Publications by authors named "Alexandra Johansson"

The ability to detect and inactivate spore-forming bacteria is of significance within, for example, industrial, healthcare, and defense sectors. Not only are stringent protocols necessary for the inactivation of spores but robust procedures are also required to detect viable spores after an inactivation assay to evaluate the procedure's success. UV radiation is a standard procedure to inactivate spores.

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Background: Metastatic breast cancer (MBC) is a challenging disease, and despite new therapies, prognosis is still poor for a majority of patients. There is a clinical need for improved prognostication where immuno-oncology markers can provide important information. The aim of this study was to evaluate serum immuno-oncology markers in MBC patients and their respective relevance for prediction of survival.

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Here, we longitudinally assessed the ex vivo frequency and phenotype of SARS-CoV-2 membrane protein (aa145-164) epitope-specific CD4 T-cells of an anti-CD20-treated patient with prolonged viral positivity in direct comparison to an immunocompetent patient through an MHC class II DRB1*11:01 Tetramer analysis. We detected a high and stable SARS-CoV-2 membrane-specific CD4 T-cell response in both patients, with higher frequencies of virus-specific CD4 T-cells in the B-cell-depleted patient. However, we found an altered virus-specific CD4 T-cell memory phenotype in the B-cell-depleted patient that was skewed towards late differentiated memory T-cells, as well as reduced frequencies of SARS-CoV-2-specific CD4 T-cells with CD45RA CXCR5 PD-1 circulating T follicular helper cell (cT) phenotype.

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Local tumor-associated immune cells hold prognostic and predictive value in various forms of malignancy. The role of systemic, circulating leukocytes is, however, not well-characterized. In this prospective and explorative study, we aim to delineate the clinical relevance of a broad panel of circulating immune cells in 32 patients with newly diagnosed metastatic breast cancer (MBC) before the start of systemic treatment.

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Class II tetramer reagents for eleven common DR alleles and a DP allele prevalent in the world population were used to identify SARS-CoV-2 CD4+ T cell epitopes. A total of 112, 28 and 42 epitopes specific for Spike, Membrane and Nucleocapsid, respectively, with defined HLA-restriction were identified. Direct ex vivo staining of PBMC with tetramer reagents was used to define immunodominant and subdominant T cell epitopes and estimate the frequencies of these T cells in SARS-CoV-2 exposed and naïve individuals.

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Article Synopsis
  • - The study analyzed SARS-CoV-2-specific T cell responses in 34 individuals (10 with acute and 24 with resolved COVID-19) by testing 135 overlapping peptides from the virus's envelope, membrane, and nucleoprotein using methods like ELISpot and intracellular cytokine staining.
  • - A significant majority (97%) of participants showed CD4+ T cell responses to these peptides, with an average of 21.7 specific responses per patient and 10 identified peptides with over 36% response frequency.
  • - Notably, three peptides (Mem_P30, Mem_P36, and Ncl_P18) induced responses in over 55% of patients, leading to the development of a new tet
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We report the first measurement of sub-Doppler molecular response using a frequency comb by employing the comb as a probe in optical-optical double-resonance spectroscopy. We use a 3.3  μm continuous wave pump and a 1.

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We correct the values of the group delay dispersion of the cavity mirrors and N, as well as the concentration of CO, obtained from the measurement of the center frequencies of cavity modes using a comb-based Fourier transform spectrometer. The corrected values of group delay dispersion are a factor of 3 higher, which implies that the precision and accuracy of the dispersion measurements is 0.3 fs and 3 fs, respectively.

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We present broadband cavity-enhanced complex refractive index spectroscopy (CE-CRIS), a technique for calibration-free determination of the complex refractive index of entire molecular bands via direct measurement of transmission modes of a Fabry-Perot cavity filled with the sample. The measurement of the cavity transmission spectrum is done using an optical frequency comb and a mechanical Fourier transform spectrometer with sub-nominal resolution. Molecular absorption and dispersion spectra (corresponding to the imaginary and real parts of the refractive index) are obtained from the cavity mode broadening and shift retrieved from fits of Lorentzian profiles to the individual cavity modes.

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Optical cavities provide high sensitivity to dispersion since their resonance frequencies depend on the index of refraction. We present a direct, broadband, and accurate measurement of the modes of a high finesse cavity using an optical frequency comb and a mechanical Fourier transform spectrometer with a kHz-level resolution. We characterize 16000 longitudinal cavity modes spanning 16 THz of bandwidth in terms of center frequency, linewidth, and amplitude.

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We present a versatile mid-infrared frequency comb spectroscopy system based on a doubly resonant optical parametric oscillator tunable in the 3-5.4 μm range and two detection methods: a Fourier transform spectrometer (FTS) and a continuous-filtering Vernier spectrometer (CF-VS). Using the FTS with a multipass cell, we measure high precision broadband absorption spectra of CH at 3.

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The term goal directed conventionally refers to either of 2 separate process types-motor processes organizing action oriented toward physical targets and decision-making processes that select these targets by integrating desire for and knowledge of action outcomes. Even newborns are goal directed in the first sense, but the status of infants as decision makers (the focus here) is unknown. In this study, 24-month-olds learned to retrieve an object from a box by pressing a button, and then the object's value was increased.

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