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A series of two-electron-oxidized cobalt porphyrin dimers have been synthesized upon controlled oxidations using halogens. Rather unexpectedly, X-ray structures of two of these complexes contain two structurally different low-spin molecules in the same asymmetric unit of their unit cells: one is the metal-centered oxidized diamagnetic entity of the type CoIII(por), while the other one is the ligand-centered oxidized paramagnetic entity of the type CoII(porâ¢+). Spectroscopic, magnetic, and DFT investigations confirmed the coexistence of the two very different electronic structures both in the solid and solution phases and also revealed a ferromagnetic spin coupling between Co(II) and porphyrin π-cation radicals and a weak antiferromagnetic coupling between the π-cation radicals of two macrocycles via the bridge in the paramagnetic complex.
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Three cyano-coordinated cobalt porphyrin dimers were synthesized and thoroughly characterized. The X-ray structure of the complexes reveals that cyanide binds in a terminal fashion in both the anti and trans isomers of ethane- and ethylene-bridged cobalt porphyrin dimers, while in the cis ethylene-bridged dimer, cyanides bind in both terminal and bridging modes. The nonconjugated ethane-bridged complex stabilizes exclusively a diamagnetic metal-centered oxidation of type CoIII(por)(CN)2 both in the solid and in solution. In contrast, the complexes with the conjugated ethylene-bridge contain signatures of both paramagnetic ligand-centered oxidation of the type CoII(porâ¢+)(CN)2 and diamagnetic metal-centered oxidation of type CoIII(por)(CN)2 with the metal-centered oxidized species being the major component in the solid state as observed in XPS, while the ligand-centered oxidized species are present in a significant amount in solution. 1H NMR spectrum in solution displays two set of signals corresponding to the simultaneous presence of both the diamagnetic and paramagnetic species. EPR and magnetic investigation reveal that there is a moderate ferromagnetic coupling between the unpaired electrons of the low-spin CoII center and the porphyrin π-cation radical in CoII(porâ¢+)(CN)2 species as well as an antiferromagnetic coupling between the two CoII(porâ¢+) units through the ethylene and CN bridges.
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A cobalt porphyrin dimer is constructed in which two Co(II)porphyrins are connected covalently through a redox-active diethylpyrrole moiety via a flexible but "nonconjugated" methylene bridge. Upon oxidation with even a mild oxidant such as iodine, each cobalt(II) center and porphyrin ring undergo 1e- oxidation, leading to the formation of a 4e--oxidized cobalt(III)porphyrin dication diradical complex. Other oxidants such as Cl2 and Br2 also produce similar results. To stabilize such highly oxidized dication diradicals, the "nonconjugated" methylene spacer undergoes a facile and spontaneous oxidation to form a methine group with a drastic structural change, thereby making the bridge fully π-conjugated and enabling through-bond communication. This results in a strong spin coupling between two π-cation radicals which stabilizes the singlet state. The experimental observations are also strongly supported by extensive density functional theory calculations. The present study highlights the crucial role played by the nature of the bridge in the long-range electronic communication.
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Dinickel(II) and dicopper(II) porphyrin dimers have been constructed in which two metalloporphyrin units are widely separated by a long unconjugated dipyrrole bridge. Two macrocycles are aligned somewhat orthogonally to each other, while oxidation of the bridge generates a fully π-conjugated butterfly-like structure, which, in turn, upon stepwise oxidations by stronger oxidants result in the formation of the corresponding one- and two-electron-oxidized species exhibiting unusual long-range charge/radical delocalization to produce intense absorptions in the near-infrared (NIR) region and electron paramagnetic resonance (EPR) signals of a triplet state due to interaction between the unpaired spins on the Cu(II) ions. Although the two metal centers have a large physical separation through the bridge (more than 16 Å), they share electrons efficiently between them, behaving as a single unit rather than two independent centers. Detailed UV-vis-NIR, electrospray ionization mass spectrometry, IR, variable-temperature magnetic study, and EPR spectroscopic investigations along with X-ray structure determination of unconjugated, conjugated, and one electron-oxidized complexes have been exploited to demonstrate the long-range electronic communication through the bridge. The experimental observations are also supported by density functional theory (DFT) and time-dependent DFT calculations. The present study highlights the crucial roles played by a redox-active bridge and metal in controlling the long-range electronic communication.
