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Microbial communities exhibit spatial structure at different scales, due to constant interactions with their environment and dispersal limitation. While this spatial structure is often considered in studies focusing on free-living environmental communities, it has received less attention in the context of host-associated microbial communities or microbiota. The wider adoption of methods accounting for spatial variation in these communities will help to address open questions in basic microbial ecology as well as realize the full potential of microbiome-aided medicine. Here, we first overview known factors affecting the composition of microbiota across diverse host types and at different scales, with a focus on the human gut as one of the most actively studied microbiota. We outline a number of topical open questions in the field related to spatial variation and patterns. We then review the existing methodology for the spatial modelling of microbiota. We suggest that methodology from related fields, such as systems biology and macro-organismal ecology, could be adapted to obtain more accurate models of spatial structure. We further posit that methodological developments in the spatial modelling and analysis of microbiota could in turn broadly benefit theoretical and applied ecology and contribute to the development of novel industrial and clinical applications.

The current classification of hypertension does not reflect the heterogeneity in characteristics or cardiovascular outcomes of hypertensive individuals. Our objective was to identify distinct phenotypes of hypertensive individuals with potentially different cardiovascular risk profiles using data‐driven cluster analysis. We performed clustering, a procedure that identifies groups with similar characteristics, in 3726 individuals (mean age 59.4 years, 49% women) with grade 2 hypertension (blood pressure ≥160/100 mmHg or antihypertensive medication) selected from FINRISK 1997, 2002, and 2007 cohorts. We computed clusters based on eight factors associated with hypertension: mean arterial pressure, pulse pressure, non‐high‐density lipoprotein cholesterol, blood glucose, BMI, C‐reactive protein, estimated glomerular filtration rate, and alcohol. After that, we used Cox regression models adjusted for age and sex to assess the relative risk of cardiovascular disease (CVD) outcomes between the clusters and a reference group of 11 020 individuals. We observed two comparable clusters in both men and women. The Metabolically Challenged (MC) cluster was characterized by high blood glucose (Z‐score 4.4 ± 1.1 vs 0.2 ± 0.8, men; 3.5 ± 1.1 vs 0.0 ± 0.6, women) and elevated BMI (30.4 ± 4.1 vs 28.9 ± 4.3, men; 32.7 ± 4.9 vs 29.3 ± 5.5, women). Over a 10‐year follow‐up (1034 CVD events), MC had 1.6‐fold (95% CI 1.1‐2.4) CVD risk compared to non‐MC and 2.5‐fold (95% CI 1.7‐3.7) CVD risk compared to the reference group (P ≤ .009 for both). Using unsupervised hierarchical clustering, we found two phenotypically distinct hypertension subgroups with different risks of CVD complications. This substratification could be used to design studies that explore the differential effects of antihypertensive therapies among subgroups of hypertensive individuals.

Background Statins have anticancer effects on prostate cancer both in vitro and in vivo. It is unclear whether this is due to systemic cholesterol-lowering or direct local growth inhibition in the prostate. It is also unclear whether statins can access the prostate; lipophilic statins could, in theory, pass lipid-enriched cell membranes by passive diffusion. However, statin concentrations in the human prostate have not been measured before. Methods The study population was based on a randomized clinical trial where 158 men with prostate cancer were randomized to use 80 mg atorvastatin (ATV) or placebo daily for a median of 27 days before radical prostatectomy. ATV and atorvastatin lactone (ATV-Lactone) concentrations in the plasma and in the prostate were measured with mass spectrometry in men randomized to the ATV arm. Linear trends between intraprostatic concentration and plasma concentration, body mass index, age, and duration of intervention were examined. The relative tissue concentrations of ATV and ATV-Lactone were calculated in prostatic tissue and plasma to evaluate drug homeostasis. Subgroup analyses were stratified by tumor and population characteristics. Results The analysis involved a total of 55 men. When limited to men whose tissue concentrations of ATV was measurable (n = 28, 50%), median ATV concentration was 212% higher in the tissue (median concentration 17.6 ng/g) compared to the plasma (median concentration 3.6 ng/mL). Also, ATV-L concentration was 590% higher in the tissue as compared to the plasma concentration. No statistically significant linear trends between the plasma and tissue concentrations were observed. When comparing the relative concentration of atorvastatin lactone over ATV, the concentrations were in balance in the plasma, In the prostate, however, the relative concentration of atorvastatin lactone was 57% lower compared to ATV (P = .009 for the difference between prostate tissue and plasma). No effect modification by tumor or population characteristics was observed. Conclusions Measurable ATV concentrations in the prostate support ATV's ability to access the prostate from the circulation. ATV may accumulate in the prostate as intraprostatic concentrations are elevated compared to the plasma concentration.

