Long-term follow-up of production of IgM and IgG antibodies against SARS-CoV-2 among patients with COVID-19

The patients diagnosed with coronavirus disease 2019 （COVID-19） produce IgM and IgG antibodies against severe acute respiratory syndrome coronavirus 2 （SARS-CoV-2）. However, the frequency and duration of antibody production still need to be fully understood. In the present study, we investigated the duration of antibody production after SARS-CoV-2 infection. The patients diagnosed with COVID-19 were monitored over twelve months for the production of SARS-CoV-2 IgM and IgG antibodies, and the characteristics of these patients were examined. Forty-five patients diagnosed with COVID-19 were enrolled, and thirty-four patients were followed up until they tested negative for SARS-CoV-2 IgM and IgG antibodies or up to twelve months after the date of a negative SARS-CoV-2 polymerase chain reaction （PCR） result. The positivity rates of SARS-CoV-2 IgM and IgG antibodies were 27.3％ and 68.2％ when SARS-CoV-2 PCR was negative, 20.6％ and 70.6％ after one month, 8.8％ and 52.9％ after three months, and 0.0％ and 14.7％ after six months, respectively. Moreover, we compared patients with milder conditions who did not require oxygen administration with those with severe conditions which required oxygen administration. The positivity rate of SARS-CoV-2 IgG antibodies was significantly higher in patients with severe conditions than in those with milder conditions on the date of a negative SARS-CoV-2 PCR result and after one month and three months, but not after six months. Patients with more severe COVID-19 produced more SARS-CoV-2 IgG antibodies. Moreover, it is suggested that the duration of IgG antibody production is independent of COVID-19 severity

Direct Observation of Cooperative Protein Structural Dynamics of Homodimeric Hemoglobin from 100 ps to 10 ms with Pump–Probe X-ray Solution Scattering

Proteins serve as molecular machines in performing their biological functions, but the detailed structural transitions are difficult to observe in their native aqueous environments in real time. For example, despite extensive studies, the solution-phase structures of the intermediates along the allosteric pathways for the transitions between the relaxed (R) and tense (T) forms have been elusive. In this work, we employed picosecond X-ray solution scattering and novel structural analysis to track the details of the structural dynamics of wild-type homodimeric hemoglobin (HbI) from the clam Scapharca inaequivalvis and its F97Y mutant over a wide time range from 100 ps to 56.2 ms. From kinetic analysis of the measured time-resolved X-ray solution scattering data, we identified three structurally distinct intermediates (I-1, I-2, and I-3) and their kinetic pathways common for both the wild type and the mutant. The data revealed that the singly liganded and unliganded forms of each intermediate share the same structure, providing direct evidence that the ligand photolysis of only a single subunit induces the same structural change as the complete photolysis of both subunits does. In addition, by applying novel structural analysis to the scattering data, we elucidated the detailed structural changes in the protein, including changes in the heme heme distance, the quaternary rotation angle of subunits, and interfacial water gain/loss. The earliest, R-like I-1 intermediate is generated within 100 ps and transforms to the R-like I-2 intermediate with a time constant of 3.2 +/- 0.2 ns. Subsequently, the late, T-like I-3 intermediate is formed via subunit rotation, a decrease in the heme-heme distance, and substantial gain of interfacial water and exhibits ligation-dependent formation kinetics with time constants of 730 +/- 120 ns for the fully photolyzed form and 5.6 +/- 0.8 mu s for the partially photolyzed form. For the mutant, the overall kinetics are accelerated, and the formation of the T-like I-3 intermediate involves interfacial water loss (instead of water entry) and lacks the contraction of the heme-heme distance, thus underscoring the dramatic effect of the F97Y mutation. The ability to keep track of the detailed movements of the protein in aqueous solution in real time provides new insights into the protein structural dynamics.1149sciescopu

Deformation and improvement for the IR transmission of single-crystal silicon by direct current heating

We confirmed that the deformation occurred at about 800 °C when CZ-Si was pressure and heat treated by a pulse-heating method, spark plasma sintering (SPS), while at the same time, the absorption peak of silicon single crystal produced using the Czochralski process (CZ-Si), which was a major issue for infrared transparent material in the vicinity of 9 μm, was also confirmed to have been reduced within a short time. The absorption coefficient in the vicinity of 9 μm, which was derived from the interstitial oxygen, decreased the most at 800 °C, and the absorption derived from the stretching mode of Si–O observed inthe vicinity of 9.7 μm reached its maximum at 800 °C. This is considered to have been due to the migration of interstitial oxygen via clusters to change the material into amorphous SiO2. It was confirmed that the impact of the applied pressure direction was relative to crystal orientation on the peak of 9 μm. It was also found that the deformation was the maximum from the (110) plane, that the change in absorption coefficients before and after deformation was the largest, and that the relationship turned out to be (110)> (100)> (111). The dislocation lines in the sample after the deformation of the (100) plane were observed using EBSD, and the polarization dependencies of transmittance in the infrared region were measured for the planes parallel and perpendicular to the applied pressure

The Significance of the Prognostic Nutritional Index in Patients with Completely Resected Non-Small Cell Lung Cancer.

Immunological parameters and nutritional status influence the outcome of patients with malignant tumors. A prognostic nutritional index, calculated using serum albumin levels and peripheral lymphocyte count, has been used to assess prognosis for various cancers. This study aimed to investigate whether this prognostic nutritional index affects overall survival and the incidence of postoperative complications in patients with completely resected non-small cell lung cancer.We retrospectively reviewed the medical records of 409 patients with non-small cell lung cancer who underwent complete resection between 2005 and 2007 at the Aichi Cancer Center.The 5-year survival rates of patients with high (≥50) and low (<50) prognostic nutritional indices were 84.4% and 70.7%, respectively (p = 0.0011). Univariate analysis showed that gender, histology, pathological stage, smoking history, serum carcinoembryonic antigen levels, and prognostic nutritional index were significant prognostic factors. Multivariate analysis identified pathological stage and the prognostic nutritional index as independent prognostic factors. The frequency of postoperative complications tended to be higher in patients with a low prognostic nutritional index.The prognostic nutritional index is an independent prognostic factor for survival of patients with completely resected non-small cell lung cancer

Survival curve according to the prognostic nutritional index.

<p>The survival of patients with a low prognostic nutritional index (< 50) was significantly poorer than that of patients with a high prognostic nutritional index (≥50).</p

Patient Characteristics.

<p>AD, adenocarcinoma; CEA, carcinoembryonic antigen; n, number of patients; PNI, prognostic nutritional index; SQ, squamous cell carcinoma.</p><p>Patient Characteristics.</p

Relationship between PNI and postoperative complications.

<p>PNI: prognostic nutritional index</p><p>Other pulmonary events include three cases of interstitial pneumonia and one case of chronic obstructive pulmonary disease exacerbation.</p><p>Relationship between PNI and postoperative complications.</p

Survival curve according to the prognostic nutritional index in patients with pathological stage I disease.

<p>The survival of patients with a low prognostic nutritional index (< 49) was significantly different from those with a high prognostic nutritional index (≥49).</p

Relationship between PNI and clinico-pathological features.

<p>AD, adenocarcinoma; PNI, prognostic nutritional index; SQ, squamous cell carcinoma.</p><p>Relationship between PNI and clinico-pathological features.</p

Univariate analysis of postoperative complications.

<p>AD, adenocarcinoma; CEA, carcinoembryonic antigen; CI, confidence interval; HR, hazard ratio; N, number of patients showing postoperative complications; PNI, prognostic nutritional index.</p><p>Univariate analysis of postoperative complications.</p