Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
1.
Acc Chem Res ; 57(7): 1019-1031, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38471078

RESUMO

Base excision repair (BER) enzymes are genomic superheroes that stealthily and accurately identify and remove chemically modified DNA bases. DNA base modifications erode the informational content of DNA and underlie many disease phenotypes, most conspicuously, cancer. The "OG" of oxidative base damage, 8-oxo-7,8-dihydroguanine (OG), is particularly insidious due to its miscoding ability that leads to the formation of rare, pro-mutagenic OG:A mismatches. Thwarting mutagenesis relies on the capture of OG:A mismatches prior to DNA replication and removal of the mis-inserted adenine by MutY glycosylases to initiate BER. The threat of OG and the importance of its repair are underscored by the association between inherited dysfunctional variants of the MutY human homologue (MUTYH) and colorectal cancer, known as MUTYH-associated polyposis (MAP). Our functional studies of the two founder MUTYH variants revealed that both have compromised activity and a reduced affinity for OG:A mismatches. Indeed, these studies underscored the challenge of the recognition of OG:A mismatches that are only subtly structurally different than T:A base pairs. Since the original discovery of MAP, many MUTYH variants have been reported, with most considered to be "variants of uncertain significance." To reveal features associated with damage recognition and adenine excision by MutY and MUTYH, we have developed a multipronged chemical biology approach combining enzyme kinetics, X-ray crystallography, single-molecule visualization, and cellular repair assays. In this review, we highlight recent work in our laboratory where we defined MutY structure-activity relationship (SAR) studies using synthetic analogs of OG and A in cellular and in vitro assays. Our studies revealed the 2-amino group of OG as the key distinguishing feature of OG:A mismatches. Indeed, the unique position of the 2-amino group in the major groove of OGsyn:Aanti mismatches provides a means for its rapid detection among a large excess of highly abundant and structurally similar canonical base pairs. Furthermore, site-directed mutagenesis and structural analysis showed that a conserved C-terminal domain ß-hairpin "FSH'' loop is critical for OG recognition with the "His" serving as the lesion detector. Notably, MUTYH variants located within and near the FSH loop have been associated with different forms of cancer. Uncovering the role(s) of this loop in lesion recognition provided a detailed understanding of the search and repair process of MutY. Such insights are also useful to identify mutational hotspots and pathogenic variants, which may improve the ability of physicians to diagnose the likelihood of disease onset and prognosis. The critical importance of the "FSH" loop in lesion detection suggests that it may serve as a unique locus for targeting probes or inhibitors of MutY/MUTYH to provide new chemical biology tools and avenues for therapeutic development.


Assuntos
Neoplasias Colorretais , Reparo do DNA , Guanina/análogos & derivados , Humanos , Adenina/química , Escherichia coli/química , Dano ao DNA , DNA/genética , DNA/química , Hormônio Foliculoestimulante/genética
2.
Nucleic Acids Res ; 51(3): 1034-1049, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36631987

RESUMO

DNA glycosylase MutY plays a critical role in suppression of mutations resulted from oxidative damage, as highlighted by cancer-association of the human enzyme. MutY requires a highly conserved catalytic Asp residue for excision of adenines misinserted opposite 8-oxo-7,8-dihydroguanine (OG). A nearby Asn residue hydrogen bonds to the catalytic Asp in structures of MutY and its mutation to Ser is an inherited variant in human MUTYH associated with colorectal cancer. We captured structural snapshots of N146S Geobacillus stearothermophilus MutY bound to DNA containing a substrate, a transition state analog and enzyme-catalyzed abasic site products to provide insight into the base excision mechanism of MutY and the role of Asn. Surprisingly, despite the ability of N146S to excise adenine and purine (P) in vitro, albeit at slow rates, N146S-OG:P complex showed a calcium coordinated to the purine base altering its conformation to inhibit hydrolysis. We obtained crystal structures of N146S Gs MutY bound to its abasic site product by removing the calcium from crystals of N146S-OG:P complex to initiate catalysis in crystallo or by crystallization in the absence of calcium. The product structures of N146S feature enzyme-generated ß-anomer abasic sites that support a retaining mechanism for MutY-catalyzed base excision.


