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A quantum ruler for orbital magnetism in moiré quantum matter. Science 2023; 382:81-87. [PMID: 37797004 DOI: 10.1126/science.adf2040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 08/30/2023] [Indexed: 10/07/2023]
Abstract
For almost a century, magnetic oscillations have been a powerful "quantum ruler" for measuring Fermi surface topology. In this study, we used Landau-level spectroscopy to unravel the energy-resolved valley-contrasting orbital magnetism and large orbital magnetic susceptibility that contribute to the energies of Landau levels of twisted double-bilayer graphene. These orbital magnetism effects led to substantial deviations from the standard Onsager relation, which manifested as a breakdown in scaling of Landau-level orbits. These substantial magnetic responses emerged from the nontrivial quantum geometry of the electronic structure and the large length scale of the moiré lattice potential. Going beyond traditional measurements, Landau-level spectroscopy performed with a scanning tunneling microscope offers a complete quantum ruler that resolves the full energy dependence of orbital magnetic properties in moiré quantum matter.
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Cornelia de Lange Syndrome Presenting as Hydrops Fetalis due to Intestinal Atresia. KLINISCHE PADIATRIE 2023. [PMID: 37494590 DOI: 10.1055/a-2099-3386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/28/2023]
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Evaluation of the effectiveness of systemic inflammatory indices in the diagnosis of respiratory distress syndrome in preterm with gestational age of ≤32 weeks. Am J Perinatol 2023. [PMID: 36898408 DOI: 10.1055/a-2051-8544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
OBJECTIVE It is not yet known whether systemic inflammatory indices affect the development of respiratory distress syndrome (RDS) in premature infants. We aimed to evaluate the relationship between systemic inflammatory indices obtained on the first day of life and the development of RDS in premature infants. STUDY DESIGN Premature infants with gestational age of ≤32 weeks were included in the study. Six systemic inflammatory indices involving neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), systemic immune-inflammation index (SII), pan-immune-inflammation value (PIV), and systemic inflammation response index (SIRI) were measured in the first 1 hours after birth and compared in premature infants with and without RDS. RESULTS A total of 931 premature infants, 579 infants in the RDS group and 352 infants in the non-RDS group, were included in the study. MLR, PLR, and SIRI values were similar between groups (p>0.05 for all parameters). NLR, PIV, and SII values in the RDS group were significantly higher than in the non-RDS group (p=0.005, p=0.011, and p<0.001, respectively). In the predictivity of RDS, the AUC value of SII was 0.842 and the cut-off value was ≥78.200. Multiple logistic analysis showed that a higher level of SII (≥78.2) was independently associated with RDS (OR 3.03, 95% CI 1.761-5.301). CONCLUSION Our results demostrated that a higher SII level (≥78.2) may be a predictor for the development of RDS in premature infants with gestational age of ≤32 weeks.
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Hemoglobin/Red Cell Distribution width Ratio (HRR): A Novel and Promising Red Cell Parameter in Ductal Closure. Arq Bras Cardiol 2023; 120:e20220339. [PMID: 36856242 PMCID: PMC10263456 DOI: 10.36660/abc.20220339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 09/23/2022] [Accepted: 11/16/2022] [Indexed: 02/16/2023] Open
Abstract
BACKGROUND It is still unclear how effective hematological parameters are in the closure of patent ductus arteriosus (PDA). OBJECTIVES The primary aim of our study is to investigate the effect of hemoglobin (HB)-to-red cell distribution width (RDW) ratio (HRR) on the closure of PDA. METHODS Premature babies with very low birth weight (VLBW: <1500 g) and <32 gestational weeks were included in the study, and all data were recorded retrospectively. Demographic characteristics, clinical results, red cell parameters, and HRR and their ratios were compared between hemodynamically significant PDA (hsPDA) and non-hsPDA groups. All results were statically analyzed, and P<0.05 was considered statistically significant. RESULTS A total of 677 premature babies, 269 in the hsPDA group and 408 in the non-hsPDA group, were included in the study. Hemoglobin (HB), hematocrit (HCT), mean cell volume (MCV), red blood cell (RBC), red cell distribution width (RDW), mean platelet volume (MPV), MCV/RBC ratio, HB/RBC ratio, RDW/RBC ratio, and RDW/MPV ratio were found to be similar between hsPDA and non-hsPDA groups, (p>0.05). HRR was found to be significantly lower in the hsPDA group [median (Quartile 1 (Q1) - Q3) (Q1 - Q3): 0.93 (0.8-1.0)] compared to non-hsPDA [median ( Q1 - Q3): 1.07 (1.0-1.2)] (p<0.001). The AUC for the diagnostic value of HRR in hsPDA was 0.816, and the cutoff value was ≤0.98 (p<0.001, 95% [CI]: 0.785-0.845, sensitivity: 90%, specificity: 92%). CONCLUSIONS HRR value was found to be both an effective and powerful parameter in diagnosing hsPDA.
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Role of Systemic Inflammatory Indices in the Prediction of Moderate to Severe Bronchopulmonary Dysplasia in Preterm Infants. Arch Bronconeumol 2023; 59:216-222. [PMID: 36681603 DOI: 10.1016/j.arbres.2023.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/02/2023] [Accepted: 01/03/2023] [Indexed: 01/09/2023]
Abstract
INTRODUCTION The role of systemic inflammatory indices in the diagnosis of bronchopulmonary dysplasia (BPD) is unknown. The aim of the study was to determine the possible clinical utility of systemic inflammatory indices in the prediction of moderate to severe BPD. METHODS Premature infants<32 weeks of gestational age were included in the study. Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), systemic immune-inflammation index (SII), pan-immune-inflammation value (PIV), and systemic inflammation response index (SIRI) were calculated at birth and at the time of diagnosis of BPD (at 36th weeks of postmenstrual age). The patients were divided into two groups as no or mild BPD and moderate or severe BPD. RESULTS A total of 1146 infants were included in the study, 957 in Group 1 and 189 in Group 2. The SIRI value was significantly higher in moderate or severe BPD both at birth and at the 36th week of postmenstrual age (p<0.001 and p<0.001, respectively). The AUC value of SIRI was 0.809 and the cut-off value was>0.98 in the predictivity of BPD at birth. The AUC value of SIRI was 0.842 and the cut-off value was>1.33 for the diagnosis of BPD at 36th week of postmenstrual age. After multiple logistic regression analysis, SIRI was shown to be a significant parameter for the diagnosis of BPD (OR 2.847, 95% CI 1.557-4.875). CONCLUSIONS SIRI may be a useful biomarker for predicting moderate to severe BPD and a marker of clinical importance in the follow-up of infants with BPD.
