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Diffusion MRI paired with tractography has facilitated a non-invasive exploration of many association, projection, and commissural fiber tracts. However, there is still a scarcity of research studies related to intralobar association fibers. The Dejerines' (two of the most notable neurologists of 19th century France) gave an in-depth description of the intralobar fibers of the occipital lobe. Unfortunately, their exquisite work has since been sparsely cited in the modern literature. This work gives a modern description of many of the occipital intralobar lobe fibers described by the Dejerines. We perform a virtual dissection and reconstruct the tracts using diffusion MRI tractography. The dissection is guided by the Dejerines' treatise, Anatomie des Centres Nerveux. As an accompaniment to this article, we provided a French-to-English translation of the treatise portion concerning five intra-occipital tracts, namely: the stratum calcarinum, the stratum proprium cunei, the vertical occipital fasciculus of Wernicke, the transverse fasciculus of the cuneus and the transverse fasciculus of the lingual lobule of Vialet. It was possible to reconstruct all but one of these tracts. For completeness, the recently described sledge runner fasciculus, although not one of the Dejerines' tracts, was identified and successfully reconstructed. Bugain et al perform a virtual dissection and reconstruct the occipital intralobar tracts using diffusion MRI tractography. They provide a modern anatomical depiction of what had originally been described by the Dejerines in the 19th century, as well as a complete translation of the original text. [ABSTRACT FROM AUTHOR]

Three major white matter pathways connect the posterior temporal region and the adjacent inferior parietal lobule with the lateral frontal cortex: the arcuate fasciculus (AF), and the second and third branches of the superior longitudinal fasciculus (SLF II and SLF III). These pathways are found also in nonhuman primate brains where they play specific roles in auditory and spatial processing. The precise origin, course, and termination of these pathways has been examined in invasive tract tracing studies in macaque monkeys. Here we use this prior knowledge to improve dissections of these pathways in vivo in the human brain using diffusion Magnetic Resonance Imaging (MRI) tractography. In this study, the AF, originating from the posterior temporal cortex, has been successfully separated from the SLF II and SLF III tracts originating from the angular and supramarginal gyri of the inferior parietal lobule, respectively. The latter two pathways, i.e. SLF II and SLF III, have also been clearly separated from each other. Furthermore, we report for the first time in the human brain the dorsal branch of the AF that targets the posterior dorsolateral frontal region. These improved dissection protocols provide a solid basis for exploring the respective functional roles of these major fasciculi. [ABSTRACT FROM AUTHOR]

Objectives: To assess the diagnostic performance of median nerve (MN) flip-angle measurements, deformation during wrist flexion [transit deformation coefficient (TDC)], during compression [compression deformation coefficient (CDC)] and fascicular freedom to potentially identify fibrotic MN changes in patients with carpal tunnel syndrome (CTS).Methods: This prospective study was performed with institutional review board approval; all participants provided oral and written informed consent. Wrists in 21 healthy participants and 29 patients with CTS were examined by ultrasound. MN movement during wrist flexion, MN deformation during transition over the flexor tendons (TDC) and during controlled compression (CDC) as well as fascicular freedom were assessed. Diagnostic properties of these parameters were calculated and compared to clinical findings and cross-section area measurements (ΔCSA).Results: Low flip angles were associated with high ΔCSA at a receiver-operator characteristics area under the curve (AUC) of 0.62 (0.51-0.74). TDC [AUC, 0.83 (0.73-0.92), 76.3% (59.8-88.6%) sensitivity, 88.5% (76.6-95.7%) specificity], restricted fascicular movement [AUC, 0.86 (0.78-0.94), 89.5% (75.2-97.1%) sensitivity, 80.8% (67.5-90.4%) specificity] and compression-based CDC [AUC, 0.97 (0.94-1.00), 82.1% (66.5-92.5%) sensitivity, 94.2% (84.1-98.8%) specificity] demonstrated substantial diagnostic power (95% confidence intervals in parentheses).Conclusions: Fascicular mobility, TDC and CDC show substantial diagnostic power and may offer insights into the underlying pathophysiology of CTS.Key Points: • Dynamic ultrasonography during wrist flexion and compression enables median nerve deformability assessment. • Overall, reduced median nerve deformability is highly indicative of CTS. • Median nerve compressibility shows higher diagnostic power than conventional cross-section area measurements. [ABSTRACT FROM AUTHOR]

