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1.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 2187-90, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17945698

RESUMO

This paper describes a driver fatigue detection system using an artificial neural network (ANN). Using electroencephalogram (EEG) data sampled from 20 professional truck drivers and 35 non professional drivers, the time domain data are processed into alpha, beta, delta and theta bands and then presented to the neural network to detect the onset of driver fatigue. The neural network uses a training optimization technique called the magnified gradient function (MGF). This technique reduces the time required for training by modifying the standard back propagation (SBP) algorithm. The MGF is shown to classify professional driver fatigue with 81.49% accuracy (80.53% sensitivity, 82.44% specificity) and non-professional driver fatigue with 83.06% accuracy (84.04% sensitivity and 82.08% specificity).


Assuntos
Algoritmos , Condução de Veículo , Diagnóstico por Computador/métodos , Eletroencefalografia/métodos , Fadiga Mental/diagnóstico , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/métodos , Adulto , Feminino , Humanos , Masculino , Fadiga Mental/fisiopatologia , Análise e Desempenho de Tarefas
2.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 2063-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17282633

RESUMO

This paper presents a hands-free head-movement gesture classification system using a Neural Network employing the Magnified Gradient Function (MGF) algorithm. The MGF increases the rate of convergence by magnifying the first order derivative of the activation function, whilst guaranteeing convergence. The MGF is tested on able-bodied and disabled users to measure its accuracy and performance. It is shown that for able-bodied users, a classification improvement from 98.25% to 99.85% is made, and 92.08% to 97.50% for disabled users.

3.
Clin Genet ; 67(1): 93-7, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15617554

RESUMO

Split-hand/split-foot malformation (SHFM) is a genetically heterogeneous disorder, with five known loci, that causes a lack of median digital rays, syndactyly, and aplasia or hypoplasia of the phalanges, metacarpals, and metatarsals. In the only known SHFM2 family, affected males and homozygous females exhibit monodactyly or bidactyly of the hands and lobster-claw feet. This family (1) was revisited to include additional subjects and genealogical data. All 39 affected males and three females fully expressed the SHFM, while 13 carrier females examined exhibited partial expression of SHFM. We narrowed the previously linked 22-Mb genetic interval on Xq24-q26 (2), by analyzing additional family members and typing additional markers. The results define a 5.1-Mb region with a new centromeric boundary at DXS1114 and a telomeric boundary at DXS1192. We did not identify mutations in the exons and exon/intron boundaries of 19 candidate genes. These data suggest that the mutation may lie in a regulatory region of one of these candidate genes or in another gene within the SHFM2 region with unclear role in limb development.


Assuntos
Mapeamento Cromossômico , Cromossomos Humanos X/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Anormalidades Múltiplas/genética , Sequência de Bases , Mapeamento Cromossômico/métodos , Análise Mutacional de DNA , Saúde da Família , Feminino , Haplótipos , Humanos , Masculino , Linhagem
4.
J Med Genet ; 41(4): 266-9, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15060099

RESUMO

Spondylocarpotarsal synostosis syndrome is a rare autosomal recessive disorder characterised by vertebral fusions, frequently manifesting as an unsegmented vertebral bar, as well as fusions of the carpal and tarsal bones. In a study of three consanguineous families and one non-consanguineous family, linkage analysis was used to establish the chromosomal location of the disease gene. Linkage analysis localised the disease gene to chromosome 3p14. A maximum lod score of 6.49 (q = 0) was obtained for the marker at locus D3S3532 on chromosome 3p. Recombination mapping narrowed the linked region to the 5.7 cM genetic interval between the markers at loci D3S3724 and D3S1300. A common region of homozygosity was found between the markers at loci D3S3724 and D3S1300, defining a physical interval of approximately 4 million base pairs likely to contain the disease gene. Identification of the gene responsible for this disorder will provide insight into the genes that play a role in the formation of the vertebral column and joints.


