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BACKGROUND: In an exploratory 91-participant phase 2a clinical trial (AscenD-LB, NCT04001517) in dementia with Lewy bodies (DLB), neflamapimod showed improvement over placebo on multiple clinical endpoints. To confirm those results, a phase 2b clinical study (RewinD-LB, NCT05869669 ) that is similar to AscenD-LB has been initiated. OBJECTIVES: To optimize the choice of patient population, primary endpoint, and biomarker evaluations in RewinD-LB. DESIGN: Evaluation of the efficacy results from AscenD-LB, the main results of which, and a re-analysis after stratification for absence or presence of AD co-pathology (assessed by plasma ptau181), have been published. In addition, the MRI data from a prior phase 2a clinical trial in Early Alzheimer's disease (AD), were reviewed. SETTING: 22 clinical sites in the US and 2 in the Netherlands. PARTICIPANTS: Probable DLB by consensus criteria and abnormal dopamine uptake by DaTscan™ (Ioflupane I123 SPECT). INTERVENTION: Neflamapimod 40mg capsules or matching placebo capsules, twice-a-day (BID) or three-times-a-day (TID), for 16 weeks. MEASUREMENTS: 6-test Neuropsychological Test Battery (NTB) assessing attention and executive function, Clinical Dementia Rating Sum-of-Boxes (CDR-SB), Timed Up and Go (TUG), International Shopping List Test (ISLT). RESULTS: Within AscenD-LB, patients without evidence of AD co-pathology exhibited a neflamapimod treatment effect that was greater than that in the overall population and substantial (cohen's d effect size vs. placebo ≥ for CDR-SB, TUG, Attention and ISLT-recognition). In addition, the CDR-SB and TUG performed better than the cognitive tests to demonstrate neflamapimod treatment effect in comparison to placebo. Further, clinical trial simulations indicate with 160-patients (randomized 1:1), RewinD-LB conducted in patients without AD co-pathology has >95% (approaching 100%) statistical power to detect significant improvement over placebo on the CDR-SB. Preliminary evidence of positive treatment effects on beta functional connectivity by EEG and basal forebrain atrophy by MRI were obtained in AscenD-LB and the Early AD study, respectively. CONCLUSION: In addition to use of a single dose regimen of neflamapimod (40mg TID), key distinctions between phase 2b and phase 2a include RewinD-LB (1) excluding patients with AD co-pathology, (2) having CDR-SB as the primary endpoint, and (3) having MRI studies to evaluate effects on basal forebrain atrophy.
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Bencilaminas , Fluorocarburos , Indoles , Enfermedad por Cuerpos de Lewy , Humanos , Enfermedad por Cuerpos de Lewy/tratamiento farmacológico , Enfermedad por Cuerpos de Lewy/diagnóstico por imagen , Anciano , Femenino , Masculino , Método Doble Ciego , Imagen por Resonancia Magnética , Biomarcadores/sangre , Anciano de 80 o más Años , Pruebas NeuropsicológicasRESUMEN
Nitazoxanide (NTZ) is effective against helminths and numerous microorganisms, including bacteria and viruses. In vivo, NTZ is metabolized into Tizoxanide (TIZ), which is the active circulating metabolite. With the emergence of SARS-Cov-2 as a Pandemic agent, NTZ became one of the molecules already approved for human use to engage clinical trials, due to results in vitro showing that NTZ was highly effective against the SARS-Cov-2, agent of COVID-19. There are currently several ongoing clinical trials mainly in the USA and Brazil involving NTZ due not only to the in vitro results, but also for its long-known safety. Here, we study the response of Vero cells to TIZ treatment and unveil possible mechanisms for its antimicrobial effect, using a label-free proteomic approach (LC/MS/MS) analysis to compare the proteomic profile between untreated- and TIZ-treated cells. Fifteen differentially expressed proteins were observed related to various biological processes, including translation, intracellular trafficking, RNA processing and modification, and signal transduction. The broad antimicrobial range of TIZ points towards its overall effect in lowering cell metabolism and RNA processing and modification. The decreased levels of FASN, HNRNPH and HNRNPK with the treatment appear to be important for antiviral activity.
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Antiinfecciosos/farmacología , Proteoma/efectos de los fármacos , Tiazoles/farmacología , Animales , Chlorocebus aethiops , Ácido Graso Sintasas/genética , Ácido Graso Sintasas/metabolismo , Proteoma/genética , Proteoma/metabolismo , Ribonucleoproteínas/genética , Ribonucleoproteínas/metabolismo , Células VeroRESUMEN
Neflamapimod (previously code named VX-745) is a clinical phase 2b-ready highly specific inhibitor of the intra-cellular enzyme p38 mitogen activated protein kinase alpha ("p38α") that is being developed as a disease-modifying drug for Alzheimer's disease (AD) that acts via targeting synaptic dysfunction. Neflamapimod was discovered through a proprietary structure-based drug discovery platform at Vertex Pharmaceuticals, and developed previously by Vertex through to phase 2a in rheumatoid arthritis. EIP Pharma licensed the compound in 2014 for development and commercialization as a treatment of central nervous system (CNS) disorders. Neflamapimod is the most advanced in the clinic drug that targets specific molecular mechanisms within neurons that leads to synaptic dysfunction, the pathogenic process that is now considered to be a major driver of the development of memory deficits and disease progression in the early stages of AD. Based on the scientific rationale of targeting synaptic dysfunction and the preclinical data, neflamapimod has the potential to both reverse memory deficits and slow disease progression. Phase 2a clinical data in patients with early-stage AD (MMSE 20-28, biomarker positive) provides evidence that the preclinical science may be translatable to human Alzheimer's, as 6- to 12-weeks of neflamapimod treatment led to significant improvement in episodic memory, the best clinical measure of synaptic dysfunction in AD. A phase 2b six-month placebo-controlled 150-patient clinical study is anticipated to start by end of 2017. This study is designed to definitively demonstrate that neflamapimod reverses memory deficits, and also to provide preliminary evidence that the drug slows disease progression.
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Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores Enzimáticos/uso terapéutico , Proteína Quinasa 14 Activada por Mitógenos/antagonistas & inhibidores , Nootrópicos/uso terapéutico , Piridazinas/uso terapéutico , Pirimidinas/uso terapéutico , Enfermedad de Alzheimer/enzimología , Progresión de la Enfermedad , Humanos , Memoria Episódica , Sinapsis/efectos de los fármacos , Sinapsis/enzimologíaRESUMEN
The vertebral arteries are commonly affected by anatomical variation. This variation ranges from slight asymmetry in arterial diameter between the right and left sides to complete absence of a vertebral artery on one side. Asymmetry in diameter is a common observation, although complete absence of the artery is rare. Herein, we report on a 79-year-old male anatomical donor who, upon brain removal, was found to have a single intracranial vertebral artery which was the sole source of the basilar artery. During dissection of the neck, both right and left vertebral arteries were identified arising from the subclavian arteries. The vertebral arteries were dissected from the transverse foramina and followed into the skull. The right vertebral artery terminated by supplying the spinal cord, consistent with the distribution of the posterior spinal artery. Such vascular anomalies are clinically significant, as they may lead to abnormal patterns of sensory-motor deficiencies in stroke and are at risk of iatrogenic injury during surgical procedures.
