Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
LanguageLanguage
-
SubjectSubject
-
Item TypeItem Type
-
DisciplineDiscipline
-
YearFrom:-To:
-
More FiltersMore FiltersIs Peer Reviewed
Done
Filters
Reset
558
result(s) for
"Bergman, Peter"
Sort by:
Vitamin D and Respiratory Tract Infections: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
2013
Low levels of 25-OH vitamin D are associated with respiratory tract infection (RTI). However, results from randomized controlled trials are inconclusive. Therefore, we performed a systematic review and meta-analysis to assess the preventive effect of vitamin D supplementation on RTI.
Randomized, controlled trials of vitamin D for prevention of RTI were used for the analysis. The risks of within-trial and publication bias were assessed. Odds ratios of RTI were pooled using a random-effects model. Heterogeneity was assessed using Cochran's Q and I(2). Meta-regressions and subgroup analyses were used to assess the influence of various factors on trial outcome. The pre-defined review protocol was registered at the PROSPERO international prospective register of systematic reviews, registration number CRD42013003530.
Of 1137 citations retrieved, 11 placebo-controlled studies of 5660 patients were included in the meta-analysis. Overall, vitamin D showed a protective effect against RTI (OR, 0.64; 95% CI, 0.49 to 0.84). There was significant heterogeneity among studies (Cohran's Q p<0.0001, I(2) = 72%). The protective effect was larger in studies using once-daily dosing compared to bolus doses (OR = 0.51 vs OR = 0.86, p = 0.01). There was some evidence that results may have been influenced by publication bias.
Results indicate that vitamin D has a protective effect against RTI, and dosing once-daily seems most effective. Due to heterogeneity of included studies and possible publication bias in the field, these results should be interpreted with caution.
Journal Article
Editorial: B-cell deficiency and infection: exploring humoral immunity’s protective mechanisms
2025
[...]Delgado et al.report on an automated database-guided gating and identification (AGI) approach for the use with multiparameter flow cytometry (FC) immunophenotyping. The AGI tool demonstrated a high degree of correlation with expert-based manual gating, a lower degree of variability, and a significantly reduced time requirement for data analysis compared to manual gating. Conflict of interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Journal Article
Host Directed Therapy Against Infection by Boosting Innate Immunity
by
Bergman, Peter
,
Agerberth, Birgitta
,
Gudmundsson, Gudmundur H.
in
Adaptive immunity
,
Animals
,
antibiotic
2020
The innate immune system constitutes the first line of defense against invading pathogens, regulating the normal microbiota and contributes to homeostasis. Today we have obtained detailed knowledge on receptors, signaling pathways, and effector molecules of innate immunity. Our research constellation has focused on ways to induce the expression of antimicrobial peptides (AMPs), the production of oxygen species (ROS and NO), and to activate autophagy, during the last two decades. These innate effectors, with different mechanisms of action, constitute a powerful defense armament in phagocytes and in epithelial cells. Innate immunity does not only protect the host from invading pathogens, but also regulates the composition of the microbiota, which is an area of intense research. Notably, some virulent bacteria have the capacity to downregulate innate defenses and can thereby cause invasive disease. Understanding the detailed mechanisms behind pathogen-mediated suppression of innate effectors are currently in progress. This information can be of importance for the development of novel treatments based on counteraction of the downregulation; we have designated this type of treatment as host directed therapy (HDT). The concept to boost innate immunity may be particularly relevant as many pathogens are developing resistance against classical antibiotics. Many pathogens that are resistant to antibiotics are sensitive to the endogenous effectors included in early host defenses, which contain multiple effectors working in cooperation to control infections. Here, we review recent data related to downregulation of AMPs by pathogenic bacteria, induction of innate effector mechanisms, including cytokine-mediated effects, repurposed drugs and the role of antibiotics as direct modulators of host responses. These findings can form a platform for the development of novel treatment strategies against infection and/or inflammation.
