Proximal Arm Research Articles

Sequences of a hairpin structure in the 3′-untranslated region mediate regulation of human pulmonary surfactant protein B mRNA stability

The ability of pulmonary surfactant to reduce alveolar surface tension requires adequate expression of surfactant protein B (SP-B). Dexamethasone (DEX, 10(-7) M) increases human SP-B mRNA stability by a mechanism that requires a 126-nt-long segment (the 7.6S region) of the 3'-untranslated region (3'-UTR). The objective of this study was to identify sequences in the 7.6S region that mediate regulation of SP-B mRNA stability. The 7.6S region was found to be sufficient for DEX-mediated stabilization of mRNA. Sequential substitution mutagenesis of the 7.6S region indicates that a 90-nt region is required for DEX-mediated stabilization and maintenance of intrinsic stability. In this region, one 30-nt-long element (002), predicted to form a stem-loop structure, is sufficient for DEX-mediated stabilization of mRNA and intrinsic mRNA stability. Cytosolic proteins specifically bind element 002, and binding activity is unaffected whether proteins are isolated from cells incubated in the absence or presence of DEX. While loop sequences of element 002 have no role in regulation of SP-B mRNA stability, the proximal stem sequences are required for DEX-mediated stabilization and specific binding of proteins. Mutation of the sequences that comprise the proximal or distal arm of the stem negates the destabilizing activity of element 002 on intrinsic SP-B mRNA stability. These results indicate that cytosolic proteins bind a single hairpin structure that mediates intrinsic and hormonal regulation of SP-B mRNA stability via mechanisms that involve sequences of the stems of the hairpin structure.

Impaired crossed facilitation of the corticospinal pathway after cervical spinal cord injury

In uninjured humans, it is well established that voluntary contraction of muscles on one side of the body can facilitate transmission in the contralateral corticospinal pathway. This crossed facilitatory effect may favor interlimb coordination and motor performance. Whether this aspect of corticospinal function is preserved after chronic spinal cord injury (SCI) is unknown. Here, using transcranial magnetic stimulation, we show in patients with chronic cervical SCI (C(5)-C(8)) that the size of motor evoked potentials (MEPs) in a resting intrinsic hand muscle remained unchanged during increasing levels of voluntary contraction with a contralateral distal or proximal arm muscle. In contrast, MEP size in a resting hand muscle was increased during the same motor tasks in healthy control subjects. The magnitude of voluntary electromyography was negatively correlated with MEP size after chronic cervical SCI and positively correlated in healthy control subjects. To examine the mechanisms contributing to MEP crossed facilitation we examined short-interval intracortical inhibition (SICI), interhemispheric inhibition (IHI), and motoneuronal behavior by testing F waves and cervicomedullary MEPs (CMEPs). During strong voluntary contractions SICI was unchanged after cervical SCI and decreased in healthy control subjects compared with rest. F-wave amplitude and persistence and CMEP size remained unchanged after cervical SCI and increased in healthy control subjects compared with rest. In addition, during strong voluntary contractions IHI was unchanged in cervical SCI compared with rest. Our results indicate that GABAergic intracortical circuits, interhemispheric glutamatergic projections between motor cortices, and excitability of index finger motoneurons are neural mechanisms underlying, at least in part, the lack of crossed corticospinal facilitation observed after SCI. Our data point to the spinal motoneurons as a critical site for modulating corticospinal transmission after chronic cervical SCI.

