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1.
Macromol Rapid Commun ; : e2300746, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488683

RESUMO

Polyolefins, composed of carbon and hydrogen atoms, dominate global polymer production. This stems from the wide range of physical and mechanical properties that various polyolefins can cover. Their versatile properties are largely tuned by chain microstructure, including molar mass distribution, comonomer content, and long-chain branching (LCB). Specifically, LCB imparts unique characteristics, notably enhances processability crucial for downstream applications. Tailoring LCB structural features has encouraged academic and industrial efforts, chronicle in this review from a chemistry standpoint. While encompassing post-reaction modification based traditional methods like peroxide grafting, ionizing beam irradiation, and coupling reactions, the main focus is given to catalyst-centric strategies and innovative polymerization schemes. The advent of single-site catalysts-metallocenes and late transition metals catalysts-amplifies interest in tailored chemical methods, but the progress in LCB formation flourishes via tandem catalytic systems and bimetallic catalysts under controlled reaction conditions. Specifically, the breakthrough in coordinative chain transfer polymerization unveils a novel avenue for controlled LCB synthesis by sequential chain propagation, transfer, liberation, and enchainment. This short review highlights recent approaches for the production of LCB polyolefins that can provide a roadmap crucial for researchers in academia and industry, steering their efforts toward further advancements in the production of tailored polyolefin.

2.
Vet Med Sci ; 10(1): e1344, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38227704

RESUMO

BACKGROUND: Enzyme combinations, particularly phytase (PHY) with various carbohydrases and proteases, are utilized in commercial broiler production to enhance nutrient and energy bioavailability. OBJECTIVE: A feeding study was undertaken to determine whether the efficiency of an Escherichia coli-derived PHY and a feed enzyme complex (FEC) derived from Bacillus spp. containing carbohydrase and protease as main activities in broiler chickens is dependent on diet quality. A total of 900 male one-day-old broiler chickens (Ross 308) were assigned to a 2 × 3 factorial arrangement of the treatments with 2 different nutrient density diets, standard nutrient diet (SN diet) and a low-nutrient diet (LN diet; -100 kcal/kg for AMEn and -5% for crude protein [CP] and limiting amino acids), and 3 enzyme treatments (control [no enzymes], PHY and PHY + FEC). Each treatment group was composed of 6 replicates of 25 birds each. RESULTS: The LN diet caused a decrease in performance index, tibia length and diameter, tibia calcium content and jejunal villus surface area (VSA). The interaction effects between diet and enzyme supplementation were observed (p < 0.05) on overall average daily gain (ADG), performance index, tibia ash content and jejunal villus height (VH) and VSA, with the favourable benefits of PHY + FEC treatment being more pronounced in the LN diets. Regardless of dietary nutrient density, supplementation with PHY alone or combined with FEC enhanced (p < 0.05) final body weight, overall ADG and jejunal villus height (VH)/crypt depth, with the highest values observed in the PHY + FEC group. The PHY + FEC treatment also improved (p < 0.05) overall feed conversion ratio, apparent ileal digestibility of dry matter, organic matter, CP, and energy, and tibia phosphorus content compared to the control treatment. CONCLUSIONS: The results indicate that the simultaneous addition of PHY and FEC to the LN diets improved the growth rate, bone mineralization and gut morphology.


Assuntos
6-Fitase , Suplementos Nutricionais , Glicosídeo Hidrolases , Animais , Masculino , Galinhas , 6-Fitase/metabolismo , 6-Fitase/farmacologia , Peptídeo Hidrolases/farmacologia , Calcificação Fisiológica , Escherichia coli , Digestão , Dieta/veterinária , Nutrientes , Ração Animal/análise
3.
Phys Chem Chem Phys ; 25(48): 32955-32965, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38019135

