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1.
Clin Pediatr (Phila) ; : 99228241241894, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38554017

RESUMEN

Pediatric bone injuries are traditionally diagnosed using radiography. However, ultrasonography is emerging as an alternative due to its speed and minimal invasiveness. This study assessed the diagnostic capabilities of ultrasound before radiography in a group of 186 children with suspected long bone fractures at Saint Etienne University Hospital (Saint-Priest-en-Jarez, France). Patients with open trauma and severe deformity were excluded. Ultrasonography demonstrated 88.2% sensitivity and 86.4% specificity, with better results for forearm injuries. Of the 186 cases, 162 were consistent with radiography and 24 varied. Factors influencing an accurate diagnosis included the presence of indirect signs, operator experience, and examination duration, while indirect signs often led to misinterpretation. Although ultrasound cannot completely replace radiography due to its limitations in identifying deeper fractures, this study revealed its substantial efficacy and ease, supporting its potential utility in pediatric trauma emergencies.

2.
ISME Commun ; 4(1): ycae005, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38439943

RESUMEN

Insects typically acquire their beneficial microbes early in development. Endosymbionts housed intracellularly are commonly integrated during oogenesis or embryogenesis, whereas extracellular microbes are only known to be acquired after hatching by immature instars such as larvae or nymphs. Here, however, we report on an extracellular symbiont that colonizes its host during embryo development. Tortoise beetles (Chrysomelidae: Cassidinae) host their digestive bacterial symbiont Stammera extracellularly within foregut symbiotic organs and in ovary-associated glands to ensure its vertical transmission. We outline the initial stages of symbiont colonization and observe that although the foregut symbiotic organs develop 3 days prior to larval emergence, they remain empty until the final 24 h of embryo development. Infection by Stammera occurs during that timeframe and prior to hatching. By experimentally manipulating symbiont availability to embryos in the egg, we describe a 12-h developmental window governing colonization by Stammera. Symbiotic organs form normally in aposymbiotic larvae, demonstrating that these Stammera-bearing structures develop autonomously. In adults, the foregut symbiotic organs are already colonized following metamorphosis and host a stable Stammera population to facilitate folivory. The ovary-associated glands, however, initially lack Stammera. Symbiont abundance subsequently increases within these transmission organs, thereby ensuring sufficient titers at the onset of oviposition ~29 days following metamorphosis. Collectively, our findings reveal that Stammera colonization precedes larval emergence, where its proliferation is eventually decoupled in adult beetles to match the nutritional and reproductive requirements of its host.

3.
Curr Biol ; 34(8): 1621-1634.e9, 2024 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-38377997

RESUMEN

Timing the acquisition of a beneficial microbe relative to the evolutionary history of its host can shed light on the adaptive impact of a partnership. Here, we investigated the onset and molecular evolution of an obligate symbiosis between Cassidinae leaf beetles and Candidatus Stammera capleta, a γ-proteobacterium. Residing extracellularly within foregut symbiotic organs, Stammera upgrades the digestive physiology of its host by supplementing plant cell wall-degrading enzymes. We observe that Stammera is a shared symbiont across tortoise and hispine beetles that collectively comprise the Cassidinae subfamily, despite differences in their folivorous habits. In contrast to its transcriptional profile during vertical transmission, Stammera elevates the expression of genes encoding digestive enzymes while in the foregut symbiotic organs, matching the nutritional requirements of its host. Despite the widespread distribution of Stammera across Cassidinae beetles, symbiont acquisition during the Paleocene (∼62 mya) did not coincide with the origin of the subfamily. Early diverging lineages lack the symbiont and the specialized organs that house it. Reconstructing the ancestral state of host-beneficial factors revealed that Stammera encoded three digestive enzymes at the onset of symbiosis, including polygalacturonase-a pectinase that is universally shared. Although non-symbiotic cassidines encode polygalacturonase endogenously, their repertoire of plant cell wall-degrading enzymes is more limited compared with symbiotic beetles supplemented with digestive enzymes from Stammera. Highlighting the potential impact of a symbiotic condition and an upgraded metabolic potential, Stammera-harboring beetles exploit a greater variety of plants and are more speciose compared with non-symbiotic members of the Cassidinae.