Abstract Purpose We propose a new along-tract algorithm to compare different tractography algorithms in tract curvature mapping and along-tract analysis of the arcuate fasciculus (AF). In particular, we quantified along-tract diffusion parameters and AF spatial distribution evaluating hemispheric asymmetries in a group of healthy subjects. Methods The AF was bilaterally reconstructed in a group of 29 healthy subjects using the probabilistic ball-and-sticks model, and both deterministic and probabilistic constrained spherical deconvolution. We chose cortical ROIs as tractography targets and the developed along-tract algorithm used the Laplacian operator to parameterize the volume of the tract, allowing along-tract analysis and tract curvature mapping independent of the tractography algorithm used. Results The Laplacian parameterization successfully described the tract geometry underlying hemispheric asymmetries in the AF curvature. Using the probabilistic tractography methods, we found more tracts branching towards cortical terminations in the left hemisphere. This influenced the left AF curvature and its diffusion parameters, which were significantly different with respect to the right. In particular, we detected projections towards the middle temporal and inferior frontal gyri bilaterally, and towards the superior temporal and precentral gyri in the left hemisphere, with a significantly increased volume and connectivity. Conclusions The approach we propose is useful to evaluate brain asymmetries, assessing the volume, the diffusion properties and the quantitative spatial localization of the AF. [ABSTRACT FROM AUTHOR]

Background Microvascular decompression for hemifacial spasm is performed at the root exit zone. More proximal segments of the facial nerve, defined as the root emerging zone (REmZ), may also be susceptible to neurovascular compression. Consequently, detailed knowledge of the microanatomy around facial nerve fibers at the pontomedullary junction is essential for consistent success of microvascular decompression. Methods Five human brainstems obtained from cadavers were investigated using correlative light microscopy and block-face imaging, which obtains arbitrary two-dimensional light microscopic and three-dimensional volume data from a single specimen. The entire facial nerve pathway, including the myelin transition, was evaluated inside and outside the brainstem. Results Correlative light microscopy and block-face imaging showed the intra-brainstem facial nerve fibers emerging at the brainstem surface deep at the pontomedullary sulcus (REmZ) and coursing along the pontine surface before detaching from the pons (root exit zone). An acute emerging angle significantly increased the surface area with central myelin. The facial nerve bundle formed 1 fasciculus in the portion covered by central myelin but divided into 2 fasciculi in the myelin transitional portion and then into multiple fasciculi more distally. Arteries around the REmZ were often anchored by perforating branches entangled with lower cranial nerves. Conclusions Facial nerve fibers are susceptible to vascular compression on emerging onto the deep brainstem surface at the pontomedullary sulcus. The key procedure in microvascular decompression is full dissection of the lower cranial nerves down to the brainstem origin to explore both the root exit zone and the REmZ. Highlights • Facial nerve fibers emerge at the brainstem surface deep at the pontomedullary sulcus. • An acute emerging angle significantly increases the surface area with central myelin. • The facial nerve bundle divides into multiple fasciculi around the myelin transitional portion. • Arteries around the REmZ were often anchored by perforating branches. • Full dissection of lower cranial nerves is a key procedure in MVD. [ABSTRACT FROM AUTHOR]

This study aimed to quantitatively analyze fasciculation potentials (FPs) and to investigate their relationship with muscle strength in amyotrophic lateral sclerosis (ALS). Fifty-one patients with sporadic ALS or progressive muscular atrophy (25 men, 26 women, mean age of 68 years) underwent needle EMG. We determined the duration, phase number, and amplitude of FPs from three muscles (upper trapezius, biceps brachii, and tibialis anterior) and examined their relations with muscle strength. In total, 878 FPs were analyzed. FP duration displayed a significant negative relation with the strength of all three muscles; the weaker muscles showed longer durations of FPs than the muscles with normal strength. The amplitude and phase number were not related with muscle strength, but there were significant correlations between the duration and amplitude of FPs in the trapezius and tibialis anterior muscles. The longer duration of FPs in muscles with weak strength suggests that the morphological changes of FPs were caused by temporal dispersion through progressively degenerating and/or immature reinnervating motor branches, and were observed uniformly in different muscles along with disease progression. [ABSTRACT FROM AUTHOR]

Objective: The middle interhemispheric (MIH) variant of holoprosencephaly (HPE) is the incomplete separation of midline cerebral hemispheres with the absence of callosal body. We aimed to describe the additional knowledge of diffusion tensor imaging (DTI) over conventional MRI in the evaluation of patients with MIH variant of HPE. Methods: Conventional MRI and DTI data of five patients were retrospectively evaluated. The parenchymal anomalies as well as changes at white matter tracts were systematically reviewed. Results: Except the callosal body and central cingulum fibres, which were missing in all patients, all other major white matter tracts (superior and inferior longitudinal, superior and inferior fronto-occipital, subcallosal and uncinate fasciculi and anterior commissure) had a normal course, thickness and integrity on diffusion tensor images. The genial and splenial callosal fibres were altered and rarefied on tractography. All patients had a central ventricular notch extending into the non-cleaved heterotopic grey matter involving the body of the corpus callosum, which is very typical for the MIH variant of HPE. The remnant traversing white matter fibres above the non-cleaved heterotopic grey matter and incomplete partition of the interhemispheric fissure were also identified. No Probst bundles were detected. A single common ventricle without the septum pellucidum was noted in all patients. One patient had incomplete partition of the thalami, and two patients had abnormally oriented thalami without any prominent interthalamic connection. Vertically oriented hippocampi were detected in four out of five patients. Three patients had relatively flat and vertically oriented Sylvian fissures and in two patients, fissures were abnormally connected over the vertex. Conclusion: Additional DTI findings can not only clearly reveal the white matter alterations better than conventional MRI but also provide a better understanding of the aetiological changes that cause the MIH variant of HPE. Advances in knowledge: DTI can provide a better analysis of cerebral white matter connectivity and promotes understanding of the underlying microstructural changes that occur in patients with the MIH variant of HPE. [ABSTRACT FROM AUTHOR]

It has been postulated that autism spectrum disorder is underpinned by an 'atypical connectivity' involving higher-order association brain regions. To test this hypothesis in a large cohort of adults with autism spectrum disorder we compared the white matter networks of 61 adult males with autism spectrum disorder and 61 neurotypical controls, using two complementary approaches to diffusion tensor magnetic resonance imaging. First, we applied tract-based spatial statistics, a 'whole brain' non-hypothesis driven method, to identify differences in white matter networks in adults with autism spectrum disorder. Following this we used a tract-specific analysis, based on tractography, to carry out a more detailed analysis of individual tracts identified by tract-based spatial statistics. Finally, within the autism spectrum disorder group, we studied the relationship between diffusion measures and autistic symptom severity. Tract-based spatial statistics revealed that autism spectrum disorder was associated with significantly reduced fractional anisotropy in regions that included frontal lobe pathways. Tractography analysis of these specific pathways showed increased mean and perpendicular diffusivity, and reduced number of streamlines in the anterior and long segments of the arcuate fasciculus, cingulum and uncinate--predominantly in the left hemisphere. Abnormalities were also evident in the anterior portions of the corpus callosum connecting left and right frontal lobes. The degree of microstructural alteration of the arcuate and uncinate fasciculi was associated with severity of symptoms in language and social reciprocity in childhood. Our results indicated that autism spectrum disorder is a developmental condition associated with abnormal connectivity of the frontal lobes. Furthermore our findings showed that male adults with autism spectrum disorder have regional differences in brain anatomy, which correlate with specific aspects of autistic symptoms. Overall these results suggest that autism spectrum disorder is a condition linked to aberrant developmental trajectories of the frontal networks that persist in adult life. [ABSTRACT FROM AUTHOR]

This paper introduces a Bidirectional Iterative Parcellation ( BIP ) procedure designed to identify the location and size of connected cortical regions ( parcellations ) at both ends of a white matter tract in diffusion weighted images. The procedure applies the FSL option “probabilistic tracking with classification targets” in a bidirectional and iterative manner. To assess the utility of BIP, we applied the procedure to the problem of parcellating a limited set of well-established gray matter seed regions associated with the dorsal (arcuate fasciculus/superior longitudinal fasciculus) and ventral (extreme capsule fiber system) white matter tracts in the language networks of 97 participants. These left hemisphere seed regions and the two white matter tracts, along with their right hemisphere homologues, provided an excellent test case for BIP because the resulting parcellations overlap and their connectivity via the arcuate fasciculi and extreme capsule fiber systems are well studied. The procedure yielded both confirmatory and novel findings. Specifically, BIP confirmed that each tract connects within the seed regions in unique, but expected ways. Novel findings included increasingly left-lateralized parcellations associated with the arcuate fasciculus/superior longitudinal fasciculus as a function of age and education. These results demonstrate that BIP is an easily implemented technique that successfully confirmed cortical connectivity patterns predicted in the literature, and has the potential to provide new insights regarding the architecture of the brain. [ABSTRACT FROM AUTHOR]