RESUMO

The combination of supramolecular chemistry and polymer science has resulted in the development of transient polymer networks with diverse properties and applications. Specifically, polymer networks based on transient linking of telechelic polymer precursors offer a high degree of control over the network structure, which can reform in response to external stimuli that change the connectivity of transient bonds. Therefore, the combination of the versatile polymer functionality and the adjustable connectivity of transient bonds may result in complex network structures that are not easy to predict or characterize. To address this gap, herein we extend the Miller-Macosko model to forecast the network connectivity of transient telechelic polymer networks made with various polymer functionalities and transient connectivities represented by metal-ligand complexes. This model predicts a universal dependence of the network structure and modulus on preparative parameters including the metal ion identity, characterized by the complexation thermodynamics, and concentration. Moreover, we demonstrate that given the thermodynamic tendency of forming network defects like loops, the model can include such imperfections, enabling rheological properties to be used indirectly for the characterization of defect content. We outline general guidelines to extend the model to more intricate structures, enhancing our understanding of the structure-property relationship in complex transient polymer networks.

4.
Soft Matter ; 19(42): 8112-8123, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37846598

RESUMO

Nature employs spontaneous self-organization of supramolecular bonds to create complex matter capable of adaptation and self-healing. Accordingly, the self-sorting of unlike ligands towards a cooperative heteroleptic complex or narcistic homoleptic association in a mixed ligand system is frequently employed to form interchangeable stimuli-responsive complex geometries with a wide range of applications. This notion is however just rarely employed in the organization of polymer networks. In this paper, we report the free-formation of heteroleptic complexes between tetra-am poly(ethylene glycol) (tetraPEG) precursors functionalized either with pyridine (tetraPy) or phenanthroline (tetraEPhen). Among a wide range of studied metal ions, tetraPy could form a network only in combination with Pd2+, presumably with a square-planar geometry, highlighting the importance of complex strength and stability in forming gels with monodentate ligands. Also, mixed networks with tetraEPhen form only in combination with Pd2+ and Fe2+, with strengths surpassing those of individual components and stabilities incomparable to those of parent networks, indicative of heteroleptic complexation. Extensive rheological, UV-vis, and DFT simulation studies revealed the coexistence of different coordination geometries, with an octahedral arrangement prevailing in the presence of Fe2+ and a square-planar geometry in the presence of Pd2+. Therefore, this study offers new opportunities for the development of stimuli-responsive topology-switching polymer networks.

5.
Diagnostics (Basel) ; 13(5)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36899961

RESUMO

The concept of mizaj corresponds to the idea of personalized medicine and is the main diagnostic principle of Persian medicine (PM). This study aims to investigate diagnostic tools for the detection of mizaj in PM. In this systematic review of articles published before September 2022, articles were searched for in the Web of Science, PubMed, Scopus, Google Scholar, SID databases, and gray literature. The titles of the articles were screened by researchers and relevant articles were selected. Abstracts were reviewed by two reviewers to select final articles. Subsequently, the articles found were critically evaluated by two reviewers according to the CEBM method. Finally, article data were extracted. Of the 1812 articles found, 54 were included in the final evaluation. Of these, 47 articles were related to the diagnosis of whole body mizaj (WBM). WBM was diagnosed in 37 studies using questionnaires and 10 using expert panels. In addition, six articles examined the mizaj of organs. Only four of these questionnaires were found with reported reliability and validity. There were two questionnaires for assessing WBM, but neither had sufficient reliability and validity. Questionnaires that assess organs had weak designs and lacked sufficient reliability and validity.

