Dynamic examination of closed cylindrical shells utilizing the differential transform method.

This article presents an innovative approach using the Differential Transform Method (DTM) to analyze the vibration characteristics of cylindrical shells, integrating Taylor's series with Sander's classical theory. It demonstrates DTM's efficiency, accuracy, and potential as an alternative method. The study introduces a novel application of the DTM in exploring the free vibration of cylindrical shells, detailing a technique to address challenges such as normalization, linear solution methodologies, and parameter derivative modifications. A dimensionless parameter analysis evaluates the impact of length, radius, thickness, and modulus of elasticity. Comparative analysis with Hybrid Finite Element Method (FEM) data and validation against existing literature highlights DTM's precision and reliability. In conclusion, DTM offers a robust solution for the eigenvalue problem in coupled differential equations, providing accurate vibration parameters. Additionally, an important relationship between the modulus of elasticity and frequency in the dimensionless state was obtained.

Antiplatelet Resistance in Coronary Artery Bypass Grafting: A Systematic Review.

Background: This systematic review examines the occurrence and implications of resistance to primary antiplatelet agents, aspirin and clopidogrel, often utilised in patients undergoing coronary artery bypass grafting (CABG), alongside the methodologies for assessment of such resistance. Methods: An extensive literature search across various databases such as PubMed, MEDLINE via Ovid, Embase, and Cochrane CENTRAL until May 2024 was conducted to identify studies evaluating antiplatelet resistance in on-pump and off-pump CABG patients. Following quality assessment, only high-quality studies were incorporated into this review. Results: This review included 19 studies with 3,915 patients, four of which were randomised controlled trials and 15 were observational studies. Aspirin resistance incidence ranged from 11.0% to 51.5%, while clopidogrel resistance was 22%. Antiplatelet resistance, assessed through a wide variety of methods, was associated with a 13 times increase in the risk of vein graft occlusion and increased rates of mortality, myocardial infarction, and target vessel revascularisation in the case of clopidogrel resistance. The effect of cardiopulmonary bypass on antiplatelet resistance remains ambiguous. Conclusion: The academic literature lacks a standardised definition for antiplatelet resistance. Assessment methodologies greatly vary, leading to noninterchangeable outcomes. While aspirin resistance has a conflicting overall significant impact on adverse outcomes, clopidogrel resistance correlates with poorer clinical outcomes.

Enhanced adsorption and removal of Cd(II) from aqueous solution by amino-functionalized ZIF-8.

Zeolite imidazolate framework-8 (ZIF-8), which is a special subgroup of metal-organic frameworks (MOFs), was synthesized and modified by ethylenediamine (ZIF-8-EDA) to prepare an efficient adsorbent for the high sorption of Cd2+ ions from solution. The synthesized and modified ZIF-8 (ZIF-8-EDA) were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, Brunauer-Emmett-Teller (BET), field emission scanning electron microscopy (FE-SEM) with energy dispersive spectroscopy (EDS), and transmission electron microscopy (TEM) analysis. The optimum conditions for dosage of adsorbent, initial ion concentration, pH, and contact time were 0.05 g/l, 50 mg/l, 6, and 60 min, respectively, for cadmium ion sorption from aqueous solutions with a removal efficiency of 89.7% for ZIF-8 and 93.5% for ZIF-8-EDA. Adsorption kinetics and equilibrium data were analyzed using the Langmuir and Freundlich equations. The Langmuir model fitted the equilibrium data better than the Freundlich model. According to the Langmuir equation, the maximum uptake for the cadmium ions was 294.11(mg/g). The calculated thermodynamic parameters (ΔG°, ΔH°, and ΔS°) indicated that the adsorption process was feasible, spontaneous, and endothermic at 20-50 °C. Based on the results, the amino functionalized ZIF-8 had improved adsorption performance due to the replacing of the starting linker with organic ligands that had effective functional groups, leading to chemical coordination due to the interaction of metal ions with the non-bonding pair of electrons on the N atoms of the amino functional group. The selectivity toward metal ion adsorption by ZIF-8-EDA was Cd2+ > Pb2+ > Ni2+ .

Clinical Phenotype and Disease Course of Inflammatory Bowel Disease in Iran: Results of the Iranian Registry of Crohn's and Colitis (IRCC).

