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BACKGROUND: An unprecedented rise in the number of COVID-19-associated mucormycosis (CAM) cases has been reported in India. Myriad hypotheses are proposed for the outbreak. We recently reported uncontrolled diabetes and inappropriate steroid therapy as significant risk factors for the outbreak. However, Mucorales contamination of hospital environment was not studied. AIM: To perform a multi-centre study across India to determine possible Mucorales contamination of hospital environment during the outbreak. METHODS: Eleven hospitals from four zones of India representing high to low incidence for mucormycosis cases were included in the study. Samples from a variety of equipment used by the patients and ambient air were collected during May 19th, 2021 through August 25th, 2021. FINDINGS: None of the hospital equipment sampled was contaminated with Mucorales. However, Mucorales were isolated from 11.1% air-conditioning vents and 1.7% of patients' used masks. Other fungi were isolated from 18% of hospital equipment and surfaces, and 8.1% of used masks. Mucorales grew from 21.7% indoor and 53.8% outdoor air samples. Spore counts of Mucorales in air were significantly higher in the hospitals of North and South zones compared to West and East zones (P < 0.0001). Among Mucorales isolated from the environment, Rhizopus spp. were the most frequent genus. CONCLUSION: Contamination of air-conditioning vents and hospital air by Mucorales was found. Presence of Mucorales in these areas demands regular surveillance and improvement of hospital environment, as contamination may contribute to healthcare-associated mucormycosis outbreaks, especially among immunocompromised patients.
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COVID-19 , Mucorales , Mucormicose , Surtos de Doenças , Hospitais , Humanos , Índia/epidemiologia , Mucormicose/epidemiologiaRESUMO
We study the non-equilibrium (NE) fluctuation-dissipation (FD) relations in the context of quantum thermoelectric transport through a two-terminal nanodevice in the steady-state. The FD relations for the one- and two-particle correlation functions are derived for a model of the central region consisting of a single electron level. Explicit expressions for the FD relations of the Green's functions (one-particle correlations) are provided. The FD relations for the current-current and charge-charge (two-particle) correlations are calculated numerically. We use self-consistent NE Green's functions calculations to treat the system in the absence and in the presence of interaction (electron-phonon) in the central region. We show that, for this model, there is no single universal FD theorem for the NE steady state. There are different FD relations for each different class of problems. We find that the FD relations for the one-particle correlation function are strongly dependent on both the NE conditions and the interactions, while the FD relations of the current-current correlation function are much less dependent on the interaction. The latter property suggests interesting applications for single-molecule and other nanoscale transport experiments.
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We study the dynamical equation of the time-ordered Green's function at finite temperature. We show that the time-ordered Green's function obeys a conventional Dyson equation only at equilibrium and in the limit of zero temperature. In all other cases, i.e. finite temperature at equilibrium or non-equilibrium, the time-ordered Green's function obeys instead a modified Dyson equation. The derivation of this result is obtained from the general formalism of the non-equilibrium Green's functions on the Keldysh time-loop contour. At equilibrium, our result is fully consistent with the Matsubara temperature Green's function formalism and also justifies rigorously the correction terms introduced in an ad hoc way with Hedin and Lundqvist. Our results show that one should use the appropriate dynamical equation for the time-ordered Green's function when working beyond the equilibrium zero-temperature limit.
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We calculate the nonequilibrium charge transport properties of nanoscale junctions in the steady state and extend the concept of charge susceptibility to the nonequilibrium conditions. We show that the nonequilibrium charge susceptibility is related to the nonlinear dynamical conductance. In spectroscopic terms, both contain the same features versus applied bias when charge fluctuation occurs in the corresponding electronic resonances. However, we show that, while the conductance exhibits features at biases corresponding to inelastic scattering with no charge fluctuations, the nonequilibrium charge susceptibility does not. We suggest that measuring both the nonequilibrium conductance and charge susceptibility in the same experiment will permit us to differentiate between different scattering processes in quantum transport.
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We analyze how functionality could be obtained within single-molecule devices by using a combination of non-equilibrium Green's functions and ab initio calculations to study the inelastic transport properties of single-molecule junctions. First, we apply a full non-equilibrium Green's function technique to a model system with electron-vibration coupling. We show that the features in the inelastic electron tunneling spectra (IETS) of the molecular junctions are virtually independent of the nature of the molecule-lead contacts. Since the contacts are not easily reproducible from one device to another, this is a very useful property. The IETS signal is much more robust versus modifications at the contacts and hence can be used to build functional nanodevices. Second, we consider a realistic model of a organic conjugated molecule. We use ab initio calculations to study how the vibronic properties of the molecule can be controlled by an external electric field which acts as a gate voltage. The control, through the gate voltage, of the vibron frequencies and (more importantly) of the electron-vibron coupling enables the construction of functionality: nonlinear amplification and/or switching is obtained from the IETS signal within a single-molecule device.