6.
J Infect Chemother ; 29(3): 250-256, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36414196

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus-2 raised in 2019 (COVID-19) affects the lung tissue and other organs, specifically the heart. METHODS: The current study evaluated 120 hospitalised patients with severe COVID-19 between March 2021 and February 2022. Patients' demographics, vital signs, electrocardiogram abnormalities, clinical laboratory tests, including troponin I (TPI), mortality, and discharge type, were recorded. RESULTS: Among the 120 hospitalised patients with severe COVID-19, 54 (45.0%) patients were male, with an average age of 63.2 ± 1.4. Many patients have chronic comorbidities, including hypertension (51.6%), diabetes mellitus (34.1%), and ischemic heart disease (17.5%). The in-hospital and six months after the discharge mortality were 45.8% and 21.5%, respectively. Cardiac injury was observed in 14 (11.7%) patients with a mean TPI level of 8.386 ± 17.89 µg/L, and patients with cardiac injury had higher mortality than those without cardiac injury (P < 0.001). Furthermore, the cardiac injury was meaningfully correlated with age (ρ = 0.182, P = 0.019), history of ischemic heart disease (ρ = 0.176, P = 0.05), hospitalisation result and mortality (ρ = 0.261, P = 0.004), inpatient in ICU (ρ = 0.219, P = 0.016), and serum levels of urea (ρ = 0.244, P = 0.008) and creatinine (ρ = 0.197, P = 0.033). Additionally, the discharge results were significantly correlated with oxygen saturation with (ρ = -0.23, P = 0.02) and without (ρ = -0.3, P = 0.001) oxygen therapy, D-dimer (ρ = 0.328, P = 0.019), LDH (ρ = 0.308, P = 0.003), urea (ρ = 0.2, P = 0.03), and creatinine (ρ = 0.17, P = 0.06) levels. CONCLUSION: Elevated TPI levels are associated with increased mortality in severe COVID-19 patients. Therefore, TPI may be a beneficial biofactor for early diagnosis of cardiac injury and preventing a high mortality rate.


Assuntos
COVID-19 , Traumatismos Cardíacos , Isquemia Miocárdica , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Troponina I , Mortalidade Hospitalar , Creatinina , Estudos Retrospectivos
7.
Physiol Rep ; 10(22): e15513, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36394077

RESUMO

The association between uric acid (UA) and cardio-metabolic conditions has been recognized for a long time. However, recently, a body of evidence has highlighted the independent role of UA in a series of conditions, including renal and cardiovascular diseases. In this light, data regarding the prognostic role of UA in acute coronary syndrome (ACS) is scarce. A total number of 100 patients, 59 males and 41 females, diagnosed with ACS were recruited in this study. At the time of admission to the hospital, the serum level of UA was measured. In addition, the HEART score was calculated based on each patients' profile. Participants were on average 61.37 ± 12.08 years old. The most prevalent risk factors were hypertension (48%), a history of coronary artery disease (40%), and diabetes mellitus (33%). The average serum level of UA was 5.81 ± 1.81 mg/dl, and the calculated HEART score had a median of six (minimum of two and maximum of ten). A positive yet statistically insignificant correlation was found between the measured UA level and the calculated HEART score (R = 0.375, p = 0.090). However, further studies with larger sample size are required to assess the direct association of UA level with major adverse cardiac events in patients with cardiovascular disease.


Assuntos
Síndrome Coronariana Aguda , Doença da Artéria Coronariana , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Síndrome Coronariana Aguda/complicações , Ácido Úrico , Fatores de Risco , Prognóstico
8.
Clin Case Rep ; 10(8): e6147, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35937014

RESUMO

Unroofed coronary sinus (UCS) is an uncommon congenital heart anomaly and the most unusual type of atrial septal defect. This report presents a 71-year-old female with palpitation and dyspnea following an emotional stress, who was referred for ablation of typical atrial flutter. Finally diagnosed with a partially unroofed CS causing a bidirectional shunt.

9.
Soft Matter ; 18(36): 6836-6847, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36040244

RESUMO

Byssus threads of mussels have high resistance against abrasion in wave-swept habitats because of their outer cuticle, which is rich in amino acid dopa complexes with Fe3+ ions. This stems from the transient nature of metal-ligand complexes that creates extra relaxation mechanisms. Inspired by this concept, in this work, supramolecular hydrogels based on poly(acrylic acid) functionalized with nitrocatechol groups are synthesized. Polymer chains are physically crosslinked via nitrocatechol-Fe3+ complexes. The hydrogels have different polymer volume fractions as well as different nitrocatechol : Fe3+ molar ratios. The strength of the supramolecular crosslinks strongly depends on the pH of the medium. The dynamics of these hydrogels are studied by stress relaxation experiments followed by calculation of the relaxation time spectrum. Generally, samples have three relaxation modes, including dissociation of distinct metal-ligand complexes, reptation of sticky polymer chains, and disengagement of network segments from supramolecular aggregates and clusters. Such clusters hinder the terminal relaxation and potentially increase the stability of supramolecular hydrogels.