BACKGROUND: Data on the epidemiology of inflammatory bowel disease (IBD) in the Middle East are scarce. We aimed to describe the clinical phenotype, disease course, and medication usage of IBD cases from Iran in the Middle East. METHODS: We conducted a cross-sectional study of registered IBD patients in the Iranian Registry of Crohn's and Colitis (IRCC) from 2017 until 2022. We collected information on demographic characteristics, past medical history, family history, disease extent and location, extra-intestinal manifestations, IBD medications, and activity using the IBD-control-8 questionnaire and the Manitoba IBD index, admissions history, history of colon cancer, and IBD-related surgeries. RESULTS: In total, 9746 patients with ulcerative colitis (UC) (n=7793), and Crohn's disease (CD) (n=1953) were reported. The UC to CD ratio was 3.99. The median age at diagnosis was 29.2 (IQR: 22.6,37.6) and 27.6 (IQR: 20.6,37.6) for patients with UC and CD, respectively. The male-to-female ratio was 1.28 in CD patients. A positive family history was observed in 17.9% of UC patients. The majority of UC patients had pancolitis (47%). Ileocolonic involvement was the most common type of involvement in CD patients (43.7%), and the prevalence of stricturing behavior was 4.6%. A prevalence of 0.3% was observed for colorectal cancer among patients with UC. Moreover,15.2% of UC patients and 38.4% of CD patients had been treated with anti-tumor necrosis factor (anti-TNF). CONCLUSION: In this national registry-based study, there are significant differences in some clinical phenotypes such as the prevalence of extra-intestinal manifestations and treatment strategies such as biological use in different geographical locations.

Extracellular vesicles as a new horizon in the diagnosis and treatment of inflammatory eye diseases: A narrative review of the literature.

Extracellular vesicles include exosomes, microvesicles, and apoptotic bodies. Their cargos contain a diverse variety of lipids, proteins, and nucleic acids that are involved in both normal physiology and pathology of the ocular system. Thus, studying extracellular vesicles may lead to a more comprehensive understanding of the pathogenesis, diagnosis, and even potential treatments for various diseases. The roles of extracellular vesicles in inflammatory eye disorders have been widely investigated in recent years. The term "inflammatory eye diseases" refers to a variety of eye conditions such as inflammation-related diseases, degenerative conditions with remarkable inflammatory components, neuropathy, and tumors. This study presents an overview of extracellular vesicles' and exosomes' pathogenic, diagnostic, and therapeutic values in inflammatory eye diseases, as well as existing and potential challenges.

Serum androgens and prolactin levels in patients with keratoconus.

CLINICAL RELEVANCE: There is growing evidence for the involvement of sex hormones in the pathogenesis of keratoconus. BACKGROUND: This study aimed to evaluate serum androgen and prolactin levels in patients suffering from keratoconus. METHODS: One hundred and two subjects were enrolled in the keratoconus (76 patients) and control (26 subjects) groups in a cross-sectional survey. Topographic evaluation of the cornea was undertaken for all enrolled participants. Serum testosterone, dehydroepiandrosterone sulphate (DHEAS), prolactin (PRL), luteinising hormone (LH), and follicle-stimulating hormone (FSH) were measured in all subjects. RESULTS: There was no significant difference in demographic characteristics between the study groups. Significantly higher mean serum levels of DHEAS (3.71 ± 2.23 vs. 2.53 ± 1.77 µg/mL; P = 0.009) and T (6.18 ± 3.80 vs. 1.57 ± 1.76 ng/mL; P < 0.001) were observed in men with keratoconus compared to controls. In females, there were also higher mean levels of DHEAS (2.40 ± 1.57 vs. 2.18 ± 0.72 µg/mL; P = 0.355) and T (0.78 ± 0.96 vs. 0.32 ± 0.13 ng/mL; P < 0.001) in patients with keratoconus but only T level reached the statistically significant level of difference. Also, the mean serum PRL level was significantly higher in women with keratoconus compared to control (13.33 ± 17.85 vs. 4.63 ± 3.10 ng/mL; P < 0.001). There was no significant difference between serum FSH and LH levels between study groups. CONCLUSION: In patients with keratoconus, serum PRL in females and serum androgen levels in both genders are elevated.

Inferior Spear-like Lens Opacity as a Sign of Keratoconus.