Assuntos
DNA Glicosilases , Neoplasias , Humanos , Cálcio , Reparo do DNA , Mutação , Purinas , DNA Glicosilases/metabolismo
3.
J Obstet Gynaecol Res ; 49(2): 614-624, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36424698

RESUMO

AIM: To evaluate the effects of COVID-19 disease and the trimester in which the disease is diagnosed on obstetric and neonatal outcomes. METHODS: This retrospective cohort study was conducted with 358 patients who had or had not been diagnosed with COVID-19 during their pregnancy, had a miscarriage or had given birth. RESULTS: COVID-19 disease during pregnancy was associated with higher maternal hypertensive disease, preterm birth, low birth weight, low first- and fifth-minute Apgar scores, and need for neonatal intensive care unit. The incidence of preterm birth, low birth weight, low first- and fifth-minute Apgar scores, and need for neonatal intensive care unit in those diagnosed with COVID-19 in the second trimester was significantly higher than those diagnosed with COVID-19 in other trimesters. The frequency of cesarean section was observed most in those diagnosed with COVID-19 in the 3rd trimester, while it was observed in those diagnosed with COVID-19 at least in the first trimester. CONCLUSION: The presence of COVID-19 during pregnancy may be associated with an increased risk of iatrogenic preterm birth. The frequency of preterm birth in pregnant women diagnosed with COVID-19 in the second trimester is higher than in pregnant women diagnosed with COVID-19 in other trimesters. As the pregnancy trimester at the time of diagnosis progresses, the frequency of cesarean section increases. While the risk of maternal hypertensive disease increases more in pregnant women with COVID-19, the effect of the trimester in which COVID-19 was passed on the risk of maternal hypertensive disease is not observed.


Assuntos
COVID-19 , Hipertensão , Pré-Eclâmpsia , Nascimento Prematuro , Gravidez , Recém-Nascido , Humanos , Feminino , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , COVID-19/epidemiologia , Cesárea , Estudos Retrospectivos , Terceiro Trimestre da Gravidez
4.
J Relig Health ; 62(2): 1379-1393, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36823257

RESUMO

The current study seeks to analyze Muslim experiences of communicative diseases with a focus on the psychosocial impacts and public, communal, and personal responses of Muslim populations throughout history. By examining a selection of plague outbreaks between the 8-19th centuries across the lands broadly defined as the Islamic Mediterranean (Varlik, 2017), the guidelines and coping mechanisms that Muslims extracted from their traditional sources are highlighted. This historical perspective contributes to a better understanding of the psychological and social aspects of pandemics for the Muslim community, specifically for the role played by faith and spirituality as determinants of psychological well-being in Muslims' perceptions and responses. We suggest that such an understanding is especially useful for contemporary mental health practitioners working with Muslim patients through the global COVID-19 pandemic.


Assuntos
COVID-19 , Peste , Humanos , Islamismo/psicologia , Pandemias , Civilização
5.
Clin Invest Med ; 39(6): 27497, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27917788

RESUMO

PURPOSE: The purpose of this study was to examine the efficacy of a long-term training program of 10 weeks on static and dynamic balance parameters in a young healthy population. METHODS: Participants were 35 young healthy female subjects. Balance measurements were done using the Flamingo Balance Test (FBT) for static balance and the Star Excursion Balance Test (SEBT) for dynamic balance. RESULTS: Dynamic balance points increased and static balance points decreased after a 10 week training protocol compared with before training, indicating improvement in both dynamic and static balance. CONCLUSIONS: These results indicate that long term training resulted in an improvement both static and dynamic balance. Training can be suggested for patients with balance problems.


