Part of the neutrino events collected in 1994-1995 by the CHORUS experiment has been analysed. A search was performed for
ν
τ
charged current interactions followed by the
τ lepton decay into a single ...charged negative hadron, a possible indication for ν
μ→ν
τ oscillation. A sample of 6844 events without an identified muon has been located in the emulsion target. Within the selection criteria, no
τ
− candidate has been found. Combining this result with the one from the search for
ν
τ
interactions using the muonic decay mode (36
182 events with an identified muon), a 90% C.L. limit on the mixing angle sin
22
θ
μτ
<1.8·10
−3 (at large
Δm
2) has been derived.
We report on the first direct observation of a neutrino induced charged-current interaction with two subsequent decays of short-lived particles close to the interaction vertex. This rare double-kink ...signature in the CHORUS emulsion target is interpreted as a
D
s
∗+
production followed by the decay chain
D
s
∗+→D
s
+γ,D
s
+→τ
+ν
τ,
τ
+→μ
+ν
μ
ν
τ
̄
. The event is characterised by small
Q
2 and small four-momentum transfer squared
t to the target nucleon, which indicates a diffractive production mechanism. A complete analysis of the event is presented.
Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is known as a therapy of choice of advanced Parkinson's disease. The present study aimed to assess the beneficial and side effects of STN ...DBS in Moroccan Parkinsonian patients.
Thirty five patients underwent bilateral STN DBS from 2008 to 2016 in the Rabat University Hospital. Patients were assessed preoperatively and followed up for 6 to 12 months using the Unified Parkinson's Disease Rating Scale in four conditions (stimulation OFF and ON and medication OFF and ON), the levodopa-equivalent daily dose (LEDD), dyskinesia and fluctuation scores and PDQ39 scale for quality of life (QOL). Postoperative side effects were also recorded.
The mean age at disease onset was 42.31 ± 7.29 years 28-58 and the mean age at surgery was 54.66 ± 8.51 years 34-70. The median disease duration was 11.95 ± 4.28 years 5-22. Sixty-three percentage of patients were male. 11.4% of patients were tremor dominant while 45.71 showed akinetic-rigid form and 42.90 were classified as mixed phenotype. The LEDD before surgery was 1200 mg/day 800-1500. All patients had motor fluctuations whereas non-motor fluctuations were present in 61.80% of cases. STN DBS decreased the LEDD by 51.72%, as the mean LEDD post-surgery was 450 188-800. The UPDRS-III was improved by 52.27%, dyskinesia score by 66.70% and motor fluctuations by 50%, whereas QOL improved by 27.12%. Post-operative side effects were hypophonia (2 cases), infection (3 cases), and pneumocephalus (2 cases).
Our results showed that STN DBS is an effective treatment in Moroccan Parkinsonian patients leading to a major improvement of the most disabling symptoms (dyskinesia, motor fluctuation) and a better QOL.
BACKGROUND: Detection of cardiac fibrosis based on endogenous magnetic resonance (MR) characteristics of the myocardium would yield a measurement that can provide quantitative information, is ...independent of contrast agent concentration, renal function and timing. In ex vivo myocardial infarction (MI) tissue, it has been shown that a significantly higher T1ρ is found in the MI region, and studies in animal models of chronic MI showed the first in vivo evidence for the ability to detect myocardial fibrosis with native T1ρ-mapping. In this study we aimed to translate and validate T1ρ-mapping for endogenous detection of chronic MI in patients. METHODS: We first performed a study in a porcine animal model of chronic MI to validate the implementation of T1ρ-mapping on a clinical cardiovascular MR scanner and studied the correlation with histology. Subsequently a clinical protocol was developed, to assess the feasibility of scar tissue detection with native T1ρ-mapping in patients (n = 21) with chronic MI, and correlated with gold standard late gadolinium enhancement (LGE) CMR. Four T1ρ-weighted images were acquired using a spin-lock preparation pulse with varying duration (0, 13, 27, 45 ms) and an amplitude of 750 Hz, and a T1ρ-map was calculated. The resulting T1ρ-maps and LGE images were scored qualitatively for the presence and extent of myocardial scarring using the 17-segment AHA model. RESULTS: In the animal model (n = 9) a significantly higher T1ρ relaxation time was found in the infarct region (61 ± 11 ms), compared to healthy remote myocardium (36 ± 4 ms) . In patients a higher T1ρ relaxation time (79 ± 11 ms) was found in the infarct region than in remote myocardium (54 ± 6 ms). Overlap in the scoring of scar tissue on LGE images and T1ρ-maps was 74%. CONCLUSION: We have shown the feasibility of native T1ρ-mapping for detection of infarct area in patients with a chronic myocardial infarction. In the near future, improvements on the T1ρ -mapping sequence could provide a higher sensitivity and specificity. This endogenous method could be an alternative for LGE imaging, and provide additional quantitative information on myocardial tissue characteristics.
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