| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Skoglund, A., et al.
(författare)
-
Functional analysis of the M.HpyAIV DNA methyltransferase of Helicobacter pylori
- 2007
-
Ingår i: Journal of Bacteriology. - 0021-9193 .- 1098-5530. ; 189:24, s. 8914-8921
-
Tidskriftsartikel (refereegranskat)abstract
- A large number of genes encoding restriction-modification (R-M) systems are found in the genome of the human pathogen Helicobacter pylori. R-M genes comprise approximately 10% of the strain-specific genes, but the relevance of having such an abundance of these genes is not clear. The type II methyltransferase (MTase) M.HpyAIV, which recognizes GANTC sites, was present in 60% of the H. pylori strains analyzed, whereof 69% were resistant to restriction enzyme digestion, which indicated the presence of an active MTase. H. pylori strains with an inactive M.HpyAIV phenotype contained deletions in regions of homopolymers within the gene, which resulted in premature translational stops, suggesting that M.HpyAIV may be subjected to phase variation by a slipped-strand mechanism. An M.HpyAIV gene mutant was constructed by insertional mutagenesis, and this mutant showed the same viability and ability to induce interleukin-8 in epithelial cells as the wild type in vitro but had, as expected, lost the ability to protect its self-DNA from digestion by a cognate restriction enzyme. The M.HpyAIV from H. pylori strain 26695 was overexpressed in Escherichia coli, and the protein was purified and was able to bind to DNA and protect GANTC sites from digestion in vitro. A bioinformatic analysis of the number of GANTC sites located in predicted regulatory regions of H. pylori strains 26695 and J99 resulted in a number of candidate genes. katA, a selected candidate gene, was further analyzed by quantitative real-time reverse transcription-PCR and shown to be significantly down-regulated in the M.HpyAIV gene mutant compared to the wild-type strain. This demonstrates the influence of M.HpyAIV methylation in gene expression.
|
|
| 5. |
- Andersson, Agnes, et al.
(författare)
-
Headache Before and After Endoscopic Transsphenoidal Pituitary Tumor Surgery: A Prospective Study
- 2022
-
Ingår i: Journal of Neurological Surgery Part B-Skull Base. - : Georg Thieme Verlag KG. - 2193-6331 .- 2193-634X. ; 83:suppl. 2
-
Tidskriftsartikel (refereegranskat)abstract
- Objective Headache is a common symptom among patients with pituitary tumors, as it is in the general population. The aim of the study was to investigate headache as a symptom in patients with pituitary tumors before and 6 months after endoscopic transsphenoidal surgery (TSS). Design This is a prospective observational cohort study. Setting This study was conducted at university tertiary referral hospital. Participants A total of 110 adult patients underwent endoscopic TSS for pituitary tumors. Main Outcome Measures The Migraine Disability Assessment (MIDAS) questionnaire was used before and 6 months after surgery for the assessment of headache. Clinical variables with potential influence on headache were analyzed. Results Sixty-eight (62%) patients experienced headaches at least once during the 3 months before surgery. Thirty (27%) patients reported disabling headache before surgery, with younger age being an independent associated factor ( p <0.001). In patients with disabling headache before surgery, the median (interquartile range) MIDAS score improved from 78 (27-168) to 16 (2-145; p =0.049), headache frequency decreased from 45 (20-81) to 14 (4-35) days ( p =0.009), and headache intensity decreased from 6 (5-8) to 5 (4-7) ( p =0.011) after surgery. In total, 16 of the 30 (53%) patients reported a clinically relevant improvement and five (17%) a clinically relevant worsening. Four (5%) patients developed new disabling headache. No predictor for postoperative improvement of headache was identified. Conclusion In this prospective study, the results show that disabling headache improves following endoscopic TSS in a subset of patients with pituitary tumors. However, no predictive factors for improvement could be identified.
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
- Hober, Sophia, Professor, 1965-, et al.
(författare)
-
Systematic evaluation of SARS-CoV-2 antigens enables a highly specific and sensitive multiplex serological COVID-19 assay
- 2021
-
Ingår i: Clinical & Translational Immunology. - : Wiley. - 2050-0068. ; 10:7
-
Tidskriftsartikel (refereegranskat)abstract
- Objective. The COVID-19 pandemic poses an immense need for accurate, sensitive and high-throughput clinical tests, and serological assays are needed for both overarching epidemiological studies and evaluating vaccines. Here, we present the development and validation of a high-throughput multiplex bead-based serological assay. Methods. More than 100 representations of SARS-CoV-2 proteins were included for initial evaluation, including antigens produced in bacterial and mammalian hosts as well as synthetic peptides. The five best-performing antigens, three representing the spike glycoprotein and two representing the nucleocapsid protein, were further evaluated for detection of IgG antibodies in samples from 331 COVID-19 patients and convalescents, and in 2090 negative controls sampled before 2020. Results. Three antigens were finally selected, represented by a soluble trimeric form and the S1-domain of the spike glycoprotein as well as by the C-terminal domain of the nucleocapsid. The sensitivity for these three antigens individually was found to be 99.7%, 99.1% and 99.7%, and the specificity was found to be 98.1%, 98.7% and 95.7%. The best assay performance was although achieved when utilising two antigens in combination, enabling a sensitivity of up to 99.7% combined with a specificity of 100%. Requiring any two of the three antigens resulted in a sensitivity of 99.7% and a specificity of 99.4%. Conclusion. These observations demonstrate that a serological test based on a combination of several SARS-CoV-2 antigens enables a highly specific and sensitive multiplex serological COVID-19 assay.
|
|
| 9. |
|
|
| 10. |
- Lundahl, B, et al.
(författare)
-
Microsomal triglyceride transfer protein -493T variant reduces IDL plus LDL apoB production and the plasma concentration of large LDL particles
- 2006
-
Ingår i: American journal of physiology. Endocrinology and metabolism. - : American Physiological Society. - 0193-1849 .- 1522-1555. ; 290:4, s. E739-E745
-
Tidskriftsartikel (refereegranskat)abstract
- The microsomal triglyceride transfer protein (MTP) is essential for the synthesis and secretion of apolipoprotein B (apoB)-containing lipoproteins. We investigated the role the MTP −493G/T gene polymorphism in determining the apoB-100 secretion pattern and LDL heterogeneity in healthy human subjects. Groups of carriers of the T and the G variants ( n = 6 each) were recruited from a cohort of healthy 50-yr-old men. Kinetic studies were performed by endogenous [2H3]leucine labeling of apoB and subsequent quantification of the stable isotope incorporation. apoB production rates, metabolic conversions, and eliminations were calculated by multicompartmental modeling (SAAM-II). LDL subfraction distribution was analyzed in the entire cohort ( n = 377). Carriers of the MTP −493T allele had lower plasma LDL apoB and lower concentration of large LDL particles [LDL-I: 136 ± 57 (TT) vs. 175 ± 55 (GG) mg/l, P < 0.01]. Kinetic modeling suggested that MTP −493T homozygotes had a 60% lower direct production rate of intermediate-density lipoprotein (IDL) plus LDL compared with homozygotes for the G allele ( P < 0.05). No differences were seen in production rates of large and small VLDL, nor were there any differences in metabolic conversion or elimination rates of apoB between the genotype groups. This study shows that a polymorphism in the MTP gene affects the spectrum of endogenous apoB-containing lipoprotein particles produced in humans. Reduced direct production of LDL plus IDL appears to be related to lower plasma concentrations of large LDL particles.
|
|
