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1.
Nature ; 583(7818): E32, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32665716

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

2.
Nature ; 582(7812): 375-378, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32555487

RESUMO

Imaging of biomolecules guides our understanding of their diverse structures and functions1,2. Real-space imaging at sub-nanometre resolution using cryo-electron microscopy has provided key insights into proteins and their assemblies3,4. Direct molecular imaging of glycans-the predominant biopolymers on Earth, with a plethora of structural and biological functions5-has not been possible so far6. The inherent glycan complexity and backbone flexibility require single-molecule approaches for real-space imaging. At present, glycan characterization often relies on a combination of mass spectrometry and nuclear magnetic resonance imaging to provide insights into size, sequence, branching and connectivity, and therefore requires structure reconstruction from indirect information7-9. Here we show direct imaging of single glycan molecules that are isolated by mass-selective, soft-landing electrospray ion beam deposition and imaged by low-temperature scanning tunnelling microscopy10. The sub-nanometre resolution of the technique enables the visualization of glycan connectivity and discrimination between regioisomers. Direct glycan imaging is an important step towards a better understanding of the structure of carbohydrates.


Assuntos
Polissacarídeos/análise , Polissacarídeos/química , Imagem Individual de Molécula , Manosídeos/análise , Manosídeos/química , Microscopia de Tunelamento
3.
Clin Radiol ; 79(3): e475-e481, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38145924

RESUMO

AIM: To examine the volumes of the medial and lateral femoral condyles and the trochlear groove, and to determine their relationship with trochlear dysplasia. MATERIALS AND METHODS: Computed tomography images of the knees of 21 patients with trochlear dysplasia and 18 healthy individuals were analysed retrospectively. According to the modified Dejour classification, the degree of trochlear dysplasia was recorded, such as type A trochlea being low-grade dysplasia and types B, C, and D trochlea being high-grade dysplasia. Volume of the trochlear groove and medial and lateral femoral condyles were calculated using the three-dimensional (3D) volume-rendering method. RESULTS: The volumes of lateral condyle, medial condyle, and trochlear groove were statistically significantly lower in patients with trochlear dysplasia when compared to healthy participants. When compared according to Dejour types, all parameters were statistically significantly lower in both high- and low-grade dysplasia patients (p<0.05). The correlation between femoral condyle volumes and trochlear groove volume was low in the control group, but there was a moderate positive correlation in the patient group (r=0.50-0.75, p<0.05). CONCLUSION: In trochlear dysplasia, the volume of the trochlear groove decreases and hypoplasia may occur in both lateral femoral and medial femoral condyles. Therefore, hypoplasia of only one condyle should not be interpreted as trochlear dysplasia. A holistic approach to patients is required.


Assuntos
Instabilidade Articular , Humanos , Projetos Piloto , Estudos Retrospectivos , Articulação do Joelho/diagnóstico por imagem , Fêmur/diagnóstico por imagem
4.
Niger J Clin Pract ; 26(2): 229-233, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36876613

RESUMO

Background: It is suggested that stress related to infertility causes marriage conflicts and decreases in the frequency of sexual intercourse. Aim: This study aimed to explore the experiences of the sexuality of infertile women. Patients and Methods: A phenomenological design was used in this study. We conducted face-to-face, semistructured, in-depth interviews with 11 infertile women. The interviews were audio-recorded, and a thematic approach was used to assess the data. Results: The average age of the women was 33.05 ± 3.40 years, and their age of first sexual intercourse was 23.0 ± 2.8 years and all of them are legally married. The durations of experiencing the problem of infertility were as follows; 3-5 years in 33%, 6-10 years in 27%, and 11 years and above in 38%. According to interpretative phenomenological analysis, two main themes emerge. Two main themes were determined: Perception of Sexuality and Sexual Problems. The results show that infertile women have a higher risk for sexual dysfunction than fertile women. Conclusion: These findings suggest that the diagnosis of infertility is an important factor in assessing the differences in the sexual satisfaction of women. In infertility counseling, health professionals must explain the gender differences. Also, infertile couples must encourage to share each other's feelings and this may help couples to cope with the communication problems they may experience.