PURPOSE: To report 21 cases of typical inferior feather-shape lens opacity associated with keratoconus. METHODS: In this cross-sectional study, we evaluated the association of keratoconus with inferior feather-shape lens opacity in refractive surgery candidates. Visual acuity, demographic, refractive, and topographic characteristics of 26 eyes of 21 patients with inferior feather-shape lens opacity were evaluated in detail. Pedigree analysis was also performed to assess possible inheritance. RESULTS: Overall, 2122 out of 33,368 cases (6.4%) without lens opacity had keratoconus, while 20 out of 21 patients (95.2%) with peculiar lens opacity had definite keratoconus (P < 0.001). Lens opacity was bilateral in 5 cases (24%), and keratoconus was bilateral in all 20 patients with lens opacity. Nine eyes out of thirty-six with a complete data record (25%) had a severe keratoconus and underwent deep lamellar keratoplasty, while 11 (31%) had forme fruste keratoconus. Pedigrees were drawn for eight patients, most families of whom suggested an X-linked recessive inheritance. CONCLUSION: The present study was the first to investigate patients with a peculiar inferior feather-shape lens opacity accompanied by bilateral keratoconus, which was observed in 95% of the patients. This finding should raise awareness as to the possibility of diagnosing keratoconus in the eyes of the patients with these characteristics.

Novel RNA extraction method from human tears.

Human tears can be used as a noninvasive source of genetic materials and biomarkers in the prognosis and diagnosis of ocular and non-ocular diseases. The present protocol is a novel direct RNA extraction method from tears. This study aims to provide a suitable method for direct extraction of RNA from tears with high quality and quantity. In this study, we develop a TRIzol base protocol for direct RNA extraction from human tears. quality and quantity of extracted RNA measured by calculation of 260/280 UV absorption ratio using Nanodrop and real-time PCR. RNA was extracted with this modified method and a purified (260/280 UV absorption ratio between 1.8 to 2 and a high yield of total RNA, on average 95 µg, from tears was extracted. In conclusion, we developed an easy and suitable method for direct extraction of total RNA from tears with high quality and quantity.

Extra-thoracal migration of the Nuss Bar in corrective surgery for pectus excavatum: a very rare late complication.

Pectus excavatum is a chest wall deformity with an incidence of around 1 in 400 live births. The Nuss procedure is a surgical intervention that aims to restore functional integrity in these patients. We report the first case of bar migration into the stomach necessitating further surgical intervention for removal. Our case presents a rare complication of pectus excavatum repair and highlights the importance of vigilant follow-up in these patients. If bar migration does occur, imaging in the form of X-ray and CT scans may be of use in early detection in order to expedite management.

Corneal Cross-linking as an Adjunct for The Management of Refractory Fungal Keratitis.

PURPOSE: To evaluate the effectiveness of ultraviolet (UV)-A/Riboflavin corneal cross-linking (CXL) for the treatment of the refractory cases of fungal keratitis. METHODS: In this prospective interventional study, 9 patients with the diagnosis of fungal keratitis that were referred to our emergency eye center were included. These patients were resistant to conventional treatment and underwent therapeutic UV-A/Riboflavin CXL. Response to the treatment was considered as good if rapid epithelialization and rapid decrease in stromal infiltration was occurred after PACK-CXL, and poor when the emergency transplantation was necessary to eradicate the infection. RESULTS: Nine patients treated with CXL due to recalcitrant fungal keratitis. Culture of the corneal scrapings showed Aspergillus species in 4 patients, Candida albicans in 1 patient and Fusarium species in the remainder of them. CXL was performed from 1 to 20 days after the presentation of corneal ulcers (Mean: 9.12 ± 4.02; range: 5-20 days). Postoperatively, the mean time to epithelialization was 14.25 ± 2.38 days, and mean time to resolution of stromal infiltration was 22.5 ± 7.29 days, in responsive cases. Four out of 9 eyes showed good response, and five patients showed no response, and corneal transplantation was performed to eradicate the infection. There was no statistically significant difference in mean depth of infiltration and mean size of ulcer between responsive and unresponsive patients (P = 0.86 and 0.08, respectively). CONCLUSION: Although UV-A/Riboflavin CXL is not a definite treatment for all of the fungal keratitis, it seems promising in the management of some refractory cases.

Therapeutic Effect of Intrastromal Voriconazole, Topical Voriconazole, and Topical Natamycin on Fusarium Keratitis in Rabbit.

Purpose. Evaluating the therapeutic effect of topical and intrastromal voriconazole and topical natamycin on Fusarium keratitis. Methods. 24 rabbits were selected. The stroma of their corneas was inoculated with suspension of Fusarium solani species complex. Seven days after injection they were divided into 4 groups randomly: the first group was treated with topical voriconazole (TV) 1% for one week, the second one with one-time intrastromal injection of voriconazole (ISV) 50 microgram/0.1 mL, and the third group with topical gel of natamycin (TN) for one week, and the last one did not receive any antifungal treatment. Finally the eyes were enucleated and sclerocorneal buttons were sent for histological and microbiological examinations. Results. After treatment the ISV group and TN group showed significantly lower clinical score and colony forming units than the control group (P = 0.040 and P = 0.026, resp.), but there was statistically no significant difference between control and TV groups (P = 0.249) or between ISV and TN groups (P = 0.665). In pathological evaluation, fewer chronic inflammations were reported in 2 of the 3 buttons from TV group and 3 of the 3 buttons from ISV and TN groups in comparison with the control group. Conclusion. Intrastromal injection of voriconazole seems to be effective in treatment of Fusarium keratitis as much as topical natamycin and these are more effective than topical voriconazole.