Neurophysiological analysis of the cauda equina in POEMS syndrome

In POEMS syndrome (Crow-Fukase syndrome), the proximal conduction of peripheral nerves innervating leg muscles is difficult to assess using conventional nerve conduction studies (NCSs) when F-waves or H-reflexes are not detectable. Recently, we developed a novel magnetic stimulation method to measure cauda equina conduction time (CECT) using a powerful coil known as a magnetic augmented translumbosacral stimulation coil (MATS coil) [1–3]. This method allows us to investigate CECT even in patients with peripheral neuropathy [3]. In this study, we applied our method to a patient with POEMS syndrome. The patient was a 72-year-old man who was unable to walk 5 months after onset. Neurological findings at 6 months after onset revealed weakness with muscular atrophy (Medical Research Council scale for muscle strength grades: proximal arm 4, distal arm 3, proximal leg 3 and distal leg 1), distal dominant sensory disturbance and areflexia of the extremities. Whole-body computed tomography revealed hepatomegaly and multiple enlarge lymph nodes. We made the diagnosis of POEMS syndrome on the basis of skin hemangioma, skin pigmentation, hirsutism, leg edema, hepatomegaly, lymphadenopathy, monoclonal protein of immunoglobulin G (k type), and subacute motor and sensory polyneuropathy. Conventional NCSs were performed on the right side. In the median nerve, the amplitude of compound muscle action potentials (CMAPs) was severely reduced to 0.4 mV. Neither a pathological temporal dispersion nor a conduction block was detected. Motor conduction velocity (MCV) between wrist and elbow was slowed to 24 m/s with prolonged distal latency (5.6 ms). Sensory nerve action potentials (SNAPs) were not evoked. For the lower extremities, neither CMAPs in the tibial nerve nor SNAPs in the sural nerve were evoked. Additionally, neither F-waves in the median and tibial nerves nor H-reflexes in the tibial nerve were evoked. Needle electromyography (nEMG) was performed in the biceps brachii, first dorsal interossei, rectus femoris, and tibialis anterior muscles on the right side. Abundant spontaneous activities were recorded during relaxation in only the first dorsal interossei and tibialis anterior muscles. In all the contracted muscles, recruitment of motor unit potentials was reduced during voluntary contraction (contraction of the tibialis anterior muscle was impossible). MATS coil stimulation was performed to measure CECT. CMAPs were recorded from the biceps femoris muscle. This particular proximal muscle was selected since it had experienced much less atrophy than the distal muscles. The most distal part of the cauda equina was activated by MATS coil stimulation over the first sacral spinous processes (S1) [1–3]. The most proximal part of the cauda equina was activated by MATS coil stimulation over the first lumbar spinous processes (L1) [2, 3]. As shown in Fig. 1b, this method demonstrated severely prolonged CECT (right 8.1 ms, left 8.0 ms; normal values H. Matsumoto (&) H. Hashida Department of Neurology, Japanese Red Cross Medical Center, 4-1-22 Hiroo, Shibuya-ku, Tokyo150-8935, Japan e-mail: hideyukimatsumoto.jp@gmail.com

Glenohumeral tuberculous arthritis complicated with beta haemolytic streptococcus: An extraordinary rare association: A case report

INTRODUCTIONSeptic arthritis of the glenohumeral joint is a rare entity and its diagnosis is difficult with a superadded infection in the presence of underlying tuberculosis. We report the first case of group B beta haemolytic streptococcal glenohumeral arthritis with underlying tuberculosis. CASE PRESENTATIONA 40 year old lady previously diagnosed to have poliomyelitis, rheumatoid arthritis, hepatitis C, and diabetes mellitus for the last 10 years, presented to the emergency room with diabetic ketoacidosis. Two weeks prior to presentation she developed fever along with pain and swelling in left shoulder with uncontrolled blood sugars. Local examination of the shoulder revealed global swelling with significant restricted range of motion. MRI showed a large multiloculated collection around the left shoulder joint extending into the axilla, and proximal arm. Urgent arthrotomy performed and about 120ml thick pus was drained. The patient was started on clindamicin and antituberculous chemotherapy and her symptoms dramatically improved. DISCUSSIONBone and joint involvement accounts for approximately 2% of all reported cases of tuberculosis (TB), and it accounts for approximately 10% of the extra pulmonary cases of TB. Tuberculosis of the shoulder joint constitutes 1–10.5% of skeletal tuberculosis. Classical symptoms of fever, night sweats, and weight loss may be absent, and a concurrent pulmonary focus may not be evident in most cases. CONCLUSIONDespite acute presentation of septic arthritis, in areas endemic for tuberculosis and particularly in an immunocompromised patient, workup for tuberculosis should be part of the routine evaluation.

Maladaptive plasticity for motor recovery after stroke: mechanisms and approaches.