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Intravenous Immunoglobulin Use in Hemolytic Disease Due to ABO Incompatibility to Prevent Exchange Transfusion. Front Pediatr 2022; 10:864609. [PMID: 35573949 PMCID: PMC9095978 DOI: 10.3389/fped.2022.864609] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 03/21/2022] [Indexed: 11/10/2022] Open
Abstract
INTRODUCTION Intravenous immunoglobulin (IVIG) has been widely used to treat the hemolytic disease of the newborn (HDN). Although it has been shown that IVIG treatment reduces the duration of phototherapy and hospitalization, the use of IVIG in hemolytic disease due to ABO incompatibility has been controversial in recent years. This study aimed to investigate the role of IVIG in the prevention of exchange transfusion in infants with ABO HDN who presented with bilirubin levels at or above the level of exchange transfusion. MATERIALS AND METHODS This study evaluated the data of infants with ABO HDN in the Turkish Neonatal Jaundice Online Registry. The infants with ABO HDN who met the total serum bilirubin level inclusion criteria (within 2-3 mg/dL of exchange transfusion or even above exchange transfusion level) were included in the study according to the guidelines from the American Academy of Pediatrics and the Turkish Neonatal Society. All patients were managed according to the unit protocols recommended by these guidelines and received light-emitting diode (LED) phototherapy. Infants who only received LED phototherapy, and who received one dose of IVIG with LED phototherapy were compared. RESULTS During the study period, 531 term infants were included in the study according to inclusion criteria. There were 408 cases in the phototherapy-only group, and 123 cases in the IVIG group. The demographic findings and the mean bilirubin and reticulocyte levels at admission were similar between the groups (p > 0.05), whereas the mean hemoglobin level was slightly lower in the IVIG group (p = 0.037). The mean age at admission was earlier, the need for exchange transfusion was higher, and the duration of phototherapy was longer in the IVIG group (p < 0.001, p = 0.001, and p < 0.001, respectively). The rate of re-hospitalization and acute bilirubin encephalopathy (ABE) was higher in the IVIG group (p < 0.001 and p = 0.01, respectively). CONCLUSION In this study, we determined that one dose of IVIG did not prevent an exchange transfusion nor decrease the duration of phototherapy in infants, who had bilirubin levels near or at exchange transfusion level, with hemolytic disease due to ABO incompatibility.
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Excessive screen time and lower psychosocial well-being among preschool children. Arch Pediatr 2021; 29:61-66. [PMID: 34758931 DOI: 10.1016/j.arcped.2021.10.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 06/02/2021] [Accepted: 10/03/2021] [Indexed: 12/23/2022]
Abstract
OBJECTIVE Too much screen time is a common and severe threat to child health and excessive screen exposure exists in the early childhood population in Turkey. We aimed to investigate the associations between excessive screen time and psychosocial well-being in a sample of Turkish preschool children. METHODS Mothers and their healthy children aged 2-5 years who applied to general pediatric outpatient clinics for well-child examinations were enrolled in this descriptive cross-sectional study. Children with a daily screen time of less than 1 h (low) or more than or equal to 4 h (excessive) were included. Psychosocial well-being was assessed using the parent version of the Strengths and Difficulties Questionnaire. RESULTS In all, 220 mother-child pairs participated in this study. Emotional symptoms, conduct problems, peer relationship problems, and total difficulties scores were significantly higher in the children with excessive screen time (p<0.05), while the hyperactivity-inattention and prosocial scores were not different between the low and excessive screen time groups (p>0.05). After adjusting for potential confounders, the children with excessive screen time had significantly increased odds ratios for having conduct and peer relationship problems (OR [95% CI]: 2.62 [1.11-6.19], p = 0.028 and 2.57 [1.25-5.26], p = 0.010, respectively). CONCLUSION Turkish preschool children with excessive screen time were significantly more likely to have poor psychosocial well-being. Preschool children with behavioral problems should be evaluated for excessive screen time.
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Single Center Results With SRS And FSRT In Uveal Melanoma. Int J Radiat Oncol Biol Phys 2020. [DOI: 10.1016/j.ijrobp.2020.07.109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Paraurethral cyst in a newborn. ACTA ACUST UNITED AC 2020; 92. [PMID: 32597124 DOI: 10.4081/aiua.2020.2.162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 01/31/2020] [Indexed: 11/23/2022]
Abstract
Paraurethral cysts are rare and occur with obstruction of the Skene duct. In this case, we aimed to present a paraurethral cyst in a baby girl. A 4-day-old newborn was consulted for pediatric urology because of an interlabial mass. In genital examination, a noninvasive mass measuring 2 × 1.5 cm was observed in the interlabial region, and the introitus was completely closed. Ultrasonography showed a cystic lesion localized on the right side of the urethra with a smoothly contoured, thin-walled, hypoechoic structure. The patient underwent puncture under sterile conditions. The content of the mass was mucoid and clear fluid. Paraurethral cysts are often asymptomatic and benign. There is no definitive consensus on treatment.
