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Photodissociation of vibrationally and electronically excited sulfur dimer molecules (S2) has been studied in a combined experimental and computational quantum chemistry study in order to characterize bound-continuum transitions. Ab initio quantum chemistry calculations are carried out to predict the potential energy curves, spin-orbit coupling, transition moments, and bound-continuum spectra of S2 for comparison with the experimental data. The experiment uses velocity map imaging to measure S-atom production following S2 photoexcitation in the ultraviolet region (320-205 nm). A pulsed electric discharge in H2S produces ground-state S2 X3ςg -(v = 0-15) as well as electronically excited singlet sulfur and b1ςg +(v = 0, 1), and evidence is presented for the production and photodissociation of S2 a1Δg. In a previous paper, we reported threshold photodissociation of S2X3ςg -(v = 0) in the 282-266 nm region. In the present study, S(3PJ) fine structure branching and angular distributions for photodissociation of S2 (X3ςg -(v = 0), a1Δg and b1ςg +) via the B″3IIu, B3ςu - and 11IIu excited states are reported. In addition, photodissociation of the X3ςg -(v = 0) state of S2 to the second dissociation limit producing S(3P2) + S(1D) is characterized. The present results on S2 photodynamics are compared to those of the well-studied electronically isovalent O2 molecule.

In newly diagnosed multiple myeloma (MM), patients ineligible for front-line autologous stem cell transplantation (ASCT), melphalan and prednisone (MP) with thalidomide (MPT) or bortezomib (VMP) are standard first-line therapeutic options. Despite new treatment regimens incorporating bortezomib or lenalidomide, MM remains incurable. The FIRST study demonstrated significant improvement in progression-free survival (PFS) and overall survival (OS) for the combination of lenalidomide and low-dose dexamethasone (Rd) until progression vs. MPT in transplant-ineligible ndMM patients. However, to date no head-to-head randomized controlled trials (RCTs) have compared Rd or MPT versus VMP. We conducted a network meta-analysis using RCTs identified through a systematic literature review to evaluate the relative efficacy of Rd versus other regimens on survival endpoints in previously untreated MM patients ineligible for ASCT. In this analysis, Rd was associated with a significant PFS and survival advantage versus other first-line treatments (VMP, MPT, MP), challenging the role of alkylators in this setting. © 2016 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

Objective: To examine whether risk factor profile, baseline features, and outcome of cervical artery dissection (CEAD) differ according to the dissection site. Methods: We analyzed 982 consecutive patients with CEAD included in the Cervical Artery Dissection and Ischemic Stroke Patients observational study (n = 619 with internal carotid artery dissection [ICAD], n = 327 with vertebral artery dissection [VAD], n = 36 with ICAD and VAD). Results: Patients with ICAD were older ( p p = 0.006), more frequently had a recent infection (odds ratio [OR] = 1.59 [95% confidence interval (CI) 1.09–2.31]), and tended to report less often a minor neck trauma in the previous month (OR = 0.75 [0.56–1.007]) compared to patients with VAD. Clinically, patients with ICAD more often presented with headache at admission (OR = 1.36 [1.01–1.84]) but less frequently complained of cervical pain (OR = 0.36 [0.27–0.48]) or had cerebral ischemia (OR = 0.32 [0.21–0.49]) than patients with VAD. Among patients with CEAD who sustained an ischemic stroke, the NIH Stroke Scale (NIHSS) score at admission was higher in patients with ICAD than patients with VAD (OR = 1.17 [1.12–1.22]). Aneurysmal dilatation was more common (OR = 1.80 [1.13–2.87]) and bilateral dissection less frequent (OR = 0.63 [0.42–0.95]) in patients with ICAD. Multiple concomitant dissections tended to cluster on the same artery type rather than involving both a vertebral and carotid artery. Patients with ICAD had a less favorable 3-month functional outcome (modified Rankin Scale score >2, OR = 3.99 [2.32–6.88]), but this was no longer significant after adjusting for baseline NIHSS score. Conclusion: In the largest published series of patients with CEAD, we observed significant differences between VAD and ICAD in terms of risk factors, baseline features, and functional outcome.

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Autosomal recessive progressive external ophthalmoplegia is a mitochondrial disease characterized by accumulation of multiple large-scale deletions of mitochondrial DNA. We previously reported missense mutations in POLG, the gene encoding the mitochondrial DNA polymerase gamma in two nuclear families compatible with autosomal recessive progressive external ophthalmoplegia. Here, we report a novel POLG missense mutation (R627W) in a sporadic patient and we provide genetic support that all these POLG mutations are actually causal and recessive. The novel patient presented with sensory ataxic neuropathy and has the clinical triad of sensory ataxic neuropathy, dysarthria and ophthalmoparesis (SANDO). This is the first finding of a genetic cause of Sensory Ataxic Neuropathy, Dysarthria and Ophthalmoparesis and it implies that this disorder may actually be a variant of autosomal recessive progressive external ophthalmoplegia. Sensory neuropathy is the initial feature in Belgian compound heterozygote autosomal recessive progressive external ophthalmoplegia patients, all carrying the POLG A467T mutation, which occurs at a frequency of 0.6% in the Belgian population.

To investigate various cerebrospinal fluid (CSF) markers that could assist in the clinical diagnosis of Creutzfeldt-Jakob disease (CJD).CSF samples were analysed for the presence of 14-3-3 protein, microtubule associated protein tau, and beta amyloid in 250 patients with possible CJD. Densitometric analysis was used to quantify the level of 14-3-3 in all patients.Analysis of the clinical data showed that cerebellar signs or myoclonus combined with progressive dementia were the main features leading to a clinical suspicion of CJD. While 14-3-3 detection had a sensitivity of 100% and a specificity of 92%, tau determination using a threshold of 1300 pg/ml had a sensitivity of 87% and a specificity of 97%. If the protocol for the analysis of 14-3-3 was modified (using densitometric analysis) a higher specificity (97%) could be obtained, but with a lower sensitivity (96%). Maximum sensitivity, specificity, and positive predictive value were obtained with a combination of 14-3-3 and beta amyloid determinations. The concentrations of 14-3-3 and tau in the CSF were reduced in CJD patients with a long duration of disease (more than one year; p0.05). The concentrations of 14-3-3 or tau were lowest at the onset or at the end stage of the disease, while the beta amyloid concentration remained low throughout the course of the disease.Both 14-3-3 and tau protein are sensitive and specific biomarkers for CJD. The combination of 14-3-3 and beta amyloid analysis resulted in the maximum sensitivity, specificity, and positive predictive value. When these biomarkers are used in the diagnosis of CJD, the phase of the disease in which the CSF sample was obtained should be taken into account. Disease duration, dependent on the PrP genotype, also has a significant influence on the level of 14-3-3 and tau in the CSF.

Muscle biopsy tissue from a patient affected by the juvenile form of neuronal ceroid lipofuscinosis (NCL) was studied immunohistochemically using antibodies to beta-amyloid peptide and amyloid precursor protein. Positive reaction in muscle was specifically localized to autophagic vacuoles and blood vessel walls. Increased acid phosphatase reaction suggested enhanced lysosomal activity. We hypothesize that beta-amyloid is deposited in NCL muscle by a lysosomal mechanism similar to that proposed in other disorders involving beta-amyloid.

The inherited neuropathies of the peripheral nervous system are clinically and genetically a heterogeneous group of disorders. Molecular genetic studies have made major breakthroughs in unraveling the underlying gene defects, and DNA diagnosis can now be offered to a large number of families with distinct forms of hereditary peripheral neuropathies. With the currently available technology, however, molecular genetic diagnosis still remains a labor-intensive and costly procedure. We have developed an algorithm for mutation screening based on clinical phenotype, electrophysiological findings, and the relative frequencies of mutations in the distinct peripheral myelin genes.

