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1.
Int J Cosmet Sci ; 37(5): 532-41, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25923177

RESUMEN

OBJECTIVE: Damage to hair from UV exposure has been well reported in the literature and is known to be a highly complex process involving initiation via absorption of UV light followed by formation and propagation of reactive oxygen species (ROS). The objective of this work was to understand these mechanisms, explain the role of copper in accelerating the formation of ROS and identify strategies to reduce the hair damage caused by these reactive species. METHODS: The location of copper in hair was measured by Transmission electron microscopy-(TEM) X-ray energy dispersive spectroscopy (XEDS) and levels measured by ICP-OES. Protein changes were measured as total protein loss via the Lowry assay, and MALDI ToF was used to identify the biomarker protein fragments. TBARS assay was used to measure lipid peroxide formation. Sensory methods and dry combing friction were used to measure hair damage due to copper and UV exposure and to demonstrate the efficacy of N,N' ethylenediamine disuccinic acid (EDDS) and histidine chelants to reduce this damage. RESULTS: In this work, a biomarker protein fragment formed during UV exposure is identified using mass spectrometry. This fragment originates from the calcium-binding protein S100A3. Also shown is the accelerated formation of this peptide fragment in hair containing low levels of copper absorbed from hair during washing with tap water containing copper ions. Transmission electron microscopy (TEM) X-ray energy dispersive spectroscopy (XEDS) studies indicate copper is located in the sulphur-poor endo-cuticle region, a region where the S100A3 protein is concentrated. A mechanism for formation of this peptide fragment is proposed in addition to the possible role of lipids in UV oxidation. A shampoo and conditioner containing chelants (EDDS in shampoo and histidine in conditioner) is shown to reduce copper uptake from tap water and reduce protein loss and formation of S100A3 protein fragment. In addition, the long-term consequences of UV oxidation and additional damage induced by copper are illustrated in a four-month wear study where hair was treated with a consumer relevant protocol of hair colouring treatments, UV exposure and regular shampoo and conditioning. CONCLUSIONS: The role of copper in accelerating UV damage to hair has been demonstrated as well as the ability of chelants such as EDDS and histidine in shampoo and conditioner products to reduce this damage.


Asunto(s)
Cobre/metabolismo , Cabello/efectos de la radiación , Rayos Ultravioleta , Secuencia de Aminoácidos , Cabello/metabolismo , Humanos , Microscopía Electrónica de Transmisión de Rastreo , Datos de Secuencia Molecular , Proteínas/química , Espectrometría de Masas en Tándem
2.
Int J Cosmet Sci ; 36(1): 32-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23962007

RESUMEN

OBJECTIVE: The objective of this work was to identify whether low levels of redox metals such as copper will accelerate damage to hair on exposure to UV irradiation and whether this damage can be prevented. METHODS: The methods used were proteomics to measure the protein damage via protein loss after different periods of exposure and mass spectroscopy methods to identify specific marker peptides that are specifically created by this type of damage. RESULTS: In this work, we have developed new insights into the mechanism of UV damage using these proteomic methods. A marker fragment in the hair protein loss extract was identified (m/z = 1279) that is unique to UV exposure and increases with time of UV exposure. We have also identified for the first time in hair the role of exogenous copper in increasing UV damage both in terms of total protein degradation and also increased formation of the marker fragment and proposed a mechanism of action. It has been demonstrated that shampoo treatment containing a chelant such as N,N'-ethylenediamine disuccinic acid (EDDS) reduced copper accumulation in hair. CONCLUSION: This work provides evidence for the role of copper in UV-induced damage to hair and strategies to reduce copper levels in hair using a chelant such as EDDS.


