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Purpose: Limited nutrient transport is hypothesized to be involved in intervertebral disc (IVD) degeneration. It is widely recognized that the dominant mode of transport of small molecules such as glucose is via diffusion, rather than convection. However, recent findings suggest a role for convection-induced by fast (motion-related) and slow (diurnal) dynamic loading in molecular transport of even such small solutes. The aim of this study was to investigate whether fluid exchange induced by simulated physiological loading (composed of both fast cyclic or slower diurnal loading) can influence the molecular transport of a small molecule through the cartilage endplate (CEP) into the nucleus pulposus (NP) of IVDs., Methods: The molecular transport of fluorescein through the CEP and into the NP was studied in a bovine CEP/NP explant model and loading was applied by an axial compression bioreactor. The loaded explants (convection and diffusion) were compared to unloaded explants (diffusion alone)., Results: In the initial 24 h, there were no differences between loaded and unloaded explants, indicating that convection did not enhance molecular transport of small solutes over diffusion alone. Notably, after 48 h which corresponds to two complete diurnal cycles of tissue compression, fluid exudation/imbibing and redistribution, the fluorescein concentration was significantly increased in the top and bottom layer of the explant, when compared to the unloaded explant., Conclusions: Slower diurnal cyclic compression of the IVD might enhance the transport of small molecules into the IVD although it could not be discerned whether this was due to diffusion/convection or a combination., Competing Interests: Declarations. Conflict of interest: The authors declare no conflicts of interest., (© 2024. The Author(s).)

Low back pain is the leading cause of disability worldwide, but current therapeutic interventions are palliative or surgical in nature. Loss of notochordal cells (NCs) and degradation of the healthy matrix in the nucleus pulposus (NP), the central tissue of intervertebral discs (IVDs), has been associated with onset of degenerative disc changes. Recently, we established a protocol for decellularization of notochordal cell derived matrix (NCM) and found that it can provide regenerative cues to nucleus pulposus cells of the IVD. Here, we combined the biologically regenerative properties of decellularized NCM with the mechanical tunability of a poly(ethylene glycol) hydrogel to additionally address biomechanics in the degenerate IVD. We further introduced a hydrolysable PEG-diurethane crosslinker for slow degradation of the gels in vivo. The resulting hydrogels were tunable over a broad range of stiffness's (0.2 to 4.5 kPa), matching that of NC-rich and -poor NP tissues, respectively. Gels formed within 30 min, giving ample time for handling, and remained shear-thinning post-polymerization. Gels also slowly released dNCM over 28 days as measured by GAG effusion. Viability of encapsulated bone marrow stromal cells after extrusion through a needle remained high. Although encapsulated NCs stayed viable over two weeks, their metabolic activity decreased, and their phenotype was lost in physiological medium conditions in vitro. Overall, the obtained gels hold promise for application in degenerated IVDs but require further tuning for combined use with NCs., (© 2023 The Authors. Journal of Biomedical Materials Research Part A published by Wiley Periodicals LLC.)

Current regenerative cartilage therapies are associated with several drawbacks such as dedifferentiation of chondrocytes during expansion and the formation of fibrocartilage. Optimized chondrocyte expansion and tissue formation could lead to better clinical results of these therapies. In this study, a novel chondrocyte suspension expansion protocol that includes the addition of porcine notochordal cell-derived matrix was used to self-assemble human chondrocytes from osteoarthritic (OA) and nondegenerate (ND) origin into cartilage organoids containing collagen type II and proteoglycans. Proliferation rate and viability were similar for OA and ND chondrocytes and organoids formed had a similar histologic appearance and gene expression profile. Organoids were then encapsulated in viscoelastic alginate hydrogels to form larger tissues. Chondrocytes on the outer bounds of the organoids produced a proteoglycan-rich matrix to bridge the space between organoids. In hydrogels containing ND organoids some collagen type I was observed between the organoids. Surrounding the bulk of organoids in the center of the gels, in both OA and ND gels a continuous tissue containing cells, proteoglycans and collagen type II had been produced. No difference was observed in sulphated glycosaminoglycan and hydroxyproline content between gels containing organoids from OA or ND origin after 28 days. It was concluded that OA chondrocytes, which can be harvested from leftover surgery tissue, perform similar to ND chondrocytes in terms of human cartilage organoid formation and matrix production in alginate gels. This opens possibilities for their potential to serve as a platform for cartilage regeneration but also as an in vitro model to study pathways, pathology, or drug development., (© 2023 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals LLC on behalf of Orthopaedic Research Society.)