Assuntos
Ossos do Carpo/anormalidades , Cromossomos Humanos Par 3 , Coluna Vertebral/anormalidades , Sinostose/genética , Ossos do Tarso/anormalidades , Ossos do Carpo/diagnóstico por imagem , Mapeamento Cromossômico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Linhagem , Radiografia , Coluna Vertebral/diagnóstico por imagem , Síndrome , Sinostose/diagnóstico , Sinostose/diagnóstico por imagem , Ossos do Tarso/diagnóstico por imagem
5.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 4892-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-17271409

RESUMO

Mobility has become very important for our quality of life. A loss of mobility due to an injury is usually accompanied by a loss of self-confidence. For many individuals, independent mobility is an important aspect of self-esteem. Head movement is a natural form of pointing and can be used to directly replace the joystick whilst still allowing for similar control. Through the use of embedded LINUX and artificial intelligence, a hands-free head movement wheelchair controller has been designed and implemented successfully. This system provides for severely disabled users an effective power wheelchair control method with improved posture, ease of use and attractiveness.

6.
Br Poult Sci ; 44(3): 498-504, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12964635

RESUMO

1. Commercial reproduction of turkeys relies on pooling of semen from multiple males for inseminations. Understanding how sperm characteristics influence paternity under commercial breeding conditions is important to improving production efficiency. 2. The objective of this study was to evaluate progeny production of individual toms following commercial practices of pooling semen to determine if sperm mobility influences progeny production in field conditions. 3. A total of 104 toms were evaluated for sperm mobility. A subset of 10 toms were housed together and semen was collected, pooled and used to inseminate hens (n = 28). Hens were inseminated at 30 weeks of age and weekly thereafter. 4. Ejaculates from each tom were evaluated on two separate days for sperm mobility. Semen from each tom was diluted and layered upon 6% (wt/vol) Accudenz solution. The sperm suspension was incubated at 41 degrees C for 5 min and absorbance was measured with a spectrophotometer. 5. Toms were ranked by absorbance and categorised as high or low if mobility score was +/- 1 SD from the flock mean (average). 6. For parentage determination, DNA was extracted from tom, hen and poult blood. Poult parentage (n = 276) was determined at one day of age or at 14 weeks by analysis of marker genotypes that were generated by polymerase chain reaction (PCR) amplification of genomic DNA with selected microsatellite markers. 7. Sperm mobility differed across males with absorbance values ranging from 0.147 to 0.366. 8. Findings demonstrate differences in poult production among individual toms when semen from multiple males was pooled and inseminated. Toms classified as high, average and low produced 55, 41 and 4% of the offspring, respectively. 9. It appears that sperm mobility is a trait that influences sperm competition among toms under field conditions where sperm numbers inseminated from individual toms are not controlled or constant and that toms with low sperm mobility produce few offspring.


Assuntos
Fertilização/fisiologia , Motilidade dos Espermatozoides/fisiologia , Interações Espermatozoide-Óvulo/fisiologia , Perus/fisiologia , Animais , Cruzamento/métodos , Feminino , Genótipo , Inseminação Artificial/veterinária , Masculino , Repetições de Microssatélites , Reação em Cadeia da Polimerase/veterinária , Espectrofotometria/veterinária
7.
Reproduction ; 123(1): 79-86, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11869189

RESUMO

In avian species, spermatozoa reside in the oviduct for prolonged periods in specialized structures known as sperm storage tubules, but little is known about the relative distribution of spermatozoa in these tubules after successive inseminations by different males. The staining efficacies of various fluorescent dyes for fowl and turkey spermatozoa were evaluated to investigate one proposed mechanism of sperm competition. Hens were then inseminated at different intervals with stained and unstained spermatozoa to observe the spatial distribution of spermatozoa within the storage tubules. Several novel fluorescent lipophilic tracers that successfully stain mammalian spermatozoa either did not stain fowl or turkey spermatozoa, or greatly impaired sperm motility. In contrast, Hoechst 33342 readily stained sperm nuclei (fowl: 25 nmol l-1; turkey: 77 nmol l-1) within 4 h without inhibiting sperm motility, or affecting fertility or the hatching ability of the eggs. Hens were tandemly inseminated with equal numbers of stained or unstained spermatozoa at 24 h intervals and were killed 24 h after the final insemination to study sperm entry and storage within the tubules. Oviductal mucosa containing sperm storage tubules was removed, and individual tubules were classified as containing stained spermatozoa, unstained spermatozoa, a mixture of stained and unstained spermatozoa, or as not containing spermatozoa. Results from the present study indicate that spermatozoa from two different inseminations generally segregate into different storage tubules in both fowl and turkey hens. Storage tubules containing mixed populations of spermatozoa were found in only 4% of fowl and 12% of turkey storage tubules examined. Thus, the mechanism of last-male precedence does not appear to be due to the stratification of spermatozoa within the tubules.


Assuntos
Aves/fisiologia , Oviductos , Espermatozoides/fisiologia , Animais , Galinhas , Feminino , Inseminação Artificial/veterinária , Masculino , Microscopia de Fluorescência , Motilidade dos Espermatozoides , Perus
8.
Gene ; 279(2): 213-9, 2001 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-11733146

RESUMO

We report the isolation, genomic structure, chromosomal location, and expression pattern of the FEM1A gene, the human ortholog of the Caenorhabditis elegans fem-1 and mouse Fem1a genes. The coding sequence is 1851 bp and encodes a 617 amino acid protein. The human FEM1A protein has 65% identity with the mouse Fem1a protein and 34% identity with the C. elegans fem-1 protein, indicating conservation of this protein. The N-terminal region of the encoded protein contains six ankyrin repeat elements, a motif found in signaling and transcriptional regulatory molecules such as Notch and glp1. The gene was highly expressed in human kidney and cardiac tissue, and was expressed at lower levels in multiple tissues, including cartilage. FEM1A was localized to chromosome 5q23.1, a region of conserved synteny with a portion of mouse chromosome 17 that contains Fem1a. In C. elegans, fem-1 is involved in a pathway necessary for sex determination. The identification of a human homolog of this conserved gene suggests a potential role for this sex-determining molecule in humans.


Assuntos
Proteínas de Caenorhabditis elegans , Proteínas de Ciclo Celular/genética , Sequência de Aminoácidos , Animais , Northern Blotting , Caenorhabditis elegans/genética , Mapeamento Cromossômico , Cromossomos Humanos Par 5/genética , DNA Complementar/química , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Éxons , Feminino , Expressão Gênica , Genes/genética , Humanos , Íntrons , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Mapeamento de Híbridos Radioativos , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Distribuição Tecidual
9.
J Pharmacol Exp Ther ; 299(2): 468-76, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11602656

RESUMO

Cyclooxygenases (COX)-1 and -2 are the key enzymes in the conversion of arachidonic acid to prostaglandins. COX-2 appears to play an emerging role in inflammation and carcinogenesis. Nonsteroidal anti-inflammatory drugs (NSAIDs) are used for the treatment of numerous diseases and reduce the risk of developing colorectal cancer. Polymorphisms in the COX-2 gene could alter enzyme expression, function, and/or the response to NSAIDs. Therefore, they could modify individual risks for developing cancer and other diseases or the occurrence of side effects or sensitivity toward selective or nonselective COX inhibitors. We sequenced the COX-2 gene of 72 individuals and identified rare polymorphisms in the promoter and the coding region. A COX-2 molecular model was used to locate the coding region polymorphisms relative to functional sites in the protein, and the COX-2 V511A polymorphism was very near to the active site. This variant protein was expressed, and function was evaluated, but no difference was detected in metabolism of the COX-2 substrates, arachidonic acid, linoleic acid, and 2-arachidonyl glycerol, compared with the wild type. The Km values for arachidonic acid showed no differences between the COX-2 wild type and V511A mutant. Inhibition with selective or nonselective COX inhibitors was essentially the same for the two enzymes. The absence of functionally important polymorphisms in the COX-2 gene may suggest that there has been selective pressure against those single nucleotide polymorphisms because of the critical role of this enzyme in maintenance of homeostasis.


Assuntos
Isoenzimas/genética , Prostaglandina-Endoperóxido Sintases/genética , Anti-Inflamatórios não Esteroides/farmacologia , Povo Asiático , População Negra , Western Blotting , Linhagem Celular , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Clonagem Molecular , Ciclo-Oxigenase 2 , DNA/análise , DNA/genética , Humanos , Isomerismo , Proteínas de Membrana , Modelos Moleculares , Mutagênese Sítio-Dirigida , Polimorfismo Genético , Prostaglandinas/biossíntese , População Branca
10.
Am J Physiol Heart Circ Physiol ; 280(3): H1173-81, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11179061

RESUMO

To determine whether the effects of fatty acids on the diabetic heart during ischemia involve altered glycolytic ATP and proton production, we measured energetics and intracellular pH (pH(i)) by using (31)P NMR spectroscopy plus [2-(3)H]glucose uptake in isolated rat hearts. Hearts from 7-wk streptozotocin diabetic and control rats, perfused with buffer containing 11 mM glucose, with or without 1.2 mM palmitate or the ketone bodies, 4 mM beta-hydroxybutyrate plus 1 mM acetoacetate, were subjected to 32 min of low-flow (0.3 ml x g wet wt(-1) x min(-1)) ischemia, followed by 32 min of reperfusion. In control rat hearts, neither palmitate nor ketone bodies altered the recovery of contractile function. Diabetic rat hearts perfused with glucose alone or with ketone bodies, had functional recoveries 50% lower than those of the control hearts, but palmitate restored recovery to control levels. In a parallel group with the functional recoveries, palmitate prevented the 54% faster loss of ATP in the diabetic, glucose-perfused rat hearts during ischemia, but had no effect on the rate of ATP depletion in control hearts. Palmitate decreased total glucose uptake in control rat hearts during low-flow ischemia, from 106 +/- 17 to 52 +/- 12 micromol/g wet wt, but did not alter the total glucose uptake in the diabetic rat hearts, which was 42 +/- 5 micromol/g wet wt. Recovery of contractile function was unrelated to pH(i) during ischemia; the glucose-perfused control and palmitate-perfused diabetic hearts had end-ischemic pH(i) values that were significantly different at 6.36 +/- 0.04 and 6.60 +/- 0.02, respectively, but had similar functional recoveries, whereas the glucose-perfused diabetic hearts had significantly lower functional recoveries, but their pH(i) was 6.49 +/- 0.04. We conclude that fatty acids, but not ketone bodies, protect the diabetic heart by decreasing ATP depletion, with neither having detrimental effects on the normal rat heart during low-flow ischemia.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Ácidos Graxos não Esterificados/farmacologia , Corpos Cetônicos/farmacologia , Isquemia Miocárdica/metabolismo , Animais , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/fisiologia , Glucose/farmacocinética , Hipoglicemiantes/farmacologia , Técnicas In Vitro , Insulina/farmacologia , Espectroscopia de Ressonância Magnética , Masculino , Contração Miocárdica/efeitos dos fármacos , Contração Miocárdica/fisiologia , Palmitatos/farmacologia , Isótopos de Fósforo , Ratos , Ratos Wistar
11.
Genomics ; 71(2): 163-73, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11161810

RESUMO

We characterize the cDNA and genomic structure of NSBP1, and demonstrate that it is a nuclear protein and the homologue of mouse Nsbp1, which is known to encode a nucleosomal binding and transcriptional activating protein related to the HMG-14/-17 chromosomal proteins. The encoded NSBP1 protein has 86% amino acid similarity to Nsbp1, including identity in nucleosomal binding domains of the HMG-14/-17 proteins. Our radiation hybrid data localize NSBP1 and Nsbp1 to homologous regions of chromosome X, with NSBP1 in Xq13.3 between DXS983 and DXS995 and Nsbp1 in the interval DXMit65 and DXMit39. Although Nsbp1 produces one mRNA transcript, NSBP1 produces three transcripts with alternate polyadenylated sites. The 3' untranslated region (UTR) of NSPB1 mRNA also contains several AU-rich elements (AREs), which are associated with rapid mRNA turnover. Northern analysis of NSBP1/Nsbp1 shows differences in transcript abundance among adult and fetal tissues, with predominant expression in liver, kidney, trabecular bone, and bone marrow stromal cells. However, a reverse transcriptase-PCR analysis shows nearly ubiquitous expression of the three NSBP1 transcripts in all tissues examined, although the abundance of each transcript was not quantified. NSBP1 is encoded by six exons and has exon-intron boundaries identical to the HMG-14/-17 genes. The last exon and the 3' UTR of NSBP1 contain retrotransposon sequences of HAL1, HERV-H, and L1MB7, suggesting that these retrotransposons were involved in the origin of NSPB1 from an ancestral-like HMG-14/-17 gene. The similarities among NSBP1, Nsbp1, and the HMG-14/-17 proteins suggest that NSBP1 may function as a nucleosomal binding and transcriptional activating element. Further, the AREs in the 3' UTR of NSPB1 suggest that alternate poly(A) site selection may mediate the mRNA stability of this gene.


Assuntos
Proteínas de Transporte/genética , Genes/genética , Proteínas HMGN , Transativadores/genética , Regiões 3' não Traduzidas , Animais , Sequência de Bases , Mapeamento Cromossômico , Proteínas de Grupo de Alta Mobilidade/genética , Humanos , Sequências Repetitivas Dispersas , Camundongos , Dados de Sequência Molecular , Nucleossomos/genética , Sítios de Splice de RNA , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Distribuição Tecidual , Transcrição Gênica/genética , Cromossomo X/genética
12.
Protein Expr Purif ; 20(2): 252-64, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11049749

RESUMO

We investigated the ability of signal peptides of eukaryotic origin (human, mouse, and yeast) to efficiently direct model proteins to the Escherichia coli periplasm. These were compared against a well-characterized prokaryotic signal peptide-OmpA. Surprisingly, eukaryotic signal peptides can work very efficiently in E. coli, but require optimization of codon usage by codon-based mutagenesis of the signal peptide coding region. Analysis of the 5' of periplasmic and cytoplasmic E. coli genes shows some codon usage differences.


Assuntos
Códon/genética , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Periplasma/metabolismo , Sinais Direcionadores de Proteínas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Bases de Dados Factuais , Escherichia coli/metabolismo , Genes Bacterianos/genética , Código Genético , Humanos , Fragmentos Fab das Imunoglobulinas/genética , Camundongos , Dados de Sequência Molecular , Mutagênese/genética , Conformação de Ácido Nucleico , Plasmídeos/genética , Transporte Proteico , Estabilidade de RNA , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de Proteína , Leveduras/genética
13.
J Androl ; 21(5): 656-63, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10975412

RESUMO

Recently, we showed that murine strain differences to the testicular toxicity of cadmium (Cd) are the result of variable transport of Cd across the blood-testis barrier. Because Cd is a nonessential trace element, it must be using the transporter for an endogenous substance. The objectives for this study were to determine the natural ligand for the transport system used by Cd to enter testis and brain, and to determine whether the transport of that natural ligand also differs among Cd-sensitive and -resistant murine strains. Because zinc (Zn) and Cd are cations of similar size and charge, and because Cd has been shown to inhibit Zn uptake in a variety of systems, we hypothesized that Cd was using Zn transporters to enter tissues. In this study we characterized Zn transport into the testis and brain of Cd-sensitive and -resistant murine strains. We found that the transport of 65Zn into testis and brain of Cd-resistant A/J mice was significantly reduced compared with that in Cd-sensitive 129/J mice. In 129/J mice, unlabeled CdCl2 significantly reduced 65Zn transport by 56% in testes and by 47% in brain. Pretreatment with Zn had no significant effect on 109Cd transport rates into testes or brain of 129/J or A/J mice, but did reduce the percentage of the injected 109Cd dose in testes of 129/J mice by 44% within 60 minutes. From these results we can conclude that Cd is using transport systems that normally function to regulate Zn levels in testes and brain. Murine strain resistance to the testicular effects of Cd is associated with a concomitant attenuation of the Zn transport system in testis.


Assuntos
Encéfalo/metabolismo , Cádmio/farmacologia , Camundongos Endogâmicos/metabolismo , Testículo/metabolismo , Zinco/farmacocinética , Animais , Transporte Biológico/efeitos dos fármacos , Cádmio/farmacocinética , Resistência a Medicamentos , Masculino , Camundongos , Especificidade da Espécie , Fatores de Tempo
14.
Protein Eng ; 13(3): 201-6, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10775662

RESUMO

The peptide sequence (N)DKTH(C) was previously investigated as a site for efficient, specific cleavage of a fusion protein by cupric ions using a humanized gamma1 Fab' as a model protein. Here we show that conservative mutations to three of the residues in the introduced cleavage site resulted in cleavage sites that were significantly improved. They were cleaved more efficiently by Cu(2+), such that cleavage reactions could be shorter, of lower pH or at a lower temperature. Some were even found to be measurably cleaved by Ni(2+). Use of these new cleavage sequences along with cupric ions may provide a more rapid and less harsh method for cost-effective, large-scale proteolytic cleavage of fusion proteins and peptides.


Assuntos
Cobre/farmacologia , Fragmentos Fab das Imunoglobulinas/química , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Sequência Conservada , Humanos , Concentração de Íons de Hidrogênio , Fragmentos Fab das Imunoglobulinas/metabolismo , Cinética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Níquel/farmacologia , Oligodesoxirribonucleotídeos , Plasmídeos , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Termodinâmica
15.
J Med Genet ; 37(4): 263-71, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10745044

RESUMO

Achondrogenesis II-hypochondrogenesis and severe spondyloepiphyseal dysplasia congenita (SEDC) are lethal forms of dwarfism caused by dominant mutations in the type II collagen gene (COL2A1). To identify the underlying defect in seven cases with this group of conditions, we used the combined strategy of cartilage protein analysis and COL2A1 mutation analysis. Overmodified type II collagen and the presence of type I collagen was found in the cartilage matrix of all seven cases. Five patients were heterozygous for a nucleotide change that predicted a glycine substitution in the triple helical domain (G313S, G517V, G571A, G910C, G943S). In all five cases, analysis of cartilage type II collagen suggested incorporation of the abnormal alpha1(II) chain in the extracellular collagen trimers. The G943S mutation has been reported previously in another unrelated patient with a strikingly similar phenotype, illustrating the possible specific effect of the mutation. The radiographically less severely affected patient was heterozygous for a 4 bp deletion in the splice donor site of intron 35, likely to result in aberrant splicing. One case was shown to be heterozygous for a single nucleotide change predicted to result in a T1191N substitution in the carboxy-propeptide of the proalpha1(II) collagen chain. Study of the clinical, radiographic, and morphological features of the seven cases supports evidence for a phenotypic continuum between achondrogenesis II-hypochondrogenesis and lethal SEDC and suggests a relationship between the amount of type I collagen in the cartilage and the severity of the phenotype.


Assuntos
Acondroplasia/genética , Doenças do Colágeno/genética , Colágeno/genética , Análise Mutacional de DNA , Feminino , Genótipo , Humanos , Recém-Nascido , Masculino , Mutação , Fenótipo
16.
J Androl ; 21(1): 65-71, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10670521

RESUMO

Since all domestic turkeys are produced through artificial insemination, a measurable sperm characteristic that would be predictive of fertility would allow for the culling of poor males, resulting in improved reproductive efficiency. The sperm mobility test (SMT), which quantifies sperm penetration into an Accudenz solution, has been shown to correlate highly with fertilization potential of individual turkeys. Since this sire-selection test is based on the differences in sperm mobility between whole ejaculates from individual males, the objective of this study was to determine whether specific sperm velocity parameters would correlate with the SMT and to determine whether these characteristics could account for phenotypic differences in sperm mobility observed between males. The SMT was used to rank males within a flock (n = 110) in triplicate and to classify them into high, average, and low sperm mobility phenotypes on the basis of the sperm mobility index. Several sperm velocity parameters were evaluated for each male by a computer-aided sperm analysis (CASA) system, the Hobson Sperm Tracker. The types of measurements taken of 200 sperm tracks/ejaculate included the following: curvilinear velocity (VCL), average path velocity (VAP), straight-line velocity (VSL), linearity (LIN), beat-cross frequency (BCF), and mean angular displacement (MAD). Significant positive correlations were found between VSL, LIN, BCF, and sperm mobility, and a significant negative correlation was seen between MAD and sperm mobility. Subpopulations of sperm that had penetrated the Accudenz solution were isolated from each mobility phenotype and were analyzed by CASA, and significant correlations were again observed between VSL, LIN, BCF, and sperm mobility. We conclude that sperm velocity and linearity contribute to overall sperm mobility phenotype and are important characteristics of turkey sperm function. Key words: Motility, computer, spermatozoa.


Assuntos
Processamento Eletrônico de Dados , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Perus/fisiologia , Animais , Masculino , Fenótipo , Fatores de Tempo
18.
Poult Sci ; 79(12): 1797-802, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11194043

RESUMO

Our objectives were to evaluate: 1) the efficacy of the Sperm Mobility Test on commercial turkey farms, and 2) the influence of sperm mobility phenotype on fertility when insemination parameters are varied. In research flocks, differences in sperm mobility among toms are predictive of fertility. We wanted to test the efficacy of this sire selection test in practical, real-world situations, evaluating its usefulness in terms of assessing large numbers of toms, different strains of turkeys, and variable management practices. Utilizing field study results, controlled studies were then conducted to improve test parameters. For the field trials, semen from each of 405 breeder toms (11 strains or lines) was evaluated either in duplicate (n = 285) or in triplicate (n = 120). Sperm mobility was normally distributed among all toms tested, except for one strain. Because the sperm mobility indices for toms evaluated in these field trials were higher than those observed in research flocks, the Sperm Mobility Test was modified to increase the separation between high and low sperm mobility phenotypes by increasing the concentration of Accudenz. To determine the effects of sperm mobility and insemination dose on sustained fertility through time, hens from a research flock were inseminated twice before the onset of lay with sperm from toms classified as high-, average-, or low-mobility in concentrations of 25 to 400 million sperm per artificial insemination dose, and egg fertility was evaluated over a 5-wk period. Toms with the high-mobility sperm phenotype maintained higher fertility (P < 0.05) over the 5-wk period at all insemination doses compared with toms with low-mobility sperm. Toms with high-mobility sperm sired equal numbers of poults in a sperm competition study in which numbers favored low-mobility toms by 3:1. These results demonstrate that the Sperm Mobility Test can be used for on-farm evaluation of semen quality of toms in commercial flocks and that sperm mobility influences fertility and sire fitness.


Assuntos
Fertilidade , Inseminação Artificial/veterinária , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Perus/fisiologia , Animais , Feminino , Masculino , Fenótipo
19.
Mamm Genome ; 10(10): 1000-4, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10501970

RESUMO

Mutations in the Caenorhabditis elegans gene clk-1 have a major effect on slowing development and increasing life span. The Saccharomyces cerevisiae homolog COQ7 encodes a mitochondrial protein involved in ubiquinone biosynthesis and, hence, is required for respiration and gluconeogenesis. In this study, RT-PCR and 5' RACE were used to isolate both human and mouse clk-1/COQ7 homologs. Human CLK-1 was mapped to Chr 16(p12-13.1) by Radiation Hybrid (RH) and fluorescence in situ hybridization (FISH) methods. The number and location of human CLK1 introns were determined, and the location of introns II and IV are the same as in C. elegans. Northern blot analysis showed that three different isoforms of CLK-1 mRNA are present in several tissues and that the isoforms differ in the amount of expression. The functional equivalence of human CLK-1 to the yeast COQ7 homolog was tested by introducing either a single or multicopy plasmid containing human CLK-1 cDNA into yeast coq7 deletion strains and assaying for growth on a nonfermentable carbon source. The human CLK-1 gene was able to functionally complement yeast coq7 deletion mutants. The protein similarities and the conservation of function of the CLK-1/clk-1/COQ7 gene products suggest a potential link between the production of ubiquinone and aging.


Assuntos
Envelhecimento/genética , Proteínas de Caenorhabditis elegans , Caenorhabditis elegans/genética , Proteínas de Helminto/genética , Ubiquinona/biossíntese , Processamento Alternativo , Sequência de Aminoácidos , Animais , Relógios Biológicos/genética , Mapeamento Cromossômico , Cromossomos Humanos Par 16 , Clonagem Molecular , Sequência Conservada , Evolução Molecular , Éxons/genética , Teste de Complementação Genética , Humanos , Hibridização in Situ Fluorescente , Íntrons/genética , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos , Ubiquinona/genética , Leveduras
20.
Biol Reprod ; 61(2): 422-7, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10411522

RESUMO

We have devised a novel means of investigating competitive fertilization in turkeys, using microsatellite genotyping to identify male parentage. Our results demonstrate that sperm mobility is a mechanism responsible in part for paternity efficiency in turkeys. Sperm mobility is composed of several parameters in which sperm motility is a component. Differences between ejaculates in the number of sperm penetrating into a dense, insert, nontoxic solution were measured and used to classify males into high, average, or low sperm mobility phenotypes. Microsatellite genotyping was used to determine parentage of poults after equal numbers of sperm from 10 males (either high or average phenotype, n = 5, mixed with low phenotype, n = 5) were inseminated simultaneously. In a separate study, the numbers of sperm hydrolyzing the perivitelline layer of eggs were compared between hens inseminated with sperm from high-, average-, or low-phenotype males. Overall, heterospermic inseminations resulted in consistently fewer offspring produced by low-mobility phenotype males. This correlated with physiological data in which semen from the low-mobility males had reduced numbers of sperm at the fertilization site as determined by sperm hole counts in the perivitelline layer of eggs. This is the first illustration of a measurable sperm trait predictive of paternity success in a competitive fertilization trial in turkeys, a species that is predominately reproduced by artificial insemination of multiple-sire pools.


Assuntos
Fertilização/fisiologia , Motilidade dos Espermatozoides/fisiologia , Perus/fisiologia , Animais , Cruzamento , Ovos , Feminino , Masculino , Fenótipo , Interações Espermatozoide-Óvulo
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