A new genus of Herpyllobiidae (Copepoda: Cyclopoida) from a deep-living annelid (Polychaeta: Sigalionidae).

A taxonomic study of deep-sea polychaetes collected at a depth of 2,805 m off the northern coast of California revealed a scaleworm of the family Sigalionidae with an attached parasitic copepod. The copepod represents an undescribed genus of the family Herpyllobiidae, comprising mesoparasitic copepods chiefly recorded from polychaetes of the family Polynoidae. Blakerius gen. nov. diverges from the other herpyllobiid genera by its possession of 1) a chalice-shaped ectosoma with several protuberances along the posterior margin and a long cylindrical shaft with a hyaline coating and integumental sculpturing, a short stalk with a small, anteriorly placed sclerotized ring, 2) a relatively large, discoid-shaped endosoma with digitiform process, and 3) attached male copepodids with 3-segmented antennules, containing limbless sac-like males. The new genus is compared with other herpyllobiids. This discovery increases the number of known herpyllobiid genera to six and is the first record of a herpyllobiid parasitizing a sigalionid polychaete.urn: lsid: zoobank.org:pub:5E31FEED-D3EB-460E-AEA4-02A9D3A778D6.

Small worms of Sthenelanellinae, Pholoinae and Pisioninae (Annelida, Sigalionidae) from the Tropical Northwestern Atlantic.

The family Sigalionidae is characterized, among other features, by including scale worms with large bodies. However, among sigalionids, the subfamilies Sthenelanellinae, Pholoinae, and Pisioninae stand out by their small representatives with few segments and fragile bodies. In the Tropical Northwestern Atlantic, which includes part of the Gulf of Mexico and the Caribbean Sea, these subfamilies have been rarely studied, with few species recorded, and questionable records. This contribution aims to improve the knowledge of sthenelanellins, pholoins, and pisionins in the region through a faunistic study based on material from two Mexican scientific collections: the Reference Collection of Laboratorio de Biodiversidad y Cambio Climático (BIOMARCCA) and the Reference Collection of Benthos (ECOSUR) of El Colegio de la Frontera Sur. Pisione wolfi is confirmed from the Tropical Northwestern Atlantic, and three new species are described: Sthenelanella pechi sp. nov., S. sarae sp. nov. and Taylorpholoe anabelae sp. nov. A key to all Sthenelanella and Taylorpholoe species is also included.

An Exploratory Survey on the Care for Ataxic Patients in the American Continents and the Caribbean.

Little is known about access of rare disease carriers to health care. To increase this knowledge, the Pan American Hereditary Ataxia Network (PAHAN) conducted an exploratory survey about care for hereditary ataxias in American continents and the Caribbean. A questionnaire was sent to health professionals about the hereditary ataxias identified; access to care; and local teaching and research. The number of ataxics under current care per 100,000 inhabitants was subtracted from the expected overall prevalence of 6/100,000, to estimate the prevalence of uncovered ataxic patients. Local Human Development Indexes (HDI) were used to measure socio-economic factors. Twenty-six sites participated. Twelve sites had very high, 13 had high, and one site had medium HDI. Participants reported on 2239 and 602 patients with spinocerebellar ataxias and recessive forms under current care. The number of patients under current care per inhabitants varied between 0.14 and 12/100,000. The estimated prevalence of uncovered ataxic patients was inversely proportional to HDIs (rho = 0.665, p = 0.003). Access to diagnosis, pre-symptomatic tests, and rehabilitation were associated with HDIs. More and better molecular diagnostic tools, protocols and guidelines, and professional training for ataxia care were the top priorities common to all respondents. Evidence of inequalities was confirmed. Lower HDIs were associated with high potential numbers of uncovered ataxic subjects, and with lack of molecular diagnosis, pre-symptomatic testing, and rehabilitation. More and better diagnostic tools, guidelines, and professional training were priorities to all sites. PAHAN consortium might help with the last two tasks.

Prodromal Spinocerebellar Ataxia Type 2 Subjects Have Quantifiable Gait and Postural Sway Deficits.

BACKGROUND: The search for valid preclinical biomarkers of cerebellar dysfunction is a key research goal for the upcoming era of early interventional approaches in spinocerebellar ataxias. This study aims to describe novel preclinical biomarkers of subtle gait and postural sway abnormalities in prodromal spinocerebellar ataxia type 2 (pre-SCA2). METHODS: Thirty pre-SCA2 patients and their matched healthy controls underwent quantitative assessments of gait and postural sway using a wearable sensor-based system and semiquantitative evaluation of cerebellar features by SARA (Scale for the Assessment and Rating of Ataxia) score. RESULTS: Quantitative analysis of natural gait showed a significantly larger variability of the swing period, toe-off angle and toe-out angle in pre-SCA2, and larger mean coronal and transverse ranges of motion of the trunk at the lumbar location and of the sagittal range of motion of the trunk at the sternum location compared to controls. During tandem gait, pre-SCA2 subjects showed larger lumbar, trunk, and arm ranges of motion than controls. Postural sway analysis showed excessive body oscillation that was increased in tandem stance. Overall, these abnormalities were detected in pre-SCA2 patients without clinical evidence of abnormalities in SARA. The toe-off angle and swing time variability were significantly correlated with the time to ataxia onset, whereas the toe-off angle and transverse range of motion at trunk position during tandem gait were significantly associated with the SARA score. CONCLUSIONS: This study demonstrates early alteration of gait and postural sway control in prodromal SCA2 using a wearable sensor-based system. This offers new pathophysiological hints into this early disease stage and provides novel potential biomarkers for future clinical trials. © 2020 International Parkinson and Movement Disorder Society.

Founder Effects of Spinocerebellar Ataxias in the American Continents and the Caribbean.

Spinocerebellar ataxias (SCAs) comprise a heterogeneous group of autosomal dominant disorders. The relative frequency of the different SCA subtypes varies broadly among different geographical and ethnic groups as result of genetic drifts. This review aims to provide an update regarding SCA founders in the American continents and the Caribbean as well as to discuss characteristics of these populations. Clusters of SCAs were detected in Eastern regions of Cuba for SCA2, in South Brazil for SCA3/MJD, and in Southeast regions of Mexico for SCA7. Prevalence rates were obtained and reached 154 (municipality of Báguano, Cuba), 166 (General Câmara, Brazil), and 423 (Tlaltetela, Mexico) patients/100,000 for SCA2, SCA3/MJD, and SCA7, respectively. In contrast, the scattered families with spinocerebellar ataxia type 10 (SCA10) reported all over North and South Americas have been associated to a common Native American ancestry that may have risen in East Asia and migrated to Americas 10,000 to 20,000 years ago. The comprehensive review showed that for each of these SCAs corresponded at least the development of one study group with a large production of scientific evidence often generalizable to all carriers of these conditions. Clusters of SCA populations in the American continents and the Caribbean provide unusual opportunity to gain insights into clinical and genetic characteristics of these disorders. Furthermore, the presence of large populations of patients living close to study centers can favor the development of meaningful clinical trials, which will impact on therapies and on quality of life of SCA carriers worldwide.

New records of polychaetes (Annelida: Polychaeta) from three locations of Oaxaca, Mexico

Introduction: The knowledge of polychaetes from Oaxaca, Mexico, is represented by 41 families and 241 species, nevertheless, 148 species are considered questionable. The majority of taxonomic studies of polychaetes in Oaxaca have taken placed on estuarine zones or commercial ports, sidelining other marine ecosystems. Objective: To identify the polychaeta-fauna from three different marine ecosystems in Oaxaca, Mexico. Methods: Specimens analyzed came from the Sección de poliquetos de la Colección Científica at the Laboratorio de Sistemática de Invertebrados Marinos, Universidad del Mar. The material deposited in the collection was collected between 2007-2017; additionally, new collect were realized in 2017. For each locality, the family and species richness were estimated using the accumulation function of linear dependence model. Results: One hundred lots and 273 specimens were revised. Seventy-one taxa, belonging to 47 genera and 21 families were identified, only twenty of these taxa are confirmed species (28 %). Chacahua Lagoon had the highest richness and relative abundance with 37 taxa and 149 specimens, Agua Blanca was identified 21 taxa and 92 specimens, and from San Agustín 19 taxa and 32 specimens. Sabellariidae had the highest relative abundance (58 specimens), while Phyllodocidae presented the highest species richness (12 species). Conclusions: This study adds 75 new records of taxa of polychaetes to the coast Oaxaca, which increase the knowledge in this animal group, now represented by 304 species, belonging to 154 genera and 42 families.

Introducción: El conocimiento de poliquetos en Oaxaca, México, está representado por 41 familias y 241 especies, sin embargo, 148 especies son consideradas cuestionables. La mayoría de los estudios taxonómicos de poliquetos en Oaxaca se han enfocado en zonas estuarinas o puertos comerciales, dejando de lado otros ecosistemas marinos. Objetivo: Identificar la poliqueto-fauna de tres ecosistemas diferentes de Oaxaca. Métodos: Los especímenes analizados pertenecen a la Sección de poliquetos de la Colección Científica del Laboratorio de Sistemática de Invertebrados Marinos, Universidad del Mar. El material depositado en la colección fue colectado entre 2007-2017; adicionalmente, se realizaron nuevas colectas en 2017. Para cada localidad, la riqueza de especies y familias fue estimada utilizando la función de acumulación del modelo de dependencia lineal. Resultados: Se revisaron 100 lotes y 273 especímenes. Se identificaron 71 taxones, pertenecientes a 47 géneros y 21 familias, solo 20 de estos taxones corresponden a nombres específicos (28 %). La Laguna de Chacahua presentó la mayor riqueza y abundancia relativa con 37 taxones y 149 especímenes, en Agua Blanca se identificaron 21 taxones y 92 especímenes, y para San Agustín 19 taxones y 32 especímenes. La familia Sabellariidae tuvo la mayor abundancia relativa (58 especímenes), mientras que Phyllodocidae presentó la mayor riqueza de especies (12 especies). Conclusiones: Con este estudio se añaden 75 nuevos registros de poliquetos para la costa de Oaxaca, incrementando el conocimiento de este grupo, ahora representado por 304 especies pertenecientes a 154 géneros y 42 familias.

Chrysopetalids (Phyllodocida: Chrysopetalidae) from the southern Mexican Pacific, including a new species.

The family Chrysopetalidae has been poorly studied from the Pacific coast of Mexico compared to other families. Specifically from the southern Mexican Pacific, only two species of the family have been recorded in previous studies, Chrysopetalum occidentale and Paleanotus chrysolepis. In this study 311 specimens were revised, and nine species, belonging to six genera were found. Eight of these species are new records from the southern Mexican Pacific coast: Arichlidon watsonae n. sp., Bhawania cf. goodei, Chrysopetalum elegantoides, C. maculata, Hyalopale sp., Paleaequor psamathe, Paleanotus bellis and P. purpurea. A new species is also described, Arichlidon watsonae n. sp., which is characterized by the curved tips blades of the falcigers and their small and ovoid palps. Additionally, the genera Arichlidon and Hyalopale are recorded by first time from the Tropical Eastern Pacific.

New records of benthic hydroids (Cnidaria: Hydrozoa) from the coast of Oaxaca, Mexico.

Hydroids of the Pacific coast of Mexico have been little studied. For the coast of Oaxaca, only five papers provide information on species of the region, with some records included in those publications being questionable. Seven species, Pennaria disticha, Clytia linearis, Clytia cf. gracilis, Obelia dichotoma, Ventromma halecioides, Dynamena crisioides and Tridentata turbinata, were discovered during the study and are reported herein. Of these species, Pennaria disticha and Tridentata turbinata are new records for the Mexican Pacific coast, and Clytia linearis and Ventromma halecioides are new records for Oaxaca. Geographic ranges of other hydroids, recorded in earlier studies, are expanded.

Decoding pathogenesis of slow-channel congenital myasthenic syndromes using recombinant expression and mice models.

Despite the fact that they are orphan diseases, congenital myasthenic syndromes (CMS) challenge those who suffer from it by causing fatigable muscle weakness, in the most benign cases, to a progressive wasting of muscles that may sentence patients to a wheelchair or even death. Compared to other more common neurological diseases, CMS are rare. Nevertheless, extensive research in CMS is performed in laboratories such as ours. Among the diverse neuromuscular disorders of CMS, we are focusing in the slow-channel congenital myasthenic syndrome (SCS), which is caused by mutations in genes encoding acetylcholine receptor subunits. The study of SCS has evolved from clinical electrophysiological studies to in vitro expression systems and transgenic mice models. The present review evaluates the methodological approaches that are most commonly employed to assess synaptic impairment in SCS and also provides perspectives for new approaches. Electrophysiological methodologies typically employed by physicians to diagnose patients include electromyography, whereas patient muscle samples are used for intracellular recordings, single-channel recordings and toxin binding experiments. In vitro expression systems allow the study of a particular mutation without the need of patient intervention. Indeed, in vitro expression systems have usually been implicated in the development of therapeutic strategies such as quinidine- and fluoxetine-based treatments and, more recently, RNA interference. A breakthrough in the study of SCS has been the development of transgenic mice bearing the mutations that cause SCS. These transgenic mice models have actually been key in the elucidation of the pathogenesis of the SCS mutations by linking IP-3 receptors to calcium overloading, as well as caspases and calpains to the hallmark of SCS, namely endplate myopathy. Finally, we summarize our experiences with suspected SCS patients from a local perspective and comment on one aspect of the contribution of our group in the study of SCS.