Assuntos
Modalidades de Fisioterapia , Equilíbrio Postural , Adolescente , Exercício Físico , Feminino , Humanos , Perna (Membro)/fisiologia , Movimento , Adulto Jovem
6.
J Cosmet Laser Ther ; 16(2): 104-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24410656

RESUMO

Laser hair removal is the most common procedure which is usually performed on patient's demands. Even though they are usually safe and well tolerated, with the widespread use both expected and unexpected side effects can be seen. Recognizing the source of side effects is an important issue for the laser operator. In recent years, a new laser technology has been introduced to aid in pain and other side effects in laser applications. Diode laser systems are produced for this technology. The major disadvantage with this laser is the gel application during procedure. We herein report a women while on her second session for laser hair-removal procedure with a 808-nm diode laser, complicated with an epidermal burn reaction due to accumulated debris on the guide.


Assuntos
Queimaduras/etiologia , Géis/efeitos adversos , Remoção de Cabelo/efeitos adversos , Remoção de Cabelo/métodos , Lasers Semicondutores/efeitos adversos , Terapia com Luz de Baixa Intensidade/efeitos adversos , Adulto , Técnicas Cosméticas , Feminino , Géis/uso terapêutico , Humanos , Lasers Semicondutores/uso terapêutico , Terapia com Luz de Baixa Intensidade/métodos
7.
Reprod Toxicol ; 123: 108519, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38043629

RESUMO

The placenta is a unique organ with an active metabolism and dynamically changing physiology throughout pregnancy. It is difficult to elucidate the structure of cell-cell and cell-extracellular matrix interactions of the placenta in in vivo studies due to interspecies differences and ethical constraints. In this study, human umbilical cord vein cells (HUVEC) and human placental choriocarcinoma cells (BeWo) were co-cultured for the first time to form spheroids (microtissues) on a three-dimensional (3D) Petri Dish® mold and compared with a traditional two-dimensional (2D) system. Vortioxetine is an antidepressant with a lack of literature on its use in pregnancy in established cultures, the toxicity of vortioxetine was studied to investigate the response of spheroids representing placental tissue. Spheroids were characterised by morphology and exposed to vortioxetine. Cell viability and barrier integrity were then measured. Intercellular junctions and the localisation of serotonin transporter (SERT) proteins were demonstrated by immunofluorescence (IF) staining in BeWo cells. Human chorionic gonadotropin (beta-hCG) hormone levels were also measured. In the 3D system, cell viability and hormone production were higher than in the 2D system. It was observed that the barrier structure was impaired, the structure of intracellular skeletal elements was altered and SERT expression decreased depending on vortioxetine exposure. These results demonstrate that the multicellular microtissue placenta model can be used to obtain results that more closely resemble in vivo toxicity studies of various xenobiotics than other 2D and mono-culture spheroid models in the literature. It also describes the use of 3D models for soft tissues other than the placenta.


Assuntos
Antidepressivos , Placenta , Gravidez , Feminino , Humanos , Placenta/metabolismo , Vortioxetina/toxicidade , Vortioxetina/metabolismo , Antidepressivos/toxicidade , Técnicas de Cocultura , Hormônios/metabolismo
8.
bioRxiv ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38948784

RESUMO

Mitochondrial creatine kinases are key players in maintaining energy homeostasis in cells by working in conjunction with cytosolic creatine kinases for energy transport from mitochondria to cytoplasm. High levels of MtCK observed in Her2+ breast cancer and inhibition of breast cancer cell growth by substrate analog, cyclocreatine, indicate dependence of cancer cells on the 'energy shuttle' for cell growth and survival. Hence, understanding the key mechanistic features of creatine kinases and their inhibition plays an important role in the development of cancer therapeutics. Herein, we present the mutational and structural investigation on understudied ubiquitous mitochondrial creatine kinase (uMtCK). Our cryo-EM structures and biochemical data on uMtCK showed closure of the loop comprising residue His61 is specific to and relies on creatine binding and the reaction mechanism of phosphoryl transfer depends on electrostatics in the active site. In addition, the previously identified covalent inhibitor CKi showed inhibition in breast cancer BT474 cells, however our biochemical and structural data indicated that CKi is not a potent inhibitor for breast cancer due to strong dependency on the covalent link formation and inability to induce conformational changes upon binding.

