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Central thalamic deep brain stimulation (CT-DBS) is an investigational therapy to treat enduring cognitive dysfunctions in structurally brain injured (SBI) patients. However, the mechanisms of CT-DBS that promote restoration of cognitive functions are unknown, and the heterogeneous etiology and recovery profiles of SBI patients contribute to variable outcomes when using conventional DBS strategies,which may result in off-target effects due to activation of multiple pathways. To disambiguate the effects of stimulation of two adjacent thalamic pathways, we modeled and experimentally compared conventional and novel 'field-shaping' methods of CT-DBS within the central thalamus of healthy non-human primates (NHP) as they performed visuomotor tasks. We show that selective activation of the medial dorsal thalamic tegmental tract (DTTm), but not of the adjacent centromedian-parafascicularis (CM-Pf) pathway, results in robust behavioral facilitation. Our predictive modeling approach in healthy NHPs directly informs ongoing and future clinical investigations of conventional and novel methods of CT-DBS for treating cognitive dysfunctions in SBI patients, for whom no therapy currently exists.
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Comportamento Animal , Mapeamento Encefálico , Estimulação Encefálica Profunda/métodos , Eletrodos Implantados , Imageamento por Ressonância Magnética/métodos , Tálamo/diagnóstico por imagem , Tálamo/fisiologia , Animais , Biofísica , Cognição/fisiologia , Análise de Elementos Finitos , Macaca mulatta , Masculino , Análise Multivariada , Vias Neurais , Análise de Regressão , Visão OcularRESUMO
Becker muscular dystrophy (BMD) is the milder allelic variant of Duchenne muscular dystrophy, with higher dystrophin levels. To anticipate on results of interventions targeting dystrophin expression it is important to know the natural variation of dystrophin expression between different muscles and over time. Dystrophin was quantified using capillary Western immunoassay (Wes) in the anterior tibial (TA) muscle of 37 BMD patients. Variability was studied using two samples from the same TA biopsy site in nine patients, assessing nine longitudinal TA biopsies, and eight simultaneously obtained vastus lateralis (VL) muscle biopsies. Measurements were performed in duplicate with two primary antibodies. Baseline dystrophin levels were correlated to longitudinal muscle strength and functional outcomes. Results showed low technical variability and high precision for both antibodies. Dystrophin TA levels ranged from 4.8 to 97.7%, remained stable over a 3-5 year period, and did not correlate with changes in longitudinal muscle function. Dystrophin levels were comparable between TA and VL muscles. Intra-muscle biopsy variability was low (5.2% and 11.4% of the total variability of the two antibodies). These observations are relevant for the design of clinical trials targeting dystrophin production, and may urge the need for other biomarkers or surrogate endpoints.
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Biomarcadores , Distrofina/metabolismo , Expressão Gênica , Imunoensaio , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/metabolismo , Adolescente , Adulto , Idoso , Biópsia , Criança , Pré-Escolar , Distrofina/genética , Humanos , Imunoensaio/métodos , Lactente , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Distrofia Muscular de Duchenne/diagnóstico , Mutação , Adulto JovemRESUMO
OBJECTIVE: Becker muscular dystrophy (BMD) is characterised by broad clinical variability. Ongoing studies exploring dystrophin restoration in Duchenne muscular dystrophy ask for better understanding of the relation between dystrophin levels and disease severity. We studied this relation in BMD patients with varying mutations, including a large subset with an exon 45-47 deletion. METHODS: Dystrophin was quantified by western blot analyses in a fresh muscle biopsy of the anterior tibial muscle. Disease severity was assessed using quantitative muscle strength measurements and functional disability scoring. MRI of the leg was performed in a subgroup to detect fatty infiltration. RESULTS: 33 BMD patients participated. No linear relation was found between dystrophin levels (range 3%-78%) and muscle strength or age at different disease milestones, in both the whole group and the subgroup of exon 45-47 deleted patients. However, patients with less than 10% dystrophin all showed a severe disease course. No relation was found between disease severity and age when analysing the whole group. By contrast, in the exon 45-47 deleted subgroup, muscle strength and levels of fatty infiltration were significantly correlated with patients' age. CONCLUSIONS: Our study shows that dystrophin levels appear not to be a major determinant of disease severity in BMD, as long as it is above approximately 10%. A significant relation between age and disease course was only found in the exon 45-47 deletion subgroup. This suggests that at higher dystrophin levels, the disease course depends more on the mutation site than on the amount of the dystrophin protein produced.