Assuntos
Infertilidade Feminina , Feminino , Humanos , Adulto , Adulto Jovem , Comportamento Sexual , Sexualidade , Fertilidade , Pesquisa Qualitativa
5.
Niger J Clin Pract ; 26(7): 949-956, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37635579

RESUMO

Background: In the postpartum period, changes including pain during intercourse, lack of sexual desire, vaginal dryness, and failure to reach orgasm can affect a woman's sexual response cycle. Aim: This research aimed to determine the effect of midwifery training on postpartum sexual dysfunction among primiparous women. Subjects and Methods: This research using a single-blind randomized controlled experimental and follow-up design. The sample consisted of 70 women, divided equally into training and control groups. Research data were collected using an information form, the Female Sexual Function Index and the Arizona Sexual Experience Scale. In the first phase of our study, 306 primiparous women were interviewed. Results: The mean Female Sexual Function Index score of the women was 25.18 ± 5.47 and 40.2% reported sexual dysfunction. When comparing the training and control groups before training, the total score average of the ASEX was 10.48 ± 2.13 in the training group and 11.06 ± 3.86 in the control group. The average score in the post-training was higher in the group given education (22.45 ± 2.17) than in the control group (17.08 ± 3.92) and this difference was significant (p = 0.000). It was determined that 42% of the change in the third follow-up scores of pregnant women in the training group could be explained by the education session they received. Conclusion: Our data showed a positive change in the sexual dysfunction scores of women, suggesting the education program was successful.


Assuntos
Coito , Comportamento Sexual , Gravidez , Feminino , Humanos , Método Simples-Cego , Escolaridade , Período Pós-Parto
6.
Clin Radiol ; 77(4): e329-e336, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35144768

RESUMO

AIM: To investigate a possible relationship between both the volume and morphology of the patella and the volume of the trochlea in trochlear dysplasia (TD). MATERIALS AND METHODS: Eighteen patients with TD and 18 controls were evaluated retrospectively in two groups using computed tomography (CT). Patellar morphology was evaluated with the standard measurement methods described in the literature. Additionally trochlear sulcus volume (TV) and patellar volume (PV) were measured quantitatively using the three-dimensional volume-rendering method. The relationship between patella dimensions and volume and trochlea volume was evaluated. RESULTS: The length of the medial patellar facet (lMP), patellar width (PW), TV and PV were significantly lower in the patient group. When compared according to Dejour types, PW was statistically significantly lower than the control group in those with high-grade and those with low-grade dysplasia. A positive correlation was found between the TV and PV in both groups (patient group: r=0.583 p=0.011; control group: r=0.485 p=0.042). CONCLUSIONS: PV and the TV are related. Therefore, PV can be used as a determining parameter in the evaluation of TD. This technique can also be used for prosthesis construction and more accurate surgical planning.


Assuntos
Patela , Implantação de Prótese , Humanos , Hiperplasia , Patela/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
7.
Lett Appl Microbiol ; 75(2): 450-459, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35620862

RESUMO

In this study, an endophytic Bacillus sp. strain (K7) was isolated from the medicinally important ornamental plant, Jasminum officinale. Biochemical analyses were conducted to evaluate the nature of the extracted product, which displayed strong anticandidal activity against Candida albicans (CA) SC5314, as evident from the results obtained in agar-cup diffusion tests, phase-contrast microscopy, scanning electron microscopy and minimum inhibitory concentration assays. After confirming the presence of the gene clusters encoding the lipopeptides iturins and fengycin in the genome of K7, their corresponding molecular ions were identified using MALDI-TOF-MS. 3D structures of the lipopeptides were downloaded from specific databases and molecular docking was performed against a vital CA enzyme, exo-1,3-beta-glucanase, involved in cell wall remodelling, adhesion to polymer materials and biofilm formation. The docking score of iturins was found to be -8·6 and -8·2 kcal mol-1 and for fengycin it was -9·4 kcal mol-1 , indicating a strong affinity of these cyclic lipopeptides towards exo-1,3-beta-glucanase. The combined in vitro and in silico anticandidal studies suggested that these secreted lipopeptides from Bacillus sp. may be used as potential therapeutics against opportunistic and complicated infections of CA.