Journal Article
Low Vitamin D Levels Are Associated with Higher Opioid Dose in Palliative Cancer Patients – Results from an Observational Study in Sweden
by
Bergman, Peter
,
Sperneder, Susanne
,
Bergqvist, Jenny
in
25-Hydroxyvitamin D
,
Adolescent
,
Adult
2015
Vitamin D deficiency is common among palliative cancer patients and has been connected to an increased risk for pain, depressions and infections. Therefore we wanted to test the hypothesis that low 25-hydroxyvitamin D (25OHD) levels are associated with higher opioid dose, higher infectious burden and impaired quality of life in palliative cancer patients. The secondary aim was to investigate the association between 25OHD-levels and survival time.
In this prospective, observational study in palliative cancer-patients (n = 100) we performed univariate and multiple linear regression analysis to assess the association of 25OHD levels with opioid dose, infectious burden (antibiotic consumption), quality of life (Edmonton Symptom Assessment Scale, ESAS) and survival time, controlling for potential confounding factors.
The median 25OHD level was 40 nmol/L (range 8-154 nmol/L). There was a significant association between 25OHD levels and opioid dose, beta coefficient -0.67; p=0.02; i.e. a low 25OHD level was associated with a higher opioid dose. This association remained significant after adjustment for stage of the cancer disease in a multivariate analysis, beta coefficient -0.66; p = 0.04. There was no association between 25OHD levels and antibiotic use or quality of life. Univariate cox regression analysis showed a weak correlation between survival time and 25OHD levels (p<0.05). However, decreased albumin levels and increased CRP levels were superior markers to predict survival time; p<0.001 for both analyses.
Low 25OHD-levels are associated with increased opioid consumption in palliative cancer patients. Future interventional studies are needed to investigate if pain can be reduced by vitamin D supplementation in these patients. In addition, this study confirms previous findings that low albumin and increased CRP levels are useful markers for survival time in palliative cancer patients.
Journal Article
Significant Effects of Oral Phenylbutyrate and Vitamin D3 Adjunctive Therapy in Pulmonary Tuberculosis: A Randomized Controlled Trial
by
Bergman, Peter
,
Arifuzzaman, Abu Saleh Mohammad
,
Agerberth, Birgitta
in
Administration, Oral
,
Adult
,
Analysis
2015
Development of new tuberculosis (TB) drugs and alternative treatment strategies are urgently required to control the global spread of TB. Previous results have shown that vitamin D3 (vitD3) and 4-phenyl butyrate (PBA) are potent inducers of the host defense peptide LL-37 that possess anti-mycobacterial effects.
To examine if oral adjunctive therapy with 5,000IU vitD3 or 2x500 mg PBA or PBA+vitD3 to standard chemotherapy would lead to enhanced recovery in sputum smear-positive pulmonary TB patients.
Adult TB patients (n = 288) were enrolled in a randomized, double-blind, placebo-controlled trial conducted in Bangladesh. Primary endpoints included proportions of patients with a negative sputum culture at week 4 and reduction in clinical symptoms at week 8. Clinical assessments and sputum smear microscopy were performed weekly up to week 4, fortnightly up to week 12 and at week 24; TB culture was performed at week 0, 4 and 8; concentrations of LL-37 in cells, 25-hydroxyvitamin D3 (25(OH)D3) in plasma and ex vivo bactericidal function of monocyte-derived macrophages (MDM) were determined at week 0, 4, 8, 12 and additionally at week 24 for plasma 25(OH)D3.
At week 4, 71% (46/65) of the patients in the PBA+vitD3-group (p = 0.001) and 61.3% (38/62) in the vitD3-group (p = 0.032) were culture negative compared to 42.2% (27/64) in the placebo-group. The odds of sputum culture being negative at week 4 was 3.42 times higher in the PBA+vitD3-group (p = 0.001) and 2.2 times higher in vitD3-group (p = 0.032) compared to placebo. The concentration of LL-37 in MDM was significantly higher in the PBA-group compared to placebo at week 12 (p = 0.034). Decline in intracellular Mtb growth in MDM was earlier in the PBA-group compared to placebo (log rank 11.38, p = 0.01).
Adjunct therapy with PBA+vitD3 or vitD3 or PBA to standard short-course therapy demonstrated beneficial effects towards clinical recovery and holds potential for host-directed-therapy in the treatment of TB.
clinicaltrials.gov NCT01580007.