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Metais , Cristalografia por Raios X , Íons , Ligantes , OxirreduçãoRESUMO
Limited availability of medical imaging datasets is a vital limitation when using "data hungry" deep learning to gain performance improvements. Dealing with the issue, transfer learning has become a de facto standard, where a pre-trained convolution neural network (CNN), typically on natural images (e.g., ImageNet), is finetuned on medical images. Meanwhile, pre-trained transformers, which are self-attention-based models, have become de facto standard in natural language processing (NLP) and state of the art in image classification due to their powerful transfer learning abilities. Inspired by the success of transformers in NLP and image classification, large-scale transformers (such as vision transformer) are trained on natural images. Based on these recent developments, this research aims to explore the efficacy of pre-trained natural image transformers for medical images. Specifically, we analyze pre-trained vision transformer on CheXpert and pediatric pneumonia dataset. We use CNN standard models including VGGNet and ResNet as baseline models. By examining the acquired representations and results, we discover that transfer learning from the pre-trained vision transformer shows improved results as compared to pre-trained CNN which demonstrates a greater transfer ability of the transformers in medical imaging.
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Aprendizado de Máquina , Redes Neurais de Computação , Humanos , Criança , RadiografiaRESUMO
We have described copper(II)-iron(III) and copper(II)-manganese(III) heterobimetallic porphyrin dimers and compared them with the corresponding homobimetallic analogs. UV-visible spectra are very distinct in the heterometallic species while electrochemical studies demonstrate that these species, as compared to the homobimetallic analog, are much easier to oxidize. Combined Mössbauer, EPR, NMR, magnetic and UV-visible spectroscopic studies show that upon 2e-oxidation of the heterobimetallic complexes only ring-centered oxidation occurs. The energy differences between HOMO and LUMO are linearly dependent with the low-energy NIR band obtained for the 2e-oxidized complexes. Also, strong electronic communication between two porphyrin rings through the bridge facilitates coupling between various unpaired spins present while the coupling model depends on the nature of metal ions used. While unpaired spins of Fe(III) and the porphyrin π-cation radical are strongly antiferromagnetically coupled, such coupling is rather weak between Mn(III) and a porphyrin π-cation radical. Moreover, the coupling between two π-cation radicals are much stronger in the 2e-oxidized complexes of dimanganese(III) and copper(II)-manganese(III) porphyrin dimers as compared to their diiron(III) and copper(II)-iron(III) analogs. Furthermore, coupling between the unpaired spins of a π-cation radical and copper(II) is much stronger in the 2e-oxidized complex of copper(II)-iron(III) porphyrin dimer as compared to its copper(II)-manganese(III) analog. The Mulliken spin density distributions in 2e-oxidized homo- and heterobimetallic complexes show symmetric and asymmetric spread between the two macrocycles, respectively. In both the 2e-oxidized heterobimetallic complexes, the Cu(II) porphyrin center acts as a charge donor while Fe(III)/Mn(III) porphyrin center act as a charge acceptor. The experimental observations are also strongly supported by DFT calculations.
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Compostos Férricos , Porfirinas , Ferro , Espectroscopia de Ressonância Magnética , OxirreduçãoRESUMO
Three different oxidovanadium(IV) porphyrin dimers with anti, cis, and trans arrangements of the two rings have been synthesized by changing the bridge between the porphyrin macrocycles. This provides a unique opportunity to investigate the role of the bridge and spatial arrangement between the two VIVO centers for their electronic communication and magnetic coupling. They were characterized by the combined application of XRD analysis, UV-vis and electron paramagnetic resonance (EPR) spectroscopy, cyclic voltammetry, magnetic susceptibility, and DFT calculations. One- and two-electron oxidations produce mono- and dication diradical species, respectively, which display an unusual ferromagnetic interaction between the unpaired spins of vanadium(IV) and porphyrin π-cation radical, in contrast to other metalloporphyrin dimers. The oxidized species show a dissimilar behavior between cis and trans isomers. The ferromagnetic coupling occurs between the porphyrin π-cation radical and the unpaired electron of the VIVO ion on the dxy orbital, orthogonal to the porphyrin-based molecular orbitals a1u and a2u.
