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1.
Psychol Med ; 48(6): 939-951, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28826414

RESUMO

BACKGROUND: Being breastfed in infancy has been shown to benefit neurodevelopment. However, whether the benefits persist to old age remains unclear. METHODS: We examined the associations between breastfeeding and its duration on cognitive ability in young adulthood and old age, and on aging-related cognitive change over five decades. In total, 931 men from the Helsinki Birth Cohort Study born in 1934-1944 in Finland took the Finnish Defence Forces Basic Intellectual Ability Test (total and verbal, arithmetic and visuospatial subtest scores) twice, at ages 20.2 and 67.9 years, and had data on breastfeeding (yes v. no) and its duration ('never breastfed', 'up to 3', '3 to 6' and '6 or more months'). Linear and mixed model regressions tested the associations. RESULTS: At 20.2 years, breastfed men had higher cognitive ability total and visuospatial subtest scores [mean differences (MDs) ranged between 3.0-3.9, p values < 0.013], and its longer duration predicted higher cognitive ability total and arithmetic and visuospatial subtest scores (MDs ranged between 3.0 and 4.8, p values < 0.039). At 67.9 years, breastfed men had higher total cognitive ability and all subtest scores (MDs ranged between 2.6 and 3.4, p values < 0.044) and its longer duration predicted all cognitive ability scores (MDs ranged between 3.1 and 4.7, p values < 0.050). Verbal subtest scores decreased over five decades in men who were never breastfed or were breastfed for 3 months or less, and increased in those breastfed for longer than 3 months. CONCLUSIONS: Neurodevelopmental advantages of breastfeeding and its longer duration persist into old age, and longer duration of breastfeeding may benefit aging-related change, particularly in verbal reasoning ability.


Assuntos
Aleitamento Materno , Envelhecimento Cognitivo/fisiologia , Envelhecimento Cognitivo/psicologia , Inteligência/fisiologia , Adulto , Idoso , Cognição , Finlândia , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fatores de Tempo , Adulto Jovem
2.
Psychol Med ; 45(5): 985-99, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25191989

RESUMO

BACKGROUND: Late preterm births constitute the majority of preterm births. However, most evidence suggesting that preterm birth predicts the risk of mental disorders comes from studies on earlier preterm births. We examined if late preterm birth predicts the risks of severe mental disorders from early to late adulthood. We also studied whether adulthood mental disorders are associated with post-term birth or with being born small (SGA) or large (LGA) for gestational age, which have been previously associated with psychopathology risk in younger ages. METHOD: Of 12 597 Helsinki Birth Cohort Study participants, born 1934-1944, 664 were born late preterm, 1221 post-term, 287 SGA, and 301 LGA. The diagnoses of mental disorders were identified from national hospital discharge and cause of death registers from 1969 to 2010. In total, 1660 (13.2%) participants had severe mental disorders. RESULTS: Individuals born late preterm did not differ from term-born individuals in their risk of any severe mental disorder. However, men born late preterm had a significantly increased risk of suicide. Post-term birth predicted significantly increased risks of any mental disorder in general and particularly of substance use and anxiety disorders. Individuals born SGA had significantly increased risks of any mental and substance use disorders. Women born LGA had an increased risk of psychotic disorders. CONCLUSIONS: Although men born late preterm had an increased suicide risk, late preterm birth did not exert widespread effects on adult psychopathology. In contrast, the risks of severe mental disorders across adulthood were increased among individuals born SGA and individuals born post-term.


Assuntos
Retardo do Crescimento Fetal/epidemiologia , Macrossomia Fetal/epidemiologia , Transtornos Mentais/epidemiologia , Nascimento Prematuro/epidemiologia , Adulto , Idoso , Estudos de Coortes , Feminino , Finlândia/epidemiologia , Humanos , Recém-Nascido , Criança Pós-Termo , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Masculino , Pessoa de Meia-Idade , Gravidez , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
3.
Theor Appl Genet ; 107(4): 667-78, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12827250

RESUMO

A genetic map of Pinus sylvestris was constructed using ESTP (expressed sequence tag polymorphism) markers and other gene-based markers, AFLP markers and microsatellites. Part of the ESTP markers (40) were developed and mapped earlier in Pinus taeda, and additional markers were generated based on P. sylvestris sequences or sequences from other pine species. The mapping in P. sylvestris was based on 94 F(1) progeny from a cross between plus-tree parents E635C and E1101. AFLP framework maps for the parent trees were first constructed. The ESTP and other gene sequence-based markers were added to the framework maps, as well as five published microsatellite loci. The separate maps were then integrated with the aid of AFLPs segregating in both trees (dominant segregation ratios 3:1) as well as gene markers and microsatellites segregating in both parent trees (segregation ratios 1:1:1:1 or 1:2:1). The integrated map consisted of 12 groups corresponding to the P. taeda linkage groups, and additionally three and six smaller groups for E1101 and E635C, respectively. The number of framework AFLP markers in the integrated map is altogether 194 and the number of gene markers 61. The total length of the integrated map was 1,314 cM. The set of markers developed for P. sylvestris was also added to existing maps of two P. taeda pedigrees. Starting with a mapped marker from one pedigree in the source species resulted in a mapped marker in a pedigree of the other species in more than 40% of the cases, with about equal success in both directions. The maps of the two species are largely colinear, even if the species have diverged more than 70 MYA. Most cases of different locations were probably due to problems in identifying the orthologous members of gene families. These data provide a first ESTP-containing map of P. sylvestris, which can also be used for comparing this species to additional species mapped with the same markers.


Assuntos
Mapeamento Cromossômico , Etiquetas de Sequências Expressas , Pinus sylvestris/genética , Pinus taeda/genética , Sequência de Bases , Primers do DNA/genética , DNA de Plantas/genética , Marcadores Genéticos , Repetições de Microssatélites , Reação em Cadeia da Polimerase , Polimorfismo Genético , Polimorfismo Conformacional de Fita Simples , Especificidade da Espécie
4.
Mol Ecol ; 12(5): 1195-206, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12694283

RESUMO

Forest tree species provide many examples of well-studied adaptive differentiation, where the search for the underlying genes might be possible. In earlier studies and in our common conditions in a greenhouse, northern populations set bud earlier than southern ones. A difference in latitude of origin of one degree corresponded to a change of 1.4 days in number of days to terminal bud set of seedlings. Earlier physiological and ecological genetics work in conifers and other plants have suggested that such variation could be governed by phytochromes. Nucleotide variation was examined at two phytochrome loci (PHYP and PHYO, homologues of the Arabidopsis thaliana PHYB and PHYA, respectively) in three populations: northern Finland, southern Finland and northern Spain. In our samples of 12-15 sequences (2980 and 1156 base pairs at the two loci) we found very low nonsynonymous variation; pi was 0.0003 and 0.0002 at PHYP and PHYO loci, respectively. There was no functional differentiation between populations at the photosensory domains of either locus. The overall silent variation was also low, only 0.0024 for the PHYP locus. The low estimates of silent variation are consistent with the estimated low synonymous substitution rates between Pinus sylvestris and Picea abies at the PHYO locus. Despite the low level of nucleotide variation, haplotypic diversity was relatively high (0.42 and 0.41 for fragments of 1156 nucleotides) at the two loci.


Assuntos
Evolução Molecular , Variação Genética , Haplótipos/genética , Fitocromo/genética , Pinus sylvestris/genética , Adaptação Biológica , Finlândia , Geografia , Reprodução/fisiologia , Espanha
5.
Med Law ; 20(3): 347-53, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11713833

RESUMO

This paper reviews experience in Finland with the operation of a Law protecting patients who have been harmed in the course of bona fide medical treatment. The current provisions of insurance, claims procedures and compensation are described. In the light of initial experience, parts of the original system were modified. Figures demonstrate the changing levels of claims since 1988 and their outcomes.


Assuntos
Seguro Saúde , Responsabilidade Legal , Erros Médicos/legislação & jurisprudência , Programas Nacionais de Saúde/organização & administração , Ferimentos e Lesões/economia , Finlândia , Humanos , Erros Médicos/economia , Modelos Organizacionais
6.
Rev Neurosci ; 12(4): 311-25, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11783717

RESUMO

During recent years, many reports have indicated that in addition to the progressive neuropathology observed in Alzheimer's disease (AD), there are also plasticity-related changes in the AD brain. It is thought that these plastic events are an attempt by the brain either to try to restore structure and function or to compensate for the damage caused by the disease. Alternatively, it is possible that these changes are a part of the disease's pathologic cascade. Here we discuss our recent findings on highly polysialylated neural cell adhesion molecule (PSA-NCAM) and neuronal-expressed calcium-binding proteins in the hippocampus and entorhinal cortex of controls and patients with AD in relation to the other findings which suggest that structural plasticity is an integral part of the disease process of AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Hipocampo/fisiopatologia , Plasticidade Neuronal , Doença de Alzheimer/patologia , Animais , Encéfalo/patologia , Humanos
7.
Biol Psychiatry ; 47(12): 1056-63, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10862805

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) of hippocampal atrophy is a sensitive but not specific method to support the clinical diagnosis of early Alzheimer's disease (AD). We recently described our findings that atrophy of the entorhinal cortex (ERC) in frontotemporal dementia (FTD) is equal to that found in AD but that hippocampal atrophy in FTD is less than that found in AD. The MRI volumes of these structures provide a topographic representation of the region of interest. We hypothesized that two different dementias with distinct histopathologic and clinical features might, in addition to quantitative patterns, display topographically different patterns of atrophy. METHODS: We adopted a morphometric approach to monitor the pattern of atrophy of the hippocampus and the ERC by computing two-dimensional profiles from MRI volumes of the structures in control subjects and patients with FTD and AD. RESULTS: Compared with control subjects, atrophy of the hippocampus in patients with AD was diffuse. In patients with FTD, atrophy of the hippocampus was localized predominantly in the anterior hippocampus, suggesting a different pattern of hippocampal atrophy in FTD compared with AD. The amount and pattern of atrophy of the entorhinal cortex was virtually equal in both demented groups. CONCLUSIONS: This study provides novel data on the nature of medial temporal lobe atrophy in FTD. Morphometric MRI may be a useful technique for characterizing different patterns of atrophy in primary degenerative dementias in vivo.


Assuntos
Doença de Alzheimer/patologia , Demência/patologia , Córtex Entorrinal/patologia , Lobo Frontal/patologia , Hipocampo/patologia , Lobo Temporal/patologia , Idoso , Atrofia/patologia , Demência/psicologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica
8.
Neuroscience ; 96(3): 515-22, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10717432

RESUMO

The present study was designed to investigate the morphology of spiny neurons in the human entorhinal cortex. Coronal entorhinal slices (n = 67; 200 microm thick) were obtained from autopsies of three subjects. Spiny neurons (n = 132) filled with Lucifer Yellow were analysed in different subfields and layers of the entorhinal cortex. Based on the shape of the somata and primary dendritic trees, spiny neurons were divided into four morphological categories; (i) classical pyramidal, (ii) stellate, (iii) modified stellate, and (iv) horizontal tripolar cells. The morphology of filled neurons varied more in different layers than in the different subfields of the entorhinal cortex. In layer II, the majority (81%) of spiny neurons had stellate or modified stellate morphology, but in the rostromedial subfields (olfactory subfield and rostral subfield) there were also horizontal tripolar neurons. Dendritic branches of layer II neurons extended to layer I (94%) and to layer III (83%). Unlike in layer II, most (74%) of the filled neurons in layers III, V and VI were classical pyramidal cells. The majority of pyramidal cells in the superficial portion of layer III had dendrites that extended up to layer II, occupying the space between the neuronal clusters. Some dendrites reached down to the deep portion of layer III. Apical dendrites of layer V and VI pyramidal cells traveled up to the deep portion of layer III.Our data indicate that the morphology of spiny neurons in different layers of the human entorhinal cortex is variable. Vertical extension of dendritic branches to adjacent layers supports the idea that inputs terminating in a specific lamina influence target cells located in various entorhinal layers. There appears to be more overlap in the dendritic fields between superficial layers II and III than between the superficial (II/III) and deep (V/VI) layers, thus supporting the idea of segregation of information flow targeted to the superficial or deep layers in the human entorhinal cortex.


Assuntos
Córtex Entorrinal/citologia , Neurônios/citologia , Corantes Fluorescentes , Humanos , Membranas Intracelulares/ultraestrutura , Isoquinolinas , Microscopia de Fluorescência
9.
Neurosci Lett ; 280(2): 119-22, 2000 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-10686392

RESUMO

Earlier studies have shown elevated levels of tau protein and decreased levels of amyloid beta42 in cerebrospinal fluid (CSF) from patients with Alzheimer's disease (AD). We investigated the concentrations of Abeta42, Abeta40 and tau in CSF from AD patients on the baseline and after follow-up period of 3 years using ELISA assays. There was a significant decrease of Abeta42 (P<0.05) and Abeta40 (P<0.05) levels with time. AD patients with the duration of the disease 2 years or less at baseline had more pronounced decrease of Abeta42 concentrations compared to those with the duration of the disease more than 2 years at baseline (P<0.05). CSF tau protein concentrations increased in 9/17 but decreased in 8/17 patients. These results suggest that Abeta42 and Abeta40 may be useful in monitoring the long-term progression of AD particularly in the early stages of the disease.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Fragmentos de Peptídeos/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano , Idoso , Biomarcadores/líquido cefalorraquidiano , Progressão da Doença , Seguimentos , Humanos , Fatores de Tempo
10.
Neuroscience ; 92(2): 515-32, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10408601

RESUMO

The entorhinal cortex, which is involved in neural systems related to memory, is selectively degenerated in early Alzheimer's disease. Here, we examined neuropathological changes in the eight entorhinal subfields in post mortem Alzheimer's disease subjects using Thionin and Bielschowsky stains and parvalbumin, calretinin and calbindin-D28k immunohistochemistry. Both histological stains revealed the most dramatic cell loss and neurofibrillary tangle formation to be in layers II and V of the lateral, intermediate and caudal subfields. In accordance, immunohistochemical staining showed that neurons and fibres that contain calcium-binding proteins were also more frequently altered in these subfields than in the rostromedial subfields. Detailed analysis further revealed that non-principal cells containing parvalbumin or calbindin-D28k showed morphological alterations early in the entorhinal pathology of Alzheimer's disease, whereas non-principal neurons containing calretinin were better preserved even in Alzheimer's disease patients with severe entorhinal pathology. The degeneration of parvalbumin-immunoreactive neurons and basket-like networks and calbindin-positive non-principal neurons was observed mainly in layer II, where the calretinin-positive non-principal neurons formed aggregates especially at late stages of the disease. The pyramidal-shaped neurons containing either calretinin or calbindin-D28k were often preserved, although morphological alterations were observed. Our findings indicate that specific subfields of the entorhinal cortex involving neurons that contain distinct calcium-binding proteins are differentially vulnerable in Alzheimer's disease. This could have an impact on the topographically organized inputs and outputs of the entorhinal cortex in Alzheimer's patients.


Assuntos
Doença de Alzheimer/patologia , Córtex Entorrinal/química , Córtex Entorrinal/patologia , Neurônios/química , Parvalbuminas/análise , Proteína G de Ligação ao Cálcio S100/análise , Idoso , Idoso de 80 Anos ou mais , Calbindina 1 , Calbindina 2 , Calbindinas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Degeneração Neural , Fibras Nervosas/química , Neurópilo/química
11.
Eur J Neurosci ; 11(5): 1754-64, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10215928

RESUMO

The highly polysialylated neural cell adhesion molecule (PSA-NCAM) is one of the most promising molecules that contributes to plasticity in the central nervous system. We evaluated PSA-NCAM immunoreactivity in the hippocampal formation of Alzheimer's disease (AD) patients. We found significant increases over control levels in the optical density ratios of PSA-NCAM immunoreactivity in the outer molecular layer/granule cell layer (ODoml/grl) and in the inner molecular layer/granule cell layer (ODiml/grl) in the dentate gyrus of AD patients. The optical density of the granule cell layer in the dentate gyrus did not differ significantly between AD patients and control subjects. However, the number of PSA-NCAM-immunopositive infragranule cells was higher in the AD group compared with control subjects. The major finding in the CA1, subiculum and entorhinal cortex of AD patients was the disorganization of PSA-NCAM-immunoreactive fibres. These results indicate that neuronal remodelling occurs, especially in the dentate gyrus of patients with AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Giro Denteado/fisiologia , Ácido N-Acetilneuramínico/análise , Moléculas de Adesão de Célula Nervosa/análise , Plasticidade Neuronal/fisiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Especificidade de Anticorpos , Western Blotting , Giro Denteado/química , Giro Denteado/citologia , Córtex Entorrinal/química , Córtex Entorrinal/citologia , Córtex Entorrinal/fisiologia , Feminino , Humanos , Masculino , Microscopia Eletrônica , Ácido N-Acetilneuramínico/imunologia , Ácido N-Acetilneuramínico/metabolismo , Moléculas de Adesão de Célula Nervosa/imunologia , Moléculas de Adesão de Célula Nervosa/metabolismo , Neurônios/química , Neurônios/metabolismo , Neurônios/ultraestrutura
12.
Ann Neurol ; 44(6): 923-34, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9851437

RESUMO

Neuronal loss and axonal sprouting are the most typical histopathological findings in the hippocampus of patients with drug-refractory temporal lobe epilepsy (TLE). It is under dispute, however, whether remodeling of neuronal circuits is a continuous process or whether it occurs only during epileptogenesis. Also, little is known about the plasticity outside of the hippocampus. We investigated the immunoreactivity of the highly polysialylated neural cell adhesion molecule (PSA-NCAM) in the surgically removed hippocampus and the entorhinal cortex of patients with drug-refractory TLE (n=25) and autopsy controls (n=7). Previous studies have shown that the expression of PSA-NCAM is associated with the induction of synaptic plasticity, neurite outgrowth, neuronal migration, and events requiring remodeling or repair of tissue. In patients with TLE, the optical density (OD) of punctate PSA-NCAM immunoreactivity was increased both in the inner and outer molecular layers of the dentate gyrus, compared with controls. The intensity of PSA-NCAM immunoreactivity in the inner molecular layer correlated with the duration of epilepsy, severity of hippocampal neuronal loss, density of mossy fiber sprouting, and astrogliosis. In TLE patients with only mild neuronal loss in the hippocampus, the density of infragranular immunopositive neurons was increased twofold compared with controls, whereas in TLE patients with severe neuronal loss, the infragranular PSA-NCAM-positive cells were not present. In the hilus, the somata and tortuous dendrites of some surviving neurons were intensely stained in TLE. PSA-NCAM immunoreactivity was also increased in CA1 and in layer II of the rostral entorhinal cortex, where immunopositive neurons were surrounded by PSA-NCAM-positive fibers and puncta. Our data provide evidence that synaptic reorganization is an active process in human drug-refractory TLE. Moreover, remodeling is not limited to the dentate gyrus, but also occurs in the CA1 subfield and the entorhinal cortex.


Assuntos
Epilepsia do Lobo Temporal/fisiopatologia , Molécula L1 de Adesão de Célula Nervosa , Plasticidade Neuronal/fisiologia , Adulto , Idoso , Cadáver , Giro Denteado/metabolismo , Córtex Entorrinal/metabolismo , Epilepsia do Lobo Temporal/metabolismo , Feminino , Hipocampo/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Moléculas de Adesão de Célula Nervosa/metabolismo , Vias Neurais/fisiopatologia , Valores de Referência , Ácidos Siálicos/metabolismo
13.
J Comp Neurol ; 388(1): 64-88, 1997 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-9364239

RESUMO

Parvalbumin, calretinin, and calbindin-D28k are calcium-binding proteins that are located in largely nonoverlapping neuronal populations in the brain. The authors studied the distribution of parvalbumin-, calretinin-, and calbindin-D28k-immunoreactive (ir) cells, fibers, terminals, and neuropil in the eight subfields of the human entorhinal cortex. The distribution of each of the three calcium-binding proteins largely followed the cytoarchitectonic borders of the eight entorhinal subfields, although the regional and laminar distributions of the three proteins were segregated rather than overlapping. The highest density of parvalbumin-ir neurons and terminals was found in the caudal and lateral subfields of the entorhinal cortex. Calretinin and calbindin-D28k immunoreactivities were high rostromedially, although a large number of calretinin and calbindin-D28k neurons were also found in the caudal subfields. All parvalbumin-ir cells had a morphological appearance of nonpyramidal neurons. Parvalbumin-ir terminals formed basket-like formations around unstained somata and cartridges, suggesting that parvalbumin neurons compose a subpopulation of gamma-aminobutyric acid (GABA)ergic basket cells and chandelier cells, respectively. Although calretinin and calbindin-D28k were also found in numerous nonpyramidal neurons, both were also located in pyramidal-shaped neurons in layers V and VI (calretinin) and in layers II and III (calbindin) of the entorhinal cortex, suggesting that they play roles in projection neurons as well. Moreover, the high density of nonpyramidal neurons containing calcium-binding proteins in layers II and III of the entorhinal cortex suggests that they form an integral component of a network that controls the entorhinal outputs to the hippocampus. Furthermore, the largely nonoverlapping distributions of the parvalbumin-, calretinin-, and calbindin-ir neuronal populations in the entorhinal cortex indicate that each of them may modulate a different subset of topographically organized entorhinal outputs.


Assuntos
Córtex Entorrinal/citologia , Fibras Nervosas/ultraestrutura , Neurônios/citologia , Parvalbuminas/análise , Proteína G de Ligação ao Cálcio S100/análise , Adulto , Idoso , Calbindina 1 , Calbindina 2 , Calbindinas , Simulação por Computador , Dendritos/ultraestrutura , Córtex Entorrinal/anatomia & histologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
14.
Gene ; 175(1-2): 49-57, 1996 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-8917075

RESUMO

Transcription of genes from phage LL-H can be divided into an early phase and a late phase. The early gene region was located in a 5.9-kb segment of the phage LL-H genome and it was part of the sequence that completed the phage LL-H genome sequence, 34 659 bp in size. Phage LL-H is the first completely sequenced Lactobacillus phage. In the main coding strand of phage LL-H genome 48 putative ORFs could be detected, but only four small putative ORFs could be found in the opposite strand. The ORFs covered 85.6% of the main coding strand. Function could be assigned to eleven of the phage LL-H ORFs either by biochemical analyses or by database homologies. A single-strand-binding protein, SSB, was detected in addition to the previously determined functions (small and large subunits of terminase, intron-encoded endonuclease, six structural proteins, phage lysin). For 15 additional ORFs of phage LL-H homology was detected in databases, but no function could be inferred for them.


Assuntos
Bacteriófagos/genética , Genes Precoces/genética , Genes Virais/genética , Genoma Viral , Lactobacillus/virologia , Fases de Leitura Aberta/genética , Bacteriófagos/patogenicidade , Sequência de Bases , Dados de Sequência Molecular , Virulência/genética
15.
Appl Environ Microbiol ; 62(5): 1847-51, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8633887

RESUMO

The phage attachment site, attP, and the integrase-encoding gene, int, are sufficient to promote site-specific integration of the temperate phage mv4 genome into the chromosome of the Lactobacillus delbrueckii host (L. Dupont, B. Boizet-Bonhoure, M. Coddeville, F. Auvray, and P. Ritzenthaler, J. Bacteriol. 177:586--595, 1995). The mv4 genome region containing these elements was compared at the nucleotide and amino acid levels with that of the closely related virulent phage LL-H. Complex DNA rearrangements were identified; a truncated integrase gene and two sites homologous to the mv4 attP site were detected in the genome of the virulent phage LL-H. These observations suggest that the two phages derive from a common temperate ancestor.


Assuntos
Bacteriófagos/genética , Genoma Viral , Lactobacillus/genética , Sequência de Aminoácidos , Sequência de Bases , Lactobacillus/virologia , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência
16.
Microbiology (Reading) ; 141 ( Pt 9): 2183-90, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7496530

RESUMO

An 837 nt long group IA intron was discovered in the Lactobacillus delbrueckii subsp. lactis virulent phage LL-H genome. The LL-H intron conforms well to the secondary structure that is common to all group I introns. The only exception is that the extreme 3' nucleotide of the intron is an A residue instead of the usual G; despite this the intron is efficiently spliced in vivo. This LL-H intron contains an ORF, ORF168, which shows homology with endonucleases encoded by ORFs contained in Bacillus subtilis phage introns. At present, the LL-H intron is the only one found in the phages of lactic acid bacteria and the first one to be found in a phage belonging to the most abundant taxonomic group, group B or Siphoviridae. The LL-H intron interrupts gene terL, the product of which (50.5 kDa, TerL) is significantly homologous to the large subunit of B. subtilis phage SPP1 terminase. The product of the upstream gene, terS of LL-H (15.9 kDa, TerS), shows homology to small subunits of B. subtilis phage terminases.


Assuntos
Bacteriófagos/genética , Endodesoxirribonucleases/genética , Genes Virais , Íntrons/genética , Lactobacillus/virologia , Proteínas Virais/genética , Proteínas Estruturais Virais/genética , Sequência de Aminoácidos , Bacillus subtilis/genética , Sequência de Bases , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Splicing de RNA , RNA Mensageiro/genética , RNA Viral/genética , Alinhamento de Sequência
17.
Gene ; 151(1-2): 53-9, 1994 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-7828907

RESUMO

Two regions from the genome of the virulent Lactobacillus delbrueckii subsp. lactic bacteriophage LL-H were sequenced (2330 and 12939 bp; 44% of the 34.6-kb genome). Together with the previously sequenced region containing the major capsid protein-encoding gene (2498 bp), the sequence had 21 open reading frames (ORFs) on the main coding strand. Only two putative ORFs were detected on the complementary strand. The ORFs covered 93.2% of the sequence. All but four of the ORFs were preceded by a ribosome-binding site. Only four longer non-coding stretches of sequences (175-278 nucleotides (nt) in size) were present. The longest of the non-coding regions contained an A + T-rich sequence that is surrounded by eight perfect copies of an 8-nt sequence that is present both as direct and inverted repeats. This region could represent the origin of replication. All the previously mapped structural protein-encoding genes of phage LL-H were included in the sequence. Genes were identified for the following five proteins: gp19 (encoded by gene g17), gp58 (g71), gp61 (g57), gp75 (g70) and gp89 (g88). N-terminal amino-acid sequencing was performed on gp19 and gp75, and it was found that the N-terminal Met had been post-translationally removed from both proteins.


Assuntos
Bacteriófagos/genética , Genoma Viral , Lactobacillus/virologia , Fases de Leitura Aberta , Proteínas Estruturais Virais/genética , Bacteriófagos/metabolismo , Sequência de Bases , Expressão Gênica , Dados de Sequência Molecular , Sequências Repetitivas de Ácido Nucleico , Origem de Replicação , Mapeamento por Restrição , Proteínas Estruturais Virais/biossíntese
18.
FEMS Microbiol Lett ; 116(3): 315-20, 1994 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-7514146

RESUMO

The putative ribosome binding sites preceding 32 of Lactobacillus delbrueckii subsp. lactis bacteriophage LL-H genes were compared. A highly conserved consensus sequence for the ribosome binding sites of LL-H genes was inferred, GAAAGGAG. This study included the characterization of the last nucleotides of the 3'-end of the 16S rRNA molecule from L. delbrueckii subsp. lactis and its comparison to the ribosome binding site consensus sequence.


Assuntos
Bacteriófagos/genética , Bacteriófagos/metabolismo , Lactobacillus/genética , Lactobacillus/metabolismo , Ribossomos/metabolismo , Sequência de Bases , Sítios de Ligação/genética , Sequência Consenso , DNA Bacteriano/genética , DNA Viral/genética , Genes Virais , Dados de Sequência Molecular , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , RNA Viral/genética , Homologia de Sequência do Ácido Nucleico
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