Publications by authors named "Lauri Heiskanen"

6 Publications

  • Page 1 of 1

Depression and Nigral Neuron Density in Lewy Body Spectrum Diseases.

Ann Neurol 2021 Feb 9. Epub 2021 Feb 9.

Clinical Neurosciences, University of Turku, Turku, Finland.

Parkinson's disease and other Lewy body spectrum diseases (LBDs) are associated with a specific risk for clinical depression. In the present clinicopathological study with 73 patients with LBD, we observed that the substantia nigra pars compacta dopamine neuron density was markedly lower in patients who had comorbid depression antemortem than in nondepressed patients (1.52 vs 2.32 n/mm , p = 0.004). There were no differences in cognition, motor disease severity, antiparkinsonian medications, or disease duration between groups. The results implicate the substantia nigra as an important psychomotor modulatory area of mood in patients with Lewy body disorders. ANN NEUROL 2021.
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February 2021

Insect herbivory dampens Subarctic birch forest C sink response to warming.

Nat Commun 2020 05 21;11(1):2529. Epub 2020 May 21.

Faculty of Biological and Environmental Sciences, University of Helsinki, Niemenkatu 73, 15140, Lahti, Finland.

Climate warming is anticipated to make high latitude ecosystems stronger C sinks through increasing plant production. This effect might, however, be dampened by insect herbivores whose damage to plants at their background, non-outbreak densities may more than double under climate warming. Here, using an open-air warming experiment among Subarctic birch forest field layer vegetation, supplemented with birch plantlets, we show that a 2.3 °C air and 1.2 °C soil temperature increase can advance the growing season by 1-4 days, enhance soil N availability, leaf chlorophyll concentrations and plant growth up to 400%, 160% and 50% respectively, and lead up to 122% greater ecosystem CO uptake potential. However, comparable positive effects are also found when insect herbivory is reduced, and the effect of warming on C sink potential is intensified under reduced herbivory. Our results confirm the expected warming-induced increase in high latitude plant growth and CO uptake, but also reveal that herbivorous insects may significantly dampen the strengthening of the CO sink under climate warming.
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May 2020

Both comorbidity and worse performance status are associated with poorer overall survival after external beam radiotherapy for prostate cancer.

BMC Cancer 2020 Apr 15;20(1):324. Epub 2020 Apr 15.

Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland.

Background: In this retrospective study, we evaluated the biochemical recurrence rate, metastatic disease progression, and prostate cancer-specific and overall survival in patients curatively treated with external beam radiotherapy (EBRT) for early prostate cancer (PC). We also examined the prognostic effect of comorbidity by Charlson Comorbidity Index (CCI) and overall performance status by Eastern Clinical Oncology Group (ECOG) score.

Methods: A total of 665 men treated between 2008 and 2013 were enrolled from Tampere University Hospital, Finland. Prostate-specific antigen (PSA) tests and hospital records were used to determine the 5-year survival for each aforementioned endpoint using a Kaplan-Meyer estimate. To analyze the impact of the selected prognostic factor, we used a Cox regression model to calculate the corresponding hazard ratio (HR) and 95% confidence interval (CI).

Results: With a median follow-up-time of 7.12 years, the 5-year overall survival (OS) after EBRT was 88.9% [86.5 -91.3%], prostate cancer-specific survival (PCSS) was 97.9% [96.7 -99.1%], metastasis-free survival (MFS) 94.8% [93.0 -96.6%] and biochemical recurrence-free survival (BRFS) 88.7% [86.2 -91.2%]. Both CCI (HR = 1.38, [1.25-1.51]) and ECOG score (HR = 1.63, [1.29-2.05]) declined OS, as well as Gleason score and T score (P <  0.05). Gleason score and T grade also associated to worse PCSS, MFS and BRFS.

Conclusions: CCI and ECOG score are useful tools in evaluating the overall life expectancy of the patient after EBRT for PC. T-stage and Gleason score remain still the major prognostic factors.
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April 2020

Diffusion parameters of the core of cingulum are associated with age-related ventricular enlargement: a diffusion tensor tractography study.