Many studies in human and animal models have shown that neural plasticity compensates for the loss of motor function after stroke. However, neural plasticity concerning compensatory movement, activated ipsilateral motor projections and competitive interaction after stroke contributes to maladaptive plasticity, which negatively affects motor recovery. Compensatory movement on the less-affected side helps to perform self-sustaining activity but also creates an inappropriate movement pattern and ultimately limits the normal motor pattern. The activated ipsilateral motor projections after stroke are unable to sufficiently support the disruption of the corticospinal motor projections and induce the abnormal movement linked to poor motor ability. The competitive interaction between both hemispheres induces abnormal interhemispheric inhibition that weakens motor function in stroke patients. Moreover, widespread disinhibition increases the risk of competitive interaction between the hand and the proximal arm, which results in an incomplete motor recovery. To minimize this maladaptive plasticity, rehabilitation programs should be selected according to the motor impairment of stroke patients. Noninvasive brain stimulation might also be useful for correcting maladaptive plasticity after stroke. Here, we review the underlying mechanisms of maladaptive plasticity after stroke and propose rehabilitation approaches for appropriate cortical reorganization.

Prader-Willi Syndrome: Clinical Aspects

Prader-Willi Syndrome (PWS) is a complex multisystem genetic disorder that shows great variability, with changing clinical features during a patient's life. The syndrome is due to the loss of expression of several genes encoded on the proximal long arm of chromosome 15 (15q11.2–q13). The complex phenotype is most probably caused by a hypothalamic dysfunction that is responsible for hormonal dysfunctions and for absence of the sense of satiety. For this reason a Prader-Willi (PW) child develops hyperphagia during the initial stage of infancy that can lead to obesity and its complications. During infancy many PW child display a range of behavioural problems that become more noticeable in adolescence and adulthood and interfere mostly with quality of life. Early diagnosis of PWS is important for effective long-term management, and a precocious multidisciplinary approach is fundamental to improve quality of life, prevent complications, and prolong life expectancy.

A three-dimensional topology of complex I inferred from evolutionary correlations

BackgroundThe quaternary structure of eukaryotic NADH:ubiquinone oxidoreductase (complex I), the largest complex of the oxidative phosphorylation, is still mostly unresolved. Furthermore, it is unknown where transiently bound assembly factors interact with complex I. We therefore asked whether the evolution of complex I contains information about its 3D topology and the binding positions of its assembly factors. We approached these questions by correlating the evolutionary rates of eukaryotic complex I subunits using the mirror-tree method and mapping the results into a 3D representation by multidimensional scaling.ResultsMore than 60% of the evolutionary correlation among the conserved seven subunits of the complex I matrix arm can be explained by the physical distance between the subunits. The three-dimensional evolutionary model of the eukaryotic conserved matrix arm has a striking similarity to the matrix arm quaternary structure in the bacterium Thermus thermophilus (rmsd=19 Å) and supports the previous finding that in eukaryotes the N-module is turned relative to the Q-module when compared to bacteria. By contrast, the evolutionary rates contained little information about the structure of the membrane arm. A large evolutionary model of 45 subunits and assembly factors allows to predict subunit positions and interactions (rmsd = 52.6 Å). The model supports an interaction of NDUFAF3, C8orf38 and C2orf56 during the assembly of the proximal matrix arm and the membrane arm. The model further suggests a tight relationship between the assembly factor NUBPL and NDUFA2, which both have been linked to iron-sulfur cluster assembly, as well as between NDUFA12 and its paralog, the assembly factor NDUFAF2.ConclusionsThe physical distance between subunits of complex I is a major correlate of the rate of protein evolution in the complex I matrix arm and is sufficient to infer parts of the complex’s structure with high accuracy. The resulting evolutionary model predicts the positions of a number of subunits and assembly factors.

Cytogenetics of hepatoblastoma

The cytogenetics of hepatoblastoma demonstrate recurring events which include whole chromosome trisomies, most commonly trisomy of chromosome 2, 8, or 10. In addition, unbalanced translocations involving a breakpoint on the proximal short arm of chromosome 1 are observed which result in a duplication of the long arm of chromosome 1q. The most commonly involved reciprocal chromosomal arm is 4q, although the reciprocal chromosome is highly variable and always results in a loss of chromosomal material. The full significance of these chromosomal changes has yet to be confirmed in large studies, however a suggestion of an association of duplication of regions of 2q with a poor prognosis. A rare sub-type of hepatoblastoma, known as the small cell undifferentiated variant, is associated with deletion or translocation of 22q, the locus of the rhabdoid tumor gene, SMARCB1.