Brain-derived neurotrophic factor in patients with advanced age-related macular degeneration.

AIM: To investigate the serum level of the brain-derived neurotrophic factor (BDNF) in age-related macular degeneration (AMD) and healthy control subjects. The disruption in the tight balance of neuroinflammatory and neuroprotective processes in an immune-privileged site like retina is proposed to contribute to the pathogenesis of AMD. One of the main neuroprotective mediators in the central nervous system is BDNF with its serum level notably affected in several neurodegenerative disorders. METHODS: Thirty-six patients with AMD and 36 age-matched controls were enrolled in this study. The serum level of BDNF was measured using the enzyme-linked immunosorbent assay method. Results were analyzed to compare case and control values. Comparisons were also made between the BDNF level of wet- vs dry-AMD, and male vs female patients and controls. Analysis of variance (ANOVA) and Student's t-test were employed to analyze the data. RESULTS: The mean BDNF levels in AMD group were significantly higher than the control group. Furthermore, our analysis revealed greater BDNF values in all AMD subgroups compared to controls (P=0.004, 0.005, 0.001 and 0.02 for male wet-AMD, male dry-AMD, female wet-AMD and female dry-AMD vs controls, respectively). The BDNF level however did not vary between wet- and dry-AMD patients (P=0.74). While within-group comparisons in males and females of AMD and control groups did not show any difference in BDNF (P=0.16, 0.64 and 0.85 for wet-AMD, dry-AMD and control groups, respectively), between-group data showed a higher mean BDNF in both male and female AMD subjects than their peer controls. CONCLUSION: This study demonstrated that the serum BDNF level is different in patients with AMD as compared to subjects without AMD. Future attempts should be done to unravel beneficial or deleterious effect of this neurotrophin in the pathogenesis of AMD.

Bacterial keratitis in a tertiary eye centre in Iran: a retrospective study.

PURPOSE: To report the characteristics and laboratory findings of 182 patients with bacterial keratitis diagnosed at Farabi Eye Hospital in Tehran, Iran. MATERIALS AND METHODS: In this retrospective study, data were collected on demographics, risk factors, location, size and depth of the ulcer, height of the hypopyon, uncorrected visual acuity, results of smear and culture tests, and antibiotic sensitivity of cultured bacteria. RESULTS: There were 110 (60.4%) males and 72 (39.6%) females with an average age of 56.0 ± 2.3 years. Ocular trauma (17.6%) and positive history of corneal surgery (14.3%) were major risk factors. The mean age of contact lens users was 22.5 ± 7.7 years. Sixty patients (33%) used topical antibiotics, 21 (11.5%) patients utilized topical steroid, and 26 (14.3%) cases used both topical antibiotic and steroid at presentation. Culture results were, 81 (44.5%) cases were Gram-positive, 63 (34.6%) were Gram-negative, 10 (5.5%) were mixed bacteria and in 28 (15.4%) cases had detected growth. The isolated bacterial species from the corneal ulcers were less resistant to ceftazidime (6%) and amikacin (6%). The majority of patients were treated with medical therapy; however, 81 cases (44.5%) received at least one surgical procedure. CONCLUSION: Among the patients with bacterial corneal ulcers, trauma was the most common risk factor. Over-the-counter antibiotic and steroid were commonly used in the majority of patients. The most common bacteria isolated were Gram-positives, and they were less resistant to ceftazidime and amikacin. Penetrating keratoplasty was the most common surgical procedure in patient who required surgery.

Ultraviolet A/riboflavin collagen cross-linking for treatment of moderate bacterial corneal ulcers.