Objective: To quantify the test-retest repeatability of mean diffusivity (MD) and fractional anisotropy (FA) derived from diffusion tensor imaging (DTI) tractography in a cohort of paediatric patients with localization-related epilepsy. Methods: 30 patients underwent 2 DTI acquisitions [repetition time/echo time (ms), 7000/90; flip, 90°; b-value, 1000smm-2; voxel (mm), 2×2×2], Two observers used Diffusion Toolkit and TrackVis (www.trackvis.org) to segment and analyse the following tracts: corpus callosum, corticospinal tracts, arcuate fasciculi, inferior longitudinal fasciculi and inferior fronto-occipital fasciculi. Mean MD and mean FA were calculated for each tract. Each observer independently analysed one of the DTI data sets for every patient. Results: Segmentation identified all tracts in all subjects, except the arcuate fasciculus. There was a highly consistent relationship between repeated observations of MD (r = 0.993; p<0.0001) and FA (r= 0.990; p<0.0001). For each tract, coefficients of variation ranged from 0.9% to 2.1% for MD and from 1.5% to 2.8% for FA. The 95% confidence limits (CLs) for change ranged from 2.8% to 6% for MD and from 4.3% to 8.6% for FA. For the arcuate fasciculus, Cohen's κfor agreement between the observers (identifiable vs not identifiable) was 1.0. Conclusion: We quantified the repeatability of two commonly utilized scalar metrics derived from DTI tractography. For an individual patient, changes greater than the repeatability coefficient or 95% CLs for change are unlikely to be related to variability in their measurement. Advances in knowledge: Reproducibility of these metrics will aid in the design of future studies and might one day be used to guide management in patients with epilepsy. [ABSTRACT FROM AUTHOR]

The aim of our study was to analyze the changes of connective tissue sheaths of epi-, peri- and endoneurium of sural nerve during aging. The study was conducted on sural nerve samples of 10 cases aged 9-80 years. The specimens were embedded in paraffin using standard procedures, after which 5-μm-thick cross-sections of nerve trunks were made and stained using Masson's trichrome staining. After morphological analysis of fascicular structure and connective sheaths of the nerve, morphometric analysis was conducted using the software for digital image analysis 'ImageJ'. Each investigated case was analyzed for total neural, epineurial and fascicular cross-section area, mean values of perineurial index, volume density of myelinated axons and of endoneurial content. To test the difference in mean values for statistical significance we used the Student's T-test for small independent sample. The number of fascicles was 5-13, while the majority of the nerves had less than 10 fascicles. Fascicular structure, which included the number of fascicles and epifascicular/fascicular area ratio, did not show significant changes during aging. Perineurial thickness /fascicle size ratio statistically significantly increased in the older investigated group (p<0.05). Myelinated fibres were of smaller diameter, with more irregular form and markedly less frequent in older cases. Quantitative analysis showed statistically significant decrease in volume density of myelinated fibres in the older group. As results of applied investigation methods we found thickening of perineurial sheath of sural nerve during aging, as well as endoneurial fibrosis. Future investigations of age-related changes should focus on analysis of the components of extracellular matrix within perineurium and endoneurium. [ABSTRACT FROM AUTHOR]

Knowledge on the patterns of repetition amongst individuals who develop language deficits in association with right hemisphere lesions (crossed aphasia) is very limited. Available data indicate that repetition in some crossed aphasics experiencing phonological processing deficits is not heavily influenced by lexical-semantic variables lexicality, imageability, and frequency) as is regularly reported in phonologically32 impaired cases with left hemisphere damage. Moreover, in view of the fact that crossed aphasia is rare, information on the role of right cortical areas and white matter tracts underpinning language repetition deficits is scarce. In this study, repetition performance was assessed in two patients with crossed conduction aphasia and striatal/capsular vascular lesions encompassing the right arcuate fasciculus (AF) and inferior frontal37 occipital fasciculus (IFOF), the temporal stem and the white matter underneath the supramarginal gyrus. Both patients showed lexicality effects repeating better words than nonwords, but manipulation of other lexical-semantic variables exerted less influence on repetition performance. Imageability and frequency effects, production of meaning41 based paraphrases during sentence repetition, or better performance on repeating novel sentences than overlearned clichés were hardly ever observed in these two patients. In one patient, diffusion tensor imaging disclosed damage to the right long direct segment of the AF and IFOF with relative sparing of the anterior indirect and posterior segments of the AF, together with fully developed left perisylvian white matter pathways. These findings suggest that striatal/capsular lesions extending into the right AF and IFOF in some individuals with right hemisphere language dominance are associated with atypical repetition patterns which might reflect reduced interactions between phonological and lexical-semantic processes. [ABSTRACT FROM AUTHOR]

Aims Intraventricular conduction defects (IVCDs) can impair prognosis of heart failure (HF), but their specific impact is not well established. This study aimed to analyse the clinical profile and outcomes of HF patients with LBBB, right bundle branch block (RBBB), left anterior fascicular block (LAFB), and no IVCDs. Methods and results Clinical variables and outcomes after a median follow-up of 21 months were analysed in 1762 patients with chronic HF and LBBB (n = 532), RBBB (n = 134), LAFB (n = 154), and no IVCDs (n = 942). LBBB was associated with more marked LV dilation, depressed LVEF, and mitral valve regurgitation. Patients with RBBB presented overt signs of congestive HF and depressed right ventricular motion. The LAFB group presented intermediate clinical characteristics, and patients with no IVCDs were more often women with less enlarged left ventricles and less depressed LVEF. Death occurred in 332 patients (interannual mortality = 10.8%): cardiovascular in 257, extravascular in 61, and of unknown origin in 14 patients. Cardiac death occurred in 230 (pump failure in 171 and sudden death in 59). An adjusted Cox model showed higher risk of cardiac death and pump failure death in the LBBB and RBBB than in the LAFB and the no IVCD groups. Conclusion LBBB and RBBB are associated with different clinical profiles and both are independent predictors of increased risk of cardiac death in patients with HF. A more favourable prognosis was observed in patients with LAFB and in those free of IVCDs. Further research in HF patients with RBBB is warranted. [ABSTRACT FROM AUTHOR]

Abstract: Background: Borderline personality disorder (BPD) often presents during adolescence. Early detection and intervention decreases its subsequent severity. However, little is known about early predictors and biological underpinnings of BPD. The observed abnormal functional connectivity among brain regions in BPD led to studies of white matter, as the neural substrate of connectivity. However, diffusion tensor imaging (DTI) studies in adult BPD have been inconclusive, and, as yet, there are no published DTI studies in borderline adolescents. Methods: We conducted DTI tractography in 38 BPD patients (14-adolescents, 24-adults) and 32 healthy controls (13-adolescents, 19-adults). Results: We found bilateral tract-specific decreased fractional anisotropy (FA) in inferior longitudinal fasciculus (ILF) in BPD adolescents compared to adolescent controls. ILF FA was significantly higher in adolescent controls compared to BPD adolescents, BPD adults and adult controls (Wilks F(3,57) = 3.55, p < 0.02). Follow-up voxelwise TBSS analysis demonstrated lower FA in BPD adolescents compared to adolescent controls also in uncinate and occipitofrontal fasciculi. Discussion: FA generally develops along an inverted U-shape curve, increasing through adolescence, and slowly decreasing in adulthood. Our findings suggest that, in adolescent BPD, this normal developmental “peak” in FA, which is seen in healthy controls, is not achieved. This suggests a possible neural substrate for the previously reported OFC-amygdala disconnect in adults with BPD. It raises the possibility that a white matter tract abnormality in BPD present in adolescence may not be appreciable in adulthood, but a functional abnormality in the coordination among brain regions persists. Our finding represents a possible biological marker to identify those at risk for developing BPD. [Copyright &y& Elsevier]