Functional assessment of proximal arm muscles by target-reaching movements in patients with cervical myelopathy

Functional assessment of proximal arm muscles by target-reaching movements in patients with cervical myelopathy

Managing Severe Upper Extremity Ischemia from Mobile Aortic Arch Thrombus: A Novel Approach Using Isolated Limb Perfusion with Tissue Plasminogen Activator

Etiologies of upper extremity ischemia are numerous and include embolic aortic pathology. Traditional operative management for this entity includes open thrombectomy, catheter directed thrombolysis and/or percutaneous mechanical thrombectomy. These conventional options, however, may not be ideal for patients having unstable aortic arch thrombus and profound distal arterial thrombosis of the hand. An alternative approach for such patients is isolated limb perfusion (ILP) with tissue plasminogen activator (tPA). A 37-year-old female presented with sudden onset acute left hand ischemia associated with sensory and motor deficits. An axillary pulse was present and distal pulses were absent as were radial, ulnar and palmar signals. Her medical history was unremarkable but she was a 1 pack/day smoker. Her evaluation included a chest CT-angiogram showing a pedunculated aortic arch thrombus that was confirmed on transthoracic echocardiogram (TTE) and was mobile (Fig 1). Her hand ischemia was presumed to be caused by an embolus originating from the aortic arch. Given the severity of distal forearm and hand ischemia with the presence of mobile aortic thrombus, catheter directed thrombolysis was felt to be contraindicated and the patient was taken to the operating room (OR) for emergent brachial, radial and ulnar thrombectomy. This yielded some thrombus; however, an intraoperative angiogram (Fig 2, A) post-thrombectomy still showed significant residual hand thrombus with absent radial, ulnar and palmar signals. Further thrombectomy was felt to be ineffective and ILP with tPA was felt to be most appropriate. A perfusion circuit was constructed and connected to the patient via brachial artery and vein cannulas. A proximal arm tourniquet was placed. The perfusate was charged with 25 mg tPA/hour for a total circulation time of 2 hours at a flow rate of 200 cc/min. Fibrinogen levels remain unchanged during perfusion. After completing perfusion, a repeat angiogram (Fig 2, B) was performed showing marked thrombus resolution. The cannula sites and incision were closed. The patient then underwent left postero-lateral thoracotomy and open aortic thrombectomy without cardiopulmonary bypass. At 6 months follow-up, radial and ulnar pulses are present and without sensory or motor hand deficits. Prompt open surgical thrombectomy remains first line therapy for cases of acute severe upper extremity ischemia due to thromboembolism although it may be ineffective for distal arterial bed thrombus. Alternatively, catheter-directed thrombolysis is effective for distal bed thrombus. However, this is precluded in advanced ischemia and when systemic tPA exposure is contraindicated due to risk of further embolization from proximal thrombus. ILP with tPA allows for rapid distal bed thrombolysis while theoretically limiting systemic exposure. In circumstances where perfusion circuits are readily available, it is possible to utilize ILP with tPA as an alternative strategy when conventional treatment methods are deemed to be suboptimal.

Human hand function: the limitations of brain and brawn

Human hand function: the limitations of brain and brawn

Effects of a robot-assisted training of grasp and pronation/supination in chronic stroke: a pilot study

BackgroundRehabilitation of hand function is challenging, and only few studies have investigated robot-assisted rehabilitation focusing on distal joints of the upper limb. This paper investigates the feasibility of using the HapticKnob, a table-top end-effector device, for robot-assisted rehabilitation of grasping and forearm pronation/supination, two important functions for activities of daily living involving the hand, and which are often impaired in chronic stroke patients. It evaluates the effectiveness of this device for improving hand function and the transfer of improvement to arm function.MethodsA single group of fifteen chronic stroke patients with impaired arm and hand functions (Fugl-Meyer motor assessment scale (FM) 10-45/66) participated in a 6-week 3-hours/week rehabilitation program with the HapticKnob. Outcome measures consisted primarily of the FM and Motricity Index (MI) and their respective subsections related to distal and proximal arm function, and were assessed at the beginning, end of treatment and in a 6-weeks follow-up.ResultsThirteen subjects successfully completed robot-assisted therapy, with significantly improved hand and arm motor functions, demonstrated by an average 3.00 points increase on the FM and 4.55 on the MI at the completion of the therapy (4.85 FM and 6.84 MI six weeks post-therapy). Improvements were observed both in distal and proximal components of the clinical scales at the completion of the study (2.00 FM wrist/hand, 2.55 FM shoulder/elbow, 2.23 MI hand and 4.23 MI shoulder/elbow). In addition, improvements in hand function were observed, as measured by the Motor Assessment Scale, grip force, and a decrease in arm muscle spasticity. These results were confirmed by motion data collected by the robot.ConclusionsThe results of this study show the feasibility of this robot-assisted therapy with patients presenting a large range of impairment levels. A significant homogeneous improvement in both hand and arm function was observed, which was maintained 6 weeks after end of the therapy.