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For the first time, fully characterized and stable trinuclear "double sandwich" molecules are reported with Hg(II) ion using a highly flexible porphyrin dimer. The molecules display interesting and intense luminescence properties at room temperature. The present investigation clearly demonstrates that attractive mercurophilic interactions do play an essential role in bringing two porphyrin macrocycles exactly on top of each other with an unfavorable fully eclipsed geometry to produce short Hg···Hg distances. Interactions between Hg(II) dz2 orbitals provide the directionality with a linear Hg3 core having short Hg···Hg distances despite the fact that ligand framework is highly flexible.
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Two polymorphs of a new cesium ferrogermanate zeotype, CsFeGeO4, were synthesized using the molten CsCl-CsF flux growth approach at 900 °C. The orthorhombic polymorph, referred to as (1), crystallizes in the centrosymmetric nonpolar Pbcm space group. The compound exhibits a three-dimensional porous framework structure composed of disordered (Fe/Ge)O4 corner-sharing tetrahedra that generate large eight-sided channels running down the b-axis. These channels are occupied by Cs ions that provide charge balance to the anionic framework. Minor modifications in the reaction conditions lead to the synthesis of a monoclinic polymorph of CsFeGeO4, referred to as (2), crystallizing in the noncentrosymmetric polar space group P21 and exhibiting an identical framework structure to (1), albeit featuring ordered FeO4 and GeO4 tetrahedra. Solid state synthesis of CsFeGeO4 produces a polycrystalline mixture of (1) and (2), referred to as (6). Polarization-electric field (P-E) measurements of (6) indicate that the material is not ferroelectric. Powder second harmonic generation (SHG) measurements of (2) and (6) revealed them to be SHG active with intensities of 1.5 and 0.2 times that of α-SiO2, respectively. The temperature dependent magnetic susceptibility of (2) exhibits a downturn at T = 2.6 K, indicative of antiferromagnetic ordering. First-principles calculations in the form of density functional theory showed that (1) and (2) differ in stability by only 1.3 meV/atom, with (2) being the thermodynamically stabilized phase. Additional calculations for (1), using molten nitrate as reference, predicted the formation of energetically favorable phases, KFeGeO4 (3) and RbFeGeO4 (4). They were subsequently prepared via a molten nitrate salt bath treatment of (1) to replace Cs with K and Rb, affording (3) and (4) as single-crystal to single-crystal ion exchange products. Structure determination and property measurements for a pyroxene phase, CsFeGe2O6, referred to as (5), are also reported. This compound crystallized as a side product in the flux synthesis of CsFeGeO4.
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Cupric ions are hazardous to human beings and their removal from the body is very necessary. The blends of IRP69H (AMBERLITE IRP-69 [H+] RESIN), DC20H (DOWEX™ 20 [H+] Resin), DMSCH (DOWEX™ MARATHON™ MSC [H+] Resin) and Kappa Carrageenan (κ-) were utilized for the removal of ions of Cu2+ from the blood. They were subjected to docking studies which showed that there is no significant interaction with the blood albumin. IER dose of 0.5 mg/10mL of IRP69H/κ-, DMSCH/κ-, and DC20H/κ- was essential for the 2+ ion removal. At pH 5.4, optimal 2+ ions adsorption efficiency was attained. The adsorption capacities of 2+ were in the order of IRP69H/κ->DC20H/κ->DMSCH/κ-. While the data fitted well to Freundlich, Langmuir and Dubinin-Radushkevich. Pseudo-second order was followed for 2+ adsorption for DMSCH/κ- and DC20H/κ- while the pseudo-first order was demonstrated well for IRP69H/κ-.
