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1.
Br J Haematol ; 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850184

RESUMEN

In Australia, bortezomib-based induction (V-IND) is used in >90% of newly diagnosed transplant-eligible multiple myeloma (MM) patients. Four cycles of V-IND with bortezomib-cyclophosphamide-dexamethasone or bortezomib-lenalidomide-dexamethasone are available via the Pharmaceutical Benefits Scheme prior to autologous stem cell transplantation (ASCT). Patients who demonstrate suboptimal response or who are refractory to V-IND demonstrate inferior survival, representing a subgroup of MM where an unmet need persists. We evaluated an early, response-adapted approach in these patients by switching to an intensive sequential therapeutic strategy incorporating daratumumab-lenalidomide-dexamethasone-based (DRd) salvage, high-dose melphalan ASCT followed by DRd consolidation and R maintenance. The overall response rate following four cycles of DRd salvage was 72% (95% credible interval: 57.9-82.4); prespecified, dual, Bayesian proof-of-concept criteria were met. Euro-flow minimal residual disease (MRD) negativity was 46% in the intention-to-treat population and 79% in the evaluable population following 12 cycles of DRd consolidation. At the 24-month follow-up, median progression-free survival and overall survival were not reached. DRd salvage was well tolerated with grade 3 and 4 events reported in 24% and 8% respectively. Response-adapted DRd combined with ASCT achieves high rates of MRD negativity and durable disease control in this functional high-risk group.

2.
Br J Haematol ; 202(3): 530-538, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37332079

RESUMEN

We evaluated re-induction incorporating carfilzomib-thalidomide-dexamethasone (KTd) and autologous stem cell transplantation (ASCT) for newly diagnosed multiple myeloma (NDMM) refractory, or demonstrating a suboptimal response, to non-IMID bortezomib-based induction. KTd salvage consisted of thalidomide 100 mg daily and dexamethasone 20 mg orally combined with carfilzomib 56 mg/m2 days 1, 2, 8, 9, 15 and 16, of each 28-day cycle. Following four cycles, patients achieving a stringent complete response proceeded to ASCT whereas those who did not received a further two cycles then ASCT. Consolidation consisted of two cycles of KTd then Td to a total of 12 months post-ASCT therapy. Primary end-point was the overall response rate (ORR) with KTd prior to ASCT. Fifty patients were recruited. The ORR was 78% with EuroFlow MRD negativity of 34% in the intention-to-treat population and 65% in the evaluable population at 12 months post-ASCT. With follow-up >38 months median PFS and OS have not been reached with PFS and OS at 36 months of 64% and 80%, respectively. KTd was well tolerated with grade 3 and grade ≥4 adverse events rates of 32% and 10%, respectively. Response adaptive utilisation of KTd with ASCT is associated with both high-quality responses and durable disease control in functional high-risk NDMM.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia , Linfoma , Mieloma Múltiple , Humanos , Mieloma Múltiple/tratamiento farmacológico , Talidomida , Dexametasona , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante Autólogo , Bortezomib/uso terapéutico , Leucemia/tratamiento farmacológico , Linfoma/tratamiento farmacológico
3.
Ann R Coll Surg Engl ; 104(9): 700-702, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35442836

RESUMEN

INTRODUCTION: Management of the airway in the perioperative period for patients requiring major head and neck ablative surgery has commonly included the performance of elective surgical tracheostomy. This has been standard practice in most maxillofacial units across the UK, including ours. However, the COVID-19 pandemic and emerging guidelines on aerosol-generating procedures required us to revisit the need for a perioperative tracheostomy. METHODS: We present our series of 29 consecutive cases, cared for during the first wave of the COVID-19 pandemic, that were managed either using surgical tracheostomy or overnight tracheal intubation. RESULTS: Out of 29 patients 3 received a surgical tracheostomy. The average duration of tracheostomy use was 8 days. Twenty patients were managed using a period of overnight tracheal intubation. Average duration of tracheal intubation was 1.2 days, with an average intensive care unit stay of 1.7 days. The average duration of hospital stay was 15.8 days for patients managed with overnight tracheal intubation and 30.1 days for patients who received a surgical tracheostomy. The return to theatre rate was 13.8% for reasons including flap failure and neck space infection. There were no airway issues reported in this series of patients. CONCLUSIONS: Our findings suggest that overnight tracheal intubation can be a safe alternative to surgical tracheostomy in the majority of cases.


Asunto(s)
COVID-19 , Traqueostomía , Humanos , Traqueostomía/métodos , COVID-19/epidemiología , Pandemias , Estudios Retrospectivos , Intubación Intratraqueal/métodos
4.
Opt Express ; 27(5): 7602-7615, 2019 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-30876322

RESUMEN

We present a novel deflectometry implementation termed Infinite Deflectometry. The technique provides a full aperture surface reconstruction sag map of freeform surfaces, including previously challenging to measure optics such as highly convex surfaces. The method relies on the creation of a virtual source enclosure around the tested optic, which creates a virtual 2π-steradian measurement range. To demonstrate the performance, a fast f/1.26 convex optical surface was measured with a commercial interferometer and with the Infinite Deflectometry system. After removing Zernike terms 1 through 37, the metrology tests resulted in absolute RMS surface values of 18.48 nm and 16.26 nm, respectively. Additionally, a freeform Alvarez lens was measured with the new technique and measured 22.34 𝜇m of surface sag RMS after piston, tip/tilt, and defocus had been removed. The result deviated by 488 nm RMS from a profilometer measurement while standard interferometry failed to measure the Alvarez lens due to its non-nulled wavefront dynamic range limitation.

5.
Intern Med J ; 45(3): 335-43, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25735577

RESUMEN

Options for treatment of elderly patients with multiple myeloma have expanded substantially following the development of immunomodulatory drugs (IMiD), proteasome inhibitors and with enhancement in safety of high-dose therapy and autologous stem cell transplant (HDT + ASCT). The recognition of biological heterogeneity among elderly patients has made delivery of therapy more challenging. An individualised approach to treatment selection is recommended in an era in which highly efficacious treatment options are available for transplant-ineligible patients. Here, we summarise recommendations for patients who are considered unsuitable for HDT + ASCT, including pretreatment considerations, and induction, maintenance and supportive care therapies.


Asunto(s)
Comités Consultivos/normas , Fundaciones/normas , Mieloma Múltiple/epidemiología , Mieloma Múltiple/terapia , Trasplante de Células Madre , Australia/epidemiología , Humanos , Factores Inmunológicos/uso terapéutico , Mieloma Múltiple/diagnóstico , Inhibidores de Proteasoma/uso terapéutico , Trasplante Autólogo , Resultado del Tratamiento
6.
Intern Med J ; 45(1): 94-105, 2015 01.
Artículo en Inglés | MEDLINE | ID: mdl-25582938

RESUMEN

The survival of patients with multiple myeloma (MM) has improved substantially since the introduction in the late 1980s of high-dose chemotherapy (HDT) supported by autologous stem cell transplantation (ASCT). Further improvements have been observed following the availability of immunomodulatory drugs (IMiD) such as thalidomide and lenalidomide, and the proteasome inhibitor, bortezomib. Here, we summarise the recommendations of the Medical Scientific Advisory Group to the Myeloma Foundation of Australia for patients considered suitable for HDT + ASCT as part of initial therapy. These recommendations incorporate the various phases of treatment: induction, HDT conditioning and maintenance therapy.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/normas , Mieloma Múltiple/tratamiento farmacológico , Guías de Práctica Clínica como Asunto , Sociedades Científicas , Comités Consultivos , Australia/epidemiología , Supervivencia sin Enfermedad , Humanos , Mieloma Múltiple/epidemiología , Tasa de Supervivencia/tendencias , Trasplante Autólogo , Resultado del Tratamiento
7.
Intern Med J ; 45(4): 371-82, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25169210

RESUMEN

Systemic AL amyloidosis is a plasma cell dyscrasia with a characteristic clinical phenotype caused by multi-organ deposition of an amyloidogenic monoclonal protein. This condition poses a unique management challenge due to the complexity of the clinical presentation and the narrow therapeutic window of available therapies. Improved appreciation of the need for risk stratification, standardised use of sensitive laboratory testing for monitoring disease response, vigilant supportive care and the availability of newer agents with more favourable toxicity profiles have contributed to the improvement in treatment-related mortality and overall survival seen over the past decade. Nonetheless, with respect to the optimal management approach, there is a paucity of high-level clinical evidence due to the rarity of the disease, and enrollment in clinical trials is still the preferred approach where available. This review will summarise the Clinical Practice Guidelines on the Management of Systemic Light Chain (AL) Amyloidosis recently prepared by the Medical Scientific Advisory Group of the Myeloma Foundation of Australia. It is hoped that these guidelines will assist clinicians in better understanding and optimising the management of this difficult disease.


Asunto(s)
Comités Consultivos/normas , Amiloidosis/terapia , Manejo de la Enfermedad , Fundaciones/normas , Mieloma Múltiple/terapia , Amiloidosis/diagnóstico , Amiloidosis/epidemiología , Australia/epidemiología , Humanos , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/epidemiología
9.
Clin Exp Immunol ; 175(1): 49-58, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24032527

RESUMEN

The causes of multiple myeloma (MM) remain obscure and there are few known risk factors; however, natural killer T (NKT) cell abnormalities have been reported in patients with MM, and therapeutic targeting of NKT cells is promoted as a potential treatment. We characterized NKT cell defects in treated and untreated patients with MM and determined the impact of lenalidomide therapy on the NKT cell pool. Lenalidomide is an immunomodulatory drug with co-stimulatory effects on NKT cells in vitro and is an approved treatment for MM, although its mode of action in that context is not well defined. We find that patients with relapsed/progressive MM had a marked deficiency in NKT cell numbers. In contrast, newly diagnosed patients had relatively normal NKT cell frequency and function prior to treatment, although a specific NKT cell deficiency emerged after high-dose melphalan and autologous stem cell transplantation (ASCT) regimen. This also impacted NK cells and conventional T cells, but the recovery of NKT cells was considerably delayed, resulting in a prolonged, treatment-induced NKT cell deficit. Longitudinal analysis of individual patients revealed that lenalidomide therapy had no in-vivo impact on NKT cell numbers or cytokine production, either as induction therapy, or as maintenance therapy following ASCT, indicating that its clinical benefits in this setting are independent of NKT cell modulation.


Asunto(s)
Factores Inmunológicos/administración & dosificación , Mieloma Múltiple , Células T Asesinas Naturales , Talidomida/análogos & derivados , Citocinas/sangre , Citocinas/inmunología , Femenino , Humanos , Lenalidomida , Recuento de Linfocitos , Masculino , Mieloma Múltiple/sangre , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/inmunología , Mieloma Múltiple/patología , Células T Asesinas Naturales/inmunología , Células T Asesinas Naturales/metabolismo , Células T Asesinas Naturales/patología , Talidomida/administración & dosificación
10.
Leukemia ; 24(3): 592-600, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20072154

RESUMEN

Myelodysplastic syndrome (MDS) comprises a group of clonal bone marrow disorders characterized by ineffective hematopoiesis and increased predisposition to acute myeloid leukemia. The causes of MDS remain poorly defined, but several studies have reported the NKT cell compartment of patients with MDS is deficient in number and functionally defective. In support of a central role for NKT cells, a pilot clinical study reported that lenalidomide (an approved treatment for MDS) increased NKT cell numbers in patients with MDS, and several in vitro studies showed lenalidomide specifically promoted NKT cell proliferation and cytokine production. We tested this in a much larger study and confirm a moderate in vitro augmentation of some NKT cell functions by lenalidomide, but find no impact on the NKT cell compartment of patients treated with lenalidomide, despite a consistently positive clinical response. We further show that the frequency and cytokine production of NKT cells is normal in patients with MDS before treatment and remains stable throughout 10 months of lenalidomide therapy. Collectively, our data challenge the concept that NKT cell defects contribute to the development of MDS, and show that a clinical response to lenalidomide is not dependent on modulation of NKT cell frequency or function.


Asunto(s)
Antineoplásicos/uso terapéutico , Síndromes Mielodisplásicos/tratamiento farmacológico , Células T Asesinas Naturales/inmunología , Talidomida/análogos & derivados , Anciano , Anciano de 80 o más Años , Complejo CD3/análisis , Citocinas/biosíntesis , Femenino , Humanos , Lenalidomida , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/inmunología , Células T Asesinas Naturales/efectos de los fármacos , Talidomida/farmacología , Talidomida/uso terapéutico
11.
Leukemia ; 24(1): 22-32, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19907437

RESUMEN

Immunomodulatory drugs (IMiDs) are thalidomide analogues, which possess pleiotropic anti-myeloma properties including immune-modulation, anti-angiogenic, anti-inflammatory and anti-proliferative effects. Their development was facilitated by an improved understanding in myeloma (MM) biology and initiated a profound shift in the therapeutic approach towards MM. Despite the diverse effects of IMiDs in vitro, the relative contribution of each effect towards their ultimate anti-MM activity is still unclear. Based on in vitro data, it appears that anti-proliferative effects and downregulation of crucial cytokines are their most important anti-MM attributes. Although the co-stimulatory effects on T and NK cells have been heralded as a unique and important property of IMiDs towards enhancing anti-MM immune activity, these in vitro effects have yet to be firmly corroborated in vivo. Much is yet to be elucidated regarding the complex interplay of immunomodulatory cytokines that occurs in vivo, which ultimately dictates the net effects of IMiDs in MM-the understanding of which is necessary to facilitate optimal manipulation of these drugs in future MM management.


Asunto(s)
Factores Inmunológicos/farmacología , Mieloma Múltiple/tratamiento farmacológico , Talidomida/análogos & derivados , Inhibidores de la Angiogénesis/farmacología , Antiinflamatorios/farmacología , Citotoxicidad Celular Dependiente de Anticuerpos , Antineoplásicos/farmacología , Factores de Transcripción Forkhead/análisis , Humanos , Factores Inmunológicos/uso terapéutico , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/inmunología , Activación de Linfocitos , Mieloma Múltiple/inmunología , Osteoclastos/efectos de los fármacos , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología
12.
Intern Med J ; 39(5): 290-5, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19371392

RESUMEN

BACKGROUND: Bortezomib has been shown to be a safe and efficacious for the treatment of relapsed and refractory multiple myeloma (MM). Here we report a subset analysis of Australian and New Zealand data from the International Extended Access Programme for bortezomib. METHODS: Patients with more than or equal to two prior lines of therapy were given bortezomib 1.3 mg/m(2) (i.v. bolus days 1, 4, 8, 11) for up to eight 21-day cycles (C). Dexamethasone, 20 mg/day p. o. on the day of, and day after, bortezomib was added after C2 for progressive disease or after C4 for stable disease. Efficacy was assessed using modified Southwest Oncology Group criteria in the intent-to-treat group. Results were compared between the Australian and New Zealand and international cohort. RESULTS: One hundred and eleven patients from 16 centres (55% men, median age 61.9 years) had a median of 5.2 +/- 2.8 treatment cycles of bortezomib. Among them, 82% had > or =3 prior therapies. Grade 3-4 treatment-related adverse events were reported in 57 patients (52%); the most common were thrombocytopenia (25.7%), anaemia (8.3%), peripheral neuropathy (7.3%) and diarrhoea (7.3%). Responses were evaluable in 106 patients: 22% achieved a best response of complete response/response and 20% partial response (overall response rate of 42%). Median times to first and best responses were 42 days and 69 days, respectively. Compared with the international cohort, the cohorts from Australian and New Zealand showed inferior overall response rates (54 vs 42%, P = 0.001), possibly due to heavier pretreatment (82% greater than or equal to three prior therapies vs 68%, P < 0.001). CONCLUSION: Our analysis confirms that bortezomib is safe and effective in relapsed and refractory MM in a real-life clinical setting.


Asunto(s)
Ácidos Borónicos/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Pirazinas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Australia/epidemiología , Ácidos Borónicos/efectos adversos , Bortezomib , Estudios de Cohortes , Femenino , Enfermedades Gastrointestinales/inducido químicamente , Enfermedades Gastrointestinales/epidemiología , Humanos , Cooperación Internacional , Masculino , Persona de Mediana Edad , Mieloma Múltiple/epidemiología , Mieloma Múltiple/prevención & control , Nueva Zelanda/epidemiología , Pirazinas/efectos adversos , Recurrencia , Resultado del Tratamiento
14.
Neuroreport ; 15(12): 1987-91, 2004 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-15305151

RESUMEN

Schizophrenia is characterized by thought disorders, hallucinations and delusions. Genetic studies have shown a high linkage at chromosome 6q16-21. Among the genes located in this region is the glutamate receptor ionotropic kainate 2 gene (GRIK2 or GLUR6), a functional candidate for susceptibility to schizophrenia. In this study, transmission of GRIK2 was evaluated in 356 schizophrenic patients from three different clinical centers. Whereas paternal transmission shows equilibrium, we observed maternal transmission disequilibrium of GRIK2 in the largest population (p=0.03), which was still significant when all populations were added (p=0.05). These results are similar to the maternal GRIK2 transmission disequilibrium previously reported for autism, and support the presence of a susceptibility gene for schizophrenia at 6q16.


Asunto(s)
Desequilibrio de Ligamiento , Madres , Receptores de Ácido Kaínico/genética , Esquizofrenia/genética , Alelos , Estudios de Casos y Controles , Cromosomas Humanos Par 6 , Susceptibilidad a Enfermedades , Femenino , Genómica , Genotipo , Humanos , Masculino , Polimorfismo de Nucleótido Simple , Receptor de Ácido Kaínico GluK2
15.
Mol Psychiatry ; 7(3): 302-10, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-11920157

RESUMEN

A genome scan was previously performed and pointed to chromosome 6q21 as a candidate region for autism. This region contains the glutamate receptor 6 (GluR6 or GRIK2) gene, a functional candidate for the syndrome. Glutamate is the principal excitatory neurotransmitter in the brain and is directly involved in cognitive functions such as memory and learning. We used two different approaches, the affected sib-pair (ASP) method and the transmission disequilibrium test (TDT), to investigate the linkage and association between GluR6 and autism. The ASP method, conducted with additional markers on the 51 original families and in eight new sibling pairs, showed a significant excess of allele sharing, generating an elevated multipoint maximum LOD score (ASPEX MLS = 3.28). TDT analysis, performed in the ASP families and in an independent data set of 107 parent-offspring trios, indicated a significant maternal transmission disequilibrium (TDTall P = 0.0004). Furthermore, TDT analysis (with only one affected proband per family) showed significant association between GluR6 and autism (TDT association P = 0.008). In contrast to maternal transmission, paternal transmission of GluR6 alleles was as expected in the absence of linkage, suggesting a maternal effect such as imprinting. Mutation screening was performed in 33 affected individuals, revealing several nucleotide polymorphisms (SNPs), including one amino acid change (M867I) in a highly conserved domain of the intracytoplasmic C-terminal region of the protein. This change is found in 8% of the autistic subjects and in 4% of the control population and seems to be more maternally transmitted than expected to autistic males (P = 0.007). Taken together, these data suggest that GluR6 is in linkage disequilibrium with autism.


Asunto(s)
Trastorno Autístico/genética , Cromosomas Humanos Par 6 , Ligamiento Genético , Receptores de Ácido Kaínico/genética , Secuencia de Aminoácidos , Encéfalo/fisiopatología , Niño , Mapeo Cromosómico , Exones , Familia , Femenino , Marcadores Genéticos , Genotipo , Ácido Glutámico/fisiología , Humanos , Masculino , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Mapeo Restrictivo , Receptor de Ácido Kaínico GluK2
16.
Mol Psychiatry ; 7(2): 217-9, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-11840316

RESUMEN

The male to female ratio in autism is 4:1 in the global autistic population, but increases to 23:1 in autistic subjects without physical or brain abnormalities.(1) Despite this well-recognised gender difference, male predisposition to autistic disorder remains unexplained and the role of sex chromosomes is still debated. Numerical and structural abnormalities of the sex chromosomes are among the most frequently reported chromosomal disorders associated with autism. However, genome scans have failed to detect linkage on the X chromosome(2,3,4) and this approach cannot study the non-recombining region of the Y chromosome. In this study, we searched for a specific Y chromosome effect in autistic subjects. Using informative Y-polymorphic markers, the Y chromosome haplotypes of 111 autistic subjects from France, Sweden and Norway were defined and compared with relevant control populations. No significant difference in Y-haplotype distribution between the affected and control groups was observed. Although this study cannot exclude the presence of a Y susceptibility gene, our results are not suggestive of a Y chromosome effect in autism.


Asunto(s)
Trastorno Autístico/genética , Cromosoma Y , Niño , Femenino , Marcadores Genéticos , Haplotipos , Humanos , Masculino , Factores Sexuales
17.
Genomics ; 78(1-2): 38-45, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11707071

RESUMEN

Capture of cellular mRNA by mobile elements has been an evolutionary catalyst for the spread of genes and a cause of cancer development. Here we present evidence that an orphan gene, FAM8A1 (family with sequence similarity 8), was captured by a retrovirus, followed by multiple retrotransposition events, during primate evolution between 45 and 58 million years ago. This represents the first record of cellular mRNA transduction in humans. The human gene is localized on chromosome 6p23 with five related pseudogenes (FAM8A2P-A6P), each inserted within a human endogenous retrovirus (HERV). Only the functional FAM8A1 gene is expressed and displays a ubiquitous mRNA and a testis-specific transcript present in the haploid phase of spermatogenesis. The structural features of the FAM8A1 pseudogenes include two short sequences of similarity between the FAM8A1 mRNA and the HERV sequences at both the 5' and 3' integration sites. These hallmarks suggest an alternative model to account for the capture of FAM8A1 cellular mRNA by HERV-K, involving illegitimate recombination events at the two sites of sequence similarity during reverse transcription. Unlike previous models, which assume at least one step of retroviral integration in the genome, our model is consistent with in vitro observations showing that multiple template switches occur among packaged viral transcripts. This leads to the speculation that, in some cases, cellular mRNAs may have been captured through similar processes involved in the retroviral life cycle.


Asunto(s)
Retrovirus Endógenos/genética , Evolución Molecular , Primates/genética , Proteínas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Bovinos , Pollos , ADN/química , ADN/genética , ADN Complementario/química , ADN Complementario/genética , Femenino , Conversión Génica , Expresión Génica , Transferencia de Gen Horizontal , Humanos , Masculino , Proteínas de la Membrana , Ratones , Datos de Secuencia Molecular , Mutación , Filogenia , Seudogenes/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Distribución Tisular , Tortugas , Xenopus
18.
J Anat ; 198(Pt 4): 473-9, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11327209

RESUMEN

Motor neurons are lost during embryonic development, but it remains controversial whether motor neuron cell death occurs during postnatal life. In this study we investigated the effect of postnatal maturation on the number of intact spinal motor neurons in the rat using retrograde labelling with model-based counting, and an unbiased stereological counting technique. To determine the number of motor neurons innervating a specific forelimb muscle in rats of different postnatal ages FluoroGold was injected into the flexor carpi radialis. Before postnatal day 21 there were higher numbers of retrogradely labelled motor neurons than in adult rats, suggesting a 'loss' with postnatal maturation. This loss may be attributed to tracer diffusion to adjacent muscles and to the permeability of the muscle spindle capsule in younger animals. To obtain an unbiased estimate of the number of motor neurons in the C7 and C8 segments of the postnatal rat cervical spinal cord the fractionator/optical disector counting technique was used. This method did not show a loss of spinal motor neurons between birth and adulthood. The main conclusion from this study is that there is no loss of spinal motor neurons during postnatal maturation.


Asunto(s)
Animales Recién Nacidos/crecimiento & desarrollo , Neuronas Motoras/citología , Médula Espinal/crecimiento & desarrollo , Animales , Recuento de Células , Vértebras Cervicales , Miembro Anterior , Músculo Esquelético/inervación , Ratas , Ratas Wistar , Médula Espinal/citología
19.
Genomics ; 74(1): 36-44, 2001 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-11374900

RESUMEN

Several studies have reported significant linkage for schizophrenia on 6p23, with a maximum lod score between D6S274 and D6S285. In this paper, we present a new human kinesin gene localized in this 2-cM interval. This gene, termed KIF13A, belongs to the unc-104/KIF1A kinesin subfamily and represents the orthologue of Drosophila kinesin-73. Several alternative transcripts are differentially expressed in human tissues, probably reflecting differences in cargo binding and transport of corresponding proteins. During early mouse development, its homologue (Kif13A) is expressed essentially in the central nervous system. In Caenorhabditis elegans, the unc-104 gene is involved in axonal anterograde transport, and null mutants present several behavioral defects. The putative function and genomic localization of KIF13A make this gene an interesting candidate for genetic predisposition to schizophrenia. We provide sequences of 20 single-nucleotide polymorphisms localized within KIF13A to test for association studies between this gene and schizophrenia.


Asunto(s)
Proteínas Portadoras/genética , Proteínas de Drosophila , Predisposición Genética a la Enfermedad/genética , Cinesinas/genética , Proteínas del Tejido Nervioso/genética , Esquizofrenia/genética , Secuencia de Aminoácidos , Animales , Clonación Molecular , ADN Complementario/química , ADN Complementario/genética , Bases de Datos Factuales , Embrión de Mamíferos/metabolismo , Femenino , Regulación del Desarrollo de la Expresión Génica , Humanos , Hibridación in Situ , Masculino , Ratones , Datos de Secuencia Molecular , Filogenia , Polimorfismo de Nucleótido Simple , ARN Mensajero/genética , ARN Mensajero/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Distribución Tisular
20.
J Nutr ; 128(2): 152-7, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9446836

RESUMEN

The reaction of superoxide (a reactive oxygen species) and nitric oxide (one of the nitrogen oxides with numerous biological functions) results in the production of peroxynitrite. The characteristics of oxidation of alpha-tocopherol (vitamin E) in synaptosomes (nerve ending particles) and mitochondria by peroxynitrite were studied. The subcellular fractions were isolated from brain hemispheres of 4-month-old male Fischer 344 rats by standard centrifugation procedures involving Ficoll gradients. Peroxynitrite treatment oxidized alpha-tocopherol in <5 s. This reaction was selective because another membrane component, cholesterol, was not oxidized at the same time, as observed in our previous studies. Mitochondrial alpha-tocopherol was more susceptible to peroxynitrite-induced oxidation than synaptosomal tocopherol. Measurable and significant (P < 0.05) oxidation of tocopherol occurred when mitochondria or synaptosomes were incubated with peroxynitrite in concentrations as low as 5 or 10 micromol/L, respectively. The oxidation could be readily monitored by estimating the production of tocopherolquinone. Oxidation of tocopherol induced by ferrous iron and ascorbate was much slower and the yield of tocopherolquinone lower than by peroxynitrite. The fast and selective oxidation of alpha-tocopherol by peroxynitrite suggests that vitamin E may play an important role in preventing membrane oxidation induced by peroxynitrite. Literature reports indicate the existence of threshold concentrations of tocopherol below which functional alterations occur. Tocopherol oxidation by peroxynitrite could reduce tocopherol concentrations in tissues and subcellular structures to these threshold levels by different concentrations of peroxynitrite. Hence the sensitivity of tissues to peroxynitrite could vary over a wide range.


Asunto(s)
Encéfalo/efectos de los fármacos , Nitratos/farmacología , Oxidantes/farmacología , Vitamina E/metabolismo , Animales , Antioxidantes/metabolismo , Encéfalo/metabolismo , Células Cultivadas , Relación Dosis-Respuesta a Droga , Masculino , Oxidación-Reducción , Ratas , Ratas Endogámicas F344 , Sinaptosomas/efectos de los fármacos , Sinaptosomas/metabolismo , Vitamina E/análogos & derivados
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