High accuracy alignment facility for the receiver and transmitter of the BepiColombo Laser Altimeter

The accurate co-alignment of the transmitter to the receiver of the BepiColombo Laser Altimeter is a challenging task for which an original alignment concept had to be developed. We present here the design, construction and testing of a large collimator facility built to fulfill the tight alignment requirements. We describe in detail the solution found to attenuate the high energy of the instrument laser transmitter by an original beam splitting pentaprism group. We list the different steps of the calibration of the alignment facility and estimate the errors made at each of these steps. We finally prove that the current facility is ready for the alignment of the flight instrument. Its angular accuracy is 23 μrad.

Papillary glioneuronal tumor

The descriptive term papillary glioneuronal tumor (PGNT) has been repeatedly applied to a morphologic subset of low-grade mixed glial-neuronal neoplasia of juvenile and young adult patients. We report on a 13-year-old boy with PGNT of the left temporal lobe, who presented with headaches and a single generalized seizure. On magnetic resonance imaging, tumor was seen as a large, moderately enhancing paraventricular mass with cyst-mural nodule configuration and slight midline shift. Perifocal edema was virtually absent. Gross total resection could be performed, followed by an uneventful recovery. Histologically, the tumor exhibited similar, if not identical, features as reported previously. These comprised a patterned biphasic mixture of sheets of synaptophysin-expressing small round cells and pseudorosettes of GFAP-positive rudimentary astrocytes along vascular cores. Focally, the latter imprinted a pseudopapillary aspect on this otherwise solid lesion. Both cellular components expressed non-polysialylated neural cell adhesion molecule (NCAM)-L species, and several overlapping areas of synaptophysin and GFAP immunoreactivity were present. The mean MIB-1 labeling index remained below 1%. Signs of anaplasia, in particular mitotic figures, endothelial proliferation, or necrosis were consistently lacking. We perceive PGNT as a clinically and morphologically well-delineated subgroup of extraventricular neurocytic neoplasia, whose paradigmatic presentation may allow for consideration as an entity.

Sleep and wakefulness disturbances in Swiss pharmacy customers

BACKGROUND AND OBJECTIVE: Sleep disturbances are prevalent but often overlooked or underestimated. We suspected that sleep disorders might be particularly common among pharmacy customers, and that they could benefit from counselling. Therefore, we described the prevalence and severity of symptoms associated with sleep and wakefulness disorders among Swiss pharmacy customers, and estimated the need for counselling and treatment. METHODS: In 804 Swiss pharmacies (49% of all community pharmacies) clients were invited to complete the Stanford Sleep Disorders Questionnaire (SDQ), and the Epworth Sleepiness Scale (EPW). The SDQ was designed to classify symptoms of sleep and wakefulness into the four most prevalent disorders: sleep apnoea syndrome (SAS), insomnia in psychiatric disorders (PSY), periodic leg movement disorders/restless legs (RLS) and narcolepsy (NAR). Data were entered into an internet-linked database for analysis by an expert system as a basis for immediate counselling by the pharmacist. RESULTS: Of 4901 participants, 3238 (66.1%) were female, and 1663 (33.9%) were male. The mean age (SD) of females and males was 52.4 (18.05), and 55.1 (17.10) years, respectively. The percentages of female and male individuals above cut-off of SDQ subscales were 11.4% and 19.8% for sleep apnoea, 40.9% and 38.7% for psychiatric sleep disorders, 59.3% and 46.8% for restless legs, and 10.4% and 9.4% for narcolepsy respectively. The prevalence of an Epworth Sleepiness Scale score >11 was 16.5% in females, and 23.9% in males. Reliability assessed by Cronbach's alpha was 0.65 to 0.78 for SDQ subscales, and for the Epworth score. CONCLUSIONS: Symptoms of sleep and wakefulness disorders among Swiss pharmacy customers were highly prevalent. The SDQ and the Epworth Sleepiness Scale score had a satisfactory reliability to be useful for identification of pharmacy customers who might benefit from information and counselling while visiting pharmacies. The internet-based system proved to be a helpful tool for the pharmacist when counselling his customers in terms of diagnostic classification and severity of symptoms associated with the sleeping and waking state.

Evaluation of hydroxyapatite cement for frontal sinus obliteration after mucocele resection

OBJECTIVES: To retrospectively evaluate our experience with frontal sinus obliteration using hydroxyapatite cement (BoneSource; Stryker Biotech Europe, Montreux, Switzerland) and compare it with fat obliteration over the approximate same period. Frontal sinus obliteration with hydroxyapatite cement represents a new technique for obliteration of the frontal sinus after mucocele resection. METHODS: Exploration of the frontal sinus was performed using bicoronal, osteoplastic flaps, with mucosal removal and duct obliteration with tissue glue and muscle or fascia. Flaps were elevated over the periorbita, and Silastic sheeting was used to protect the BoneSource material from exposure as it dried. The frontal table was replaced when appropriate. RESULTS: Sixteen patients underwent frontal sinus obliteration with fat (fat obliteration group), and 38 patients underwent obliteration with BoneSource (BoneSource group). Fat obliteration failed in 2 patients, who underwent subsequent BoneSource obliteration, and none of the patients in the BoneSource group has required removal of material because of recurrent complications. Frontobasal trauma (26 patients [68%] in the BoneSource group and 9 patients [56%] in the fat obliteration group) was the most common history of mucocele formation in both groups. Major complications in the BoneSource group included 1 patient with skin fistula, which was managed conservatively, and 1 patient with recurrent ethmoiditis, which was managed surgically. Both complications were not directly attributed to the use of BoneSource. Contour deficit of the frontal bone occurred in 1 patient in the fat obliteration group and in none in the BoneSource group. Two patients in the fat obliteration group had donor site complications (hematoma and infection). Thirteen patients in the BoneSource group had at least 1 prior attempt at mucocele drainage, and no statistical relation existed between recurrent surgery and preservation of the anterior table. CONCLUSION: Hydroxyapatite is a safe, effective material to obliterate frontal sinuses infected with mucoceles, with minimal morbidity and excellent postoperative contour.

Limited redundancy in phosphorylation of retinoblastoma tumor suppressor protein by cyclin-dependent kinases in acute lymphoblastic leukemia

Cyclin-dependent kinases (CDKs) successively phosphorylate the retinoblastoma protein (RB) at the restriction point in G1 phase. Hyperphosphorylation results in functional inactivation of RB, activation of the E2F transcriptional program, and entry of cells into S phase. RB unphosphorylated at serine 608 has growth suppressive activity. Phosphorylation of serines 608/612 inhibits binding of E2F-1 to RB. In Nalm-6 acute lymphoblastic leukemia extracts, serine 608 is phosphorylated by CDK4/6 complexes but not by CDK2. We reasoned that phosphorylation of serines 608/612 by redundant CDKs could accelerate phospho group formation and determined which G1 CDK contributes to serine 612 phosphorylation. Here, we report that CDK4 complexes from Nalm-6 extracts phosphorylated in vitro the CDK2-preferred serine 612, which was inhibited by p16INK4a, and fascaplysin. In contrast, serine 780 and serine 795 were efficiently phosphorylated by CDK4 but not by CDK2. The data suggest that the redundancy in phosphorylation of RB by CDK2 and CDK4 in Nalm-6 extracts is limited. Serine 612 phosphorylation by CDK4 also occurred in extracts of childhood acute lymphoblastic leukemia cells but not in extracts of mobilized CD34+ hemopoietic progenitor cells. This phenomenon could contribute to the commitment of childhood acute lymphocytic leukemia cells to proliferate and explain their refractoriness to differentiation-inducing agents.