governments to value an orphan drug that fulfilled all the criteria very differently from one that only met some of them. An individual country could determine the (monetary) value that it places on each of the different criteria, according to societal preferences, the national healthcare system and the resources at its disposal – each individual government deciding on the weighting attributed to each of the criteria in question, based on what each individual society values most. Such a systematic and transparent system will help frame a more structured dialogue between manufacturers and payers, with the involvement of the treating physicians and the patients; and foster a more certain environment to stimulate continued investment in the field. A new approach could also offer pricing and reimbursement decision-makers a tool to handle the different characteristics amongst new orphan drugs and to redistribute the national budgets in accordance with the outcome of a differentiated assessment. The authors believe that this could, therefore, facilitate the approach for all stakeholders. PMID:23013790

8 CFR 204.3 - Orphan cases under section 101(b)(1)(F) of the Act (non-Convention cases).

Code of Federal Regulations, 2013 CFR

2013-01-01

... advanced processing application (or the advanced processing application concurrently with the orphan... home study preparer and/or fingerprint check. Advanced processing application means Form I-600A (Application for Advanced Processing of Orphan Petition) completed in accordance with the form's instructions...

8 CFR 204.3 - Orphan cases under section 101(b)(1)(F) of the Act (non-Convention cases).

Code of Federal Regulations, 2010 CFR

2010-01-01

... advanced processing application (or the advanced processing application concurrently with the orphan... home study preparer and/or fingerprint check. Advanced processing application means Form I-600A (Application for Advanced Processing of Orphan Petition) completed in accordance with the form's instructions...

8 CFR 204.3 - Orphan cases under section 101(b)(1)(F) of the Act (non-Convention cases).

Code of Federal Regulations, 2014 CFR

2014-01-01

... advanced processing application (or the advanced processing application concurrently with the orphan... home study preparer and/or fingerprint check. Advanced processing application means Form I-600A (Application for Advanced Processing of Orphan Petition) completed in accordance with the form's instructions...

8 CFR 204.3 - Orphan cases under section 101(b)(1)(F) of the Act (non-Convention cases).

Code of Federal Regulations, 2011 CFR

2011-01-01

... advanced processing application (or the advanced processing application concurrently with the orphan... home study preparer and/or fingerprint check. Advanced processing application means Form I-600A (Application for Advanced Processing of Orphan Petition) completed in accordance with the form's instructions...

8 CFR 204.3 - Orphan cases under section 101(b)(1)(F) of the Act (non-Convention cases).

Code of Federal Regulations, 2012 CFR

2012-01-01

... advanced processing application (or the advanced processing application concurrently with the orphan... home study preparer and/or fingerprint check. Advanced processing application means Form I-600A (Application for Advanced Processing of Orphan Petition) completed in accordance with the form's instructions...

Educational Inequalities and Ukrainian Orphans' Future Pathways: Social Reproduction or Transformation through the Hidden Curriculum?

ERIC Educational Resources Information Center

Korzh, Alla

2013-01-01

This qualitative multi-site case study, situated in the context of Ukraine's post-Soviet political economy, examined how orphanage educators' expectations and beliefs about orphans' academic abilities and potential, curriculum, peer relationships, and education policy shaped orphans' post-secondary education decisions and trajectories. Examination…

Using multi-criteria decision analysis to appraise orphan drugs: a systematic review.

PubMed

Friedmann, Carlotta; Levy, Pierre; Hensel, Paul; Hiligsmann, Mickaël

2018-04-01

Multi-criteria decision analysis (MCDA) could potentially solve current methodological difficulties in the appraisal of orphan drugs. Areas covered: We provide an overview of the existing evidence regarding the use of MCDA in the appraisal of orphan drugs worldwide. Three databases (Pubmed, Embase, Web of Science) were searched for English, French and German literature published between January 2000 and April 2017. Full-text articles were supplemented with conference abstracts. A total of seven articles and six abstracts were identified. Expert commentary: The literature suggests that MCDA is increasingly being used in the context of appraising orphan drugs. It has shown itself to be a flexible approach with the potential to assist in decision-making regarding reimbursement for orphan drugs. However, further research regarding its application must be conducted.

Imagining the future: Community perceptions of a family-based economic empowerment intervention for AIDS-orphaned adolescents in Uganda

PubMed Central

Ismayilova, Leyla; Ssewamala, Fred; Mooers, Elizabeth; Nabunya, Proscovia; Sheshadri, Srividya

2012-01-01

AIDS-orphaned children and adolescents in sub-Saharan Africa have inadequate access to basic services, including health and education. Using a qualitative approach, the study explores the meaning of education in rural Uganda, obstacles faced by AIDS-orphaned adolescents and their caregivers to access secondary education, and the potential of an economic empowerment intervention SEED in addressing the challenges of accessing educational opportunities for AIDS-orphaned adolescents. The findings come from 29 semi-structured interviews conducted with eleven adolescents study participants, four caregivers and fourteen community leaders involved in the pilot SEED intervention. Study participants and community members indicated that the savings accounts offer a unique opportunity for orphaned adolescents to stay in school and imagine the future with optimism. PMID:23543861

eRepo-ORP: Exploring the Opportunity Space to Combat Orphan Diseases with Existing Drugs.

PubMed

Brylinski, Michal; Naderi, Misagh; Govindaraj, Rajiv Gandhi; Lemoine, Jeffrey

2017-12-10

About 7000 rare, or orphan, diseases affect more than 350 million people worldwide. Although these conditions collectively pose significant health care problems, drug companies seldom develop drugs for orphan diseases due to extremely limited individual markets. Consequently, developing new treatments for often life-threatening orphan diseases is primarily contingent on financial incentives from governments, special research grants, and private philanthropy. Computer-aided drug repositioning is a cheaper and faster alternative to traditional drug discovery offering a promising venue for orphan drug research. Here, we present eRepo-ORP, a comprehensive resource constructed by a large-scale repositioning of existing drugs to orphan diseases with a collection of structural bioinformatics tools, including eThread, eFindSite, and eMatchSite. Specifically, a systematic exploration of 320,856 possible links between known drugs in DrugBank and orphan proteins obtained from Orphanet reveals as many as 18,145 candidates for repurposing. In order to illustrate how potential therapeutics for rare diseases can be identified with eRepo-ORP, we discuss the repositioning of a kinase inhibitor for Ras-associated autoimmune leukoproliferative disease. The eRepo-ORP data set is available through the Open Science Framework at https://osf.io/qdjup/. Copyright © 2017. Published by Elsevier Ltd.

Novel Treatments for Rare Cancers: The U.S. Orphan Drug Act Is Delivering-A Cross-Sectional Analysis.