We have developed a photolytic method to determine the concentration of reactive hemes in a solution in the presence of a trace amount of CO. By measurement of the bimolecular rate of CO binding, and by calibration of the rate constant under equivalent conditions, the concentration of the reactive hemes can be determined. In a solution of sickle hemoglobin, the molecules in the gel contribute negligibly to the recombination rate, allowing the concentration of the molecules in the solution phase to be determined. To optimize signal to noise, modulated excitation methods were employed, although the method could also be used with pulse techniques and suitable signal averaging. Because the optical method employs a microspectrophotometer, only a few microliters of concentrated Hb solution is required to reproduce the entire temperature dependence of the solubility previously determined by centrifugation using milliliter quantities of solutions of the same concentration. This should be especially useful for studies of site-directed mutants, and we present results obtained on one such HbS in which Leu 88 beta has been replaced by Ala. The free energy difference in the polymerization of the Leu 88 beta double mutant is consistent with known differences in the amino acid hydrophobicities. The calibration required for these experiments also provides an excellent determination of the activation energy for binding the first CO to deoxy Hb.

One of the major pathological hallmarks of Alzheimer's disease is the deposition in the brain parenchyma and cerebral blood vessel walls of amyloid beta-protein, a 4 kDa proteolytic product of the longer beta-amyloid precursor protein (APP). Six different single base mutations in the APP gene have been reported causing early-onset Alzheimer's disease (age at onset less than or equal to 65 years) or related amyloidosis in a small number of families. Cell transfection experiments using wild-type and mutant APP cDNA indicated that APP mutations result in the production of more or longer, aggregation prone, A beta peptides.

We describe a family with an autosomal dominant form of retinal-cerebellar atrophy. There is an extreme variability in age of onset and severity of the clinical symptoms: some patients remain nearly asymptomatic throughout their entire life; others develop severe retinal and cerebellar symptoms after the age of 35 years; others suffer from a severe disorder with onset in adolescence and death during the third decade of life; in others the onset is in early childhood with prevalence of cerebellar symptoms. There is neither dementia nor epilepsy in any of the patients. Four out of five autopsies showed, a severe retinal atrophy, and all five autopsies were also characterized by (1) a cerebellar atrophy affecting the spinocerebellar and olivocerebellar tracts, the cerebellar cortex and the efferent cerebellar pathways, (2) an involvement of the pyramidal pathways and of the motor neurons of brain stem and spinal cord, and (3) an atrophy of the subthalamic nucleus and to a much lesser extent of the pallidum, with also some damage to the substantia nigra. The posterior columns are much less affected except in one patient. In this family, we have excluded linkage with the two loci for spinocerebellar ataxia, i.e., SCA1 on chromosome 6p and SCA2 on chromosome 12q as well as with the locus for Machado-Joseph disease (MJD) on chromosome 14q. A genome-wide search is currently being performed to detect the disease locus responsible.

Hereditary motor and sensory neuropathy type I (HMSN I) or Charcot-Marie-Tooth disease type 1 (CMT 1) is an autosomal dominant disorder of the peripheral nervous system characterized by progressive weakness and atrophy of distal limb muscles. In the majority of HMSN I families, linkage studies localized the gene (CMT 1a) to the pericentromeric region of chromosome 17. We have detected with probe pVAW409R3 (D17S122) localized in 17p11.2 a duplication, co-segregating with the disease in 12 HMSN I families. In these families the duplication was present in all 128 patients but absent in the 84 unaffected and 44 married-in individuals (lod score of 58.44 at zero recombination). Further, on one HMSN I family the disease newly appeared simultaneously with a de novo duplication originating from an unequal crossing-over event at meiosis. Since different allelic combinations were found segregating with the duplication in different families linkage disequilibrium was not a significant factor. These findings led us to propose that the duplication in 17p11.2 itself is the disease causing mutation in all the HMSN I families analyzed.