9.
Ginekol Pol ; 94(6): 463-469, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36861897

RESUMO

OBJECTIVES: The aim of this study is to evaluate the place of serum soluble L1 cell adhesion molecule (sL1CAM) level in the diagnosis of endometrial cancer and its relationship with clinicopathological features. MATERIAL AND METHODS: This cross-sectional study was performed with 146 patients who underwent endometrial biopsy and whose pathology results were reported as benign endometrial changes (n = 30), endometrial hyperplasia (n = 32) or endometrial cancer (n = 84). The sL1CAM level between the groups was compared. The relationship between clinicopathological features and serum sL1CAM was evaluated in patients with endometrial cancer. RESULTS: The mean serum sL1CAM level in patients with endometrial cancer was significantly higher than in patients without cancer. The sL1CAM value was statistically significantly higher in the group with endometrial cancer, than the group with endometrial hyperplasia (p < 0.001) and the group with benign endometrial changes (p < 0.001). There was no statistically significant difference in terms of sL1CAM between the group of patients with endometrial hyperplasia and the group of patients with benign endometrial changes (p = 0.954). sL1CAM value in type 2 endometrial cancer was statistically significantly higher than Type1 (p = 0.019). High sL1CAM level in patients with type 1 cancer was associated with poor clinicopathological features. However, no correlation was observed between clinicopathological features and serum sL1CAM level in type 2 endometrial cancers. CONCLUSIONS: Serum sL1CAM may be an important marker for evaluating the diagnosis and prognosis of endometrial cancer in the future. There may be a relationship between increased serum sL1CAM level in type 1 endometrial cancers and poor clinicopathological features.


Assuntos
Hiperplasia Endometrial , Neoplasias do Endométrio , Molécula L1 de Adesão de Célula Nervosa , Feminino , Humanos , Molécula L1 de Adesão de Célula Nervosa/metabolismo , Hiperplasia Endometrial/diagnóstico , Estudos Transversais , Biomarcadores Tumorais , Neoplasias do Endométrio/metabolismo , Prognóstico
10.
Front Med (Lausanne) ; 9: 904373, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35865178

RESUMO

Objective: To evaluate microvasculature in pregnant women with and without cardiovascular risk factors. Design: Cross-sectional, observational study. Population: Women were recruited at the outpatient clinic for high risk prenatal care. Out of a total of 345 women assessed at first and/or second and/or third trimester, 169 women without and 176 with cardiovascular risk factors were included. Methods: Nailfold video capillaroscopy (NVC) measurements were performed at magnification of 200x at all fingers except thumbs. Images were stored for offline measurement of capillary density (CDe) and capillary diameters (CDi). Maternal anthropometrics, obstetric, and medical history were used for categorization in low and high cardiovascular risk. Comparison between groups and trimesters, with respect to pregnancy outcome, was performed using linear mixed model analysis. Results: Women with a high risk cardiovascular profile show higher CDe, regardless of pregnancy outcome. CDi drops during pregnancy, with lowest CDi in third trimester in patients with preeclampsia. Capillary bed (CB), as a composite of CDe and CDi, is stable during pregnancy in women with low risk cardiovascular profile. In women with high risk cardiovascular profile, CB drops from the first to the second trimester, regardless of pregnancy outcome. Only in women with pre-eclampsia, the CB is lower in the third trimester as compared to the first trimester.There is an inverse association between CDe and mean arterial pressure (MAP) in women with high cardiovascular risk and pre-eclampsia. Conclusion: Microcirculation is altered during the course of pregnancy and microcirculatory behavior is different in patients with low and high cardiovascular risk profile, as well as in patients with preeclampsia.

11.
Front Med (Lausanne) ; 9: 1049459, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37180731

RESUMO

[This corrects the article DOI: 10.3389/fmed.2022.904373.].