Assuntos
Complexos de Coordenação , Hidrogéis , Catecóis , Análise por Conglomerados , Di-Hidroxifenilalanina/química , Hidrogéis/química , Íons , Ligantes , Metais , Nitrocompostos , Polímeros
10.
Pathogens ; 11(6)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35745471

RESUMO

BACKGROUND: SARS-CoV virus infection results in a dysbalanced and severe inflammatory response with hypercytokinemia and immunodepression. Viral infection triggers systemic inflammation and the virus itself can potentially cause vascular damage, including blood-brain barrier (BBB) disruption and alterations in the coagulation system, which may result in cardiovascular and neurovascular events. Here, we review the literature and present a case of COVID-19 infection leading to an aneurysmal subarachnoid haemorrhage (aSAH). CASE DESCRIPTION: A 61-year-old woman presented with dyspnea, cough, and fever. She had a history of hypertension and was overweight with a body mass-index of 34. There was no history of subarachnoid hemorrhage in the family. Due to low oxygen saturation (89%) she was admitted into ICU. A chest CT showed a typical picture of COVID-19 pneumonia. The PCR-based test of an oropharyngeal swab was COVID-19-positive. In addition to oxygen support she was prescribed with favipiravir and hydroxychloroquine. She experienced a sudden headache and lost consciousness on the second day. Computer tomography (CT) with CT-angiography revealed a subarachnoid haemorrhage in the basal cisterns from a ruptured anterior communicating artery aneurysm. The aneurysm was clipped microsurgically through a left-sided standard pterional approach and the patient was admitted again to the intensive care unit for further intensive medical treatment. Post-operatively, the patient showed slight motor dysphasia. No other neurological deficits. CONCLUSION: Systemic inflammation and ventilator support-associated blood pressure fluctuations may trigger aneurysmal subarachnoid haemorrhage secondary to COVID-19 infection. COVID-19 infection could be considered as one of the possible risk factors leading to instability and rupture of intracranial aneurysm.

11.
Soft Matter ; 18(5): 1071-1081, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35029258

RESUMO

Hydrogels are polymer networks swollen in water; they are suitable materials for biomedical applications such as tissue engineering and drug delivery. In the latter, the controlled diffusion of small diffusants inside the network is essential, as it determines the release mechanism of the drug. In general, the diffusion inside a polymer network is controlled by its mesh-size. Here, we actively control the diffusivity and also the softness of metallo-supramolecular hydrogels via the network mesh-topology by introducing connectivity defects. A model polymer network is realized based on a 4-arm poly(ethylene glycol) (pEG) where each arm is capped with terpyridine moieties that are capable of forming metallo-supramolecular complexes with zinc ions. In this model network, we insert 8-arm pEG macromolecules that are functionalized with terpyridine at different ratios to create connectivity defects. With an increasing amount of 8-arm pEG, the polymer network forms more loops, as quantified by double quantum-NMR. This doped network shows an enhanced self-diffusivity of the building block molecules within the network, as examined by fluorescence recovery after photobleaching, and a higher softness, as investigated by oscillatory shear rheology. With these findings, we show that it is possible to tune the diffusivity and softness of hydrogels with defects in a rational fashion.

