50 research outputs found
Psychiatric Morbidity (Depression And Anxiety) In Children With Some Dermatological Diseases At Derna, Libya.
No full textBackground: Whenever children are sick there is a psychological component to the illness.
Objectives: to assess depression and anxiety in children with some skin diseases.
Methodology: This study included 100 children with ages ranged from 6 to 14 years. They were divided into 50 apparently healthy children (used as a control group) and 50 patients
(children suffering from psoriasis, acne, urticaria, atopic dermatitis and alopecia), attended the dermatology outpatient clinic at Al Wahda Hospital and Community Health Center, Dema,
Libya, from I st Jan. 2006 to May 30,2006. For all children the following were done: full medical history and clinical examination, D-test for depression for children and anxiety
manifest scale for children.
Results: There was a significant difference between the mean scores of anxiety in skin disease children (19.9 ± 6.4) and the healthy control (13.2 ± 5.6,
The generation of live offspring from vitrified oocytes
No full textOocyte cryopreservation is extremely beneficial for assisted reproductive technologies, the treatment of infertility and biotechnology and offers a viable alternative to embryo freezing and ovarian grafting approaches for the generation of embryonic stem cells and live offspring. It also offers the potential to store oocytes to rescue endangered species by somatic cell nuclear transfer and for the generation of embryonic stem cells to study development in these species. We vitrified mouse oocytes using a range of concentrations of trehalose (0 to 0.3 M) and demonstrated that 0.1 and 0.3 M trehalose had similar developmental rates, which were significantly different to the 0.2 M cohort (P < 0.05). As mitochondria are important for fertilisation outcome, we observed that the clustering and distribution of mitochondria of the 0.2 M cohort were more affected by vitifrication than the other groups. Nevertheless, all 3 cohorts were able to develop to blastocyst, following in vitro fertilisation, although developmental rates were better for the 0.1 and 0.3 M cohorts than the 0.2 M cohort (P < 0.05). Whilst blastocysts gave rise to embryonic stem-like cells, it was apparent from immunocytochemistry and RT-PCR that these cells did not demonstrate true pluripotency and exhibited abnormal karyotypes. However, they gave rise to teratomas following injection into SCID mice and differentiated into cells of each of the germinal layers following in vitro differentiation. The transfer of 2-cell embryos from the 0.1 and 0.3 M cohorts resulted in the birth of live offspring that had normal karyotypes (9/10). When 2-cell embryos from vitrified oocytes underwent vitrification, and were thawed and transferred, live offspring were obtained that exhibited normal karyotypes, with the exception of one offspring who was larger and died at 7 months. We conclude that these studies highlight the importance of the endometrial environment for the maintenance of genetic stability and thus the propagation of specific genetic traits
Biochemical and insecticidal efficacy of clove and basil essential oils and two photosensitizers and their combinations on Aphis gossypii glover (Hemiptera: Aphididae)
No full textThe present study investigates the insecticidal and biochemical effects of two essential oils (EOs) and two photosensitizers against cotton aphids in a laboratory setting. The EOs evaluated were clove (Syzygium aromaticum L.) and basil (Ocimum basilicum), while the photosensitizers were rose bengal and rhodamine B. The individual median lethal concentrations (LC50) revealed that clove was ~4.44 times more potent than basil, and rhodamine B was ~1.34 times more potent than rose bengal. The mortality rates increased using higher concentrations of the photosensitizers and prolonging exposure time to sunlight. The most effective combination against adult aphids was found to be a mixture of sub-lethal concentrations of clove and rhodamine B, resulting in a mortality rate of 92.31%. Conversely, the combination of basil and rose bengal exhibited the lowest efficacy with a mortality rate of 33.33%. Biochemical analyses indicate that Rhodamine B, basil, and the basil-rhodamine B mixture (mixture C) significantly reduced trehalase activity. However, the protease activity significantly increased in aphids treated with rose bengal, clove, and the clove-rose bengal mixtures (mixtures A and B). The lipase activity is notably decreased upon treatment with rhodamine B and clove. Glutathione S-transferase (GST) activity decreased in aphids treated with rose bengal and the basil-rhodamine B mixtures (mixtures C and D), suggesting that GST did not play a role in detoxifying these compounds, thereby explaining the susceptibility of A. gossypii. Overall, the combination of essential oils and photosensitizers has demonstrated a synergistic effect in controlling Aphis gossypii, offering great potential as an effective strategy for aphid management
Mecanismes fisiopatològics de lesió mitocondrial secundària: antiretrovirals, antibiòtics, antipsicòtics i monòxid de carboni.
