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1.
Immunity ; 56(2): 406-419.e7, 2023 02 14.
Article in English | MEDLINE | ID: mdl-36792574

ABSTRACT

Malaria transmission-blocking vaccines (TBVs) aim to induce antibodies that interrupt malaria parasite development in the mosquito, thereby blocking onward transmission, and provide a much-needed tool for malaria control and elimination. The parasite surface protein Pfs48/45 is a leading TBV candidate. Here, we isolated and characterized a panel of 81 human Pfs48/45-specific monoclonal antibodies (mAbs) from donors naturally exposed to Plasmodium parasites. Genetically diverse mAbs against each of the three domains (D1-D3) of Pfs48/45 were identified. The most potent mAbs targeted D1 and D3 and achieved >80% transmission-reducing activity in standard membrane-feeding assays, at 10 and 2 µg/mL, respectively. Co-crystal structures of D3 in complex with four different mAbs delineated two conserved protective epitopes. Altogether, these Pfs48/45-specific human mAbs provide important insight into protective and non-protective epitopes that can further our understanding of transmission and inform the design of refined malaria transmission-blocking vaccine candidates.


Subject(s)
Culicidae , Malaria Vaccines , Malaria, Falciparum , Malaria , Animals , Humans , Plasmodium falciparum , Culicidae/metabolism , Protozoan Proteins , Antibodies, Monoclonal , Malaria, Falciparum/prevention & control , Antibodies, Protozoan
2.
Am J Hum Genet ; 109(10): 1850-1866, 2022 10 06.
Article in English | MEDLINE | ID: mdl-36150389

ABSTRACT

Infertility affects around 7% of the male population and can be due to severe spermatogenic failure (SPGF), resulting in no or very few sperm in the ejaculate. We initially identified a homozygous frameshift variant in FKBP6 in a man with extreme oligozoospermia. Subsequently, we screened a total of 2,699 men with SPGF and detected rare bi-allelic loss-of-function variants in FKBP6 in five additional persons. All six individuals had no or extremely few sperm in the ejaculate, which were not suitable for medically assisted reproduction. Evaluation of testicular tissue revealed an arrest at the stage of round spermatids. Lack of FKBP6 expression in the testis was confirmed by RT-qPCR and immunofluorescence staining. In mice, Fkbp6 is essential for spermatogenesis and has been described as being involved in piRNA biogenesis and formation of the synaptonemal complex (SC). We did not detect FKBP6 as part of the SC in normal human spermatocytes, but small RNA sequencing revealed that loss of FKBP6 severely impacted piRNA levels, supporting a role for FKBP6 in piRNA biogenesis in humans. In contrast to findings in piRNA-pathway mouse models, we did not detect an increase in LINE-1 expression in men with pathogenic FKBP6 variants. Based on our findings, FKBP6 reaches a "strong" level of evidence for being associated with male infertility according to the ClinGen criteria, making it directly applicable for clinical diagnostics. This will improve patient care by providing a causal diagnosis and will help to predict chances for successful surgical sperm retrieval.


Subject(s)
Azoospermia , Infertility, Male , Animals , Azoospermia/genetics , Humans , Infertility, Male/genetics , Long Interspersed Nucleotide Elements , Male , Mice , RNA, Small Interfering/metabolism , Semen , Spermatogenesis/genetics , Tacrolimus Binding Proteins/genetics , Tacrolimus Binding Proteins/metabolism , Testis/pathology
3.
Small ; 20(9): e2304925, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37857590

ABSTRACT

Manganese is an attractive element for sustainable solutions. It is largely available in the earth's crust, making it ideal for cost-effective and large-scale applications. Especially MnO nanoparticles have recently received attention for applications in battery technology. However, manganese has many oxidation states that are energetically very similar, indicating that they may easily transform from one to the other. Herein, the reversible oxidation of MnO nanoparticles to Mn3 O4 studied with in situ transmission electron microscopy is shown. The oxygen sublattices of MnO and Mn3 O4 are found to be perfectly aligned, and an atomic mechanism where the transformation is facilitated by the migration of Mn cations on the shared O sublattice is proposed. Even when protected with an amorphous carbon layer, MnO particles are highly unstable and oxidize to Mn3 O4 in ethanol. The poor stability of MnO lacks discussion in many battery-related works, and strategies aimed at avoiding this should be developed.

4.
Brain ; 146(9): 3735-3746, 2023 09 01.
Article in English | MEDLINE | ID: mdl-36892415

ABSTRACT

The amyloid cascade hypothesis has strongly impacted the Alzheimer's disease research agenda and clinical trial designs over the past decades, but precisely how amyloid-ß pathology initiates the aggregation of neocortical tau remains unclear. We cannot exclude the possibility of a shared upstream process driving both amyloid-ß and tau in an independent manner instead of there being a causal relationship between amyloid-ß and tau. Here, we tested the premise that if a causal relationship exists, then exposure should be associated with outcome both at the individual level as well as within identical twin-pairs, who are strongly matched on genetic, demographic and shared environmental background. Specifically, we tested associations between longitudinal amyloid-ß PET and cross-sectional tau PET, neurodegeneration and cognitive decline using genetically identical twin-pair difference models, which provide the unique opportunity of ruling out genetic and shared environmental effects as potential confounders in an association. We included 78 cognitively unimpaired identical twins with [18F]flutemetamol (amyloid-ß)-PET, [18F]flortaucipir (tau)-PET, MRI (hippocampal volume) and cognitive data (composite memory). Associations between each modality were tested at the individual level using generalized estimating equation models, and within identical twin-pairs using within-pair difference models. Mediation analyses were performed to test for directionality in the associations as suggested by the amyloid cascade hypothesis. At the individual level, we observed moderate-to-strong associations between amyloid-ß, tau, neurodegeneration and cognition. The within-pair difference models replicated results observed at the individual level with comparably strong effect sizes. Within-pair differences in amyloid-ß were strongly associated with within-pair differences in tau (ß = 0.68, P < 0.001), and moderately associated with within-pair differences in hippocampal volume (ß = -0.37, P = 0.03) and memory functioning (ß = -0.57, P < 0.001). Within-pair differences in tau were moderately associated with within-pair differences in hippocampal volume (ß = -0.53, P < 0.001) and strongly associated with within-pair differences in memory functioning (ß = -0.68, P < 0.001). Mediation analyses showed that of the total twin-difference effect of amyloid-ß on memory functioning, the proportion mediated through pathways including tau and hippocampal volume was 69.9%, which was largely attributable to the pathway leading from amyloid-ß to tau to memory functioning (proportion mediated, 51.6%). Our results indicate that associations between amyloid-ß, tau, neurodegeneration and cognition are unbiased by (genetic) confounding. Furthermore, effects of amyloid-ß on neurodegeneration and cognitive decline were fully mediated by tau. These novel findings in this unique sample of identical twins are compatible with the amyloid cascade hypothesis and thereby provide important new knowledge for clinical trial designs.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Humans , Twins, Monozygotic/genetics , tau Proteins/genetics , tau Proteins/metabolism , Cross-Sectional Studies , Positron-Emission Tomography/methods , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Amyloid/metabolism , Amyloidogenic Proteins , Cognitive Dysfunction/diagnostic imaging , Cognitive Dysfunction/genetics , Cognitive Dysfunction/metabolism , Amyloid beta-Peptides/metabolism
5.
Immunol Rev ; 293(1): 190-215, 2020 01.
Article in English | MEDLINE | ID: mdl-31840844