Porcine notochordal cell-derived matrix (NCM) has anti-inflammatory and regenerative effects on degenerated intervertebral discs. For its clinical use, safety must be assured. The porcine DNA is concerning because of (1) the transmission of endogenous retroviruses and (2) the inflammatory potential of cell-free DNA. Here, we present a simple, detergent-free protocol: tissue lyophilization lyses cells, and matrix integrity is preserved by limiting swelling during decellularization. DNA is digested quickly by a high nuclease concentration, followed by a short washout. Ninety-four percent of DNA was removed, and there was no loss of glycosaminoglycans or collagen. Forty-three percent of the total proteins remained in the decellularized NCM (dNCM). dNCM stimulated as much GAG production as NCM in nucleus pulposus cells but lost some anti-inflammatory effects. Reconstituted pulverized dNCM yielded a soft, shear-thinning biomaterial with a swelling ratio of 350% that also acted as an injectable cell carrier (cell viability >70%). dNCM can therefore be used as the basis for future biomaterials aimed at disc regeneration on a biological level and may restore joint mechanics by creating swelling pressure within the intervertebral disc.

It has been suggested that curvature progression in adolescent idiopathic scoliosis occurs through irreversible changes in the intervertebral discs. Strains of mice have been identified who differ in their disc wedging response upon extended asymmetrical compression. Annulus fibrosus (AF) tissue remodeling could contribute to the faster disc wedging progression previously observed in these mice. Differences in collagen remodeling capacity of AF cells between these in-bred mice strains were compared using an in vitro microtissue system. AF cells of 8-10-week-old LG/J ("fast-healing") and C57BL/6J ("normal healing") mice were embedded in a microtissue platform and cultured for 48 h. Hereafter, tissues were partially released and cultured for another 96 h. Microtissue surface area and waistcoat contraction, collagen orientation, and collagen content were measured. After 96 h postrelease, microtissues with AF cells of LG/J mice showed more surface area contraction (p < .001) and waistcoat contraction (p = .002) than C57BL/6J microtissues. Collagen orientation did not differ at 24 h after partial release. However, at 96 h, collagen in the microtissues from LG/J AF cells was aligned more than in those from C57BL/6J mice (p < .001). Collagen content did not differ between microtissues at 96 h. AF cells of inbred LG/J mice were better able to remodel and realign their collagen fibers than those from C57BL/6J mice. The remodeling of AF tissue could be contributing to the faster disc wedging progression observed in LG/J mice., (© 2020 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals LLC on behalf of Orthopaedic Research Society.)

Purpose: Upon anterior cruciate ligament (ACL) rupture, reconstruction is often required, with the hamstring tendon autograft as most widely used treatment. Post-operative autograft remodeling enhances graft rupture risk, which occurs in up to 10% of the patient population, increasing up to 30% of patients aged under 20 years. Therefore, this research aimed to identify potential biological predictors for graft rupture, derived from patient-specific tissue remodeling-related cell properties in an in vitro micro-tissue platform., Methods: Hamstring tendon-derived cells were obtained from remnant autograft tissue after ACL reconstructions (36 patients, aged 12-55 years), and seeded in collagen I gels on a micro-tissue platform. Micro-tissue compaction over time - induced by altering the boundary constraints - was monitored. Pro-collagen I expression was assessed using ELISA, and protein expression of tenomodulin and α-smooth muscle actin were measured using Western blot. Expression and activity of matrix metalloproteinase 2 were determined using gelatin zymography., Results: Only micro-tissues corresponding to younger patients occasionally released themselves from the constraining posts. Pro-collagen I expression was significantly higher in younger patients. Differences in α-smooth muscle actin and tenomodulin expression between patients were found, but these were age-independent. Active matrix metalloproteinase 2 expression was slightly more abundant in younger patients., Conclusions: The presented micro-tissue platform exposed patient-specific remodeling-related differences between tendon-derived cells, with the micro-tissues that released from constraining posts and pro-collagen I expression best reflecting the clinical age-dependency of graft rupture. These properties can be the starting point in the quest for potential predictors for identifying individual patients at risk for graft rupture.