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OBJECTIVE: Studies on malaria due to co-existent P. falciparum and P. vivax infections are negligible in India. Therefore, this study was undertaken to find out the clinical profile, prognostic factors, and outcome of mixed species malaria and to compare it with P. falciparum malaria. METHODS: This prospective, comparative study has been conducted in a tertiary health care institution with high prevalence of malaria. A cohort of 888 patients of malaria was enrolled in this study. The diagnosis of malaria was made either by Giemsa stained peripheral blood smear or RDT. Mixed species (MS) malaria was diagnosed when both P. vivax and P. falciparum were detected either from peripheral blood smear or RDT. Patients with P. falciparum malaria were grouped in to Pf group. The differences in clinical presentation, biochemical and haematological findings, occurrence of severe malaria, and outcome were recorded, compared, and analyzed. The severity of complication was assessed and Malaria Severity Score (MSS) was calculated. All the patients were treated according to WHO guidelines. RESULTS: Of them MS and Pf malaria constituted 118 (13.2%) and 770 (86.7%) patients respectively. Severe malaria was found in 17.8% (21 of 118) patients of MS and 57.1% (440 of 770) patients Pf malaria. Pf constituted 440 (95.5%) cases where as MS constituted 21 (4.5%) respectively. The number of severe malaria was significantly (p < 0.001) more in Pf than MS. Out of 21 cases of severe malaria in MS infection, 14 (66.6%) had single complication and 7 (33.3%) cases had multiple complication. However, in Pf mono infection there were 200 (45.5%) patients with single and 240 (54.5%) with multiple complication. There were 4 independent risk factors for a patient of developing complicated malaria. They were: presenting without fever, high parasite count, Pf mono infection, and fever to treatment interval. Multiple complications and high MSS are associated with increased death in Pf malaria. The outcome of patients of MS was good. CONCLUSION: In conclusion mixed species infection is not uncommon in the locality where both species coexists. Mixed species infection can complicate with severe malaria. However, its incidence and severity is less than severe falciparum malaria. In mixed infection, P.vivax malaria has a protective effect against the severity of falciparum malaria.
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Malária Falciparum/complicações , Malária Vivax/complicações , Adolescente , Adulto , Feminino , Febre/parasitologia , Humanos , Índia , Malária Falciparum/mortalidade , Malária Vivax/mortalidade , Masculino , Pessoa de Meia-Idade , Contagem de Ovos de Parasitas , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença , Adulto JovemRESUMO
We consider the interaction between electrons and molecular vibrations in the context of electronic transport in nanoscale devices. We present a method based on nonequilibrium Green's functions to calculate both equilibrium and nonequilibrium electronic properties of a single-molecule junction in the presence of electron-vibron interactions. We apply our method to a model system consisting of a single electronic level coupled to a single vibration mode in the molecule, which is in contact with two electron reservoirs. Higher-order diagrams beyond the usual self-consistent Born approximation (SCBA) are included in the calculations. In this paper we consider the effects of the double-exchange diagram and the diagram in which the vibron propagator is renormalized by one electron-hole bubble. We study in detail the effects of the first- and second-order diagrams on the spectral functions for a large set of parameters and for different transport regimes (resonant and off-resonant cases), both at equilibrium and in the presence of a finite applied bias. We also study the linear response (linear conductance) of the nanojunction for all the different regimes. We find that it is indeed necessary to go beyond the SCBA in order to obtain correct results for a wide range of parameters.
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A case of strongyloidiasis in common variable immunodeficiency is reported here. The patient was given several courses of albendazole without any response.
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AF18748 is disulphide-linked homodimeric peptide with 19 amino acids in each chain that antagonises the action of the eosinophil-specific cytokine, interleukin 5 (IL-5). We have generated a set of N-terminally truncated peptides derived from AF18748 and demonstrated that the first five amino acids of the peptide do not contribute to receptor binding activity. The shortened peptide blocked IL-5-dependent adhesion of eosinophils with an IC(50)of 350 pM, and had no effect on stimulation by IL-3, granulocyte-macrophage colony-stimulating factor (GM-CSF), tumour necrosis factor (TNF)-alpha or fMet-Leu-Phe. The peptides were rapidly broken down in mouse plasma through cleavage of a single chain of the dimer. However, this breakdown did not correlate with loss of biological activity, indicating that the asymmetric peptide fragment retains full receptor binding capacity. The activity of AF18748 disappeared rapidly from the blood following intravenous injection into mice. Coupling of polyethylene glycol to the N-terminus of AF18748 resulted in a moderate loss in biological potency (IC(50)30 nM), but the resulting conjugate persisted in the circulation for more than 8 h after injection. Despite its high potency at the human IL-5 receptor, AF18748 was unable to antagonise the activity of IL-5 on murine B13 cells, or on canine eosinophils, indicating that the peptide is highly specific for the human IL-5 receptor.