Background Improved prostate cancer (PCa) survival by statin use has been reported among PCa patients managed with radiation or androgen deprivation therapy (ADT), while results are controversial for men managed surgically. We evaluate the association between cholesterol-lowering medication with initiation of ADT and disease-specific death among PCa cases who underwent radical prostatectomy in Finland between 1995 and 2013. Methods The study cohort included 14 424 men with PCa who underwent radical prostatectomy in Finland between 1995 and 2013. Cases were identified from national hospital discharge registry. Clinical data were amended from patient files of the treating hospitals. Information on co-morbidities, additional radiation- or chemotherapy, and causes of deaths were collected from national registries. Personal-level data on medication use during 1995-2014 were gathered from national prescription database. Registry linkages were carried out using personal identification number. Lipid-lowering drugs were categorized into statins and non-statin drugs. Risk of PCa death and initiation of ADT was analyzed using Cox-regression model with adjustment for age, radiation therapy, chemotherapy, co-morbidities and other drug use. Statin use was analyzed as time-dependent variable. Delayed risk associations were evaluated in lag-time analysis. Results Compared to non-users the risk of PCa death was significantly lower among statin users before PCa diagnosis (HR 0.70, 95%CIs 0.52-0.95). For statin use after PCa diagnosis the risk was lowered in age-adjusted analysis (HR 0.76 95%CIs 0.62-0.93) but not after multivariable-adjustment. Post-diagnostic statin use was associated with improved PCa-specific survival in 1, 3 and 5 years lag-time analyses. The risk reduction was clearest for statin use initiated 5 years earlier (HR 0.71 95%CIs 0.55-0.92). Use of statins both before and after PCa diagnosis was associated with reduced risk of ADT use (HR 0.72 95%CIs 0.65-0.80 and HR 0.73, 95%CI 0.67-0.80, respectively). The risk of ADT decreased by increasing intensity of statin use before diagnosis. Conclusion Statin use among surgically treated PCa patients has significant association with decreased risk of starting ADT and PCa death. The risk is lowered especially among men with statin use before PCa diagnosis and in men who used statins at high-dose. Our results are hypothesis generating due to retrospective study design.

Background Studies conducted in farm environments suggest that diverse microbial exposure promotes children's lung health. The underlying mechanisms are unclear, and the development of asthma-preventive strategies has been delayed. More comprehensive investigation of the environment-induced immunoregulation is required for better understanding of asthma pathogenesis and prevention. Exposure to air pollution, including particulate matter (PM), is a risk factor for asthma, thus providing an excellent counterpoint for the farm-effect research. Lack of comparable data, however, complicates interpretation of the existing information. We aimed to explore the immunoregulatory effects of cattle farm dust (protective, Finland) and urban air PM (high-risk, China) for the first time using identical research methods. Methods We stimulated PBMCs of 4-year-old children (N = 18) with farm dust and size-segregated PM and assessed the expression of immune receptors CD80 and ILT4 on dendritic cells and monocytes as well as cytokine production of PBMCs. Environmental samples were analysed for their composition. Results Farm dust increased the percentage of cells expressing CD80 and the cytokine production of children's immune cells, whereas PM inhibited the expression of important receptors and the production of soluble mediators. Although PM samples induced parallel immune reactions, the size-fraction determined the strength of the effects. Conclusions Our study demonstrates the significance of using the same research framework when disentangling shared and distinctive immune pathways operating in different environments. Observed stimulatory effects of farm dust and inhibitory effects of PM could shape responses towards respiratory pathogens and allergens, and partly explain differences in asthma prevalence between studied environments.