In situ tissue engineering is a technology in which non-cellular biomaterial scaffolds are implanted in order to induce local regeneration of replaced or damaged tissues. Degradable synthetic electrospun scaffolds are a versatile and promising class of biomaterials for various in situ tissue engineering applications, such as cardiovascular replacements. Functional in situ tissue regeneration depends on the balance between endogenous neo-tissue formation and scaffold degradation. Both these processes are driven by macrophages. Upon invasion into a scaffold, macrophages secrete reactive oxygen species (ROS) and hydrolytic enzymes, contributing to oxidative and enzymatic biomaterial degradation, respectively. This study aims to elucidate the effect of scaffold microarchitecture, i.e., μm-range fiber diameter and fiber alignment, on early macrophage-driven scaffold degradation. Electrospun poly-ε-caprolactone-bisurea (PCL-BU) scaffolds with either 2 or 6 μm (Ø) isotropic or anisotropic fibers were seeded with THP-1 derived human macrophages and cultured in vitro for 4 or 8 days. Our results revealed that macroph age-induced oxidative degradation in particular was dependent on scaffold microarchitecture, with the highest level of ROS-induced lipid peroxidation, NADPH oxidase gene expression and degradation in the 6 μm Ø anisotropic group. Whereas, biochemically polarized macrophages demonstrated a phenotype-specific degradative potential, the observed differences in macrophage degradative potential instigated by the scaffold microarchitecture could not be attributed to either distinct M1 or M2 polarization. This suggests that the scaffold microarchitecture uniquely affects macrophage-driven degradation. These findings emphasize the importance of considering the scaffold microarchitecture in the design of scaffolds for in situ tissue engineering applications and the tailoring of degradation kinetics thereof.

Blood vessel and neurite ingrowth into the degenerating intervertebral disc (IVD) are related to pain. In reported studies, notochordal cell (NC)-conditioned medium (NCCM) induced a regenerative response of nucleus pulposus (NP) cells, but also inhibition of neurite and vessel formation. NC matrix (NCM) derived from NC-rich NP tissue, induced even stronger anabolic effects than NCCM. Thus, the aim was to investigate whether NCM has similar anti-neurogenic and -angiogenic properties as NCCM. NCM and NCCM where produced from porcine NC-rich NP tissue. Human umbilical vein endothelial cells (HUVECs) were cultured in base medium (BM, 300 mOsm), NCCM (produced at 300 and 400 mOsm), NCM, or with chondroitin sulfate (CS, positive control) in angiogenesis-inducing medium, after which vessel length was measured. Although CS alone inhibited vessel growth, NCCM (both osmolarities) stimulated vessel formation by HUVECs. NCM did not affect vessel growth relative to BM. SH-SY5Y cells were cultured in BM, NCCM, and NCM on poly-D-lysine coated and polystyrene surfaces, and analyzed for neurite length and percentage of neurite expressing cells. On coated surfaces, neither NCCM nor NCM affected neurite growth. On a polystyrene surface, NCCM and NCM induced a higher number of neurite-expressing cells. NCCM's previously reported anti-angiogenic and -neurogenic effects were not observed in this study. Although addition of CS inhibited HUVEC vessel formation, other factors may be present in NCCM and NCM that affect neurite and vessel growth. Therefore, future studies testing an NC-based regenerative strategy should carefully assess the risk of such adverse effects in an in vivo setting. © 2018 The Authors. Journal of Orthopaedic Research® Published by Wiley Periodicals, Inc. J Orthop Res 36:3188-3195, 2018., (© 2018 The Authors. Journal of Orthopaedic Research® Published by Wiley Periodicals, Inc.)