PubMed

Stockklausner, Clemens; Lampert, Anette; Hoffmann, Georg F; Ries, Markus

2016-04-01

Rare cancers are a heterogeneous group of conditions with highly unmet medical needs. Although infrequent in individuals, rare cancers affect millions of people who deserve effective treatments. Therefore, we systematically analyzed the impact of the U.S. Orphan Drug Act of 1983 on delivery of novel treatments for rare cancers. Quantitative cross-sectional analysis was conducted on the U.S. Food and Drug Administration Orphan Drug Product database according to Strengthening the Reporting of Observational Studies in Epidemiology Statement criteria between 1983 and 2015. Since 1983, a total of 177 approvals have originated from 1,391 orphan drug designations to treat rare cancers, which represents 36% of all approvals within the U.S. orphan drug act (n = 492). Two compounds (1%) to treat rare cancer were withdrawn after approval. Median time from designation to approval was 2.49 years (interquartile range 1.13-4.64) and decreased significantly over time (p < .001, linear regression). Over the last decade, rare cancer treatments have been transformed from nonspecific cytotoxic agents toward targeted therapies, such as protein kinase inhibitors and monoclonal antibodies, representing the largest groups of innovative rare cancer treatments today. Most compounds were approved to treat solid tumors and hematological malignancies. The U.S. Orphan Drug Act and associated incentives, such as 7 years of marketing exclusivity, have fostered delivery of novel treatments for rare cancers. More than one-third of all orphan drug approvals address needs of patients suffering from rare cancers. Over the last decade, the understanding of tumorigenesis and genetic driver mutations in different tumor entities has produced innovative treatments, of which many were first approved within the U.S. Orphan Drug Act. Over the last 30 years, the U.S. Orphan Drug Act successfully delivered numerous novel treatments for rare cancers, of which some were subsequently used in other, nonorphan indications. The understanding of molecular mechanisms of diseases is directly connected to the search for novel therapies. The constant pursuit to translate basic research findings into clinical practice is a crucial prerequisite to address unmet medical needs in rare cancers, as in other rare diseases. Oncological drug development proves to be a major player in overall orphan drug research, displayed by more than one-third of all U.S. Food and Drug Administration-approved orphan drugs with oncological indications. ©AlphaMed Press.

A comparative assessment of generalized anxiety, conduct and peer relationship problems among AIDS and other orphaned children in India.

PubMed

Sg, Prem Kumar; G, Anil Kumar; Sp, Ramgopal; V, Venkata Srinivas; Dandona, Rakhi

2016-09-21

Data on mental health among orphaned children in India are scanty. We compared the generalized anxiety, conduct and peer relationship problems and their associated risk factors among children orphaned by HIV/AIDS and those due to other reasons in the Indian city of Hyderabad. Four hundred orphaned children aged 12 to 16 years residing in orphanages in Hyderabad were sampled, half being AIDS orphans (COA) and the rest orphaned due to other reasons (COO). Interviews were done using standardized scales to assess generalized anxiety, conduct and peer relationship problems. A score >8, >4, and >5 was considered as indicator of generalized anxiety, conduct problem and peer relationship problem, respectively. Variations in the intensity of these three conditions due to possible factors including co-existing depression were assessed using multiple classification analysis (MCA). A total of 396 (99.3 %) orphans participated of whom 199 (50.3 %) were COA. The mean generalized anxiety, conduct and peer relationship problem scores were 11.1 (SD 5.2), 3.8 (SD 2.5) and 3.8 (SD 2.5) for COA; and 7.6 (SD 4), 2.6 (SD 2) and 2.3 (SD 1.8) for COO, respectively. Among COA, the prevalence of generalized anxiety score of >8 was 74.4 % (95 % CI 67.8-80.0 %), of conduct problem score of >4 was 33.2 % (95 % CI 26.9-40.1 %), and of peer relationship problem score of >5 was 27.6 %, (95 % CI 21.8-34.3 %), with these being significantly lower in COO. In MCA, a higher mean depression score had the highest effect on the intensity of generalized anxiety, conduct and peer relationship problem (Beta 0.477; 0.379 and 0.453 respectively); being COA and a girl had the most impact on generalized anxiety (0.100 and 0.115, respectively). A significantly high proportion of AIDS orphans deal with generalized anxiety, conduct and peer relationship problem as compared with other orphans highlighting the need to address the poor mental health of orphans in India.

Multi-informant perspective on psychological distress among Ghanaian orphans and vulnerable children within the context of HIV/AIDS.

PubMed

Doku, P N; Minnis, H

2016-08-01

There is little knowledge about the psychosocial distress of children affected by human immunodeficiency virus infection and acquired immune deficiency syndrome (HIV/AIDS) in Ghana, to aid the planning of services. This study investigated mental health problems among children affected by HIV/AIDS, compared with control groups of children orphaned by other causes, and non-orphans. The study employed a cross-sectional survey that interviewed 291 children and their caregivers. Both children and caregivers completed the Strengths and Difficulties Questionnaire that measured children's psychosocial wellbeing. Verbal autopsy was used to identify whether children lost one or both parents from AIDS. The results indicated that controlling for relevant sociodemographic factors, both children's self-reports and caregivers' reports indicate that both children living with HIV/AIDS-infected caregivers and children orphaned by AIDS were at heightened risk for mental health problems than both children orphaned by other causes and non-orphans. The findings further indicated that a significant proportion of orphaned and vulnerable children exhibited symptoms for depression and other psychiatric disorders (approximately 63%) compared with 7% among the non-orphaned group. Caregivers gave higher ratings for children on externalizing problems and lower on internalizing problems, and vice versa when the children's self-reports were analysed. The findings suggest that both children and their informants have diverse yet complementary perspectives on psychological outcomes. The study discusses the theoretical and practical implications of these findings and urgently calls for necessary intervention programmes that target all children affected by HIV/AIDS to effectively alleviate psychological distress and enhance the mental health of these children.

What makes orphans in Kigali, Rwanda, non-adherent to antiretroviral therapy? Perspectives of their caregivers

PubMed Central

Kikuchi, Kimiyo; Poudel, Krishna C; Muganda, John; Sato, Tomoko; Mutabazi, Vincent; Muhayimpundu, Ribakare; Majyambere, Adolphe; Nyonsenga, Simon P; Sase, Eriko; Jimba, Masamine

2014-01-01

Introduction Every year, approximately 260,000 children are infected with HIV in low- and middle-income countries. The timely initiation and high level of maintenance of antiretroviral therapy (ART) are crucial to reducing the suffering of HIV-positive children. We need to develop a better understanding of the background of children's ART non-adherence because it is not well understood. The purpose of this study is to explore the background related to ART non-adherence, specifically in relation to the orphan status of children in Kigali, Rwanda. Methods We conducted 19 focus group discussions with a total of 121 caregivers of HIV-positive children in Kigali. The primary data for analysis were verbatim transcripts and socio-demographic data. A content analysis was performed for qualitative data analysis and interpretation. Results The study found several contextual factors that influenced non-adherence: among double orphans, there was psychological distance between the caregivers and children, whereas economic burden was the primary issue among paternal orphans. The factors promoting adherence also were unique to each orphan status, such as the positive attitude about disclosing serostatus to the child by double orphans’ caregivers, and feelings of guilt about the child's condition among non-orphaned caregivers. Conclusions Knowledge of orphan status is essential to elucidate the factors influencing ART adherence among HIV-positive children. In this qualitative study, we identified the orphan-related contextual factors that influenced ART adherence. Understanding the social context is important in dealing with the challenges to ART adherence among HIV-positive children. PMID:25477050

Relationship Between Family Economic Resources, Psychosocial Well-being, and Educational Preferences of AIDS-Orphaned Children in Southern Uganda: Baseline Findings

PubMed Central

Ssewamala, Fred M.; Nabunya, Proscovia; Ilic, Vilma; Mukasa, Miriam N.; Ddamulira, Christopher