Asunto(s)
Cobre/fisiología , Cabello/efectos de la radiación , Rayos Ultravioleta , Humanos , Proteínas/efectos de la radiación , Proteómica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
3.
Klin Padiatr ; 225(1): 8-12, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23235928

RESUMEN

Standardized examinations of preterm infants are used to identify candidates for early intervention. We aimed to assess the predictive power and concurrent validity of the mental development index of the Bayley scales of infant development II (Bayley MDI) and the Griffiths scales developmental quotient (Griffiths DQ) in healthy term and preterm infants <1500 g birth weight without major perinatal complications.137 Infants (89 term, 48 preterm) were examined by both tests at a corrected age of 6, 12, and 22 months, and 114 went on to undergo Bayley assessments at 39 months.There were significant correlations between Bayley and Griffiths results at 6, 12, and 22 months (r=0.530, 0.714, and 0.833, respectively, p<0.001) but Bland Altman plots revealed major systematic bias at 6 months (Griffiths>Bayley, mean differences 14.3±9.8) and 22 months (Bayley>Griffiths, mean difference 5.2±13.9) and wide 95% limits of agreement at 6, 12 and 22 months (35.9%, 40.0%, and 52.4%, respectively). The agreement for a presumptive diagnosis of developmental impairment in the group of preterm infants between Bayley examinations obtained at 39 months corrected age (reference) and previous examinations was poor at 6, 12, and 22 months for both Bayley and Griffiths (Cohen's kappa for Griffiths: 0.225, 0.192, 0.369; for Bayley: 0.121, 0.316, 0.369, respectively).Caution should be exercised when interpreting results from standardized neurodevelopmental examinations obtained during the first 2 years of life in comparatively well preterm infants.


Asunto(s)
Discapacidades del Desarrollo/diagnóstico , Recién Nacido de Bajo Peso , Enfermedades del Prematuro/diagnóstico , Examen Neurológico/estadística & datos numéricos , Preescolar , Discapacidades del Desarrollo/clasificación , Discapacidades del Desarrollo/terapia , Intervención Educativa Precoz , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Enfermedades del Prematuro/clasificación , Enfermedades del Prematuro/terapia , Masculino , Examen Neurológico/normas , Psicometría/estadística & datos numéricos , Valores de Referencia , Reproducibilidad de los Resultados
5.
Protein Sci ; 1(6): 777-85, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1304918

RESUMEN

The disulfide pairings of the two Euplotes raikovi pheromones Er-1 and Er-2 have been determined by chemical and mass spectrometric analyses. Cystine-linked peptides from thermolytic digestions of the native molecules were purified by reverse-phase high performance liquid chromatography and identified in the known sequences to make the assignments. The same pairing, Cys(I)-Cys(IV), Cys(II)-Cys(VI), and Cys(III)-Cys(V), was found in both pheromones, suggesting that this pattern occurs commonly throughout this family of molecules. This arrangement of disulfides indicates that the three-dimensional structure is defined by three loops, which can vary in size and charge distribution from one pheromone to another.


Asunto(s)
Euplotes/fisiología , Proteínas de la Membrana/química , Feromonas/química , Proteínas Protozoarias/química , Secuencia de Aminoácidos , Animales , Cromatografía Líquida de Alta Presión , Cistina , Disulfuros/análisis , Espectrometría de Masas , Datos de Secuencia Molecular , Fragmentos de Péptidos/aislamiento & purificación , Conformación Proteica
6.
Sleep ; 11(1): 69-74, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3363272

RESUMEN

Renal abnormalities in patients with obstructive sleep apnea syndrome (OSAS) have not been previously described. Medical records of patients who had been evaluated for possible sleep apnea syndrome and had had complete polysomnograms and urinalyses were reviewed to determine the frequency of proteinuria. High-grade proteinuria (greater than or equal to 3+ on urinalysis) was found in 6 of the 34 patients with obstructive sleep apnea, but in none of 34 patients in a control group matched for sex, age, and weight. In three patients, proteinuria was in the nephrotic range (3.5 g/24 h). The weight (mean +/- SD) of the patients with obstructive sleep apnea (112.7 +/- 35.3 kg) was not significantly different from the control group (109.2 +/- 30.3 kg). Microscopic examination of renal tissue in one patient with OSAS showed minimal changes. In four patients who were followed for 3 years, proteinuria improved after therapy for sleep apnea syndrome. We suggest that proteinuria may not be uncommon in patients with severe obstructive sleep apnea syndrome and may be reversible with correction of the sleep apnea syndrome.