Assuntos
Bacillus , Bacillus/metabolismo , Candida albicans/metabolismo , Glucana 1,3-beta-Glucosidase/metabolismo , Lipopeptídeos/farmacologia , Simulação de Acoplamento Molecular , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia
8.
Faraday Discuss ; 228(0): 242-265, 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-33687396

RESUMO

The acetylene-vinylidene system serves as a benchmark for investigations of ultrafast dynamical processes where the coupling of the electronic and nuclear degrees of freedom provides a fertile playground to explore the femto- and sub-femto-second physics with coherent extreme-ultraviolet (EUV) photon sources both on the table-top as well as free-electron lasers. We focus on detailed investigations of this molecular system in the photon energy range 19-40 eV where EUV pulses can probe the dynamics effectively. We employ photoelectron-photoion coincidence (PEPICO) spectroscopy to uncover hitherto unrevealed aspects of this system. In this work, the role of excited states of the C2H2+ cation, the primary photoion, is specifically addressed. From photoelectron energy spectra and angular distributions, the nature of the dissociation and isomerization channels is discerned. Exploiting the 4π-collection geometry of the velocity map imaging spectrometer, we not only probe pathways where the efficiency of photoionization is inherently high but also perform PEPICO spectroscopy on relatively weak channels.

9.
J Chem Phys ; 154(9): 094507, 2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33685144

RESUMO

The onset of shear thinning and the transition from Newtonian to non-Newtonian behavior in the viscous flow of select chalcogenide and oxide network glass-forming liquids in the deeply supercooled regime and its temperature dependence are studied using parallel plate rheometry. In all cases, the onset occurs at a shear rate γ̇c that is several orders of magnitude lower than the shear relaxation rate τ0 -1 and the former increases with increasing temperature. These results are in good qualitative agreement with the predictions of the existing models of shear relaxation and shear thinning based on the nonlinear Langevin equation theory, random first order transition theory, and the free volume model. However, in contrast to the theoretical predictions, the reduced shear rate W0 (=τ0γ̇c) at the onset is found to range between 10-3 and 10-5 and decrease with increasing temperature. This temperature dependence becomes stronger with increasing fragility of the liquid. These results likely indicate that the shear thinning mechanism in network liquids could be fundamentally different from those in molecular, metallic, or polymeric glass-formers.

10.
Lett Appl Microbiol ; 72(4): 445-457, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33278831

RESUMO

Textile effluent is generally complicated to manage because of its extremely noxious and recalcitrant coloured compositions. Mycoremediation is an extensively used strategy for the competent degradation of hazardous pollutants present in textile effluent. Fungus could be immobilized in synthetic or natural matrices. The current study shows the decolourization of the textile effluent by 85·5 and 98·5% within 6 h using suspended and immobilized fungus, Geotrichum candidum with optimized parameters like inoculum size (5%), pH (4·5), and temperature (30°C). To maintain a high biomass of fungal population and enhance the retention of fungal strain in the contaminated sites, the fungi need to be immobilized. Hence, the fungus was immobilized naturally onto the selected inert support that is, coconut fibres by the means of adsorption, where they grew as active films on the fibres after being grown in the culture broth. The optimized process parameters of inoculum size, fibre quantity and agitation speed for immobilized G. candidum were 5%, 2·2 g l-1 of effluent and 100 rev min-1 respectively. High level of laccase (22 and 25 U l-1 in suspended and immobilized fungal cells treatment respectively) was observed during the process of decolourization and it was found that decolourization was directly proportional to the laccase activity. The UV-vis, FTIR, 1 H NMR and GC-MS analyses of treated textile industrial wastewater revealed the degradation of toxic pollutants in the textile effluent and formation of lower molecular weight intermediates. The study revealed a higher efficacy of immobilized G. candidum in comparison to suspended fungal culture, employing ligninolytic enzyme laccase, which catalyzes the degradation/transformation of aromatic dyes in the textile effluent thus decolourizing it.