Asunto(s)
Escarabajos , Simbiosis , Animales , Escarabajos/fisiología , Escarabajos/microbiología , Escarabajos/genética , Gammaproteobacteria/genética , Gammaproteobacteria/fisiología , Evolución Biológica , Evolución Molecular
4.
Orthop Traumatol Surg Res ; 110(1S): 103762, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37992867

RESUMEN

Cervical spine injuries in children are a common reason for emergency room visits, while bone, ligament or spinal cord cervical lesions are relatively rare (1-1.5% of severe trauma in children) and mainly involve the upper cervical spine. The main causes are sports injuries, accidents at home and traffic accidents. Clinical triage is needed to avoid unnecessary radiation exposure from imaging. We propose a protocol to optimize the diagnosis and treatment. In children, conservative treatment using rigid immobilization (cervical collar or halo-vest) is the preferred option in stable and/or minimally displaced injuries. Frequent clinical and radiological monitoring is required to ensure the patient's condition does not deteriorate due to inappropriate or poorly tolerated treatment. In these cases, surgical treatment can be proposed as second-line treatment. Internal fixation is indicated as the first-line treatment if the injury is unstable or a neurological deficit is present. The fixation methods must be adapted to the pediatric population by taking into account the vertebral volume and residual growth potential. Intraoperative CT scans or neuronavigation can make the surgical procedure safer and easier. Clinical, radiographic and CT scan monitoring should continue until the end of growth in a child who underwent surgical treatment to quickly detect any mechanical complications or sagittal imbalance due to poor craniocervical or cervicothoracic alignment. LEVEL OF EVIDENCE: IV.


Asunto(s)
Fracturas de la Columna Vertebral , Traumatismos Vertebrales , Humanos , Niño , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/cirugía , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Vértebras Cervicales/lesiones , Radiografía , Tomografía Computarizada por Rayos X , Fijación Interna de Fracturas/métodos , Traumatismos Vertebrales/diagnóstico por imagen , Traumatismos Vertebrales/cirugía
5.
Nat Microbiol ; 8(12): 2234-2237, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38030904

Asunto(s)
Microbiología
7.
PLoS Pathog ; 19(7): e1011497, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37498848

RESUMEN

As vectors of numerous plant pathogens, herbivorous insects play a key role in the epidemiology of plant disease. But how phytopathogens impact the metabolism, physiology, and fitness of their insect vectors is often unexplored within these tripartite interactions. Here, we examine the diverse symbioses forged between insects and members of the ascomycete fungal genus Fusarium. While Fusarium features numerous plant pathogens that are causal to diseases such as wilts and rots, many of these microbes also engage in stable mutualisms across several insect clades. Matching a diversity in symbiont localization and transmission routes, we highlight the various roles fusaria fulfill towards their insect hosts, from upgrading their nutritional physiology to providing defense against natural enemies. But as the insect partner is consistently herbivorous, we emphasize the convergent benefit Fusarium derives in exchange: propagation to a novel host plant. Collectively, we point to the synergy arising between a phytopathogen and its insect vector, and the consequences inflicted on their shared plant.


Asunto(s)
Ascomicetos , Fusarium , Animales , Fusarium/genética , Simbiosis , Insectos/microbiología , Plantas/microbiología
8.
J Med Life ; 16(2): 277-283, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36937468

