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1.
Int J Angiol ; 29(4): 223-228, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33268972

RESUMEN

Coronary computed tomography angiography (CCTA) offers high-resolution anatomic characterization of the coronary vasculature but may be suboptimal for lesions dependent on real-time visualization of flow including chronic total occlusion (CTO). In CTOs, heavy calcification and distal vessel opacification from collateralization may confound luminal assessment. Several studies have examined the role of CCTA in characterizing known CTOs to guide percutaneous coronary intervention (PCI). However, the efficacy of CCTA in the de novo diagnosis of CTOs prior to coronary angiography (CAG) has not been demonstrated. A total of 233 consecutive patients who presented for CAG within a 3-month period of having CCTA were retrospectively reviewed. Those patients with prior diagnosis of CTO or prior bypass of the occluded vessels were excluded. Sensitivity and specificity analysis of CCTA in identifying CTOs using CAG as the gold standard was performed. The prevalence of CTO was 21.11% in the population that met criteria for analysis ( n = 199). The sensitivity of CCTA in predicting CTO was 57.1%, while the specificity was 96.8%. The positive predictive value and negative predictive value of CCTA in detection of CTO were 82.8 and 89.4%, respectively. Our study shows that CCTA has excellent specificity but poor sensitivity in the detection of CTO thus limiting its clinical use in de novo diagnosis. Further studies to determine the effect of de novo CTO diagnosis on clinically important procedural factors, such as radiation exposure, contrast use, and need for repeat procedures, are warranted and may implicate a role for CCTA in this setting.

2.
Cancer Chemother Pharmacol ; 79(4): 673-680, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28280971

RESUMEN

PURPOSE: LY3022859 is an anti-TGFßRII IgG1 monoclonal antibody that inhibits receptor-mediated signaling activation. The primary objective of this phase I study was to determine a phase II dose in patients with advanced solid tumors. Secondary objectives were to assess safety and pharmacokinetics (PK). METHODS: LY3022859 was infused intravenously (IV) at 1.25 mg/kg over 1 h every 2 weeks (Q2W) (cohort 1A) and at flat doses of 12.5 mg (cohort 1B) and 25 mg (cohort 2) over 3 h Q2W. RESULTS: Fourteen patients were enrolled in cohorts 1A (n = 2), 1B (n = 5), and 2 (n = 7). DLTs were experienced by both patients in cohort 1A (infusion-related reaction) and 2 patients in cohort 2 (cytokine release syndrome and infusion-related reaction). No MTD was determined. At the 25 mg dose level (cohort 2), after fifth infusion, LY3022859 had a short t1/2 (4.37-7.80 h) and rapid clearance (CLss, 0.412 L/h). Exposure increased twofold (from 28.5 to 60.2 µg·h/mL) with increase in dose from 12.5 to 25 mg. No accumulation was observed after repeat administration. CONCLUSIONS: The MTD for LY3022859 was not determined. Dose escalation beyond 25 mg was considered unsafe due to worsening symptoms (uncontrolled cytokine release) despite prophylaxis (corticosteroids and antihistamines). TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01646203.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Receptores de Factores de Crecimiento Transformadores beta/antagonistas & inhibidores , Adulto , Anciano , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/farmacocinética , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Estudios de Cohortes , Citocinas/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Semivida , Humanos , Infusiones Intravenosas , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
3.
Ann Oncol ; 27(12): 2216-2224, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27733377