During intervertebral disc (IVD) maturation, notochordal cells (NCs) are replaced by chondrocyte-like cells (CLCs) in the nucleus pulposus, suggesting that NCs play a role in maintaining tissue health. Affirmatively, NC-conditioned medium (NCCM) exerts regenerative effects on CLC proliferation and extracellular matrix (ECM) production. The aim of this study was to identify NC-secreted substances that stimulate IVD regeneration. By mass spectrometry of porcine, canine and human NCCM, 149, 170 and 217 proteins were identified, respectively, with 66 proteins in common. Mainly ECM-related proteins were identified, but also organelle-derived and membrane-bound vesicle proteins. To determine whether the effect of NCCM was mediated by soluble and/or pelletable factors, porcine and canine NCCM were separated into a soluble (NCCM-S; peptides and proteins) and pelletable (NCCM-P; protein aggregates and extracellular vesicles) fraction by ultracentrifugation, and tested on bovine and canine CLCs in vitro, respectively. In each model, NCCM-S exerted a more pronounced anabolic effect than NCCM-P. However, glycosaminoglycan (GAG) uptake from the medium into the carrier gel prevented more definite conclusions. While the effect of porcine NCCM-P on bovine CLCs was negligible, canine NCCM-P appeared to enhance GAG and collagen type II deposition by canine CLCs. In conclusion, porcine and canine NCCM exerted their anabolic effects mainly through soluble factors, but also the pelletable NCCM factors showed moderate regenerative potential. Although the regenerative potential of NCCM-P should not be overlooked, future studies should focus on unraveling the protein-based regenerative mechanism from NCCM produced from isolated NCs, e.g. by NCCM fractionation and pathway blocking studies.

Objectives: Notochordal cell-conditioned medium (NCCM) has previously shown to have a stimulatory effect on nucleus pulposus cells (NPCs) and bone marrow stromal cells (BMSCs) in alginate and pellet cultures. These culture methods provide a different environment than the nucleus pulposus (NP) tissue, in which the NCCM ultimately should exert its effect. The objective of this study is to test whether NCCM stimulates NPCs within their native environment, and whether combined stimulation with NCCM and addition of BMSCs has a synergistic effect on extracellular matrix production., Methods: Bovine NP tissue was cultured in an artificial annulus in base medium (BM), porcine NCCM, or BM supplemented with 1 μg/mL Link N. Furthermore, BM and NCCM samples were injected with 10(6) BMSCs per NP sample. Samples were cultured for 4 weeks, and analyzed for biochemical contents (water, glycosaminoglycan [GAG], hydroxyproline, and DNA), gene expression (COL1A1, COL2A1, ACAN, and SOX9), and histology by Safranin O/Fast Green staining., Results: Culture in NCCM resulted in increased proteoglycan content compared to day 0 and BM, similar to Link N. However, only minor differences in gene expression compared to day 0 were observed. Addition of BMSCs did not result in increased GAG content, and surprisingly, DNA content in BMSC-injected groups was not higher than in the other groups after 4 weeks of culture., Discussion: This study shows that, indeed, NCCM is capable of stimulating NPC matrix production within the NP environment. The lack of increased DNA content in the BMSC-injected groups indicates that BMSCs have died over time. Identification of the bioactive factors in NCCM is crucial for further development of an NCCM-based treatment for intervertebral disc regeneration.