ABSTRACT

The efficient spread of malaria from infected humans to mosquitoes is a major challenge for malaria elimination initiatives. Gametocytes are the only Plasmodium life stage infectious to mosquitoes. Here, we summarize evidence for naturally acquired anti-gametocyte immunity and the current state of transmission blocking vaccines (TBV). Although gametocytes are intra-erythrocytic when present in infected humans, developing Plasmodium falciparum gametocytes may express proteins on the surface of red blood cells that elicit immune responses in naturally exposed individuals. This immune response may reduce the burden of circulating gametocytes. For both P. falciparum and Plasmodium vivax, there is a solid evidence that antibodies against antigens present on the gametocyte surface, when co-ingested with gametocytes, can influence transmission to mosquitoes. Transmission reducing immunity, reducing the burden of infection in mosquitoes, is a well-acknowledged but poorly quantified phenomenon that forms the basis for the development of TBV. Transmission enhancing immunity, increasing the likelihood or intensity of transmission to mosquitoes, is more speculative in nature but is convincingly demonstrated for P. vivax. With the increased interest in malaria elimination, TBV and monoclonal antibodies have moved to the center stage of malaria vaccine development. Methodologies to prioritize and evaluate products are urgently needed.


Subject(s)
Host-Parasite Interactions/immunology , Malaria, Falciparum/immunology , Malaria, Falciparum/parasitology , Malaria, Vivax/immunology , Malaria, Vivax/parasitology , Plasmodium falciparum/growth & development , Plasmodium falciparum/immunology , Plasmodium vivax/growth & development , Plasmodium vivax/immunology , Antibodies, Blocking/immunology , Antibodies, Protozoan/immunology , Humans , Immunity , Immunomodulation , Life Cycle Stages , Malaria Vaccines/immunology , Malaria, Falciparum/prevention & control , Malaria, Falciparum/transmission , Malaria, Vivax/prevention & control , Malaria, Vivax/transmission
6.
Am J Hum Genet ; 107(2): 342-351, 2020 08 06.
Article in English | MEDLINE | ID: mdl-32673564

ABSTRACT

Male infertility affects ∼7% of men, but its causes remain poorly understood. The most severe form is non-obstructive azoospermia (NOA), which is, in part, caused by an arrest at meiosis. So far, only a few validated disease-associated genes have been reported. To address this gap, we performed whole-exome sequencing in 58 men with unexplained meiotic arrest and identified the same homozygous frameshift variant c.676dup (p.Trp226LeufsTer4) in M1AP, encoding meiosis 1 associated protein, in three unrelated men. This variant most likely results in a truncated protein as shown in vitro by heterologous expression of mutant M1AP. Next, we screened four large cohorts of infertile men and identified three additional individuals carrying homozygous c.676dup and three carrying combinations of this and other likely causal variants in M1AP. Moreover, a homozygous missense variant, c.1166C>T (p.Pro389Leu), segregated with infertility in five men from a consanguineous Turkish family. The common phenotype between all affected men was NOA, but occasionally spermatids and rarely a few spermatozoa in the semen were observed. A similar phenotype has been described for mice with disruption of M1ap. Collectively, these findings demonstrate that mutations in M1AP are a relatively frequent cause of autosomal recessive severe spermatogenic failure and male infertility with strong clinical validity.


Subject(s)
Cell Cycle Checkpoints/genetics , Infertility, Male/genetics , Meiosis/genetics , Mutation/genetics , Proteins/genetics , Spermatogenesis/genetics , Adult , Alleles , Animals , Azoospermia/genetics , Homozygote , Humans , Male , Mice , Phenotype , Spermatozoa/abnormalities , Testis/abnormalities , Turkey , Exome Sequencing/methods
7.
Eur J Nucl Med Mol Imaging ; 50(8): 2409-2419, 2023 07.
Article in English | MEDLINE | ID: mdl-36976303