No full text[cat] La present tesi doctoral consta de 5 publicacions i un manuscrit en preparació que aprofundeixen en l'estudi dels mecanismes de lesió mitocondrial secundaris al contacte amb determinats agents tòxics pel mitocondri (mitotòxics) com el virus de la immunodeficiència humana (VIH), el tractament antiretroviral (TARV) administrat per tractar aquesta infecció, un antibiòtic anomenat linezolid, diferents tipus d'antipsicòtics i el monòxid de carboni (CO). Tots aquests estudis s'han realitzat sempre ex-vivo emprant mostres humanes.Molts agents mitotòxics poden induir una lesió mitocondrial similar a la característica de les malalties mitocondrials primàries (innates i genètiques) amb les que sovint comparteixen simptomatologia clínica. Si bé les mitocondriopaties primàries no són massa freqüents, gran part de la població està exposada a molts d'aquests agents mitotòxics, molts dels quals són fàrmacs habitualment emprats en la pràctica clínica.Els tres primers treballs tracten sobre la toxicitat mitocondrial del VIH i el TARV i pretenen establir mètodes menys invasius per determinar l'abast de la lesió mitocondrial i la reversibilitat de la mateixa. A través de l'estudi de la funció mitocondrial en teixit muscular, el primer dels treballs valida l'ús de cèl·lules mononuclears de sang perifèrica com a model d'estudi de la funció mitocondrial en pacients VIH-positius que sota TARV desenvolupen una crisis d'hiperlactatèmia. Per això la resta de treballs s'han realitzat en cèl·lules mononuclears. Aquest estudi també valida l'aplicació d'un test d'esforç aeròbic de l'avantbraç, inicialment dissenyat per detectar disfunció mitocondrial primària (genètica), en el seguiment i diagnòstic de la disfunció mitocondrial secundària (tòxica) d'aquest tipus de pacients. Mitjançant tots aquests tests es determina que la funció mitocondrial en aquests individus es recupera un cop superat l'episodi d'hiperlactatèmia.El segon dels treballs determina la reversibilitat de la lesió mitocondrial induïda per un TARV de contrastada potència mitotòxica com són els dideoxinucleòsids quan són substituïts per un tractament teòricament menys lesiu pel mitocondri consistent en saquinavir potenciat amb ritonavir, tenofovir i enfuvirtide. Transcorreguts 6 mesos el canvi de TARV només aconsegueix una recuperació mitocondrial parcial amb una millora de la funció però no de la genètica (contingut en ADN mitocondrial o ADNmt) d'aquest orgànul.El tercer dels treballs avalua com la reducció de la dosi d'un dels components del TARV pot reduir la toxicitat mitocondrial d'aquesta teràpia. Concretament es valora la reducció de dosi de didanosina de 400 a 250 mg/d quan s'administra conjuntament amb tenofovir i nevirapina. Un any de tractament a elevades dosis d'aquest fàrmac disminueix el contingut en ADNmt i la funció mitocondrial en aquests pacients i l'administració consecutiva durant un altre any de la dosi reduïda de l'antiretroviral només permet una recuperació mitocondrial parcial que possibilita que es restableixi el contingut en ADNmt però no la funció d'aquest orgànul.El quart dels treballs avalua la toxicitat mitocondrial de l'antibiòtic linezolid en pacients que desenvolupen hiperlactatèmia associada al tractament prolongat amb aquest fàrmac. Estableix que el linezolid inhibeix la síntesi de proteïnes mitocondrials amb la conseqüent disminució de l'activitat enzimàtica de la cadena respiratòria d'aquest orgànul, malgrat l'augment en la taxa de transcripció mitocondrial (probablement en un intent infructuós d'augmentar la síntesi proteica bloquejada pel linezolid), i que aquesta podria ser la etiologia de la hiperlactatèmia associada a l'administració d'aquest antibiòtic. Totes aquestes alteracions són reversibles en retirar el fàrmac.El cinquè dels treballs estudia la toxicitat mitocondrial dels antipsicòtics, caracteritzada per la inhibició de la funció de la cadena respiratòria mitocondrial a nivell del complex I, i en el cas de l'haloperidol, a més a més, per l'augment de l'estrès oxidatiu. La capacitat mitotòxica dels antipsicòtics és proporcional al grau de manifestacions adverses de tipus extrapiramidal associades per a cadascun dels fàrmacs considerats (haloperidol > risperidona > clozapina), i podria ser doncs part de la base fisiopatològica responsable de l'aparició dels efectes secundaris. El sisè dels treballs (l'únic que no està publicat) empra l'estudi de la funció mitocondrial per avaluar les diferents opcions terapèutiques disponibles per tractar la intoxicació aguda per CO. El CO inhibeix la funció del complex IV de la cadena respiratòria independentment de la gravetat de la intoxicació, sense que augmenti el nivell d'estrès oxidatiu. En els intoxicats la funció mitocondrial es recupera al llarg del temps, de manera independent al tractament d'oxigen aplicat. Per tant, la recuperació de la funció mitocondrial només requereix una sessió d'oxigen hiperbàric per als intoxicats greus i l'oxigen normobàric per als lleus. Caldrà cerciorar aquests resultats un cop finalitzada la inclusió de pacients.