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Effect of diazepam, sertraline and melatonin on the stress-induced reproductive disorders and intrauterine growth restriction in female rats. J Matern Fetal Neonatal Med 2019; 34:4103-4109. [PMID: 31875735 DOI: 10.1080/14767058.2019.1706469] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Objective: Psychological stress is an important factor triggering depression and anxiety. Infertility is known to cause stress; however, it is not clearly known whether stress causes infertility as well. In addition, there are different opinions accounting for the relation of stress-induced oxidative stress to infertility and intrauterine growth restriction. The aim of the study is to examine the effect of sertraline, diazepam and melatonin on the infertility, intrauterine growth restriction and oxidative stress that can be caused by forced immobilization stress management (FISM) in female rats.Materials and methods: Wistar rats were grouped as healthy rats (HG) applied distilled water, stress treated control group (SC), and 20 mg/kg sertraline + stress (SS), 2 mg/kg diazepam + stress (DS) and 10 mg/kg melatonin + stress (MS) treated rats. The medicines were administered orally once a day for 30 days. At the end of this period, oxidant/antioxidant parameters were measured through the blood samples collected from the tail veins of all rats. Then the rats were kept in a suitable environment for 2 months for breeding.Results: FISM caused oxidative stress in blood serum of animals, infertility and intrauterine growth restriction (decrease in birth weight of the baby). Best medicines to suppress FISM-related oxidative stress are melatonin > diazepam > sertraline respectively, while sertraline > diazepam > melatonin were most successful in terms of preventing infertility. The best medicines preventing the FISM-caused intrauterine growth restriction were found to be melatonin > diazepam > sertraline, respectively.Conclusion: FISM causes oxidative stress in animals. Oxidative stress is understood to affect the intrauterine growth negatively although it is not a major component in the pathogenesis of infertility. While melatonin is only effective in preventing the oxidative stress-related intrauterine growth restriction, antidepressants and anxiolytic treatment were found to be helpful in preventing both infertility and intrauterine growth restriction.
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Systemic Pseudohypoaldosteronism Type 1 due to 3 Novel Mutations in SCNN1Aand SCNN1BGenes. Horm Res Paediatr 2019; 91:175-185. [PMID: 31018202 DOI: 10.1159/000498860] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Accepted: 02/12/2019] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE The systemic form of pseudohypoaldosteronism type 1 (PHA1) is an autosomal recessive disorder characterized by defective sodium transport in multi-organ systems. Mutations in the genes encoding the amiloride-sensitive epithelial sodium channel, ENaC, account for genetic causes of systemic PHA1. We describe systemic PHA1 due to 4 novel variants detected in SCNN1A and SCNN1B in 3 cases from 3 unrelated consanguineous families. PATIENTS AND METHODS We evaluated the clinical presentations, biochemical and hormonal characteristics, and molecular genetic analysis results of 3 patients from 3 unrelated consanguineous families and parents from whom samples were available. RESULTS The ages at presentation were postnatal days 9, 10, and 5. The main presentation symptoms were vomiting, poor feeding, weakness, weight loss, and skin rash. All patients exhibited laboratory characteristics including severe hyponatremia, hyperkalemia, metabolic acidosis, elevated plasma renin, elevated aldosterone, and positive sweat tests, suggesting a diagnosis of systemic PHA1. Molecular genetic analysis revealed 2 novel pathogenic variants [c.87C>A(p.Tyr29*)/IVS9 + 1G>A (c.1346 + 1G>A)] in SCNN1Bin case 1, a novel homozygous pathogenic variant [p.His69Arg(c.206A>G] in SCNN1Ain case 2, and a homozygous one-base duplication, p.A200Gfs*6 (c.598dupG), in SCNN1A in case 3. CONCLUSION PHA1 should be considered at differential diagnosis in patients presenting with hyponatremia, hyperkalemia, and metabolic acidosis. The cases in this report involving 4 novel variants will add valuable insights into the phenotype-genotype relationship and will expand the mutation database.
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A Comparative Trial of the Effectiveness of Nasal Interfaces Used to Deliver Continuous Positive Airway Pressure for a Brief Period in Infants With Transient Tachypnea of the Newborn. Arch Bronconeumol 2019; 56:373-379. [PMID: 31740083 DOI: 10.1016/j.arbres.2019.07.027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Revised: 07/09/2019] [Accepted: 07/29/2019] [Indexed: 11/19/2022]
Abstract
INTRODUCTION There is insufficient data on the effectiveness of the interfaces used for nasal continuous airway pressure (nCPAP) in newborn infants. Transpulmonary pressure (PTP) calculated from a measured esophageal pressure (Pes) could be used as a surrogate for the pressure transmitted to the distal airways during nCPAP. We aimed to compare the effectiveness of two nasal interfaces, the nasal mask and bi-nasal short prongs, during a relatively brief period of respiratory support by calculated PTP (cPTP) in infants with transient tachypnea of the newborn (TTN). METHODS Newborns with TTN who needed respiratory assistance with nCPAP were randomized to use either bi-nasal short prongs or a nasal mask. Esophageal pressure measurements were done in order to calculate PTP with either interface. The primary outcome was the cPTP transmitted with each nasal interface. Esophageal pressure measurements were recorded and PTP values were calculated from Pes measurements at the 1st, 6th, 12th and 24th hours in each patient as long as the respiratory support lasted. RESULTS Sixty-two newborns with TTN and on nCPAP were randomized into two groups: Group 1 to use bi-nasal short prongs (n: 31) and Group 2 to use a nasal mask (n: 31). Inspiratory and expiratory Pes and cPTP values at the 1st, 6th, 12th and 24th hours were similar with the two interfaces (P<.05). CONCLUSIONS A nasal mask is similarly effective and safe as bi-nasal short prongs during a brief period of non-invasive respiratory support with nCPAP in late preterm and term neonates with TTN.