ABSTRACT

PURPOSE: Tau pathology is associated with concurrent atrophy and decreased cerebral blood flow (CBF) in Alzheimer's disease (AD), but less is known about their temporal relationships. Our aim was therefore to investigate the association of concurrent and longitudinal tau PET with longitudinal changes in atrophy and relative CBF. METHODS: We included 61 individuals from the Amsterdam Dementia Cohort (mean age 65.1 ± 7.5 years, 44% female, 57% amyloid-ß positive [Aß +], 26 cognitively impaired [CI]) who underwent dynamic [18F]flortaucipir PET and structural MRI at baseline and 25 ± 5 months follow-up. In addition, we included 86 individuals (68 CI) who only underwent baseline dynamic [18F]flortaucipir PET and MRI scans to increase power in our statistical models. We obtained [18F]flortaucipir PET binding potential (BPND) and R1 values reflecting tau load and relative CBF, respectively, and computed cortical thickness from the structural MRI scans using FreeSurfer. We assessed the regional associations between i) baseline and ii) annual change in tau PET BPND in Braak I, III/IV, and V/VI regions and cortical thickness or R1 in cortical gray matter regions (spanning the whole brain) over time using linear mixed models with random intercepts adjusted for age, sex, time between baseline and follow-up assessments, and baseline BPND in case of analyses with annual change as determinant. All analyses were performed in Aß- cognitively normal (CN) individuals and Aß+ (CN and CI) individuals separately. RESULTS: In Aß+ individuals, greater baseline Braak III/IV and V/VI tau PET binding was associated with faster cortical thinning in primarily frontotemporal regions. Annual changes in tau PET were not associated with cortical thinning over time in either Aß+ or Aß- individuals. Baseline tau PET was not associated with longitudinal changes in relative CBF, but increases in Braak III/IV tau PET over time were associated with increases in parietal relative CBF over time in Aß + individuals. CONCLUSION: We showed that higher tau load was related to accelerated cortical thinning, but not to decreases in relative CBF. Moreover, tau PET load at baseline was a stronger predictor of cortical thinning than change of tau PET signal.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Humans , Female , Middle Aged , Aged , Male , tau Proteins/metabolism , Cerebral Cortical Thinning , Positron-Emission Tomography , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Atrophy/diagnostic imaging , Cerebrovascular Circulation , Cognitive Dysfunction/metabolism
8.
J Immunol ; 205(4): 945-956, 2020 08 15.
Article in English | MEDLINE | ID: mdl-32641384

ABSTRACT

C-type lectin CLEC16A is located next to CIITA, the master transcription factor of HLA class II (HLA-II), at a susceptibility locus for several autoimmune diseases, including multiple sclerosis (MS). We previously found that CLEC16A promotes the biogenesis of HLA-II peptide-loading compartments (MIICs) in myeloid cells. Given the emerging role of B cells as APCs in these diseases, in this study, we addressed whether and how CLEC16A is involved in the BCR-dependent HLA-II pathway. CLEC16A was coexpressed with surface class II-associated invariant chain peptides (CLIP) in human EBV-positive and not EBV-negative B cell lines. Stable knockdown of CLEC16A in EBV-positive Raji B cells resulted in an upregulation of surface HLA-DR and CD74 (invariant chain), whereas CLIP was slightly but significantly reduced. In addition, IgM-mediated Salmonella uptake was decreased, and MIICs were less clustered in CLEC16A-silenced Raji cells, implying that CLEC16A controls both HLA-DR/CD74 and BCR/Ag processing in MIICs. In primary B cells, CLEC16A was only induced under CLIP-stimulating conditions in vitro and was predominantly expressed in CLIPhigh naive populations. Finally, CLIP-loaded HLA-DR molecules were abnormally enriched, and coregulation with CLEC16A was abolished in blood B cells of patients who rapidly develop MS. These findings demonstrate that CLEC16A participates in the BCR-dependent HLA-II pathway in human B cells and that this regulation is impaired during MS disease onset. The abundance of CLIP already on naive B cells of MS patients may point to a chronically induced stage and a new mechanism underlying B cell-mediated autoimmune diseases such as MS.


Subject(s)
Autoimmunity/immunology , B-Lymphocytes/immunology , Genes, MHC Class II/immunology , Lectins, C-Type/immunology , Monosaccharide Transport Proteins/immunology , Receptors, Antigen, B-Cell/immunology , Antigens, Differentiation, B-Lymphocyte/immunology , Autoimmune Diseases/immunology , Cell Line , Cell Line, Tumor , HLA-DR Antigens/immunology , Histocompatibility Antigens Class II/immunology , Humans , Immunoglobulin M/immunology , Multiple Sclerosis/immunology , Signal Transduction/immunology
9.
Cochrane Database Syst Rev ; 5: CD007411, 2022 05 04.
Article in English | MEDLINE | ID: mdl-35506389

ABSTRACT

BACKGROUND: The inability to have children affects 10% to 15% of couples worldwide. A male factor is estimated to account for up to half of the infertility cases with between 25% to 87% of male subfertility considered to be due to the effect of oxidative stress. Oral supplementation with antioxidants is thought to improve sperm quality by reducing oxidative damage. Antioxidants are widely available and inexpensive when compared to other fertility treatments, however most antioxidants are uncontrolled by regulation and the evidence for their effectiveness is uncertain. We compared the benefits and risks of different antioxidants used for male subfertility. OBJECTIVES: To evaluate the effectiveness and safety of supplementary oral antioxidants in subfertile men. SEARCH METHODS: The Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO, AMED, and two trial registers were searched on 15 February 2021, together with reference checking and contact with experts in the field to identify additional trials. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that compared any type, dose or combination of oral antioxidant supplement with placebo, no treatment, or treatment with another antioxidant, among subfertile men of a couple attending a reproductive clinic. We excluded studies comparing antioxidants with fertility drugs alone and studies that included men with idiopathic infertility and normal semen parameters or fertile men attending a fertility clinic because of female partner infertility. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures recommended by Cochrane. The primary review outcome was live birth. Clinical pregnancy, adverse events and sperm parameters were secondary outcomes. MAIN RESULTS: We included 90 studies with a total population of 10,303 subfertile men, aged between 18 and 65 years, part of a couple who had been referred to a fertility clinic and some of whom were undergoing medically assisted reproduction (MAR). Investigators compared and combined 20 different oral antioxidants. The evidence was of 'low' to 'very low' certainty: the main limitation was that out of the 67 included studies in the meta-analysis only 20 studies reported clinical pregnancy, and of those 12 reported on live birth. The evidence is current up to February 2021. Live birth: antioxidants may lead to increased live birth rates (odds ratio (OR) 1.43, 95% confidence interval (CI) 1.07 to 1.91, P = 0.02, 12 RCTs, 1283 men, I2 = 44%, very low-certainty evidence). Results in the studies contributing to the analysis of live birth rate suggest that if the baseline chance of live birth following placebo or no treatment is assumed to be 16%, the chance following the use of antioxidants is estimated to be between 17% and 27%. However, this result was based on only 246 live births from 1283 couples in 12 small or medium-sized studies. When studies at high risk of bias were removed from the analysis, there was no evidence of increased live birth (Peto OR 1.22, 95% CI 0.85 to 1.75, 827 men, 8 RCTs, P = 0.27, I2 = 32%). Clinical pregnancy rate: antioxidants may lead to increased clinical pregnancy rates (OR 1.89, 95% CI 1.45 to 2.47, P < 0.00001, 20 RCTs, 1706 men, I2 = 3%, low-certainty evidence) compared with placebo or no treatment. This suggests that, in the studies contributing to the analysis of clinical pregnancy, if the baseline chance of clinical pregnancy following placebo or no treatment is assumed to be 15%, the chance following the use of antioxidants is estimated to be between 20% and 30%. This result was based on 327 clinical pregnancies from 1706 couples in 20 small studies. Adverse events Miscarriage: only six studies reported on this outcome and the event rate was very low. No evidence of a difference in miscarriage rate was found between the antioxidant and placebo or no treatment group (OR 1.46, 95% CI 0.75 to 2.83, P = 0.27, 6 RCTs, 664 men, I2 = 35%, very low-certainty evidence). The findings suggest that in a population of subfertile couples, with male factor infertility, with an expected miscarriage rate of 5%, the risk of miscarriage following the use of an antioxidant would be between 4% and 13%. Gastrointestinal: antioxidants may lead to an increase in mild gastrointestinal discomfort when compared with placebo or no treatment (OR 2.70, 95% CI 1.46 to 4.99, P = 0.002, 16 RCTs, 1355 men, I2 = 40%, low-certainty evidence). This suggests that if the chance of gastrointestinal discomfort following placebo or no treatment is assumed to be 2%, the chance following the use of antioxidants is estimated to be between 2% and 7%. However, this result was based on a low event rate of 46 out of 1355 men in 16 small or medium-sized studies, and the certainty of the evidence was rated low and heterogeneity was high. We were unable to draw conclusions from the antioxidant versus antioxidant comparison as insufficient studies compared the same interventions. AUTHORS' CONCLUSIONS: In this review, there is very low-certainty evidence from 12 small or medium-sized randomised controlled trials suggesting that antioxidant supplementation in subfertile males may improve live birth rates for couples attending fertility clinics. Low-certainty evidence suggests that clinical pregnancy rates may increase. There is no evidence of increased risk of miscarriage, however antioxidants may give more mild gastrointestinal discomfort, based on very low-certainty evidence. Subfertile couples should be advised that overall, the current evidence is inconclusive based on serious risk of bias due to poor reporting of methods of randomisation, failure to report on the clinical outcomes live birth rate and clinical pregnancy, often unclear or even high attrition, and also imprecision due to often low event rates and small overall sample sizes. Further large well-designed randomised placebo-controlled trials studying infertile men and reporting on pregnancy and live births are still required to clarify the exact role of antioxidants.


Subject(s)
Abortion, Spontaneous , Infertility, Female , Infertility, Male , Abortion, Spontaneous/epidemiology , Adolescent , Adult , Aged , Antioxidants/adverse effects , Child , Female , Humans , Infertility, Female/drug therapy , Infertility, Male/drug therapy , Infertility, Male/etiology , Live Birth/epidemiology , Male , Middle Aged , Pregnancy , Pregnancy Rate , Young Adult
10.
Geriatr Nurs ; 41(5): 564-570, 2020.
Article in English | MEDLINE | ID: mdl-32238268

ABSTRACT

Continuous information exchange between healthcare professionals is facilitated by individualized care plans. Compliance with the planned care as documented in care plans is important to provide person-centered care which contributes to the continuity of care and quality of care outcomes. Using the Nursing Interventions Classification, this study examined the consistency between documented and actually provided interventions by type of nursing staff with 150 residents in long-term institutional care. The consistency was especially high for basic (93%) and complex (79%) physiological care. To a lesser extent for interventions in the behavioral domain (66%). Except for the safety domain, the probability that documented interventions were provided was high for all domains (≥ 91%, p > 0.05). NAs generally provided the interventions as documented. Findings suggest that HCAs worked beyond there scope of practice. The results may have implications for the deployment of nursing staff and are of importance to managers.


Subject(s)
Health Plan Implementation , Nursing Care/statistics & numerical data , Nursing Homes , Nursing Staff , Patient-Centered Care/standards , Aged, 80 and over , Continuity of Patient Care , Cross-Sectional Studies , Female , Humans , Male
11.
Eur J Immunol ; 48(11): 1861-1871, 2018 11.
Article in English | MEDLINE | ID: mdl-30160778

ABSTRACT

In MS, B cells survive peripheral tolerance checkpoints to mediate local inflammation, but the underlying molecular mechanisms are relatively underexplored. In mice, the MIF pathway controls B-cell development and the induction of EAE. Here, we found that MIF and MIF receptor CD74 are downregulated, while MIF receptor CXCR4 is upregulated in B cells from early onset MS patients. B cells were identified as the main immune subset in blood expressing MIF. Blocking of MIF and CD74 signaling in B cells triggered CXCR4 expression, and vice versa, with separate effects on their proinflammatory activity, proliferation, and sensitivity to Fas-mediated apoptosis. This study reveals a new reciprocal negative regulation loop between CD74 and CXCR4 in human B cells. The disturbance of this loop during MS onset provides further insights into how pathogenic B cells survive peripheral tolerance checkpoints to mediate disease activity in MS.


