Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Más filtros

Banco de datos
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Mol Biol Evol ; 39(3)2022 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-35192709

RESUMEN

Insects have evolved numerous adaptations and colonized diverse terrestrial environments. Several polyneopterans, including dictyopterans (cockroaches and mantids) and locusts, have developed oothecae, but little is known about the molecular mechanism, physiological function, and evolutionary significance of ootheca formation. Here, we demonstrate that the cockroach asymmetric colleterial glands produce vitellogenins, proline-rich protein, and glycine-rich protein as major ootheca structural proteins (OSPs) that undergo sclerotization and melanization for ootheca formation through the cooperative protocatechuic acid pathway and dopachrome and dopaminechrome subpathway. Functionally, OSP sclerotization and melanization prevent eggs from losing water at warm and dry conditions, and thus effectively maintain embryo viability. Dictyopterans and locusts convergently evolved vitellogenins, apolipoprotein D, and laminins as OSPs, whereas within Dictyoptera, cockroaches and mantids independently developed glycine-rich protein and fibroins as OSPs. Highlighting the ecological-evolutionary importance, convergent ootheca formation represents a successful reproductive strategy in Polyneoptera that promoted the radiation and establishment of cockroaches, mantids, and locusts.


Asunto(s)
Cucarachas , Escarabajos , Aclimatación , Animales , Insectos , Reproducción
2.
BMC Biol ; 20(1): 278, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36514097

RESUMEN

BACKGROUND: In insects, an interplay between the activities of distinct hormones, such as juvenile hormone (JH) and 20-hydroxyecdysone (20E), regulates the progression through numerous life history hallmarks. As a crucial endocrine factor, JH is mainly synthesized in the corpora allata (CA) to regulate multiple physiological and developmental processes, including molting, metamorphosis, and reproduction. During the last century, significant progress has been achieved in elucidating the JH signal transduction pathway, while less progress has been made in dissecting the regulatory mechanism of JH biosynthesis. Previous work has shown that receptor tyrosine kinase (RTK) signaling regulates hormone biosynthesis in both insects and mammals. Here, we performed a systematic RNA interference (RNAi) screening to identify RTKs involved in regulating JH biosynthesis in the CA of adult Blattella germanica females. RESULTS: We found that the epidermal growth factor receptor (Egfr) is required for promoting JH biosynthesis in the CA of adult females. The Egf ligands Vein and Spitz activate Egfr, followed by Ras/Raf/ERK signaling, and finally activation of the downstream transcription factor Pointed (Pnt). Importantly, Pnt induces the transcriptional expression of two key enzyme-encoding genes in the JH biosynthesis pathway: juvenile hormone acid methyltransferase (JHAMT) and methyl farnesoate epoxidase (CYP15A1). Dual-luciferase reporter assay shows that Pnt is able to activate a promoter region of Jhamt. In addition, electrophoretic mobility shift assay confirms that Pnt directly binds to the - 941~ - 886 nt region of the Jhamt promoter. CONCLUSIONS: This study reveals the detailed molecular mechanism of Egfr signaling in promoting JH biosynthesis in the German cockroach, shedding light on the intricate regulation of JH biosynthesis during insect development.


Asunto(s)
Blattellidae , Animales , Femenino , Blattellidae/genética , Corpora Allata/metabolismo , Hormonas Juveniles/metabolismo , Metamorfosis Biológica , Transducción de Señal/fisiología , Mamíferos
3.
Int Orthop ; 40(12): 2533-2545, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27198870

RESUMEN

OBJECTIVE: The object of the present meta-analysis is to compare the effectiveness of transforaminal epidural steroid injection (TFESI) and interlaminar epidural steroid injection (ILESI) for treating patients with low back pain (LBP) secondary to lumbosacral radicular pain. METHODS: A systematic search was performed in the PubMed and Embase databases and the Cochrane Library for relevant literature published through January 2016. The randomized controlled trials (RCTs) and controlled observational studies were selected, which did not only compare TFESI with ILESI but also reported the available data. The Cochrane Collaboration's Handbook and Newcastle-Ottawa Scale (NOS) were used for the methodological quality assessments of the RCTs and observational studies respectively. The meta-analysis was performed using the Revman 5.2 software. RESULTS: A total of 931 patients from nine RCTs and four observational studies were subjected to meta-analysis. In primary outcomes, the TFESI patients experienced superior pain relief compared with the TFESI patients in RCTs (P = 0.01), but not in observational studies (p = 0.63). The pooled data of RCTs showed that the TFESI group presented superior clinical results in terms of visual analogue scale (VAS) than the ILESI group (p = 0.0005). Moreover, the numeric rating scale (NRS) specifically favored TFESI in the RCTs (p < 0000.1). Similar functional improvement and oswentry disability index (ODI) score were observed between TFESI and ILESI in RCTs (P = 0.62). In secondary outcomes, meta-analysis of RCTs and observational studies revealed that there were no statistically significant differences between both groups in regard to procedure frequency, surgery rate, and ventral epidural spread. CONCLUSIONS: According to the results of meta-analysis, TFESI to manage LBP provides superior short term pain relief and equal functional improvement when compared to ILESI. It has not shown a statistically significant difference between both groups with regard to procedure frequency, surgery rate, and ventral epidural spread.


Asunto(s)
Glucocorticoides/administración & dosificación , Inyecciones Epidurales/métodos , Dolor de la Región Lumbar/tratamiento farmacológico , Humanos , Región Lumbosacra , Manejo del Dolor , Dimensión del Dolor , Resultado del Tratamiento
4.
Medicine (Baltimore) ; 101(4): e28773, 2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35089256

RESUMEN

RATIONALE: Pipkin III femoral head fracture dislocation (FHFD) is rarely observed in clinical practice, and its outcome is alarming. A considerable proportion of Pipkin III fractures result from repeated or forceful closed reduction of an irreducible FHFD. Pipkin type III fractures pose a therapeutic challenge. Most patients underwent total hip arthroplasty. PATIENT CONCERNS: A 34-year-old man experienced high-energy trauma to the left hip from a terrible traffic accident. Radiography and computed tomography (CT) at the local hospital revealed a left posterior FHFD. Emergency close reduction of the hip was performed.48 hours later, the patient was transferred to our institution. New radiography and CT examinations demonstrated an iatrogenic femoral neck fracture (FNF) associated with FHFD. In addition, a right talar fracture was observed. DIAGNOSIS: Pipkin III fracture combined with contralateral talar fracture. INTERVENTIONS: Considering his Pipkin fracture classification (Pipkin Type-III) and the time to surgery after his injury (>48 hours), the patient underwent left total hip arthroplasty uneventfully, followed by below-ankle plaster cast immobilization for his right ankle. OUTCOMES: At the 6-month follow-up, the patient was able to walk pain-free, and plain radiographs were satisfactory, with no evidence of heterotopic ossification or osteonecrosis of the talus. LESSONS: Before emergency closed reduction, early recognition of the unique characteristics of an irreducible FHFD is essential to avoid iatrogenic femoral neck fracture.


Asunto(s)
Reducción Cerrada/efectos adversos , Fracturas del Cuello Femoral/cirugía , Cabeza Femoral/cirugía , Fractura-Luxación/prevención & control , Fijación Interna de Fracturas/métodos , Luxación de la Cadera/cirugía , Fracturas de Cadera/diagnóstico por imagen , Enfermedad Iatrogénica , Accidentes de Tránsito , Adulto , Fracturas del Cuello Femoral/clasificación , Fracturas del Cuello Femoral/etiología , Cabeza Femoral/diagnóstico por imagen , Cabeza Femoral/lesiones , Fractura-Luxación/diagnóstico por imagen , Fractura-Luxación/etiología , Fractura-Luxación/cirugía , Luxación de la Cadera/diagnóstico por imagen , Luxación de la Cadera/etiología , Fracturas de Cadera/etiología , Fracturas de Cadera/cirugía , Humanos , Enfermedad Iatrogénica/prevención & control , Masculino , Reducción Abierta , Resultado del Tratamiento
5.
Zhongguo Gu Shang ; 30(3): 261-263, 2017 Mar 25.
Artículo en Zh | MEDLINE | ID: mdl-29349967

RESUMEN

OBJECTIVE: To explore curative effects of external fixation combined with single hip plaster in treating children with femoral subtrochanteric fracture. METHODS: Form March 2009 to July 2016, 15 children with femoral subtrochanteric fracture were treated with external fixation combined with single hip plaster, including 9 males and 6 females with a mean age of 8.5 years old ranging from 5 to 14 years old. According to fracture classification of Seinsheimer, 3 cases were type IIA, 4 cases were type IIB, 3 cases were type IIC, 2 cases were type IIIA, 1 case was type IIIB, 1 case was type IV, 1 case was type V. Complications and radiographs were retrospectively reviewed. Postoperative function of hips were evaluated according to Sanders criteria. RESULTS: All children were followed up from 16 to 48 months with an average of 32 months. No early closure of epiphysis, bone nonunion and breakage of screw occurred. According to the Sanders score standard of hip function, the result was excellent in 14 cases, good in 1 case. There were no hip inversion, limb shortening, excessive growth and other malformations. CONCLUSIONS: External fixation combined with single hip plaster for the treatment of children is a safe and effective fixation, which provide a new choice of femoral subtrochanteric fracture.


Asunto(s)
Moldes Quirúrgicos , Fracturas del Fémur/cirugía , Fijación de Fractura/métodos , Adolescente , Tornillos Óseos , Niño , Preescolar , Femenino , Fracturas del Fémur/clasificación , Cadera , Humanos , Masculino , Resultado del Tratamiento
6.
Spine (Phila Pa 1976) ; 41(11): E661-E666, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26656057

RESUMEN

STUDY DESIGN: A prospective study. OBJECTIVE: To investigate the association between microstructural nerve roots changes on diffusion tensor imaging (DTI) and clinical symptoms and their duration in patients with lumbar disc herniation. SUMMARY OF BACKGROUND DATA: The ability to identify microstructural properties of the nervous system with DTI has been demonstrated in many studies. However, there are no data regarding the association between microstructural changes evaluated using DTI and symptoms assessed with the Oswestry Disability Index (ODI) and their duration. METHODS: Forty consecutive patients with foraminal disc herniation affecting unilateral sacral 1 (S1) nerve roots were enrolled in this study. DTI with tractography was performed on the S1 nerve roots. Clinical symptoms were evaluated using an ODI questionnaire for each patient, and the duration of clinical symptoms was noted based on the earliest instance of leg pain and numbness. Mean fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were calculated from tractography images. RESULTS: The mean FA value of the compressed lumbar nerve roots was significantly lower than the FA of the contralateral nerve roots (P < 0.001). No notable difference in ADC was observed between compressed nerve roots and contralateral nerve roots (P = 0.517). In the compressed nerve roots, a significant negative association was observed between FA values and ODI and symptom duration. However, an obvious positive association was observed between ODI and ADC values and duration on the compressed side. CONCLUSION: Significant changes in diffusion parameters were found in the compressed sacral nerves in patients with lumbar disc herniation and leg pain, indicating that the microstructure of the nerve root has been damaged. LEVEL OF EVIDENCE: 3.


Asunto(s)
Imagen de Difusión Tensora/tendencias , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Síndromes de Compresión Nerviosa/diagnóstico por imagen , Raíces Nerviosas Espinales/diagnóstico por imagen , Adulto , Estudios de Cohortes , Femenino , Humanos , Desplazamiento del Disco Intervertebral/epidemiología , Masculino , Persona de Mediana Edad , Síndromes de Compresión Nerviosa/epidemiología , Adulto Joven
7.
Artículo en Zh | MEDLINE | ID: mdl-16827391

RESUMEN

OBJECTIVE: To investigate clinical significance and surgical protocols about the balance of the lower limb lengths in the total hip arthroplasty. METHODS: Forty-eight patients undergoing the unilateral primary total hip arthroplasty from March 2000 to October 2004 were retrospectively studied. In 12 hips, the prostheses were of the cement type; in 36 hips, of the mixture type. Thirty patients with an equal limb length had a fractured femoral neck, 10 patients had a shortened (1.0-2.0 cm) limb, 6 patients had a shortened (2.0-4.0 cm) limb, and 2 patients had a shortened (4.0-6.0 cm) limb. Based on the clinical measurement and radiographic examination, the surgical protocols were designed, the hip prosthesis type was chosen, and the neck length of the femoral prosthesis and the position of osteotomy were estimated. By the wearing of the acetabula properly, the best rotation point was found out during the operation. The cut plane of the femoral neck was adjusted according to the results of the radiographic and other examinations. The neck length was readjusted after the insertion of the prosthesis so as to achieve an intended limb-length equalization. RESULTS: All the patients were followed up for 3-42 months. According to the Harris scoring system, clinical results were excellent in 30 patients, good in 12, fair in 4, and poor in 2. Of the 30 patients with an equal limb before operation, 5 were lengthened 1.0-2.0 cm in their lower limbs, and 1 lengthened 2. 5 cm postoperatively. Of the 18 patients with shortened limbs before operation, 10 returned to the same lengths in their lower limbs, 6 were lengthened 1.0-2.0 cm in their lower limbs, but 2 with seriously-shortened lower limbs for congenital dysplasia of the hip joint were still shortened 2.0-3.0 cm in the limb length after operation. The Harris hip scores revealed an average of 92.3 points in the patients with an equal limb length, and 88.6 points in the patients with shortened limbs. CONCLUSION: Many factors, such as surgical protocols, prosthesis type designs, and the management techniques during the operation, can affect the limb length after operation. As the limb length discrepancy will make the patients feel disappointed, the clinical measurements are very important before operation. Application of the comprehensive appraisal methods during the operation, use of the soft tissue balance method, and skills for obtaining an equal limb length during the total hip arthroplasty are also important for improving the surgical result further.


Asunto(s)
Artroplastia de Reemplazo de Cadera/métodos , Extremidad Inferior/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Antropometría , Femenino , Estudios de Seguimiento , Humanos , Periodo Intraoperatorio , Extremidad Inferior/anatomía & histología , Masculino , Persona de Mediana Edad , Radiografía , Estudios Retrospectivos , Resultado del Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA