Extending the search for neutrino point sources with IceCube above the horizon

Point source searches with the IceCube neutrino telescope have been restricted to one hemisphere, due to the exclusive selection of upward going events as a way of rejecting the atmospheric muon background. We show that the region above the horizon can be included by suppressing the background through energy-sensitive cuts. This improves the sensitivity above PeV energies, previously not accessible for declinations of more than a few degrees below the horizon due to the absorption of neutrinos in Earth. We present results based on data collected with 22 strings of IceCube, extending its field of view and energy reach for point source searches. No significant excess above the atmospheric background is observed in a sky scan and in tests of source candidates. Upper limits are reported, which for the first time cover point sources in the southern sky up to EeV energies.

Abnormal sensorimotor plasticity in organic but not in psychogenic dystonia

Dystonia is characterized by two main pathophysiological abnormalities: 'reduced' excitability of inhibitory systems at many levels of the sensorimotor system, and 'increased' plasticity of neural connections in sensorimotor circuits at a brainstem and spinal level. A surprising finding in two recent papers has been the fact that abnormalities of inhibition similar to those in organic dystonia are also seen in patients who have psychogenic dystonia. To try to determine the critical feature that might separate organic and psychogenic conditions, we investigated cortical plasticity in a group of 10 patients with psychogenic dystonia and compared the results with those obtained in a matched group of 10 patients with organic dystonia and 10 healthy individuals. We confirmed the presence of abnormal motor cortical inhibition (short-interval intracortical inhibition) in both organic and psychogenic groups. However, we found that plasticity (paired associative stimulation) was abnormally high only in the organic group, while there was no difference between the plasticity measured in psychogenic patients and healthy controls. We conclude that abnormal plasticity is a hallmark of organic dystonia; furthermore it is not a consequence of reduced inhibition since the latter is seen in psychogenic patients who have normal plasticity.

Olfaction in patients with suspected parkinsonism and scans without evidence of dopaminergic deficit (SWEDDs)

BACKGROUND

Positron emission tomography and single photon emission computed tomography scanning have 87-94% sensitivity and 80-100% specificity to differentiate patients with Parkinson's disease (PD) from control subjects and patients with essential (ET) or atypical tremor. More than 10% of patients diagnosed as early PD can have scans without evidence of dopaminergic deficiency (SWEDDs). This study investigated whether smell tests can help identify possible cases with SWEDDs.

METHODS

The 40 item University of Pennsylvania Smell Test (UPSIT) was used to evaluate the sense of smell in 21 SWEDDs patients. Twenty-six ET patients, 16 patients with a diagnosis of idiopathic adult onset dystonia (D), 191 non-demented PD patients and 136 control subjects were also tested. Multiple regression analyses were used to compare the mean UPSIT score in the SWEDDs group with the other four groups (ET, D, PD and controls) after adjusting for the effects of relevant covariates.

RESULTS

The mean UPSIT score for the SWEDDs group was greater than in the PD group (p<0.001) and not different from the mean UPSIT in the control (p = 0.7), ET (p = 0.4) or D (p = 0.9) groups. Smell tests indicated a high probability of PD in only 23.8% of SWEDDs as opposed to 85.3% of PD patients.

CONCLUSIONS

In a patient with suspected PD, a high PD probability on smell testing favours the diagnosis of PD, and a low PD probability strengthens the indication for dopamine transporter imaging.

Limits on a muon flux from neutralino annihilations in the sun with the IceCube 22-string detector

A search for muon neutrinos from neutralino annihilations in the Sun has been performed with the IceCube 22-string neutrino detector using data collected in 104.3 days of live time in 2007. No excess over the expected atmospheric background has been observed. Upper limits have been obtained on the annihilation rate of captured neutralinos in the Sun and converted to limits on the weakly interacting massive particle (WIMP) proton cross sections for WIMP masses in the range 250-5000 GeV. These results are the most stringent limits to date on neutralino annihilation in the Sun.

[The role of laparoscopy in ovarian carcinoma]

The role of minimally invasive surgery in the management of gynecologic cancers is continuously expanding. Although few trials have focused on the safety of laparoscopy in oncology, laparoscopy is now widely used for most gynecological malignancies. Laparoscopy is widely used to manage benign ovarian masses, but its role in managing ovarian cancer still needs to be defined. The role of laparoscopy in ovarian cancer surgery may be divided into three following categories: 1) laparoscopic staging of apparent early ovarian cancer; 2) laparoscopic assessment of disease extent and potential for resectability; 3) laparoscopic reassessment, or second-look operation, or rule out recurrence. Laparoscopic approach has shown several advantages like a reduction in operating time, blood loss, hospital stay, and total hospital charges. The limitations of laparoscopic practice include inadequate port-site metastasis, tumour dissemination due to cyst rupture and incomplete staging. In addition, there were limitations in performing extensive laparoscopic sampling of areas of tumor persistence including retroperitoneal lymph nodes. In literature there are no randomized studies assessing the use of laparoscopy in the management of ovarian cancer. Moreover, most of the studies in literature comparing laparoscopy and laparotomy are carried out by surgeons specialized in one of two approaches, so that the results can not be compared.

Abnormal plasticity of sensorimotor circuits extends beyond the affected body part in focal dystonia

OBJECTIVE

To test whether abnormal sensorimotor plasticity in focal hand dystonia is a primary abnormality or is merely a consequence of the dystonic posture.

METHODS

This study used the paired associative stimulation (PAS) paradigm, an experimental intervention, capable of producing long term potentiation (LTP) like changes in the sensorimotor system in humans. PAS involves transcranial magnetic stimulation combined with median nerve stimulation. 10 patients with cranial and cervical dystonia, who showed no dystonic symptoms in the hand, and nine patients with hemifacial spasm (HFS), a non-dystonic condition, were compared with 10 healthy age matched controls. Motor evoked potential amplitudes and cortical silent period (CSP) duration were measured at baseline before PAS and for up to 60 min (T0, T30 and T60) after PAS in the abductor pollicis brevis and the first dorsal interosseus muscles.

RESULTS

Patients with dystonia showed a stronger increase in corticospinal excitability than healthy controls and patients with HFS. In addition, patients with dystonia showed a loss of topographical specificity of PAS induced effects, with a facilitation in both the median and ulnar innervated muscles. While PAS conditioning led to a prolonged CSP in healthy controls and patients with HFS, it had no effect on the duration of the CSP in patients with cranial and cervical dystonia.

CONCLUSION

The data suggests that excessive motor cortex plasticity is not restricted to the circuits clinically affected by dystonia but generalises across the entire sensorimotor system, possibly representing an endophenotypic trait of the disease.

Two new highly polymorphic markers in the 3' UTR region of the PLA2G7 gene

We described two new highly polymorphic markers located 31 bp downstream of the last nucleotide of exon 12 in the 3' UTR region of the gene PLA2G7: 1344 +31TG(n) AG(m). Eight and 14 alleles were observed for the AG and TG repeats, respectively. These two markers have the highest heterozygosity until now reported for PLA2G7 gene.