[eng] This thesis is composed by 5 articles and one manuscript on preparation which analyse the mechanisms of mitochondrial lesion induced by some mitochondrial toxic (mitotoxic) agents such as the human immunodeficiency virus (HIV), the antiretroviral treatment (ARVT) used to treat HIV infection, an antibiotic named linezolid, different antipsychotics and carbon monoxide (CO). All these studies have been performed on humans samples that have been analysed ex-vivo.Many mitotoxic agents induce mitochondrial lesion and clinical symptoms common to primary (hereditary or genetic) mitochondriopathies. Primary mitochondrial disorders are not much frequent on general population, but many people is exposed to mitotoxic agents, many of them, because are routinely drugs in clinical practice.The first three studies of the present thesis analyse mitochondrial toxicity of both HIV and ARVT to establish less invasive methods to study mitochondrial dysfunction and the reversibility of HIV and ARVT-induced mitochondrial damage. They have validated the use of peripheral blood mononuclear cells and the forearm aerobic effort test to study mitochondrial lesion in HIV-infected and ARV-treated patients. These studies have determined that mitochondrial lesion reverts after an hyperlactatemic episode and partially recovers after changing potent mitotoxic ARVT (dideoxynucleosides) by theoretically less mitotoxic drugs (saquinavir/ritonavir+tenofovir+enfuvirtide) or after reducing ARV doses (didanosine from 400 to 250 mg/d+tenofovir+nevirapine).The forth study analyses mitochondrial toxicity of linezolid in patients suffering from hyperlactatemia. It demonstrates that linezolid inhibits mitochondrial protein synthesis and respiratory chain function, albeit increased mitochondrial transcription rates (maybe as an homeostatic intent to upregulate linezolid inhibited translation), and that all these mitochondrial abnormalities revert with linezolid withdrawal.The fifth study analyses mitochondrial toxicity of antipsychotics, which inhibit mitochondrial complex I function, and in case of haloperidol, indeed, increases oxidative stress. Antipsychotic mitochondrial lesion is proportional to their capacity to induce extrapiramidal disorders (haloperidol > risperidona > clozapina). Maybe mitochondrial lesion could be partially responsible of clinical adverse manifestations.The sixth study (unique work not published) use mitochondrial function monitorisation to evaluate different therapeutic options to treat acute CO intoxication. CO binds to mitochondrial complex IV inhibiting its function, independent to intoxication severity, without increasing oxidative stress. In CO poisoning mitochondrial function is recovered along the time independent to oxygen treatment option. Thus, recover of mitochondrial function after CO intoxication only requires of one hyperbaric oxygen session for severe poisoned patients and normobaric oxygen for the moderate ones, although these results have to be validated with a bigger amount of patients
The effects of pharmacogenetics on pharmacokinetics of artemisinin-based combinations in malaria patients
No full textMalaria is a vector-borne infectious disease caused by protozoan parasites of the genus Plasmodium. If not treated appropriately, human P. falciparum malaria can quickly become life-threatening, leading to an estimated 900’000 annual deaths globally. Key interventions to control malaria include prompt diagnosis and effective treatment with artemisinin-based combination therapies (ACTs), use of insecticide treated nets by people at risk, indoor residual spraying with insecticide to control the vector mosquitoes and intermittent preventive treatment for pregnant women (IPTp) and infants (IPTi).