12.
J Hum Reprod Sci ; 15(1): 51-57, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35494204

RESUMO

Background: Intrauterine insemination (IUI) combined with controlled ovarian stimulation (COS) results in higher pregnancy rates. However, there is still no consensus on the optimal COS protocol. Aims: In the present study, we aimed to analyse the effects of COS protocols with different gonadotropin types on IUI outcomes. Study Setting and Design: This was a retrospective cohort study conducted at the infertility clinic of a University hospital, including 237 COS + IUI cycles. Materials and Methods: Eligible cycles were divided into three groups according to the type of gonadotropin used for COS; cycles with recombinant follicle-stimulating hormone (rFSH) (group 1, n = 36), highly purified FSH (HP-FSH) (group 2, n = 178) and highly purified menotropin (HP-hMG) (group 3, n = 23). Clinical pregnancy rate (CPR) and live birth rate (LBR) per cycle were compared between groups. Statistical Analysis Used: The Mann-Whitney U test and Kruskal-Wallis test were used to compare numerical variables. Dunn test was used for multiple comparisons. Results: The duration of stimulation and total gonadotropin dose were similar between the three groups (P > 0.05). The CPR was 16.7% in rFSH group, 9.6% in HP-FSH group and 13.0% in HP-hMG group. The LBR was 16.7% in rFSH group, 8.4% in HP-FSH group and 13.0% in HP-hMG group. Both CPR and LBR were comparable in all three groups (P > 0.05). Conclusions: Ovarian stimulation with rFSH, HP-FSH and HP-hMG show similar COS characteristics. Furthermore, these three gonadotropin protocols for COS + IUI yielded comparable CPR and LBR. These findings suggest that all three gonadotropin types (rFSH, HP-FSH, HP-hMG) are similarly effective in COS + IUI cycles.

13.
Eur J Obstet Gynecol Reprod Biol ; 260: 64-69, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33743359

RESUMO

Cantrell's pentalogy is a congenital multiple malformation consisting of midline supraumbilical thoraco-abdominal wall defects, anterior and pericardial diaphragm defects, lower sternum defects, ectopia cordis and various intracardiac anomalies. Complete pentalogy is very rare. Some additional anomalies may accompany pentalogy and there are cases in the literature where chromosomal anomalies and pentalogy are seen. Cases of Cantrell's pentalogy in twin pregnancies are rare. Twin pregnancies with Cantrell's pentalogy in both fetuses are one of the rarest cases in the literature. In this study, we presented a twin pregnancy case with Cantrell's pentalogy in both fetuses and we reviewed twin pregnancy cases in which Cantrell's pentalogy was seen in the literature. In our case, anomalies were found in both fetuses in the evaluation performed on a 32-year-old, gravida 2, para 1 woman with 10 weeks + 5 days monochorionic-monoamniotic twin pregnancy. The first fetus had ectopia cordis, cystic hygroma and increased nuchal thickness (4.6 mm), and the anterior abdominal wall was in contact with the amniotic band. The second fetus had ectopia cordis omphalocele, cystic hygroma, holoprosencephaly and a single lower extremity deficiency. Both fetuses were pre-diagnosed with Cantrell's pentalogy and the parents were informed about the adverse course of the fetuses. After the completion of the legal procedures, with the approval and decision of the parents, termination was made in the 11th week of pregnancy. External images of the fetuses confirmed the diagnosis. The family denied the autopsy procedure. When we review the literature, twin pregnancies complicated by Cantrell's pentalogy are divided into 3 groups: Group1- cases where one of the twins has completely normal phenotype and the other twin has Cantrell's pentalogy; Group2- cases where one of the twins has Cantrell's pentalogy and the other twin does not have the Cantrell's pentalogy but has several anomalies; Group3- cases where both fetuses have Cantrell's pentalogy. In conclusion, early diagnosis of twin pregnancy cases complicated by Cantrell's pentalogy and determination of all anomalies in both fetuses are very important in terms of obstetric management.