Tutkielmaan liittyva artikkeli / Article related to the thesis: Antihypertensive drugs and prostate cancer survival after radical prostatectomy in Finland - A nationwide cohort study. International journal of cancer, 2018 Aug 15., DOI: 10.1002/ijc.31802

Breast cancer (BC) and diabetes mellitus (DM) are major health problems. We examined the association between DM and BC stage at diagnosis and subsequent survival in a Finnish cohort of female BC patients. All BC cases (N = 73,170) diagnosed in 1995-2013 with dates and causes of death were identified from the Finnish Cancer Registry. Participation in organized mammography screening was obtained from Mass Inspection Registry. Information on DM diagnoses and background conditions recorded during 1995-2013 were obtained from national Care Register for Health Care and merged to data on medication use from the national Prescription Register. Logistic regression with adjustment for mammography screening and age at BC diagnosis was used to evaluate the risk of advanced stage BC at diagnosis. Cox regression was used to evaluate overall and BC survival. Analyses were adjusted for age, background conditions and mammography screening. Survival analyses were further adjusted for tumor extent, histology and primary treatment. Of the cohort 11,676 (16.0%) had DM. Screening participation did not differ by diabetes. Compared to non-diabetic women, diabetics had more often locally advanced (odds ratio, OR 1.26; 95% CI 1.18-1.35) or metastatic BC (OR 1.59; 95% CI 1.44-1.75) at diagnosis. During a median follow-up of 5.8 years after BC diagnosis 10,900 (14.9%) women died of BC. Risk of BC death was higher among diabetic compared to non-diabetic women (HR 1.36; 95% CI 1.27-1.46). Risk of BC death increased with duration of DM. This supports DM as a risk factor for fatal BC.

BACKGROUND The prognostic role of preoperative serum lipid levels in patients undergoing radical prostatectomy (RP) for clinically localized prostate cancer (PCa) is unclear. The aim of the present study was to investigate preoperative serum lipid levels in patients with clinically localized PCa undergoing RP and their association with clinicopathological features and oncological outcome. METHODS Preoperative lipid levels (total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides) and statin use from consecutive patients with clinically localized PCa undergoing RP in a tertiary referral center between 2008 and 2015 were recorded and patients were followed prospectively. Logistic regression analysis was used to test the association between lipid levels and clinicopathological parameters. Lipid values were analyzed both as continuous and dichotomized variables. Univariable and multivariable Cox regression analyses were performed to identify predictors for recurrence-free survival (RFS). Recurrence was defined as rising and verified PSA levels >0.1 ng/ml. RESULTS Our cohort consisted of 371 men with a median age of 63 years (range 41-78 years) and a median preoperative PSA value of 6.79 ng/ml (0.43-81.4 ng/ml). Median follow-up was 28 months (1-64). No association was found between lipid levels and adverse pathological characteristics such as ≥pT3, Gleason score ≥8, positive nodal status and positive surgical margins. Recurrence occurred in 49 patients (15.4%) at a median time of 18 months (2-51 month). Compared to low LDL cholesterol, high LDL cholesterol was associated with longer RFS in univariable analysis (continuous: Hazard Ratio (HR): 0.67, 95%-Confidence Interval (CI): 0.47-0.96, P = 0.03; 3 mM cut-point: HR: 0.44, 95%-CI: 0.24-0.79, P = 0.006). Neither levels of other lipids, nor statin use were associated with RFS. Preoperative LDL cholesterol remained an independent predictor for PCa recurrence in a multivariable model adjusted for age, preoperative PSA, statin use, tumor stage, Gleason score, nodal status and surgical margin status (continuous: HR: 0.66, 95%-CI: 0.44-0.99, P = 0.04; 3 mM cut-point: HR: 0.41, 95%-CI: 0.21-0.78, P = 0.007). CONCLUSIONS This is the first prospective study showing the potential adverse and independent prognostic role of low preoperative LDL cholesterol levels in patients with localized PCa undergoing RP. Prostate © 2017 Wiley Periodicals, Inc.