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Carragenina/química , Cobre/química , Resinas de Troca Iônica/química , Íons/química , Adsorção , Adulto , Humanos , Concentração de Íons de Hidrogênio , Cinética , Resinas Sintéticas/química , Termodinâmica , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adulto JovemRESUMO
Metallophilic interactions between closed-shell metal ions are becoming a popular tool for a variety of applications related to high-end materials. Heavier d8 transition-metal ions are also considered to have a closed shell and can be involved in such interactions. There is no systematic investigation so far to estimate the structure and energy characteristics of metallophilic interactions in AgII /AgII (d9 /d9 ), AgIII /AgIII (d8 /d8 ), and mixed-valent AgII /AgIII (d9 /d8 ) complexes, which have been demonstrated in the present study. Both interporphyrinic and intermetallic interactions were investigated on stepwise oxidation by using a rigid ethene-bridged cis silver(II) porphyrin dimer and the results compared with those for highly flexible ethane-bridged analogues. By controlling the nature of chemical oxidants and their stoichiometry, both 1e and 2e oxidations were done stepwise to generate AgII /AgIII mixed-valent and AgIII /AgIII porphyrin dimers, respectively. Unlike all other ethene-bridged metalloporphyrin dimers reported earlier, in which 2e oxidation stabilizes only the trans form, such an oxidation of silver(II) porphyrin dimer stabilizes only the cis form because of the metallophilic interaction. Besides silver(II)â
â
â
silver(II) interactions in cis silver(II) porphyrin dimer, stepwise oxidations also enabled us to achieve various hitherto-unknown silver(II)â
â
â
silver(III) and silver(III)â
â
â
silver(III) interactions, which thereby allow significant modulation of their structure and properties. The strength of Agâ
â
â
Ag interaction follows the order AgII /AgII (d9 /d9 )
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Twenty new alkali rare earth thiosilicates and thiogermanates with the general formula ALnTS4 (A = alkali metal, Ln = lanthanide, and T = Si, Ge) were grown as X-ray diffraction-quality single crystals from molten alkali chloride fluxes. These include KNdSiS4, KPrSiS4, RbLnSiS4 (Ln = Ce, Pr, Nd, Gd, Tb, Dy, and Ho), RbLaGeS4, CsLnSiS4 (Ln = La, Pr, and Nd), and CsLnGeS4 (La, Ce, Pr, Nd, Eu, Gd, and Tb). Herein, we discuss the use of a molten chloride flux growth approach for the preparation of the title compounds and their structure determination via single-crystal X-ray diffraction. In addition, we comment on the magnetic properties of RbNdSiS4, CsNdSiS4, CsNdGeS4, and CsGdGeS4, which were found to be paramagnetic for T = 2-300 K and exhibited negative Weiss temperatures with no obvious antiferromagnetic transition down to 2 K. The optical properties of CsLaGeS4 and CsNdTS4(T = Si, Ge) were measured by UV-vis spectroscopy. Second harmonic generation measurements performed on CsLaGeS4 confirmed the crystallization of the compound in the noncentrosymmetric orthorhombic space group, P212121; CsLaGeS4 was found to be SHG-active with nearly half the intensity of α-SiO2 upon irradiation with a Nd:YAG 1064 nm laser, and a semiconductor exhibiting a band gap of 3.60 eV based on UV-vis diffuse reflectance measurements.
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INTRODUCTION: A hip fracture carries significant morbidity and mortality-a second fracture of the contralateral hip carries even higher complications. Most second hip fractures occur within 48 months of the first. The aim of this study was to comprehensively analyse all identifiable variables that may increase the risk of a contralateral hip fracture within this time period. METHODS: We retrospectively analysed 1242 consecutive patients with hip fractures presenting to our institution. All patient-related, surgery-related and inpatient variables were collected from the index admission. We then identified patients with a subsequent contralateral hip fracture in the following 2 years. Univariate and multivariate analyses were performed to identify risk factors associated with a second fracture. RESULTS: A total of 66 patients (5.3%) had a contralateral hip fracture in the 2 years following initial hip fracture. Mean age at first presentation was 81 years, and mean time to second fracture was 305 days. Following multivariate analysis, the patients at highest risk of a second fracture were those with dementia, acute inpatient chest infection, urinary tract infection and multiple comorbidities as measured by the Charlson score. Discharge destination after initial fracture was not associated with the risk of a second fracture. CONCLUSIONS: We have identified a number of discrete risk factors that are associated with a short- to medium-term risk of contralateral hip fracture that may be useful in screening for patients at risk and provide them with focused medical rehabilitation.