Asunto(s)
Síndrome Nefrótico/etiología , Proteinuria/etiología , Síndromes de la Apnea del Sueño/complicaciones , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Síndromes de la Apnea del Sueño/cirugía
7.
Med Klin Intensivmed Notfmed ; 109(2): 104-8, 2014 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-24589883

RESUMEN

BACKGROUND: Sepsis is a common, time-urgent emergency that is still associated with a high mortality and morbidity rate. A strong correlation between the onset of therapy and survival has been shown. With every hour of delay, survival decreases by 7.6 %. In 2001, four treatment goals that should be performed in the first 6 h of treatment were developed. These form the basis of early goal-directed therapy (EDGT) which is accepted as the standard of treatment for sepsis in the emergency department. OBJECTIVES: More than half of patients are admitted to the hospital by medical emergency services. Up to 40 % receive prehospital therapy with i.v. fluids and stabilization of vital signs according to the goals of EDGT. The diagnosis of sepsis is difficult if characteristic symptoms or parameters such as in the ST segment elevation myocardial infarction are lacking. However, 90 % of patients present with fever. CONCLUSIONS: Body temperature should always be assessed by paramedics. In addition, sepsis must always be considered as part of the differential diagnosis. If the suspicion cannot be ruled out, immediate therapy has to be initiated. Concerning the prehospital use of antibiotics, preliminary results of a study from the center of sepsis control and care in Jena, Germany, showed that this therapy form seems to be safe and effective, but further evaluation is necessary.


Asunto(s)
Servicios Médicos de Urgencia , Sepsis/terapia , Síndrome de Respuesta Inflamatoria Sistémica/terapia , Temperatura Corporal , Diagnóstico Diferencial , Fluidoterapia , Humanos , Planificación de Atención al Paciente , Pronóstico , Sepsis/diagnóstico , Sepsis/mortalidad , Tasa de Supervivencia , Síndrome de Respuesta Inflamatoria Sistémica/diagnóstico , Síndrome de Respuesta Inflamatoria Sistémica/mortalidad , Factores de Tiempo
10.
Anal Chem ; 64(22): 2804-14, 1992 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-1294007

RESUMEN

252Cf plasma desorption mass spectrometry has been used in the characterization of more than 100 synthetic porphyrins ranging in mass from 614 u for tetraphenylporphyrin to over 2000 u for some porphyrin model systems. In virtually every case, 252Cf plasma desorption mass spectrometry yielded an intense ionized molecule ion [M.+ and/or (M+H)+], irrespective of the groups appended to the porphyrin. The appended groups include carboxylic acids, amides, imides, chloroacetamides, Fmoc-protected amino acids, aromatic amines, nitriles, alkynes, alkenes, esters, active esters, benzyl ethers, acetals, dithioacetals, ketones, imines, phenols, quinone, hydroquinone, ferrocene, cyanine dyes, trimethylsilyl protecting groups, nitro groups, and combinations of these functionalities. Metalloporphyrins and porphyrin-porphyrin dimers are also analyzed with ease. Resolved isotopic peaks were observed for porphyrins with molecular weights below 1000, and unresolved isotopic peaks yielding average masses were observed for porphyrin compounds with higher molecular weights. The limited resolution in the higher molecular weight range does not lessen the utility of the method because the observation of the molecule ions [M.+ and/or (M+H)+] provides unambiguous evidence concerning the success of the synthesis. The 252Cf plasma desorption mass spectra of porphyrins are not complicated by chemical transformations. This method is ideally suited for rapid analysis of synthetic porphyrins and provides a powerful tool for chemists engaged in the synthesis of complex organic molecules.


Asunto(s)
Californio/sangre , Porfirinas/síntesis química , Espectrometría de Masas , Quinonas/síntesis química
11.
Biochem Biophys Res Commun ; 148(2): 827-33, 1987 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-3318825

RESUMEN

The original report assigning the pairing of neurophysin's 14 half-cystine residues (Schlesinger et al. (1972), Proc. Natl. Acad. Sci., U.S.A., 69,3350-3353) was based on an incorrect amino acid sequence. In the present study, re-investigation of the results of proteolytic fragmentation of bovine neurophysins indicates that the majority of the original assignments were incorrect. Three disulfide pairs are now assigned as Cys21-Cys44, Cys67-Cys85 and Cys74-Cys79. The pairing pattern indicates that neurophysin's variable carboxyl terminal region, separately encoded by the third gene exon, does not form a self-contained domain.


Asunto(s)
Neurofisinas , Secuencia de Aminoácidos , Animales , Bovinos , Cistina , Disulfuros/análisis , Espectrometría de Masas , Datos de Secuencia Molecular , Péptido Hidrolasas , Tripsina
12.
J Chromatogr ; 443: 285-98, 1988 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-3049649

RESUMEN

The combined use of ion-exchange, and reversed-phase high-performance liquid chromatography (HPLC) for the isolation of cystine-containing peptides from highly heterogeneous products of the proteolytic digestion of bovine neurophysins is described. The protein was sequentially cleaved by enzymes of decreasing specificity; the peptides released were initially fractionated by gel chromatography and then purified by HPLC. The purified peptides were analyzed by determination of their amino acid composition and mass spectrometry, supported by sequencing techniques. Three of the seven disulfide pairs of neurophysin have now been assigned. The usefulness of the combined use of HPLC and mass spectrometry in assigning these and the other disulfide pairs is illustrated.


Asunto(s)
Disulfuros/análisis , Neurofisinas/análisis , Secuencia de Aminoácidos , Aminoácidos/análisis , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Hidrólisis , Espectrometría de Masas , Datos de Secuencia Molecular , Péptidos/análisis , Subtilisinas , Tripsina
13.
Proc Natl Acad Sci U S A ; 86(2): 429-33, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2911588

RESUMEN

The pairing of the 14 half-cystine residues of bovine neurophysin was established by sequential proteolytic digestion. Purified released peptides and the residual disulfide-linked core were monitored at each step by use of amino acid analysis, gas-phase sequencing, and mass spectrometry. The approach included application of gas-phase sequencing to assign disulfide pairs in peptides containing multiple disulfides. The results demonstrate that neurophysin disulfides are paired in two distinct domains--an NH2 domain (residues 10-54) containing four disulfides and a COOH domain (residues 61-85) containing three disulfides. The specific disulfide bridges are Cys-10 to Cys-54, Cys-13 to Cys-27, Cys-21 to Cys-44, Cys-28 to Cys-34, Cys-61 to Cys-73, Cys-74 to Cys-79, and Cys-67 to Cys-85. The results place the internally duplicated segments of neurophysin (residues 12-31 and 60-77) in separate domains. Disulfide-pairing patterns within each domain are homologous with the exception of the Cys-10 to Cys-54 bond, which is unique to the NH2 domain and which links the two ends of this domain together. The potential role of the Cys-10 to Cys-54 bond in organizing the hormone-binding site is discussed.


Asunto(s)
Disulfuros/metabolismo , Neurofisinas/análisis , Secuencia de Aminoácidos , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Cromatografía por Intercambio Iónico , Cistina/metabolismo , Espectrometría de Masas , Metaloendopeptidasas/metabolismo , Datos de Secuencia Molecular , Neurofisinas/metabolismo , Mapeo Peptídico , Tripsina/metabolismo
14.
South Med J ; 77(4): 499-501, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6710206

RESUMEN

Many cardiorespiratory problems have been identified in patients with sleep apnea syndrome. Acute pulmonary edema as the primary feature of obstructive sleep apnea has recently been reported, and is thought to be caused by the effects of severe hypoxemia and/or extreme negative intrathoracic pressure. We have described another patient with sleep apnea syndrome who had pulmonary edema on at least three different occasions. Extremely high pulmonary artery pressure, paradoxic motion of the interventricular septum, and very low right heart ejection fraction were found. The paradoxic septal motion disappeared and the right heart ejection fraction increased after tracheostomy.


Asunto(s)
Edema Pulmonar/etiología , Síndromes de la Apnea del Sueño/complicaciones , Enfermedad Aguda , Adulto , Presión Sanguínea , Estudios de Seguimiento , Humanos , Masculino , Arteria Pulmonar/fisiopatología , Edema Pulmonar/fisiopatología , Edema Pulmonar/cirugía , Síndromes de la Apnea del Sueño/fisiopatología , Volumen Sistólico , Traqueotomía
15.
Ann Allergy ; 53(5): 410-3, 1984 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6497067

RESUMEN

A 31-year-old black male experienced severe recurrent urticaria and angioedema during meals. An abnormal sialographic pattern indicated submandibular sialoadenitis, and surgical excision of the gland resulted in complete resolution of the urticaria. This report describes the association of sialoadenitis and urticaria and possible mechanisms involved.


Asunto(s)
Enfermedades de las Glándulas Salivales/complicaciones , Sialadenitis/complicaciones , Urticaria/complicaciones , Adulto , Humanos , Masculino , Sialadenitis/terapia , Glándula Submandibular/patología , Glándula Submandibular/cirugía , Urticaria/terapia
16.
South Med J ; 79(9): 1061-3, 1986 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3749987

RESUMEN

Four patients with mild to moderate obstructive sleep apnea were monitored first in the supine posture to establish a diagnosis of obstructive sleep apnea (apnea indices 33, 12, 22, 36). A second polysomnogram, obtained while the patients slept in the lateral posture, showed a dramatic decrease in apnea (apnea indices 5, 0, 0.2, and 0) and snoring. Each patient had an enlarged uvula, which moved to the side in the lateral posture. We conclude that sleeping in the lateral posture may be therapeutic in some patients with obstructive sleep apneas.


Asunto(s)
Postura , Síndromes de la Apnea del Sueño/terapia , Adulto , Anciano , Femenino , Humanos , Masculino , Monitoreo Fisiológico/métodos , Síndromes de la Apnea del Sueño/complicaciones , Síndromes de la Apnea del Sueño/fisiopatología , Ronquido/etiología
17.
Biochemistry ; 40(38): 11630-42, 2001 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-11560514

RESUMEN

The involvement of red blood cell spectrin in the ubiquitination process was studied. Spectrin was found to form two ubiquitin-associated derivatives, a DTT-sensitive ubiquitin adduct and a DTT-insensitive conjugate, characteristic intermediate and final products of the ubiquitination reaction cascade. In addition to spectrin and ubiquitin, ubiquitin-activating enzyme (E1) and ATP were necessary and sufficient to form both the spectrin-ubiquitin adduct and conjugate. No exogenous ubiquitin-conjugating (E2) or ligase (E3) activities were required, suggesting that erythrocyte spectrin is an E2 ubiquitin-conjugating enzyme able to target itself. Both ubiquitin adduct and conjugate were linked to the alpha subunit of spectrin, suggesting that the ubiquitin-conjugating (UBC) domain and its target regions reside on the same subunit.


Asunto(s)
Membrana Eritrocítica/metabolismo , Ligasas/sangre , Espectrina/metabolismo , Ubiquitinas/metabolismo , Adenosina Trifosfato/metabolismo , Secuencia de Aminoácidos , Electroforesis en Gel de Poliacrilamida , Humanos , Ligasas/química , Ligasas/aislamiento & purificación , Espectrometría de Masas , Datos de Secuencia Molecular , Peso Molecular , Fragmentos de Péptidos/química , Espectrina/química , Espectrina/aislamiento & purificación , Enzimas Ubiquitina-Conjugadoras
18.
J Biol Chem ; 267(29): 20701-5, 1992 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-1383207

RESUMEN

We report the first molecular characterization of a precursor sequence for a small, Ca2+ channel blocking, peptide spider toxin, omega-agatoxin IA. By integrating information generated from a molecular genetic approach using agatoxin cDNAs with data provided from mass spectrometry of the mature toxin, we were able to deduce the likely mechanisms by which the toxin precursor peptide is processed to its mature heterodimeric form. A particularly interesting feature of the prepropeptide is the occurrence of two glutamate-rich sequences interposed between the signal sequences, the major peptide toxin, and the minor toxin peptide. Excision of the more distal glutamate-rich region appears to be signaled by flanking arginine residues but likely occurs only after a disulfide linkage has formed between the major and minor chains of the mature toxin. Our molecular genetic approach toward characterizing this toxin will allow us to quickly generate a series of spider sequences from which mature toxin structures can be deduced and eventually expressed. Additionally, this approach will provide insights into the evolutionary divergence observed among spider peptide toxins.


Asunto(s)
Precursores de Proteínas/química , Venenos de Araña/química , Agatoxinas , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bloqueadores de los Canales de Calcio/química , Vectores Genéticos , Sustancias Macromoleculares , Espectrometría de Masas , Modelos Estructurales , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Conformación Proteica , Precursores de Proteínas/genética , ARN/genética , ARN/aislamiento & purificación , Venenos de Araña/genética , Arañas/genética
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