2015-01-01

This study examines the relationship between economic resources, psychosocial well-being, and educational preferences of AIDS-orphaned children in southern Uganda. We use baseline data from a sample of 1410 AIDS-orphaned children (defined as children who have lost one or both biological parents to AIDS) enrolled in the Bridges to the Future study, a National Institute of Child Health and Human Development (NICHD) funded study. Analyses from both bivariate and multiple regression analyses indicate the following: 1) despite the well-documented economic and psychosocial challenges AIDS-orphaned children face, many of these children have high educational plans and aspirations; 2) educational aspirations differ by orphanhood status (double orphan vs. single orphan); 3) regardless of orphanhood status, children report similar levels of psychosocial well-being; 4) high levels of family cohesion, positive perceptions of the future, school satisfaction, and lower levels of hopelessness (hopefulness) are associated with high educational aspirations; and 5) reported family economic resources at baseline, all seem to play a role in predicting children's educational preferences and psychosocial well-being. These findings suggest that the focus for care and support of orphaned children should not be limited to addressing their psychosocial needs. Addressing the economic needs of the households in which orphaned children live is equally important. Indeed, in the context of extreme poverty—in which most of the children represented in this study live—addressing structural factors, including poverty, may be a key driver in addressing their psychosocial functioning. PMID:26146601

Orphan drugs, orphan diseases. The first decade of orphan drug legislation in the EU.

PubMed

Joppi, Roberta; Bertele', Vittorio; Garattini, Silvio

2013-04-01

To assess the methodological quality of Orphan Medicinal Product (OMP) dossiers and discuss possible reasons for the small number of products licensed. Information about orphan drug designation, approval, refusal or withdrawal was obtained from the website of the European Medicines Agency and from the European Public Assessment Reports. From 2000 up to 2010, 80.9 % of the 845 candidate orphan drug designations received a positive opinion from the European Medicines Agency (EMA)'s Committee on Orphan Medicinal Products. Of the 108 OMP marketing authorizations applied for, 63 were granted. Randomised clinical trials were done for 38 OMPs and placebo was used as comparator for nearly half the licensed drugs. One third of the OMPs were tested in trials involving fewer than 100 patients and more than half in trials with 100-200 cases. The clinical trials lasted less than one year for 42.9 % of the approved OMPs. Although there may have been some small improvements over time in the methods for developing OMPs, in our opinion, the number of patients studied, the use of placebo as control, the type of outcome measure and the follow-up have often been inadequate. The present system should be changed to find better ways of fostering the development of effective and sustainable treatments for patients with orphan diseases. Public funds supporting independent clinical research on OMPs could bridge the gap between designation and approval. More stringent criteria to assess OMPs' efficacy and cost/effectiveness would improve the clinical value and the affordability of products allowed onto the market.

77 FR 65709 - Agency Information Collection Activities: Petition To Classify Orphan as an Immediate Relative...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-30

...-0028] Agency Information Collection Activities: Petition To Classify Orphan as an Immediate Relative, Form I-600; Application for Advance Processing of Orphan Petition, Form I-600A; Listing of Adult Member... currently approved collection of information or new collection of information. In accordance with the...

78 FR 5828 - Agency Information Collection Activities: Petition To Classify Orphan as an Immediate Relative...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-28

...-0028] Agency Information Collection Activities: Petition To Classify Orphan as an Immediate Relative, Form I-600; Application for Advance Processing of Orphan Petition, Form I-600A; Listing of Adult Member... be submitting the following information collection request to the Office of Management and Budget...

Anxiety and Autonomy in Adolescence among Father-Orphaned Kibbutz Children.

ERIC Educational Resources Information Center

Kurtz, Chaya; And Others

1993-01-01

Measured anxiety and autonomy in kibbutz father-orphaned (n=28) and nonorphaned (n=42) adolescents. Found no significant differences on levels of manifest anxiety and autonomy. When groups were broken down according to gender and age, found that older father-orphan girls manifested significantly greater anxiety than any group and significantly…

Psychological Characteristics of Adolescents Orphans with Different Experience of Living in a Family

ERIC Educational Resources Information Center

Shulga, Tatyana I.; Savchenko, Daria D.; Filinkova, Evgeniya B.

2016-01-01

The complexity of settling adolescents-orphans in foster families and significant number of break-downs in these families are the problems which determine the relevance of current research. Many adolescent orphans get in social institutions repeatedly, because their psychological features lead to difficulties that their foster parents are unable…

Persisting Mental Health Problems among AIDS-Orphaned Children in South Africa

ERIC Educational Resources Information Center

Cluver, Lucie D.; Orkin, Mark; Gardner, Frances; Boyes, Mark E.

2012-01-01

Background: By 2008, 12 million children in sub-Saharan Africa were orphaned by AIDS. Cross-sectional studies show psychological problems for AIDS-orphaned children, but until now no longitudinal study has explored enduring psychological effects of AIDS-orphanhood in the developing world. Methods: A 4-year longitudinal follow-up of AIDS-orphaned…

21 CFR 316.26 - Amendment to orphan-drug designation.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Amendment to orphan-drug designation. 316.26 Section 316.26 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... designation. (a) At any time prior to approval of a marketing application for a designated orphan drug, the...

Parental HIV/AIDS and Psychosocial Adjustment among Rural Chinese Children

PubMed Central

Fang, Xiaoyi; Stanton, Bonita; Hong, Yan; Zhang, Liying; Zhao, Guoxiang; Zhao, Junfeng; Lin, Xiuyun; Lin, Danhua

2009-01-01

Objective To assess the relationship between parental HIV/AIDS and psychosocial adjustment of children in rural central China. Methods Participants included 296 double AIDS orphans (children who had lost both their parents to AIDS), 459 single orphans (children who had lost one parent to AIDS), 466 vulnerable children who lived with HIV-infected parents, and 404 comparison children who did not experience HIV/AIDS-related illness and death in their families. The measures included depressive symptoms, loneliness, self-esteem, future expectations, hopefulness about the future, and perceived control over the future. Results AIDS orphans and vulnerable children consistently demonstrated poorer psychosocial adjustment than comparison children in the same community. The level of psychosocial adjustment was similar between single orphans and double orphans, but differed by care arrangement among double orphans. Conclusion The findings underscore the urgency and importance of culturally and developmentally appropriate intervention efforts targeting psychosocial problems among children affected by AIDS and call for more exploration of risk and resilience factors, both individual and contextual, affecting the psychosocial wellbeing of these children. PMID:19208701

What is wrong with orphan drug policies?

PubMed

Côté, André; Keating, Bernard

2012-12-01

The effects of orphan drug policies raise serious concerns among payer organizations and lead to often-tragic disappointment for patients who are denied much anticipated drug reimbursements. We evaluate the effects of orphan drug policies on the basis of this concern for real accessibility to drugs. We highlight two unforeseen effects of orphan drug policies: 1) they provide unique business opportunities for manufacturers and 2) drugs approved through these policies are often inaccessible because of their high price. We identify six causes of this emergence of effects. The first four are the direct result of incentives included in orphan drug policies. The fifth cause is the "off-label" use of orphan drugs. These emergent effects have several implications: 1) they raise doubts about the equity of access to drugs, 2) they highlight the limitations of the cohort paradigm in medicine, and c) they force third-party payers to make drugs accessible even when the prices of drugs are believed to be disproportionate to the clinical effects obtained. Copyright © 2012 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Nutrition of orphan marsupials.