Assuntos
Cardiopatias Congênitas , Pentalogia de Cantrell , Adulto , Feminino , Feto , Humanos , Recém-Nascido , Pentalogia de Cantrell/diagnóstico por imagem , Gravidez , Gravidez de Gêmeos , Ultrassonografia Pré-Natal
14.
DNA Repair (Amst) ; 108: 103231, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34649144

RESUMO

The Base Excision Repair (BER) pathway is a highly conserved DNA repair system targeting chemical base modifications that arise from oxidation, deamination and alkylation reactions. BER features lesion-specific DNA glycosylases (DGs) which recognize and excise modified or inappropriate DNA bases to produce apurinic/apyrimidinic (AP) sites and coordinate AP-site hand-off to subsequent BER pathway enzymes. The DG superfamilies identified have evolved independently to cope with a wide variety of nucleobase chemical modifications. Most DG superfamilies recognize a distinct set of structurally related lesions. In contrast, the Helix-hairpin-Helix (HhH) DG superfamily has the remarkable ability to act upon structurally diverse sets of base modifications. The versatility in substrate recognition of the HhH-DG superfamily has been shaped by motif and domain acquisitions during evolution. In this paper, we review the structural features and catalytic mechanisms of the HhH-DG superfamily and draw a hypothetical reconstruction of the evolutionary path where these DGs developed diverse and unique enzymatic features.


Assuntos
DNA Glicosilases , DNA/metabolismo , Dano ao DNA , DNA Glicosilases/metabolismo , Reparo do DNA , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo
15.
J Gynecol Obstet Hum Reprod ; 50(2): 101982, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33221558

RESUMO

Low response of patients with diminished ovarian reserve to exogenous gonadotropins in controlled ovarian stimulation (COS) protocols is one of the important problems of reproductive endocrinology. Various treatment protocols have been developed in patients with diminished ovarian reserve (DOR) or poor ovarian response (POR). Recently, the addition of growth hormone (GH) to treatment protocols has been brought to the agenda in these patients. In this study, we aimed to investigate the effect of GH adjuvant treatment on intracytoplasmic sperm injection (ICSI) cycle results in patients with DOR or POR. This retrospective cohort study was carried out with patients who diagnosed as DOR or POR and underwent ICSI. The patients were divided into the groups according to whether GH was used. In this study, ongoing pregnancy rates and live birth rates were observed to be significantly higher in the group receiving GH compared to the control group. In addition, there was a significant increase in embryo quality in the group receiving GH. As a result, the addition of GH to COS protocols in DOR and POR patients may increase the ongoing pregnancy rate, live birth rate, embryo quality.


Assuntos
Fertilização in vitro , Hormônio do Crescimento Humano/uso terapêutico , Reserva Ovariana , Injeções de Esperma Intracitoplásmicas , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Transferência Embrionária , Feminino , Gonadotropinas/uso terapêutico , Humanos , Infertilidade Feminina/terapia , Nascido Vivo , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
16.
ACS Chem Biol ; 15(1): 93-102, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31829624

RESUMO

The adenine glycosylase MutY selectively initiates repair of OG:A lesions and, by comparison, avoids G:A mispairs. The ability to distinguish these closely related substrates relies on the C-terminal domain of MutY, which structurally resembles MutT. To understand the mechanism for substrate specificity, we crystallized MutY in complex with DNA containing G across from the high-affinity azaribose transition state analogue. Our structure shows that G is accommodated by the OG site and highlights the role of a serine residue in OG versus G discrimination. The functional significance of Ser308 and its neighboring residues was evaluated by mutational analysis, revealing the critical importance of a ß loop in the C-terminal domain for mutation suppression in cells, and biochemical performance in vitro. This loop comprising residues Phe307, Ser308, and His309 (Geobacillus stearothermophilus sequence positions) is conserved in MutY but absent in MutT and other DNA repair enzymes and may therefore serve as a MutY-specific target exploitable by chemical biological probes.