RESUMEN

BACKGROUND: Icrucumab and ramucirumab are recombinant human IgG1 monoclonal antibodies that bind VEGF receptors 1 and 2 (VEGFR-1 and -2), respectively. This randomized phase II study evaluated the antitumor activity and safety of icrucumab and ramucirumab each in combination with mFOLFOX-6 in patients with metastatic colorectal cancer after disease progression on first-line therapy with a fluoropyrimidine and irinotecan. PATIENTS AND METHODS: Eligible patients were randomly assigned to receive mFOLFOX-6 alone (mFOLFOX-6) or in combination with ramucirumab 8 mg/kg IV (RAM+mFOLFOX-6) or icrucumab 15 mg/kg IV (ICR+mFOLFOX-6) every 2 weeks. Randomization was stratified by prior bevacizumab therapy. The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS), tumor response, safety, and PK. RESULTS: In total, 158 patients were randomized, but only 153 received treatment (49 on mFOLFOX-6, 52 on RAM+mFOLFOX-6, and 52 on ICR+mFOLFOX-6). Median PFS was 18.4 weeks on mFOLFOX-6, 21.4 weeks on RAM+mFOLFOX-6, and 15.9 weeks on ICR+mFOLFOX-6 (RAM+mFOLFOX-6 versus mFOLFOX-6, stratified hazard ratio [HR] 1.116 [95% CI 0.713-1.745], P = 0.623; ICR+mFOLFOX-6 versus mFOLFOX-6, stratified HR 1.603 [95% CI 1.011-2.543], P = 0.044). Median survival was 53.6 weeks on mFOLFOX-6, 41.7 weeks on RAM+mFOLFOX-6, and 42.0 weeks on ICR+mFOLFOX-6. The most frequent adverse events reported on the ramucirumab arm (RAM+mFOLFOX-6) were fatigue, nausea, and peripheral sensory neuropathy; those on the icrucumab arm (ICR+mFOLFOX-6) were fatigue, diarrhea, and peripheral sensory neuropathy. Grade ≥3 serious adverse events occurred at comparable frequency across arms. CONCLUSIONS: In this study population, combining ramucirumab or icrucumab with mFOLFOX-6 did not achieve the predetermined improvement in PFS. CLINICALTRIALSGOV: NCT01111604.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias Colorrectales/tratamiento farmacológico , Adulto , Anciano , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Camptotecina/administración & dosificación , Camptotecina/efectos adversos , Camptotecina/análogos & derivados , Neoplasias Colorrectales/patología , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/clasificación , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Humanos , Irinotecán , Leucovorina/administración & dosificación , Leucovorina/efectos adversos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Compuestos Organoplatinos/administración & dosificación , Compuestos Organoplatinos/efectos adversos , Ramucirumab
4.
Leukemia ; 30(4): 889-96, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26442612

RESUMEN

CC-486, the oral formulation of azacitidine (AZA), is an epigenetic modifier and DNA methyltransferase inhibitor in clinical development for treatment of hematologic malignancies. CC-486 administered for 7 days per 28-day treatment cycle was evaluated in a phase 1 dose-finding study. AZA has a short plasma half-life and DNA incorporation is S-phase-restricted; extending CC-486 exposure may increase the number of AZA-affected diseased target cells and maximize therapeutic effects. Patients with lower-risk myelodysplastic syndromes (MDS) received 300 mg CC-486 once daily for 14 days (n=28) or 21 days (n=27) of repeated 28-day cycles. Median patient age was 72 years (range 31-87) and 75% of patients had International Prognostic Scoring System Intermediate-1 risk MDS. Median number of CC-486 treatment cycles was 7 (range 2-24) for the 14-day dosing schedule and 6 (1-24) for the 21-day schedule. Overall response (complete or partial remission, red blood cell (RBC) or platelet transfusion independence (TI), or hematologic improvement) (International Working Group 2006) was attained by 36% of patients receiving 14-day dosing and 41% receiving 21-day dosing. RBC TI rates were similar with both dosing schedules (31% and 38%, respectively). CC-486 was generally well-tolerated. Extended dosing schedules of oral CC-486 may provide effective long-term treatment for patients with lower-risk MDS.


