ABSTRACT
In this study, we investigate the role of adding shear thickening fluids (STFs) and multi-functional shear thickening fluids (M-STFs) to the core of a sandwich-structured composite made of aluminum facesheets and XPS foam cores with different geometries on force attenuation performance. Six different core designs were machined, and all designs had the same space for adding STFs and M-STFs. STF with 40 wt% SiO2 in PEG 400 was selected and fabricated. M-STFs were made by adding multi-walled carbon nanotubes (MWCNTs) up to 1.5 wt%. The effects of MWCNTs on the rheological and electrical properties of the STF were investigated. The force attenuation tests were performed with an impact drop tower test system at three different heights with 5, 10, and 15 J energy levels. According to the results, V6_STF (with 16 holes with a diameter of 6 mm) and H6_STF (with 16 rectangular cubic column with cross-sections of 6 × 6 mm) designed sandwich structures showed better performance in terms of force attenuation compared with the other samples. Next, these two sandwich structures were filled again with M-STF (0.5 wt% MWCNT), and the force attenuation performance of the structures showed an improvement further, and the H6_STF_CNT sample improved by 24.8% compared to the clean sandwich structure sample. These results demonstrate the potential of STFs and M-STFs in strengthening the force attenuation performance of sandwich structures with XPS foam cores, mainly when used with appropriate core geometry.
ABSTRACT
OBJECTIVE: A 1-day point prevalence study was planned to obtain country data by determining the clinical characteristics, follow-up and treatment methods of coronavirus disease 2019 (COVID-19) cases that required intensive care unit (ICU) treatment in the second year of the pandemic. MATERIAL AND METHODS: All patients who were hospitalized in the ICUs due to COVID-19 between March 11, 2022, 08.00 am, and March 12, 2022, 08.00 am, were included in the study. Demographic characteristics, intensive care and laboratory data, radiological characteristics, and follow-up results of the patients were recorded. RESULTS: A total of 811 patients from 59 centers were included in the study, 59% of the cases were male, and the mean age was 74 ± 14 years. At least one comorbid disease was present in 94% of the cases, and hypertension was the most common. When ICU weight scores were examined, Acute Physiology and Chronic Health Evaluation-II: 19 (15-27) and Sequential Organ Failure Assessment: 7 (4-10) were seen. Sepsis was present in 37% (n = 298) of cases. PaO2/FiO2 ratios of the patients were 190 the highest and 150 the lowest and 51% of the cases were followed via invasive mechanical ventilation. On the study day, 73% bilateral involvement was seen on chest x-ray, and ground-glass opacities (52%) were the most common on chest tomography. There was growth in culture in 40% (n = 318) of the cases, and the most common growth was in the tracheal aspirate (42%). CONCLUSION: The clinical course of COVID-19 is variable, and ICU follow-up was required due to advanced age, comorbidity, presence of respiratory symptoms, and widespread radiological involvement. The need for respiratory support and the presence of secondary infection are important issues to be considered in the follow-up. Despite the end of the second year of the pandemic and vaccination, the high severity of the disease as well as the need for follow-up in ICUs has shown that COVID-19 is an important health problem.
ABSTRACT
Acquired tamoxifen resistance is a persistent problem for the treatment of estrogen receptor positive, premenopausal breast cancer patients and predictive biomarkers are still elusive. We here analyzed gene expression changes in a cellular model to identify early and late changes upon tamoxifen exposure and thereby novel prognostic biomarkers. Estrogen receptor positive MCF-7 cells were incubated with 4OH-tamoxifen (10 nM) and gene expression analyzed by array hybridization during 12 weeks. Array results were confirmed by nCounter- and qRT-PCR technique. Pathway enrichment analysis revealed that early responses concerned mainly amine synthesis and NRF2-related signaling and evolved into a stable gene expression pattern within 4 weeks characterized by changes in glucuronidation-, estrogen metabolism-, nuclear receptor- and interferon signaling pathways. As a large number of long non coding RNAs was subject to regulation, we investigated 5 of these (linc01213, linc00632 linc0992, LOC101929547 and XR_133213) in more detail. From these, only linc01213 was upregulated but all were less abundant in estrogen-receptor negative cell lines (MDA-MB 231, SKBR-3 and UACC3199). In a web-based survival analysis linc01213 and linc00632 turned out to have prognostic impact. Linc01213 was investigated further by plasmid-mediated over-expression as well as siRNA down-regulation in MCF-7 cells. Nevertheless, this had no effect on proliferation or expression of tamoxifen regulated genes, but migration was increased. In conclusion, the cellular model identified a set of lincRNAs with prognostic relevance for breast cancer. One of these, linc01213 although regulated by 4OH-tamoxifen, is not a central regulator of tamoxifen adaption, but interferes with the regulation of migration.