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Mechanical dissipation via image potential states on a topological insulator surface. NATURE MATERIALS 2019; 18:1201-1206. [PMID: 31611672 DOI: 10.1038/s41563-019-0492-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 08/27/2019] [Indexed: 06/10/2023]
Abstract
Joule energy loss due to resistive heating is omnipresent in today's electronic devices whereas quantum-mechanical dissipation is largely unexplored. Here, we experimentally observe a suppression of the Joule dissipation in Bi2Te3 due to topologically protected surface states. Instead, a different type of dissipation mechanism is observed by pendulum atomic force microscopy, which is related to single-electron tunnelling resonances into image potential states that are slightly above the Bi2Te3 surface. The application of a magnetic field leads to the breakdown of the topological protection of the surface states and restores the expected Joule dissipation process. Nanomechanical energy dissipation experienced by the cantilever of the pendulum atomic force microscope provides a rich source of information on the dissipative nature of the quantum-tunnelling phenomena on the topological insulator surface, with implications for coupling a mechanical oscillator to the generic quantum material.
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Placenta, Secret Witness of Infant Morbidities: The Relationship Between Placental Histology and Outcome of the Premature Infant. Turk Patoloji Derg 2019; 35:28-35. [PMID: 30614512 DOI: 10.5146/tjpath.2018.01443] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE The microscopic and macroscopic features of the placenta can contribute to the clinical understanding of premature delivery. The aim of our study was to figure out the relationship between the histopathological findings of the placentas of premature deliveries and its effects on neonatal morbidity and mortality. MATERIAL AND METHOD The placentas of 284 singleton preterm infants with < 35 weeks of gestation were examined. Three groups were created as the normal, chorioamnionitis and vasculopathy groups according to the histopathological findings in the placentas of the subjects. RESULTS The mean gestational age of the infants in the study group was 30.5 ± 3.2 weeks, and the mean birth weight was 1588 ± 581 g. The pathology was normal in ninety-six (33.8%), vasculopathy in 153 (53.9%) and chorioamnionitis in 35 (12.3%). The gestation age of the infants was lower in the chorioamnionitis group. Moreover, retinopathy of prematurity, early onset neonatal sepsis, and duration of respiratory support were found to be higher in the chorioamnionitis group. In the vasculopathy group, preeclampsia and small for gestational age were found to be significantly higher. CONCLUSION Histopathological findings of the placentas from preterm deliveries provided important data in determining the etiology of preterm delivery and outcomes of infants. Infants delivered by mothers with chorioamnionitis were particularly found to be more preterm, and these preterm infants would have a longer hospital stay, higher respiratory support requirement, and more serious morbidities.
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Health care-associated infection surveillance: A prospective study of a tertiary neonatal intensive care unit. J Infect Dev Ctries 2019; 13:181-187. [PMID: 32040446 DOI: 10.3855/jidc.10688] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 10/25/2018] [Indexed: 10/31/2022] Open
Abstract
INTRODUCTION Health care-associated infection (HCAI) is a serious problem of neonatal intensive care units (NICUs) which is related to morbidity, mortality and increased cost of medical care. This study aimed to determine the incidence of HCAI in a tertiary NICU and identify the risk factors. METHODOLOGY This prospective cohort study was conducted between July 1, 2011 and June 30, 2012. All newborns admitted to the NICU except for those who died or were discharged within 48 hours after admission were included. The definitions of Centers for Disease Control and Prevention (CDC) were used to diagnose specific types of infections. The incidence, causative organisms, risk factors and mortality of HCAIs were evaluated. RESULTS Among 352 newborns, a total of 60 HCAI episodes were evaluated in 37 (10.5%) of the patients over 5,212 patient-days. The overall incidence of HCAI was 17%, and the rate was 11.5/1,000 patient-days. Blood stream infection (BSI) was the most common HCAI (n = 42, 70%). In a multivariable logistic regression analysis, the presence of a central venous catheter/umbilical catheter (CVC/UC), the presence of a urinary catheter, and gestational age (< 32 weeks of gestation) were identified as significant independent risk factors. Gram-negative pathogens were the most common isolates. The overall mortality rate was 4%. The HCAI-related mortality rate was 10.8%. CONCLUSIONS Patient care quality can be improved with surveillance of HCAI. The incidence and rate of HCAI in our NICU were found to be higher than international reports with a direct impact on mortality of preterm infants.
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SUN-P257: Evaluation of Educational Efficiency Based on Orem’s Self-Care Theory Given to Parents of Children with Gastrostomy. Clin Nutr 2017. [DOI: 10.1016/s0261-5614(17)30372-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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P-004 Immunohistochemical Expression of LRG5 and CD44 in Colorectal Polyps and Adenocarcinomas: Implications for Carcinogenesis. Ann Oncol 2016. [DOI: 10.1093/annonc/mdw199.04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Impact of Prophylactic Continuous Positive Airway Pressure on Transient Tachypnea of the Newborn and Neonatal Intensive Care Admission in Newborns Delivered by Elective Cesarean Section. Am J Perinatol 2016; 33:99-106. [PMID: 26295966 DOI: 10.1055/s-0035-1560041] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
OBJECTIVE This study aims to evaluate the effect of the prophylactic continuous positive airway pressure (CPAP) administration in the delivery room to newborns who were delivered by elective cesarean section (CS). STUDY DESIGN Inborn infants with gestational age between 34(0/7) to 38(6/7) and born by elective CS were prospectively randomized to receive either prophylactic CPAP for 20 minutes via face mask or standardized care without CPAP in the delivery room. Primary outcomes were the incidence of transient tachypnea of the newborn (TTN) and neonatal intensive care unit (NICU) admission due to respiratory distress. RESULTS A total of 259 infants with a mean gestational age of 37.7 ± 0.8 weeks and birth weight of 3,244 ± 477 g were included. A total of 134 infants received prophylactic CPAP and 125 received control standard care. The rate of NICU admission was significantly lower in prophylactic CPAP group (p = 0.045). Although the rate of TTN was lower in the prophylactic CPAP group, the difference was not statistically significant (p = 0.059). The rate of NICU admission due to respiratory distress was significantly higher in late-preterm cohort than early-term cohort (p < 0.0001). CONCLUSION Prophylactic CPAP administration decreases the rate of NICU admission without any side effect in late-preterm and early-term infants delivered by elective CS.
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Extra-lobar Pulmonary Sequestration Requiring Intrauterine Thoracentesis. APSP J Case Rep 2015; 6:3. [PMID: 25628992 PMCID: PMC4288834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 07/21/2014] [Indexed: 12/02/2022] Open
Abstract
Congenital lung malformations can result in significant morbidity and mortality in children. Pulmonary sequestration is an uncommon congenital malformation of the lung that can cause complications even in fetal life. We herein present a newborn with extra-lobar sequestration (ELS) that lead to hydrops fetalis necessitating fetal intervention.
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Efficacy and safety of intravenous colistin in preterm infants with nosocomial sepsis caused by Acinetobacter baumannii. Am J Perinatol 2014; 31:1079-86. [PMID: 24584997 DOI: 10.1055/s-0034-1371361] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
OBJECTIVES To describe the efficacy of intravenous colistin on clinical and microbiological outcomes in preterm infants with nosocomial sepsis in neonatal intensive care unit (NICU) and define adverse events observed with this treatment. METHODS The records of preterm infants who received colistin with or without positive cultures in the NICU were retrospectively reviewed. Patients were evaluated for response to therapy and side effects. RESULTS A total of 21 preterm infants with medians of 28 weeks (23-36) gestational age and 870 g (620-2,650) birth weight were included. The median duration and dose of colistin therapy were 9 days (3-26) and 3 mg/kg/d (2-5). Recovery rate in patients including all with/without positive culture was 81% (17/21). Microbiological clearance by colistin was 69% (9/13). The major side effect observed was acute kidney injury (19%). At least 24% of infants required electrolyte supplementation during the colistin therapy. Magnesium levels were significantly lower at the end of the colistin therapy (p < 0.001). Acute kidney injury and electrolyte disturbances including hypomagnesemia were reversible in all surviving patients. CONCLUSION We suggest that renal function tests and serum electrolytes should be monitored closely and replaced in case of any need during the colistin therapy in preterm infants.
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International Nosocomial Infection Control Consortium (INICC) report, data summary of 43 countries for 2007-2012. Device-associated module. Am J Infect Control 2014; 42:942-56. [PMID: 25179325 DOI: 10.1016/j.ajic.2014.05.029] [Citation(s) in RCA: 172] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 05/07/2014] [Accepted: 05/07/2014] [Indexed: 12/14/2022]
Abstract
We report the results of an International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2007-December 2012 in 503 intensive care units (ICUs) in Latin America, Asia, Africa, and Europe. During the 6-year study using the Centers for Disease Control and Prevention's (CDC) U.S. National Healthcare Safety Network (NHSN) definitions for device-associated health care-associated infection (DA-HAI), we collected prospective data from 605,310 patients hospitalized in the INICC's ICUs for an aggregate of 3,338,396 days. Although device utilization in the INICC's ICUs was similar to that reported from ICUs in the U.S. in the CDC's NHSN, rates of device-associated nosocomial infection were higher in the ICUs of the INICC hospitals: the pooled rate of central line-associated bloodstream infection in the INICC's ICUs, 4.9 per 1,000 central line days, is nearly 5-fold higher than the 0.9 per 1,000 central line days reported from comparable U.S. ICUs. The overall rate of ventilator-associated pneumonia was also higher (16.8 vs 1.1 per 1,000 ventilator days) as was the rate of catheter-associated urinary tract infection (5.5 vs 1.3 per 1,000 catheter days). Frequencies of resistance of Pseudomonas isolates to amikacin (42.8% vs 10%) and imipenem (42.4% vs 26.1%) and Klebsiella pneumoniae isolates to ceftazidime (71.2% vs 28.8%) and imipenem (19.6% vs 12.8%) were also higher in the INICC's ICUs compared with the ICUs of the CDC's NHSN.
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AB1045 Development and Validation of Juvenile Autoinflammatory Disease Multidimensional Assessment Report (JAIMAR). Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2014-eular.5963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Congenital analbuminemia caused by a novel aberrant splicing in the albumin gene. Biochem Med (Zagreb) 2014; 24:151-8. [PMID: 24627724 PMCID: PMC3936982 DOI: 10.11613/bm.2014.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 12/10/2013] [Indexed: 12/25/2022] Open
Abstract
Introduction: Congenital analbuminemia is a rare autosomal recessive disorder manifested by the presence of a very low amount of circulating serum albumin. It is an allelic heterogeneous defect, caused by variety of mutations within the albumin gene in homozygous or compound heterozygous state. Herein we report the clinical and molecular characterization of a new case of congenital analbuminemia diagnosed in a female newborn of consanguineous (first degree cousins) parents from Ankara, Turkey, who presented with a low albumin concentration (< 8 g/L) and severe clinical symptoms. Materials and methods: The albumin gene of the index case was screened by single-strand conformation polymorphism, heteroduplex analysis, and direct DNA sequencing. The effect of the splicing mutation was evaluated by examining the cDNA obtained by reverse transcriptase - polymerase chain reaction (RT-PCR) from the albumin mRNA extracted from proband’s leukocytes. Results: DNA sequencing revealed that the proband is homozygous, and both parents are heterozygous, for a novel G>A transition at position c.1652+1, the first base of intron 12, which inactivates the strongly conserved GT dinucleotide at the 5′ splice site consensus sequence of this intron. The splicing defect results in the complete skipping of the preceding exon (exon 12) and in a frame-shift within exon 13 with a premature stop codon after the translation of three mutant amino acid residues. Conclusions: Our results confirm the clinical diagnosis of congenital analbuminemia in the proband and the inheritance of the trait and contribute to shed light on the molecular genetics of analbuminemia.