Optical Transport Properties along the Pericardium Meridian under Different Pressure

Introduction: This study seeks to discuss the light wave transport characteristics variation along the pericardium Meridian under different pressures. Methods: We selected 36 healthy students at the school for this study, tied up the desktop blood pressure cuff onto subjects’right proximal arms, fixed the detection probe immovably on the Neiguan (PC6) acupoint and the reference point which was 1cm off the PC6, and collected the light signal along the meridian and non-meridian when the laser irradiate Jianshi(PC5), Ximen(PC4) and the corresponding reference points respectively under pressure of 0, 100, 130 and 160. Results: The differences in optical transport properties between meridian and nonmeridian were significant: under the same pressures(0s, 100s,130s, and 160mmHg), the relative attenuation rate of optical signal at the same distance between meridian and non-meridian were significant(p 0.05). Under four different pressure situations, the optical signal at acupoint(PC5) and non-acupoint(NP) along the meridian were significantly different with the corresponding reference points along the non-meridian(P<0.001); the optical signal on the meridian is stronger than the non-meridian one; the optical signals are strikingly different at acupoints, non-acupoints, and reference points between and 100, 130, and 160mmHg pressures (P≤0.001); however, no difference was found between 100, 130, and 160mmHg pressures. Conclusion: The optical signal on the meridian is stronger than the non-meridian. The optical signal attenuates slower when it transported along meridians. The human meridians may be the good pathway for light waves with certain wavelengths. That is to say light waves with certain wavelengths can transport and be blocked along meridian direction, when it irritates the meridians, or acupoints after excluding the influence of human anatomy structure, which verified again the objective existence of meridians transporting and the possibility of blocking from the optical view.

Optical Transport Properties along the Pericardium Meridian under Different Pressure

Introduction: This study seeks to discuss the light wave transport characteristics variation along the pericardium Meridian under different pressures. Methods: We selected 36 healthy students at the school for this study, tied up the desktop blood pressure cuff onto subjects’right proximal arms, fixed the detection probe immovably on the Neiguan (PC6) acupoint and the reference point which was 1cm off the PC6, and collected the light signal along the meridian and non-meridian when the laser irradiate Jianshi(PC5), Ximen(PC4) and the corresponding reference points respectively under pressure of 0, 100, 130 and 160. Results: The differences in optical transport properties between meridian and nonmeridian were significant: under the same pressures(0s, 100s,130s, and 160mmHg), the relative attenuation rate of optical signal at the same distance between meridian and non-meridian were significant(p 0.05). Under four different pressure situations, the optical signal at acupoint(PC5) and non-acupoint(NP) along the meridian were significantly different with the corresponding reference points along the non-meridian(P<0.001); the optical signal on the meridian is stronger than the non-meridian one; the optical signals are strikingly different at acupoints, non-acupoints, and reference points between and 100, 130, and 160mmHg pressures (P≤0.001); however, no difference was found between 100, 130, and 160mmHg pressures. Conclusion: The optical signal on the meridian is stronger than the non-meridian. The optical signal attenuates slower when it transported along meridians. The human meridians may be the good pathway for light waves with certain wavelengths. That is to say light waves with certain wavelengths can transport and be blocked along meridian direction, when it irritates the meridians, or acupoints after excluding the influence of human anatomy structure, which verified again the objective existence of meridians transporting and the possibility of blocking from the optical view.