12.
Inflammopharmacology ; 29(5): 1379-1387, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34420187

RESUMO

Myocardial infarction without ST-segment elevation (NSTEMI) is considered an inflammatory disorder associated with a high mortality rate worldwide. High-sensitivity C-reactive protein (hs-CRP) is an important inflammatory marker for NSTEMI and related to cardiovascular events. Colchicine, as a potent anti-inflammatory drug, is frequently prescribed for the treatment of gout and pericarditis. The present study aimed to evaluate the effects of colchicine, as an anti-inflammatory drug, on hs-CRP levels in NSTEMI patients. We performed a randomised, double-blind, placebo-controlled trial involving 150 NSTEMI patients referred to Imam Reza and Ghaem Hospitals affiliated to Mashhad University of Medical Sciences. The patients were randomised to receive colchicine or placebo along with optimal medications for 30 days. The hs-CRP was measured at the admission and end of the study. Our results revealed that, in both colchicine and placebo groups, hs-CRP levels were significantly mitigated in NSTEMI patients compared to baseline (P < 0.001). However, the decreasing properties of colchicine on hs-CRP levels were remarkably stronger than placebo following the 30 days of treatment (P < 0.001). Nevertheless, neither colchicine nor placebo treatment could achieve hs-CRP levels lower than 2 mg/L. There were no significant differences between the effects of colchicine on the hs-CRP decrease in diabetic and non-diabetic, male and female, and normal and preserved LVEF NSTEMI patients. It can be concluded that colchicine may prevent the disease progression and succedent cardiovascular events in NSTEMI patients by attenuating the inflammation.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colchicina/uso terapêutico , Infarto do Miocárdio sem Supradesnível do Segmento ST/tratamento farmacológico , Adulto , Idoso , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Progressão da Doença , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Inflamação/tratamento farmacológico , Inflamação/fisiopatologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio sem Supradesnível do Segmento ST/fisiopatologia
13.
Soft Matter ; 17(4): 955-964, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33284938

RESUMO

Biological materials employ a variety of dynamic interactions in sophisticated composite structures to function adaptively on different time and length scales. Inspired by such designs we develop a novel surface modification approach to promote dynamic interactions between nanoparticles and polymer chains in physical and double network hydrogels. Physical hydrogels are formed via reversible complexation of borate ions with poly(vinyl alcohol) (PVA) and chemical crosslinks are introduced by electron beam irradiation. Dopamine is used for surface modification of magnetic iron oxide nanoparticles (MNPs) in two different ways: the direct treatment results in anchoring via catechol groups, whereas the indirect method leaves the catechol group on the free surface of MNPs. Although the former particles show very good colloidal stability, they lower the network connectivity, which results in lower plateau modulus, faster terminal relaxation, and lower yield stress, presumably due to imposing an extra distance between PVA chains. In contrast to this passive design, the latter particles actively reinforce the network by forming clusters of physical bonds between catechol groups of the individual particles and the monodiol complexes of the borate ions and PVA chains. Moreover, the additional complexes formed upon the introduction of nanoparticles with active surfaces provide further energy dissipation potential and therefore enhance the toughness. This approach can help develop novel hydrogels with superior toughness and multiple stimuli-responsiveness.

14.
Phys Chem Chem Phys ; 22(26): 14965-14975, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32588852

RESUMO

The periodic change of the oxidation state of the metal catalyst in the oscillating Belousov-Zhabotinsky (BZ) reaction has been reported to establish a periodic organization of metallo-supramolecular bonds in polymeric systems, which results in autonomous viscosity oscillations. To appraise the possible extent of quantitative control on the viscosity oscillation features, we assess how the kinetics of the BZ reaction affects the periodic self-organization of the metal-ligand coordination, and vice versa. Our model system includes mono-, bis-, and tetra-functional polyethyleneglycol (PEG) precursors end grafted with terpyridine ligands that are complexed with ruthenium ions, which oscillate between Ru2+ and Ru3+ oxidation states in the BZ reaction medium. The control parameters are divided into microscopic factors, which are responsible for the local reaction rate, and mesoscopic factors, which are responsible for the spatial distribution of the concentration patterns. The reactant concentrations are found to nonlinearly control the amplitude and periods of reduction and oxidation phases, independent of the precursor functionalization degree. An increased medium viscosity, and therewith cease of mixing, accelerates the reaction rate by localization of the reaction phases, even though the diffusion of reaction intermediates causes a periodic chemical wave with distinct harmonics. Time-course viscosity measurements of the tetra-arm precursors in the BZ medium demonstrate an initial overshoot followed by minor oscillations around a plateau that is significantly lower than the viscosity of an equivalent fully associated network. Apparently, the slow association kinetics of Ru2+-bis(terpyridine) limits the frequency and the extent of self-organization, and this way, avoids full establishment of the expected viscosity oscillation.