PubMed

Stephens, T

1975-10-01

Marsupial milk has been found to be high in fats, protein and ash compared to eutherian milk. The generally low lactose content of marsupial milk and the corresponding low intestinal lactase activity of pouch young marsupials, when considered with the incidence of diarrhoea and the occasional formation of cataracts in orphan kangaroos fed on cow's milk (which has a high lactose content), suggests that a lactose-free milk be fed to orphan marsupials. Of the lactose-free milk substitutes for children now available, it is recommended that Pregestimil, Glucose Nutramigen and particularly CFI be used for very young orphan marsupial herbivores (especially kangaroos), as these are both lactose- and sucrose-free. Isomil, Prosobee and Triglyde, containing sucrose, may be suitable for older kangaroos which are also ingesting solids and brush-tailed possums of all ages. The appropriate natural diet of the orphan marsupial should be available at the time when initial solid food ingestion would occur in the natural state. It is suggested that milk substitute continue to be given until the orphan animal reaches the age where, in the natural state, it would be full independent.

Timing of Orphanhood, Early Sexual Debut, and Early Marriage in Four Sub-Saharan African Countries

PubMed Central

Chae, Sophia

2014-01-01

According to a growing body of literature, some orphans are at heightened risk of early sexual debut and early marriage. This study examines a rarely explored aspect of orphanhood: the timing and type of parental death and their relationship to these outcomes. The study also explores whether education mediates orphans’ risk of early sexual initiation and early marriage. The data are drawn from the 2004 National Survey of Adolescents, which includes interviews with 12–19-year-old adolescents in Burkina Faso, Ghana, Malawi, and Uganda. Results from discrete-time event history analysis indicate that female double orphans, regardless of timing of orphanhood, have greater odds of early sexual debut than do nonorphans. Education explains little of their increased risk. In contrast, male orphans of any type reveal no increased vulnerability to early sexual debut. Uganda is the only country where female orphans, specifically double orphans and those who are paternal orphans before age 10, have greater odds of early marriage, with education accounting for a small portion of the risk. PMID:23719999

Unintended Effects of Orphan Product Designation for Rare Neurological Diseases

PubMed Central

Murphy, Sinéad M; Puwanant, Araya; Griggs, Robert C.

2012-01-01

Since the introduction of the Orphan Drug Act in 1983, designed to promote development of treatments for rare diseases, at least 378 orphan drugs have been approved. Incentives include financial support, tax credits and, perhaps most importantly, extended market exclusivity. These incentives have encouraged industry interest and accelerated research on rare diseases, allowing patients with orphan diseases access to treatments. However, extended market exclusivity has been associated with unacceptably high drug costs; both for newly developed drugs and even for drugs which were previously widely available. We suggest that a paradoxical effect of orphan product exclusivity can be reduced patient access to existing drugs. In addition, the costs of each new drug are arguably unsustainable for patients and for the American health care system. Of all the specialties, neurology has the third highest number of orphan product designations, and neurological diseases account for at least one fifth of rare diseases. Citing the use of tetrabenazine for chorea in Huntington’s disease, adrenocorticotropic hormone for infantile spasms and enzyme replacement therapy with alglucosidase alpha for Pompe’s disease we highlight these paradoxical effects. PMID:23109143

Extended families and perceived caregiver support to AIDS orphans in Rakai district of Uganda

PubMed Central

Karimli, Leyla; Ssewamala, Fred M.; Ismayilova, Leyla

2012-01-01

Purpose To understand the role of extended family in responding to problems of AID-orphaned children and adolescents in Uganda, the study examines who are the primary caregivers of AIDS-orphaned children and adolescents, what are the types of caregiving provided to orphans and whether the quality of caregiving varies by the primary caregiver’s gender and type. Methods The study uses bivariate analyses and mixed effects models utilizing baseline data from a cluster randomized experimental design including 283 orphaned adolescents in Uganda. Results The analysis revealed a generally dominating role of female caregivers for both single and double orphans. In the absence of biological parents – as in the case of double orphans – grandparents’ role as caregivers prevail. On average, the study participants indicated receiving the high level of perceived caregiver support: the average score of 3.56 out of 4 (95% CI=3.5, 3.65). Results of mixed effect models (adjusting for school effects) revealed significant differences in perceived caregiver support by caregiver’s gender. Compared to their male counterparts, female participants with whom the child/adolescent lives (B=0.22, 95% CI=0.11, 0.34) and women who are currently taking care of a child/adolescent (B=0.15, 95% CI=0.05, 0.26) provide greater caregiver support as perceived and reported by a child/adolescent. Similarly, female financiers – compared to male source of financial support - provide greater caregiver support as perceived and reported by a child/adolescent (B=0.16, 95% CI=0.04, 0.3). Conclusions Our findings demonstrate that extended families are still holding up as an important source of care and support for AIDS orphaned children and adolescents in Uganda. The findings support the argument about importance of matrilineal and grandparental care for AIDS orphans. PMID:23188930

Bioinformatics in the orphan crops.

PubMed

Armstead, Ian; Huang, Lin; Ravagnani, Adriana; Robson, Paul; Ougham, Helen

2009-11-01

Orphan crops are those which are grown as food, animal feed or other crops of some importance in agriculture, but which have not yet received the investment of research effort or funding required to develop significant public bioinformatics resources. Where an orphan crop is related to a well-characterised model plant species, comparative genomics and bioinformatics can often, though not always, be exploited to assist research and crop improvement. This review addresses some challenges and opportunities presented by bioinformatics in the orphan crops, using three examples: forage grasses from the genera Lolium and Festuca, forage legumes and the second generation energy crop Miscanthus.

Flexible kinship: caring for AIDS orphans in rural Lesotho

PubMed Central

Block, Ellen

2015-01-01

HIV/AIDS has devastated families in rural Lesotho, leaving many children orphaned. Families have adapted to the increase in the number of orphans and HIV-positive children in ways that provide children with the best possible care. Though local ideas about kinship and care are firmly rooted in patrilineal social organization, in practice, maternal caregivers, often grandmothers, are increasingly caring for orphaned children. Negotiations between affinal kin capitalize on flexible kinship practices in order to legitimate new patterns of care, which have shifted towards a model that often favours matrilocal practices of care in the context of idealized patrilineality. PMID:25866467

Multiple transitions and HIV risk among orphaned Kenyan schoolgirls.

PubMed

Mojola, Sanyu A

2011-03-01

Why are orphaned girls at particular risk of acquiring HIV infection? Using a transition-to-adulthood framework, this study employs qualitative data from Nyanza Province, Kenya, to explore pathways to HIV risk among orphaned and nonorphaned high-school girls. It shows how simultaneous processes such as leaving their parental home, negotiating financial access, and relationship transitions interact to produce disproportionate risk for orphaned girls. The role of financial provision and parental love in modifying girls' trajectories to risk are also explored. A testable theoretical model is proposed based on the qualitative findings, and policy implications are suggested.

MULTIPLE TRANSITIONS AND HIV RISK AMONG AFRICAN SCHOOL GIRLS

PubMed Central

Mojola, Sanyu A

2012-01-01

Why are orphaned girls at particular risk of contracting HIV? Using a transition to adulthood framework, this paper uses qualitative data from Nyanza province, Kenya to explore pathways to HIV risk among orphaned and non-orphaned high school girls. I show how co-occurring processes such as residential transition out of the parental home, negotiating financial access and relationship transitions interact to produce disproportionate risk for orphan girls. I also explore the role of financial provision and parental love in modifying girls’ trajectories to risk. I propose a testable theoretical model based on the qualitative findings and suggest policy implications. PMID:21500699

The current status of orphan drug development in Europe and the US.