Abstract: Offspring from families with alcohol dependence (AD) have been shown to exhibit brain morphological alterations that appear to be related to their familial/genetic risk for AD. Greater susceptibility for developing AD may be related to structural underpinnings of behavioral traits that predispose to AD. We examined white matter (WM) integrity in 81 individuals with either a high density of AD in their families (N=44) or without a family history for either alcohol or drug dependence (N=37). Magnetic resonance images were acquired on a Siemens 3 T scanner with fractional anistropy (FA) and the apparent diffusion coefficient (ADC), along with radial diffusivity (RD) and longitudinal (axial) diffusivity calculated for major white matter tracts in both hemispheres. Extensive personal histories of alcohol and drug use were available from longitudinal collection of data allowing for reliable estimates of alcohol and drug exposure. We found that the interaction of personal exposure to alcohol and familial risk for AD predicts reduction in WM integrity for the inferior longitudinal fasciculus (ILF) and the superior longitudinal fasciculus (SLF) in the left hemisphere and the forceps major tract. Only one tract showed a significant difference for exposure alone, the anterior thalamic radiation. [Copyright &y& Elsevier]

The microsurgical anatomy of cerebellar peduncles and their relationships with neighbouring fasciculi were investigated by using a fibre dissection technique. As the dissection progressed, photographs of each progressive layer were obtained and stereoscopic images were created using the 3D anaglyphic method. These findings provided the anatomical basis for a conceptual division of cerebellar peduncles into segments. The middle cerebellar peduncle (MCP) was divided into two segments: cisternal and intracerebellar segments. The inferior cerebellar peduncle (ICP) was divided into three segments: cisternal, ventricular and intracerebellar segments. The superior cerebellar peduncle (SCP) was divided into three segments: intracerebellar, intermediate and intrategmental segments. The fibre dissection technique disclosed a constant course of peduncular fibres inside the white core of the cerebellum. The pontocerebellar fibres of the MCP pass over and laterally to the bundles of the ICP and SCP. The centripetal fibres of the ICP wrap around the radiation of the SCP and the dentate nucleus, directed towards the cortex of the vermis. The centrifugal bundle of the SCP ascends towards the mesencephalon where it sinks passing below the fibres the lateral lemniscus. The knowledge gained by studying the intrinsic anatomy of the cerebellum is useful to accomplish appropriate surgical planning and, ultimately, to understand the repercussions of surgical procedures on the white matter tracts in this region. [ABSTRACT FROM AUTHOR]

The anatomy of the perisylvian component of the superior longitudinal fasciculus (SLF) has recently been reviewed by numerous diffusion tensor imaging tractography (DTI) studies. However, little is known about the exact cortical terminations of this tract. The aim of the present work is to isolate the different subcomponents of this tract with fiber dissection and DTI tractography, and to identify the exact cortical connections. Twelve postmortem human hemispheres (6 right and 6 left) were dissected using the cortex-sparing fiber dissection. In addition, three healthy brains were analyzed using DTI-based tractography software. The different components of the perisylvian SLF were isolated and the fibers were followed until the cortical terminations. Three segments of the perisylvian SLF were identified: (1) anterior segment, connecting the supramarginal gyrus and superior temporal gyrus with the precentral gyrus, (2) posterior segment, connecting the posterior portion of the middle temporal gyrus with the angular gyrus, and (3) long segment of the arcuate fasciculus that connects the middle and inferior temporal gyri with the precentral gyrus and posterior portion of the inferior and middle frontal gyri. In the present study, three different components of the perisylvian SLF were identified. For the first time, our dissections revealed that each component was connected to a specific cortical area within the frontal, parietal and temporal lobes. By accurately depicting not only the trajectory but also cortical connections of this bundle, it is possible to develop new insights into the putative functional role of this tract. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the microstructural alterations of white matter (WM) in Alzheimer's disease (AD) patients with apathy and to observe the relationships with the severity of apathy. Sixty drug-naive subjects took part in this study (30 apathetic and 30 nonapathetic subjects with AD). The loss of integrity in WM was compared in AD patients with and without apathy through measurement of fractional anisotropy (FA) using by tract-based spatial statistics (TBSS). In addition, we explored the correlation pattern between FA values and the severity of apathy in AD patients with apathy. The apathy group had significantly reduced FA values (pcorrected<0.05) in the genu of the corpus callosum compared to the nonapathy group. The severity of apathy was negatively correlated with FA values of the left anterior and posterior cingulum, right superior longitudinal fasciculus, splenium, body and genu of the corpus callosum and bilateral uncinate fasciculusin the apathy group (pcorrected<0.05). This study was the first to explore FA values in whole brain WM in AD patients with apathy. The findings of these microstructural alterations of WM may be the key to the understanding of underlying neurobiological mechanism and clinical significances of apathy in AD. [ABSTRACT FROM AUTHOR]