Asunto(s)
Antimetabolitos Antineoplásicos/uso terapéutico , Azacitidina/uso terapéutico , Síndromes Mielodisplásicos/tratamiento farmacológico , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Antimetabolitos Antineoplásicos/farmacocinética , Azacitidina/farmacocinética , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/patología , Estadificación de Neoplasias , Pronóstico , Factores de Riesgo , Seguridad , Distribución Tisular
5.
Leukemia ; 30(3): 536-44, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26500138

RESUMEN

Thrombocytopenia is commonly seen in myelodysplastic syndrome (MDS) patients, and bleeding complications are a major cause of morbidity and mortality. Thrombocytopenia is an independent factor for decreased survival and has been incorporated in newer prognostic scoring systems. The mechanisms of thrombocytopenia are multifactorial and involve a differentiation block of megakaryocytic progenitor cells, leading to dysplastic, hypolobated and microscopic appearing megakaryocytes or increased apoptosis of megakaryocytes and their precursors. Dysregulated thrombopoietin (TPO) signaling and increased platelet destruction through immune or nonimmune mechanisms are frequently observed in MDS. The clinical management of patients with low platelet counts remains challenging and approved chemotherapeutic agents such as lenalidomide and azacytidine can also lead to a transient worsening of thrombocytopenia. Platelet transfusion is the only supportive treatment option currently available for clinically significant thrombocytopenia. The TPO receptor agonists romiplostim and eltrombopag have shown clinical activity in clinical trials in MDS. In addition to thrombopoietic effects, eltrombopag can inhibit leukemic cell proliferation via TPO receptor-independent effects. Other approaches such as treatment with cytokines, immunomodulating drugs and signal transduction inhibitors have shown limited activity in selected groups of MDS patients. Combination trials of approved agents with TPO agonists are ongoing and hold promise for this important clinical problem.


Asunto(s)
Antineoplásicos/uso terapéutico , Regulación Neoplásica de la Expresión Génica , Hemorragia/terapia , Síndromes Mielodisplásicos/terapia , Transfusión de Plaquetas , Trombocitopenia/terapia , Benzoatos/uso terapéutico , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Plaquetas/patología , Diferenciación Celular , Hemorragia/complicaciones , Hemorragia/diagnóstico , Hemorragia/epidemiología , Humanos , Hidrazinas/uso terapéutico , Megacariocitos/efectos de los fármacos , Megacariocitos/metabolismo , Megacariocitos/patología , Síndromes Mielodisplásicos/complicaciones , Síndromes Mielodisplásicos/diagnóstico , Síndromes Mielodisplásicos/epidemiología , Pronóstico , Pirazoles/uso terapéutico , Receptores Fc/uso terapéutico , Receptores de Trombopoyetina/antagonistas & inhibidores , Receptores de Trombopoyetina/genética , Receptores de Trombopoyetina/metabolismo , Proteínas Recombinantes de Fusión/uso terapéutico , Transducción de Señal , Trombocitopenia/complicaciones , Trombocitopenia/diagnóstico , Trombocitopenia/epidemiología , Trombopoyetina/genética , Trombopoyetina/metabolismo , Trombopoyetina/uso terapéutico
6.
Ann R Coll Surg Engl ; 94(2): e99-100, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22391375

RESUMEN

We report the case of an inverted cyclops lesion limiting extension of the knee joint after a four-strand hamstring anterior cruciate ligament (ACL) reconstruction. One case has been reported previously following a bone-tendon-bone reconstruction of the ACL but a similar case has not been reported.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior/efectos adversos , Artropatías/etiología , Accidentes por Caídas , Ligamento Cruzado Anterior/cirugía , Artroscopía/métodos , Femenino , Humanos , Artropatías/fisiopatología , Traumatismos de la Rodilla/etiología , Traumatismos de la Rodilla/fisiopatología , Traumatismos de la Rodilla/cirugía , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/fisiopatología , Rango del Movimiento Articular/fisiología , Rotura/etiología , Rotura/cirugía
7.
J Hand Surg Eur Vol ; 37(8): 728-32, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22357334