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Aorta Torácica/anomalías , Anomalías Cardiovasculares , Arteria Subclavia/anomalías , Arteria Vertebral/anomalías , Anciano , Humanos , MasculinoAsunto(s)
Encefalitis/diagnóstico , Encefalitis/tratamiento farmacológico , Puente/patología , Esteroides/uso terapéutico , Linfocitos T , Ataxia/etiología , Calcio , Canales de Calcio Tipo Q , Enfermedad Crónica , Encefalitis/patología , Femenino , Humanos , Inflamación/diagnóstico , Inflamación/tratamiento farmacológico , Inflamación/patología , Persona de Mediana Edad , Síndrome , Linfocitos T/patología , Vértigo/etiologíaRESUMEN
Compared to fathead minnow, walleye demonstrate low susceptibility to experimental infection with VHSV IVb, regardless of route of exposure or water temperature at time of infection. In triplicate and duplicate groups, walleye were intraperitoneally (i.p.) injected (102 -108 pfu/fish) or waterborne-exposed (w; 1.4 × 107 pfu mL-1 ) with VHSV IVb. High cumulative mortality (64-100%) and severe gross lesions associated with VHSV IVb infection were evident only in fish i.p. injected with 108 pfu at 12 °C. These fish had multifocal necrosis of several tissues including the gill and heart. There was no difference in mortality between walleye infected (w or i.p.) at 12 °C (spring stocking) compared with a declining temperature profile from 18 to 12 °C (fall stocking). There were significant differences (P < 0.05) in mortality between four extant walleye strains following i.p. infection, indicating that the choice of walleye strain for stocking might be an important consideration. Viral antigen was found in both i.p. and w-exposed walleye using immunohistochemistry, mostly within the gill and skin of w-exposed fish and most prominently in dermal fibrocytes. VHSV IVb was detected in multiple tissues from 6 to 21 days post-infection using reverse transcriptase quantitative polymerase chain reaction (RT-qPCR).
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We present a LIGO search for short-duration gravitational waves (GWs) associated with soft gamma ray repeater (SGR) bursts. This is the first search sensitive to neutron star f modes, usually considered the most efficient GW emitting modes. We find no evidence of GWs associated with any SGR burst in a sample consisting of the 27 Dec. 2004 giant flare from SGR 1806-20 and 190 lesser events from SGR 1806-20 and SGR 1900+14. The unprecedented sensitivity of the detectors allows us to set the most stringent limits on transient GW amplitudes published to date. We find upper limit estimates on the model-dependent isotropic GW emission energies (at a nominal distance of 10 kpc) between 3x10;{45} and 9x10;{52} erg depending on waveform type, detector antenna factors and noise characteristics at the time of the burst. These upper limits are within the theoretically predicted range of some SGR models.
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The Laser Interferometer Gravitational-Wave Observatory has performed a third science run with much improved sensitivities of all three interferometers. We present an analysis of approximately 200 hours of data acquired during this run, used to search for a stochastic background of gravitational radiation. We place upper bounds on the energy density stored as gravitational radiation for three different spectral power laws. For the flat spectrum, our limit of omega0 < 8.4 x 10(-4) in the 69-156 Hz band is approximately 10(5) times lower than the previous result in this frequency range.
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We place direct upper limits on the amplitude of gravitational waves from 28 isolated radio pulsars by a coherent multidetector analysis of the data collected during the second science run of the LIGO interferometric detectors. These are the first direct upper limits for 26 of the 28 pulsars. We use coordinated radio observations for the first time to build radio-guided phase templates for the expected gravitational-wave signals. The unprecedented sensitivity of the detectors allows us to set strain upper limits as low as a few times 10(-24). These strain limits translate into limits on the equatorial ellipticities of the pulsars, which are smaller than 10(-5) for the four closest pulsars.
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Dieting and stress are important in the etiology and maintenance of eating disorders, and dieting strongly predicts stress-induced overeating in humans. We hypothesized that caloric restriction and stress interact in a unique manner to promote binge eating. To test this hypothesis, a group of young female rats were cycled through a restriction period (4 days of 66% of control food intake) followed by 6 days of free feeding prior to being stressed by acute foot shock. After three of these cycles, the food intake of rats exposed only to restriction (R), or only to stress (S), did not differ from controls. However, R+S rats that were restricted and refed, despite normal body weight and food intake after free feeding, engaged in a powerful bout of hyperphagia when stressed (Experiment 1). The R + S effect was replicated in an older group of rats (Experiment 2). The hyperphagia was characteristically binge-like, it constituted a 40% selective increase in highly palatable (HP) food (P < .001) over a discrete period of time (within 24 h post-stress), and reflected feeding for reward (higher HP:chow ratio) over metabolic need as occurred after restriction (higher chow:HP ratio). Subsequent experiments revealed that binge eating did not occur if only chow was available (Experiment 3) or if restriction-refeeding (R-R) did not proximally precede stress (Experiment 4). Experiment 5 revealed that a history of R-R cycles followed by only one stress episode was sufficient to increase intake to 53% above controls as early as 2 h after stress (P < .001). This animal model of binge eating should facilitate investigations into the neurochemical changes induced by dieting and environmental stress to produce disordered eating and provide a preclinical tool to test preventive strategies and treatments more relevant to bulimia nervosa, multiple cases of binge eating disorder (BED) and binge-purge type anorexia nervosa.
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Bulimia/etiología , Bulimia/fisiopatología , Privación de Alimentos/fisiología , Estrés Fisiológico/complicaciones , Animales , Modelos Animales de Enfermedad , Electrochoque , Ingestión de Energía , Femenino , Alimentos , Preferencias Alimentarias , Pie , Ratas , Ratas Sprague-Dawley , GustoRESUMEN
Identification of all the protein components of the large subunit (39 S) of the mammalian mitochondrial ribosome has been achieved by carrying out proteolytic digestions of whole 39 S subunits followed by analysis of the resultant peptides by liquid chromatography and mass spectrometry. Peptide sequence information was used to search the human EST data bases and complete coding sequences were assembled. The human mitochondrial 39 S subunit has 48 distinct proteins. Twenty eight of these are homologs of the Escherichia coli 50 S ribosomal proteins L1, L2, L3, L4, L7/L12, L9, L10, L11, L13, L14, L15, L16, L17, L18, L19, L20, L21, L22, L23, L24, L27, L28, L30, L32, L33, L34, L35, and L36. Almost all of these proteins have homologs in Drosophila melanogaster, Caenorhabditis elegans, and Saccharomyces cerevisiae mitochondrial ribosomes. No mitochondrial homologs to prokaryotic ribosomal proteins L5, L6, L25, L29, and L31 could be found either in the peptides obtained or by analysis of the available data bases. The remaining 20 proteins present in the 39 S subunits are specific to mitochondrial ribosomes. Proteins in this group have no apparent homologs in bacterial, chloroplast, archaebacterial, or cytosolic ribosomes. All but two of the proteins has a clear homolog in D. melanogaster while all can be found in the genome of C. elegans. Ten of the 20 mitochondrial specific 39 S proteins have homologs in S. cerevisiae. Homologs of 2 of these new classes of ribosomal proteins could be identified in the Arabidopsis thaliana genome.
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Mitocondrias Hepáticas/química , Proteínas Ribosómicas/química , Ribosomas/química , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bovinos , Electroforesis en Gel Bidimensional , Espectrometría de Masas , Datos de Secuencia Molecular , Peso Molecular , Conformación de Ácido Nucleico , Mapeo Peptídico , ARN Ribosómico/química , Homología de Secuencia de AminoácidoRESUMEN
Proteins in the small subunit of the mammalian mitochondrial ribosome were separated by two-dimensional polyacrylamide gel electrophoresis. Four individual proteins were subjected to in-gel Endoprotease Lys-C digestion. The sequences of selected proteolytic peptides were obtained by electrospray tandem mass spectrometry. Peptide sequences obtained from in-gel digestion of individual spots were used to screen human, mouse, and rat expressed sequence tag databases, and complete consensus cDNAs for these species were deduced in silico. The corresponding protein sequences were characterized by comparison to known ribosomal proteins in protein databases. Four different classes of mammalian mitochondrial small subunit ribosomal proteins were identified. Only two of these proteins have significant sequence similarities to ribosomal proteins from prokaryotes. These proteins are homologs to Escherichia coli S9 and S5 proteins. The presence of these newly identified mitochondrial ribosomal proteins are also investigated in the Drosophila melanogaster, Caenorhabditis elegans, and in the genomes of several fungi.
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ADN Complementario/genética , Mitocondrias/química , Proteoma/química , Proteínas Ribosómicas/química , Proteínas Ribosómicas/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Caenorhabditis elegans , Bovinos , Drosophila melanogaster , Escherichia coli , Hongos , Humanos , Espectrometría de Masas , Mitocondrias/ultraestructura , Datos de Secuencia Molecular , Subunidades de Proteína , Proteoma/metabolismo , Especificidad de la EspecieRESUMEN
Two proteins known to be involved in promoting apoptosis in mammalian cells have been identified as components of the mammalian mitochondrial ribosome. Proteolytic digestion of whole mitochondrial ribosomal subunits followed by analysis of the peptides present using liquid chromatography-tandem mass spectrometry revealed that the proapoptotic proteins, death-associated protein 3 (DAP3) and the programmed cell death protein 9, are both components of the mitochondrial ribosome. DAP3 has motifs characteristic of guanine nucleotide binding proteins and is probably the protein that accounts for the nucleotide binding activity of mammalian mitochondrial ribosomes. The observations reported here implicate mitochondrial protein synthesis as a major component in cellular apoptotic signaling pathways.
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Apoptosis , Proteínas de Ciclo Celular/metabolismo , Mitocondrias/metabolismo , Proteínas/metabolismo , Secuencia de Aminoácidos , Animales , Proteínas Reguladoras de la Apoptosis , Bovinos , Proteínas de Ciclo Celular/química , Humanos , Técnicas In Vitro , Espectrometría de Masas , Mitocondrias/fisiología , Datos de Secuencia Molecular , Prenilación de Proteína , Proteínas/química , Proteínas de Unión al ARN , Proteínas Ribosómicas/química , Proteínas Ribosómicas/metabolismo , Homología de Secuencia de AminoácidoRESUMEN
Identification of all the protein components of the small subunit (28 S) of the mammalian mitochondrial ribosome has been achieved by carrying out proteolytic digestions of whole 28 S subunits followed by analysis of the resultant peptides by liquid chromatography and tandem mass spectrometry (LC/MS/MS). Peptide sequence information was used to search the human EST data bases and complete coding sequences of the proteins were assembled. The human mitochondrial ribosome has 29 distinct proteins in the small subunit. Fourteen of this group of proteins are homologs of the Escherichia coli 30 S ribosomal proteins S2, S5, S6, S7, S9, S10, S11, S12, S14, S15, S16, S17, S18, and S21. All of these proteins have homologs in Drosophila melanogaster, Caenorhabditis elegans, and Saccharomyces cerevisiae mitochondrial ribosomes. Surprisingly, three variants of ribosomal protein S18 are found in the mammalian and D. melanogaster mitochondrial ribosomes while C. elegans has two S18 homologs. The S18 homologs tend to be more closely related to chloroplast S18s than to prokaryotic S18s. No mitochondrial homologs to prokaryotic ribosomal proteins S1, S3, S4, S8, S13, S19, and S20 could be found in the peptides obtained from the whole 28 S subunit digests or by analysis of the available data bases. The remaining 15 proteins present in mammalian mitochondrial 28 S subunits (MRP-S22 through MRP-S36) are specific to mitochondrial ribosomes. Proteins in this group have no apparent homologs in bacterial, chloroplast, archaebacterial, or cytosolic ribosomes. All but two of these proteins have a clear homolog in D. melanogaster while all but three can be found in the genome of C. elegans. Five of the mitochondrial specific ribosomal proteins have homologs in S. cerevisiae.
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Mitocondrias/química , Ribosomas/química , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Caenorhabditis elegans , Bovinos , Secuencia Conservada , Cristalografía por Rayos X , Bases de Datos Factuales , Drosophila melanogaster , Electroforesis en Gel Bidimensional , Escherichia coli/metabolismo , Etiquetas de Secuencia Expresada , Cromatografía de Gases y Espectrometría de Masas , Genoma , Humanos , Lisina/química , Espectrometría de Masas , Ratones , Modelos Moleculares , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Péptidos/química , ARN Mensajero/química , Saccharomyces cerevisiae , Homología de Secuencia de Aminoácido , Programas Informáticos , Thermus thermophilusRESUMEN
c-Abl is a nonreceptor tyrosine kinase that we have recently linked to growth factor receptor signaling. The c-Abl kinase is ubiquitously expressed and localizes to the cytoplasm, plasma membrane, cytoskeleton, and nucleus. Thus, c-Abl may regulate signaling processes in multiple subcellular compartments. Targeted deletion or mutation of c-Abl in mice results in a variety of phenotypes, including splenic and thymic atrophy and lymphopenia. Additionally, lymphocytes isolated from specific compartments of c-Abl mutant mice have reduced responses to a variety of stimuli and an increased susceptibility to apoptosis following growth factor deprivation. Despite these observations, little is known regarding the signaling mechanisms responsible for these phenotypes. We report here that splenic B cells from c-Abl-deficient mice are hyporesponsive to the proliferative effects of B cell Ag receptor (BCR) stimulation. The c-Abl kinase activity and protein levels are elevated in the cytosol following activation of the BCR in B cell lines. We show that c-Abl associates with and phosphorylates the BCR coreceptor CD19, and that c-Abl and CD19 colocalize in lipid membrane rafts. These data suggest a role for c-Abl in the regulation of B cell proliferation downstream of the BCR, possibly through interactions with CD19.
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Antígenos CD19/metabolismo , Linfocitos B/enzimología , Linfocitos B/inmunología , Proteínas Proto-Oncogénicas c-abl/metabolismo , Receptores de Antígenos de Linfocitos B/metabolismo , Animales , Animales no Consanguíneos , Linfocitos B/metabolismo , Detergentes , Activación Enzimática/genética , Activación Enzimática/inmunología , Humanos , Activación de Linfocitos/genética , Microdominios de Membrana/inmunología , Microdominios de Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Proto-Oncogénicas c-abl/biosíntesis , Proteínas Proto-Oncogénicas c-abl/deficiencia , Proteínas Proto-Oncogénicas c-abl/genética , Receptores de Antígenos de Linfocitos B/fisiología , Solubilidad , Especificidad por Sustrato/genética , Especificidad por Sustrato/inmunología , Células Tumorales Cultivadas , Regulación hacia Arriba/genética , Regulación hacia Arriba/inmunologíaRESUMEN
Receptor activator of NF-kappaB ligand (RANKL) is a type II transmembrane protein found on osteoblasts which functions as a major determinant of osteoclast differentiation and activation. RANKL mediates bone homeostasis through binding to the cognate ligand on osteoclasts, RANK, and a soluble decoy receptor, osteoprotegerin (OPG). We designed a construct encoding the extracellular domain of human RANKL that conformed to reports of native processing. To encourage folding and posttranslational modification of a normally membrane-inserted moiety, we expressed the RANKL truncate as a secreted protein using the signal sequence from OPG in a Trichoplusia ni cell line using a baculovirus expression vector. RANKL was purified by a three-step process including an OPG-Fc affinity column. SDS-PAGE and mass spectral analysis indicated that the protein was >99% pure and glycosylated. Circular dichroism spectra revealed that the protein exhibited structural elements similar to tumor necrosis factor-alpha. By BIAcore analysis, RANKL bound to OPG with an affinity of 6.7 nM. Sedimentation equilibrium analytical ultracentrifugation analyses established that our protein existed as a trimer. We conclude that our expressed human RANKL truncate is folded, is functional, and exhibits self-association consistent with other family members.
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Proteínas Portadoras/genética , Glicoproteínas de Membrana/genética , Secuencia de Aminoácidos , Proteínas Portadoras/química , Proteínas Portadoras/aislamiento & purificación , Línea Celular , Cromatografía Liquida , Dicroismo Circular , Clonación Molecular , Humanos , Espectrometría de Masas , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/aislamiento & purificación , Datos de Secuencia Molecular , Conformación Proteica , Procesamiento Proteico-Postraduccional , Ligando RANK , Receptor Activador del Factor Nuclear kappa-B , UltracentrifugaciónRESUMEN
OBJECTIVE: To identify a significant change in the laxity of the anterior cruciate ligament (ACL) in the competitive adolescent female athlete throughout the different phases of the menstrual cycle. DESIGN: Prospective, single-blinded 8-week study set during a winter sports season. SETTING: Suburban Ohio Division I high school. PARTICIPANTS: 26 members of gymnastics, soccer, track, tennis, and basketball teams. All participants were screened for normal menstrual cycles (26-30 days, menses 4-7 days long). MAIN OUTCOME MEASURES: KT-1000 arthrometer was used to measure laxity by performing repeated measures throughout an 8-week period. Measurements were taken before the athletes' workouts. The athlete charted the menstrual periods on a monthly calendar. The measurements were then grouped into the three phases of the menstrual cycle (follicular, ovulatory, and luteal) and averaged. RESULTS: Right knee laxity measured 4.98 mm follicular phase, 5.24 mm ovulatory, and 5.09 mm luteal. Left knee laxity measured 4.51 mm follicular, 4.43 mm ovulatory, and 4.62 mm luteal. There was no statistical difference among the three phases in the left (p = 0.9) and right (p = 0.7977). Additionally, left ACL laxity was significantly less in all three phases. We found no statistically significant variability in laxity among the five sports sampled (p > 0.63 to 0.10) and different ages (p = 0.404). CONCLUSIONS: We found an insignificant change in ACL laxity from follicular to luteal phases of the menstrual cycle. This indicates that no single phase of the menstrual cycle clinically affects the ACL more than the next. Although the presence of sex hormones-particularly estrogen-may indeed predispose females to higher ACL injury rates, we did not find any evidence that hormonal level changes equate with significant ACL laxity changes. We conclude that the menstrual cycle does not significantly affect ACL laxity in the competitive adolescent female athlete.
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Ligamento Cruzado Anterior/fisiología , Ciclo Menstrual/fisiología , Deportes , Adolescente , Femenino , Humanos , Ohio , Estudios Prospectivos , Instituciones Académicas , Método Simple CiegoRESUMEN
Mammalian mitochondrial small subunit ribosomal proteins were separated by two-dimensional polyacrylamide gel electrophoresis. The proteins in six individual spots were subjected to in-gel tryptic digestion. Peptides were separated by capillary liquid chromatography, and the sequences of selected peptides were obtained by electrospray tandem mass spectrometry. The peptide sequences obtained were used to screen human expressed sequence tag data bases, and complete consensus cDNAs were assembled. Mammalian mitochondrial small subunit ribosomal proteins from six different classes of ribosomal proteins were identified. Only two of these proteins have significant sequence similarities to ribosomal proteins from prokaryotes. These proteins correspond to Escherichia coli S10 and S14. Homologs of two human mitochondrial proteins not found in prokaryotes were observed in the genomes of Drosophila melanogaster and Caenorhabditis elegans. A homolog of one of these proteins was observed in D. melanogaster but not in C. elegans, while a homolog of the other was present in C. elegans but not in D. melanogaster. A homolog of one of the ribosomal proteins not found in prokaryotes was tentatively identified in the yeast genome. This latter protein is the first reported example of a ribosomal protein that is shared by mitochondrial ribosomes from lower and higher eukaryotes that does not have a homolog in prokaryotes.
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Proteínas de Drosophila , Mitocondrias/metabolismo , Proteoma/química , Proteínas Ribosómicas/química , Proteínas de Saccharomyces cerevisiae , Secuencia de Aminoácidos , Animales , Caenorhabditis elegans , Cromatografía Liquida , Secuencia de Consenso , ADN Complementario , Drosophila , Escherichia coli/metabolismo , Humanos , Mamíferos , Ratones , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/aislamiento & purificación , Proteoma/genética , Proteoma/aislamiento & purificación , Proteínas Ribosómicas/genética , Proteínas Ribosómicas/aislamiento & purificación , Saccharomyces cerevisiae , Alineación de Secuencia , Homología de Secuencia de Aminoácido , TripsinaRESUMEN
Sindbis virus contains two membrane glycoproteins, E1 and E2, which are organized into 80 trimers of heterodimers (spikes). These trimers form a precise T=4 icosahedral protein lattice on the surface of the virus. Very little is known about the organization of the E1 and E2 glycoproteins within the spike trimer. To gain a better understanding of how the proteins E1 and E2 are arranged in the virus membrane, we have used the techniques of limited proteolysis and amino acid chemical modification in combination with mass spectrometry. We have determined that at neutral pH the E1 protein regions that are accessible to proteases include domains 1-21 (region encompassing amino acids 1 to 21), 161-176, and 212-220, while the E2 regions that are accessible include domains 31-84, 134-148, 158-186, 231-260, 299-314, and 324-337. When Sindbis virus is exposed to low pH, E2 amino acid domains 99-102 and 262-309 became exposed while other domains became inaccessible. Many new E1 regions became accessible after exposure to low pH, including region 86-91, which is in the putative fusion domain of E1 of Semliki Forest virus (SFV) (M. C. Kielian et al., J. Cell Biol. 134:863-872, 1996). E1 273-287 and region 145-158 were also exposed at low pH. These data support a model for the structure of the alphavirus spike in which the E1 glycoproteins are centrally located as trimers which are surrounded and protected by the E2 glycoprotein. These data improve our understanding of the structure of the virus membrane and have implications for understanding the protein conformational changes which accompany the process of virus-cell membrane fusion.
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Glicoproteínas de Membrana/química , Virus Sindbis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Proteínas del Envoltorio Viral/química , Cápside/química , Cápside/metabolismo , Disulfuros/metabolismo , Concentración de Iones de Hidrógeno , Radioisótopos de Yodo/metabolismo , Glicoproteínas de Membrana/metabolismo , Pepsina A/metabolismo , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Serina Endopeptidasas/metabolismo , Tinción con Nitrato de Plata , Programas Informáticos , Propiedades de Superficie , Tripsina/metabolismo , Tirosina/metabolismo , Proteínas del Envoltorio Viral/metabolismoRESUMEN
Rasmussen's encephalitis (RE) is a rare disease of the central nervous system characterized by severe epileptic seizures, progressive degeneration of a single cerebral hemisphere, and autoimmunity directed against glutamate receptor subunit, GluR3. We report here the identification of high-titer autoantibodies directed against munc-18 in the serum of a single patient with RE previously shown to have anti-GluR3 antibodies. Munc-18 is an intracellular protein residing in presynaptic terminals, which is required for secretion of neurotransmitters. These findings are consistent with the possibility of intermolecular epitope spreading between GluR3, a postsynaptic cell surface protein, and munc-18, a presynaptic intracellular protein. Immune attack on these two proteins, which participate at distinct steps of synaptic transmission, could act in an additive or synergistic manner to impair synaptic function and lead to seizures and neuronal death.