Expression and purification of pneumococcal surface protein a of clade 4 in Escherichia coli using hydroxylapatite and ion-exchange column chromatography

In this study, we describe a simple method to produce PspA of clade 4 from an Escherichia coli expression system using hydroxylapatite and ion-exchange chromatography. Using this method, we successfully expressed soluble PspA4 in 10 L of autoinducing culture medium, with a wet-cell yield of 19 g/L and a final PspA4 concentration of 22.8 mg/L. Additionally, we improved PspA4 purity from 17% to 70% in a single step through the use of hydroxylapatite, resulting in acquisition of recombinant PspA4 (>95% purity) at a final yield of 43% from the starting cell-lysis solution. We subsequently verified the secondary structure molecular weight of recombinant PspA4 by circular dichroism and mass spectrometry, respectively. These results demonstrated a highly efficient method for mass producing PspA4 protein and that can also be applied for purification of PspA proteins from other clades.
Source: Protein Expression and Purification - Category: Biochemistry Source Type: research

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Authors: Rombauts A, Abelenda-Alonso G, Cuervo G, Gudiol C, Carratalà J Abstract INTRODUCTION: Despite adequate antibiotic coverage, community-acquired pneumonia (CAP) remains a leading cause of hospitalization and mortality worldwide. It induces both a local pulmonary and a systemic inflammatory response, particularly significant in severe cases. The intensity of the dysregulated host response varies from patient to patient and has a negative impact on survival and other outcomes. AREAS COVERED: This comprehensive review summarizes the pathophysiological aspects of the inflammatory response in CAP, brie...
Source: Expert Review of Anti-Infective Therapy - Category: Infectious Diseases Tags: Expert Rev Anti Infect Ther Source Type: research
CONCLUSIONS: Xyloglucan/gelose plus ORS was effective and safe in treating acute diarrhea in children. PMID: 33028102 [PubMed - as supplied by publisher]
Source: Expert Review of Gastroenterology and Hepatology - Category: Gastroenterology Tags: Expert Rev Gastroenterol Hepatol Source Type: research
Conclusions: (1) Data at our center suggests at least a regional implementation gap in GBS screening and IAP. (2) The decline in the resistance rate ofE. coli for all antimicrobial substances might indicate that the reduction of prenatal antibiotics use is beneficial and that neonatal antibiotic stewardship programs should include pregnant women as well.What is Known:• GBS screening and intrapartum antibiotic prophylaxis led to a 32%-reduction in GBS disease in Germany with a 0.75 (92:122) ratio of early-onset disease to late-onset disease in 2009–2010.• Prenatal antibiotic use might increase the risk of E....
Source: European Journal of Pediatrics - Category: Pediatrics Source Type: research
ConclusionThe COMQ-12 could be a useful tool to differentiate chronic otitis media with or without cholesteatoma.
Source: European Archives of Oto-Rhino-Laryngology - Category: ENT & OMF Source Type: research
Authors: Tamai H, Shingaki N, Ida Y, Shimizu R, Maeshima S, Okamura J, Kawashima A, Nakao T, Hara T, Matsutani H, Nishikawa I, Higashi K Abstract BACKGROUND: Although clinical use of sofosbuvir plus ribavirin has been approved for patients infected with genotype 2 hepatitis C virus, patients ≥ 75-years-old have not been included in previous clinical trials. AIM: To evaluate the real-world safety and efficacy of sofosbuvir plus ribavirin for elderly patients (≥ 75-years-old) compared to nonelderly patients, we conducted a post-marketing prospective cohort study. METHODS: We treated 265 patients with ge...
Source: World Journal of Hepatology - Category: Gastroenterology Tags: World J Hepatol Source Type: research
Emergency-use authorizations, a formerly obscure corner of regulatory law, have become a centerpiece of the government ’s response to the pandemic.
Source: NYT - Category: American Health Authors: Tags: your-feed-science Coronavirus Risks and Safety Concerns Food and Drug Administration Hahn, Stephen M (1960- ) Coronavirus (2019-nCoV) Vaccination and Immunization Clinical Trials Drugs (Pharmaceuticals) your-feed-health your-feed-healthc Source Type: news
The use of an immune-system stimulant harvested from shark liver oil in the development of some coronavirus vaccines has animal conservationists pressing for alternatives.(Image credit: Reinhard Dirscherl/ullstein bild via Getty Images)
Source: NPR Health and Science - Category: Consumer Health News Authors: Source Type: news
Authors: Yamaya T, Baba T, Hagiwara E, Ikeda S, Niwa T, Kitayama T, Murohashi K, Higa K, Sato Y, Ogura T Abstract Coronavirus disease 2019 (COVID-19) has been recognized as a worldwide pandemic. However, the clinical course of COVID-19 remains poorly characterized. Although some cases of pneumothorax have been reported, they all had pulmonary complications or were managed with mechanical ventilation. We herein report a case of pneumothorax that developed even though the patient had no pulmonary underlying diseases and had never been managed with mechanical ventilation. In the present case, a lung bulla was found on...
Source: Internal Medicine - Category: Internal Medicine Tags: Intern Med Source Type: research
Authors: Takahashi M, Horio Y, Takihara T, Enokida K, Miyaoka M, Hirabayashi K, Ohshinden K, Hattori S, Takahashi F, Takahashi G, Tanaka J, Takiguchi H, Niimi K, Ito Y, Hayama N, Oguma T, Asano K Abstract A 72-year-old man was treated with prednisolone and cyclosporine A for idiopathic pulmonary fibrosis. A nodule with a diameter of 19 mm was found in the right lung and diagnosed as lung squamous cell carcinoma. Anti-cancer treatments were not performed because of the presence of advanced interstitial pneumonia and chronic respiratory failure. Cyclosporine A was tapered to avoid suppression of anti-tumor immunity, ...
Source: Internal Medicine - Category: Internal Medicine Tags: Intern Med Source Type: research
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