Reply to D. Cummings “Response to: Strong Association Between Birth Month and Reproductive Performance of Vietnamese Women”

Abstract. Background: Suicide is the second leading cause of death among US adolescents aged 12–19 years. Researchers would benefit from a better understanding of the direct effects of bullying and e-bullying on adolescent suicide to inform intervention work. Aims: To explore the direct and indirect effects of bullying and e-bullying on adolescent suicide attempts (SAs) and to estimate the magnitude of these effects controlling for significant covariates. Method: This study uses data from the 2015 Youth Risk Behavior Surveillance Survey (YRBS), a nationally representative sample of US high school youth. We quantified the association between bullying and the likelihood of SA, after adjusting for covariates (i.e., sexual orientation, obesity, sleep, etc.) identified with the PC algorithm. Results: Bullying and e-bullying were significantly associated with SA in logistic regression analyses. Bullying had an estimated average causal effect (ACE) of 2.46%, while e-bullying had an ACE of 4.16%. Limitations: Data are cross-sectional and temporal precedence is not known. Conclusion: These findings highlight the strong association between bullying, e-bullying, and SA.

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Factors Affecting the lnteraction of Tissue Factor/Factor Vll with Factor X in a Heterogeneous Tubular Reactor

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647472 ◽

1991 ◽

Vol 65 (02) ◽

pp. 139-143 ◽

Cited By ~ 7

Author(s):

Cynthia H Gemmell ◽

Vincet T Turitto ◽

Yale Nemerson

Keyword(s):

Steady State ◽

Tissue Factor ◽

Factor Viia ◽

Transmembrane Protein ◽

Strong Association ◽

Tubular Reactor ◽

Factor Xa ◽

Phospholipid Bilayer ◽

Factor Vii ◽

Factor X

SummaryA novel reactor recently described for studying phospholipiddependent blood coagulation reactions under flow conditions similar to those occurring in the vasculature has been further charactenzed. The reactor is a capitlary whose inner wall is coated with a stable phospholipid bilayer (or two bilayers) containing tissue factor, a transmembrane protein that is required for the enzymatic activation of factor X by factor VIIa. Perfusion of the capillary at wall shear rates ranging from 25 s−1 to 1,200 s−1 with purified bovine factors X and VIIa led to steady state factor Xa levels at the outlet. Assay were performed using a chromogenic substrate, SpectrozymeTMFXa, or by using a radiometric technique. In the absence of Ca2+ or factor VIIa there was no product formation. No difference was noted in the levels of factor Xa achieved when non-activated factor VII was perfused. Once steady state was achieved further factor Xa production continued in the absence of factor VIIa implying a very strong association of factor VIIa with the tissue factor in the phospholipid membrane. In agreement with static vesicle-type studies the reactor was sensitive to wall tissue factor concentration, temperature and the presence of phosphatidylserine in the bilayer.

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Factor V Leiden Is Associated with Repeated and Recurrent Unexplained Fetal Losses

Thrombosis and Haemostasis ◽

10.1055/s-0038-1656060 ◽

1997 ◽

Vol 77 (05) ◽

pp. 0822-0824 ◽

Cited By ~ 145

Author(s):

Elvira Grandone ◽

Maurizio Margaglione ◽

Donatella Colaizzo ◽

Marina d'Addedda ◽

Giuseppe Cappucci ◽

...

Keyword(s):

Protein C ◽

Strong Association ◽

Activated Protein C ◽

Fetal Loss ◽

Factor V Leiden ◽

Factor V ◽

Significant Difference ◽

History Of ◽

Fv Leiden ◽

Caucasian Women

SummaryActivated protein C resistance (APCR) is responsible for most cases of familial thrombosis. The factor V missense mutation Arg506>Gln (FV Leiden) has been recognized as the commonest cause of this condition. Recently, it has been suggested that APCR is associated with second trimester fetal loss. We investigated the distribution of FV Leiden in a sample (n = 43) of Caucasian women with a history of two or more unexplained fetal losses. A group (n = 118) of parous women with uneventful pregnancies from the same ethnical background served as control. We found the mutation in 7 cases (16.28%) and 5 controls (4.24%; p = 0.011). A statistically significant difference between women with only early fetal loss vs those with late events (p = 0.04) was observed. Our data demonstrate a strong association between FV Leiden and fetal loss. Furthermore, they indicate that late events are more common in these patients.

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HLA Genotype of Patients with Severe Haemophilia A due to Intron 22 Inversion with and without Inhibitors of Factor VIII

Thrombosis and Haemostasis ◽

10.1055/s-0038-1655945 ◽

1997 ◽

Vol 77 (02) ◽

pp. 238-242 ◽

Cited By ~ 129

Author(s):

J Oldenburg ◽

J K Picard ◽

R Schwaab ◽

H H Brackmann ◽

E G D Tuddenham ◽

...

Keyword(s):

Factor Viii ◽

Major Gene ◽

Statistical Significance ◽

Strong Association ◽

Molecular Genetic ◽

Single Mutation ◽

Severe Haemophilia ◽

Extended Haplotype ◽

Intron 22 Inversion ◽

Hla Genotype

SummaryMolecular genetic studies have shown that development of antibodies to factor VIII (inhibitors) occurs most frequently in patients with severe haemophilia due to major gene lesions including inversions, stop codons and large deletions. Previous studies of HLA type were performed on inhibitor and non-inhibitor patients with diverse uncharacterised mutations which may have confounded detection of significant associations. We therefore selected a group of patients with a single mutation type, the prevalent intron 22 inversion, with or without inhibitors, to determine HLA genotype. Seventy-one such patients, 42 without and 29 with inhibitors (13 high, 9 low and 7 transient responders) were genotyped for MHC Class I HLA-A, -B, -C and Class II HLA-DQA, -DQB and -DRB loci. No strong correlation of any HLA-allele to inhibitor or non-inhibitor status was found. However, alleles of the haplotype HLA-A3, HLA-B7, HLA-C7, HLA-DQA0102, HLA-DQB0602, HLA-DR15 occurred more often in inhibitor patients. Since the alleles of this extended haplotype are common in the North European population only a very strong association would achieve statistical significance. Further studies of groups of patients similar to those studied here will be needed to confirm or exclude this association.

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Mitochondria: the birth place, battle ground and the site of melatonin metabolism in cells

Melatonin Research ◽

10.32794/nr11250011 ◽

2019 ◽

Vol 2 (1) ◽

pp. 44-66 ◽

Cited By ~ 3

Author(s):

Dun-Xian Tan ◽

Russel. J. Reiter

Keyword(s):

Ischemia Reperfusion ◽

Surface Membrane ◽

Strong Association ◽

Membrane Receptors ◽

Melatonin Receptors ◽

Metabolic Enzyme ◽

Intermembrane Space ◽

Antitumor Effects ◽

The Matrix ◽

Surprising Discovery

It was a surprising discovery when mitochondria, as the power houses of cells, were also found to synthesize the potent mitochondrial targeted antioxidant, melatonin. The melatonin synthetic enzyme serotonin N-acetyltransferase (SNAT) was found in matrix and also in the intermembrane space of mitochondria. We hypothesize that the melatonin synthesis occurs in the matrix due to substrate (N-acetyl co-enzyme A) availability while the intermembrane space may serve as the recycling pool of SNAT to regulate the melatonin circadian rhythm. Another surprise was that the melatonin membrane receptors, including MT1 and MT2, were also present in mitochondria. The protective effects of melatonin against neuronal injury induced by brain ischemia/reperfusion were proven to be mainly mediated by mitochondrial melatonin receptors rather than the cell surface membrane receptors which is contrary to the classical principle. In addition, melatonin metabolic enzyme has also been identified in the mitochondria. This enzyme can convert melatonin to N-acetylserotonin to strengthen the antitumor effects of melatonin. Thus, mitochondria are the generator, battle ground and metabolic sites of melatonin. The biological significance of the strong association between mitochondria and melatonin should be intensively investigated.

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