Objectives: Conditioned medium derived from notochordal cell-rich nucleus pulposus tissue (NCCM) was previously shown to have a stimulatory effect on bone marrow stromal cells (BMSCs) and nucleus pulposus cells (NPCs) individually, in mixed species in vitro cell models. The objective of the current study was to assess the stimulatory effect of NCCM on NPCs in a homologous canine in vitro model and to investigate whether combined stimulation with NCCM and addition of BMSCs provides a synergistic stimulatory effect., Methods: BMSCs and NPCs were harvested from chondrodystrophic dogs with confirmed early intervertebral disc (IVD) degeneration. NCCM was produced from NP tissue of nonchondrodystrophic dogs with healthy IVDs. BMSCs or NPCs alone (3×10(6) cells/mL) and NPCs+BMSCs (6×10(6) cells/mL; mixed 1:1) were cultured for 4 weeks in 1.2% alginate beads under base medium (BM), NCCM, or with addition of 10 ng/mL transforming growth factor-β1 (TGF-β1) as a positive control. Beads were assessed for glycosaminoglycan (GAG) and DNA contents by biochemical assays, GAG deposition by Alcian blue staining, and gene expression (aggrecan, versican, collagen 1 and 2, SOX9, A disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5), and matrix metalloproteinase 13 [MMP13]) with real-time quantitative RT-PCR., Results: NCCM increased NPC proliferation, proteoglycan production, and expression of genes associated with a healthy NP-like phenotype. BMSCs also showed increased proteoglycan production under NCCM, but these effects were not observed at the gene level. Combined stimulation of NPCs with NCCM and coculturing with BMSCs did not result in increased proteoglycan content compared to stimulation with NCCM alone., Discussion: NCCM stimulates matrix production by both NPCs and BMSCs and directs NPCs toward a healthier phenotype. NCCM is therefore promising for IVD regeneration and identification of the bioactive components will be helpful to further develop this approach. In the current study, no synergistic effect of adding BMSCs was observed.

Recent studies suggest that notochordal cells (NCs) might be involved in intervertebral disc homeostasis, a role exploitable to counteract matrix degradation as observed during degeneration. This study aimed to evaluate the potential of NCs to promote matrix production by nucleus pulposus cells (NPCs) and to compare it to the currently proposed addition of bone marrow stromal cells (BMSCs). Using alginate beads, bovine NPCs were exposed for 28 d to porcine NC conditioned medium (NCCM); direct co-culture with porcine NCs or bovine BMSCs; or the combination of BMSCs and NCCM. Effects on cell proliferation, disc matrix production (proteoglycans, collagens) and disc matrix protein expression (aggrecan, collagen 1 and 2, SOX9) were determined and compared to TGFβ stimulation. NCCM strongly promoted NPC proliferation (x 2.2) and matrix production (x 3.9) to levels similar to that with TGFβ, whereas the direct addition of NCs had no effect. Co-culture of NPCs and BMSCs led to proteoglycan synthesis similar to NPCs alone, which was slightly improved by NCCM (x 1.5). Histological analysis confirmed biochemical data. Gene expression of analysed proteins remained stable for all groups and unaffected by medium conditions. NCs could substantially stimulate NPCs through factors secreted into conditioned medium and in levels similar to the addition of BMSCs. This study showed that molecular agents secreted by NCs constitute a promising alternative to the proposed "standard" injection of BMSCs for disc repair: their effects are similar, do not require the injection of a large number of cells and can be further amplified when the factors are identified.