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Demência/epidemiologia , Fixação de Fratura , Fraturas do Quadril , Fraturas por Osteoporose , Readmissão do Paciente/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Fixação de Fratura/efeitos adversos , Fixação de Fratura/métodos , Idoso Fragilizado/estatística & dados numéricos , Fraturas do Quadril/diagnóstico , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/cirurgia , Humanos , Masculino , Múltiplas Afecções Crônicas/epidemiologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/cirurgia , Período Pós-Operatório , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Reino Unido/epidemiologiaRESUMO
Harmine, Harmaline, Nicotine and its various complexes synthesized have been characterized by physical, spectral and analytical methods and curtained for in-vitro antimicrobial activity against different bacterial and fungal species at two different concentrations i.e.100µ/100µl and 200µ/100µl dose level respectively. Analysis showed that Nicotine, Zinc-Nico, Cd-Nico, Hg-Nico, Ni-Nico, Cu-Nico, Co-Nico, Harmine, and Harmaline having conc. of 100ug/ 100ul had antibacterial activity on zero, 5, 4, 10, zero, 5, 7, zero, zero strain of bacteria having an average of zero (SD=0.0000), 15.2000 (SD=1.30384), 18.2500 (SD=3.30404), 20.2000 (SD=1.39841), zero (SD=0.0000), 14.6000 (SD=0.89443), 15.8571 (SD=1.34519), zero (SD=0.0000), zero (SD=0.0000) respectively. Zinc (II) chloride, Cadmium (II) Iodide, Mercury (II) chloride, Nickel (II) chloride, Copper (II) chloride, Cobalt (II) chloride, Mercury (II) chloride, Mercury (II) harmine, Mercury (II) harmaline at 100ug/100ul is valid for 7, 8, 9, 2, 7, 8, 9, 10, 8 strains of bacteria with an average of 7.1429 (SD=1.06904), 10.0000 (SD=5.01427), 14.8889 (SD=6.00925), 6.0000 (SD=0.0000), 8.5714 (SD=4.27618), 8.2500 (SD=0.88641), 14.8889 (SD=6.00925), 18.6000 (SD=2.45855), 18.5000 (SD=1.85164) respectively. The above given compounds at the conc. of 200 µ/100ul is valid for 10, 9, 10, 8, 8, 10, 10, 10, 10 strains of bacteria with an average of 8.1 (SD=1.66333), 11.7778 (SD=5.28625), 16.1000 (SD=6.36745), 6.5000 (SD=0.92582), 9.7500 (SD=4.43203), 9.9000 (SD=2.76687), 16.1000 (SD=6.36745), 22.0000 (SD=2.44949), 20.4000 (SD=2.75681) respectively. The above given compounds at conc. of 200 µ/100ul showed antibacterial action on 3, 8, 8, 10, 3, 9, 8, zero, 3 strains of bacteria with an average of 14(SD=0.000), 16.8750 (SD=1.35620), 18.2500 (SD=3.45378), 22.7000 (SD=1.82878), 14.3333 (SD=0.57735), 16.7778 (SD=1.71594), zero (SD=0.000), 12.0000 (SD=1.00000) respectively. Hence according to the average value of the zone of inhibition, maximum antibacterial activity at 100-200ug/100ul is of Hg-Nico and Mercury salt; Mercury (II) harmine having an average of 20.2000 (SD=1.39841)-22.7000 (SD=1.82878) and 18.6000 (SD=2.45855)-22.0000 (SD=2.44949). Minimum antibacterial activity at 100-200ug/100ul is Nicotine100, Nicotine-Nico100, Harmine 100,Harmaline 100, Harmine 200 having zero average (SD=0.000).
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Anti-Infecciosos/farmacologia , Harmalina/farmacologia , Harmina/farmacologia , Nicotina/farmacologiaRESUMO
As the number of surgical procedures performed the world over continues to increase, so does the number of anesthetic procedures needed for those surgeries to occur. While much thought and research has been focused on the perspective of the anesthesiologist, little has been explored from the perspective of the patient receiving anesthesia. The purpose of this study was to explore the general public's opinions and experiences of general anesthesia, as well as any change in their perception after having undergone a procedure requiring it. We decided that further inquiry into the subject was warranted, and we decided to run an online Qualtrics survey in order to make that inquiry. The key takeaway from our online anonymous survey shows that there is a significant amount of anxiety related to anesthesia, but that most people specify a large decrease in said anxiety after having undergone the procedure. Noticeably, people were made more comfortable by discussing anesthesia with people who had lived through the experience, and people believed they would be significantly comforted by the presence of therapy animals prior to beginning their procedures. We hope that our exploratory research will promote future research into this topic in order to improve the healthcare outcomes of a significant number of patients. We believe that this data has opened up many potential avenues for further exploration and research, as well as potentially being able to guide surgical practice.