RESUMEN

Burnout syndrome, characterized by chronic unmanageable workplace stress, has been linked to lower gastrointestinal disorders, including irritable bowel syndrome. However, the relationship between burnout syndrome and irritable bowel syndrome among medical health providers and medical students in Saudi Arabia has not been fully explored. This cross-sectional correlational study was conducted in Southern Saudi Arabia from 2021 to 2022 and involved 931 medical health providers and medical students who completed an electronic questionnaire. The study assessed the presence and severity of burnout and irritable bowel syndrome and examined their relationship. Burnout syndrome was evaluated using the Maslach Burnout Inventory-Student Survey (MBI-SS), while irritable bowel syndrome criteria and severity were assessed using validated tools. The study found that 85% of medical health providers and medical students experienced high levels of burnout and irritable bowel syndrome severity, with physicians and nurses mainly affected. Occupational exhaustion was high in 44.4% of participants, while depersonalization was high in 53% of participants. Personal accomplishment was low in 73.5% of participants. Mild, moderate, and severe irritable bowel syndrome was reported in 25.6%, 23.8%, and 12% of participants, respectively. The study highlights a significant association between burnout syndrome and irritable bowel syndrome severity among medical health providers and medical students in Saudi Arabia. These findings underscore the importance of developing effective interventions to prevent and manage burnout syndrome and related health issues among healthcare professionals and medical students in the region.


Asunto(s)
Agotamiento Profesional , Personal de Salud , Síndrome del Colon Irritable , Estudiantes de Medicina , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Agotamiento Profesional/epidemiología , Estudios Transversales , Personal de Salud/psicología , Personal de Salud/estadística & datos numéricos , Síndrome del Colon Irritable/epidemiología , Arabia Saudita/epidemiología , Estudiantes de Medicina/psicología , Estudiantes de Medicina/estadística & datos numéricos , Encuestas y Cuestionarios , Índice de Severidad de la Enfermedad
9.
Elife ; 122023 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-36734377

RESUMEN

Honeybees rely on their microbial gut symbionts to overcome a potent toxin found in pollen and nectar.


Asunto(s)
Néctar de las Plantas , Simbiosis , Abejas , Animales , Polen
10.
Annu Rev Entomol ; 68: 451-469, 2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36266253

RESUMEN

Insect eggs are exposed to a plethora of abiotic and biotic threats. Their survival depends on both an innate developmental program and genetically determined protective traits provided by the parents. In addition, there is increasing evidence that (a) parents adjust the egg phenotype to the actual needs, (b) eggs themselves respond to environmental challenges, and (c) egg-associated microbes actively shape the egg phenotype. This review focuses on the phenotypic plasticity of insect eggs and their capability to adjust themselves to their environment. We outline the ways in which the interaction between egg and environment is two-way, with the environment shaping the egg phenotype but also with insect eggs affecting their environment. Specifically, insect eggs affect plant defenses, host biology (in the case of parasitoid eggs), and insect oviposition behavior. We aim to emphasize that the insect egg, although it is a sessile life stage, actively responds to and interacts with its environment.


Asunto(s)
Adaptación Fisiológica , Insectos , Femenino , Animales , Oviposición/fisiología , Plantas , Fenotipo , Óvulo
11.
Curr Biol ; 32(19): 4114-4127.e6, 2022 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-35987210

RESUMEN

Many insects rely on microbial protection in the early stages of their development. However, in contrast to symbiont-mediated defense of eggs and young instars, the role of microbes in safeguarding pupae remains relatively unexplored, despite the susceptibility of the immobile stage to antagonistic challenges. Here, we outline the importance of symbiosis in ensuring pupal protection by describing a mutualistic partnership between the ascomycete Fusarium oxysporum and Chelymorpha alternans, a leaf beetle. The symbiont rapidly proliferates at the onset of pupation, extensively and conspicuously coating C. alternans during metamorphosis. The fungus confers defense against predation as symbiont elimination results in reduced pupal survivorship. In exchange, eclosing beetles vector F. oxysporum to their host plants, resulting in a systemic infection. By causing wilt disease, the fungus retained its phytopathogenic capacity in light of its symbiosis with C. alternans. Despite possessing a relatively reduced genome, F. oxysporum encodes metabolic pathways that reflect its dual lifestyle as a plant pathogen and a defensive insect symbiont. These include virulence factors underlying plant colonization, along with mycotoxins that may contribute to the defensive biochemistry of the insect host. Collectively, our findings shed light on a mutualism predicated on pupal protection of an herbivorous beetle in exchange for symbiont dissemination and propagation.


Asunto(s)
Ascomicetos , Escarabajos , Micotoxinas , Animales , Insectos , Plantas , Pupa , Factores de Virulencia
12.
Proc Biol Sci ; 289(1973): 20220386, 2022 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-35473381

RESUMEN

Faithful transmission of beneficial symbionts is critical for the persistence of mutualisms. Many insect groups rely on extracellular routes that require microbial symbionts to survive outside the host during transfer. However, given a prolonged aposymbiotic phase in offspring, how do mothers mitigate the risk of symbiont loss due to unsuccessful transmission? Here, we investigated symbiont regulation and reacquisition during extracellular transfer in the tortoise beetle, Chelymorpha alternans (Coleoptera: Cassidinae). Like many cassidines, C. alternans relies on egg caplets to vertically propagate its obligate symbiont Candidatus Stammera capleta. On average, each caplet is supplied with 12 symbiont-bearing spheres where Stammera is embedded. We observe limited deviation (±2.3) in the number of spheres allocated to each caplet, indicating strict maternal control over symbiont supply. Larvae acquire Stammera 1 day prior to eclosion but are unable to do so after hatching, suggesting that a specific developmental window governs symbiont uptake. Experimentally manipulating the number of spheres available to each egg revealed that a single sphere is sufficient to ensure successful colonization by Stammera relative to the 12 typically packaged within a caplet. Collectively, our findings shed light on a tightly regulated symbiont transmission cycle optimized to ensure extracellular transfer.


Asunto(s)
Escarabajos , Simbiosis , Animales , Enterobacteriaceae , Insectos , Larva , Simbiosis/fisiología
13.
Annu Rev Entomol ; 67: 201-219, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34606364

RESUMEN

Beetles are hosts to a remarkable diversity of bacterial symbionts. In this article, we review the role of these partnerships in promoting beetle fitness following a surge of recent studies characterizing symbiont localization and function across the Coleoptera. Symbiont contributions range from the supplementation of essential nutrients and digestive or detoxifying enzymes to the production of bioactive compounds providing defense against natural enemies. Insights on this functional diversity highlight how symbiosis can expand the host's ecological niche, but also constrain its evolutionary potential by promoting specialization. As bacterial localization can differ within and between beetle clades, we discuss how it corresponds to the microbe's beneficial role and outline the molecular and behavioral mechanisms underlying symbiont translocation and transmission by its holometabolous host. In reviewing this literature, we emphasize how the study of symbiosis can inform our understanding of the phenotypic innovations behind the evolutionary success of beetles.


Asunto(s)
Bacterias , Escarabajos , Simbiosis , Animales , Evolución Biológica , Escarabajos/microbiología , Ecosistema
14.
Orthop Traumatol Surg Res ; 108(1): 102992, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34186217

RESUMEN

INTRODUCTION: Fifth metacarpal neck fracture is the most frequent type of hand fracture in adolescents between 13 and 16 years of age. It mainly affects males and the dominant hand. The L-pinning technique combines intramedullary anterograde pinning and transverse pinning between the 4th and 5th metacarpals. The present study aimed to assess L-pinning without postoperative immobilization in displaced 5th metacarpal fracture in adolescents with low residual growth. MATERIALS AND METHODS: Data for patients aged between 13 and 16 years, operated on for closed 5th metacarpal neck fracture between January 2017 and June 2019, were analyzed retrospectively. Surgery was indicated for angulation with>30° palmar tilt and/or horizontal malalignment. The technique consisted in intramedullary anterograde pinning and transverse pinning between the 4th and 5th metacarpal heads. No postoperative immobilization was applied. Hardware was removed as of day 28. The final clinical check-up was at≥12 months. RESULTS: Eighteen patients, all male, with a mean age of 14 years, were included. All had bone age≥14 years. Mean palmar tilt was 52°±6.8° versus 6°±2.4° postoperatively, for a mean correction of 45°±4.3°. Mean operating time was 15min, and X-ray exposure 0.36minutes for a mean radiation dose of 2.89 cGy/cm2. At hardware removal, all patients showed radiologic consolidation. At 3 months, 5th ray ranges of motion were normal, with no local complications. Functional results were maintained at last follow-up (≥12 months). CONCLUSION: L-pinning seemed reliable in terms of feasibility and stability of reduction in 5th metacarpal neck fracture in adolescents. Absence of postoperative immobilization facilitated self-rehabilitation and accelerated functional recovery. LEVEL OF EVIDENCE: IV.


Asunto(s)
Fijación Intramedular de Fracturas , Fracturas Óseas , Traumatismos de la Mano , Huesos del Metacarpo , Fracturas de la Columna Vertebral , Adolescente , Fijación Intramedular de Fracturas/métodos , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/cirugía , Traumatismos de la Mano/cirugía , Humanos , Masculino , Huesos del Metacarpo/diagnóstico por imagen , Huesos del Metacarpo/lesiones , Huesos del Metacarpo/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
15.
Appl Environ Microbiol ; 87(12): e0021221, 2021 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-33863703

RESUMEN

A pervasive pest of stored leguminous products, the bean beetle Callosobruchus maculatus (Coleoptera: Chrysomelidae) associates with a simple bacterial community during adulthood. Despite its economic importance, little is known about the compositional stability, heritability, localization, and metabolic potential of the bacterial symbionts of C. maculatus. In this study, we applied community profiling using 16S rRNA gene sequencing to reveal a highly conserved bacterial assembly shared between larvae and adults. Dominated by Firmicutes and Proteobacteria, this community is localized extracellularly along the epithelial lining of the bean beetle's digestive tract. Our analysis revealed that only one species, Staphylococcus gallinarum (phylum Firmicutes), is shared across all developmental stages. Isolation and whole-genome sequencing of S. gallinarum from the beetle gut yielded a circular chromosome (2.8 Mb) and one plasmid (45 kb). The strain encodes complete biosynthetic pathways for the production of B vitamins and amino acids, including tyrosine, which is increasingly recognized as an important symbiont-supplemented precursor for cuticle biosynthesis in beetles. A carbohydrate-active enzyme search revealed that the genome codes for a number of digestive enzymes, reflecting the nutritional ecology of C. maculatus. The ontogenic conservation of the gut microbiota in the bean beetle, featuring a "core" community composed of S. gallinarum, may be indicative of an adaptive role for the host. In clarifying symbiont localization and metabolic potential, we further our understanding and study of a costly pest of stored products. IMPORTANCE From supplementing essential nutrients to detoxifying plant secondary metabolites and insecticides, bacterial symbionts are a key source of adaptations for herbivorous insect pests. Despite the pervasiveness and geographical range of the bean beetle Callosobruchus maculatus, the role of microbial symbioses in its natural history remains understudied. Here, we demonstrate that the bean beetle harbors a simple gut bacterial community that is stable throughout development. This community localizes along the insect's digestive tract and is largely dominated by Staphylococcus gallinarum. In elucidating symbiont metabolic potential, we highlight its possible adaptive significance for a widespread agricultural pest.


Asunto(s)
Escarabajos/microbiología , Microbioma Gastrointestinal/genética , Genoma Bacteriano , Staphylococcus/genética , Simbiosis , Animales , Femenino , Genómica , Larva/microbiología , Masculino , Óvulo/microbiología , Staphylococcus/aislamiento & purificación
16.
Curr Biol ; 30(15): 2875-2886.e4, 2020 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-32502409

RESUMEN

Numerous adaptations are gained in light of a symbiotic lifestyle. Here, we investigated the obligate partnership between tortoise leaf beetles (Chrysomelidae: Cassidinae) and their pectinolytic Stammera symbionts to detail how changes to the bacterium's streamlined metabolic range can shape the digestive physiology and ecological opportunity of its herbivorous host. Comparative genomics of 13 Stammera strains revealed high functional conservation, highlighted by the universal presence of polygalacturonase, a primary pectinase targeting nature's most abundant pectic class, homogalacturonan (HG). Despite this conservation, we unexpectedly discovered a disparate distribution for rhamnogalacturonan lyase, a secondary pectinase hydrolyzing the pectic heteropolymer, rhamnogalacturonan I (RG-I). Consistent with the annotation of rhamnogalacturonan lyase in Stammera, cassidines are able to depolymerize RG-I relative to beetles whose symbionts lack the gene. Given the omnipresence of HG and RG-I in foliage, Stammera that encode pectinases targeting both substrates allow their hosts to overcome a greater diversity of plant cell wall polysaccharides and maximize access to the nutritionally rich cytosol. Possibly facilitated by their symbionts' expanded digestive range, cassidines additionally endowed with rhamnogalacturonan lyase appear to utilize a broader diversity of angiosperms than those beetles whose symbionts solely supplement polygalacturonase. Our findings highlight how symbiont metabolic diversity, in concert with host adaptations, may serve as a potential source of evolutionary innovations for herbivorous lineages.


Asunto(s)
Escarabajos/fisiología , Fenómenos Fisiológicos del Sistema Digestivo , Sistema Digestivo/microbiología , Enterobacteriaceae/fisiología , Herbivoria/fisiología , Interacciones Huésped-Parásitos/fisiología , Fenómenos Fisiológicos de las Plantas , Simbiosis/fisiología , Animales , Enterobacteriaceae/enzimología , Poligalacturonasa , Polisacárido Liasas
17.
ISME J ; 14(3): 866-870, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31796934

RESUMEN

While genome erosion is extensively studied in intracellular symbionts, the metabolic implications of reductive evolution in microbes subsisting extracellularly remain poorly understood. Stammera capleta-an extracellular symbiont in leaf beetles-possesses an extremely reduced genome (0.27 Mb), enabling the study of drastic reductive evolution in the absence of intracellularity. Here, we outline the genomic and transcriptomic profiles of Stammera and its host to elucidate host-symbiont metabolic interactions. Given the symbiont's substantial demands for nutrients and membrane components, the host's symbiotic organ shows repurposing of internal resources by upregulating nutrient transporters and cuticle-processing genes targeting epithelial chitin. Facilitated by this supplementation and its localization, Stammera exhibits a highly streamlined gene expression profile and a fermentation pathway for energy conversion, sharply contrasting the respiratory metabolism retained by most intracellular symbionts. Our results provide insights into a tightly regulated and metabolically integrated extracellular symbiosis, expanding our understanding of the minimal metabolism required to sustain life outside of a host cell.


Asunto(s)
Escarabajos/microbiología , Enterobacteriaceae/fisiología , Animales , Escarabajos/fisiología , Enterobacteriaceae/genética , Enterobacteriaceae/aislamiento & purificación , Fermentación , Genómica , Simbiosis
18.
Mol Ecol ; 28(23): 5172-5187, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31638716

RESUMEN

The adaptation of herbivorous insects to new host plants is key to their evolutionary success in diverse environments. Many insects are associated with mutualistic gut bacteria that contribute to the host's nutrition and can thereby facilitate dietary switching in polyphagous insects. However, how gut microbial communities differ between populations of the same species that feed on different host plants remains poorly understood. Most species of Pyrrhocoridae (Hemiptera: Heteroptera) are specialist seed-feeders on plants in the family Malvaceae, although populations of one species, Probergrothius angolensis, have switched to the very distantly related Welwitschia mirabilis plant in the Namib Desert. We first compared the development and survival of laboratory populations of Pr. angolensis with two other pyrrhocorids on seeds of Welwitschia and found only Pr. angolensis was capable of successfully completing its development. We then collected Pr. angolensis in Namibia from Malvaceae and Welwitschia host plants, respectively, to assess their bacterial and fungal community profiles using high-throughput amplicon sequencing. Comparison with long-term laboratory-reared insects indicated stable associations of Pr. angolensis with core bacteria (Commensalibacter, Enterococcus, Bartonella and Klebsiella), but not with fungi or yeasts. Phylogenetic analyses of core bacteria revealed relationships to other insect-associated bacteria, but also found new taxa indicating potential host-specialized nutritional roles. Importantly, the microbial community profiles of bugs feeding on Welwitschia versus Malvaceae revealed stark and consistent differences in the relative abundance of core bacterial taxa that correlate with the host-plant switch; we were able to reproduce this result through feeding experiments. Thus, a dynamic gut microbiota may provide a means for insect adaptation to new host plants in new environments when food plants are extremely divergent.


Asunto(s)
Bacterias/genética , Evolución Biológica , Heterópteros/genética , Microbiota/genética , Animales , Bacterias/clasificación , Cycadopsida/genética , Cycadopsida/microbiología , Microbioma Gastrointestinal , Herbivoria , Heterópteros/microbiología , Magnoliopsida/genética , Magnoliopsida/microbiología , Simbiosis/genética
19.
Cell ; 171(7): 1520-1531.e13, 2017 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-29153832

RESUMEN

Pectin, an integral component of the plant cell wall, is a recalcitrant substrate against enzymatic challenges by most animals. In characterizing the source of a leaf beetle's (Cassida rubiginosa) pectin-degrading phenotype, we demonstrate its dependency on an extracellular bacterium housed in specialized organs connected to the foregut. Despite possessing the smallest genome (0.27 Mb) of any organism not subsisting within a host cell, the symbiont nonetheless retained a functional pectinolytic metabolism targeting the polysaccharide's two most abundant classes: homogalacturonan and rhamnogalacturonan I. Comparative transcriptomics revealed pectinase expression to be enriched in the symbiotic organs, consistent with enzymatic buildup in these structures following immunostaining with pectinase-targeting antibodies. Symbiont elimination results in a drastically reduced host survivorship and a diminished capacity to degrade pectin. Collectively, our findings highlight symbiosis as a strategy for an herbivore to metabolize one of nature's most complex polysaccharides and a universal component of plant tissues.


Asunto(s)
Escarabajos/microbiología , Enterobacteriaceae/genética , Genoma Bacteriano , Animales , Escarabajos/fisiología , Enterobacteriaceae/clasificación , Enterobacteriaceae/enzimología , Enterobacteriaceae/fisiología , Tamaño del Genoma , Pectinas/metabolismo , Simbiosis
20.
Clin Rehabil ; 31(12): 1583-1591, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28459163

RESUMEN

OBJECTIVE: To investigate the effectiveness of mirror therapy combined with neuromuscular electrical stimulation in promoting motor recovery of the lower limbs and walking ability in patients suffering from foot drop after stroke. DESIGN: Randomized controlled study. SETTING: Inpatient rehabilitation center of a teaching hospital. SUBJECTS: Sixty-nine patients with foot drop. INTERVENTION: Patients were randomly divided into three groups: control, mirror therapy, and mirror therapy + neuromuscular electrical stimulation. All groups received interventions for 0.5 hours/day and five days/week for four weeks. MAIN MEASURES: 10-Meter walk test, Brunnstrom stage of motor recovery of the lower limbs, Modified Ashworth Scale score of plantar flexor spasticity, and passive ankle joint dorsiflexion range of motion were assessed before and after the four-week period. RESULTS: After four weeks of intervention, Brunnstrom stage ( P = 0.04), 10-meter walk test ( P < 0.05), and passive range of motion ( P < 0.05) showed obvious improvements between patients in the mirror therapy and control groups. Patients in the mirror therapy + neuromuscular electrical stimulation group showed better results than those in the mirror therapy group in the 10-meter walk test ( P < 0.05). There was no significant difference in spasticity between patients in the two intervention groups. However, compared with patients in the control group, patients in the mirror therapy + neuromuscular electrical stimulation group showed a significant decrease in spasticity ( P < 0.001). CONCLUSION: Therapy combining mirror therapy and neuromuscular electrical stimulation may help improve walking ability and reduce spasticity in stroke patients with foot drop.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Trastornos Neurológicos de la Marcha/rehabilitación , Rehabilitación de Accidente Cerebrovascular/métodos , Accidente Cerebrovascular/terapia , Femenino , Trastornos Neurológicos de la Marcha/fisiopatología , Humanos , Pierna/fisiopatología , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/fisiopatología , Resultado del Tratamiento , Caminata
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