Subject(s)
Breast Neoplasms/genetics , Drug Resistance, Neoplasm , Gene Expression Profiling/methods , RNA, Long Noncoding/genetics , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Cell Movement , Cell Proliferation , Female , Gene Expression Regulation, Neoplastic , Gene Regulatory Networks , Humans , MCF-7 Cells , Prognosis , Receptors, Estrogen/metabolism , Tamoxifen , Time FactorsABSTRACT
OBJECTIVE: To determine the changes in liver function tests after long-term risperidone treatment in a child and adolescent population. METHODS: Weight, alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transpeptidase, alkaline phosphatase and serum bilirubin of the patients were assessed in pre-treatment period, and at the sixth and 12th months of treatment. One hundred children and adolescents (aged between 3 and 18 years) were enrolled to the study. RESULTS: Liver enzyme and bilirubin levels are higher than normal in 21.0% of the patients without clinical symptoms. No cases of hepatic failure or jaundice were seen. Only in an 8-year-old boy were there ALT level increases up to three-fold and AST level increases up to two-fold. After discontinuation of the risperidone treatment, enzyme levels were normalized in this patient. Alkaline phosphatase, alanine and aspartate aminotransferases were the most frequently increased enzymes. CONCLUSION: In this study, after long-term risperidone treatment of children and adolescents there was no evidence of clinically significant increases of liver enzymes and bilirubin levels. These results indicate that risperidone treatment may rarely cause serious liver enzyme increases, and may commonly cause clinically insignificant changes in liver function tests.
Subject(s)
Liver Function Tests/methods , Risperidone/therapeutic use , Adolescent , Bilirubin/biosynthesis , Bilirubin/blood , Child , Child, Preschool , Female , Humans , Liver Diseases/blood , Liver Diseases/enzymology , Liver Diseases/epidemiology , Liver Function Tests/trends , Longitudinal Studies , Male , Observation , Risperidone/adverse effects , Time Factors , TurkeyABSTRACT
OBJECTIVE: Risperidone is a promising agent for the treatment of schizophrenia, Tourette's disorder, mood disorders, and disruptive behavior disorders in young populations. However, adverse effects of risperidone may take a long time to emerge. The objective of this study was to investigate the changes in the liver function tests (LFTs) associated with more than 6 months of risperidone treatment in children and adolescents. METHOD: A total of 102 youths treated with risperidone for more than 6 months were eligible for the study. For this study, patients' baseline and follow-up weight and hepatobiliary function tests, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), and serum bilirubin levels, were measured at baseline and at 6 months. RESULTS: Asymptomatic abnormalities of LFTs, mostly ALP elevation, were found in 38.2% of the cases, and marked elevation of liver enzymes was found in 0.8% of cases treated with risperidone. The mean levels of liver enzymes and bilirubin of the patients were significantly higher than the baseline after first and sixth months of treatment. However, there was no statistically significant change in the liver enzymes and bilirubin levels between the first and sixth months. There was no significant relationship between changes in weight and liver enzymes and bilirubin levels after 6 months of risperidone treatment. CONCLUSION: These findings suggest that risperidone treatment in the long term commonly leads to liver function changes, although at therapeutic doses in children and adolescents it may rarely induce a serious hepatic toxicity. Concomitant use of antidepressants and methylphenidate and variations in age and pubertal status are limitations of present study. Further studies are needed to assess the importance and role of other variables over LFT abnormalities in youth population.
Subject(s)
Antipsychotic Agents/adverse effects , Antipsychotic Agents/therapeutic use , Attention Deficit and Disruptive Behavior Disorders/drug therapy , Liver/drug effects , Risperidone/adverse effects , Risperidone/therapeutic use , Schizophrenia/drug therapy , Adolescent , Body Weight/drug effects , Child , Child, Preschool , Female , Humans , Liver/physiology , Liver Function Tests , Longitudinal Studies , Male , Time Factors , TurkeyABSTRACT
The prescribed use of methylphenidate in the treatment of attention deficit hyperactivity disorder (ADHD) is widespread. The intranasal and parenteral abuse of methylphenidate (Ritalin) among teenagers is becoming increasingly more common, and deaths have been reported. Newer medical treatment options of long-acting stimulants offer effective treatment with a lower risk of abuse potential. We describe a case of a 17-year-old girl who had attempted suicide by ingesting 270 mg of Concerta. During the third years of treatment with Concerta, parents of patient reported that the patient had a depressive mood in the last week, and had attempted suicide with five tablets of Concerta 54 mg. She was sent to a local hospital with a diagnosis of long-acting methylphenidate overdose. All of vital and laboratory findings were normal except heart rate, which was 132 beats/min. Since more than 3 h have elapsed after the time of ingestion, activated charcoal administration was not carried out at the hospital. She was only observed for 12 h at the emergency department and later discharged from the hospital. While long-acting stimulants offer lower risk of abuse, their greater availability increases the likelihood of ingestion of this nature. Education of clinicians and families to be aware of this risk should reduce the frequency of this complication of treatment.
Subject(s)
Central Nervous System Stimulants/poisoning , Delayed-Action Preparations/poisoning , Methylphenidate/poisoning , Suicide, Attempted , Adolescent , Central Nervous System Stimulants/administration & dosage , Drug Overdose , Female , Humans , Methylphenidate/administration & dosageABSTRACT
BACKGROUND AND OBJECTIVES: In this study, we compare paravertebral block (PVB) of the T10 and L1 segments and multiple-segment PVB for anesthesia and analgesia in inguinal hernia surgeries. METHODS: Anatomic study was performed on 3 cadavers. A 15-mL methylene blue solution was injected at the T10 level and then an additional 5-mL dye injection at L1 level. Fifty patients were included in the study. Patients in group 1 (n = 25) underwent PVB of 2 segments at the T10 and L1 vertebrae levels on the same side as the hernia, whereas patients in group 2 (n = 25) underwent PVB through 4 segments at T10, T11, T12, and L1 on the same side as the hernia. Perioperative propofol/remifentanil consumption, surgery start time, time to perform the block, duration of sensory block, postoperative visual analog scale scores, and complications were evaluated. RESULTS: Any passage down to the T12 level was not observed after injection at the T10 level and also only after additional 5-mL dye injection at the L1 level; the genitofemoral, ilioinguinal, iliohypogastric, and lateral femoral cutaneous nerves were stained with dye in cadavers. The times for block application were 5 mins (SD, 1 min) in group 1 and 16 mins (SD, 4 mins) in group 2 (P < 0.001). The surgery start time was 25 mins (SD, 3 mins) in group 1 and 27 mins (SD, 6 mins) in group 2 (P = 0.234). In both groups, propofol and remifentanil were used in similar quantities during the perioperative period. Use of paracetamol tablets was similar in both groups (P > 0.05). Whereas none of the patients in group 1 displayed motor block or contralateral spread, 2 patients in group 2 displayed contralateral spread, and motor block was observed in 1 patient. Twenty-three patients (92%) in group 1 and 24 patients (96%) in group 2 were satisfied with the method (P > 0.05). CONCLUSION: Two-segment PVB can be an alternative to 4-segment PVB in inguinal hernia surgeries. Decreasing the number of injections required in this technique may further increase patient comfort and decrease complications.