Journal Article
Antibiotic Treatment in End-of-Life Cancer Patients—A Retrospective Observational Study at a Palliative Care Center in Sweden
by
Helde-Frankling, Maria
,
Bergman, Peter
,
Bergqvist, Jenny
in
Antibiotics
,
Cancer
,
Hospice care
2016
Background: The aim of this study was to elucidate whether palliative cancer patients benefit from antibiotic treatment in the last two weeks of life when an infection is suspected. Method: We reviewed medical records from 160 deceased palliative cancer patients that had been included in previous studies on vitamin D and infections. Patients treated with antibiotics during the last two weeks of life were identified and net effects of treatment (symptom relief) and possible adverse events were extracted from medical records. Results: Seventy-nine patients (49%) had been treated with antibiotics during the last two weeks in life. In 37% (n = 29), the treatment resulted in evident symptom relief and among these 50% had a positive bacterial culture, 43% had a negative culture and in 7% no culture was taken. Among the patients with no or unknown effect of antibiotics, 50% had a positive culture. When the indication for antibiotic treatment was to avoid or treat sepsis, symptom relief was achieved in 50% of the patients (n = 19). Only 4% (n = 3) of the patients experienced adverse events of the treatment (diarrhea, nausea). Conclusions: Treating infections with antibiotics in the last weeks of life may improve the quality of life for palliative cancer patients, especially if sepsis is suspected or confirmed. According to our results, the beneficial effects outweigh the potentially negative outcomes.
Journal Article
Red meat intake in chronic kidney disease patients: Two sides of the coin
by
Bergman, Peter
,
Mafra, Denise
,
Lindholm, Bengt
in
Amino acids
,
Animal protein
,
Atherosclerosis
2018
Red meat is an important dietary source of high biological value protein and micronutrients such as vitamins, iron, and zinc that exert many beneficial functions. However, high consumption of animal protein sources, especially red meat, results in an increased intake of saturated fat, cholesterol, iron, and salt, as well as an excessive acid load. Red meat intake may lead to an elevated production of uremic toxins by the gut microbiota, such as trimethylamine n-oxide (TMAO), indoxyl sulfate, and p-cresyl sulfate. These uremic toxins are associated with increased risk for cardiovascular (CV) mortality. Limiting the intake of red meat in patients with chronic kidney disease (CKD) thus may be a good strategy to reduce CV risk, and may slow the progression of kidney disease. In the present review, we discuss the role of red meat in the diet of patients with CKD. Additionally, we report on a pilot study that focused on the effect of a low-protein diet on TMAO plasma levels in nondialysis CKD patients.
•Red meat is a valuable source of essential amino acids and micronutrients for patients with chronic kidney disease (CKD).•Red meat intake may lead to elevated production of uremic toxins and increased cardiovascular risk.•High red meat intake is associated with increased risk for progression of CKD.•Red meat intake should be limited in patients with CKD.
Journal Article
Bile acid metabolites enhance expression of cathelicidin antimicrobial peptide in airway epithelium through activation of the TGR5-ERK1/2 pathway
2024
Signals for the maintenance of epithelial homeostasis are provided in part by commensal bacteria metabolites, that promote tissue homeostasis in the gut and remote organs as microbiota metabolites enter the bloodstream. In our study, we investigated the effects of bile acid metabolites, 3-oxolithocholic acid (3-oxoLCA), alloisolithocholic acid (AILCA) and isolithocholic acid (ILCA) produced from lithocholic acid (LCA) by microbiota, on the regulation of innate immune responses connected to the expression of host defense peptide cathelicidin in lung epithelial cells. The bile acid metabolites enhanced expression of cathelicidin at low concentrations in human bronchial epithelial cell line BCi-NS1.1 and primary bronchial/tracheal cells (HBEpC), indicating physiological relevance for modulation of innate immunity in airway epithelium by bile acid metabolites. Our study concentrated on deciphering signaling pathways regulating expression of human cathelicidin, revealing that LCA and 3-oxoLCA activate the surface G protein-coupled bile acid receptor 1 (TGR5, Takeda-G-protein-receptor-5)—extracellular signal-regulated kinase (ERK1/2) cascade, rather than the nuclear receptors, aryl hydrocarbon receptor, farnesoid X receptor and vitamin D3 receptor in bronchial epithelium. Overall, our study provides new insights into the modulation of innate immune responses by microbiota bile acid metabolites in the gut-lung axis, highlighting the differences in epithelial responses between different tissues.