Abstract: A high-resolution calcareous nannofossil analysis of the Danian/Selandian boundary was conducted at Site 1262 (Walvis Ridge, South Atlantic) to pinpoint the lowest occurrence of fasciculiths and to unravel the evolutionary trends throughout nannofossil Zone NP4. Using quantitative analyses, numerous primary and secondary bioevents were identified, improving the biostratigraphic resolution of this interval. The main events recorded at Site 1262 were also identified at the Zumaia section Global Stratotype Section and Point (GSSP) of the base of the Selandian and at the Qreiya section (Egypt). The lowest occurrence of fasciculiths (represented by the LO of Gomphiolithus magnicordis and Gomphiolithus magnus) was observed in the middle part of Chron C27r, above the LO of Toweius pertusus and prior to the LO of the genus Sphenolithus. The synchroneity of the LO of fasciculiths was also verified at various latitudes, such as DSDP Site 384 (NW Atlantic), ODP Site 761B (Indian Ocean) and DSDP Site 577A (Pacific Ocean). The first and second diversification events (Steurbaut and Sztrákos, 2008), or radiation events (Bernaola et al., 2009), of fasciculiths have been thoroughly discussed and well characterized by a succession of events. The occurrence of the Latest Danian Event (LDE) and several paleoenvironmental changes recognized during this time interval, coupled with an ecological competition with Sphenolithus, appear to be the probable causes of the First and Second Radiations and the fasciculith barren interval between them. The occurrence of new morphostructures and taxa suggests evolutionary trends and a strict link between morphological evolution and paleoclimate. [Copyright &y& Elsevier]

The article presents author's opinion on the terminology and classification of muscle in sports injuries. It mentions that magnetic resonance imaging (MRI) helps in detecting the presence of microscopic sarcomeric, myofibre and fascicle disruption. It discusses the definition of lesion and aetiology .

The inhibition properties and target sites of monoclonal antibodies (mAbs) Elec403, Elec408 and Elec410, generated against Electrophorus electricus acetylcholinesterase (AChE), have been defined previously using biochemical and mutagenesis approaches. Elec403 and Elec410, which bind competitively with each other and with the peptidic toxin inhibitor fasciculin, are directed toward distinctive albeit overlapping epitopes located at the AChE peripheral anionic site, which surrounds the entrance of the active site gorge. Elec408, which is not competitive with the other two mAbs nor fasciculin, targets a second epitope located in the backdoor region, distant from the gorge entrance. To characterize the molecular determinants dictating their binding site specificity, we cloned and sequenced the mAbs; generated antigen-binding fragments (Fab) retaining the parental inhibition properties; and explored their structure-function relationships using complementary x-ray crystallography, homology modeling and flexible docking approaches. Hypermutation of one Elec403 complementarity-determining region suggests occurrence of antigen-driven selection towards recognition of the AChE peripheral site. Comparative analysis of the 1.9Å-resolution structure of Fab408 and of theoretical models of its Fab403 and Fab410 congeners evidences distinctive surface topographies and anisotropic repartitions of charges, consistent with their respective target sites and inhibition properties. Finally, a validated, data-driven docking model of the Fab403-AChE complex suggests a mode of binding at the PAS that fully correlates with the functional data. This comprehensive study documents the molecular peculiarities of Fab403 and Fab410, as the largest peptidic inhibitors directed towards the peripheral site, and those of Fab408, as the first inhibitor directed toward the backdoor region of an AChE and a unique template for the design of new, specific modulators of AChE catalysis. [ABSTRACT FROM AUTHOR]

The article discusses the study on the structural analysis of enzyme acetylcholinesterase (AchE) with the snake toxin fasciculin-II (FAS-ll). It mentions a web page regarding the said study entitled Proteopedia located at www. proteopedia.org. It also states that fasciculation which could lead to death may occur due to suffocation when AchE is inhibited by FAS-II.