5 research outputs found
Author Correction: Retention of Mitochondria in Mature Human Red Blood Cells as the Result of Autophagy Impairment in Rett Syndrome (Scientific Reports, (2017), 7, 1, (12297), 10.1038/s41598-017-12069-0)
No full textTargeted delivery of advanced functionality by nanomaterials : focus on nucleic acids delivery by novel block copolymers
No full textAbstract: Smart drug delivery systems are versatile examples of successful nanomedicine with
potential in diagnostics and medical therapy. The thesis presents selected
approaches in current drug delivery systems in the (pre-)clinical trials, and deals with
potential side effects, including complement activation and hypersensitivity reactions
as well as the design requirements of the delivery systems. Furthermore, it presents
approaches of cationic block copolymers, which are capable to condense negatively
charged nucleic acid molecules such as plasmid deoxyribonucleic acid (pDNA) and
small interfering ribonucleic acid (siRNA) with the aim of efficient cell gene delivery
and specific gene suppression, respectively.
The first part addresses the transfection efficiency of circular versus linearized
plasmid DNA using a green fluorescent protein expressing vector with Lipofectamine
2000 and linear 25 kDA polyethylenimine (PEI). These results show a considerably
improved transfection efficiency with the circular compared to the linearized DNA for
the two transfection reagents. The electron microscopy images with Lipofectamine or
PEI demonstrate that the circular DNA gives rise to random coil appearance of
compact, spherical shape, while linearized DNA appear as worm-like strands.
Particle size and shape are important in the cell biology of endocytosis and
phagocytosis. The findings indicate that the shape of the transfection particle is vital
for successful gene transfer.
To develop a delivery system for gene therapy, two cationic diblock copolymers
consisting of primary and tertiary amines were synthesized and analyzed with
respect to DNA condensation properties, morphology of the condensed plasmid DNA
and transfection efficiency using two cell lines. This study revealed proof-of-concept
showing an order of magnitude lower transfection efficiency of primary amine diblock
copolymers compared to PEI after 48 h with increasing plasmid DNA concentration.
Furthermore, primary amines compared to tertiary ones show much stronger binding
to DNA and improved transfection efficiency. Transmission electron and atomic force
microscopy data revealed morphologies of primary and tertiary amines regarding the
condensation of the plasmid DNA, in agreement with the transfection efficiency.
In a second part the design and characterization of pentablock-based polyplexes
based on the combination of cationic pentablock copolymers with folic acid
functionalized copolymers for targeted specific siRNA delivery is described. The
achieved 31 % knockdown efficiency shows its potential regarding cancer gene
therapy. The pentablock architecture allows the formation of highly stable
micelleplexes of (21 ± 3) nm in 10 mM PBS buffer solution with a neutral surface
charge, excellent siRNA condensation properties, outstanding colloidal stability in
10 % serum over 24 h and biocompatibility deduced from the absence of
considerable cytotoxicity even after 48 h incubation. Furthermore, selective delivery
of the siRNA could be proven by the introduction of a ligand-linked block copolymer,
resulting in 31 % compared to 8 % gene suppression for targeted a non-targeted
micelleplexes. This pentablock-based delivery system might yield impact to future
delivery systems as well as being a potential platform to be applied in vivo for cancer
gene therapy. ---------- Zusammenfassung
Innerhalb des Bereichs der Nanomedizin weisen intelligente Wirkstoffabgabesysteme
ein großes Potenzial auf, sowohl hinsichtlich der Diagnostik wie auch der
medizinischen Therapie. Die vorliegende Arbeit stellt im Rahmen einer
Literaturrecherche ausgewählte Wirkstoffabgabesysteme vor, welche sich in (vor-)
klinischen Studien befinden, den Nebenwirkungen welche durch diese entstehen
können, im speziellen der Komplementaktivierung und Überempfindlichkeitsreaktionen,
sowie deren Konstruktionsanforderungen. Des weiteren werden in einem
experimentellen Teil kationische Block-Kopolymere präsentiert, welche in der Lage
sind, negativ geladene Nukleinsäuremoleküle zu binden - wie etwa Plasmid
Desoxyribonukleinsäure (pDNA) und kleine interferierende Ribonukleinsäuren
(siRNA) - mit dem Ziel der Transfektion von fremder DNA in die Wirtszellen und
damit der spezifischen Unterdrückung der Genexpression.