RESUMEN

Thirty-eight fingers in 27 patients with Dupuytren's contracture of the proximal interphalangeal joint (PIPJ) in excess of 70° were treated using a staged technique. The first stage involved applying a mini external fixator across the PIPJ for continuous extension over 6 weeks with intensive hand therapy to maintain mobility of the joint and help correct the deformity. Twice weekly during hand therapy sessions the tension of the elastic band across the mini ex-fix was increased, allowing that full active flexion of the PIPJ against the elastic band could still be achieved. The second stage, 4 weeks after the external fixator was applied, involved an open palm technique of fasciectomy for the contracted cords restricting metacarpophalangeal joint movement and dermofasciectomy with full-thickness skin grafting over the proximal phalanx for bands restricting PIPJ movement. The external fixator was used to maintain active extension force until the graft healed. It was generally removed in the outpatient clinic under ring block 2 weeks after the second stage procedure. The patients were followed for a mean of 20.6 (6-48) months. The mean preoperative PIPJ deformity improved from 75° to 37° postoperatively. Overall, 69% of results were rated as good to excellent. Only one patient reported any on-going functional problems. There were eight cases of pin site infections and one case each of loose pins, osteoarthritics at the PIPJ, reflex sympathetic dystrophy, and disease recurrence needing PIPJ fusion. We conclude that our simple staged procedure is a valid alternative in the management of severe Dupuytren's PIPJ contracture.


Asunto(s)
Contractura de Dupuytren/cirugía , Articulaciones de los Dedos/cirugía , Adulto , Anciano , Terapia Combinada , Contractura de Dupuytren/fisiopatología , Fijadores Externos , Fasciotomía , Femenino , Articulaciones de los Dedos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Modalidades de Fisioterapia , Complicaciones Posoperatorias , Recuperación de la Función , Recurrencia , Trasplante de Piel , Resultado del Tratamiento
8.
Leuk Lymphoma ; 49(10): 1963-75, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18949619

RESUMEN

Myelodysplastic syndromes (MDS) are common causes of ineffective hematopoiesis and cytopenias in the elderly. Various myelosuppressive and proinflammatory cytokines have been implicated in the high rates of apoptosis and hematopoietic suppression seen in MDS. We have previously shown that p38 MAPK is overactivated in MDS hematopoietic progenitors, which led to current clinical studies of the selective p38alpha inhibitor, SCIO-469, in this disease. We now demonstrate that the myelosuppressive cytokines TNFalpha and IL-1beta are secreted by bone marrow (BM) cells in a p38 MAPK-dependent manner. Their secretion is stimulated by paracrine interactions between BM stromal and mononuclear cells and cytokine induction correlates with CD34+ stem cell apoptosis in an inflammation-simulated in vitro bone marrow microenvironment. Treatment with SCIO-469 inhibits TNF secretion in primary MDS bone marrow cells and protects cytogenetically normal progenitors from apoptosis ex vivo. Furthermore, p38 inhibition diminishes the expression of TNFalpha or IL-1beta-induced proinflammatory chemokines in BM stromal cells. These data indicate that p38 inhibition has anti-inflammatory effects on the bone marrow microenvironment that complements its cytoprotective effect on progenitor survival. These findings support clinical investigation of p38alpha as a potential therapeutic target in MDS and other related diseases characterised by inflammatory bone marrow failure.


Asunto(s)
Médula Ósea/patología , Mediadores de Inflamación/antagonistas & inhibidores , Síndromes Mielodisplásicos/patología , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Anciano , Citocinas/antagonistas & inhibidores , Citocinas/biosíntesis , Humanos , Indoles/farmacología , Inflamación/etiología , Interleucina-1beta/metabolismo , Síndromes Mielodisplásicos/tratamiento farmacológico , Comunicación Paracrina/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Factor de Necrosis Tumoral alfa/metabolismo
9.
Heredity (Edinb) ; 99(4): 443-51, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17611493

RESUMEN

Understanding the origin and maintenance of eusociality in termites has proved problematic, in part, due to a lack of knowledge concerning the variability and evolutionary changes in termite breeding structure. One way to address this is to compare the population genetics of a broad range of termite species. However, few studies have investigated the population genetics of basal termite taxa. We used 12 polymorphic microsatellite loci to characterize and compare the colony genetic structure of 18 colonies of two basal termite subspecies, Zootermopsis nevadensis nevadensis and Zootermopsis nevadensis nuttingi. The average relatedness (r) among individuals within a colony was high (0.59) and similar to values reported for other termite species. Average relatedness between colony founders was lower (0.21) suggesting the alates outbreed. Genotypes of workers and soldiers in 4 out of the 18 colonies were consistent with reproduction by a single pair of primary reproductives and the remaining colonies were inferred to have been derived from more than two reproductives. Eleven colonies with three or more reproductives were consistent with replacement reproductives (neotenics) and the remaining three colonies included genetic contribution from three or more primary reproductives. Comparisons between the subspecies revealed significant differences in breeding structure, specifically in the number and types of reproductives (that is, primaries or neotenics). Furthermore, we observed a larger proportion of colonies with greater than three primary reproductives compared to more derived termite lineages. Thus, our results suggest that breeding structure can vary significantly among termite taxa.


Asunto(s)
Isópteros/genética , Animales , California , ADN/genética , Evolución Molecular , Variación Genética , Genética de Población , Genotipo , Geografía , Haplotipos , Desequilibrio de Ligamiento , Repeticiones de Microsatélite/genética , Mitocondrias/genética , Modelos Genéticos , Polimorfismo Genético
12.
Injury ; 37 Suppl 3: S18-24, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16963358

RESUMEN

The effect of head injury on systemic physiology, including bone healing is still a topic of vivid discussion. Whether the observed changes genuinely represent accelerated fracture healing or are a form of local heterotopic ossification remains unclear. We aimed to investigate whether in patients with long bone fractures the presence of head injury is associated with accelerated bone healing and excessive callus formation. In total 67 patients were studied 17 with head injury and 50 without head injury (25 treated with reamed and the other 25 with the unreamed nailing technique). Both groups were comparable in terms of age, sex, ISS. All underwent stabilisation of their femoral fracture with intramedullary nailing. The quantification of fracture healing response was estimated by taking the radiological ratio of the largest diameter of callus formed into two planes and the adjacent normal diameter of femoral canal. The minimum follow up of the patients was 12 months. In patients with head injury, the mean time to fracture union was significantly shorter than either the reamed or unreamed group (10.5 weeks compared with 20.5 and 26.9 weeks, p<0.001). The difference between the mean callus to diaphyseal ratio was statistically significant for both the AP and Lateral projections (AP: mean difference 0.462, 95% CI 0.312 to 0.602, p<0.0001, LAT: mean difference 0.289, 95% CI 0.142 to 0.436, p<0.001) with the head injured patients having more florid callus compared to the control group.


Asunto(s)
Callo Óseo/fisiología , Fracturas del Fémur/fisiopatología , Curación de Fractura/fisiología , Adolescente , Adulto , Estudios de Casos y Controles , Femenino , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/cirugía , Fijación de Fractura , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía por Rayos X
13.
J Bone Joint Surg Br ; 88(2): 213-9, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16434527

RESUMEN

We describe the results of surgical treatment in a prospective study of 183 consecutive cases of subluxation (101) and dislocation (82) of the shoulder secondary to obstetric brachial plexus palsy between 1995 and 2000. Neurological recovery was rated 'good' or 'useful' in all children, whose lesions fell into groups 1, 2 or 3 of the Narakas classification. The mean age at operation was 47 months (3 to 204). The mean follow-up was 40 months (24 to 124). The mean gain in function was 3.6 levels (9.4 to 13) using the Mallet score and 2 (2.1 to 4.1) on the Gilbert score. The mean active global range of shoulder movement was increased by 73 degrees ; the mean range of active lateral rotation by 58 degrees and that of supination of the forearm by 51 degrees . Active medial rotation was decreased by a mean of 10 degrees . There were 20 failures. The functional outcome is related to the severity of the neurological lesion, the duration of the dislocation and onset of deformity.


Asunto(s)
Neuropatías del Plexo Braquial/complicaciones , Luxación del Hombro/cirugía , Remodelación Ósea/fisiología , Neuropatías del Plexo Braquial/patología , Neuropatías del Plexo Braquial/fisiopatología , Femenino , Necrosis de la Cabeza Femoral/diagnóstico por imagen , Necrosis de la Cabeza Femoral/etiología , Humanos , Húmero/diagnóstico por imagen , Húmero/fisiopatología , Lactante , Recién Nacido , Ligamentos Articulares/diagnóstico por imagen , Ligamentos Articulares/patología , Ligamentos Articulares/fisiopatología , Masculino , Complicaciones Posoperatorias , Estudios Prospectivos , Radiografía , Rango del Movimiento Articular/fisiología , Reoperación , Luxación del Hombro/etiología , Luxación del Hombro/patología , Articulación del Hombro/diagnóstico por imagen , Articulación del Hombro/patología , Articulación del Hombro/fisiopatología , Insuficiencia del Tratamiento , Resultado del Tratamiento
14.
J Hered ; 96(5): 572-5, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15994421

RESUMEN

Members of the genus Cryptocercus are xylophagous, wingless, subsocial cockroaches that inhabit decaying logs in temperate forests. Given their winglessness, subsocial living, and the patchy distribution of food resources (decomposing logs), it is likely that Cryptocercus populations are substructured. Allozyme variation at eight polymorphic loci was assayed for 10 subpopulations of Cryptocercus darwini and 13 subpopulations of Cryptocercus wrighti, both of which are distributed in the Appalachian Mountains. The mean F(IS) was 0.13 and F(ST) was about 0.25 for both C. darwini and C. wrighti. The relatedness among individuals of a subpopulation of both species was not significantly different from that expected among full sibs. In terms of how genetic variation is partitioned, C. darwini and C. wrighti differed from each other substantially. Most of the genetic variation occurred among subpopulations of C. wrighti in the same region and among subpopulations of C. darwini in different regions. We discuss the factors that may have contributed to the observed similarities and differences in the breeding structure of the two species.


Asunto(s)
Cucarachas/genética , Variación Genética , Genética de Población , Animales , Región de los Apalaches , Cucarachas/enzimología , Frecuencia de los Genes , Isoenzimas , Especificidad de la Especie
15.
Skeletal Radiol ; 34(6): 351-4, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15761744

RESUMEN

Chondromas are tumours that develop in relation to the periosteum and, although they are common around the knee, most reports deal with soft tissue chondromas in para-articular locations or intracortical tumours in extra-articular regions. We report a rare case of an intra-articular chondroma in a 16-year-old boy of Asian origin developing in the region of the medial femoral condyle of the femur and extending into the femoral sulcus and the patellofemoral joint.


Asunto(s)
Neoplasias Óseas/diagnóstico , Condroma/diagnóstico , Artropatías/diagnóstico , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/patología , Adolescente , Artroscopía/métodos , Biopsia/métodos , Neoplasias Óseas/cirugía , Condroma/cirugía , Diagnóstico Diferencial , Estudios de Seguimiento , Humanos , Artropatías/cirugía , Articulación de la Rodilla/cirugía , Imagen por Resonancia Magnética/métodos , Masculino , Dolor/etiología , Radiografía , Enfermedades Raras
16.
Insect Biochem Mol Biol ; 32(7): 765-75, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12044493

RESUMEN

An acetylcholinesterase (AChE, EC 3.1.1.7) cDNA was cloned and characterized from a greenbug (Schizaphis graminum (Rondani)) cDNA library. The complete cDNA (3283 bp) contains a 2028-bp open reading frame encoding 676 amino acid residues. The putative AChE preproenzyme has a 17 amino acid signal peptide, a 78 amino acid activation peptide and a mature enzyme of 581 amino acid residues. The first nine amino acid residues (YTSDDPLII) that were determined by sequencing the N-terminus of a 72-kDa AChE purified from the greenbug matched the nine residues deduced from the cDNA. The key amino acid residues, including the three residues Ser206 (200 in Torpedo), Glu332 (327) and His446 (440) forming a catalytic triad, three pairs of cysteine putatively forming intrachain disulfide bonds, and 10 out of the 14 aromatic residues lining the active site gorge of the Torpedo AChE, are conserved. However, Ser336 (Phe331) in the greenbug substituted an aromatic amino acid residue that is conserved in all other known AChEs. Northern blot analysis of mRNA revealed a 3.7-kb transcript, and Southern blot analysis suggested a single copy of this gene in the greenbug. The deduced amino acid sequence is most similar to AChE1 of the nematodes Caenorhabditis briggsae and C. elegans with 43% identity. Phylogenetic analysis showed that the greenbug AChE formed a cluster with those of nematodes, a squid and ticks, and grouped out of the insect cluster. This result suggests that the cloned gene evolved from a different duplicate gene lineage of insect AChEs.


Asunto(s)
Acetilcolinesterasa/genética , Áfidos/enzimología , Evolución Molecular , Acetilcolinesterasa/clasificación , Secuencia de Aminoácidos , Animales , Áfidos/genética , Secuencia de Bases , Clonación Molecular , ADN Complementario , Datos de Secuencia Molecular , Filogenia , Homología de Secuencia de Aminoácido
17.
Mol Phylogenet Evol ; 21(1): 162-5, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11603946

RESUMEN

The wood-feeding cockroaches of the genus Cryptocercus occur in temperate forests. Of the seven known species, five occur in the United States and two in Eurasia. Until 1997, all populations in the United States were considered a single species. Populations in the western United States were elevated to a species status based on variation in DNA sequence and morphology. In 1999, three new species were described from the eastern United States based on variation in chromosome number and mitochondrial DNA, bringing the number of species in the United States to five. The objective of this study was to determine if the DNA sequence of nuclear rRNA also signals the existence of four species in the eastern United States and to compare the inferred relationships with those proposed based on mitochondrial sequences. We obtained the DNA sequence from a portion of the 5.8S and 28S rRNA genes and the entire ITS2 region from 38 individuals and 30 additional clones to assess intraindividual, intraspecific, and interspecific variation. We found extensive sequence variation among the various species and little or no intraindividual and intraspecific variation. Phylogenetic analysis indicated the existence of monophyletic lineages among the eastern United States samples, which largely corresponded to the four species previously described. The inferred relationships were well-supported by bootstrap analysis and decay indices. Although the nuclear rRNA sequences resulted in a coherent phylogenetic tree, the ITS2 region contained many insertions and deletions, which may introduce homoplasy and ambiguity in alignment as more taxa are added to the data set.


Asunto(s)
Cucarachas/genética , ADN Ribosómico/genética , Filogenia , Animales , Núcleo Celular/genética , Cucarachas/clasificación , ADN Ribosómico/química , ADN Espaciador Ribosómico/genética , Variación Genética , Datos de Secuencia Molecular , ARN Ribosómico 28S/genética , ARN Ribosómico 5.8S/genética , Análisis de Secuencia de ADN , Especificidad de la Especie
18.
Proc Biol Sci ; 268(1465): 393-8, 2001 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-11270436

RESUMEN

Cryptocercus are subsocial, xylophagous cockroaches that live in temperate forests. Like other cockroaches, Cryptocercus harbour endosymbiotic bacteria in their fat bodies. Two species of Cryptocercus occur in the palaearctic, one each in eastern Russia and south-central China. In the USA, there are five species: one in the north-west and four in the south-east. Little is known about the relationship between the Eurasian and North American Cryptocercus or the causes of the disjunct distribution. Here, a molecular phylogeny for six out of the seven Cryptocercus species and their endosymbionts is inferred in an attempt to understand the evolution and biogeography of the genus. Our analysis showed that the North American Cryptocercus are monophyletic, suggesting that a single colonization event was followed by vicariance. There was complete concordance between the host and endosymbiont phylogenetic trees. Divergence estimates based on endosymbiont DNA sequences suggested that the palaearctic and nearctic Cryptocercus diverged 70-115 million years (Myr) ago and the eastern- and western-USA species diverged 53-88 Myr ago. These divergence estimates were correlated with biogeographical events, and a hypothesis is presented to explain the current distribution of Cryptocercus. Our findings suggest that Cryptocercus has had a long evolutionary history, dating back to the Jurassic.


Asunto(s)
Bacterias/genética , Evolución Biológica , Cucarachas/microbiología , Simbiosis , Animales , Bacterias/clasificación , Cucarachas/clasificación , ADN Bacteriano/análisis , ADN Ribosómico/análisis , Variación Genética , Filogenia , ARN Ribosómico 16S , ARN Ribosómico 23S , Análisis de Secuencia de ADN
19.
J Chromatogr Sci ; 39(2): 70-2, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11245229

RESUMEN

A new assay method has been developed for the quantitation of promethazine (PMZ) with a sensitivity and reproducibility as good as any previously reported method. This method is also capable of quantitatively determining three metabolites of PMZ (monodemethylated, sulphoxidated, and monodemethylated sulphoxidated PMZ), which has not been previously described. The method uses high-performance liquid chromatography with amperometric and UV detection simultaneously and requires only one extraction step from serum with chloroform. The method uses trifluoperazine as the internal standard. The limit of detection level for PMZ is 1.0 ng/ml when a 0.2-mL specimen of plasma is assayed. A validation study is also conducted for evaluating the recovery, precision, linearity of response, sensitivity, and selectivity of the method.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Antagonistas de los Receptores Histamínicos H1/sangre , Promazina/análogos & derivados , Prometazina/sangre , Humanos , Promazina/sangre , Prometazina/análogos & derivados , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
Mol Phylogenet Evol ; 11(2): 236-45, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10191068

RESUMEN

Wasps of the braconid subfamily Aphidiinae are solitary endoparasitoids of aphids. Several aspects of their biology have been the focus of intuitive evolutionary hypotheses which could be tested with a robust phylogeny. Phylogenetic hypotheses have been proposed previously for aphidiines based on morphology, embryology, and DNA sequences. However, many of them are based on a limited number of characters and/or taxa and lack congruence. In addition, many of the inferred phylogenies have not been based upon cladistic analysis. Therefore, a phylogenetic study of Aphidiinae was undertaken, utilizing 465 bp of DNA sequence of the mitochondrial NADH1 dehydrogenase gene. DNA sequences were obtained from 40 taxa, including 14 genera and three outgroups. It is suggested that in agreement with most of the previously proposed phylogenies, the aphidiines, each of the three recognized tribes (Praini, Ephedrini, Aphidiini), and most genera are monophyletic. In contrast to previously proposed phylogenies, the clade of Praon + Dyscritulus (=Praini), rather than Ephedrini, is basal among the aphidiines.


Asunto(s)
ADN Mitocondrial/genética , Himenópteros/genética , NADH Deshidrogenasa/genética , Filogenia , Animales , Áfidos/parasitología , Larva , Modelos Biológicos , Datos de Secuencia Molecular , ARN Ribosómico 28S
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