West syndrome associated with mosaic duplication of FOXG1 in a patient with maternal uniparental disomy of chromosome 14

FOXG1 on chromosome 14 has recently been suggested as a dosage-sensitive gene. Duplication of this gene could cause severe epilepsy and developmental delay, including infantile spasms. Here, we report on a female patient diagnosed with maternal uniparental disomy of chromosome 14 and West syndrome who carried a small supernumerary marker chromosome. A chromosomal analysis revealed mosaicism of 47,XX, + mar[8]/46,XX[18]. Spectral karyotyping multicolor fluorescence in situ hybridization analysis confirmed that the marker chromosome was derived from chromosome 14. A DNA methylation test at MEG3 in 14q32.2 and microsatellite analysis using polymorphic markers on chromosome 14 confirmed that the patient had maternal uniparental disomy 14 as well as a mosaic small marker chromosome of paternal origin containing the proximal long arm of chromosome 14. Microarray-based comparative genomic hybridization analysis conclusively defined the region of the gain of genomic copy numbers at 14q11.2-q12, encompassing FOXG1. The results of the analyses of our patient provide further evidence that not only duplication but also a small increase in the dosage of FOXG1 could cause infantile spasms.

Lateral arm plate morphology in brittle stars (Echinodermata: Ophiuroidea): new perspectives for ophiuroid micropalaeontology and classification

Lateral arm plates, the spine-bearing plates of the ophiuroid arm skeleton, have long been assumed to display sufficient morphological diversity to be used for species identifications in ophiuroid micropalaeontology. As a consequence, many new brittle-star species have been described on the basis of isolated fossil lateral arm plates. A substantial lack of information on the morphological variability of lateral arm plates in respect of taxon concepts, however, has led to increasing confusion over species limits and excessive extensions of stratigraphic species ranges. In this study, we therefore performed a detailed assessment of the variability of lateral arm plate morphology within and between species in order to test to what extent isolated lateral arm plates can be used for species identifications. To this end, we investigated the morphological variability of lateral arm plates within species according to ontogenetic changes and according to the position of the plates along the arm. Furthermore, we examined the lateral arm plates of 56 Recent species, belonging to 27 genera and 10 families, and systematically assessed their morphology in the light of currently accepted taxon concepts. The results of this study demonstrate that lateral arm plate morphology is in accordance with most family, genus and species limits. Some of the currently accepted taxon concepts, including the affinities between the Ophiacanthidae and Ophiocomidae, however, are challenged by lateral arm plate morphology. Differences in lateral arm plate morphology between taxa are the most conspicuously displayed by adult proximal lateral arm plates, as a consequence of their high degree of differentiation compared to distal or juvenile lateral arm plates. Differences at species level, often pertain to characters which were considered to be within-species variation in previous micropalaeontological works, suggests that species identifications based on isolated fossil lateral arm plates require a much more detailed and careful morphological assessment. Some of the species studied herein displayed indistinguishable lateral arm plate morphologies, but belonged to the same genus in all cases. Our study endorses the use of isolated fossil lateral arm plates for taxonomic interpretations in ophiuroid micropalaeontology, including species identifications and the creation of new taxa, providing that descriptions are based on pristinely preserved adult proximal LAPs, described and illustrated using SEM-pictures of both the external and internal sides of the plate.

Shoulder Pain in Amyotrophic Lateral Sclerosis

To determine the frequency of shoulder pain in our amyotrophic lateral sclerosis (ALS) population and to explore potential associations with demographic and clinical features. We retrospectively reviewed the medical records of 193 patients with ALS patients seen at the Lahey Clinic between 2005 and 2009. Patients were categorized by the predominance of upper and lower motor neuron signs and the body regions initially involved. The frequency of shoulder pain was identified in each of these subgroups. Forty-five (23%) of the 193 patients reported shoulder pain at some time during the course of their illness. Age, gender, manual labor, prior shoulder problems, ALS phenotype, and initial region of involvement were not correlated with shoulder pain. Patients with shoulder pain were more likely to develop proximal arm weakness during their illness and to report pain elsewhere. Despite the limitations posed by this retrospective study, it underscores the prevalence of shoulder pain in patients with ALS. Further studies to identify risk factors, mechanisms of, and treatments for shoulder pain in patients with ALS may benefit this population.