Der erste Teil der experimentellen Arbeit untersucht die Transfektionseffizienz von
zirkulärer gegenüber linearisierter Plasmid-DNA mittels eines Vektors, welcher ein
grün fluoreszierendes Protein exprimiert. Transfiziert wurde einerseits mit
Lipofectamine 2000 und andererseits mit linearem 25 kDa Polyethylenimin (PEI),
zwei etablierten Transfektionsreagenzien. Die Ergebnisse zeigen eine wesentlich
verbesserte Transfektionseffizienz der zirkulären, verglichen mit der linearisierten
DNA für beide Transfektionsreagenzien. Die elektronenmikroskopischen Bilder von
Lipofectamine sowie PEI komplexiert mit DNA zeigen, dass die zirkuläre DNA
zufällige, kompakte Kugelformen bildet, während die linearisierte DNA wurmartige
Stränge aufweist. Partikelgröße und -form spielen in der Zellbiologie eine wichtige
Rolle bei der Endozytose und Phagozytose. Die Ergebnisse legen die Vermutung
nahe dass die Form der zu transfizierenden DNA-Transfektions-Komplexen eine
wichtige Rolle einnimmt für einen erfolgreichen Gentransfer.
Für die Entwicklung eines intelligenten Wirkstoffabgabe-Systems für die Gentherapie
wurden zwei kationische Diblock-Kopolymere, die aus primären und tertiären Aminen
bestehen synthetisiert und im Hinblick auf deren DNA-Kondensationseigenschaften,
Morphologie der kondensierten Plasmid-DNA sowie Transfektionseffizienz unter
Verwendung von zwei Zelllinien analysiert. Die Studie bestätigt trotz einer um den
Faktor 10 schwächeren Transfektionseffizienz der primären Amin-DiblockKopolymeren
im Vergleich zu PEI nach 48 h mit zunehmender pDNA Konzentration
eine Bestätigung des Konzepts. Außerdem weisen die primären Amin-Block-
Kopolymere im Vergleich zu den tertiären eine viel stärkere Komplexbildung der DNA
auf - wie transmissions-elektronen- und rasterkraft-mikroskopische Daten ergaben -
als auch eine verbesserte Transfektionseffizienz. Diese physikalischmorphologischem
Erkenntnisse über die Kondensation der primären und tertiären
Amine mit Plasmid-DNA konnten mittels der biologischen Transfektionseffizienzdaten
validiert werden.
Der zweite Teil der experimentellen Arbeit befasst sich mit dem Design sowie der
Charakterisierung von pentablock-basierten Polyplexen für einen gezielten siRNA
Transport. Diese Polyplexe beruhen auf einer Kombination von kationischen
Pentablock-Kopolymeren mit folsäure-funktionalisierten Kopolymeren. Die erreichten
31% Gen-Suppression in einem Krebszellkulturmodell, zeigen das Potenzial des
Wirkstoffabgabesystems in Bezug auf eine Krebstherapie auf. Die Architektur
ermöglicht die Bildung von sehr stabilen Mizellen mit einer Grösse von (21 ± 3) nm in
10 mM PBS Pufferlösung, eine neutrale Oberflächenladung, ausgezeichneten siRNAKondensationseigenschaften,
hervorragender kolloidaler Stabilität in
Zellkulturmedium supplementiert mit 10 % Serum über 24 h, sowie guter
Biokompatibilität aufgrund fehlender erheblicher Zytotoxizität auch nach 48 h
Inkubation in einem Zellkulturmodell. Ferner konnte durch die Einführung eines
liganden-gebundenen Block-Kopolymers der selektive Transport der siRNA
nachgewiesen werden, was zu einer Gen Suppression von 31% gegenüber 8% nicht
funktionalisierter Polyplexen führte. Das in dieser Arbeit eingeführte und
charakterisierte pentablock-basierte Wirkstoffabgabesystem könnte Auswirkungen
auf das Design zukünftiger Wirkstoffabgabesystem haben als auch als eine
potentielle Plattform für in vivo-Krebsgentherapien angewendet werden
Impact of safety-related dose reductions or discontinuations on sustained virologic response in HCV-infected patients: Results from the GUARD-C Cohort
No full textBackground: Despite the introduction of direct-acting antiviral agents for chronic hepatitis C virus (HCV) infection, peginterferon alfa/ribavirin remains relevant in many resource-constrained settings. The non-randomized GUARD-C cohort investigated baseline predictors of safety-related dose reductions or discontinuations (sr-RD) and their impact on sustained virologic response (SVR) in patients receiving peginterferon alfa/ribavirin in routine practice. Methods: A total of 3181 HCV-mono-infected treatment-naive patients were assigned to 24 or 48 weeks of peginterferon alfa/ribavirin by their physician. Patients were categorized by time-to-first sr-RD (Week 4/12). Detailed analyses of the impact of sr-RD on SVR24 (HCV RNA <50 IU/mL) were conducted in 951 Caucasian, noncirrhotic genotype (G)1 patients assigned to peginterferon alfa-2a/ribavirin for 48 weeks. The probability of SVR24 was identified by a baseline scoring system (range: 0-9 points) on which scores of 5 to 9 and <5 represent high and low probability of SVR24, respectively. Results: SVR24 rates were 46.1 % (754/1634), 77.1% (279/362), 68.0% (514/756), and 51.3% (203/396), respectively, in G1,2, 3, and 4 patients. Overall, 16.9% and 21.8% patients experienced ≥1 sr-RD for peginterferon alfa and ribavirin, respectively. Among Caucasian noncirrhotic G1 patients: female sex, lower body mass index, pre-existing cardiovascular/pulmonary disease, and low hematological indices were prognostic factors of sr-RD; SVR24 was lower in patients with ≥1 vs. no sr-RD by Week 4 (37.9% vs. 54.4%; P = 0.0046) and Week 12 (41.7% vs. 55.3%; P = 0.0016); sr-RD by Week 4/12 significantly reduced SVR24 in patients with scores <5 but not ≥5. Conclusions: In conclusion, sr-RD to peginterferon alfa-2a/ribavirin significantly impacts on SVR24 rates in treatment-naive G1 noncirrhotic Caucasian patients. Baseline characteristics can help select patients with a high probability of SVR24 and a low probability of sr-RD with peginter-feron alfa-2a/ribavirin. © 2016 Foster et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Maternal Child Attachment and Perinatal Depression
No full textABSTRACT
Traditionally, pregnancy has been thought of as a period of well-being and happiness. The pregnancy state itself has been thought to protect women from depression. However, women of child-bearing age frequently suffer from major depression. Approximately 10 to 15% of women experience a clinically significant major depressive episode during pregnancy or the early postpartum period. These prevalences predominantly reflect rates of depressive symptoms in developed countries; there is evidence that rates of depression change aspect widely in non-developed countries. In addition to the distress and impairment experienced by depressed women, depression during this time period is associated with further adverse outcomes for both mother and child. Women who experience perinatal depressive episodes are at increased risk for subsequent episodes of both postpartum and non-postpartum depression.
Anxiety symptoms are frequently reported by pregnant women and are often considered as part of the normal psychic experiences of pregnancy, especially if they are focused on the baby's health or on future maternal competencies.
The emotional image of the baby inside is what is called the mother fetus relationship.
Cranley (1981) describes the nature of mother’s experiences as ‘physical and kinesthetic awareness of the fetus’, and an ‘intellectual knowledge of her child’.
Nowadays, the concept of prenatal attachment is more accurately defined and it generally refers to the maternal–fetal relationship, which normally develops during the pregnancy; it represents the earlier internalized representation of the fetus that both parents typically acquire and elaborate. Pregnancy can also represent a crisis period for many women, with manifest effect on antenatal attachment. Condon and Corkindale (1997) explore the hypothesis that feelings of anxiety or depression and lack of social support would be an interference issue in the development of maternal antenatal attachment. Women characterized by low attachment are associated with high levels of depression and anxiety, weak external social support, and high control and criticism in the partner relationship.
Antepartum depression is also common in women with a history of depressive illness, such that some researchers now believe pregnancy to be a risk factor for a mood disorder in those with such a history.
Despite the prevalence of depression during pregnancy and the growing body of literature associated with its treatment, whether pharmacologic or otherwise, large numbers of women are untreated.
Also “parental-fetal attachment” or perinatal term has been created to define the specific bond that parents develop towards the fetus during pregnancy. Since Winnicott’s (1958) concept of a pregnant woman’s “primary maternal preoccupation”, the quality of the parent-prenatal emotional bond has been considered as particularly important for the subsequent attachment relationship and for the infant’s psychological development.
In 1981 Cranley defined the “maternal-fetal attachment” construct and created a tool to measure it. The author describes the nature of mother’s experiences as ‘physical and kinesthetic awareness of the fetus’, and an ‘intellectual knowledge of her child’. Nowadays a specific field of research which studies the characteristics of the emotional bond which parents-to-be develop is progressively growing. Some aspects of current knowledge relating to development of prenatal attachment and the implication of low levels of prenatal attachment and risk to the fetus, is considered in this study.
Aim of the study:
The aim of this study was to assess the quality of maternal child attachment on mothers enrolled in post partum during the first month after delivery .The sample has been compared with a group of women enrolled during the first month of pregnancy and followed for twelve months like the sample of the previous study. Furthermore, we investigated the differences between the women enrolled in first month of pregnancy and after delivery. We tried to find a correlation looking at score on maternal attachment scale (MAAS) and a possible development of depression (EPDS ≥12), anxiety symptoms (STAI-Y ≥40). Even risk factors during pregnancy has been evaluated to assess the specific role of antenatal attachment as risk factor for depression (EPDS≥12), as anxiety symptoms (STAI ≥ 40) during pregnancy.
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Methods: The PND-ReScU II® study is a naturalistic longitudinal study deputated to found risks factors and a possible role of psychiatric and psychopathological prevention on perinatal disorders. This study has been performed in five Clinical Center in Tuscany (Italy) in cooperation with U.O. II Department of Psychiatry and Gynecology Department of the Azienda Ospedaliera Universitaria Pisana (AOUP). Women has been randomized and enrolled in the study during pregnancy on the first month and on the first month after delivery.
From January to August 2010 a sample of women (N= 946) by the Perinatal Research and Screening Unit (PND-ReScU). The Perinatal Depression-Research and Screening Unit (PND-ReScU) is based on an ongoing collaboration between the Department of Obstetrics and Gynecology and the Department of Psychiatry, Neurobiology, Pharmacology, and Biotechnologies of the AUOP. The primary aim of the PND-ReScU was to evaluate the effectiveness of screening for early identification and the intervention strategies to reduce and treat mood disorders in the perinatal period.
Furthermore, PND-ReScU aims were looking for individualized a battery of instruments that can be easily administered in a primary prevention setting.
Women were recruited for the study during pregnancy, at the time of delivery of the pregnancy book, or in the immediate post-partum period (during hospitalization). To have a significative relevance it was estimated to enroll 320 women during post partum period and 320 women during pregnancy. In June 2010, 491 women were recruited during post partum and at the end of August 2010 there were enrolled 455 women during pregnancy.
Instruments:
Symptoms of maternal depression were assessed using the 10-item Edinburgh Postnatal Depression Scale (Cox et al., 1987). The Post-partum Depression Predictors Inventory-Revised (PDPI-R) (Beck, 2002) was used to identify the risk factors for PPD. Prenatal and postnatalmaternal attachment were assessed using the Maternal Antenatal Attachment Scale (MAAS) and Maternal and paternal antenatal attachment scale (MPAS). Anxiety symptoms were assessed using STAI-Y ( State Trait Anxiety Inventory form Y-1.)
Statistical analysis:
Data are presented as means (standard deviations), or percentages.
Chi-square tests were used to compare percentages and
ANOVA were used to compare mean scores.
