Genome-wide Association Analysis in Humans Links Nucleotide Metabolism to Leukocyte Telomere Length.

Leukocyte telomere length (LTL) is a heritable biomarker of genomic aging. In this study, we perform a genome-wide meta-analysis of LTL by pooling densely genotyped and imputed association results across large-scale European-descent studies including up to 78,592 individuals. We identify 49 genomic regions at a false dicovery rate (FDR) < 0.05 threshold and prioritize genes at 31, with five highlighting nucleotide metabolism as an important regulator of LTL. We report six genome-wide significant loci in or near SENP7, MOB1B, CARMIL1, PRRC2A, TERF2, and RFWD3, and our results support recently identified PARP1, POT1, ATM, and MPHOSPH6 loci. Phenome-wide analyses in >350,000 UK Biobank participants suggest that genetically shorter telomere length increases the risk of hypothyroidism and decreases the risk of thyroid cancer, lymphoma, and a range of proliferative conditions. Our results replicate previously reported associations with increased risk of coronary artery disease and lower risk for multiple cancer types. Our findings substantially expand current knowledge on genes that regulate LTL and their impact on human health and disease.

Leukocyte telomere length, cancer incidence and all-cause mortality among Chinese adults: Singapore Chinese Health Study.

Telomeres play a key role in chromosomal maintenance and stability. To date, few studies have investigated the association of leukocyte telomere length with risk of cancer incidence and all-cause mortality in a large prospective cohort, particularly of the Asian population. Relative telomere lengths in genomic DNA from peripheral blood samples were quantified using a validated quantitative real-time PCR among 26 540 middle-aged or older Chinese adults. Hazard ratios (HRs) and 95% confidence intervals (CIs) of cancer and deaths by quintiles of telomere length were calculated using the Cox proportional hazards regression method with adjustment for age, sex and other potential confounders. After baseline blood collection, 4353 persons developed cancer and 7609 died. Participants with the longest decile of telomeres had a 26% (95% CI: 11%-44%) higher risk of total cancer incidence compared to the shortest decile after controlling for age, sex and other potential founders (Ptrend < .0001). In contrast, longer telomeres were associated with lower risk of all-cause mortality (HR = 0.93; 95% CI: 0.84-1.03), noncancer death (HR = 0.81; 95% CI: 0.71-0.92), specifically, death from chronic obstructive pulmonary disease and pneumonia (HR = 0.79, 95% CI: 0.70-0.89) and digestive diseases (HR = 0.60, 95% CI: 0.42-0.88). Our findings demonstrated that longer telomeres are associated with increased risk of cancer development overall and several common cancer types including breast, rectal, prostate, pancreatic cancer and lung adenocarcinoma. Our study also confirmed that longer telomeres are associated with a reduced risk of noncancer related death.

Measurement of Telomere Length for Longitudinal Analysis: Implications of Assay Precision.

Researchers increasingly wish to test hypotheses concerning the impact of environmental or disease exposures on telomere length (TL), and they use longitudinal study designs to do so. In population studies, TL is usually measured with a quantitative polymerase chain reaction (qPCR)-based method. This method has been validated by calculating its correlation with a gold standard method such as Southern blotting (SB) in cross-sectional data sets. However, in a cross-section, the range of true variation in TL is large, and measurement error is introduced only once. In a longitudinal study, the target variation of interest is small, and measurement error is introduced at both baseline and follow-up. In this paper, we present results from a small data set (n = 20) in which leukocyte TL was measured twice 6.6 years apart by means of both qPCR and SB. The cross-sectional correlations between qPCR and SB were high at both baseline (r = 0.90) and follow-up (r = 0.85), yet their correlation for TL change was poor (r = 0.48). Moreover, the qPCR data but not the SB data showed strong signatures of measurement error. Through simulation, we show that the statistical power gain from performing a longitudinal analysis is much greater for SB than for qPCR. We discuss implications for optimal study design and analysis.