Implantation of a biomaterial provides an adhesion substratum both to host cell integration and to contaminating bacteria. We studied simultaneous competitive adhesion of Staphylococcus aureus in serial 1:10 dilutions of 108 colony forming units (CFU)/mL and human osteogenic sarcoma (SaOS-2) or primary osteoblast (hOB) cells, both 1x105 cells/mL, to the surfaces of titanium, polydimethylsiloxane and polystyrene. The bacterial adherence and human cell proliferation, cytotoxicity and production of reactive oxygen species (ROS) were studied using fluorometric (fluorescent microscopy and flow cytometry) and colorimetric methods (MTT, LDH and crystal violet). The bacterial cell viability was also evaluated using the drop plate method. The presence of bacteria resulted in reduced adherence of human cells to the surface of the biomaterials, increased production of ROS, and into increased apoptosis. On the other hand, the presence of either type of human cells was associated with a reduction of bacterial colonization of the biomaterial with Staphylococcus aureus. These results suggest that increasing colonization of the biomaterial surface in vitro by one negatively affects colonization by the other. Host cell integration to an implant surface reduces bacterial contamination, which opens novel opportunities for the design of infection-resistant biomaterials in current implantology and future regenerative medicine. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 62-72, 2017.

Randomized clinical trials have shown that use of 5α-reductase inhibitors (5-ARIs) lowers overall prostate cancer (PCa) risk compared to placebo, while the proportion of Gleason 8-10 tumors is elevated. It is unknown whether this affects PCa-specific survival. We studied disease-specific survival by 5-ARI usage in a cohort of 6,537 prostate cancer cases diagnosed in the Finnish Prostate Cancer Screening Trial and linked to the national prescription database for information on medication use. Cox proportional hazards regression was used to estimate hazard ratios and 95% confidence intervals for prostate cancer-specific deaths. For comparison, survival among alpha-blocker users was also evaluated. During the median follow-up of 7.5 years after diagnosis a total of 2,478 men died; 617 due to prostate cancer and 1,861 due to other causes. The risk of prostate cancer death did not differ between 5-ARI users and nonusers (multivariable adjusted HR 0.94, 95% CI 0.72-1.24 and HR 0.98, 95% CI 0.69-1.41 for usage before and after the diagnosis, respectively). Alpha-blocker usage both before and after diagnosis was associated with increased risk of prostate cancer death (HR 1.29, 95% CI 1.08-1.54 and HR 1.56, 95% CI 1.30-1.86, respectively). The risk increase vanished in long-term alpha-blocker usage. Use of 5-ARIs does not appear to affect prostate cancer mortality when used in management of benign prostatic hyperplasia. Increased risk associated with alpha-blocker usage should prompt further exploration on the prognostic role of lower urinary tract symptoms.

This is the pre-peer reviewed version of the following article: ”Statin Use and Risk of Disease Recurrence and Death After Radical Prostatectomy”, which has been published in final form at The Prostate 76:469–478 (2016), DOI 10.1002/pros.23138. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.

Objectives/Hypothesis Dysphagia may cause concern about malignancy. Symptoms are often unspecific; thus, it is essential to identify those requiring further investigations. Study Design Retrospective study combined with patient survey. Methods Case records of the 303 dysphagia patients referred in 2009 to Helsinki University Hospital, Department of Otorhinolaryngology–Head and Neck Surgery were surveyed. Based on clinical data, the main cause of symptoms divided patients into five groups. Alarming signs were food sticking in the throat or in the esophagus, weight loss, and progressive dysphagia symptoms. A questionnaire sent 3 years after the primary visit concerned the present symptoms. To investigate whether dysphagia could have been early symptom of malignancy, we surveyed the Finnish Cancer Registry database until the end of 2012. Results Most diagnoses remained descriptive: unspecific dysphagia (167, 55%). Five (0.02%) had malignant disease, for all of whom the suspicion of malignancy was evident. Finnish Cancer Registry data indicated that unspecific dysphagia did not develop into malignancy during a 3-year follow-up. Returned questionnaires numbered 154 (62%), of which 30 (19%) were asymptomatic patients; relieved symptoms in 36 (23%), fluctuating or unchanged symptoms in 43 (28%), and worse symptoms in 12 (8%). The remaining patients (33, 21%) had not answered that question or the answer was uninterpretable. Conclusion Further investigations to reveal malignancy seemed unnecessary if alarming clinical signs or findings were lacking. After 3 years, almost half the patients were asymptomatic or had milder symptoms revealing the condition's potential for spontaneous recovery. Level of Evidence N/A. Laryngoscope, 2015

The authors investigated whether a genetic risk score (GRS) constructed of 32 single nucleotide polymorphisms would predict incident hypertension and blood pressure (BP) change over time in a population cohort during an 11-year follow-up (n=5402 at baseline, 3266 at follow-up). In multivariable models, GRS was associated with higher systolic/diastolic BP values at baseline (β±standard error [SE], 1.04±0.14/1.11±0.13 mm Hg; P

Background Growing evidence suggests that aspirin is associated with decreased prostate cancer (PCa) mortality. The effect of other NSAID use on risk of PCa death remains controversial. We examined prostate cancer survival among aspirin and other NSAID users in the Finnish Prostate Cancer Screening Trial. Methods A total of 6,537 men were diagnosed with prostate cancer in 1996–2009 among the 80,144 men in the trial and 617 died from prostate cancer during the median follow-up of 7.5 years after the diagnosis. Prescription drug purchases information was obtained from the national reimbursement database. We calculated hazard ratios and 95% confidence intervals for PCa-specific survival using multivariable-adjusted Cox regression analysis separately for NSAID and aspirin usage before and after the diagnosis. Results We observed an increased risk of PCa death associated with both pre- and post-diagnostic NSAID usage (HR 1.30, 95%CI 1.07–1.58 and HR 2.09, 95%CI 1.75–2.50, respectively). An increasing risk trend was observed by cumulative dose and intensity of NSAID use. When the last three years were excluded from the analysis, the death risk diminished to a protective level (HR 0.42, 95%CI 0.34–0.51 and HR 0.30 95%CI 0.24–0.39). Aspirin use was not significantly associated with prostate cancer survival. Conclusions The survival decrease among NSAID users is likely explained by symptomatic treatment of metastatic pain in patients with advanced PCa. However, results of the lag time analysis support previous findings of a possible preventative action of NSAIDs. Prostate 75:1394–1402, 2015. © 2015 Wiley Periodicals, Inc.

Antiarrhythmic drug digoxin has been reported to have apoptosis-inducing and cytotoxic effects on prostate cancer cells. We evaluated the association between antiarrhythmic drug use and prostate cancer risk in a population-based case-control study. The study included all new prostate cancer cases diagnosed in Finland during 1995-2002 and matched controls (24,657 case-control pairs) obtained from the Finnish Cancer Registry and the Population Register Center, respectively. Information on antiarrhythmic drug purchases was obtained from national prescription database. Multivariable-adjusted conditional logistic regression model was used for data analysis. Compared to never-users of antiarrhythmic drugs, we found no significant association between digoxin use and prostate cancer risk overall [odds ratio (OR) 0.95, 95% confidence interval (CI): 0.89-1.01] or for advanced prostate cancer risk (OR: 0.90, 95% CI: 0.77-1.05). The result was similar also for other antiarrhythmic drugs, with the exception of sotalol, users of which had decreased risk of advanced prostate cancer (OR: 0.73, 95% CI: 0.56-0.96). Also the overall prostate cancer risk decreased by duration of sotalol use (p for trend 0.038). We show that digoxin or other common antiarrhythmic drugs generally do not associate with prostate cancer risk at population level during maximum follow-up of eight years. However, we cannot rule out longer term protective effects of digoxin. K(+) -channel blocker sotalol shows some promise as prostate cancer preventing agent. However, findings need to be confirmed in further studies.