Assuntos
Distrofina/análise , Distrofia Muscular de Duchenne/patologia , Adulto , Fatores Etários , Idoso , Western Blotting , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Força Muscular , Músculo Esquelético/química , Músculo Esquelético/patologia , Índice de Gravidade de Doença , Adulto JovemRESUMO
Recently, missense and truncating mutations in the gene PCDH19 have been reported to cause female-restricted epilepsy with mental retardation (EFMR). EFMR (MIM#300088) is an X-linked disorder characterized by early onset seizures and intellectual disability (ID). Interestingly, unlike typical X-linked mode of inheritance, the phenotype is restricted to females, and males are unaffected carriers. PCDH19 is highly expressed in brain, and the encoded protein belongs to the cadherin superfamily. Here we report two unrelated female patients with deletions spanning PCDH19 identified by copy number variation (CNV) analysis and validated by qPCR. In one, we have identified a 3 Mb interstitial deletion at Xq21.33-q22.1 which spans PCDH19, LOC442459 & TNMD. This patient had her first seizure at 8 months old, and also has ID and aggressive behavior. In another female patient we identified a de novo 603 kb heterozygous deletion in a female patient with fits (since 1 year of age), ID, hyperactivity and aggressive behavior. The deletion spans the entire PCDH19 gene (also TNMD, SRPX2, TSPAN6 and SYTL4). In conclusion, our results suggest that deletions at PCDH19 also cause EFMR.
Assuntos
Anormalidades Múltiplas/genética , Caderinas/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Deficiência Intelectual/genética , Convulsões/genética , Deleção de Sequência/genética , Variações do Número de Cópias de DNA , Feminino , Humanos , Análise em Microsséries , Protocaderinas , Reação em Cadeia da Polimerase em Tempo Real , Inativação do Cromossomo X/genéticaRESUMO
Autoimmune polyglandular syndrome (APS) type 2 is defined by the manifestation of at least two autoimmune endocrine diseases. Only few data exist on genetic associations of APS type 2. In this controlled study, 98 patients with APS type 2, 96 patients with type 1 diabetes (T1D), and 92 patients with autoimmune thyroid disease, both as a single autoimmune endocrinopathy, were tested for association with alleles of the human leukocyte antigen (HLA) class II loci DRB1, DQA1, and DQB1. Patients with APS type 2 had significantly more often the alleles DRB1*03 (P(c) < 0.0001), DRB1*04 (P(c) < 0.000005), DQA1*03 (P(c) < 0.0001), and DQB1*02 (P(c) < 0.05), when compared with controls. Less frequent in APS were DRB1*15 (P(c) < 0.05), DQA1*01 (P(c) < 0.0005), and DQB1*05 (P(c) < 0.005). With regard to frequency and linkage of these alleles, the susceptible haplotypes DRB1*0301-DQA1*0501-DQB1*0201 and DRB1*0401/04-DQA1*0301-DQB1*0302 were deduced. Protective haplotypes in this study were DRB1*1501-DQA1*0102-DQB1*0602 and DRB1*0101-DQA1*0101-DQB1*0501. Comparing APS patients with vs without AD, no significant differences regarding HLA class II alleles were noted in our collective. Patients with T1D as a singular disease had the same susceptible and protective HLA alleles and haplotypes. The prevalence of DRB1*03 and DRB1*04 in APS patients was not because of the presence of diabetes, as the APS type 2 patients without diabetes had the same allele distribution. In conclusion, these data suggest a common immunogenetic pathomechanism for T1D and APS type 2, which might be different from the immunogenetic pathomechanism of other autoimmune endocrine disease.
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Alelos , Diabetes Mellitus Tipo 1/genética , Frequência do Gene/genética , Antígenos HLA-D/genética , Poliendocrinopatias Autoimunes/genética , Adulto , Diabetes Mellitus Tipo 1/imunologia , Feminino , Frequência do Gene/imunologia , Antígenos HLA-D/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Poliendocrinopatias Autoimunes/imunologiaRESUMO
BACKGROUND: One year after stoma formation with an open technique, the rate of parastomal hernia is almost 50%. The herniation rate can be reduced to 10% with the use of a prophylactic mesh in a sublay position. For stomas formed with a laparoscopic technique, a surgical method with the use of prophylactic mesh should be sought. METHODS: Patients with a sigmoidostomy created with a laparoscopic technique were provided with a prophylactic large-pore, low-weight mesh in a sublay position. Follow-up examination was carried out after at least 12 months. RESULTS: Between March 2003 and May 2007, a sigmoidostomy was created in 25 patients. The patients' mean age was 65 years (range 31-89), the mean body mass index was 26 (range 21-32) and 15 were female. One stoma necrosis and two minor wound infections occurred. Parastomal hernia was present in 3 of 20 patients (15%) available for follow-up examination after 11-31 months (mean 19). No fistulas or strictures had developed. No mesh infection was noted and no mesh was removed. CONCLUSION: In laparoscopic stoma formation, a prophylactic large-pore, low-weight mesh in a sublay position is an easy and safe procedure associated with a low rate of parastomal hernia.
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Enterostomia/efeitos adversos , Hérnia Ventral/etiologia , Laparoscopia/efeitos adversos , Telas Cirúrgicas/efeitos adversos , Estomas Cirúrgicos/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Hérnia Ventral/prevenção & controle , Hérnia Ventral/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Estudos RetrospectivosRESUMO
Antisense oligonucleotides (AONs) can be used to correct the disrupted reading frame of Duchenne muscular dystophy patients (DMD). We have a collection of 121 AONs, of which 79 are effective in inducing the specific skipping of 38 out of the 79 different DMD exons. All AONs are located within exons and were hypothesized to act by steric hindrance of serine-arginine rich (SR) protein binding to exonic splicing enhancer (ESE) sites. Indeed, retrospective in silico analysis of effective versus ineffective AONs revealed that the efficacy of AONs is correlated to the presence of putative ESE sites (as predicted by the ESEfinder and RESCUE-ESE software). ESE predicting software programs are thus valuable tools for the optimization of exon-internal antisense target sequences.
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Distrofina/genética , Distrofia Muscular de Duchenne/tratamento farmacológico , Oligonucleotídeos Antissenso/farmacologia , Splicing de RNA/efeitos dos fármacos , Elementos Facilitadores Genéticos , Éxons , Humanos , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/uso terapêutico , Sítios de Splice de RNA , SoftwareRESUMO
The detection of duplications in Duchenne (DMD)/Becker Muscular Dystrophy (BMD) has long been a neglected issue. However, recent technological advancements have significantly simplified screening for such rearrangements. We report here the detection and analysis of 118 duplications in the DMD gene of DMD/BMD patients. In an unselected patient series the duplication frequency was 7%. In patients already screened for deletions and point mutations, duplications were detected in 87% of cases. There were four complex, noncontiguous rearrangements, with two also involving a partial triplication. In one of the few cases where RNA was analyzed, a seemingly contiguous duplication turned out to be a duplication/deletion case generating a transcript with an unexpected single-exon deletion and an initially undetected duplication. These findings indicate that for clinical diagnosis, duplications should be treated with special care, and without further analysis the reading frame rule should not be applied. As with deletions, duplications occur nonrandomly but with a dramatically different distribution. Duplication frequency is highest near the 5' end of the gene, with a duplication of exon 2 being the single most common duplication identified. Analysis of the extent of 11 exon 2 duplications revealed two intron 2 recombination hotspots. Sequencing four of the breakpoints showed that they did not arise from unequal sister chromatid exchange, but more likely from synthesis-dependent nonhomologous end joining. There appear to be fundamental differences therefore in the origin of deletions and duplications in the DMD gene.
Assuntos
Distrofina/genética , Duplicação Gênica , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/genética , Estudos de Coortes , Testes Genéticos/métodos , HumanosRESUMO
Although the prevalence of obesity in Sweden still is low in an international perspective, the development during the last decades is alarming in adults, adolescents and children alike. The prevalence of obesity [body mass index (BMI) > 30 kg m-2] in adults has doubled during the last two decades and is now approximately 10% in both men and women, according to estimates based on self-reported BMI from repeated random samples of the population. However, prevalence estimates based on measured BMI from the WHO MONICA study indicate that the self-reported data result in underestimates. In military conscripts, the prevalence of obesity (BMI > 30 kg m-2) almost quadrupled to 3.2% from 1971 to 1995, while the overweight fraction (BMI > 25 kg m-2) more than doubled to 16.3%. The development in younger age groups seems to be similar; the prevalence of overweight [International Obesity Task Force (IOTF)/Cole] in children aged 10 years in Gothenburg has doubled to 18% (2.9% obese) during the last decade, and similar figures have been reported in other studies. However, most reports on childhood overweight stem from the larger metropolitan areas, and hence may be underestimates because of the urban-rural influence on obesity-status. Recent data from non-urban areas in the northern part of Sweden estimate the prevalence of overweight (BMI > 20 kg m-2) in 10-year-olds to above 30%. In the most comprehensive study in children, including both rural and urban areas, BMI was measured among all children aged 10 years (n = 5517; 92.7% of the population) in the county of Ostergotland, and the prevalence of overweight (IOTF/Cole) was 22% in both boys and girls, of which 4% and 5% were obese respectively.
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Obesidade/epidemiologia , Sobrepeso , Adolescente , Adulto , Distribuição por Idade , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Suécia/epidemiologiaRESUMO
Electronic systems for communicable diseases surveillance enhance quality by simplifying reporting, improving completeness, and increasing timeliness. In this article we outline the ideas and technologies behind SmiNet-2, a new comprehensive regional/national system for communicable disease surveillance in Sweden. The system allows for reporting from physicians (web form) and laboratories (direct from lab data system) over the internet. Using a unique personal identification number, SmiNet-2 automatically merges clinical and laboratory notifications to case records. Privileged users, at national and county level, work against a common central server containing all notifications and case records. In addition, SmiNet-2 has separate county servers with tools for outbreak investigations, contact tracing and case management. SmiNet-2 was first used in September 2004. Individual counties receive up to 90% of all notifications electronically. In its first year, SmiNet-2 received 54 980 clinical notifications and 32 765 laboratory notifications, which generated 58 891 case records. Since most clinicians in Sweden have easy access to the internet, a general web-based reporting has been feasible, and it is anticipated that within a few years all reporting to SmiNet-2 will be over the internet. In this context, some of the major advantages of SmiNet-2 when compared with other systems are timeliness in the dataflow (up to national level), the full integration of clinical and laboratory notifications, and the capability to handle more than 50 diseases with tailor-made notification forms within one single system.
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Using a Before/During/After sampling protocol, the effects of the Le Havre harbour extension, which was started at the end of 2001, on the macrobenthic and suprabenthic communities in the eastern Bay of Seine (English Channel) were examined. As the construction phase has not yet been completed, the results presented here reflect only the data collected before and during the operations (September 2000 and 2002 for benthos sampling and March 2001, September 2001, October 2002 and March 2003 for suprabenthos sampling). Although bio-sedimentary changes did occur at the mouth of the Seine river, an analysis of benthic assemblages reveals that the dredging and construction operations do not seem to have influenced assemblage structure or the spatial distribution of organisms. Comparisons of the suprabenthic assemblages at each sampling date indicate that seasonal dynamics was mainly responsible for determining species distribution. We conclude that, 1 year into the harbour management plan, the observed changes in benthic and suprabenthic assemblage abundance do not exceed the range of spatial variability that exists naturally in the Seine estuary. Despite this compensatory actions designed to protect the aquatic habitats and to preserve a sustainable and healthy ecosystem have been added to the infrastructure development plan.
Assuntos
Ecossistema , Monitoramento Ambiental/estatística & dados numéricos , Sedimentos Geológicos/análise , Invertebrados/crescimento & desenvolvimento , Adaptação Fisiológica , Animais , Coleta de Dados , Arquitetura de Instituições de Saúde , França , Invertebrados/fisiologia , Dinâmica PopulacionalRESUMO
INTRODUCTION: Dermal exposure to hydrofluoric acid (HF) may cause severe burns and systemic toxicity. Hexafluorine (Prevor, France) is a product marketed as an emergency decontamination fluid for HF skin and eye exposures. Documentation concerning Hexafluorine is scanty, and a recent study indicates that its ability to reduce HF burns is at most equal to that of water. OBJECTIVE: The present study was conducted to evaluate Hexafluorine's capacity to reduce HF-induced systemic toxicity. METHODS: Sprague Dawley rats were anesthetized, catheterized in the left femoral artery, and shaved on their back. A filter paper (3.5 x 6 cm) was soaked in 50% HF and applied on the back of each rat for 3 min. Thirty seconds after removal of the paper, a 3-min rinsing with either 500 mL Hexafluorine (group H), 500 mL water (group W), or 500 mL water followed by a single application of 2.5% calcium gluconate gel (group Ca) was carried out. Blood samples were analyzed for ionized calcium and potassium (before injury and 1, 2, 3, and 4 h after) and also for ionized fluoride (1, 2, and 4 h after injury). RESULTS: The animals developed hypocalcemia, hyperkalemia, and hyperfluoridemia after the HF exposure. The only significant difference observed among the groups was in serum potassium at 1 h between group Ca and group W. However, there was a constant trend toward milder hypocalcemia and less pronounced hyperkalemia in group Ca compared to the other groups. There were no differences in the electrolyte disturbances between the Hexafluorine-treated animals and those treated with water only. Five of 39 animals died before completion of the experiment as a result of the HF exposure, one from group Ca and two from each of the other two groups. CONCLUSION: In this experimental study, decontamination with Hexafluorine was not more effective than water rinsing in reducing electrolyte disturbances caused by dermal exposure to hydrofluoric acid.
Assuntos
Queimaduras Químicas/terapia , Cáusticos/toxicidade , Compostos de Flúor/administração & dosagem , Ácido Fluorídrico/toxicidade , Animais , Queimaduras Químicas/sangue , Queimaduras Químicas/patologia , Cálcio/sangue , Modelos Animais de Doenças , Fluoretos/sangue , Masculino , Potássio/sangue , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Irrigação TerapêuticaRESUMO
As small molecule drugs for Duchenne muscular dystrophy (DMD), antisense oligonucleotides (AONs) have been shown to restore the disrupted reading frame of DMD transcripts by inducing specific exon skipping. This allows the synthesis of largely functional Becker muscular dystrophy (BMD)-like dystrophins and potential conversion of severe DMD into milder BMD phenotypes. Thus far we have used 2'-O-methyl phosphorothioate (2OMePS) AONs. Here, we assessed the skipping efficiencies of different AON analogs containing morpholino-phosphorodiamidate, locked nucleic acid (LNA) or peptide nucleic acid (PNA) backbones. In contrast to PNAs and morpholinos, LNAs have not yet been tested as splice modulators. Compared to the most effective 2OMePS AON directed at exon 46, the LNA induced higher skipping levels in myotubes from a human control (85 versus 20%) and an exon 45 deletion DMD patient (98 versus 75%). The morpholino-induced skipping levels were only 5-6%, whereas the PNA appeared to be ineffective. Further comparative analysis of LNA and 2OMePS AONs containing up to three mismatches revealed that LNAs, while inducing higher skipping efficiencies, show much less sequence specificity. This limitation increases the risk of adverse effects elsewhere in the human genome. Awaiting further improvements in oligochemistry, we thus consider 2OMePS AONs currently the most favorable compounds, at least for targeted DMD exon 46 skipping.
Assuntos
Terapia Genética/métodos , Células Musculares/metabolismo , Distrofia Muscular de Duchenne/terapia , Oligonucleotídeos Antissenso/genética , Sequência de Bases , Estudos de Casos e Controles , Células Cultivadas , Distrofina/genética , Ensaio de Desvio de Mobilidade Eletroforética , Éxons , Dosagem de Genes , Humanos , Dados de Sequência Molecular , Fibras Musculares Esqueléticas/metabolismo , Distrofia Muscular de Duchenne/metabolismo , Oligonucleotídeos , Oligonucleotídeos Antissenso/administração & dosagem , Alinhamento de SequênciaRESUMO
Extra-thyroidal thyrotropin (TSH) receptors (TSHRs) have been demonstrated in several tissues and cells, including human and rat osteosarcoma cell lines. We have explored whether human TSHR (hTSHRs) also are present in primary cultures of human osteoblast-like (hOB) cells. [(125) I]TSH binding was limited in hOB cells, but somewhat higher in UMR 106-01 cells and considerably higher in hTSHR-transfected CHO cells. In hOB cells, the basal intracellular cAMP levels increased 282% after stimulation with 10 U/L TSH. In the hTSHR-transfected CHO cells, the cAMP increase was 3030% in response to 10 U/L TSH and 1240% after 1 U/L TSH. Free cytoplasmic calcium did not change in response to TSH in hOB cells. HTSHR mRNA was detected in hOB cells from 3/4 bone by reverse transcriptase polymerase chain reaction RT-PCR and nucleotide sequencing HTSHR mRNA, but could not be demonstrated with the RNase protection technique in hOB cells from 5 different donors. In conclusion, even after the use of several methods, we have found only weak evidence for expression and presence of functionally active hTSHR in hOB cells. Given the low level of expression, specific binding and cAMP signaling, we suggest that it is unlikely that circulating TSH plays a physiological role for bone metabolism mediated through osteoblasts.
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Osso e Ossos/metabolismo , Osteoblastos/metabolismo , Receptores da Tireotropina/metabolismo , Animais , Sequência de Bases , Células CHO , Cálcio/metabolismo , Células Cultivadas , Cricetinae , Cricetulus , AMP Cíclico/metabolismo , Humanos , RNA Mensageiro/análise , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tireotropina/metabolismo , TransfecçãoRESUMO
Since targeting of recombinant adenovirus vectors to defined cell types in vivo is a major challenge in gene therapy and vaccinology, we explored the natural diversity in human adenovirus tissue tropism. Hereto, we constructed a library of Ad5 vectors carrying fibers from other human serotypes. From this library, we identified vectors that efficiently infect human cells that are important for diverse gene therapy approaches and for induction of immunity. For several medical applications (prenatal diagnosis, artificial bone, vaccination, and cardiovascular disease), we demonstrate the applicability of these novel vectors. In addition, screening cell types derived from different species revealed that cellular receptors for human subgroup B adenoviruses are not conserved between rodents and primates. These results provide a rationale for utilizing elements of human adenovirus serotypes to generate chimeric vectors that improve our knowledge concerning adenovirus biology and widen the therapeutic window for vaccination and many different gene transfer applications.
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Adenovírus Humanos/classificação , Adenovírus Humanos/genética , Proteínas do Capsídeo , Capsídeo/genética , Doenças Cardiovasculares/prevenção & controle , Terapia Genética/métodos , Animais , Osso e Ossos , Linhagem Celular , Técnicas de Transferência de Genes , Vetores Genéticos , Humanos , Camundongos , Técnicas de Cultura de Órgãos , Diagnóstico Pré-Natal , Ratos , Proteínas Recombinantes de Fusão , Sorotipagem , Engenharia Tecidual , Vacinas ViraisRESUMO
Here we present evidence for spontaneous and long-lasting regeneration of CNS axons after spinal cord lesions in adult rats. The length of 200 kD neurofilament (NF)-immunolabeled axons was estimated after photochemically induced ischemic spinal cord lesions using a stereological tool. The total length of all NF-immunolabeled axons within the lesion cavities was increased 6- to 10-fold at 5, 10, and 15 wk post-lesion compared with 1 wk post-surgery. In ultrastructural studies we found the putatively regenerating axons within the lesion to be associated either with oligodendrocytes or Schwann cells, while other fibers were unmyelinated. Immunohistochemistry demonstrated that some of the regenerated fibers were tyrosine hydroxylase- or serotonin-immunoreactive, indicating a central origin. These findings suggest that there is a considerable amount of spontaneous regeneration after spinal cord lesions in rodents and that the fibers remain several months after injury. The findings of tyrosine hydroxylase- and serotonin-immunoreactivity in the axons suggest that descending central fibers contribute to this endogenous repair of ischemic spinal cord injury.
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Axônios/fisiologia , Proteínas de Neurofilamentos/metabolismo , Regeneração/fisiologia , Traumatismos da Medula Espinal/fisiopatologia , Medula Espinal/patologia , Animais , Axônios/metabolismo , Feminino , Humanos , Microscopia de Fluorescência , Oligodendroglia/metabolismo , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Células de Schwann/metabolismo , Células de Schwann/ultraestrutura , Serotonina/metabolismo , Medula Espinal/metabolismo , Medula Espinal/ultraestruturaRESUMO
Striatal 6-[18F]fluoro-L-DOPA (FDOPA) kinetic rate constants were measured by positron emission tomography (PET) in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated squirrel monkeys. After scanning, stereological counts of dopaminergic neurons were done in substantia nigra, and dopamine (DA) and metabolite concentrations were determined in the caudate, putamen, and substantia nigra. Graded doses of MPTP produced animals with mild to moderate reductions (10-35%) in dopaminergic neurons, where the percent of cell loss was proportional to the amount of MPTP given. Striatal DA and metabolite concentrations were relatively unchanged in animals given 1.0 and 1.5 mg/kg of MPTP, but were significantly reduced after 2.0 mg/kg of MPTP. All animals injected with a single dose of MPTP showed no overt signs of parkinsonism. In contrast, DA and metabolite concentrations in the substantia nigra were significantly reduced for all MPTP-treated animals. Reduction of dopaminergic indices in the substantia nigra did not parallel reductions in the striatum, indicating differential sensitivity of the nigrostriatal pathway to the neurotoxic effects of MPTP. The percent change in FDOPA uptake (Ki) and decarboyxlation (k3) after MPTP showed significant positive correlations to striatal DA levels, but not to the number of dopaminergic neurons. This suggests that FDOPA is a good index of striatal DA levels.
Assuntos
Corpo Estriado/patologia , Di-Hidroxifenilalanina/análogos & derivados , Dopamina/deficiência , Transtornos Parkinsonianos/metabolismo , Substância Negra/patologia , Tomografia Computadorizada de Emissão , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Animais , Corpo Estriado/metabolismo , Modelos Animais de Doenças , Feminino , Radioisótopos de Flúor , Masculino , Vias Neurais , Neurotoxinas , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/patologia , Saimiri , Substância Negra/metabolismoRESUMO
Due to frame-shifting mutations in the DMD gene that cause dystrophin deficiency, Duchenne muscular dystrophy (DMD) patients suffer from lethal muscle degeneration. In contrast, mutations in the allelic Becker muscular dystrophy (BMD) do not disrupt the translational reading frame, resulting in a less severe phenotype. In this study, we explored a genetic therapy aimed at restoring the reading frame in muscle cells from DMD patients through targeted modulation of dystrophin pre-mRNA splicing. Considering that exon 45 is the single most frequently deleted exon in DMD, whereas exon (45+46) deletions cause only a mild form of BMD, we set up an antisense-based system to induce exon 46 skipping from the transcript in cultured myotubes of both mouse and human origin. In myotube cultures from two unrelated DMD patients carrying an exon 45 deletion, the induced skipping of exon 46 in only approximately 15% of the mRNA led to normal amounts of properly localized dystrophin in at least 75% of myotubes. Our results provide first evidence of highly effective restoration of dystrophin expression from the endogenous gene in DMD patient-derived muscle cells. This strategy may be applicable to not only >65% of DMD mutations, but also many other genetic diseases.
Assuntos
Distrofina/biossíntese , Distrofina/genética , Éxons , Deleção de Genes , Músculos/citologia , Distrofia Muscular de Duchenne/genética , Oligonucleotídeos Antissenso , Alelos , Animais , Sequência de Bases , Linhagem Celular , Humanos , Imuno-Histoquímica , Camundongos , Microscopia de Fluorescência , Modelos Genéticos , Dados de Sequência Molecular , Músculos/patologia , Oligonucleotídeos Antissenso/farmacologia , Fenótipo , Biossíntese de Proteínas , RNA/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Fatores de Tempo , TransfecçãoRESUMO
The calcium flow inhibitor, nimodipine, has been shown to promote motor neuron survival in the facial nucleus after intracranial facial nerve transection. However, it has not been known whether the neuroprotective effects primarily involve survival of nerve cell bodies or outgrowth and/or myelination of nerve fibers. Here, we studied the effects of nimodipine in a different injury model in which the facial nerve was unilaterally crushed intracranially. This lesion caused complete anterograde degeneration and partial retrograde degeneration that were studied with a combination of several stereological methods. Nimodipine did not attenuate the modest lesion-induced neuronal loss (13%) but accelerated the time course of functional recovery and axonal regrowth, inducing increased numbers and sizes of myelinated axons in the facial nerve. It is interesting to note that nimodipine also enlarged the axons and the myelin sheaths in the nonlesioned facial nerve, which points to the possibility of using this substance for new clinical applications to promote axonal growth and remyelination.
Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Traumatismos do Nervo Facial/tratamento farmacológico , Regeneração Nervosa/efeitos dos fármacos , Nimodipina/farmacologia , Animais , Anticorpos , Canais de Cálcio/fisiologia , Canais de Cálcio Tipo L/análise , Canais de Cálcio Tipo L/imunologia , Contagem de Células , Traumatismos do Nervo Facial/fisiopatologia , Imuno-Histoquímica , Masculino , Neurônios Motores/química , Neurônios Motores/fisiologia , Neurônios Motores/ultraestrutura , Movimento/fisiologia , Compressão Nervosa , Fibras Nervosas Mielinizadas/fisiologia , Ratos , Ratos Sprague-Dawley , Vibrissas/inervação , Vibrissas/fisiologiaRESUMO
Novel beta-sheet-forming peptide 33-mers, betapep peptides, have been designed by using a combination approach employing basic folding principles and incorporating short sequences from the beta-sheet domains of anti-angiogenic proteins. One of these designed peptides (betapep-25), named anginex, was observed to be potently anti-angiogenic. Anginex specifically inhibits vascular endothelial cell proliferation and induces apoptosis in these cells, as shown by flow-cytometric detection of sub-diploid cells, TUNEL (terminal deoxyribonucleotidyl transferase-mediated dUTP-nick-end labelling) analysis and cell morphology. Anginex also inhibits endothelial cell adhesion to and migration on different extracellular matrix components. Inhibition of angiogenesis in vitro is demonstrated in the sprout-formation assay and in vivo in the chick embryo chorio-allantoic membrane angiogenesis assay. Comparison of active and inactive betapep sequences allows structure-function relationships to be deduced. Five hydrophobic residues and two lysines appear to be crucial to activity. This is the first report of a designed peptide having a well-defined biological function as a novel cytokine, which may be an effective anti-angiogenic agent for therapeutic use against various pathological disorders, such as neoplasia, rheumatoid arthritis, diabetic retinopathy and restenosis.