^{7}Be(n,α)^{4}He Reaction and the Cosmological Lithium Problem: Measurement of the Cross Section in a Wide Energy Range at n_TOF at CERN

The energy-dependent cross section of the ^{7}Be(n,α)^{4}He reaction, of interest for the so-called cosmological lithium problem in big bang nucleosynthesis, has been measured for the first time from 10 meV to 10 keV neutron energy. The challenges posed by the short half-life of ^{7}Be and by the low reaction cross section have been overcome at n_TOF thanks to an unprecedented combination of the extremely high luminosity and good resolution of the neutron beam in the new experimental area (EAR2) of the n_TOF facility at CERN, the availability of a sufficient amount of chemically pure ^{7}Be, and a specifically designed experimental setup. Coincidences between the two alpha particles have been recorded in two Si-^{7}Be-Si arrays placed directly in the neutron beam. The present results are consistent, at thermal neutron energy, with the only previous measurement performed in the 1960s at a nuclear reactor. The energy dependence reported here clearly indicates the inadequacy of the cross section estimates currently used in BBN calculations. Although new measurements at higher neutron energy may still be needed, the n_TOF results hint at a minor role of this reaction in BBN, leaving the long-standing cosmological lithium problem unsolved.

First Measurement of Several β-Delayed Neutron Emitting Isotopes Beyond N=126

The β-delayed neutron emission probabilities of neutron rich Hg and Tl nuclei have been measured together with β-decay half-lives for 20 isotopes of Au, Hg, Tl, Pb, and Bi in the mass region N≳126. These are the heaviest species where neutron emission has been observed so far. These measurements provide key information to evaluate the performance of nuclear microscopic and phenomenological models in reproducing the high-energy part of the β-decay strength distribution. This provides important constraints on global theoretical models currently used in r-process nucleosynthesis.

Orbital ossifying fibroma: A case report

CLINICAL CASE

The case concerns a 34 year-old man, who presented with pain in the medial canthus in his left eye, with proptosis and diplopia. The examination showed exophthalmus and a palpable mass at the inner canthus. The computed tomography revealed a lesion, which was confirmed by biopsy to be a ossifying fibroma.

DISCUSSION

Ossifying fibroma is a benign fibro-osseous lesion that mostly affects the jaw. Clinical presentation and complications vary according to its location. Clinical examination, imaging, and histopathology are essential for definitive diagnosis. Surgical treatment is multidisciplinary and long-term follow up is needed.

PanGen-Fam: Spanish registry of hereditary pancreatic cancer

PURPOSE

To describe the organisation of the registry and the preliminary results in terms of characteristics of high-risk pancreatic ductal adenocarcinoma (PDAC) families recruited to date and findings of the screening programme. To compare early onset sporadic cases (⩽50 years), sporadic cases (>50 years) and cases with family history of cancer, for PDAC possible risk factors.

METHODS/PATIENTS

Families with hereditary cancer syndromes predisposing to PDAC were recruited from two main sources: Spanish hospitals participating in PanGenEU, a pan-European multicentre case-control study, and their genetic counseling unit. Individuals at high-risk of PDAC were enrolled into a screening programme, consisting of Endoscopic ultrasound, computerised tomography, magnetic resonance imaging. Genetic testing of candidate genes was offered according to each patient's risk.

RESULTS

Among 577 consecutive PDAC cases, recruited via PanGenEU, 36 (6%) had ⩾2 first-degree relative with PDAC: Familial pancreatic cancer (FPC). So far PanGen-Fam has recruited 42 high-risk PDAC families; 25 (60%) had FPC. Five index cases with cancer were positive for BRCA2 and one for BRCA1 germline mutations. In the second year of prospective PDAC screening, one neuroendocrine tumour and a high-grade dysplasia lesion suspicious of carcinoma were diagnosed among 41 high-risk individuals. Furthermore EUS detected chronic-pancreatitis-like parenchymal changes in 15 patients.

CONCLUDING STATEMENT

The identification and recruitment of PDAC high-risk families into the PanGen-Fam registry provides an opportunity to detect early onset cancer and precursor pancreatic cancer lesions at a potentially curative stage and to increase the knowledge of the natural history of the disease.