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BACKGROUND: Current methods for monitoring ventilatory rate have limitations including poor accuracy and precision and low patient tolerance. In this study, we evaluated a new acoustic ventilatory rate monitoring technology for accuracy, precision, reliability, and the ability to detect pauses in ventilation, relative to capnometry and a reference method in postsurgical patients. METHODS: Adult patients presenting to the postanesthesia care unit were connected to a Pulse CO-Oximeter with acoustic monitoring technology (Rad-87, version 7804, Masimo, Irvine, CA) through an adhesive bioacoustic sensor (RAS-125, rev C) applied to the neck. Each subject also wore a nasal cannula connected to a bedside capnometer (Capnostream20, version 4.5, Oridion, Needham, MA). The acoustic monitor and capnometer were connected to a computer for continuous acoustic and expiratory carbon dioxide waveform recordings. Recordings were retrospectively analyzed by a trained technician in a setting that allowed for the simultaneous viewing of both waveforms while listening to the breathing sounds from the acoustic signal to determine inspiration and expiration reference markers within the ventilatory cycle without using the acoustic monitor- or capnometer-calculated ventilatory rate. This allowed the automatic calculation of a reference ventilatory rate for each device through a software program (TagEditor, Masimo). Accuracy (relative to the respective reference) and precision of each device were estimated and compared with each other. Sensitivity for detection of pauses in ventilation, defined as no inspiration or expiration activity in the reference ventilatory cycle for ≥30 seconds, was also determined. The devices were also evaluated for their reliability, i.e., the percentage of the time when each displayed a value and did not drop a measurement. RESULTS: Thirty-three adults (73% female) with age of 45 ± 14 years and weight 117 ± 42 kg were enrolled. A total of 3712 minutes of monitoring time (average 112 minutes per subject) were analyzed across the 2 devices, reference ventilatory rates ranged from 1.9 to 49.1 bpm. Acoustic monitoring showed significantly greater accuracy (P = 0.0056) and precision (P- = 0.0024) for respiratory rate as compared with capnometry. On average, both devices displayed data over 97% of the monitored time. The (0.95, 0.95) lower tolerance limits for the acoustic monitor and capnometer were 94% and 84%, respectively. Acoustic monitoring was marginally more sensitive (P = 0.0461) to pauses in ventilation (81% vs 62%) in 21 apneic events. CONCLUSIONS: In this study of a population of postsurgical patients, the acoustic monitor and capnometer both reliably monitored ventilatory rate. The acoustic monitor was statistically more accurate and more precise than the capnometer, but differences in performance were modest. It is not known whether the observed differences are clinically significant. The acoustic monitor was more sensitive to detecting pauses in ventilation. Acoustic monitoring may provide an effective and convenient means of monitoring ventilatory rate in postsurgical patients.
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Oximetria/normas , Cuidados Pós-Operatórios/normas , Taxa Respiratória/fisiologia , Som , Adulto , Monitorização Transcutânea dos Gases Sanguíneos/instrumentação , Monitorização Transcutânea dos Gases Sanguíneos/métodos , Monitorização Transcutânea dos Gases Sanguíneos/normas , Capnografia/instrumentação , Capnografia/métodos , Capnografia/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Monitorização Fisiológica/normas , Oximetria/instrumentação , Oximetria/métodos , Cuidados Pós-Operatórios/instrumentação , Cuidados Pós-Operatórios/métodos , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
The present study was designed to investigate the effect of Cedrus deodara root oil on the histopathology of different gastrointestinal organs of Wistar rats. This oil was used traditionally as an anti-ulcer agent in the Indus Unic System and extracted from the plant root by destructive distillation method. A total of 90 rats were taken and divided into groups A, B and C, each comprising of 30 animals. The animals of group B and C were given 0.5 ml/kg and 2.5 ml/kg of C. deodara oil respectively while group A served as control and administered vehicle only. The treatment was given to the animals ones only for 24 hours. All animals were sacrificed and the organs like esophagus, stomach and ileum were taken out. Tissue processing and staining procedure was then carried out for any pathological changes in the animal tissues during microscopic examination. The results indicated that Cedurs deodara root oil at both doses 0.5ml/ kg and 2.5 ml/kg exhibited some adverse effects such as erosion of epithelium, edema on sub-mucosal and mucosal layers, congestion of blood vessels as well as presence of inflammatory cells on esophagus, stomach and ileum were seen. Moreover shortening of villi was also seen at both doses. A study conducted on mammalian toxicity previously on rats revealed that the C. deodara root oil used is not very toxic and comes under least toxic group as standardized by toxicologists. Based on the results obtained it was concluded that C. deodara root oil produced some adverse changes in the tissues of GIT when given at 0.5 ml/kg and 2.5 ml/kg doses but the effects were not lethal therapeutically at this dose LC50 16.5 ml/kg. The plant oil showed some toxicity and needs further detailed studies to assess its potential toxicity and therapeutic status before using this material as drug.