Assuntos
Biodegradação Ambiental , Corantes/metabolismo , Geotrichum/metabolismo , Águas Residuárias/química , Purificação da Água/métodos , Resíduos Industriais/análise , Lacase/metabolismo , Têxteis
11.
J Postgrad Med ; 67(1): 43-45, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33533751

RESUMO

Immune-checkpoint inhibitor mediated hepatobiliary injury is an emerging concern in cancer treatment. Most of these adverse reactions are attributed to nivolumab and are characterized by panlobular hepatitis. Large duct cholangiopathy related to these drugs is extremely rare. We present a case of adenocarcinoma of lung treated with pembrolizumab who developed biochemical and imaging features consistent with cholangiopathy characterized by common bile duct dilatation, wall enhancement, and gallbladder wall edema. On follow-up in the fourth month, the imaging features persisted despite the normalization of liver enzymes. To the best of our knowledge, this is the first description of diagnosis and follow-up imaging of pembrolizumab-related cholangiopathy in imaging literature.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos Imunológicos/efeitos adversos , Doença Hepática Crônica Induzida por Substâncias e Drogas , Doenças do Sistema Digestório/patologia , Adenocarcinoma de Pulmão/tratamento farmacológico , Colangiografia , Ducto Colédoco , Doenças do Sistema Digestório/induzido quimicamente , Humanos , Neoplasias Pulmonares/tratamento farmacológico
12.
J Appl Microbiol ; 129(6): 1633-1643, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32491245

RESUMO

AIM: The aim of the study is to investigate the efficiency of Geotrichum candidum in the decolourization and mineralization of synthetic azo dyes. METHODS AND RESULTS: It includes screening of enzymes from G. candidum and its optimization, followed by decolourization and mineralization studies. Decolourization was observed to be maximum in methyl orange (94·6%) followed by Congo red (85%), trypan blue (70·4%) and Eriochrome Black T (55·6%) in 48 h, suggesting the plausible degradation of the azo dyes by G. candidum. The enzyme activity study showed that DyP-type peroxidase has highest activity of 900 mU ml-1 compared to that of laccase (405 mU ml-1 ) and lignin peroxidase (LiP) (324 mU ml-1 ) at optimized pH (6) and temperature (35°C). Moreover, the rate of decolourization was found to be directly proportional to the production of laccase and LiP, unlike DyP-type peroxidase. Furthermore, mineralization study demonstrated reduction in aromatic amines, showing 20% mineralization of methyl orange. CONCLUSION: Geotrichum candidum with its enzyme system is able to efficiently decolourize and mineralize the experimental azo dyes. SIGNIFICANCE AND IMPACT OF THE STUDY: The efficient decolourization and mineralization of azo dyes makes G. candidum a promising alternative in the treatment of textile effluent contaminated with azo dyes.


Assuntos
Compostos Azo/metabolismo , Corantes/metabolismo , Proteínas Fúngicas/metabolismo , Geotrichum/enzimologia , Descoloração da Água/métodos , Biodegradação Ambiental , Geotrichum/metabolismo , Lacase/metabolismo , Peroxidase/metabolismo , Peroxidases/metabolismo , Têxteis
13.
J Chem Phys ; 153(13): 134504, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33032422

RESUMO

The viscoelastic behavior of supercooled glass-forming liquids along the binary join As4S3-GeS2 with As4S3 contents varying from 81.25 to 9 mol. % and correspondingly with structures varying from predominantly molecular to a three-dimensional tetrahedral network is studied by small-amplitude oscillatory shear parallel plate rheometry. The storage shear modulus G' shows a scaling behavior of G'(ω) ∼ ωn in the terminal (low-frequency) regime, where n varies between 1 and 2 and shows an increasingly anomalous departure from the expected value of 2 (Maxwell scaling) with increasing molecule content. A concomitant departure from the Maxwell scaling is also observed for the loss modulus G″ at frequencies above the G'-G″ crossover. On the other hand, the variation in the phase angle δ with the complex modulus indicates that the molecular liquid does not display a purely viscous response even at the lowest frequencies. These results, combined with an analysis of the relaxation spectra of these liquids, suggest that the anomalous behavior of molecular liquids may be linked to their rather broad relaxation spectrum and the presence of slow relaxation processes associated with molecular clusters. Additionally, these liquids are also characterized by a wide high-frequency plateau in the relaxation spectral density that can be linked to the rotational dynamics of the constituent molecules. Such fundamental differences between the rheological behavior of molecular and network liquids may explain the significantly higher fragility of the former.