PubMed

Hall, Anthony K; Carlson, Marilyn R

2014-02-01

Orphan drug legislation has been introduced in a number of countries in order to stimulate the development of treatments for rare diseases by introducing commercial incentives for companies wishing to undertake that development. In order to navigate the maze of regulatory regulations and procedures so that companies can make proper use of the orphan drug incentives, specialist knowledge is required. This article will review the current status of orphan drug development in the EU and the US, explain the incentives and procedures, and touch on the role of patient organisations in the process.

The histone demethylase Jarid1b ensures faithful mouse development by protecting developmental genes from aberrant H3K4me3.

PubMed

Albert, Mareike; Schmitz, Sandra U; Kooistra, Susanne M; Malatesta, Martina; Morales Torres, Cristina; Rekling, Jens C; Johansen, Jens V; Abarrategui, Iratxe; Helin, Kristian

2013-04-01

Embryonic development is tightly regulated by transcription factors and chromatin-associated proteins. H3K4me3 is associated with active transcription and H3K27me3 with gene repression, while the combination of both keeps genes required for development in a plastic state. Here we show that deletion of the H3K4me2/3 histone demethylase Jarid1b (Kdm5b/Plu1) results in major neonatal lethality due to respiratory failure. Jarid1b knockout embryos have several neural defects including disorganized cranial nerves, defects in eye development, and increased incidences of exencephaly. Moreover, in line with an overlap of Jarid1b and Polycomb target genes, Jarid1b knockout embryos display homeotic skeletal transformations typical for Polycomb mutants, supporting a functional interplay between Polycomb proteins and Jarid1b. To understand how Jarid1b regulates mouse development, we performed a genome-wide analysis of histone modifications, which demonstrated that normally inactive genes encoding developmental regulators acquire aberrant H3K4me3 during early embryogenesis in Jarid1b knockout embryos. H3K4me3 accumulates as embryonic development proceeds, leading to increased expression of neural master regulators like Pax6 and Otx2 in Jarid1b knockout brains. Taken together, these results suggest that Jarid1b regulates mouse development by protecting developmental genes from inappropriate acquisition of active histone modifications.

Quantification and in situ localisation of abcb1 and abcc9genes in toxicant-exposed sea urchin embryos.

PubMed

Bošnjak, Ivana; Pleić, Ivana Lepen; Borra, Marco; Mladineo, Ivona

2013-12-01

A multixenobiotic resistance (MXR) mechanism mediated by ABC binding cassette (ABC) transport proteins is an efficient chemical defence mechanism in sea urchin embryos. The aim of our work was to evidence whether exposure to sub-lethal doses of specific contaminants (oxybenzone (OXI), mercuric chloride (HgCl2) and trybutiltin (TBT)) would induce MXR transporter activity during embryonic development (from zygote to blastula stage) in purple sea urchin (Paracentrotus lividus) embryos. Further, we present data on molecular identification, transport function, expression levels and gene localisation of two ABC efflux transporters-P-glycoprotein (ABCB1/P-gp) and sulfonylurea-receptor-like protein (ABCC9/SUR-like). Partial cDNA sequences of abcb1 and abcc9 were identified and quantitative PCR (qPCR) evidenced an increase in mRNA transcript levels of both ABC transporters during the two-cell, as well as an overall decrease during the blastulae stage. Calcein-AM efflux activity assay indicated the activation of multidrug resistance-associated protein/ABCC-like transport in the presence of HgCl2 and TBT in exposed blastulae. The in situ hybridisation of the two-cell and blastula stages showed ubiquitous localisation of both transcripts within cells, supporting qPCR data. In conclusion, ABCB1 and ABCC9 are constitutive, as are HgCl2, TBT and OXI-inducible ABC membrane transporters, coexpressed in the zygote, two-cell and blastula stages of the P. lividus. Their ubiquitous cell localisation further fortifies their protective role in early embryonic development.

The Histone Demethylase Jarid1b Ensures Faithful Mouse Development by Protecting Developmental Genes from Aberrant H3K4me3

PubMed Central

Kooistra, Susanne M.; Malatesta, Martina; Morales Torres, Cristina; Rekling, Jens C.; Johansen, Jens V.; Abarrategui, Iratxe; Helin, Kristian

2013-01-01

Embryonic development is tightly regulated by transcription factors and chromatin-associated proteins. H3K4me3 is associated with active transcription and H3K27me3 with gene repression, while the combination of both keeps genes required for development in a plastic state. Here we show that deletion of the H3K4me2/3 histone demethylase Jarid1b (Kdm5b/Plu1) results in major neonatal lethality due to respiratory failure. Jarid1b knockout embryos have several neural defects including disorganized cranial nerves, defects in eye development, and increased incidences of exencephaly. Moreover, in line with an overlap of Jarid1b and Polycomb target genes, Jarid1b knockout embryos display homeotic skeletal transformations typical for Polycomb mutants, supporting a functional interplay between Polycomb proteins and Jarid1b. To understand how Jarid1b regulates mouse development, we performed a genome-wide analysis of histone modifications, which demonstrated that normally inactive genes encoding developmental regulators acquire aberrant H3K4me3 during early embryogenesis in Jarid1b knockout embryos. H3K4me3 accumulates as embryonic development proceeds, leading to increased expression of neural master regulators like Pax6 and Otx2 in Jarid1b knockout brains. Taken together, these results suggest that Jarid1b regulates mouse development by protecting developmental genes from inappropriate acquisition of active histone modifications. PMID:23637629

Expression of phosphatidylcholine biosynthetic enzymes during early embryogenesis in the amphibian Bufo arenarum.

PubMed

Fernández-Bussy, Rodrigo; Mouguelar, Valeria; Banchio, Claudia; Coux, Gabriela

2015-04-01

In the principal route of phosphatidylcholine (PC) synthesis the regulatory steps are catalysed by CTP:phosphocholine cytidylyltransferase (CCT) and choline kinase (CK). Knock-out mice in Pcyt1a (CCT gene) and Chka1 (CK gene) resulted in preimplantation embryonic lethality, demonstrating the essential role of this pathway. However, there is still a lack of detailed CCT and CK expression analysis during development. The aim of the current work was to study the expression during early development of both enzymes in the external-fertilization vertebrate Bufo arenarum. Reverse transcription polymerase chain reaction (RT-PCR) and western blot confirmed their presence in unfertilized eggs. Analysis performed in total extracts from staged embryos showed constant protein levels of both enzymes until the 32-cell stage: then they decreased, reaching a minimum in the gastrula before starting to recover. CTP:phosphocholine cytidylyltransferase is an amphitropic enzyme that inter-converts between cytosolic inactive and membrane-bound active forms. Immunoblot analysis demonstrated that the cytosolic:total CCT protein ratio does not change throughout embryogenesis, suggesting a progressive decline of CCT activity in early development. However, PC (and phosphatidylethanolamine) content per egg/embryo remained constant throughout the stages analysed. In conclusion, the current data for B. arenarum suggest that net synthesis of PC mediated by CCT and CK is not required in early development and that supplies for membrane biosynthesis are fulfilled by lipids already present in the egg/embryo reservoirs.