PURPOSE: To evaluate the therapeutic effect of UV-A/riboflavin collagen cross-linking (CXL) on moderate bacterial corneal ulcers. METHODS: Thirty-two patients with moderate bacterial keratitis were selected. All patients were treated according to the standard medical treatment protocol. The patients were randomly allocated to 2 groups: case and control groups of 16 patients each using a numerical randomization table. The case group received CXL treatment. In the CLX group, corneal epithelium was removed and 0.1% riboflavin drops were applied. Then the corneas were irradiated with UV-A (365 nm) with an irradiance of 3 mW/cm for 30 minutes. The grade of ulcers, size of epithelial defects, and area of infiltrates were recorded on days 1, 7, and 14 of treatment. RESULTS: There was no statistically significant difference between the groups 1 day after the treatment. The mean treatment duration was 17.2 ± 4.1 days in the CXL group and 24.7 ± 5.5 days in the control group. The epithelial defects were smaller in the CXL group at 7 days (P = 0.001) and 14 days (P = 0.001) after the beginning of treatment. The area of infiltrates in CXL group was smaller than the control group at both 7 days (P = 0.001) and 14 days (P < 0.001) after the start of treatment. CONCLUSIONS: Our results support the beneficial effect of CXL in patients with moderate bacterial keratitis. In addition to accelerating epithelialization, this method shortens the course of treatment and may minimize or remove the need for surgery or other serious sequelae, such as corneal perforation.

Early cholestasis in neonatal lupus erythematosus.

Neonatal lupus erythematosus is an immune-mediated disease caused by transplacental passage of maternal autoantibodies, primarily anti-Ro (SSA) and anti-La (SSB). The major clinical manifestations are congenital heart block, cutaneous lupus lesions, and hematologic problems. Hepatic, pulmonary, and neurological involvements are rare. We report a 5-day-old male neonate, born to a clinically asymptomatic mother, presenting with conjugated hyperbilirubinemia, cutaneous lupus lesions, congenital heart block, and thrombocytopenia. Both the neonate and his mother had high titers of antinuclear antibodies (1:640), anti-Ro (SSA), and anti-La (SSB) antibodies. The thrombocytopenia improved with prednisolone (2 mg/kg/day) for 14 days. The skin lupus rashes and bilirubin resolved 2 months later, and liver enzymes were completely normal by 6 months.

Pericardial suction blood separation attenuates inflammatory response and hemolysis after cardiopulmonary bypass.

OBJECTIVES: Retransfusion of pericardial suction blood (PSB) is critically considered under the aspect of the biocompatibility of the cardiopulmonary bypass (CPB). We investigated various indicators of inflammation and blood cell activation associated with CPB and re-transfusion of PSB during cardiac surgery. DESIGN: Thirty-five patients undergoing elective coronary artery bypass grafting were prospectively randomized into two groups. In group A (n = 15, retransfusion group) the pericardial suction blood was continuously retransfused during CPB, in group B (n = 20, no-retransfusion group) the suction blood was separated. Parameters indicating the status of the inflammation and blood cell activation were analyzed before and at the end of CPB, latest after 90 minutes on CPB. RESULTS: Patients' perioperative data did not differ between groups. The inflammatory markers C-reactive protein, PMN-Elastase and Interleukin-6 increased in both groups after CPB (p < 0.04) with significantly lower values in the no-retransfusion group (p < 0.02). Leukocytes and platelet activation markers beta-Thromboglobulin and soluble P-Selectin also experienced a significant elevation during observation time (p < 0.02) without any difference between the groups. Free hemoglobin and LDH tremendously increased during CPB with lower values in the no-retransfusion group. CONCLUSIONS: Cardiotomy suction is a major cause of hemolysis and contributes significantly to the systemic inflammatory response.

Effects of poly-2-methoxyethylacrylate (PMEA)-coating on CPB circuits.

OBJECTIVES: In this study, the immuno- and neuroprotective effect of a novel cardiopulmonary bypass coating was investigated. DESIGN: Thirty nine patients scheduled for elective coronary artery bypass grafting were randomly assigned to either PMEA-coated (n = 19) or non-coated CPB circuits (n = 20). Pericardial suction blood was separated and retransfused only if needed at the end of operation. Neurocognitive functions were examined preoperatively and 7-10 days postoperatively using a standard neuropsychological test battery. Assuming an inflammatory etiology, the most cogent inflammatory markers were perioperatively analyzed. RESULTS: Postoperatively, patients of the PMEA-coated group performed better in Go/NoGo and Mini-Mental-test than patients of the non-coated group (p < 0.04). Other neurocognitive testing did not reveal significant differences between the groups. Although most inflammatory parameters showed a significant intraindividual increase during or shortly after CPB, there was no difference in inflammatory alteration between the groups. CONCLUSIONS: PMEA-coating of cardiopulmonary bypass surfaces revealed some minor benefits in preservation of neurocognitive functions after surgery. The immediate inflammatory response remained mostly unaffected. Suction blood separation may additionally contribute to proper postoperative outcome.