Subject(s)
B-Lymphocytes/metabolism , Intramolecular Oxidoreductases/metabolism , Macrophage Migration-Inhibitory Factors/metabolism , Multiple Sclerosis/metabolism , Adult , Aged , Antigens, Differentiation, B-Lymphocyte/metabolism , Apoptosis/physiology , Cell Proliferation/physiology , Cell Survival/physiology , Down-Regulation/physiology , Female , Histocompatibility Antigens Class II/metabolism , Humans , Inflammation/metabolism , Male , Middle Aged , Receptors, CXCR4/metabolism , Signal Transduction/physiology , Up-Regulation/physiology , Young Adult
12.
Hum Reprod ; 34(5): 932-941, 2019 05 01.
Article in English | MEDLINE | ID: mdl-30865283

ABSTRACT

STUDY QUESTION: Which genes are confidently linked to human monogenic male infertility? SUMMARY ANSWER: Our systematic literature search and clinical validity assessment reveals that a total of 78 genes are currently confidently linked to 92 human male infertility phenotypes. WHAT IS KNOWN ALREADY: The discovery of novel male infertility genes is rapidly accelerating with the availability of next-generating sequencing methods, but the quality of evidence for gene-disease relationships varies greatly. In order to improve genetic research, diagnostics and counseling, there is a need for an evidence-based overview of the currently known genes. STUDY DESIGN, SIZE, DURATION: We performed a systematic literature search and evidence assessment for all publications in Pubmed until December 2018 covering genetic causes of male infertility and/or defective male genitourinary development. PARTICIPANTS/MATERIALS, SETTING, METHODS: Two independent reviewers conducted the literature search and included papers on the monogenic causes of human male infertility and excluded papers on genetic association or risk factors, karyotype anomalies and/or copy number variations affecting multiple genes. Next, the quality and the extent of all evidence supporting selected genes was weighed by a standardized scoring method and used to determine the clinical validity of each gene-disease relationship as expressed by the following six categories: no evidence, limited, moderate, strong, definitive or unable to classify. MAIN RESULTS AND THE ROLE OF CHANCE: From a total of 23 526 records, we included 1337 publications about monogenic causes of male infertility leading to a list of 521 gene-disease relationships. The clinical validity of these gene-disease relationships varied widely and ranged from definitive (n = 38) to strong (n = 22), moderate (n = 32), limited (n = 93) or no evidence (n = 160). A total of 176 gene-disease relationships could not be classified because our scoring method was not suitable. LARGE SCALE DATA: Not applicable. LIMITATIONS, REASONS FOR CAUTION: Our literature search was limited to Pubmed. WIDER IMPLICATIONS OF THE FINDINGS: The comprehensive overview will aid researchers and clinicians in the field to establish gene lists for diagnostic screening using validated gene-disease criteria and help to identify gaps in our knowledge of male infertility. For future studies, the authors discuss the relevant and important international guidelines regarding research related to gene discovery and provide specific recommendations for the field of male infertility. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by a VICI grant from The Netherlands Organization for Scientific Research (918-15-667 to J.A.V.), the Royal Society, and Wolfson Foundation (WM160091 to J.A.V.) as well as an investigator award in science from the Wellcome Trust (209451 to J.A.V.). PROSPERO REGISTRATION NUMBER: None.


Subject(s)
Genetic Testing/methods , Infertility, Male/genetics , Biomarkers/analysis , DNA Copy Number Variations , DNA Mutational Analysis/methods , DNA Mutational Analysis/statistics & numerical data , Genetic Testing/statistics & numerical data , High-Throughput Nucleotide Sequencing , Humans , Infertility, Male/diagnosis , Male , Reproducibility of Results , Exome Sequencing
13.
Mult Scler ; 25(7): 958-967, 2019 06.
Article in English | MEDLINE | ID: mdl-29774770

ABSTRACT

BACKGROUND: A promising biomarker for axonal damage early in the disease course of multiple sclerosis (MS) is neurofilament light chain (NfL). It is unknown whether NfL has the same predictive value for MS diagnosis in children as in adults. OBJECTIVE: To explore the predictive value of NfL levels in cerebrospinal fluid (CSF) for MS diagnosis in paediatric and adult clinically isolated syndrome (CIS) patients. METHODS: A total of 88 adult and 65 paediatric patients with a first attack of demyelination were included and followed (mean follow up-time in adults: 62.8 months (standard deviation (SD) ±38.7 months) and 43.8 months (SD ±27.1 months) in children). Thirty control patients were also included. Lumbar puncture was done within 6 months after onset of symptoms. NfL was determined in CSF using enzyme-linked immunosorbent assay (ELISA). COX regression analyses were used to calculate hazard ratios (HR) for clinically definite multiple sclerosis (CDMS) diagnosis. RESULTS: After adjustments for age, oligoclonal bands (OCB), and asymptomatic T2 lesions on baseline magnetic resonance imaging (MRI), increased NfL levels in both paediatric and adult CIS patients were associated with a shorter time to CDMS diagnosis (children HR = 3.7; p = 0.007, adults HR = 2.1; p = 0.032). For CIS patients with a future CDMS diagnosis, children showed higher NfL levels than adults (geometric mean 4888 vs 2156 pg/mL; p = 0.007). CONCLUSION: CSF NfL levels are associated with CDMS diagnosis in children and adults with CIS. This makes NfL a promising predictive marker for disease course with potential value in clinical practice.