Whole exome sequencing of fetal structural anomalies detected by ultrasonography.

The objective of this study was to evaluate the efficacy of whole exome sequencing (WES) for the genetic diagnosis of cases presenting with fetal structural anomalies detected by ultrasonography. WES was performed on 19 cases with prenatal structural anomalies. Genomic DNA was extracted from umbilical cords or umbilical blood obtained shortly after birth. WES data were analyzed on prenatal phenotypes alone, and the data were re-analyzed after information regarding the postnatal phenotype was obtained. Based solely on the fetal phenotype, pathogenic, or likely pathogenic, single nucleotide variants were identified in 5 of 19 (26.3%) cases. Moreover, we detected trisomy 21 in two cases by WES-based copy number variation analysis. The overall diagnostic rate was 36.8% (7/19). They were all compatible with respective fetal structural anomalies. By referring to postnatal phenotype information, another candidate variant was identified by a postnatal clinical feature that was not detected in prenatal screening. As detailed phenotyping is desirable for better diagnostic rates in WES analysis, we should be aware that fetal phenotype is a useful, but sometimes limited source of information for comprehensive genetic analysis. It is important to amass more data of genotype-phenotype correlations, especially to appropriately assess the validity of WES in prenatal settings.

Impact of olokizumab on platelets, leukocytes and erythrocytes during mild COVID-19.

No abstract present.

Three-dimensional reconstruction of leukocyte internalisation in the luminal uterine epithelium following mating.

Following mating, leukocytes are recruited to the uterine epithelium where they phagocytose spermatozoa and mediate maternal immune tolerance as well as a mild inflammatory response. In this ultrastructural study we utilised array tomography, a high-resolution volume scanning electron microscopy approach to 3D reconstruct the cellular relationships formed by leukocytes recruited to the luminal uterine epithelium 12 h post-mating in the rat. We report that following mating, neutrophils and macrophages are internalised by the luminal uterine epithelium, with multiple leukocytes internalised via contortion through a small tunnel in the apical membrane into a large membrane-bound vacuole within the cytoplasm of luminal uterine epithelial cells (UECs). Once internalised within the UECs, recruited leukocytes appear to phagocytose material within the membrane-bound vacuole and most ultimately undergo a specialised cell death, including vacuolisation and loss of membrane integrity. As these observations involve ultrastructurally normal leukocytic cells internalised within non-phagocytic epithelial cells, these observations are consistent with the formation of cell-in-cell structures via entosis, rather than phagocytic engulfment by UECs. Although cell-in-cell structures have been reported in normal and pathological conditions elsewhere, the data collected herein represents the first evidence of the formation of cell-in-cell structures within the uterine epithelium as a novel component of the maternal inflammatory response to mating.

Telomere shortening velocity of patients administered with hypnotics is accelerated in a gender-differential manner.

The telomere length and its distribution were compared between patients administered with and without hypnotics to see if regular administration of hypnotics is associated with their aging-related somatic telomere shortening. Male patients presented significant shortening of telomere length of circulating leukocytes in association with age (-41.9 bp/year, p = 0.045) in contrast with controls (-18.3 kb/year, p = 0.155). On the other hand, female patients presented no significant shortening of telomere length with aging (-16.4 bp/year, p = 0.372) in contrast with controls (-55.9 bp/year, p = 0.00005). These results suggested that regular administration of hypnotics is associated with aging progression in a gender-related manner. The administration of hypnotics could be an indicator as the somatic aging status and for the screening of background lifestyle-associated diseases promoting biological aging.

MALDI TOF Mass Spectrometry Imaging of Blood Smear: Method Development and Evaluation.