Heart valve tissue engineering based on decellularized xenogenic or allogenic starter matrices has shown promising first clinical results. However, the availability of healthy homologous donor valves is limited and xenogenic materials are associated with infectious and immunologic risks. To address such limitations, biodegradable synthetic materials have been successfully used for the creation of living autologous tissue-engineered heart valves (TEHVs) in vitro. Since these classical tissue engineering technologies necessitate substantial infrastructure and logistics, we recently introduced decellularized TEHVs (dTEHVs), based on biodegradable synthetic materials and vascular-derived cells, and successfully created a potential off-the-shelf starter matrix for guided tissue regeneration. Here, we investigate the host repopulation capacity of such dTEHVs in a non-human primate model with up to 8 weeks follow-up. After minimally invasive delivery into the orthotopic pulmonary position, dTEHVs revealed mobile and thin leaflets after 8 weeks of follow-up. Furthermore, mild-moderate valvular insufficiency and relative leaflet shortening were detected. However, in comparison to the decellularized human native heart valve control - representing currently used homografts - dTEHVs showed remarkable rapid cellular repopulation. Given this substantial in situ remodeling capacity, these results suggest that human cell-derived bioengineered decellularized materials represent a promising and clinically relevant starter matrix for heart valve tissue engineering. These biomaterials may ultimately overcome the limitations of currently used valve replacements by providing homologous, non-immunogenic, off-the-shelf replacement constructs., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The c.G4883C variant in the leucine-rich repeat kinase 2 (LRRK2) gene (protein effect: Arg1628Pro) has been recently proposed as a second risk factor for sporadic Parkinson's disease in the Han Chinese population (after the Gly2385Arg variant). In this paper, we analyze the Arg1628Pro variant and the associated haplotype in a large sample of 1,337 Han subjects (834 patients and 543 controls) ascertained from a single referral center in Taiwan. In our sample, the Arg1628Pro allele was more frequent among patients (3.8%) than among controls (1.8%; p = 0.004, OR 2.13, 95% CI 1.29-3.52). Sixty heterozygous and two homozygous carriers of the Arg1628Pro variant were identified among the patients, of which only one was also a carrier of the LRRK2 Gly2385Arg variant. We also show that carriers of the Arg1628Pro variant share a common, extended haplotype, suggesting a founder effect. Parkinson's disease onset age was similar in patients who carried the Arg1628Pro variant and in those who did not carry it. Our data support the contention that the Arg1628Pro variant is a second risk factor for Parkinson's disease in the Han Chinese population. Adding the estimated effects of Arg1628Pro (population attributable risk [PAR] approximately 4%) and Gly2385Arg variants (PAR approximately 6%) yields a total PAR of approximately 10%.

Introduction: Despite public opinion and policy interventions, restraint remains a common practice. This is also the case in the Netherlands, where projects aimed to reduce seclusion, have not led to a decreased use of restraint. Is this lack of effectiveness related to attitudes of the professionals? The aim of this study was to explore the attitudes of professionals working in mental health care toward restraint., Method: A questionnaire with eight scales was constructed for measuring attitudes of professionals. Scores of 540 professionals were studied, using analysis of variance and cluster analysis and related to several personnel and organizational characteristics., Results: The more professionals were personally involved in seclusion, the more they believed in it. Three types of professionals were identified: Transformers, Doubters and Maintainers. More than half of the psychiatrists (56%) belonged to the type of maintainers. Nurses were more divided., Conclusion: Professionals working in clinical settings are not really opposed to restraint. This could explain the limited effects of innovation projects.

Mutations in the Leucine-Rich Repeat Kinase 2 (LRRK2) gene are the most frequent known cause of Parkinson's disease (PD), but their prevalence varies markedly between populations. Here we studied the frequency and associated phenotype of four recurrent LRRK2 mutations (R1441C, R1441G, R1441H, and G2019S) in familial and sporadic PD from a single referral center in Lisbon, Portugal. Among 138 unrelated PD probands, we identified 9 heterozygous G2019S carriers (6.52%) and 1 heterozygous R1441H carrier (0.72%). The G2019S mutation was present in 4 of the 107 sporadic (3.74%) and in 5 of the 31 familial probands (16.1%). Mutations were not found among 101 Portuguese controls. The G2019S mutation was present on a single haplotype and displayed reduced penetrance. Heterozygous parkin gene mutations were also found in 2 G2019S-positive probands, but their pathogenic role is unclear. The clinical phenotype in patients with LRRK2 mutations was indistinguishable from that of typical PD, including impaired sense of smell. The G2019S mutation is a very common genetic determinant among the Portuguese patients with PD, and the R1441H mutation is also present in this population. These data have important implications for the diagnostic work-up and genetic counseling of patients with this disease in Portugal.