Effects of the herbicides linuron and S-metolachlor on Perez's frog embryos.

PubMed

Quintaneiro, Carla; Soares, Amadeu M V M; Monteiro, Marta S

2018-03-01

Presence of pesticides in the environment and their possible effects on aquatic organisms are of great concern worldwide. The extensive use of herbicides in agricultural areas are one of the factors contributing to the known decline of amphibian populations. Thus, as non-target species, amphibians can be exposed in early life stages to herbicides in aquatic systems. In this context, this study aims to evaluate effects of increasing concentrations of two maize herbicides, linuron and S-metolachlor on embryos of the Perez' frog (Pelophylax perezi) during 192 h. Apical endpoints were determined for each herbicide: mortality, hatching rate, malformations and length. Frog embryos presented a LC 50 of 21 mg/l linuron and 37.5 mg/l S-metolachlor. Furthermore, sub-lethal concentrations of both herbicides affected normal embryonic development, delaying hatching, decreasing larvae length and causing several malformations. Length of larvae decreased with increasing concentrations of each herbicide, even at the lower concentrations tested. Malformations observed in larvae exposed to both herbicides were oedemas, spinal curvature and deformation, blistering and microphtalmia. Overall, these results highlight the need to assess adverse effects of xenobiotics to early life stages of amphibians regarding beside mortality the embryonic development, which could result in impairments at later stages. However, to unravel mechanisms involved in toxicity of these herbicides further studies regarding lower levels of biological organisation such as biochemical and genomic level should be performed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lethal and sublethal effects of embryonic and larval exposure of Hyla versicolor to Stormwater pond sediments.

PubMed

Brand, Adrianne B; Snodgrass, Joel W; Gallagher, Matthew T; Casey, Ryan E; Van Meter, Robin

2010-02-01

Stormwater ponds are common features of modern stormwater management practices. Stormwater ponds often retain standing water for extended periods of time, develop vegetative characteristics similar to natural wetlands, and attract wildlife. However, because stormwater ponds are designed to capture pollutants, wildlife that utilize ponds might be exposed to pollutants and suffer toxicological effects. To investigate the toxicity of stormwater pond sediments to Hyla versicolor, an anuran commonly found using retention ponds for breeding, we exposed embryos and larvae to sediments in laboratory microcosms. Exposure to pond sediments reduced survival of embryos by approximately 50% but did not affect larval survival. Larvae exposed to stormwater pond sediment developed significantly faster (x = 39 days compared to 42 days; p = 0.005) and were significantly larger at metamorphosis (x = 0.49 g compared to 0.36 g; p < 0.001) than controls that were exposed to clean sand. Substantial amounts (712-2215 mg/l) of chloride leached from pond sediments into the water column of treatment microcosms; subsequently, survival of embryos was negatively correlated (r (2) = 0.50; p < 0.001) with water conductivity during development. Our results, along with the limited number of other toxicological studies of stormwater ponds, suggest that road salt contributes to the degradation of stormwater pond habitat quality for amphibian reproduction and that future research should focus on understanding interactions among road salts and other pollutants and stressors characteristic of urban environments.

Ecotoxicological bioassays of sediment leachates in a river bed flanked by decommissioned pesticide plants in Nantong City, East China.

PubMed

Zhou, Yan; Wang, Fenghe; Wan, Jinzhong; He, Jian; Li, Qun; Qiang Chen; Gao, Jay; Lin, Yusuo; Zhang, Shengtian

2017-03-01

Traditionally, the toxicity of river contaminants is analyzed chemically or physically through river bed sediments. The biotoxicity of polluted sediment leachates has not caught our attention. This study aims to overcome this deficiency through a battery of biotests which were conducted to monitor comprehensive toxicity of sediment leachates for the Yaogang River in East Jiangsu Province of China, which is in close proximity to former pesticide plants. The general physical and chemical parameters of major pollutants were analyzed from river bed sediments collected at five strategic locations. The ecotoxicity analyses undertaken include overall fish (adult zebrafish) acute toxicity, luminescent bacteria (Vibrio fischeri) bioassay, and zebrafish embryo toxicity assay. Compared with the control group, sediment leachates increased the lethality, inhibited the embryos hatching and induced development abnormalities of zebrafish embryos, and inhibited the luminescence of V. fischeri. The results show that sediment leachates may assume various toxic effects, depending on the test organism. This diverse toxicity to aquatic organisms reflects their different sensitivity to sediment leachates. It is found clearly that V. fischeri was the organism which was characterized by the highest sensitivity to the sediment leachates. The complicated toxicity of leachates was not caused by one single factor but by multiple pollutants together. This indicates the need of estimations of sediment leachate not only taking into account chemical detection but also of applying the biotests to the problem. Thus, multigroup bioassays are necessary to realistically evaluate river ecological risks imposed by leachates.

Zebrafish numb and numblike are involved in primitive erythrocyte differentiation.

PubMed

Bresciani, Erica; Confalonieri, Stefano; Cermenati, Solei; Cimbro, Simona; Foglia, Efrem; Beltrame, Monica; Di Fiore, Pier Paolo; Cotelli, Franco

2010-12-13

Notch signaling is an evolutionarily conserved regulatory circuitry implicated in cell fate determination in various developmental processes including hematopoietic stem cell self-renewal and differentiation of blood lineages. Known endogenous inhibitors of Notch activity are Numb-Nb and Numblike-Nbl, which play partially redundant functions in specifying and maintaining neuronal differentiation. Nb and Nbl are expressed in most tissues including embryonic and adult hematopoietic tissues in mice and humans, suggesting possible roles for these proteins in hematopoiesis. We employed zebrafish to investigate the possible functional role of Numb and Numblike during hematopoiesis, as this system allows a detailed analysis even in embryos with severe defects that would be lethal in other organisms. Here we describe that nb/nbl knockdown results in severe reduction or absence of embryonic erythrocytes in zebrafish. Interestingly, nb/nbl knocked-down embryos present severe downregulation of the erythroid transcription factor gata1. This results in erythroblasts which fail to mature and undergo apoptosis. Our results indicate that Notch activity is increased in embryos injected with nb/nbl morpholino, and we show that inhibition of Notch activation can partially rescue the hematopoietic phenotype. Our results provide the first in vivo evidence of an involvement of Numb and Numblike in zebrafish erythroid differentiation during primitive hematopoiesis. Furthermore, we found that, at least in part, the nb/nbl morphant phenotype is due to enhanced Notch activation within hematopoietic districts, which in turn results in primitive erythroid differentiation defects.

Developing a list of reference chemicals for testing alternatives to whole fish toxicity tests.

PubMed

Schirmer, Kristin; Tanneberger, Katrin; Kramer, Nynke I; Völker, Doris; Scholz, Stefan; Hafner, Christoph; Lee, Lucy E J; Bols, Niels C; Hermens, Joop L M

2008-11-11

This paper details the derivation of a list of 60 reference chemicals for the development of alternatives to animal testing in ecotoxicology with a particular focus on fish. The chemicals were selected as a prerequisite to gather mechanistic information on the performance of alternative testing systems, namely vertebrate cell lines and fish embryos, in comparison to the fish acute lethality test. To avoid the need for additional experiments with fish, the U.S. EPA fathead minnow database was consulted as reference for whole organism responses. This database was compared to the Halle Registry of Cytotoxicity and a collation of data by the German EPA (UBA) on acute toxicity data derived from zebrafish embryos. Chemicals that were present in the fathead minnow database and in at least one of the other two databases were subject to selection. Criteria included the coverage of a wide range of toxicity and physico-chemical parameters as well as the determination of outliers of the in vivo/in vitro correlations. While the reference list of chemicals now guides our research for improving cell line and fish embryo assays to make them widely applicable, the list could be of benefit to search for alternatives in ecotoxicology in general. One example would be the use of this list to validate structure-activity prediction models, which in turn would benefit from a continuous extension of this list with regard to physico-chemical and toxicological data.