Whether antimalarial treatments are effective or not, depends on parasite and host factors. The ability to define resistance leading to treatment failure has been greatly enhanced by our understanding of the underlying molecular mechanisms causing resistance in P. falciparum. However, the potential contribution of host genetic factors, particularly those associated with antimalarial drug metabolism, remains largely unexplored. The same applies for the basic mechanisms involved in the pharmacokinetics of antimalarial drugs and the link between antimalarial drug pharmacokinetics and treatment outcomes. Thus, the purpose of this thesis was to quantify the effects of pharmacogenetics on pharmacokinetics of ACTs.
Between 2007 and 2008, three in vivo studies were performed in Cambodia and Tanzania. Patients reporting with fever associated with an infection with Plasmodium falciparum were recruited and treated with ACTs according to the national guidelines in the respective country. In Cambodia, 64 patients were recruited for the treatment with artesunate–mefloquine and 61 for the treatment with dihydroartemisinine–piperaquine. In Tanzania, 150 were treated with artemether–lumefantrine. Blood samples for the pharmacokinetic analysis were taken before treatment and at several time points during and after treatment, e.g. on Days 1, 2 and 7 in all studies and in Cambodia also 1 hour after the first dose and on Day 14.
For the analysis of plasma samples collected during our studies, we developed a broad-range liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) assay covering 14 of the currently in-use antimalarial drugs and their metabolites. The assay requires only as little as 200 μl of plasma and is a major improvement over previous methods in terms of convenience, sensitivity, selectivity and throughput. The method was validated according to well-established recommendations. The assay was first used for the analysis of the baseline samples collected in our in vivo studies. In all studies more than half of the patients recruited had still antimalarials in their blood. Theses findings enabled us to get a better assessment of the antimalarials circulating in the local population, and hence of the drug pressure on the parasites in both countries.
Single nucleotide polymorphisms (SNPs) in genes encoding enzymes associated with antimalarial drug metabolism, i.e. cytochrome P450 isoenzymes (CYP) and N-acetyltransferase 2 (NAT2), were analyzed. Based on our previous experience, we developed a DNA microarray to affordably generate SNP data. However, after comparison of microarray data and sequencing data, we concluded that the major limit of the microarray technology was lack of robustness which could not be compensated by superior cost-effectiveness. Consequently, the pharmacogenetic profiles of the patients from the three in vivo studies were assessed by direct sequencing of genomic DNA. Whereas for most SNPs allele frequencies were similar in both populations, we found significant inter-ethnic differences in the distribution of genotypes of certain enzymes, namely CYP2D6, CYP3A4/5 and NAT2. Is has been shown that the human CYP3A subfamily plays a dominant role in the metabolic elimination of more drugs than any other biotransformation enzyme. Therefore, our findings might have implications for treatment policies of not only antimalarials and the widely introduced ACTs in particular, but any other drugs metabolized by these enzymes.
To quantify the effect of pharmacogenetics on pharmacokinetics of ACTs we developed population pharmacokinetic models. The pharmacokinetic parameters we estimated in our models were in agreement with those from previous studies. In order to account for parts of the inter-individual variability in drug-metabolizing capacity of the liver we included pharmacogenetic data as covariate. For artemether, we found that 9% of the inter-individual variability in clearance could be explained by the genotype of CYP3A5 (reference allele versus variant allele CYP3A5*3). Heterozygous carriers showed a reduction in clearance of 34%. The alterations in clearance were less pronounced for lumefantrine (increase in clearance of 12% in homozygous carriers of variant allele CYP3A4*1B, explaining 2% of the inter-individual variability in clearance) and mefloquine (decrease in clearance of 14% in carriers of homozygous variant allele CYP3A5*5, explaining 1% of the inter-individual variability in clearance). These data might partially provide an explanation for the differences in drug efficacy observed with artemether–lumefantrine combination treatment.
In conclusion, we were able to show that there is a correlation between the pharmacogenetic profile of the host and the pharmacokinetics of antimalarial drugs administered in malaria patients. These results suggest that pharmacogenetics could be one of the basic mechanisms involved in the pharmacokinetics of antimalarial drugs. The knowledge gained from this study could facilitate the selection process of first-line treatment for malaria and would allow dosing adaptation based on the pharmacogenetic profile of the population. Such adaptations are needed especially in the most vulnerable groups, including infants, pregnant women, and those with prevalent co-morbidities, where often therapeutic antimalarial drug concentrations over time are not achieved
The Effects of Pharmacogenetics on Pharmacokinetics\ud of Artemisinin-Based Combinations in Malaria Patients
No full textMalaria is a vector-borne infectious disease caused by protozoan parasites of the genus Plasmodium. If not treated appropriately, human P. falciparum malaria can quickly become life-threatening, leading to an estimated 900’000 annual deaths globally. Key interventions to control malaria include prompt diagnosis and effective treatment with artemisinin-based combination therapies (ACTs), use of insecticide treated nets by people at risk, indoor residual spraying with insecticide to control the vector mosquitoes and intermittent preventive treatment for pregnant women (IPTp) and infants (IPTi). Whether antimalarial treatments are effective or not, depends on parasite and host factors. The ability to define resistance leading to treatment failure has been greatly enhanced by our understanding of the underlying molecular mechanisms causing resistance in P. falciparum. However, the potential contribution of host genetic factors, particularly those associated with antimalarial drug metabolism, remains largely unexplored. The same applies for the basic mechanisms involved in the pharmacokinetics of antimalarial drugs and the link between antimalarial drug pharmacokinetics and treatment outcomes. Thus, the purpose of this thesis was to quantify the effects of pharmacogenetics on pharmacokinetics of ACTs. Between 2007 and 2008, three in vivo studies were performed in Cambodia and Tanzania. Patients reporting with fever associated with an infection with Plasmodium falciparum were recruited and treated with ACTs according to the national guidelines in the respective country. In Cambodia, 64 patients were recruited for the treatment with artesunate–mefloquine and 61 for the treatment with dihydroartemisinine–piperaquine. In Tanzania, 150 were treated with artemether–lumefantrine. Blood samples for the pharmacokinetic analysis were taken before treatment and at several time points during and after treatment, e.g. on Days 1, 2 and 7 in all studies and in Cambodia also 1 hour after the first dose and on Day 14. For the analysis of plasma samples collected during our studies, we developed a broad-range liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) assay covering 14 of the currently in-use antimalarial drugs and their metabolites. The assay requires only as little as 200 μl of plasma and is a major improvement over previous methods in terms of convenience, sensitivity, selectivity and throughput. The method was validated according to well-established recommendations. The assay was first used for the analysis of the baseline samples collected in our in vivo studies. In all studies more than half of the patients recruited had still antimalarials in their blood. Theses findings enabled us to get a better assessment of the antimalarials circulating in the local population, and hence of the drug pressure on the parasites in both countries. Single nucleotide polymorphisms (SNPs) in genes encoding enzymes associated with antimalarial drug metabolism, i.e. cytochrome P450 isoenzymes (CYP) and N-acetyltransferase 2 (NAT2), were analyzed. Based on our previous experience, we developed a DNA microarray to affordably generate SNP data. However, after comparison of microarray data and sequencing data, we concluded that the major limit of the microarray technology was lack of robustness which could not be compensated by superior cost-effectiveness. Consequently, the pharmacogenetic profiles of the patients from the three in vivo studies were assessed by direct sequencing of genomic DNA. Whereas for most SNPs allele frequencies were similar in both populations, we found significant inter-ethnic differences in the distribution of genotypes of certain enzymes, namely CYP2D6, CYP3A4/5 and NAT2. Is has been shown that the human CYP3A subfamily plays a dominant role in the metabolic elimination of more drugs than any other biotransformation enzyme. Therefore, our findings might have implications for treatment policies of not only antimalarials and the widely introduced ACTs in particular, but any other drugs metabolized by these enzymes. To quantify the effect of pharmacogenetics on pharmacokinetics