The Leucine-Rich Repeat Kinase 2 (LRRK2) Gly2019Ser mutation is frequent among Parkinson's disease (PD) patients from the Arab, Jewish, and Iberian populations, while another mutation, Arg1441Gly, is common in the Basque population. We studied the prevalence of these mutations in Sardinia, a Mediterranean genetic isolate with peculiar structure and similarities with the Basque population. Among 98 Sardinian PD probands we detected one heterozygous Gly2019Ser carrier. This mutation was also found in one of 55 Sardinian controls, an 85-year-old man, later shown to have a positive family history of parkinsonism. No carriers of Arg1441Gly, Arg1441Cys, or Arg1441His mutations were found among cases and controls. Our results suggest that the "Basque"LRRK2 mutation is absent or very rare in Sardinia. The Gly2019Ser mutation is present but its frequency is lower than that in Iberian, Arab, or Jewish populations. The identification of an 85-year-old, healthy Gly2019Ser carrier supports the concept that this mutation displays incomplete penetrance.

We analysed the Leucine-Rich Repeat Kinase 2 (LRRK2) gene for the G2019S mutation in 1245 consecutive, unrelated patients with primary degenerative parkinsonism, and collected information on medical history, motor, cognitive and neuropsychiatric functions to characterize the clinical phenotype associated to the G2019S mutation. The mutation was detected in heterozygous state in 19 probands (1.7%), and in five additional affected relatives. Clinical features in carriers were those of typical, idiopathic Parkinson's disease. However, behavioural abnormalities were frequent (87%), suggesting a more widespread limbic involvement in G2019S carriers.

The objective of this study on colorectal cancer was to investigate the associations between SNPs in the genes involved in the arachidonic acid (AA)-pathway, their haplotypes and colorectal cancer. Moreover, interactions between SNPs and fish consumption were considered. In this study, a total of 508 cases and 772 controls were included, originating from 2 prospective cohorts, the Monitoring Project on Cardiovascular Disease Risk Factors (PPHV) and Diagnostisch Onderzoek Mammacarcinoom (DOM). Genotypes of 23 SNPs in 7 candidate genes were determined and the modifying effect of fish consumption was considered. A protective effect of the minor allele of SNP V102V in PTGS2 was observed (odds ratio (OR), 0.37; 95% confidence intervals (CI), 0.16-0.87). The haplotype representing this allele showed a weaker inverse association, indicating that 2 alleles are necessary to obtain this protective effect. Fish consumption data was available for 209 cases and 418 controls. Increased fish consumption was inversely associated with cancer, although not significant (OR, 0.83; 95% CI, 0.57-1.20). Despite the substantial reductions in cancer risk for some genotypes in combination with high fish intake, no significant interactions between any SNP studied and fish consumption were observed. We have previously described an association between colorectal adenomas and SNP V102V in PTGS2 and have now confirmed this association for colorectal adenocarcinomas. Fish consumption of once a week or more might protect against colorectal cancer, but no significant interactions with SNPs in the genes involved in the AA-pathway could be detected within the study., (2006 Wiley-Liss, Inc.)

Mutations in the LRRK2 gene are a cause of autosomal dominant Parkinson's disease (PD). Whether LRRK2 variants influence susceptibility to the commoner, sporadic forms of PD remains largely unknown. Data are particularly limited concerning the Asian population. In search for novel, biologically relevant variants, we sequenced the LRRK2 coding region in Taiwanese patients with PD. Four newly identified variants and another variant recently found in a Taiwanese PD family were tested for association with the disease in a sample of 608 PD cases and 373 ethnically matched controls. Heterozygosity for the Gly2385Arg variant was significantly more frequent among PD patients than controls (nominal p value=0.004, corrected for multiple comparisons=0.012, gender- and age-adjusted odds ratio=2.24, 95% C.I.: 1.29-3.88); this variant was uniformly distributed across genders and age strata. Two novel variants, Met1869Val and Glu1874Stop, were found in one PD case each; their pathogenic role remains, therefore, uncertain. The remaining two novel variants (Ala419Val and Pro755Leu) were present with similar frequency in cases and controls, and were therefore, interpreted as disease-unrelated polymorphisms. Our findings suggest that the LRRK2 Gly2385Arg is the first identified, functionally relevant variant, which acts as common risk factor for sporadic PD in the population of Chinese ethnicity.