In two siblings affected with dementia, epilepsy and vertical supranuclear ophthalmoplegia, foam cells and sea-blue histiocytes were found in the bone marrow. Electron microscopy of skin and neuromuscular biopsies gave presumptive evidence in favour of a storage disorder. Postmortem examination of both cases revealed an intraneuronal polymorphous lysosomal storage in the central nervous system (in the cortex and in many nuclei e.g. the substantia nigra and the reticular formation of the brain stem). In the visceral organs with the spleen most severely affected, the inclusions had a different ultrastructure, being composed of tightly apposed leaflets. The biochemical study revealed accumulation of sphingomyelin and other lipids in liver and spleen, with normal sphingomyelinase activities, which is consistent with the diagnosis of Niemann-Pick disease type C. In the brain, the most striking abnormalities involved the glycolipids. Sphingomyelinase activities were unchanged in cultivated skin fibroblasts. These data compared with those of reported cases, allowed the following conclusions to be made: (1) although the combination of clinical features appears to be unique, none of them, when considered separately, is pathognomonic for juvenile dystonic lipidosis; (2) diagnosis during life can be suggested by careful examination of nerve bundles and fibroblasts with the electron microscope, although the method of choice appears to be the study of bone marrow; but final assessment of the diagnosis, in the absence of demonstrable enzymic deficiency, requires in most cases a study of the lipid profile in a liver biopsy (or better, spleen tissue whenever available); (3) the intralysosomal storage is different, both morphologically and biochemically, in the central nervous system and in the spleen; (4) juvenile dystonic lipidosis represents a juvenile variant of Niemann-Pick disease type C, pending the discovery of the primary defect responsible for this disorder.

During the 3 weeks of his life, an infant born at term presented pronounced hypotonia, areflexia and generalized paresis with severe respiratory and feeding problems. He was the fourth male in two generations to die in the perinatal period, therefore suggesting an X-linked inheritance. Post-mortem examination revealed a centronuclear or myotubular myopathy. The difficulty in distinguishing the signs due to muscle disorder from those due to hypoxaemic encephalopathy is stressed. Infants with centronuclear myopathy have in any case a high risk for hypoxaemic encephalopathy. The literature concerning neonatal centronuclear myopathy with X-linked inheritance is reviewed.

A 3-year-old boy was referred for evaluation of psychomotor retardation. He had a waddling gait with proximal hypotonia and paresis. Computed tomography (CT scan) and magnetic resonance imaging (MRI) of the brain demonstrated symmetrical lesions in the basal ganglia suggesting bilateral necrosis. Lactate and pyruvate levels in blood and cerebrospinal fluid were persistently elevated. A biopsy of the quadriceps muscle showed normal light microscopic findings except for a slightly raised number of lipid droplets. Electron microscopy confirmed this and also showed a rather large number of subsarcolemmal mitochondria without crystalline inclusions. Biochemical studies showed a normal carnitine level and normal mitochondrial enzyme activities in muscle homogenate, including succinate-cytochrome c reductase. However, intact isolated mitochondria failed to oxidize succinate. An explanation for this paradoxical finding is a deficiency in that part of the coenzyme Q (CoQ) that is reduced by the succinate dehydrogenase complex. The differential diagnosis between Leigh's syndrome and infantile bilateral striatal necrosis (IBSN) is discussed. The role of neuroradiology in prompting complementary investigations is stressed.

In a sibship of ten, three brothers presented with an adult form of ceroid-lipofuscinosis. The diagnosis was confirmed by necropsy of the first patient and was made by electron microscopy of eccrine sweat glands and of skeletal muscles in the two others. Somatosensory evoked potentials were characterised by biphasic, nearly monophasic, very high voltage complexes totally unlike those found in normal controls. Similar sensory evoked potentials were however recorded in other types of ceroid-lipofuscinosis. While electron microscopy of easily available tissues gives fairly specific results, sensory evoked potentials can bring supportive diagnostic evidence in adult ceroid-lipofuscinosis.