The aim of this study was to develop and evaluate matrix assisted LASER desorption ionization (MALDI) time-of-flight (TOF) mass spectrometry imaging (MSI) of blood smear. Integrated light microscope and MALDI IT-TOF mass spectrometer, together with a matrix sublimation device, were used for analysis of blood smears coming from healthy male donors. Different blood plasma removal, matrix deposition, and instrumental settings were evaluated using the negative and positive ionization modes while agreement between the light microscopy images and the lateral distributions of cellular marker compounds served as the MSI quality indicator. Red and white blood cells chemical composition was analyzed using the differential m/z expression. Five seconds of exposure to ethanol followed by the 5 min of 9-aminoacridine or α-cyano-4-hydroxycinnamic acid deposition, together with two sets of instrumental settings, were selected for the MALDI TOF MSI experiments. Application of the thin and transparent matrix layers assured good correspondence between the LASER footprints and the preselected regions of interest. Cellular marker m/z signals coincided well with the appropriate cells. A metabolite databases search using the differentially expressed m/z produced hits which were consistent with the respective cell types. This study sets the foundations for application of blood smear MALDI TOF MSI in clinical diagnostics and research.

Fibrin and Platelet-Rich Composition in Retrieved Thrombi Hallmarks Stroke With Active Cancer.

BACKGROUND AND PURPOSE: We aim to investigate whether histopathologic examination of thrombi retrieved from acute ischemic stroke patients undergoing endovascular treatment could distinguish cancer-related stroke from other etiologies. METHODS: Thrombi from patients undergoing endovascular treatment were analyzed. The etiology of stroke was divided into cardioembolism, large artery atherosclerosis, and active cancer groups. All selected thrombi were subjected to hematoxylin and eosin staining. The percentages of fibrin/platelets, red blood cells, and white blood cells within a thrombus were quantified. RESULTS: One-hundred fifty-two patients (active cancer, 19; cardioembolism, 107; large artery atherosclerosis, 26) were included. Thrombi from the active cancer group exhibited a higher fibrin/platelet composition than did those from the cardioembolism and large artery atherosclerosis groups (median, 85.7% versus 43.9% and 42.5%; P<0.001). Fibrin/platelet composition was the only independent factor (odds ratio, 1.05 [95% CI, 1.02-1.08]) in differentiating cancer-related stroke from stroke caused by cardioembolism and large artery atherosclerosis. A fibrin/platelet proportion of ≥65% accurately predicted cancer-related stroke (area under the curve, 0.84; P<0.001). CONCLUSIONS: In thrombi retrieved from patients undergoing endovascular treatment, a high fibrin/platelet composition was a probable indicator of cancer-related stroke.

Diagnostic performance of peripheral leukocyte telomere G-tail length for detecting breast cancer.

The telomere G-tail (G-tail) plays an essential role in maintaining chromosome stability. In this study, we assessed the leukocyte G-tail length of breast cancer (BC) patients and cancer-free individuals and evaluated the association between the G-tail length and the presence of BC. A significant shortening of the median G-tail length was observed in BC patients compared with cancer-free individuals and was found in the early phase of BC. Our study indicated that the leukocyte G-tail length might be a potential biomarker for BC detection.

Telomere length dynamics in early life: the blood-and-muscle model.

Telomere length (TL) trajectories in somatic tissues during human growth and development are poorly understood. We examined a blood-and-muscle model during early life, focusing on TL trajectories in leukocytes, representing the highly proliferative hematopoietic system, and skeletal muscle, a minimally proliferative tissue. Leukocyte TL (LTL) and skeletal muscle TL (MTL) were measured in 28 fetuses and 73 children. LTL and MTL were highly variable across individuals (sd: fetal LTL = 0.72 kb, MTL = 0.72 kb; children LTL = 0.81 kb, MTL = 0.82 kb) but were highly correlated within individuals (fetuses, r = 0.76, P < 0.0001; children, r = 0.87, P < 0.0001). LTL was shorter than MTL in fetuses (10.63 vs. 11.01 kb; P = 0.0004) and children (8.46 vs. 9.40 kb; <0.0001). The LTL-MTL gap was smaller in fetuses than children. TL in children was inversely correlated with body mass index (BMI) (LTL: -0.047 ± 0.016 kb/BMI, P < 0.005; MTL: -0.037 ± 0.017 kb/BMI, P = 0.03). We conclude that variations in TL across adults and differences in TL between somatic tissues are largely established in early life. Because TL plays a significant role in aging-related diseases, insight into the factors that fashion TL in somatic tissues during early development should contribute to an understanding of the relationship of TL with these disease and longevity in humans.-Sabharwal, S., Verhulst, S., Guirguis, G., Kark, J. D., Labat, C., Roche, N. E., Martimucci, K., Patel, K., Heller, D. S., Kimura, M., Chuang, D., Chuang, A., Benetos, A., Aviv, A. Telomere length dynamics in early life: the blood-and-muscle model.

Determination of leucocyte extracellular traps (ETs) in seminal fluid (ex vivo) in infertile patients-A pilot study.

Leucocytospermia has been associated with loss of sperm function. Extracellular traps (ETs) of leucocytes are produced during innate immune response. ETs can be activated by spermatozoa in contact with polymorphonuclear (in vitro), inducing sperm entrapment and decrease motility. In this pilot study, we describe the results of ETosis ex vivo, in seminal fluid (SF) smear of infertile patients, associating ETs with leucocytospermia and bacteriospermia. In 21 infertile patients, semen parameters (WHO, 2010), microbiological study, leucocytospermia and presence of ETs in SF were determined. Leucocytes (CD45, CD15 and CD68) were evaluated by immunostaining in SF smears. Indirect immunofluorescence (global histone and H4-citrullinated 3) and scanning electron microscopy (SEM) were used to determine ETs morphology. In 28.6% of patients presented leucocytospermia without bacteriospermia, all of them presented a large number of ETs in the SF smears examined. About 76.6% of the patients without leucocytospermia were positive for ETs. Samples with leucocytospermia have a higher number of ETs and would be related to the amount of leucocytes in the SF. The morphological predominant ETs were diffuse (diffETs) and spread (sprETs). The formation of ETs indicates leucocyte activation in semen, and it was observed that ETosis does not depend exclusively on the presence of bacterial contamination.

Ultrastructural changes in peripheral blood leukocytes in α-synuclein knockout mice.

Effects of α-synuclein deficiency on cellular blood components have not been extensively investigated. This study evaluated ultrastructural changes of leukocytes in α-synuclein knockout (KO) mice using electron microscopy (EM). The following ultrastructural characteristics were quantified in leukocytes: mitochondria, primary granules, specific granules (SG), Golgi apparatus (GA), inclusions, rough-endoplasmic reticulum (RER), smooth-endoplasmic reticulum (SER), and cellular projections (CP). EM showed increased numbers or amounts of SG, inclusions, and SER in KO group (5.3 ±â€¯4.5 in WT vs. 14.1 ±â€¯10.3 in KO, p = 0.02; 0.4 ±â€¯0.9 in WT vs. 3.2 ±â€¯2.8 in KO, p = 0.007; and 7.7 ±â€¯6.7 in WT vs. 17.7 ±â€¯12.2 in KO, p = 0.03, respectively). Although CP number was not significantly different between the two groups (13.4 ±â€¯5.3 in WT vs. 16.3 ±â€¯7.5 in KO, p = 0.32), their size and shapes were altered in KO mice. Notably, findings occurred in the setting of significant lymphopenia. α-Synuclein deficiency leads to changes in size and shape of secretory particles and increases in SER, SG, and inclusions, indicating a potential role for α-synuclein in vesicular trafficking in leukocytes. Further studies are needed to elucidate functions mediated by α-synuclein.

Effects of Pasteurella multocida lipopolysaccharides on bovine leukocytes.

Lipopolysaccharide (LPS) is a major virulence factor of Gram-negative bacteria playing a major role in stimulating protective immune response in mammalian host. However, in many gram-negative bacterial infections, LPS also elicits immunopathology by inducing excessive inflammatory changes. P. multocida (Pm), a gram-negative bacterium, causes acute lung inflammation and fatal septicemic disease in animals. However, the effects of Pm LPS on host cells are little known. In this study, LPS isolated from three different serotypes (B:2, A:1 and A:3) of Pm were individually tested in vitro to assess the response of bovine leukocytes. Pm LPS induced cell proliferation and cell death of leukocytes, in a dose- and time-dependent manner. In these cells, mitochondrial dysfunction and caspase activation mediate cell death.

Application of imaging flow cytometry for characterization of acute inflammation in non-classical animal model systems.

Phagocytes display marked heterogeneity in their capacity to induce and control acute inflammation. This has a significant impact on the effectiveness of antimicrobial immune responses at different tissue sites as well as their predisposition for inflammation-associated pathology. Imaging flow cytometry provides novel opportunities for characterization of these phagocyte populations through high spatial resolution, statistical robustness, and a broad range of quantitative morphometric cell analysis tools. This study highlights an integrative approach that brings together new tools in imaging flow cytometry with conventional methodologies for characterization of phagocyte responses during acute inflammation. We focus on a comparative avian in vivo challenge model to showcase the added depth gained through these novel quantitative multiparametric approaches even in the absence of antibody-based cellular markers. Our characterization of acute inflammation in this model shows significant conservation of phagocytic capacity among avian phagocytes compared to other animal models. However, it also highlights evolutionary divergence with regards to phagocyte inflammation control mechanisms based on the internalization of apoptotic cells.

Alder-Reilly Anomaly in the Cerebrospinal Fluid of a Child With Hurler Syndrome.

Hurler syndrome is an autosomal recessive mucopolysaccharidosis characterized by intralysosomal accumulation of glycosaminoglycan fragments, with cellular accumulation of distended lysosomes resulting in interference with normal cell function. One of the peripheral blood features of mucopolysaccharidoses is the presence of numerous, dark lilac granules within lymphocytes, monocytes, and neutrophils, also known at Alder-Reilly anomaly. Here we describe intracytoplasmic granules with haloes in mononuclear cells present in the cerebrospinal fluid of a 2-year-old boy with the diagnosis of Hurler syndrome, undergoing pretransplant evaluation for an unrelated donor cord blood stem cell transplant.

[Application of the psychological aging scale for healthy people: A preliminary study based on empirical research].

OBJECTIVE: To explore the distribution of psychological aging in healthy population and its relationship with telomere length in peripheral blood leukocyte, and to provide reference for aging evaluation.
 Methods: Stratified random samples were obtained according to age and they were divided into 9 age groups. The age-related psychological information were collected from healthy people by using the self-made scale. Situation of psychological aging, correlation between age and telomere length and score of this scale were analyzed by statistical software.
 Results: A total of 2 100 questionnaires were distributed, and 2 060 of them were valid and has been recovered, with an efficiency of 98.10%. The ratio of male to female was 0.95:1; psychological aging score was in the range of 8.62-23.14; cognitive function score was in the range of 2.25-10.77; emotion score was in the range of 1.45-6.73; personality score was in the range of 0.96-4.22; motivation score was in the range of 1.50-7.18. The correlation coefficient of psychological aging scores with age was 0.721 (P<0.001). The average relative telomere length was 1.06±0.26, and relative telomere length in different age groups were significantly different (F=35.803, P<0.001). Telomere length was negatively correlated with age (r=-0.964, P<0.001) and psychological aging scores (r=-0.915, P=0.004).
 Conclusion: The empirical study of physiological aging scale in healthy population shows that the scores of physical aging are increased with age and that the telomere length is negatively correlated with aging scores, suggesting that the scale can provide reference for the comprehensive evaluation of aging.

Associations of Accelerometer-Measured and Self-Reported Sedentary Time With Leukocyte Telomere Length in Older Women.

Few studies have assessed the association of sedentary time with leukocyte telomere length (LTL). In a cross-sectional study conducted in 2012-2013, we examined associations of accelerometer-measured and self-reported sedentary time with LTL in a sample of 1,481 older white and African-American women from the Women's Health Initiative and determined whether associations varied by level of moderate- to vigorous-intensity physical activity (MVPA). The association between sedentary time and LTL was evaluated using multiple linear regression models. Women were aged 79.2 (standard deviation, 6.7) years, on average. Self-reported sedentary time was not associated with LTL. In a model adjusting for demographic characteristics, lifestyle behaviors, and health-related factors, among women at or below the median level of accelerometer-measured MVPA, those in the highest quartile of accelerometer-measured sedentary time had significantly shorter LTL than those in the lowest quartile, with an average difference of 170 base pairs (95% confidence interval: 4, 340). Accelerometer-measured sedentary time was not associated with LTL in women above the median level of MVPA. Findings suggest that, on the basis of accelerometer measurements, higher sedentary time may be associated with shorter LTL among less physically active women.

Leukocyte Telomere Length and All-Cause, Cardiovascular Disease, and Cancer Mortality: Results From Individual-Participant-Data Meta-Analysis of 2 Large Prospective Cohort Studies.

We studied the associations of leukocyte telomere length (LTL) with all-cause, cardiovascular disease, and cancer mortality in 12,199 adults participating in 2 population-based prospective cohort studies from Europe (ESTHER) and the United States (Nurses' Health Study). Blood samples were collected in 1989-1990 (Nurses' Health Study) and 2000-2002 (ESTHER). LTL was measured by quantitative polymerase chain reaction. We calculated z scores for LTL to standardize LTL measurements across the cohorts. Cox proportional hazards regression models were used to calculate relative mortality according to continuous levels and quintiles of LTL z scores. The hazard ratios obtained from each cohort were subsequently pooled by meta-analysis. Overall, 2,882 deaths were recorded during follow-up (Nurses' Health Study, 1989-2010; ESTHER, 2000-2015). LTL was inversely associated with age in both cohorts. After adjustment for age, a significant inverse trend of LTL with all-cause mortality was observed in both cohorts. In random-effects meta-analysis, age-adjusted hazard ratios for the shortest LTL quintile compared with the longest were 1.23 (95% confidence interval (CI): 1.04, 1.46) for all-cause mortality, 1.29 (95% CI: 0.83, 2.00) for cardiovascular mortality, and 1.10 (95% CI: 0.88, 1.37) for cancer mortality. In this study population with an age range of 43-75 years, we corroborated previous evidence suggesting that LTL predicts all-cause mortality beyond its association with age.

Leukocyte telomere length and renal cell carcinoma survival in two studies.

BACKGROUND: Leukocyte telomere length (LTL) is a potential biomarker of cancer prognosis; however, evidence for renal cell carcinoma (RCC) is inconsistent. METHODS: We investigated LTL and RCC-specific survival among 684 cases from the US kidney cancer study (USKC) and 241 cases from the prostate, lung, colorectal, and ovarian cancer screening trial (PLCO). Leukocyte telomere length was measured by quantitative polymerase chain reaction, and hazard ratios (HRs) and 95% confidence intervals (CIs) computed using multivariable Cox models. RESULTS: Short LTL was associated with poorer disease-specific survival in both USKC (lowest vs highest quartile: HR: 2.3, 95% CI: 1.2-4.4; P for trend=0.02) and PLCO (HR: 2.4, 95% CI: 1.0-5.4; P=0.04). Among USKC cases, the association was strongest for stage-I RCC (HR: 5.5, 95% CI: 1.6-19.0; P=0.006). CONCLUSIONS: Our findings suggest that shorter LTL is an independent marker of poor RCC prognosis, particularly for stage-I disease.