of ACTs we developed population pharmacokinetic models. The pharmacokinetic parameters we estimated in our models were in agreement with those from previous studies. In order to account for parts of the inter-individual variability in drug-metabolizing capacity of the liver we included pharmacogenetic data as covariate. For artemether, we found that 9% of the inter-individual variability in clearance could be explained by the genotype of CYP3A5 (reference allele versus variant allele CYP3A5*3). Heterozygous carriers showed a reduction in clearance of 34%. The alterations in clearance were less pronounced for lumefantrine (increase in clearance of 12% in homozygous carriers of variant allele CYP3A4*1B, explaining 2% of the inter-individual variability in clearance) and mefloquine (decrease in clearance of 14% in carriers of homozygous variant allele CYP3A5*5, explaining 1% of the inter-individual variability in clearance). These data might partially provide an explanation for the differences in drug efficacy observed with artemether–lumefantrine combination treatment. In conclusion, we were able to show that there is a correlation between the pharmacogenetic profile of the host and the pharmacokinetics of antimalarial drugs administered in malaria patients. These results suggest that pharmacogenetics could be one of the basic mechanisms involved in the pharmacokinetics of antimalarial drugs. The knowledge gained from this study could facilitate the selection process of first-line treatment for malaria and would allow dosing adaptation based on the pharmacogenetic profile of the population. Such adaptations are needed especially in the most vulnerable groups, including infants, pregnant women, and those with prevalent co-morbidities, where often therapeutic antimalarial drug concentrations over time are not achieve
The variable finesse locking technique
No full textVirgo is a power recycled Michelson interferometer, with 3 km long Fabry-Perot cavities in the arms. The locking of the interferometer has been obtained with an original lock acquisition technique. The main idea is to lock the instrument away from its working point. Lock is obtained by misaligning the power recycling mirror and detuning the Michelson from the dark fringe. In this way, a good fraction of light escapes through the antisymmetric port and the power build-up inside the recycling cavity is extremely low. The benefit is that all the degrees of freedom are controlled when they are almost decoupled, and the linewidth of the recycling cavity is large. The interferometer is then adiabatically brought on to the dark fringe. This technique is referred to as variable finesse, since the recycling cavity is considered as a variable finesse Fabry-Perot. This technique has been widely tested and allows us to reach the dark fringe in few minutes, in an essentially deterministic way
A simple line detection algorithm applied to Virgo data
No full textWe propose a new method for the detection of spectral lines in random noise. It mimics the processing scheme of matching filtering, i.e., a whitening procedure combined with the measurement of the correlation between the data and a template. Thanks to the original noise spectrum estimate used in the whitening procedure, the algorithm can easily be tuned to various types of noise. It can thus be applied to the data taken from a wide class of sensors. This versatility and its small computational cost make this method particularly well suited for real-time monitoring in gravitational wave experiments. We show the results of its application to Virgo C4 commissioning data
The Virgo automatic alignment system
No full textThe automatic alignment system of the Virgo interferometer differs substantially from those used in similar experiments, since it uses a variant of the Anderson technique. This implies a completely different control topology with respect to other detectors, and the main feature is a strong coupling of different degrees of freedom in the optical signals. It also provides two extra output ports in which differential wave-front sensors can be placed, namely the light transmitted by the Fabry-Perot arm cavities. We report on the first experimental demonstration of this technique on a large scale recycled interferometer, and on the present status of the automatic alignment system
A first study of environmental noise coupling to the Virgo interferometer
No full textDuring the commissioning of the Virgo interferometer, a search for environmental noise contributions to the dark fringe signal was undertaken. Dedicated tests have been performed to identify major sources of disturbances and to understand the coupling mechanism with the interferometer. The major effect is due to seismic/acoustic noise coupling to the laser beam before the input mode cleaner, then propagating as beam. power noise to the ITF dark fringe output signal. In this paper we illustrate the tests performed and preliminary results of our investigation