Journal Article
Studies on the Antibacterial Effects of Statins - In Vitro and In Vivo
by
Bergman, Peter
,
Pütsep, Katrin
,
Pohanka, Anton
in
Analysis
,
Anti-Bacterial Agents - pharmacology
,
Antibiotics
2011
Statin treatment has been associated with a beneficial outcome on respiratory tract infections. In addition, previous in vitro and in vivo experiments have indicated favorable effects of statins in bacterial infections.
The aim of the present study was to elucidate possible antibacterial effects of statins against primary pathogens of the respiratory tract.
MIC-values for simvastatin, fluvastatin and pravastatin against S. pneumoniae, M. catarrhalis and H. influenzae were determined by traditional antibacterial assays. A BioScreen instrument was used to monitor effects of statins on bacterial growth and to assess possible synergistic effects with penicillin. Bacterial growth in whole blood and serum from healthy volunteers before and after a single dose of simvastatin, fluvastatin and penicillin (positive control) was determined using a blood culture system (BactAlert).
The MIC-value for simvastatin against S pneumoniae and M catarrhalis was 15 µg/mL (36 mmol/L). Fluvastatin and Pravastatin showed no antibacterial effect in concentrations up to 100 µg/mL (230 µmol/L). Statins did not affect growth or viability of H influenzae. Single doses of statins given to healthy volunteers did not affect growth of pneumococci, whereas penicillin efficiently killed all bacteria.
Simvastatin at high concentrations 15 µg/mL (36 µmol/L) rapidly kills S pneumoniae and M catarrhalis. However, these concentrations by far exceed the concentrations detected in human blood during simvastatin therapy (1-15 nmol/L) and single doses of statins given to healthy volunteers did not improve antibacterial effects of whole blood. Thus, a direct bactericidal effect of statins in vivo is probably not the mechanism behind the observed beneficial effect of statins against various infections.
Journal Article
Variations in biomarkers of dyslipidemia and dysbiosis during the menstrual cycle: a pilot study in healthy volunteers
by
Ekström, Lena
,
Bergman, Peter
,
Warnqvist, Anna
in
Apolipoprotein B (ApoB)
,
Apolipoproteins
,
Atherosclerosis
2021
Background
Dyslipidemia in metabolic syndrome may introduce an underestimation of the risk for cardiovascular disease (CVD) using Low-Density Lipoprotein-Cholesterol (LDL-C) as a surrogate marker. Recently, non-High-Density Lipoprotein-Cholesterol (non-HDL-C), Apolipoprotein B (ApoB) and remnant-Cholesterol (remnant-C) have been suggested as better biomarkers for dyslipidemia. In addition, the microbial metabolites trimethylamine-N-oxide (TMAO), betaine and choline have been associated with CVD and suggested as markers for dysbiosis. There is a lack of knowledge on potential alterations in these biomarkers during the menstrual cycle. The aim of this single center, prospective non-interventional study, was to investigate variations in biomarkers of dyslipidemia and dysbiosis in healthy volunteers during the menstrual cycle.
Method
Serum samples were collected from 17 healthy, regularly menstruating women during two menstrual cycles, including the follicular, ovulatory and luteal phases. Levels of lipoproteins, lipoprotein ratios and microbial metabolites were analyzed in a total of 90 samples (30 complete menstrual cycles).
Results
ApoB, ApoB/HDL and non-HDL-C/HDL ratios were significantly higher in the follicular phase compared to the ovulatory and luteal phases (
p
< 0.05). Remnant-C were higher during the luteal phase (
p
< 0.05). TMAO did not vary during the different phases and did not correlate with estrogen levels.
Conclusion
Our data support that biomarkers for dyslipidemia vary during the menstrual cycle. Thus, to avoid an underestimation of cardiovascular risk, sampling during the follicular phase, when levels of pro-atherogenic lipids are higher, may be considered.
Journal Article