Neuroradiology 2018 Oct 8;60(10):1013-1018. Epub 2018 Aug 8.

Department of Neurology, University of Turku, 20014, Turku, Finland.

Purpose: To evaluate the influence of the size of lateral ventricles on diffusion parameters of the normal cingulate bundle.

Methods: Eighty normal subjects (17-55 years) underwent MRI at 3 T including diffusion tensor imaging. Superior (SC) and inferior (IC) cingulum were analyzed separately. Mean diffusivity (MD) and fractional anisotropy (FA) were measured by tractography at FA threshold 0.30; further diffusion parameters were analyzed by tractography-based core analysis in volumes of 3.0 cm/1.5 cm. The diffusion parameters were correlated with corresponding cross-sectional coronal areas of lateral ventricles. The analysis was performed also separately for young (17-34) and middle-aged (35-55) subjects.

Results: FA values did not correlate with ventricular size, but there was a weak negative correlation (r = - 0.225) between MD of SC and ventricular size. In all controls and in the older age group, ventricular size correlated positively with core FA of SC (r = 0.262/r = 0.391) and negatively with mean diffusivity (r = - 0.324/r = - 0.303) and radial diffusivity (λ: r = - 0.238/r = - 0.277; λ: r = - 0.353/r = - 0.424) of the core of SC. In the younger age group, only the mean diffusivity of SC correlated with ventricular size (r = - 0.273). Ventricular size was not associated with axial diffusivity. The core parameters of IC did not correlate with ventricular size.

Conclusion: Radial diffusivity of the core of cingulum decreases in age-dependent ventricular enlargement, which can be related to tissue compaction with stretching of axons and diminution of extracellular spaces. The phenomenon, which is reverse to the assumed effect of age-related myelin loss, can influence on DTI parameters in middle-aged subjects.
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October 2018

Season of death and nigral neuronal density in a high-latitude region.

Neuropathol Appl Neurobiol 2019 04 21;45(3):314-317. Epub 2018 May 21.

Department of Neurology, University of Turku, Turku, Finland.

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April 2019

Cranioplasty After Severe Traumatic Brain Injury: Effects of Trauma and Patient Recovery on Cranioplasty Outcome.

Front Neurol 2018 9;9:223. Epub 2018 Apr 9.

Department of Biomaterials Science and Turku Clinical Biomaterials Centre--TCBC, Institute of Dentistry, University of Turku, Turku, Finland.

Background: In patients with severe traumatic brain injury (sTBI) treated with decompressive craniectomy (DC), factors affecting the success of later cranioplasty are poorly known.

Objective: We sought to investigate if injury- and treatment-related factors, and state of recovery could predict the risk of major complications in cranioplasty requiring implant removal, and how these complications affect the outcome.

Methods: A retrospective cohort of 40 patients with DC following sTBI and subsequent cranioplasty was studied. Non-injury-related factors were compared with a reference population of 115 patients with DC due to other conditions.

Results: Outcome assessed 1 day before cranioplasty did not predict major complications leading to implant removal. Successful cranioplasty was associated with better outcome, whereas a major complication attenuates patient recovery: in patients with favorable outcome assessed 1 year after cranioplasty, major complication rate was 7%, while in patients with unfavorable outcome the rate was 42% ( = 0.003). Of patients with traumatic subarachnoid hemorrhage (tSAH) on admission imaging 30% developed a major complication, while none of patients without tSAH had a major complication ( = 0.014). Other imaging findings, age, admission Glasgow Coma Scale, extracranial injuries, length of stay at intensive care unit, cranioplasty materials, and timing of cranioplasty were not associated with major complications.

Conclusion: A successful cranioplasty after sTBI and DC predicts favorable outcome 1 year after cranioplasty, while stage of recovery before cranioplasty does not predict cranioplasty success or failure. tSAH on admission imaging is a major risk factor for a major complication leading to implant removal.
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April 2018