Using analysis of variance (ANOVA) was able to compare two groups of data comparing the internal variability in these groups with the variability between groups.
To check the intensity and direction of the relationships between depression and maternal attachment to the fetus and risk factors, was performed Pearson bivariate correlation.
Analyses were conducted using SPSS, version 15.
Results:
Eligible women were 1363 , 455 (48%) recruited during pregnancy and 491 (52%) during post partum; among them, 417 (30,6%) refusedto partecipate in the study. The mean age in the first group G1 is 32.75± 4,84 and in the second gropu G2 is 33.39±4,81 years old, and in unrolled women (G3) is 32.5 ± 5.7 years old. Other sociodemographic variabilites had been evaluated and χ2 has been performed test fo find significant differences among the three groups. Most of the women of the three groups were married (G 1: n=381, 90.9%; G 2: n=389, 89.8%; G3 n=353, 87.2%); there were no differences in the groups (χ2= 8.48; p=0.01). Looking at the sample most part of women had Italian nationality bwhile unenrolled women showed almosty foreign nationality (χ2= 63.12*, p< 0,01) . 61.6% of the sample is composed of women at the first pregnancy.
A comparison between the scales administered for the two groups ( G1, G2) was performed at the first month of post partum period at T4 during the first month of pregnancy ( G1,T4; G2 T4 bis). The EPDS mean score s were 3,37 (±3,37) in the first group and the second group scored 6,3(±4,2; p=0.01) , the STAI mean scores were 45,4(±3,8) and 44,6(±3,7) in G1 and G2 respectively.
The PDPI-R mean scores were 27,5(±2,8) in G1 and 3,83 (±3,2) in G2 (p<.003) during pregnancy and 3.5 (±3.4) in G1 and 4.95(3,6) in G2 (p<.001) during post partum.
The average of the MAAS total scores at T2 ( 6° month of pregnancy) was 76.95 ± 6.3, while at T3( 8° month of pregnancy) , the average was 78.54 ± 6.29.
Considering the MAAS T2 Preoccupation subscale the average is 28.12 ± 4.2 and 29.33 ± 4.21 at T3.
Considering the Quality of Attachment subscale MAAS, the average was 47.2 ± 3.29, and 47.71 ± 2.98 at T2 and T3 respectively. Correlation between depression during pregnancy, good antenatal attachment , anxiety symptoms and risk factors is reported for PDD during pregnancy
In our sample we don’t find any association between antenatal maternal attachment and demographic characteristics except for women in their first pregnancy in which we discover higher MAAS scores than other women in sample.
Conclusions:
In the last five decades the study on the maternal attachment show a primary role for the future development of the newborn. For this reason it is essential that treatment providers in obstetric offices, primary care settings, and mental health clinics be attuned to the signs of anxiety disorders (Weisberg and Paquette, 2002). In our research we try to find the consequences of depression on newborns. We find a negative relationship between the develop of a attachment and depressive symptoms during pregnancy .
The quality of attachment in this record seems to be poor in mothers with depression and more risks factor for PDD during pregnancy.
In particular, as regards the analysis of the qualitative aspects of attachment in the second and third trimesters of pregnancy, the data confirmed a negative correlation between attachment, depressive symptoms and risk factors for the whole period of pregnancy.
Analysis of data for the period following childbirth, we found that women enrolled in the first month post-partum have an increased vulnerability to risk factors for developing postpartum depression than women enrolled in the first month of pregnancy , both with respect to the period of pregnancy (p <.003) that the postpartum period (p <.001); probably early screening and the role of caregivers in this study may have acted as protective factors.
Women enrolled in post-partum seem to have a different perception about respect to family support, support from friends and the partner, and seem to experienced higher difficulties regarding health problems, sleep and temperament in the newborn. The women in group 2, as assumed from the data of PDPI-R, were significantly more depressed than in group 1, presenting an attachment toward their child's worst than the first group. Preliminary data of our study, which appear to be the first, to our knowledge, because explores both pregnant and post-partum periods, seem to confirm this assumption and emphasize the importance of an early screening of depressive phenomenal at the earliest stages of pregnancy