Nd:YAG laser offers promising treatment option for familial glomuvenous malformation

Although an uncommon entity, familial glomangiomatosis is often a source of significant discomfort to affected patients and impacts quality of life. Patients develop numerous painful vascular lesions, beginning in childhood. Because management strategies for this entity are sparsely reported in the literature, additional study is needed to establish best practice. We report positive results with the use of Nd:YAG laser in treating symptomatic lesions of familial glomuvenous malformation.

Neutron capture cross section of unstable 63Ni: implications for stellar nucleosynthesis

The 63Ni(n,γ) cross section has been measured for the first time at the neutron time-of-flight facility n_TOF at CERN from thermal neutron energies up to 200 keV. In total, capture kernels of 12 (new) resonances were determined. Maxwellian averaged cross sections were calculated for thermal energies from   kT=5-100  keV with uncertainties around 20%. Stellar model calculations for a 25M⊙ star show that the new data have a significant effect on the s-process production of 63Cu, 64Ni, and 64Zn in massive stars, allowing stronger constraints on the Cu yields from explosive nucleosynthesis in the subsequent supernova.

Identification of seven novel SMPD1 mutations causing Niemann-Pick disease types A and B

Niemann-Pick disease (NPD) types A and B are autosomal, recessively inherited, lysosomal storage disorders caused by deficient activity of acid sphingomyelinase (E.C. 3.1.4.12) because of mutations in the sphingomyelin phosphodiesterase-1 (SMPD1) gene. Here, we present the molecular analysis and clinical characteristics of 15 NPD type A and B patients. Sequencing the SMDP1 gene revealed eight previously described mutations and seven novel mutations including four missense [c.682T>C (p.Cys228Arg), c.1159T>C (p.Cys387Arg), c.1474G>A (p.Gly492Ser), and c.1795C>T (p.Leu599Phe)], one frameshift [c.169delG (p.Ala57Leufs*20)] and two splicing (c.316+1G>T and c.1341delG). The most frequent mutations were p.Arg610del (21%) and p.Gly247Ser (12%). Two patients homozygous for p.Arg610del and initially classified as phenotype B showed different clinical manifestations. Patients homozygous for p.Leu599Phe had phenotype B, and those homozygous for c.1341delG or c.316+1G>T presented phenotype A. The present results provide new insight into genotype/phenotype correlations in NPD and emphasize the difficulty of classifying patients into types A and B, supporting the idea of a continuum between these two classic phenotypes.

Time to recanalization and risk of symptomatic intracerebral haemorrhage in patients treated with intravenous thrombolysis

BACKGROUND AND PURPOSE

To test whether time to recanalization is associated with a progressive risk of symptomatic intracerebral haemorrhage (SICH) after intravenous alteplase (IVT), we conducted a serial transcranial duplex monitoring study up to 24 h after IVT in a cohort of 140 patients with acute ischaemic stroke attributed to large artery occlusion in the anterior circulation.

METHODS

Patients were classified in four groups according to the time to complete recanalization (Thrombolysis in Brain Ischaemia, TIBI grades 4 or 5) after alteplase bolus: <2 h (n = 53), 2-6 h (n = 9), 6-24 h (n = 32) and no recanalization (NR) at 24 h (n = 46). SICH was defined as any haemorrhagic transformation with National Institute of Health Stroke Scale (NIHSS) score worsening ≥ 4 points (European Australian Acute Stroke Study II, ECASS II criteria) or parenchymal haematoma type 2 with neurological worsening (SITS-MOST criteria) in the 24-36 h CT. Favourable outcome was defined as modified Rankin score ≤ 2 at 3 months.

RESULTS

There were no differences between the groups of patients who recanalized at each time frame regarding localization of the occlusion (P = 0.29), stroke severity at baseline (P = 0.22) and age (P = 0.06). SICH (ECASS/SITS-MOST) was observed in 5.7%/5.7% of the patients who recanalized in <2 h, in 0%/0% of the patients who recanalized between 2-6 h, in 3.1%/3.1% of the patients who recanalized within 6-24 h and in 2.2%/0% of those patients who did not recanalize at 24 h. The rate of favourable outcome according to the time of recanalization was 79.2%, 50%, 46.9% and 34.1% (P < 0.001).

CONCLUSIONS

Our findings are in line with the literature showing a relationship between time to recanalization and functional outcome after IVT in acute stroke, but they do not confirm a progressive increase in the rate of SICH.