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Interleucina-5/antagonistas & inibidores , Peptídeos/farmacologia , Sequência de Aminoácidos , Aminoácidos/química , Animais , Linhagem Celular , Cães , Relação Dose-Resposta a Droga , Eosinófilos/metabolismo , Citometria de Fluxo , Granulócitos/metabolismo , Humanos , Concentração Inibidora 50 , Interleucina-3/farmacologia , Interleucina-5/farmacologia , Antígeno de Macrófago 1/metabolismo , Camundongos , Dados de Sequência Molecular , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Biossíntese Peptídica , Peptídeos/química , Polietilenoglicóis/farmacologia , Ligação Proteica , Sinais Direcionadores de Proteínas , Receptores de Interleucina/metabolismo , Receptores de Interleucina-5 , Espalhamento de Radiação , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Fatores de Tempo , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
WSL-1/TRAMP (DR3) is a member of the tumour necrosis factor (TNF) receptor superfamily which exhibits effects on NF-kappaB activation and apoptosis. TWEAK, a novel TNF-related molecule, has been proposed as the ligand for this receptor. Utilising both human and murine TWEAK ligand, it is shown that TWEAK and WSL-1/TRAMP do not interact in an in vitro binding assay and that TWEAK binds strongly to cells that do not express WSL-1/TRAMP on the cell surface. Biological activity of TWEAK is also observed in these cells. Finally, cells isolated from WSL-1/TRAMP knockout mice are shown to retain their ability to interact with TWEAK. These results suggest that WSL-1/TRAMP is not the major receptor for TWEAK
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Proteínas de Transporte/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Animais , Apoptose , Proteínas Reguladoras de Apoptose , Linhagem Celular , Citocina TWEAK , Humanos , Interleucina-8/farmacologia , Linfócitos/metabolismo , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Receptores do Fator de Necrose Tumoral/deficiência , Membro 25 de Receptores de Fatores de Necrose Tumoral , Fator de Necrose Tumoral alfa/metabolismo , Fatores de Necrose TumoralRESUMO
CD40 ligand (CD40L), a surface molecule which can be expressed by T cells, mast cells and basophils, has been shown to be involved in the control of B cell proliferation, immunoglobulin class switching as well as in the activation of monocytes and T cells. We demonstrate that CD40L can also be expressed constitutively by eosinophils from an hypereosinophilic patient or, upon activation, by the eosinophilic cell line EOL-3 and normal blood eosinophils. Eosinophils were able to induce, in conjunction with IL-4, CD40L-dependent B cell proliferation in vitro. These results suggest that CD40L could play a role in the inflammatory processes during which eosinophil infiltration and activation are observed.
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Eosinófilos/imunologia , Glicoproteínas de Membrana/biossíntese , Linfócitos B/imunologia , Northern Blotting , Ligante de CD40 , Linhagem Celular , Humanos , Síndrome Hipereosinofílica/imunologia , Ativação Linfocitária/imunologia , Reação em Cadeia da Polimerase , RNA Mensageiro/biossínteseAssuntos
Antifúngicos/farmacologia , Citometria de Fluxo/métodos , Pneumocystis/efeitos dos fármacos , Animais , Candida albicans/isolamento & purificação , Avaliação Pré-Clínica de Medicamentos/métodos , Estudos de Avaliação como Assunto , Técnicas In Vitro , Masculino , Testes de Sensibilidade Microbiana , Micologia/métodos , Infecções Oportunistas/microbiologia , Pneumocystis/isolamento & purificação , Pneumonia por Pneumocystis/microbiologia , Ratos , Ratos Sprague-DawleyRESUMO
Three city data sources (CDSs)--police reports, ambulance reports, and medica examiner (ME) logs--were evaluated for their usefulness in epidemiologic studies of trauma. The CDSs were employed to identify all cases of penetrating injury to the chest and/or abdomen severe enough to require care in a medical institution during 1979 and 1980 in Baltimore city. The percent of cases identified by source was: police, 66.8%; ambulance, 47.9%; ME, 16.6%; police plus ambulance, 89.4%; police plus ME, 82.9%; and ambulance plus ME, 50.1%. Hospital admissions to six study hospitals due to chest and/or abdomen penetrating injury were located and matched to the CDS reports: 89.2% of the hospitalized cases were reported in one or more CDS, and 34.7% of the cases identified by one or more CDS could not be located in the hospital records. Using hospital records as the standard, each source was determined to have the following completeness of case reporting: police, 66.2%; ambulance, 72.9%; and ME, 92.2%. The authors conclude that existing CDSs should be used with caution, and that the usefulness of data from multiple sources far outweighs that from any single source.