14.
Am J Emerg Med ; 38(4): 853.e5-853.e6, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31839516

RESUMO

INTRODUCTION: To the majority of health care professionals, burns present as a challenging and potentially distracting diagnosis. Because of their perceived complexity, they often eclipse other medical problems which can often be life threatening. Pressure related injuries, in rare instances can mimic and be mistaken for full thickness burns. Long lies may cause pressure necrosis of decubitus areas and compartment syndrome of vulnerable areas. Compartment syndrome, is a surgical emergency requiring prompt diagnosis and intervention. It may be missed in the context of a long lie after a collapse and maybe detrimental to patients' prognosis. METHODS: We reviewed cases referred to our Burns unit in the last four months to find cases of pressure related injuries referred as burn wounds. Furthermore, we also performed a literature search to find any similar cases to ours. RESULTS: Two cases, with acute pressure related injuries from long lies had been mistaken for burn wounds, were referred to our unit in the last four months. In one case a missed compartment syndrome resulted in a below elbow amputation. CONCLUSION: Pattern analysis and recognition are very important diagnostic tools in medicine. Detailed history taking and examination cannot be emphasised enough. Training both emergency departments and plastic surgeons in recognising long lie related injuries will decrease possible associated dangers such as missing a compartment syndrome.


Assuntos
Queimaduras/diagnóstico , Erros de Diagnóstico , Úlcera por Pressão/diagnóstico , Acidentes por Quedas , Idoso , Queimaduras/patologia , Síndromes Compartimentais/diagnóstico , Síndromes Compartimentais/etiologia , Síndromes Compartimentais/patologia , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pressão/efeitos adversos , Úlcera por Pressão/patologia
15.
Med J Armed Forces India ; 76(2): 136-141, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32341622

RESUMO

The world is currently face to face with a pandemic which is spreading rapidly across the globe caused by SARS-CoV-2, a strain of Coronaviruses (CoVs) belonging to subgenus Sarbecovirus of genus Betacoronavirus. World Health Organisation (WHO) on 11 Feb 20 named this disease caused by SARS-CoV-2 as Covid-19. This pandemic is spreading rapidly and more than 20,00,000 cases have occurred globally. The human Coronaviruses discovered in 1960s were considered potentially harmless endemic viruses with seasonal distribution before late 2002. The CoVs are found in a large number of domestic and wild animals and birds. The first pandemic caused by Coronavirus caused by SARS-CoV was recognized in the late 2002 in Guangdong Province and resulted in widespread morbidity and mortality. This was followed by MERS-CoV which began in 2012 in the Arabian peninsula with multiple outbreaks related to it in various parts of the globe. Various studies have suggested how these viruses made their entry from their natural reservoir bats via intermediate host like civets and camels in case of SARS-CoV and MERS-CoV respectively. The intermediate host of the SARS-CoV-2 still needs to be established. The SARS-CoV-2 has 96.2% similarity to the bat Severe Acute Respiratory Syndrome related-Coronavirus (SARSr-CoV RaTG13). SARS-CoV-2 has been found to be more distant in relation to SARS-CoV (79%) and MERS-CoV (50%). At the whole genome sequence level pangolin CoV and SARSr-CoV RaTG13 show 91.02% and 96.2% similarity with SARS-CoV-2 but the S1 subunit of spike protein of pangolin CoV is more closely related to SARS-CoV-2 than SARSr-CoV RaTG13. The genetic analysis of the currently circulating strains of the pandemic have shown 99.98-100% similarity in their genomes implying a recent shift to humans. The animal source of SARS-CoV-2 needs to be identified to implement control measures in the present pandemic. Also, how the virus moves interspecies will help predict and prevent future pandemics.

16.
Osteoporos Int ; 29(2): 329-337, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29110061

RESUMO

The goal of this multinational, prospective, observational study was to examine the relationship between gastrointestinal (GI) events and self-reported levels of medication adherence and persistence in postmenopausal women. A total of 73.9% of patients remained on their osteoporosis (OP) therapy at month 12, although the presence of a GI event at baseline, month 3, and month 6 significantly reduced month 12 persistence among new users. The odds of a month-12 ADEOS score ≥ 20 were significantly lower among patients who experienced a GI event between baseline and month 6. The occurrence of GI events was observed to be associated with a lower likelihood of patient adherence and persistence to OP medication. INTRODUCTION: This study examines the relationship between gastrointestinal (GI) events and self-reported adherence and persistence with initial osteoporosis (OP) therapy over the course of the first 12 months of treatment. METHODS: The Medication Use Patterns, Treatment Satisfaction, and Inadequate Control of Osteoporosis Study was a multinational, prospective, observational study examining the impact of GI events on OP management in postmenopausal women. Information regarding GI events was collected at the time of enrollment and at months 3, 6, and 12 of follow-up. Patients reported GI events and medication persistence and completed the 12-item Adherence Evaluation of Osteoporosis treatment (ADEOS) questionnaire. Multivariate logistic and general linear models examined the association between GI events at various time points and persistence and adherence at month 12. RESULTS: The study enrolled 2943 women; 22.8% were classified as new users of OP therapy and the remainder were considered experienced users. Across all patients, 68.1% reported GI events at baseline; by month 12, over 80% of subjects who completed follow-up reported at least one GI problem. The majority of patients (86.7%) were treated only with bisphosphonates at baseline. At month 12, 73.9% of patients remained on therapy; logistic regression revealed that those with GI problems by month 6 were significantly less likely to persist with treatment, after adjusting for other factors. The odds of a month 12 ADEOS score ≥ 20 (considered predictive of adherence) were significantly lower among patients who experienced a GI event between baseline and month 6. CONCLUSIONS: The occurrence of GI events was associated with a lower likelihood of patient adherence to and persistence with OP medication.


Assuntos
Conservadores da Densidade Óssea/efeitos adversos , Gastroenteropatias/induzido quimicamente , Adesão à Medicação/estatística & dados numéricos , Osteoporose Pós-Menopausa/tratamento farmacológico , Acidentes por Quedas/estatística & dados numéricos , Idoso , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/uso terapêutico , Canadá/epidemiologia , Difosfonatos/administração & dosagem , Difosfonatos/efeitos adversos , Difosfonatos/uso terapêutico , Esquema de Medicação , Europa (Continente)/epidemiologia , Feminino , Seguimentos , Gastroenteropatias/epidemiologia , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/epidemiologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/prevenção & controle , Estudos Prospectivos , Autorrelato
17.
J Chem Phys ; 148(11): 111101, 2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29566499

RESUMO

The rheological behavior of supercooled Se, As10Se90, and As20Se80 liquids is studied in the linear regime as a function of frequency, extending over nearly 11 orders of magnitude, using oscillatory parallel plate rheometry. While the viscoelastic response of the As20Se80 liquid is characterized by a single relaxation time scale, the Se and the As10Se90 liquids display two distinct relaxation processes, both of which are coupled to viscosity, although their time scales differ by nearly 3-5 orders of magnitude. The ultra-slow relaxation process appears to be related to the dynamics of -Se-Se-Se- chain segments in the structure of these liquids, with characteristic time scale and shear modulus that are dependent on the average chain length. The fast mode, on the other hand, is associated with the glassy modulus and is tentatively assigned to a Johari-Goldstein ß-process. These results, when taken together, are consistent with the presence of a hierarchical free energy landscape that characterizes the dynamics of the fragile Se and As10Se90 liquids.

18.
J Chem Phys ; 148(20): 204507, 2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-29865839

RESUMO

A comprehensive analysis of the ionic dynamics in a wide variety of crystalline and glassy ionic conductors, obtained in recent studies using a combination of electrochemical impedance and nuclear magnetic resonance spectroscopic techniques, is presented. These results demonstrate that the crossover frequency, between the frequency-independent dc conductivity and the frequency-dependent ac conductivity, corresponds to the time scale of "successful" diffusive hops of the mobile ions between the trapping sites in the structure. These inter-site hops are typically compound in nature and consist of several elementary hops in the intervening region between the neighboring trapping sites.

19.
BMC Nephrol ; 19(1): 89, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29665795

RESUMO

BACKGROUND: Removal of uraemic toxins is inadequate using current dialysis strategies. A new class of dialysis membranes have been developed that allow clearance of larger middle molecules. The REMOVAL-HD study (a tRial Evaluating Mid cut-Off Value membrane clearance of Albumin and Light chains in HaemoDialysis patients) will address safety, efficacy and the impact on patient-centred outcomes with the use of a mid cut-off (MCO) dialyser in a chronic haemodialysis (HD) population. METHODS: REMOVAL-HD is an open label, prospective, non-randomised, single-arm, multi-centre device study in 85 chronic HD participants. All visits will be conducted during regular HD sessions and participants will undergo a 1 month wash-in period using a standardised high flux dialyser, 6 months of intervention with a MCO dialyser and 1 month of wash-out using a high flux dialyser. The primary endpoint is change in pre-dialysis concentrations of serum albumin, with secondary endpoints including the efficacy of clearance of free light chains and ß-2 microglobulin, and patient-centred outcomes including quality of life, symptom burden, functional status, nutritional status, hospitalisation and death. DISCUSSION: MCO dialysers are a novel form of HD membrane. The REMOVAL-HD study is a pivotal study designed to monitor the immediate and medium-term effects following exposure to this dialyser. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry Number (ANZCTRN) 12616000804482 . Date of registration - 21/06/2016.


Assuntos
Cadeias lambda de Imunoglobulina/sangue , Membranas Artificiais , Diálise Renal/instrumentação , Insuficiência Renal Crônica/terapia , Projetos de Pesquisa , Albumina Sérica/metabolismo , Adulto , Efeitos Psicossociais da Doença , Hospitalização , Humanos , Estado Nutricional , Avaliação de Resultados da Assistência ao Paciente , Estudos Prospectivos , Qualidade de Vida , Diálise Renal/efeitos adversos , Diálise Renal/métodos , Insuficiência Renal Crônica/sangue , Análise de Sobrevida , Microglobulina beta-2/sangue
20.
Niger J Clin Pract ; 21(7): 827-831, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29984711

RESUMO

BACKGROUND AND AIM: Development of phlebitis is a painful and common complication in the application of peripheral intravenous catheter (PIC). This is a prospective observational study performed to identify development rate of phlebitis in application of PIC and the factors that affect the development of phlebitis. MATERIALS AND METHODS: The study universe comprises of catheters applied on inpatients in the internal diseases clinic of a state hospital, and the sample comprises of catheters eligible to be included in the study. Five hundred and thirty-two PICs applied on a total of 317 patients were reviewed. The patient identification form, information form for peripheral venous catheter and treatment, and visual infusion phlebitis (VIP) assessment scale were used to collect data. RESULTS: 31.8% had phlebitis and a large number of them (79.2%) were Level I phlebitis. There was a significant relationship between having a chronic disease, duration of catheterization and type of fluid used and the development rate of phlebitis. CONCLUSION: The phlebitis in individuals receiving intravenous (IV) treatment was higher than the rate defined by both the centers for disease control and prevention and IV nurses society. It may be recommended to assess phlebitis by VIP assessment scale and to take preventive measures specifically for development of phlebitis.


Assuntos
Cateterismo Periférico/efeitos adversos , Infusões Intravenosas/efeitos adversos , Flebite/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cateterismo Periférico/instrumentação , Catéteres , Contaminação de Equipamentos , Feminino , Humanos , Infecções/etiologia , Infusões Intravenosas/instrumentação , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Sepse/etiologia , Estados Unidos
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