15.
Soft Matter ; 16(9): 2332-2341, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32053126

RESUMO

Modern polymeric hydrogels use reversible bonds to mimic biological functionalities. However, true biological materials benefit from several supramolecular elements and deliver multiple functions at the same time. To approach similar creation and control of multiple different functional elements in a synthetic soft material, we develop a model dual-network hydrogel in which multiple energy dissipating modes are formed by metal-ligand coordination and regulated by their association thermodynamics. This idea is realized by using linear and tetra-arm poly(ethylene glycol) (PEG) precursors with complementary reactive end groups. The former also carries terpyridine ligands on both ends, which form metallo-supramolecular bonds upon addition of metal ions. Multiple relaxation modes are provided by a combination of different metal ions. The timescale and amplitude of energy dissipating elements are characterized by oscillatory shear deformation. These studies suggest that the composition of metal ions controls the contribution of the corresponding relaxation modes in a linear fashion. A molecular-level confirmation is provided by following the UV-vis absorbance of the linear precursor in combination with mixtures of metal ions, accompanied by a theoretical study on the kinetics of the reversible association process. These results show that the linearity of the aforementioned dependence holds for such systems in which the utilized combination of metal ions and ligands exclusively form stable bis-complexes. By contrast, in many other cases, especially when the ions may compete to form mono-, bis-, or tris-complexes with the ligand, deviation from linearity is expected.

16.
Afr Health Sci ; 20(3): 1241-1249, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33402971

RESUMO

BACKGROUND: Polycystic Ovarian Syndrome (PCOS) is one of the most common causes of infertility in women. OBJECTIVE: The current study investigated mental and personality disorders in infertile women with and without PCOS. METHODS: This case-control study evaluated 400 infertile women who referred to the Infertility Center in Babol city (North of Iran). Participants were categorized into the case group (201 PCOS) and the control group (199 without PCOS). All of the participants completed the Millon Clinical Multi-axial Inventory-III (MCMI-III). RESULTS: The mean scores for clinical personality patterns were significantly higher for six personality disorders (schizoid, avoidant, antisocial, depressive, sadistic, and negativistic) and for three classes of severe personality disorder patterns (schizotypal, borderline, and paranoid) in infertile women with PCOS than in women without PCOS. The mean scores for eight clinical disorders (somatoform, manic disorder, dysthymia, alcohol-dependence, drug-dependence, post-trauma stress disorder, major depression, and delusion disorder) were also higher in infertile women with PCOS than in women without PCOS. CONCLUSION: The scores of many mental and personality disorders are higher in infertile women with PCOS than in women without PCOS. Thus, clinicians should prioritize recognizing and treating psychological problems of infertile women with PCOS.


Assuntos
Ansiedade/psicologia , Infertilidade Feminina/psicologia , Transtornos da Personalidade/psicologia , Síndrome do Ovário Policístico/complicações , Qualidade de Vida/psicologia , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Infertilidade Feminina/etiologia , Irã (Geográfico) , Transtornos Mentais/complicações , Pessoa de Meia-Idade , Síndrome do Ovário Policístico/psicologia , Adulto Jovem
17.
ARYA Atheroscler ; 15(4): 201-204, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31819754