Subject(s)
Disease Progression , Multiple Sclerosis/cerebrospinal fluid , Multiple Sclerosis/diagnosis , Neurofilament Proteins/cerebrospinal fluid , Adolescent , Adult , Biomarkers/cerebrospinal fluid , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Magnetic Resonance Imaging , Male , Multiple Sclerosis/diagnostic imaging , Multiple Sclerosis/physiopathology
14.
Reprod Biomed Online ; 39(6): 963-968, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31672438

ABSTRACT

RESEARCH QUESTION: Congenital bilateral absence of vas deferens (CBAVD) is characterized by 'obstructive azoospermia' in male patients with primary infertility. In the routine clinical workup of infertile men, patients with an absence of vas deferens are screened for CFTR variants. However, current genetic testing panels do not cover all variants, missing some CBAVD cases. Here, CFTR testing was explored by targeted next-generation sequencing (NGS) to improve variant detection. DESIGN: Five individuals with heterozygous pathogenic CFTR variants were identified using targeted NGS in a cohort of 1112 idiopathic infertile men with azoospermia or severe oligozoospermia. Pre-screening exclusion criteria were CBAVD by clinical examination with positive CFTR sequence analysis as part of routine fertility workup. RESULTS: Cases 1, 2 and 3 presented with CBAVD after which CFTR screening by mutation panel analysis was negative. Case 4 presented with congenital unilateral absence of vas deferens, after which CFTR panel analysis identified a heterozygous p.(Phe508del) variant. Case 5 presented with a palpable vas deferens so CFTR panel analysis was not offered. In all five men, targeted NGS revealed additional pathogenic variants: p.(Arg117Cys) and p.(Arg1158*) (case 1); p.(Asp110His) and p.(Ser945Leu) (case 2); p.(Arg248Thr) and p.(Phe508Cys) (case 3); p.(Gly463Ser) (case 4); p.(Phe508del) (case 4 and 5); and p.(Arg117His) (case 5). CONCLUSIONS: Targeted NGS led to the detection of five infertile men with CFTR variants who would otherwise have remained undiagnosed after routine genetic screening during the fertility workup for azoospermia or severe oligozoospermia. Given the wide availability of affordable targeted NGS, the data suggest that full gene analysis, and not mutation panels, should be considered to screen CFTR in azoospermic men.


Subject(s)
Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Oligospermia/genetics , Adult , High-Throughput Nucleotide Sequencing , Humans , Male , Vas Deferens/abnormalities
15.
Brain ; 141(5): 1334-1349, 2018 05 01.
Article in English | MEDLINE | ID: mdl-29659729

ABSTRACT

Interleukin-17-expressing CD4+ T helper 17 (Th17) cells are considered as critical regulators of multiple sclerosis disease activity. However, depending on the species and pro-inflammatory milieu, Th17 cells are functionally heterogeneous, consisting of subpopulations that differentially produce interleukin-17, interferon-gamma and granulocyte macrophage colony-stimulating factor. In the current study, we studied distinct effector phenotypes of human Th17 cells and their correlation with disease activity in multiple sclerosis patients. T helper memory populations single- and double-positive for C-C chemokine receptor 6 (CCR6) and CXC chemokine receptor 3 (CXCR3) were functionally assessed in blood and/or cerebrospinal fluid from a total of 59 patients with clinically isolated syndrome, 35 untreated patients and 24 natalizumab-treated patients with relapsing-remitting multiple sclerosis, and nine patients with end-stage multiple sclerosis. Within the clinically isolated syndrome group, 23 patients had a second attack within 1 year and 26 patients did not experience subsequent attacks during a follow-up of >5 years. Low frequencies of T helper 1 (Th1)-like Th17 (CCR6+CXCR3+), and not Th17 (CCR6+CXCR3-) effector memory populations in blood strongly associated with a rapid diagnosis of clinically definite multiple sclerosis. In cerebrospinal fluid of clinically isolated syndrome and relapsing-remitting multiple sclerosis patients, Th1-like Th17 effector memory cells were abundant and showed increased production of interferon-gamma and granulocyte macrophage colony-stimulating factor compared to paired CCR6+ and CCR6-CD8+ T cell populations and their blood equivalents after short-term culturing. Their local enrichment was confirmed ex vivo using cerebrospinal fluid and brain single-cell suspensions. Across all pro-inflammatory T helper cells analysed in relapsing-remitting multiple sclerosis blood, Th1-like Th17 subpopulation T helper 17.1 (Th17.1; CCR6+CXCR3+CCR4-) expressed the highest very late antigen-4 levels and selectively accumulated in natalizumab-treated patients who remained free of clinical relapses. This was not found in patients who experienced relapses during natalizumab treatment. The enhanced potential of Th17.1 cells to infiltrate the central nervous system was supported by their predominance in cerebrospinal fluid of early multiple sclerosis patients and their preferential transmigration across human brain endothelial layers. These findings reveal a dominant contribution of Th1-like Th17 subpopulations, in particular Th17.1 cells, to clinical disease activity and provide a strong rationale for more specific and earlier use of T cell-targeted therapy in multiple sclerosis.


Subject(s)
Multiple Sclerosis/immunology , Multiple Sclerosis/pathology , Multiple Sclerosis/therapy , Th17 Cells/physiology , Adult , Brain/pathology , Cell Movement/physiology , Cohort Studies , Cytokines/genetics , Cytokines/metabolism , Female , Flow Cytometry , Humans , Immunologic Factors/therapeutic use , Male , Middle Aged , Multiple Sclerosis/metabolism , Natalizumab/therapeutic use , RNA, Messenger/metabolism , Statistics, Nonparametric , Th17 Cells/drug effects
16.
Cochrane Database Syst Rev ; 3: CD007411, 2019 03 14.
Article in English | MEDLINE | ID: mdl-30866036

ABSTRACT

BACKGROUND: The inability to have children affects 10% to 15% of couples worldwide. A male factor is estimated to account for up to half of the infertility cases with between 25% to 87% of male subfertility considered to be due to the effect of oxidative stress. Oral supplementation with antioxidants is thought to improve sperm quality by reducing oxidative damage. Antioxidants are widely available and inexpensive when compared to other fertility treatments, however most antioxidants are uncontrolled by regulation and the evidence for their effectiveness is uncertain. We compared the benefits and risks of different antioxidants used for male subfertility. This review did not examine the use of antioxidants in normospermic men. OBJECTIVES: To evaluate the effectiveness and safety of supplementary oral antioxidants in subfertile men. SEARCH METHODS: The Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, and two trials registers were searched on 1 February 2018, together with reference checking and contact with study authors and experts in the field to identify additional trials. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that compared any type, dose or combination of oral antioxidant supplement with placebo, no treatment or treatment with another antioxidant, among subfertile men of a couple attending a reproductive clinic. We excluded studies comparing antioxidants with fertility drugs alone and studies that included fertile men attending a fertility clinic because of female partner infertility. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures recommended by Cochrane. The primary review outcome was live birth. Clinical pregnancy, adverse events and sperm parameters were secondary outcomes. MAIN RESULTS: We included 61 studies with a total population of 6264 subfertile men, aged between 18 and 65 years, part of a couple who had been referred to a fertility clinic and some of whom were undergoing assisted reproductive techniques (ART). Investigators compared and combined 18 different oral antioxidants. The evidence was of 'low' to 'very low' quality: the main limitation was that out of the 44 included studies in the meta-analysis only 12 studies reported on live birth or clinical pregnancy. The evidence is current up to February 2018.Live birth: antioxidants may lead to increased live birth rates (OR 1.79, 95% CI 1.20 to 2.67, P = 0.005, 7 RCTs, 750 men, I2 = 40%, low-quality evidence). Results suggest that if in the studies contributing to the analysis of live birth rate, the baseline chance of live birth following placebo or no treatment is assumed to be 12%, the chance following the use of antioxidants is estimated to be between 14% and 26%. However, this result was based on only 124 live births from 750 couples in seven relatively small studies. When studies at high risk of bias were removed from the analysis, there was no evidence of increased live birth (Peto OR 1.38, 95% CI 0.89 to 2.16; participants = 540 men, 5 RCTs, P = 0.15, I2 = 0%).Clinical pregnancy rate: antioxidants may lead to increased clinical pregnancy rates (OR 2.97, 95% CI 1.91 to 4.63, P < 0.0001, 11 RCTs, 786 men, I2 = 0%, low-quality evidence) compared to placebo or no treatment. This suggests that if in the studies contributing to the analysis of clinical pregnancy, the baseline chance of clinical pregnancy following placebo or no treatment is assumed to be 7%, the chance following the use of antioxidants is estimated to be between 12% and 26%. This result was based on 105 clinical pregnancies from 786 couples in 11 small studies.Adverse eventsMiscarriage: only three studies reported on this outcome and the event rate was very low. There was no difference in miscarriage rate between the antioxidant and placebo or no treatment group (OR 1.74, 95% CI 0.40 to 7.60, P = 0.46, 3 RCTs, 247 men, I2 = 0%, very low-quality evidence). The findings suggest that in a population of subfertile men with an expected miscarriage rate of 2%, the chance following the use of an antioxidant would result in the risk of a miscarriage between 1% and 13%.Gastrointestinal: antioxidants may lead to an increase in mild gastrointestinal upsets when compared to placebo or no treatment (OR 2.51, 95% CI 1.25 to 5.03, P = 0.010, 11 RCTs, 948 men, I2 = 50%, very low-quality evidence). This suggests that if the chance of gastrointestinal upsets following placebo or no treatment is assumed to be 2%, the chance following the use of antioxidants is estimated to be between 2% and 9%. However, this result was based on a low event rate of 35 out of 948 men in 10 small or medium-sized studies, and the quality of the evidence was rated very low and was high in heterogeneity.We were unable to draw any conclusions from the antioxidant versus antioxidant comparison as insufficient studies compared the same interventions. AUTHORS' CONCLUSIONS: In this review, there is low-quality evidence from seven small randomised controlled trials suggesting that antioxidant supplementation in subfertile males may improve live birth rates for couples attending fertility clinics. Low-quality evidence suggests that clinical pregnancy rates may also increase. Overall, there is no evidence of increased risk of miscarriage, however antioxidants may give more mild gastrointestinal upsets but the evidence is of very low quality. Subfertilte couples should be advised that overall, the current evidence is inconclusive based on serious risk of bias due to poor reporting of methods of randomisation, failure to report on the clinical outcomes live birth rate and clinical pregnancy, often unclear or even high attrition, and also imprecision due to often low event rates and small overall sample sizes. Further large well-designed randomised placebo-controlled trials reporting on pregnancy and live births are still required to clarify the exact role of antioxidants.


Subject(s)
Antioxidants/therapeutic use , Infertility, Male/drug therapy , Oxidative Stress/drug effects , Abortion, Spontaneous/epidemiology , DNA Damage , DNA Fragmentation , Female , Gastrointestinal Diseases/chemically induced , Humans , Infertility, Male/etiology , Live Birth/epidemiology , Male , Pregnancy , Pregnancy Rate , Randomized Controlled Trials as Topic , Sperm Count , Sperm Motility/drug effects , Spermatozoa/drug effects
17.
Mult Scler ; 24(13): 1715-1724, 2018 11.
Article in English | MEDLINE | ID: mdl-30019626

ABSTRACT

BACKGROUND: Cerebrospinal fluid (CSF) levels of T-cell activation marker soluble CD27 (sCD27) are associated with subsequent disease activity after a first attack of suspected MS in adults. The predictive value for disease course in children with acquired demyelinating syndromes (ADS) is unknown. OBJECTIVES: To assess the predictive value of sCD27 levels for clinically definite multiple sclerosis (CDMS) diagnosis in childhood ADS. METHODS: Children <18 years with a first demyelinating event were prospectively included and followed. Soluble CD27 was determined in CSF using an enzyme-linked immunosorbent assay (ELISA). Cox regression analyses were used to calculate hazard ratios (HRs) for CDMS. RESULTS: A total of 94 ADS children were included (ADS with encephalopathy (ADS+) n = 33 and ADS without encephalopathy (ADS-) n = 61). Of the 61 ADS- children, 21 (48%) were diagnosed with CDMS during follow-up. At baseline, sCD27 levels were higher in patients with a future CDMS diagnosis ( n = 29) than in monophasic ADS+ ( n = 30), monophasic ADS- ( n = 28) and relapsing non-MS patients ( n = 7; p < 0.001). In ADS- patients, sCD27 was associated with CDMS (HR = 1.8 per 100 U/mL increase in sCD27 levels, p = 0.031), after adjustments for age, oligoclonal bands and the presence of dissemination in space on baseline magnetic resonance imaging (MRI). CONCLUSION: CSF sCD27 levels at first attack of demyelination were associated with CDMS diagnosis in children. This makes sCD27 a potential clinically relevant quantitative marker when performing routine CSF diagnostics.


Subject(s)
Demyelinating Diseases/immunology , Multiple Sclerosis/immunology , T-Lymphocytes/immunology , Tumor Necrosis Factor Receptor Superfamily, Member 7/metabolism , Disease Progression , Humans , Magnetic Resonance Imaging/methods , Multiple Sclerosis/diagnosis , Prospective Studies , Spinal Cord/immunology , Syndrome
18.
Mult Scler ; 24(7): 974-981, 2018 06.
Article in English | MEDLINE | ID: mdl-28532229

ABSTRACT

BACKGROUND: Fatigue is reported by more than 75% of multiple sclerosis (MS) patients. In an earlier study, we showed that fatigue is not only a common symptom in patients at time of clinically isolated syndrome (CIS; fatigued 46%) but also predicts subsequent diagnosis of clinically definite multiple sclerosis (CDMS). The course of fatigue after CIS is unknown. OBJECTIVE: We aimed to explore the long-term course of fatigue after CIS. METHODS: In this study, 235 CIS patients, aged 18-50 years, were prospectively followed. Patients filled in the Krupp's Fatigue Severity Scale (FSS) and the Hospital Anxiety and Depression Scale (HADS) at baseline and annually. After reaching CDMS diagnosis, Expanded Disability Status Scale (EDSS) was obtained annually. Mixed-effects models were used to analyse longitudinal FSS measurements. RESULTS: Fatigue at baseline was an independent predictor for CDMS diagnosis (hazard ratio (HR): 2.6, 95% confidence interval (CI): 1.6-4.4). The evolution of FSS was the same in CIS patients who remained monophasic and patients who were diagnosed with CDMS during follow-up. However, FSS increased by 0.86 units after reaching CDMS diagnosis ( p = 0.01). After this increase, the FSS course remained unaltered ( p = 0.44). CONCLUSION: Fatigue, which is often present at time of CIS, probably persists over time and increases after a second attack.


Subject(s)
Demyelinating Diseases/complications , Fatigue/epidemiology , Fatigue/etiology , Multiple Sclerosis/complications , Adult , Disability Evaluation , Disease Progression , Female , Humans , Longitudinal Studies , Male , Middle Aged , Prospective Studies
19.
Ann Surg Oncol ; 23(2): 477-81, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26369528

ABSTRACT

BACKGROUND: The usefulness of axillary lymph node dissection (ALND) in patients with positive sentinel nodes (SN) is still an ongoing debate. Several nomograms have been developed for predicting non-sentinel lymph node metastases (NSLNM). We validated six nomograms using data from 10 years of breast cancer surgery in our hospital. METHODS: We retrospectively analyzed all patients with a proven breast malignancy and a SN procedure between 2001 and 2011 in our hospital. RESULTS: Data from 1084 patients were reviewed; 260 (24 %) had a positive SN. No patients with isolated tumor cells, 6 patients (8 %) with micrometastases, and 65 patients (41 %) with macrometastases had additional axillary NSLNM. In 2 patients (3 %) with micrometastases, the ALND influenced postoperative treatment. In the group of patients with macrometastases tumor size >2 cm, extranodal growth and having no negative SNs were predictors of NSLNM. The revised MD Anderson Cancer Center and Helsinki nomograms performed the best, with an area under the curve value of 0.78. CONCLUSIONS: ALND could probably be safely omitted in most patients with micrometastases but is still indicated in patients with macrometastases, especially in patients with tumor size >2 cm, extranodal growth, and no negative SNs. The revised MD Anderson Cancer Center and Helsinki nomograms were the most predictive in our patient group.


Subject(s)
Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/secondary , Carcinoma, Lobular/secondary , Models, Statistical , Nomograms , Adult , Aged , Aged, 80 and over , Area Under Curve , Breast Neoplasms/metabolism , Breast Neoplasms/surgery , Carcinoma, Ductal, Breast/metabolism , Carcinoma, Ductal, Breast/surgery , Carcinoma, Lobular/metabolism , Carcinoma, Lobular/surgery , Female , Follow-Up Studies , Humans , Lymph Node Excision , Lymphatic Metastasis , Middle Aged , Neoplasm Invasiveness , Neoplasm Staging , Prognosis , Receptor, ErbB-2/metabolism , Receptors, Estrogen/metabolism , Receptors, Progesterone/metabolism , Retrospective Studies , Sentinel Lymph Node Biopsy
20.
Phys Chem Chem Phys ; 18(27): 18006-14, 2016 Jul 21.
Article in English | MEDLINE | ID: mdl-27326536

ABSTRACT

The effect of high concentration, also referred to as crowding conditions, on Brownian motion is of central relevance for the understanding of the physical, chemical and biological properties of proteins in their native environment. Specifically, the simple inverse relationship between the translational diffusion coefficient and the macroscopic solution viscosity as predicted by the generalized Stokes-Einstein (GSE) relation has been the subject of many studies, yet a consensus on its applicability has not been reached. Here, we use isotope-filtered pulsed-field gradient NMR to separately assess the µm-scale diffusivity of two proteins, BSA and an SH3 domain, in mixtures as well as single-protein solutions, and demonstrate that transient binding can account for an apparent violation of the GSE relation. Whereas GSE behavior applies for the single-protein solutions, it does not hold for the protein mixtures. Transient binding behavior in the concentrated mixtures is evidenced by calorimetric experiments and by a significantly increased apparent activation energy of diffusion. In contrast, the temperature dependence of the viscosity, as well as of the diffusivity in single-component solutions, is always dominated by the flow activation energy of pure water. As a practically relevant second result, we further show that, for high protein concentrations, the diffusion of small molecules such as dioxane or water is not generally a suitable probe for the viscosity experienced by the diffusing proteins.


Subject(s)
Proteins/chemistry , Solutions/chemistry , Biophysical Phenomena , Diffusion , Magnetic Resonance Spectroscopy , Proteins/metabolism , Rotation , Temperature , Viscosity , Water
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