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Cedrus/química , Trato Gastrointestinal/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Animais , Antiulcerosos/química , Antiulcerosos/farmacologia , Edema/tratamento farmacológico , Inflamação/tratamento farmacológico , Masculino , Raízes de Plantas/química , Ratos , Ratos WistarRESUMO
The COVID-19 pandemic brought immense attention to the healthcare system and its workers. While much research has been completed about the effects of COVID-19 on the healthcare system, little exists about how the opinions of patients have been altered by this pandemic. We decided to further investigate how the public opinion of healthcare workers (HCWs) has changed to better understand how best we can serve society. The key takeaway from the data was that both the levels of perceived trustworthiness and respectability of healthcare workers decreased following the pandemic. Data showed that the level of perceived respectability decreased from an average of 7.84 to 7.30 and the level of perceived trustworthiness from 7.38 to 6.54, all of these values out of 10. While these changes were not enormous, they demonstrate a striking trend and were found to be significant through a paired t-test. Finally, respondents were also queried about their level of desire in pursuing healthcare as a career field and overwhelmingly there was little interest, with an average level of 1.24 out of 10. We believe our data and results show important trends that all HCWs should be aware of; notably decreasing interest in the field, reduced trust, and decrease in respect, all of which will require further study and analysis. We must consider the current environment in which small mistakes or mistrust can have grave consequences on public health and patient compliance. In addition, the lack of interest in joining the medical community is concerning considering the large efflux of workers leaving the profession. Future studies could focus on how to increase trust in HCWs or attract more people to the healthcare field.
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A dinickel(II)porphyrin dimer has been used here in which the redox-active pyrrole-moiety, similar to the tryptophan residue in diheme enzymes such as MauG and bCcP, has been placed between two Ni(II)porphyrin centers connected via a flexible, but unconjugated methylene bridge. This arrangement provides a large physical separation between the two metal centers and thus displays almost no communication between them through the bridge. Upon treatment with DDQ as an oxidant, the dinickel(II) porphyrin dimer slowly gets converted into an indolizinium-fused chlorin-porphyrin heterodimer. However, oxidations of the dinickel(II) porphyrin dimer up to two oxidizing equivalents using oxidants such as AgSbF6 and FeCl3 resulted in the formation of a dication diradical complex. Interestingly, in order to stabilize such a highly oxidized dication diradical, two non-conjugated methylene spacers undergo facile 2e-/-2H+ oxidation to make the bridge fully π-conjugated for promoting through-bond communication. Through the oxidized and conjugated bridge, two porphyrin π-cation radicals display considerable communications leading to an efficient intramolecular spin coupling to form a singlet state. Interestingly, the redox-active nature of the bridge controls the electronic communication just by simple oxidation or reduction, and thereby, acts as a molecular switch for efficient magnetic relay.
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Porfirinas , Porfirinas/química , Oxirredução , Pirróis , Oxidantes , PolímerosRESUMO
Rheumatoid arthritis (RA) is a common autoimmune condition that can rarely cause more serious complications, such as permanent joint damage or infection, and may pose a significant additional risk during certain routine procedures. One major consequence of RA is that it can lead to serious and permanent joint damage requiring arthroplasty. Additionally, RA is a known cause of infection, with orthopedic prosthetic joint infections (PJIs) being documented. We explore one such serious case of a patient with long-term RA and a left knee joint replacement who presented to the emergency room with a serious PJI. History revealed that he repeatedly was affected by infections and had an extensive and severe clinical course, including nine revision surgeries. After a physical examination, imaging was performed, which further supported the diagnosis of joint infection. Considering the extensive number of attempts to salvage the joint, clinicians decided an above-knee amputation was necessary. This case highlights the fact that RA both increases the need for orthopedic arthroplasties and the risk of complications from these procedures, complicating clinical decision-making for physicians. Additionally, this patient had other underlying medical conditions and social habits that may have contributed to his severe clinical course, and we hope to explore these, discuss possible methods of modifying them, and assist clinicians in not only better treating similar patients but also emphasizing the importance of further developing standardized predictive algorithms and scoring tools.