RESUMO

BACKGROUND: Despite recent advances in diagnostic techniques in cardiology, electrocardiography (ECG) has yet remained the first and corner stone of detecting emergency cardiac events including myocardial infarction (MI). There are some ECG findings which are considered as equivalents to MI. De Winter ST-T wave pattern is one of the important ECG findings which is thought to be related to left anterior descending artery occlusion. However, the coexistence of this ECG pattern with other ECG abnormalities are not reported widely. In this report, we discussed a unique case of de Winter ST-T wave pattern in a patient with Wolff-Parkinson-White (WPW) syndrome for the first time. CASE REPORT: A 43-year-old man was referred because of an intermittent typical chest pain. The patient had no cardiovascular risk factor, and was not on any medication; laboratory tests showed elevated and raising troponin I. The first ECG showed pre-excitation (WPW) as well as de winter pattern. According to patient's symptoms and suggestive ECG for probable left anterior descending (LAD) occlusion, emergent angiography was scheduled. The coronary angiography revealed sever LAD artery occlusion. The patient was symptom free after successful percutaneous coronary intervention, and was discharged on medication. The patient remained asymptomatic in 1-year follow-up period. CONCLUSION: Presence of de Winter ST-T changes with other ECG abnormalities is a rare issue, and here we addressed the first case of WPW and de Winter. The physicians should be aware that ECG changes in patients with WPW should not be interpreted as de Winter ST-T changes and vice versa.

18.
Phys Chem Chem Phys ; 21(35): 19623-19638, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31465047

RESUMO

The dynamics of supramolecular polymer assemblies is governed by that of their polymeric building blocks and that of the transient bonds between them. Entrapment of such bonds by topological crowding often causes renormalization of the bond lifetimes towards prolonging. In the present study, by contrast, we show that this effect can also be inverse in the case of telechelic metallo-supramolecular polymers in semi-dilute solution. We focus on linear poly(ethylene glycols) capped by terpyridine binding motifs at both ends that can form metal-ligand coordinative bonds with various transition metal ions, thereby creating transient metallo-supramolecular assemblies of varying length and binding strength. Oscillatory shear rheology measurements along with theoretical modelling of the mechanical spectra of these samples reveals a pronounced enhancement of the complex dissociation kinetics that is dependent on the length of the polymeric chain segment, with longer segments yielding faster dissociation times up to six orders of magnitude shorter than described for the free complexes. This finding indicates that the dynamic activity of the polymer chain itself causes complex destabilization.

19.
Cardiovasc Revasc Med ; 20(7): 583-587, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30232022

RESUMO

BACKGROUND: In-stent restenosis (ISR) is one adverse outcome of coronary stent implantation. Although using drug-eluting stents has reduced the rate of ISR, it remains a major problem. Here, we have investigated the relationship between several patient characteristics including serum high sensitive C-reactive protein (hs-CRP) and ISR. METHODS: This was a case-control study comprising 104 individuals with ISR and 202 patients without. Baseline characteristics were collected using a questionnaire. Fasting blood glucose (FBG), serum triglycerides (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and serum high sensitivity C-reactive protein (hs-CRP) were measured using commercial kits on an auto-analyzer. Data were analyzed using SPSS software and a p value ≤ 0.05 was considered significant. RESULTS: Diabetes mellitus (p < 0.001), stent type (p = 0.005), serum hs-CRP (p = 0.006), FBG (p = 0.038) and serum TG (p = 0.039) were significantly associated with ISR. The association between hs-CRP and ISR remained significant after adjustment for stent type and DM. For patients with a serum hs-CRP <2.64 mg/dL, ISR was only associated with diabetes mellitus (p = 0.016); while for individuals with a serum hs-CRP ≥2.64 mg/dL, ISR was also associated with the presence of diabetes mellitus, serum triglycerides and stent type. CONCLUSION: Higher levels of serum hs-CRP were significantly associated with the occurrence of ISR.


Assuntos
Proteína C-Reativa/análise , Doença da Artéria Coronariana/terapia , Reestenose Coronária/etiologia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/instrumentação , Stents , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico por imagem , Reestenose Coronária/sangue , Reestenose Coronária/diagnóstico , Diabetes Mellitus , Feminino , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Desenho de Prótese , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Regulação para Cima
20.
Int Med Case Rep J ; 11: 205-208, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30233255

RESUMO

Pulmonary prosthetic valve thrombosis is a serious and rare complication with high mortality. Using reteplase for treatment of prosthesis thrombosis is rarely reported. We report the first case in Iran of a thrombosed pulmonary valve in a patient who had undergone repair of tetralogy of Fallot, which was successfully treated twice with intravenous thrombolytic therapy with reteplase.

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