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The impact of evaluating platelet transfusion need by platelet mass index on reducing the unnecessary transfusions in newborns. J Matern Fetal Neonatal Med 2014; 27:1787-9. [DOI: 10.3109/14767058.2013.879708] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Erythema multiforme due to parainfluenza virus in a newborn: A case report and review of the literature. INDIAN JOURNAL OF PAEDIATRIC DERMATOLOGY 2014. [DOI: 10.4103/2319-7250.143663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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A novel mutation in the calcium sensing receptor gene in a neonate with severe hyperparathyroidism. GENETIC COUNSELING (GENEVA, SWITZERLAND) 2014; 25:331-335. [PMID: 25365856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
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An intention to achieve better postnatal in-hospital-growth for preterm infants: adjustable protein fortification of human milk. Early Hum Dev 2013; 89:1017-23. [PMID: 24035039 DOI: 10.1016/j.earlhumdev.2013.08.015] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 07/10/2013] [Accepted: 08/20/2013] [Indexed: 01/16/2023]
Abstract
OBJECTIVE We assessed the effect of human milk (HM) fortification with extra protein supplement by an adjustable protein fortification method according to the weekly blood urea nitrogen (BUN) levels on growth in hospitalized preterm infants. METHOD A prospective observational intervention study in 58 preterms born ≤32 weeks of gestation and fed with breast milk was conducted. Preterms who were given a commercial HM fortifier which provides an additional protein of 0.8 g/3 scales according to the standard feeding strategy served as a historical control group. Infants who were given extra protein in addition to the HM fortifier with another commercial protein supplement which provides an additional protein of 2.2g/1 scale comprised the intervention group. Additional protein supplementation was adjusted according to BUN levels weekly in the intervention group. Weight gain velocities (g/kg/day), length, head circumferences (HC) gain velocities (mm/day) and daily growth indexes for weight, height and HC (percentage per day) were calculated. RESULTS The median amount of daily enteral protein intake [4 (3.4-4.6) vs. 2.78 (2.1-3.1) g/kg/day, p < 0.0001] was significantly higher in the interventional group. Length (p = 0.008) and HC (p < 0.0001) gain velocities were significantly higher in the intervention group. Daily growth indexes for weight (2.2% vs. 1.8%, p = 0.026), for length (0.4% vs. 0.3%, p = 0.027) and for HC (0.48% vs. 0.36% per day, p = 0.003) were significantly higher in the intervention group. CONCLUSION A higher protein intake by adjustable protein fortification method without energy or volume change leads to improved postnatal in-hospital-growth in very low birth weight infants.
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PReS-FINAL-2210: Qualitative aspects of autoinflammatory diseases. Pediatr Rheumatol Online J 2013. [PMCID: PMC4043759 DOI: 10.1186/1546-0096-11-s2-p200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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PW02-023 - Qualitative aspects of autoinflammatory diseases. Pediatr Rheumatol Online J 2013. [PMCID: PMC3952222 DOI: 10.1186/1546-0096-11-s1-a163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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THU0473-HPR Living with childhood vasculitis; a qualitative study. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2012-eular.2438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Crigler-Najjar syndrome type I in a Turkish newborn caused by a novel mutation and Gilbert type genetic defect. GENETIC COUNSELING (GENEVA, SWITZERLAND) 2013; 24:273-277. [PMID: 24341141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Crigler-Najjar syndrome (CNS), caused by deficiency of bilirubin uridine diphosphate glucuronosyltransferase (UGT) 1A1, is a rare and autosomal recessive inherited disorder characterized by severe unconjugated nonhemolytic hyperbilirubinemia since birth. We present a girl with CNS type I caused by a novel mutation and Gilbert type genetic defect. Gilbert's Syndrome (GS) and CNS type I both involve abnormalities in bilirubin conjugation secondary to deficiency of bilirubin UGT. The combined defects even in benign genetic forms were shown to cause more serious clinical disease. The patient has been treated with daily home-based phototherapy for more than nine months and considered as a candidate for liver transplantation.
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EP-1381 DOSIMETRIC CONTROL OF THE TREATMENT PLANNING SYSTEM OF CYBERKNIFEÆ ROBOTIC RADIOLOGICAL SURGERY INSTRUMENT. Radiother Oncol 2012. [DOI: 10.1016/s0167-8140(12)71714-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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EP-1410 THE EVALUATION OF SECONDARY MALIGNANCY RISK DUE TO THE CRANIOSPINAL CT SIMULATION. Radiother Oncol 2012. [DOI: 10.1016/s0167-8140(12)71743-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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EP-1378 INVESTIGATING THE EFFECT OF DOSE RATE ON THE DURATION OF IMRT QA PROCEDURE. Radiother Oncol 2012. [DOI: 10.1016/s0167-8140(12)71711-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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4124 POSTER Robotic Stereotactic Radiotherapy in the Management of Pediatric Patients With Benign and Malign Lesions. Eur J Cancer 2011. [DOI: 10.1016/s0959-8049(11)71302-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Concomitant trastuzumab with thoracic radiotherapy: a morphological and functional study. Ann Oncol 2011; 22:1120-1126. [DOI: 10.1093/annonc/mdq590] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Abstract
This article describes the scanning electron microscopic (SEM) features of the ovine interdigital sinus. The lumen was filled with a dense secretory material and quite a number of hairs embedded in the luminal content. For SEM purposes, the sinus was divided into three parts: base, body and neck. At the cut surface, the wall exhibited significant folds which were almost absent in the base, the very short blind end of the sinus. The wall had three layers: epidermis, dermis and fibrous capsule. Stratified epithelium with a prominent keratin layer faced the lumen. The inner surface was similar to the skin surface; however, it was coarser due to folds. The fibrous capsule was composed mainly of dense connective tissue, constituting the outermost layer of the wall. The dermis contained common skin structures including sebaceous glands, hair follicles, arrector pili muscles and apocrine glands. Sebaceous glands appeared as groups of bubbles if they were not collapsed. Apocrine glands generally appeared as a group of coiled tubules. They frequently exhibited apocrine blebs, which is a feature of apocrine secretion. SEM was able to locate some secretory vesicles in the lumen of apocrine tubules which is frequently filled by secretory content. Thus, the apocrine tubules exhibited classical features of apocrine secretion.
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Dextrocardia is a component of left-sided Poland syndrome. J Thorac Cardiovasc Surg 2005; 130:1471-2. [PMID: 16256811 DOI: 10.1016/j.jtcvs.2005.06.048] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2005] [Accepted: 06/30/2005] [Indexed: 11/21/2022]
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Abstract
Bovine tactile hairs in skin samples from the lateral side of the upper lip were examined using scanning electron and light microscopy. The root of these hairs has a variable length and is surrounded by a large sinus located between the internal and the external dermal sheath. With a prominent thickness, the external dermal sheath forms the external wall of the tactile hair and contains many nerves some of which extend into trabeculae. Trabeculae projecting from the internal dermal sheath and attaching to the external dermal sheath with two or more branches are present in the entire sinus. The trabeculae are interconnected by connective tissue sheets that support the integrity of the trabecular organization. The sinus surfaces as well as trabeculae are lined by endothelia. As a result, the bovine tactile hair is truly a cavernous type of tactile hair with a well organized microscopic anatomy. Thus, the bovine tactile hair most likely plays an important role in relatively immobile and insensitive bovine lips.
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Abstract
Intramuscular lipoma (IML) is a relatively common variant of lipomas. The most important sites for IML are the large muscles of the extremities. Spindle cell lipoma (SCL) is a rare and distinct variant of lipoma. Most SCL arise in the neck, shoulders or back. It has also been described in unusual sites, such as the oral cavity, larynx, bronchus, breast, orbit and extremities. However, localization of a SCL in an IML has not been described yet. Thus, we present the first SCL located in an IML, which was localized underneath the fascia and embedded within the left sartorius muscle of a 55-year-old man. Microscopically, the SCL component of the tumor was sharply circumscribed by a fibrous capsule and clearly separated from the IML in which it was localized. The collagen-forming spindle cells of the SCL showed neither atypia nor pleomorphism. These cells stained positive for CD34, while the mature fat tissue component of the SCL was positive for S-100 protein and negative for CD34. Spindle cells were negative for S-100 protein. Vimentin stained both components of the SCL, as well as the striated muscle fibers and mature fat tissue of the IML. In conclusion, careful morphological observation along with immunohistochemistry for CD34 and S-100 protein are essential to differentiate this rare tumor from lesions that enter the differential diagnosis.
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Abstract
In this study, the chordae tendineae of 10 adult chickens have been investigated by means of scanning electron microscopy (SEM). It has been observed that the diameter of the collagen fibrils on the left side of the heart was greater than those on the right side. The present study has determined that only perichordal and interchordal ligaments are present in the chicken. It was also observed that axial tendons were surrounded by perichordal membrane. Although no difference was evident among the apex of the chordae, differences were observed between the base and apex of the same chordae.
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Abstract
Arterial vascularisation of the ovine pineal gland was investigated by latex injection preparations of the common carotid artery in 20 adult Akkaraman sheep brains under stereo light microscope. It was observed that the arterial supply comes exclusively from branches of the caudal cerebral artery. The pineal gland was found to contain a rich vascular network. This network also received a few branches from the caudal choroid rami.
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Vascularisation of the cerebellar nuclei in Akkaraman sheep. Acta Vet Hung 2003; 51:433-7. [PMID: 14680055 DOI: 10.1556/avet.51.2003.4.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This study reports an anatomical study of the vascular supply in 20 Akkaraman sheep cerebelli from adult subjects of both sexes. The origin and branching pattern of the cerebellar artery vascularising the cerebellar nuclei were studied by gross dissection and vascular injection. Then dissection was performed and vessels nourishing the cerebellar nuclei were documented. Four bilaterally symmetrical cerebellar nuclei were determined as nucleus lateralis cerebelli, nucleus interpositus lateralis cerebelli, and nucleus interpositus medialis cerebelli and nucleus fastigii from lateral to medial side. It has been previously confirmed that vascularisation of the cerebellar nuclei is carried out by intermediary branches of the rostral cerebellar artery and the caudal cerebellar artery. However, this study has confirmed that the caudal cerebellar artery has no contribution in the vascularisation of the cerebellar nuclei.
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Comparison of pure nicotine- and smokeless tobacco extract-induced toxicities and oxidative stress. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1999; 37:434-439. [PMID: 10508890 DOI: 10.1007/s002449900537] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The toxicities and oxidative stress-inducing actions of (-)-nicotine and smokeless tobacco extract (STE), containing equivalent amounts of nicotine, were studied. Toxicities were determined by colony formation assays using Chinese hamster ovary (CHO) cells. Results indicated that nicotine is less toxic than smokeless tobacco extract that contained the same amount of nicotine. The generation of reactive oxygen species, following treatment with smokeless tobacco extract and nicotine, was assessed by measurement of changes in glutathione (GSH) and malondialdehyde (MDA) levels. CHO cells (5 x 10(5) cells/5 ml media) were incubated with 4, 0.8, and 0.08 mg of nicotine and STE containing the same amounts of nicotine. All preparations of smokeless tobacco extract significantly decreased GSH levels and increased MDA generation. However, 0.08 mg of nicotine treatment did not result in a significant change in GSH level, and only 4 mg of nicotine were sufficient to increase MDA generation. Addition of free radical scavenging enzymes, superoxide dismutase (SOD) and catalase (CAT), and an intracellular GSH precursor, N-acetyl-L-cysteine (NAC), replenished the GSH levels in nicotine-treated cells. GSH levels in cells exposed to smokeless tobacco extract containing 4 and 0.8 mg nicotine remained significantly lower than the control with the addition of SOD and CAT. However, co-addition of NAC with smokeless tobacco extract preparations returned the GSH levels to the control level. Lactate dehydrogenase (LDH) activities were measured in the media to establish the membrane damage following exposure to smokeless tobacco extract and nicotine. Treatment of cells with 4 mg nicotine caused a significant increase in LDH activity, which was returned to control level in the presence of the antioxidant enzymes and NAC. Smokeless tobacco extract did not change the LDH activity. http://link.springer-ny. com/link/service/journals/00244/bibs/37n4p434.html</++ +HEA
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Abstract
5-Aminolevulinic acid (ALA) is a heme precursor that accumulates in acute intermittent porphyria and lead poisoning. It has been shown that ALA induces free radical generation and may cause damage to proteins and DNA. In the present study, the effects of ALA on DNA damage and its prevention by N-acetyl-L-cysteine (NAC) and the antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD) are investigated. Oxidative damage to DNA was quantitated by measuring the increase in 8-hydroxy-2'-deoxyguanosine (oh8dG) formation. The time-course study demonstrated that ALA causes a linear increase in oh8dG levels in Chinese hamster ovary (CHO) cells. However, direct lead exposure did not cause any measurable increase in oh8dG levels. In the presence of either NAC (1 mM) or antioxidant enzymes (10 u/ml SOD and 10 u/ml CAT), oh8dG levels returned to the corresponding control levels. This suggests a protective role for NAC and the antioxidant enzymes. To determine the effect of ALA on cell proliferation, cell numbers were counted at the end of 24 h of incubation in the presence and absence of ALA at different concentrations. Results showed that levels of ALA up to 5 mM do not inhibit cell proliferation.
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Abstract
Nicotine affects a variety of cellular processes ranging from induction of gene expression to secretion of hormones and modulation of enzymatic activities. The objective of this study was to characterize the toxicity of nicotine enantiomers as well as their ability to induce oxidative stress in an in vitro model using Chinese hamster ovary (CHO) cells. Colony formation assay has demonstrated that (-)-nicotine is the more toxic of the enantiomers. At 6 mM concentrations, (-)-nicotine was found to be approximately 28- and 19-fold more potent than (+)-, and (+/-)-nicotine (racemic), respectively. Results also indicated that the toxicity of (+/-)-nicotine is higher than that of (+)-nicotine. (-)-Nicotine at a 10 mM concentration substantially decreased glutathione (GSH) levels (46% decrease). In addition, a 3-fold increase in malondialdehyde (MDA) level was evident in cells after exposure to 10 mM (-)-nicotine. Increased lactate dehydrogenase (LDH) activities in the media demonstrated that cellular membrane integrity was disturbed in nicotine treated cells. In the presence of superoxide dismutase (SOD) and catalase (CAT), the LDH activities returned to control value in 24 h with all concentrations of (-)-, (+)-, and (+/-)-nicotine. The decreases in LDH activities in the presence of the radical scavenging enzymes SOD and CAT suggest that membrane damage may be due to free radical generation.
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Abstract
delta-Aminolevulinic Acid (delta-ALA) is a heme precursor accumulated in lead poisoning and acute intermittent porphyria. Although no single mechanism for lead toxicity has yet been defined, recent studies suggest at least some of the lead-induced damage may originate from delta-ALA-induced oxidative stress. The present study was designed to test the hypothesis that delta-ALA accumulation in Chinese hamster ovary (CHO) cells contributes to the cumulative oxidative challenge of lead poisoning as indicated by the oxidative stress parameters glutathione (GSH), glutathione disulfide (GSSG), malondialdehyde equivalents (MDA), and catalase (CAT). It will also examine the possibility that this oxidative challenge can be reversed by treatment with an antioxidant such as N-acetylcysteine (NAC). First in vitro administration of delta-ALA to CHO cells was found to have a concentration-dependent inhibitory effect on colony formation and cell survival. NAC administration was shown to alleviate this inhibition in CHO survival. The oxidative status of CHO cell cultures exposed to increasing concentrations of delta-ALA was then examined. Decreases in GSH levels (P < 0.05) were observed in the delta-ALA-treated cultures as compared to the controls, while GSSG and MDA levels were significantly increased in delta-ALA-treated cells (P < 0.05). CAT activity was not significantly affected. NAC administration concurrent with delta-ALA exposure resulted in GSH and GSSG levels similar to the control levels, while no significant improvement in MDA was observed. These results indicate a state of oxidative stress and suggest that the delta-ALA- induced inhibitory effect on CHO colony formation may be due to its pro-oxidant effect. To assess whether this oxidative challenge would induce antioxidant increases during extended exposure to delta-ALA, CHO cells were exposed to 5 mM delta-ALA for increasing time periods. The GSH and GSSG levels were measured and a rebound effect was observed after 12 h of delta-ALA exposure.
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Abstract
Apoptosis has been described as programmed active cell death. Overexpression of the c-Myc gene has been shown to induce apoptosis in Rat1A/Myc-ER cells when combined with a growth blocking agent. In the present study, we tested whether 4-Hydroxynonenal (HNE) or N-acetyl-L-cysteine (LNAC) affect apoptotic death in serum deprived Rat1A/Myc-ER cells caused by the c-Myc protein. The incidence of apoptosis in growth arrested cells was confirmed photographically and by ladder pattern formation seen on agarose gel electrophoresis. To study the effect of HNE and LNAC, the cells were cultured in 0.5% serum and treated with various concentrations of HNE and LNAC, c-Myc was then activated by addition of 2 microM beta-estradiol. Two separate parameters were used to determine the rate of cell death. In the first, the amount of DNA isolated from dying cells was compared by UV absorption. As the second parameter, the cell numbers were determined by counting. Our results showed that 1 microM of HNE has no effect on apoptotic cell death. However, 10 microM HNE decreased the amount of DNA isolated while increasing the cell count 14% relative to cells treated only with beta-estradiol. In addition, we found that various concentrations of the antioxidant LNAC does not protect cells from c-Myc induced death. However, it supports cell survival in 0.5% serum and causes an increase in cell number.
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