A new case of rare proximal 3q13 interstitial deletion

Abstract We present the case of a 20-year-old man referred to the clinical geneticist because of mental retardation and dysmorphic features because of concerns about hereditability when his older, healthy brother was expecting a child. Deletion of proximal 3q arm was found with standard G-banding, and array comparative genomic hybridisation (array-CGH) was used to further locate the breakpoints. A unique interstitial deletion del 3q13.11q13.33 was confirmed. The first clinical symptoms in the 20-year-old were described at the age of 4 months when the pediatrician reported muscle hypertonia of the lower limbs, which later evolved into hypotonia. Later clinical observations revealed that the patient’s psychomotor development was delayed: he exhibited craniofacial abnormalities, cryptorchidism, thoracic kyphosis, and tapering fingers. Interstitial deletions of the proximal long arm of chromosome 3 have rarely been reported:; there are only 12 previously reported cases. The breakpoints and sizes of described deletions vary greatly, which makes definite genotype-phenotype conclusions impossible at this time. Developmental delay is one of the common features described in the majority of reported cases. The BTB-zinc finger gene ZBTB20 might be a potential candidate gene: it was shown in the mouse hippocampus to be expressed during the important period of neurogenesis of pyramidal neurons. Also, four of patients reported to date had agenesis of the corpus callosum and one, holoprosencephaly. We suggest that the GAP43 gene is involved in the development of structural neurological abnormalities in patients with 3q deletion.

Quadrupedal coordination of bipedal gait: implications for movement disorders

During recent years, evidence has come up that bipedal locomotion is based on a quadrupedal limb coordination. A task-dependent neuronal coupling of upper and lower limbs allows one to involve the arms during gait but to uncouple this connection during voluntarily guided arm/hand movements. Hence, despite the evolution of a strong cortico-spinal control of hand/arm movements in humans, a quadrupedal limb coordination persists during locomotion. This has consequences for the limb coordination in movement disorders such as in Parkinson's disease (PD) and after stroke. In patients suffering PD, the quadrupedal coordination of gait is basically preserved. The activation of upper limb muscles during locomotion is strong, similar as in age-matched healthy subjects although arm swing is reduced. This suggests a contribution of biomechanical constraints to immobility. In post-stroke subjects a close interactions between unaffected and affected sides with an impaired processing of afferent input takes place. An afferent volley applied to a leg nerve of the unaffected leg leads to a normal reflex activation of proximal arm muscles of both sides. In contrast, when the nerve of the affected leg was stimulated, neither on the affected nor in the unaffected arm muscles EMG responses appear. Muscle activation on the affected arm becomes normalized by influences of the unaffected side during locomotion. These observations have consequences for the rehabilitation of patients suffering movement disorders.

A large new species of the genus Ptilocrinus (Echinodermata, Crinoidea, Hyocrinidae) from Antarctic seamounts

Ptilocrinus amezianeae n. sp. is a new species of stalked crinoid attributed to the family Hyocrinidae. Forty-five specimens were collected from seamounts north of the Ross Sea, and one specimen from the Kerguelen Plateau at depths ranging from 450 to 1,680 m. The collection from Admiralty and Scott seamounts constitutes the first example of a hyocrinid population known both from in situ photographs and from numerous collected specimens ranging from small juvenile to large adult. Variation in theca and stalk articulation characters throughout ontogeny is congruent with the molecular data and indicates that all the specimens examined belong to a single species. Tegmen and pinnule architecture, brachial arrangement, and stalk articular facets indicate that Ptilocrinus amezianeae n. sp. has close affinities with P. clarki and P. pinnatus from the northeastern Pacific and displays the most derived characters among these three species. Two cases of true arm division into two unequal branches suggest that Ptilocrinus and Calamocrinus are closely related. The picture and video transects on Admiralty seamount show a patchy distribution of living specimens with patches of mean density ca. 2.6 individuals m-2. In situ photographs also document predation by a sea urchin and a sea star on tegmen and proximal arms. The COI gene sequences analyzed in 25 specimens from Admiralty and Scott seamounts display low pairwise distances, low nucleotidic diversity, and intermediate haplotype diversity. These results, together with disarticulated ossicles and attachment disks observed on in situ photographs, indicate that the population investigated here is in decline.