Study of the effect of higher-order dispersions on photoionisation induced by ultrafast laser pulses applying a classical theoretical method.

We investigated the effect of higher order dispersion on ultrafast photoionisation with Classical Trajectory Monte Carlo (CTMC) method for hydrogen and krypton atoms. In our calculations we used linearly polarised ultrashort 7 fs laser pulses, [Formula: see text] intensity, and a central wavelength of 800 nm. Our results show that electrons with the highest kinetic energies are obtained with transform limited (TL) pulses. The shaping of the pulses with negative second- third- or fourth- order dispersion results in higher ionisation yield and electron energies compared to pulses shaped with positive dispersion values. We have also investigated how the Carrier Envelope Phase (CEP) dependence of the ionisation is infuenced by dispersion. We calculated the left-right asymmetry as a function of energy and CEP for sodium atoms employing pulses of 4.5 fs, 800 nm central wavelength, and [Formula: see text] intensity. We found that the left-right asymmetry is more pronounced for pulses shaped with positive Group Delay Dispersion (GDD). It was also found that shaping a pulse with increasing amounts of GDD in absolute value blurs the CEP dependence, which is attributed to the increasing number of optical cycles.

Role of core needle biopsy in the treatment of radial scar.

Invasive tumor or ductal carcinoma in situ occur in radial sclerosing lesions in one third of the cases therefore, surgical excision is mandatory. Forty-five patients with radial scar morphology were examined. Ultrasound guided fine-needle aspiration biopsy (FNAB) and core biopsy (CB) were performed in all cases. The postoperative pathological findings were compared to the results of preoperative biopsies. Sensitivity of preoperative percutaneous biopsies (FNAB and CB) was 17.6% and 70.6%, false-negative rate was 82.4% with FNAB and 29.4% with CB. The negative predictive value was 48.1% and 84.8% respectively. Had we done preoperative cytology only, we would have had to perform a two-step procedure (sentinel lymph node biopsy) in 7 patients (15.6%), while with preoperative core biopsy it has decreased to 2 patients (4.4%). Preoperative CB in small radial stellate lesions is recommended to achieve accurate diagnosis in order to avoid a two-step surgical procedures.

Estrogen receptor negative and progesterone receptor positive breast carcinomas-how frequent are they?

Estrogen receptor (ER) testing has become an important part of breast cancer reporting as the ER status is a predictor of hormonal treatment efficacy. Progesteron receptors (PR) are often tested in parallel, and the best response to hormonal manipulations can be expected in tumors positive for both receptors. The existence of breast cancers with an ER negative and PR positive phenotype is controversial. A series of cases with this phenotype were reevaluated to clarify the existence and the frequency of this entity. A total of 205/6587 (3.1%; range of the rate per department: 0.3-7.1%.) cases reported to have the ER-negative and PR-positive status by immunohistochemistry were collected from 9 Hungarian departments. After careful reevaluation of the tumor slides and control tissues with a 1% cut-off for positivity and restaining of the questionable cases, all but 1 of the reevaluable 182 cases changed their original phenotype. Most cases converted to dual positives (n = 124) or dual negatives (n = 31) or unassessable / questionable. ER-negative and PR-positive breast cancers are very rare if existing. Such a phenotype should prompt reassessment.

Sexual dimorphism of kisspeptin and neurokinin B immunoreactive neurons in the infundibular nucleus of aged men and women.

The secretory output of gonadotropin-releasing hormone (GnRH) neurons is critically influenced by peptidergic neurons synthesizing kisspeptins (KP) and neurokinin B (NKB) in the hypothalamic infundibular nucleus (Inf). These cells mediate negative feedback effects of sex steroids on the reproductive axis. While negative feedback is lost in postmenopausal women, it is partly preserved by the sustained testosterone secretion in aged men. We hypothesized that the different reproductive physiology of aged men and women is reflected in morphological differences of KP and NKB neurons. This sexual dimorphism was studied with immunohistochemistry in hypothalamic sections of aged human male (≥50 years) and female (>55 years) subjects. KP and NKB cell bodies of the Inf were larger in females. The number of KP cell bodies, the density of KP fibers, and the incidence of their contacts on GnRH neurons were much higher in aged women compared with men. The number of NKB cell bodies was only slightly higher in women and there was no sexual dimorphism in the regional density of NKB fibers and the incidence of their appositions onto GnRH cells. The incidences of NKB cell bodies, fibers, and appositions onto GnRH neurons exceeded several-fold those of KP-IR elements in men. More NKB than KP inputs to GnRH cells were also present in women. Immunofluorescent studies identified only partial overlap between KP and NKB axons. KP and NKB were colocalized in higher percentages of afferents to GnRH neurons in women compared with men. Most of these sex differences might be explained with the lack of estrogen negative feedback in aged women, whereas testosterone can continue to suppress KP, and to a lesser extent, NKB synthesis in men. Overall, sex differences in reproductive physiology of aged humans were reflected in the dramatic sexual dimorphism of the KP system, with significantly higher incidences of KP-IR neurons, fibers and inputs to GnRH neurons in aged females vs. males.

Triple coincidence experiment to explore the two-electron continuum states of the projectile resulting from mutual ionization in 100-keV He0 + He collisions.

The existence of the two-electron cusp in atomic collisions, i.e., the enhanced emission of two electrons in the forward direction with velocities equal to that of the projectile, has been investigated experimentally. Using a time-of-flight technique, the energies of the two electrons resulting from the simultaneous target and projectile ionization in 100-keV He(0)+He collisions have been measured by detecting triple coincidence between the electrons and the outgoing He(+) ion. The coincidence yield clearly shows a peak as a function of the electron energies at the expected cusp position. Furthermore, a strong correlation was found between the energies of the two electrons, which is traced back to an angular correlation of 180 degrees in the projectile-centered reference system.

TASK-3 immunoreactivity shows differential distribution in the human gastrointestinal tract.

The presence and distribution of TASK-3 immunopositivity (a channel with potential oncogenic significance) was investigated in the human gastrointestinal system. The immunohistochemical reactions were performed with two commercially available polyclonal antibodies, targeting different epitopes of the channel protein. Experiments conducted on frozen and formalin-fixed samples indicated that the application of a suitable antigen retrieval (AR) technique was essential to produce consistent, strong and reproducible TASK-3-specific immunolabelling of the formalin-fixed tissue. The lack of or inappropriate selection of the AR resulted in false-negative reactions. As for the distribution of the TASK-3 channels, strong immunolabelling was observed in the gastric and large intestinal mucosa, with particularly prominent immunoreactivity of the epithelial cells. In contrast, the smooth-muscle layers demonstrated weak TASK-3 positivity. Intense TASK-3 expression was noted in both the exocrine and endocrine pancreas, but the islets of Langerhans exhibited more powerful reactions. The ductal apparatus of the submandibular gland and lymphocytes situated in pericolonic lymph nodes were also TASK-3 positive. Strong TASK-3 positivity could also be observed in malignant gastrointestinal tumours, with intense nuclear-perinuclear labelling of some of the tumour cells. The present findings suggest that TASK-3 channels may have roles in the gastrointestinal functions, including insular hormone secretion.