Who wants to adopt and who wants to be adopted: a sample of American families and sub-Saharan African orphans.

PubMed

Balding, Christopher; Feng, Yan; Atashband, Armita

2015-12-01

The debate between pro- and anti-international adoption advocates relies heavily on rhetoric and little on data analysis. To better understand the state of orphans and potential adopters in this debate, we utilize the National Survey of Family Growth (NSFG) and the Demographic and Health Surveys (DHS) to study who adopts internationally and the status of orphaned children in sub-Saharan Africa. According to NSFG data adopters are church going, highly educated, stable families aware of the challenges faced by international adoption, with high rates of infertility and rates of child abuse half the population average. According to the DHS data, orphans in sub-Saharan Africa suffer from significantly higher deprivation, reduced schooling and increased levels of stunting and underweight reported than their cohort. Using this data, we estimate conservatively that that 1 50 000 orphans from our sample of sub-Saharan African countries died from their 5-year birth cohort. Given the large number of families seeking to adopt and the high number of orphan deaths, it seems counterproductive to restrict international adoptions given the significantly lower risks faced by children in adopted families compared with remaining orphaned. © The Author 2015; all rights reserved. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine.

Policies and availability of orphan medicines in outpatient care in 24 European countries.

PubMed

Sarnola, Kati; Ahonen, Riitta; Martikainen, Jaana E; Timonen, Johanna

2018-04-09

To assess pricing and reimbursement policies specific to orphan medicines and the availability and distribution settings of ten recently authorised medicinal products suitable for outpatient care with orphan status and centralised marketing authorisation in Europe, and whether patients receive these products free of charge or have to pay some or all of the costs themselves. Web survey to authorities and representatives of third party payers in the Pharmaceutical Pricing and Reimbursement Information (PPRI) network in April 2016. In most of the 24 countries, special policies were not implemented in the assessment of reimbursement status (22 countries) or in the pricing (20 countries) of orphan medicines. An average of five of the ten recently authorised products per country were available for outpatient care. Products were dispensed from community pharmacies in eight countries and from health care units in five countries. In four countries, both distribution settings were used. When products were dispensed from community pharmacies, patients typically paid some of the price themselves. Products dispensed from health care units were often free of charge for patients. Most European countries had not implemented pricing and reimbursement policies specific to orphan medicines. The availability of orphan products varied between countries. It is important to discuss whether orphan medicines should be considered as a separate group in the reimbursement regulations in order to secure patient access to these medicines.

[Orphan drugs: some legal, ethical and economics aspects].

PubMed

Pabst, J Y

2001-09-01

Besides well-known diseases, about 5,000 identified are classed as "orphan" because of the lack of any response in terms of diagnosis, prevention and treatment. The development of drugs for these diseases, intended for a limited number of patients, often requires considerable research, and subsequently, cost. The aim of the present article is to discuss the ethical, political and economic problems relevant to the development and disposal of drugs specifically designed for these diseases, now commonly called "orphan" drugs. These questions have been raised at discussions and dialogues at the European Parliament where European regulations on orphan drugs were adopted on December 15, 1999. These regulations (141/2000/EEC) came into effect in the European Union on January 22, 2000, and are widely inspired from the American model. The regulations stipulate that the criterion for designation of the drug is based on a disease prevalence of 5/10000). Advantages commonly recognized for the orphan drug status concern: community registration (centralized marketing approval), eligibility for grants and national or community fiscal support, lower or canceled registration fees, technical contribution via the European drug agency (EMEA), and exclusive rights for a 10-year period. On May 12, 2000, the European Commission completed the status by adopting rules establishing the criteria used for designating a drug as an orphan drug. This document implements the dispositions available to pharmaceutical firms inciting them to invest in the development of orphan drugs.

Growth status of Korean orphans raised in the affluent West: anthropometric trend, multivariate determinants, and descriptive comparison with their North and South Korean peers.

PubMed

Schwekendiek, Daniel J

2017-04-01

This paper investigates the trend in height among adult Korean orphans who were adopted in early life into affluent Western nations. Final heights of 148 females were analyzed based on a Korean government survey conducted in 2008. Height of the orphans was descriptively compared against final heights of South and North Koreans. Furthermore, statistical determinants of orphan height were investigated in multivariate regressions. Mean height of Korean orphans was 160.44 cm (SD 5.89), which was higher than that of South Koreans at 158.83 cm (SD 5.01). Both Korean orphans and South Koreans were taller than North Koreans at 155.30 cm (SD 4.94). However, height of Korean orphans stagnated at around 160-161 cm while those of North and South Koreans improved over time. In the regression analysis, the socioeconomic status of the adoptive family was statistically significant in all models, while dummies for the adoptive nations and age at adoption were insignificant. This study shows that the mean final height of women experiencing extreme environmental improvements in early-life is capped at 160-161 cm, tentatively suggesting that social stress factors in the host nation or early-life factors in the birth nation might have offset some of the environmental enrichment effects achieved through intercountry adoption.

21 CFR 316.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-04-01

... Health Service Act (42 U.S.C. 262). (10) Orphan drug means a drug intended for use in a rare disease or... already been approved for the same use or indication. (13) Orphan subset of a non-rare disease or condition (“orphan subset”) means that use of the drug in a subset of persons with a non-rare disease or...

Orphan Children: Adjusting to Life after the Boarding Institution

ERIC Educational Resources Information Center

Prisiazhnaia, N. V.

2008-01-01

According to official statistics, in Russia there are over 800,000 orphans and children who are deprived of parental care; 260,000 are living and being taught in more than 4,000 state boarding institutions. The category "orphan child" consists of children up to the age of eighteen, one or both of whose parents have died. The term…

77 FR 52744 - Food and Drug Administration/European Medicines Agency Orphan Product Designation and Grant Workshop

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-30

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2012-N-0001] Food and Drug Administration/European Medicines Agency Orphan Product Designation and Grant Workshop AGENCY: Food and Drug Administration, HHS. ACTION: Notice of meeting. The Food and Drug Administration's (FDA) Office of Orphan Products Development...

FDA grants orphan drug status to selumetinib for neurofibromatosis type 1 (NF1) treatment | Center for Cancer Research

Cancer.gov

The U.S. Food and Drug Administration granted orphan drug status in February to selumetinib for use in patients with the genetic disorder neurofibromatosis type 1 (NF1), who often develop tumors of the peripheral nervous system. Receiving orphan drug designation is a helpful step for selumetinib.

Risk and Resilience in Orphaned Adolescents Living in a Community Affected by AIDS

ERIC Educational Resources Information Center

Wild, Lauren G.; Flisher, Alan J.; Robertson, Brian A.