Assuntos
DNA Glicosilases/metabolismo , Reparo do DNA/efeitos dos fármacos , DNA/química , Reparo Gênico Alvo-Dirigido/métodos , Sequência de Aminoácidos , Pareamento Incorreto de Bases , Domínio Catalítico , Guanina/química , Cinética , Conformação Molecular , Relação Estrutura-Atividade , Especificidade por Substrato
17.
J Immigr Minor Health ; 20(3): 529-535, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29204726

RESUMO

More than half of the 2.7 million registered Syrian refugees in Turkey are under 18 years of age. This study investigates prevalence of psychopathology and associated risk factors in refugee children in Turkey. Of a total of 218 children aged 9-15 years, 56.2% lost someone important to them, 55.1% saw dead or wounded people, 70.4% witnessed explosions or gun battles, 42.5% witnessed people being tortured and 25.6% personally experienced cruelty/torture during war. Prevalence of PTSD was 18.3% and that of anxiety-related disorders were as high as 69.0%. Death of an important person (p = .032) and male gender (p = .040) were associated with PTSD; whilst exposure to cruelty or torture (p = .014) and increasing duration of refuge (p = .042) were significantly associated with development of anxiety disorders. Findings of the present study reveals existence of the expected but unspoken mental health needs among the Syrian children in Turkey.


Assuntos
Transtornos Mentais/epidemiologia , Refugiados/psicologia , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Saúde Mental , Fatores de Risco , Autorrelato , Transtornos de Estresse Pós-Traumáticos , Síria , Turquia/epidemiologia
18.
J Biomed Mater Res A ; 105(6): 1656-1665, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28205372

RESUMO

Considerable research efforts have been devoted to zein-based biomaterials for tissue engineering and other biomedical applications over the past decade. The attention given to zein-based polymers is primarily attributed to their biocompatibility and biodegradability. However, due to the relatively low mechanical properties of these polymers, numerous inorganic compounds (e.g., hydroxyapatite, calcium phosphate, bioactive glasses, natural clays) have been considered in combination with zein to create composite materials in an attempt to enhance zein mechanical properties. Inorganic phases also positively impact on the hydrophilic properties of zein matrices inducing a suitable environment for cell attachment, spreading, and proliferation. This review covers available literature on zein and zein-based composite materials, with focus on the combination of zein with commonly used inorganic fillers for tissue engineering and drug delivery applications. An overview of the most recent advances in fabrication techniques for zein-based composites is presented and key applications areas and future developments in the field are highlighted. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1656-1665, 2017.


Assuntos
Materiais Biocompatíveis/química , Zeína/química , Silicatos de Alumínio/química , Animais , Fosfatos de Cálcio/química , Argila , Sistemas de Liberação de Medicamentos/métodos , Durapatita/química , Vidro/química , Humanos , Cerâmicas Modificadas Organicamente/química , Engenharia Tecidual/métodos
19.
Materials (Basel) ; 9(11)2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28774008

RESUMO

Hydrogel optimisation for biofabrication considering shape stability/mechanical properties and cell response is challenging. One approach to tackle this issue is to combine different additive manufacturing techniques, e.g., hot-melt extruded thermoplastics together with bioplotted cell loaded hydrogels in a sequential plotting process. This method enables the fabrication of 3D constructs mechanically supported by the thermoplastic structure and biologically functionalised by the hydrogel phase. In this study, polycaprolactone (PCL) and polyethylene glycol (PEG) blend (PCL-PEG) together with alginate dialdehyde gelatine hydrogel (ADA-GEL) loaded with stromal cell line (ST2) were investigated. PCL-PEG blends were evaluated concerning plotting properties to fabricate 3D scaffolds, namely miscibility, wetting behaviour and in terms of cell response. Scaffolds were characterised considering pore size, porosity, strut width, degradation behaviour and mechanical stability. Blends showed improved hydrophilicity and cell response with PEG blending increasing the degradation and decreasing the mechanical properties of the scaffolds. Hybrid constructs with PCL-PEG blend and ADA-GEL were fabricated. Cell viability, distribution, morphology and interaction of cells with the support structure were analysed. Increased degradation of the thermoplastic support structure and proliferation of the cells not only in the hydrogel, but also on the thermoplastic phase, indicates the potential of this novel material combination for biofabricating 3D tissue engineering scaffolds.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA