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Severe reaction to radiotherapy provoked by hypomorphic germline mutations in ATM (ataxia–telangiectasia mutated gene)
Background: A minority of breast cancer (BC) patients suffer from severe reaction to adjuvant radiotherapy (RT). Although deficient DNA double-strand break repair is considered the main basis for the reactions, pretreatment identification of high-risk patients has been challenging.
Methods: To retrospectively determine the etiology of severe local reaction to RT in a 39-year-old woman with BC, we performed next-generation sequencing followed by further clinical and functional studies.
Results: We found a −4 intronic variant (c.2251-4A>G) in trans with a synony-mous (c.3576G>A) variant affecting the ATM DNA-repair gene (NG_009830.1, NM_000051.3) which is linked to autosomal recessive ataxia–telangiectasia (A–T). We verified abnormal transcripts resulting from both variants, next to a minor wild-type transcript leading to a residual ATM kinase activity and genomic instability. Follow-up examination of the patient revealed no classic sign of A–T but previously unnoticed head dystonia and mild dysarthria, a family history of BC and late-onset ataxia segregating with the variants. Additionally, her serum level of alpha-fetopro-tein (AFP) was elevated similar to A–T patients.
Conclusion: Considering the variable presentations of A–T and devastating impact of severe reactions to RT, we suggest a routine measurement of AFP in RT-candidate BC patients followed by next-generation sequencing with special attention to non-canonical splice site and synonymous variants in ATM
Severe reaction to radiotherapy provoked by hypomorphic germline mutations in ATM (ataxia–telangiectasia mutated gene)
Background: A minority of breast cancer (BC) patients suffer from severe reaction to adjuvant radiotherapy (RT). Although deficient DNA double-strand break repair is considered the main basis for the reactions, pretreatment identification of high-risk patients has been challenging.
Methods: To retrospectively determine the etiology of severe local reaction to RT in a 39-year-old woman with BC, we performed next-generation sequencing followed by further clinical and functional studies.
Results: We found a −4 intronic variant (c.2251-4A>G) in trans with a synony-mous (c.3576G>A) variant affecting the ATM DNA-repair gene (NG_009830.1, NM_000051.3) which is linked to autosomal recessive ataxia–telangiectasia (A–T). We verified abnormal transcripts resulting from both variants, next to a minor wild-type transcript leading to a residual ATM kinase activity and genomic instability. Follow-up examination of the patient revealed no classic sign of A–T but previously unnoticed head dystonia and mild dysarthria, a family history of BC and late-onset ataxia segregating with the variants. Additionally, her serum level of alpha-fetopro-tein (AFP) was elevated similar to A–T patients.
Conclusion: Considering the variable presentations of A–T and devastating impact of severe reactions to RT, we suggest a routine measurement of AFP in RT-candidate BC patients followed by next-generation sequencing with special attention to non-canonical splice site and synonymous variants in ATM
Prior Stroke in PFO Patients Is Associated With Both PFO-Related and -Unrelated Factors.
Background and Purpose: To identify factors associated with prior stroke at presentation in patients with cryptogenic stroke (CS) and patent foramen ovale (PFO). Methods: We studied cross-sectional data from the International PFO Consortium Study (NCT00859885). Patients with first-ever stroke and those with prior stroke at baseline were analyzed for an association with PFO-related (right-to-left shunt at rest, atrial septal aneurysm, deep venous thrombosis, pulmonary embolism, and Valsalva maneuver) and PFO-unrelated factors (age, gender, BMI, hypertension, diabetes mellitus, hypercholesterolemia, smoking, migraine, coronary artery disease, aortic plaque). A multivariable analysis was used to adjust effect estimation for confounding, e.g., owing to the age-dependent definition of study groups in this cross-sectional study design. Results: We identified 635 patients with first-ever and 53 patients with prior stroke. Age, BMI, hypertension, diabetes mellitus, hypercholesterolemia, coronary artery disease, and right-to-left shunt (RLS) at rest were significantly associated with prior stroke. Using a pre-specified multivariable logistic regression model, age (Odds Ratio 1.06), BMI (OR 1.06), hypercholesterolemia (OR 1.90) and RLS at rest (OR 1.88) were strongly associated with prior stroke.Based on these factors, we developed a nomogram to illustrate the strength of the relation of individual factors to prior stroke. Conclusion: In patients with CS and PFO, the likelihood of prior stroke is associated with both, PFO-related and PFO-unrelated factors
Multi-Jet Event Rates in Deep Inelastic Scattering and Determination of the Strong Coupling Constant
Jet event rates in deep inelastic ep scattering at HERA are investigated
applying the modified JADE jet algorithm. The analysis uses data taken with the
H1 detector in 1994 and 1995. The data are corrected for detector and
hadronization effects and then compared with perturbative QCD predictions using
next-to-leading order calculations. The strong coupling constant alpha_S(M_Z^2)
is determined evaluating the jet event rates. Values of alpha_S(Q^2) are
extracted in four different bins of the negative squared momentum
transfer~\qq in the range from 40 GeV2 to 4000 GeV2. A combined fit of the
renormalization group equation to these several alpha_S(Q^2) values results in
alpha_S(M_Z^2) = 0.117+-0.003(stat)+0.009-0.013(syst)+0.006(jet algorithm).Comment: 17 pages, 4 figures, 3 tables, this version to appear in Eur. Phys.
J.; it replaces first posted hep-ex/9807019 which had incorrect figure 4
Measurement of Leading Proton and Neutron Production in Deep Inelastic Scattering at HERA
Deep--inelastic scattering events with a leading baryon have been detected by
the H1 experiment at HERA using a forward proton spectrometer and a forward
neutron calorimeter. Semi--inclusive cross sections have been measured in the
kinematic region 2 <= Q^2 <= 50 GeV^2, 6.10^-5 <= x <= 6.10^-3 and baryon p_T
<= MeV, for events with a final state proton with energy 580 <= E' <= 740 GeV,
or a neutron with energy E' >= 160 GeV. The measurements are used to test
production models and factorization hypotheses. A Regge model of leading baryon
production which consists of pion, pomeron and secondary reggeon exchanges
gives an acceptable description of both semi-inclusive cross sections in the
region 0.7 <= E'/E_p <= 0.9, where E_p is the proton beam energy. The leading
neutron data are used to estimate for the first time the structure function of
the pion at small Bjorken--x.Comment: 30 pages, 9 figures, 2 tables, submitted to Eur. Phys.
Inhibition of Fibroblast Growth by Notch1 Signaling Is Mediated by Induction of Wnt11-Dependent WISP-1
Fibroblasts are an integral component of stroma and important source of growth factors and extracellular matrix (ECM). They play a prominent role in maintaining tissue homeostasis and in wound healing and tumor growth. Notch signaling regulates biological function in a variety of cells. To elucidate the physiological function of Notch signaling in fibroblasts, we ablated Notch1 in mouse (Notch1Flox/Flox) embryonic fibroblasts (MEFs). Notch1-deficient (Notch1−/−) MEFs displayed faster growth and motility rate compared to Notch1Flox/Flox MEFs. Such phenotypic changes, however, were reversible by reconstitution of Notch1 activation via overexpression of the intracellular domain of Notch1 (NICD1) in Notch1-deficient MEFs. In contrast, constitutive activation of Notch1 signaling by introducing NICD1 into primary human dermal fibroblasts (FF2441), which caused pan-Notch activation, inhibited cell growth and motility, whereas cellular inhibition was relievable when the Notch activation was countered with dominant-negative mutant of Master-mind like 1 (DN-MAML-1). Functionally, “Notch-activated” stromal fibroblasts could inhibit tumor cell growth/invasion. Moreover, Notch activation induced expression of Wnt-induced secreted proteins-1 (WISP-1/CCN4) in FF2441 cells while deletion of Notch1 in MEFs resulted in an opposite effect. Notably, WISP-1 suppressed fibroblast proliferation, and was responsible for mediating Notch1's inhibitory effect since siRNA-mediated blockade of WISP-1 expression could relieve cell growth inhibition. Notch1-induced WISP-1 expression appeared to be Wnt11-dependent, but Wnt1-independent. Blockade of Wnt11 expression resulted in decreased WISP-1 expression and liberated Notch-induced cell growth inhibition. These findings indicated that inhibition of fibroblast proliferation by Notch pathway activation is mediated, at least in part, through regulating Wnt1-independent, but Wnt11-dependent WISP-1 expression
Lung macrophage scavenger receptor SR-A6 (MARCO) is an adenovirus type-specific virus entry receptor
<div><p>Macrophages are a diverse group of phagocytic cells acting in host protection against stress, injury, and pathogens. Here, we show that the scavenger receptor SR-A6 is an entry receptor for human adenoviruses in murine alveolar macrophage-like MPI cells, and important for production of type I interferon. Scavenger receptors contribute to the clearance of endogenous proteins, lipoproteins and pathogens. Knockout of SR-A6 in MPI cells, anti-SR-A6 antibody or the soluble extracellular SR-A6 domain reduced adenovirus type-C5 (HAdV-C5) binding and transduction. Expression of murine SR-A6, and to a lower extent human SR-A6 boosted virion binding to human cells and transduction. Virion clustering by soluble SR-A6 and proximity localization with SR-A6 on MPI cells suggested direct adenovirus interaction with SR-A6. Deletion of the negatively charged hypervariable region 1 (HVR1) of hexon reduced HAdV-C5 binding and transduction, implying that the viral ligand for SR-A6 is hexon. SR-A6 facilitated macrophage entry of HAdV-B35 and HAdV-D26, two important vectors for transduction of hematopoietic cells and human vaccination. The study highlights the importance of scavenger receptors in innate immunity against human viruses.</p></div
Jets and energy flow in photon-proton collisions at HERA
Properties of the hadronic final state in photoproduction events with large transverse energy are studied at the electron-proton collider HERA. Distributions of the transverse energy, jets and underlying event energy are compared to \overline{p}p data and QCD calculations. The comparisons show that the \gamma p events can be consistently described by QCD models including -- in addition to the primary hard scattering process -- interactions between the two beam remnants. The differential jet cross sections d\sigma/dE_T^{jet} and d\sigma/d\eta^{jet} are measured
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