BACKGROUND Two clinical trials have shown that users of 5α-reductase inhibitors finasteride and dutasteride (5-ARIs) have reduced overall prostate cancer risk, while the proportion of high-grade tumors is increased. We studied tumor characteristics, risk of biochemical recurrence and mortality after radical prostatectomy in 5-ARI and alpha-blocker users. METHODS The study cohort consisted of 1,315 men who underwent radical prostatectomy at the Tampere University Hospital during 1995–2009. Biochemical relapse was defined as serum PSA ≥ 0.2 ng/ml after the operation. Information on mortality and medication purchases was obtained from national registries. Cox proportional regression was used to analyze hazard ratios (HRs) and 95% confidence intervals (95% CI) of biochemical relapse and death. RESULTS The proportion of high-grade (Gleason 7–10) tumors was significantly elevated among men who had used 5-ARIs for 4 years or longer compared to the non-users (83.3% vs. 53.3%, respectively). Survival curves for biochemical relapse-free survival differed between long-term and short-term 5-ARI users, but the hazard ratio remained statistically non-significant. Risk of biochemical recurrence was elevated among alpha-blocker users (HR 1.68, 95% CI 1.37–2.06), but in sensitivity analyses this was evident only in men using alpha-blockers after prostatectomy. Mortality was not associated with medication usage. CONCLUSIONS Long-term users of finasteride or dutasteride had more often high-grade prostate cancer. Our results suggest also worse progression-free survival. The association between risk of biochemical recurrence and post-operative alpha-blocker usage suggests that voiding or storage symptoms after prostatectomy may predict biochemical relapse. Prostate 73: 923–931, 2013. © 2013 Wiley Periodicals, Inc.

The authors sought to determine the association between the blunted morning blood pressure (BP) surge and nocturnal BP dipping of the “riser” pattern in 501 patients with hypertension enrolled in the ACHIEVE‐ONE (Ambulatory Blood Pressure Control and Home Blood Pressure [Morning and Evening] Lowering by the N‐Channel Blocker Cilnidipine) trial. The patients' sleep‐trough morning BP surge and prewaking surge were calculated and then classified according to their nocturnal systolic BP reduction pattern as extreme dippers, dippers, nondippers, and risers. The prevalence of the riser pattern was significantly higher in both the lowest sleep‐trough morning BP surge decile and the prewaking surge decile (blunted surge group) compared with the remaining deciles (56.0% vs 10.4% [P

Decreased risk of advanced prostate cancer has been reported among men using statins. However, the evidence on overall prostate cancer risk is conflicting. We compared the relative risk between current users and non-users of statins or other cholesterol-lowering medications in a population undergoing systematical prostate cancer screening. The study cohort comprised of 23,320 men participating in the screening arm of the Finnish prostate cancer screening trial during 1996-2004. Information on medication use was obtained from a comprehensive national prescription database. Cox proportional hazards regression was used to calculate multivariable adjusted hazard ratios (HRs) for prostate cancer. Serum prostate-specific antigen (PSA) level was compared between current users and non-users of cholesterol-lowering drugs. Compared with medication non-users, the overall prostate cancer incidence was decreased among statin users [HR 0.75, 95% confidence interval (CI) 0.63-0.89]. The inverse association was dose-dependent with cumulative amount of statin use, and strongest for low-grade and early stage tumors. The incidence was nonsignificantly lower also among users of other types of cholesterol-lowering drugs (HR 0.62, 95% CI 0.28-1.38), but without dose-dependence. Age-adjusted median serum PSA tended to be lower among users of cholesterol-lowering drugs, but the relative risk decrease among statin users was not related to decreased PSA. Overall incidence of prostate cancer was lowered among statin users when bias due to differential PSA testing between medication users and non-users was eliminated by systematical prostate cancer screening. Cholesterol-lowering with statins seems beneficial for prostate cancer prevention.

Objective Otorrhea and tube occlusion are typical problems with tympanostomy tubes (TT). The purpose of this study was to test glue protein, fibronectin adhesion on albumin-coated and uncoated TT surfaces and to show the effect of this method on TT sequelae in vivo. Study design and settings Fibronectin binding on TT surface was tested in two in vitro experiments. Thereafter 170 patients were randomized in a prospective clinical trial to test the effect of the method in vivo. The extruded TTs that could be collected from ears of some study patients were imaged with scanning electron microscopy (SEM). Results Marked binding inhibition of fibronectin on albumin-coated TTs was found. Fewer tube sequelae were found in ears with albumin-coated TTs. SEM revealed thick crusts on uncoated tube surface. Conclusion Albumin coating of TTs can reduce unwanted adhesion on the tube surface in vitro and tube occlusions in vivo. Significance TT sequelae can be reduced by surface coating with albumin.