2013-01-01

The AIDS pandemic has resulted in a dramatic rise in the number of orphans in South Africa. This study was designed to investigate the associations between family, peer, and community factors and resilience in orphaned adolescents. Self-report questionnaires were administered verbally to 159 parentally bereaved adolescents (aged 10-19) in an…

Psychosocial Support for Children Orphaned by HIV/AIDS in Zimbabwe

ERIC Educational Resources Information Center

Chitiyo, Jonathan; Chitiyo, Argnue; Chitiyo, Morgan

2016-01-01

Healthy psychosocial development during childhood is a key determinant to the future well-being of all individuals. In many areas of Africa, demand for psychosocial support continues to grow in response to the increasing number of children left orphaned as a result of the HIV/AIDS pandemic. These orphans face various challenges and yet, in most…

Social Support Disparities for Caregivers of AIDS-Orphaned Children in South Africa

ERIC Educational Resources Information Center

Kuo, Caroline; Fitzgerald, Jane; Operario, Don; Casale, Marisa

2012-01-01

Drawing upon a sample of 1,599 adults caring for children in HIV-endemic Umlazi Township in South Africa, this cross-sectional survey investigated whether perceived social support varied among caregivers of AIDS-orphaned children (n = 359) as compared with caregivers of children orphaned by other causes (n = 171) and caregivers of nonorphaned…

The Varying Vulnerability of African Orphans: The Case of the Langi, Northern Uganda

ERIC Educational Resources Information Center

Oleke, Christopher; Blystad, Astrid; Moland, Karen Marie; Rekdal, Ole Bjorn; Heggenhougen, Kristian

2006-01-01

This article is based on a qualitative study carried out in Lira District, northern Uganda, to assess the situation of orphans cared for in extended families. The objective of the article is to bring attention to the varying vulnerability of different categories of orphans. The methods employed in data collection included ethnographic fieldwork,…

75 FR 65499 - Agency Information Collection Activities: Form I-600/I-600A, Extension of a Currently Approved...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-25

... Classify Orphan as an Immediate Relative and Application for Advance Processing of Orphan Petition; OMB... encouraged and will be accepted until November 24, 2010. This process is conducted in accordance with 5 CFR...) Title of the Form/Collection: Petition to Classify Orphan as an Immediate Relative and Application for...

“The Luggage that isn’t Theirs is Too Heavy…”:Understandings of Orphan Disadvantage in Lesotho

PubMed Central

Goldberg, Rachel E.; Short, Susan E.

2012-01-01

In Southern Africa, high adult HIV prevalence has fueled concern about the welfare of children losing parents to the epidemic. A growing body of evidence indicates that parental, particularly maternal, death is negatively associated with child outcomes. However, a better understanding of the mechanisms is needed. In addition, the way orphan disadvantage and the mechanisms giving rise to it are understood on the ground is essential for the successful translation of research into policies and programs. This study employs data from 89 in-depth interviews with caregivers and key informants in Lesotho, a setting where approximately one-quarter of adults is infected with HIV, to elaborate understandings of orphan disadvantage. Our analysis focuses on two questions: (i) Do local actors perceive orphans to be disadvantaged compared to non-orphans, and if so, in what ways; and (ii) How do they explain orphans’ differential disadvantage? Analyses suggest that orphans were widely perceived to be disadvantaged; respondents described this disadvantage in material as well as affective domains. Thematic analyses reveal five broad categories of explanation: poverty, love and kin connection, caregiver character, perceptions of orphans, and community norms related to orphan care. These results underscore the need for research and policy to address (i) multiple types of disadvantage, including deficits in kindness and attention; and (ii) the social embeddedness of disadvantage, recognizing that poverty, kinship, and community interact with individual attributes to shape caregiving relationships and child experiences. The findings suggest limited success for programs and policies that do not address the emotional needs of children, or that focus on child or caregiver support to the exclusion of community outreach. PMID:22865946

Gallbladder cancer: review of a rare orphan gastrointestinal cancer with a focus on populations of New Mexico.

PubMed

Nemunaitis, Jacklyn M; Brown-Glabeman, Ursa; Soares, Heloisa; Belmonte, Jessica; Liem, Ben; Nir, Itzhak; Phuoc, Victor; Gullapalli, Rama R

2018-06-18

Gallbladder cancer is a rare malignancy of the biliary tract with a poor prognosis, frequently presenting at an advanced stage. While rare in the United States overall, gallbladder cancer has an elevated incidence in geographically distinct locations of the globe including Chile, North India, Korea, Japan and the state of New Mexico in the United States. People with Native American ancestry have a much elevated incidence of gallbladder cancer compared to Hispanic and non-Hispanic white populations of New Mexico. Gallbladder cancer is also one of the few bi-gendered cancers with an elevated female incidence compared to men. Similar to other gastrointestinal cancers, gallbladder cancer etiology is likely multi-factorial involving a combination of genomic, immunological, and environmental factors. Understanding the interplay of these unique epidemiological factors is crucial in improving the prevention, early detection, and treatment of this lethal disease. Previous studies have failed to identify a distinct genomic mutational profile in gallbladder cancers, however, work to identify promising clinically actionable targets is this form of cancer is ongoing. Examples include, interest in the HER2/Neu signaling pathway and the recognition that chronic inflammation plays a crucial role in gallbladder cancer pathogenesis. In this review, we provide a comprehensive overview of gallbladder cancer epidemiology, risk factors, pathogenesis, and treatment with a specific focus on the rural and Native American populations of New Mexico. We conclude this review by discussing future research directions with the goal of improving clinical outcomes for patients of this lethal malignancy.

Knowing Kids Dying of HIV: A Traumatic Event for AIDS Orphans

PubMed Central

Zhao, Qun; Li, Xiaoming; Lin, Xiuyun; Fang, Xiaoyi; Zhao, Guoxiang; Zhao, Junfeng

2009-01-01

Data from 755 AIDS orphans living in a rural area of China with high rates of HIV infection were used to examine the association between a child’s trauma symptoms and knowing a peer with HIV infection or one who had died of HIV. Trauma symptoms were measured by the Traumatic Symptoms Checklist for Children-Chinese Version (TSCC-CV). About 47% of participants reported they knew a child with HIV or one who had died of HIV. More orphans living in family-based care reported such knowledge, and trauma symptoms were significantly higher in children who reported such knowledge. Multivariate analysis revealed that such knowledge was significantly associated with traumatic symptoms, controlling for gender, age, family socioeconomic status, orphan status (double vs. single), and care arrangement (family-based vs. institutional care). The findings underscored the importance of psychosocial support and counseling to orphans in communities with high levels of HIV-related mortality. PMID:19576544

Analysis of chorioallantoic membranes to assess PCB accumulation in American alligators and Loggerhead sea turtles from the coast of South Carolina

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cobb, G.P.; Wood, P.D.; O`Quinn, M.

1995-12-31

Investigation of contaminant burdens in threatened and endangered species is difficult due to the small number of samples that can be collected. Many samples can be collected if the sampling methods are non-lethal and more specifically non-invasive. Analysis of chorioallantoic membranes is demonstrated for American alligators and Loggerhead sea turtles. Significant differences were found in PCB, uptake by alligators from the Ashepoo-Combahee-Edisto Basin reference site and a contaminated site in Winyah Bay. Intrasite and intersite differences in uptake and distribution of PCB homologues were noted. These data will be discussed as they relate to egg viability and embryo development.