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1.
J Patient Saf ; 19(1): 23-28, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36538338

RESUMO

OBJECTIVES: The goal of this project was to evaluate and improve the ordering, administration, documentation, and monitoring of enteral nutrition therapies within the inpatient setting in a Veteran's Health Administration system. METHODS: An interdisciplinary team of clinicians reviewed the literature for best practices and revised the process for enteral nutrition support for hospitalized veterans. Interventions included training staff, revising workflows to include scanning patients and products, including enteral nutrition orders within the medication administration record (MAR), and using the existing bar code medication administration system for administration, documentation, and monitoring. Baseline and postprocess improvement outcomes over a year period were collected and analyzed for quality improvement opportunities. RESULTS: Before process change, only 60% (33/55) of reviewed enteral nutrition orders were documented and 40% (22/55) were not documented in the intake flowsheet of the electronic health record. In the year after adding enteral nutrition therapies to the MAR and using bar code scanning, a total of 3807 enteral nutrition products were evaluated. One hundred percent of patients were bar code scanned, 3106/3807 (82%) products were documented as given, 447/3807 (12%) were documented as held (with comments), 12/3807 (<1%) were documented as missing/unavailable, and 242/3807 (6%) were documented as refused. CONCLUSIONS: Inclusion of enteral nutrition order sets on the MAR and using bar code scanning technology resulted in sustained improvements in safety, administration, and documentation of enteral therapies for hospitalized veterans.


Assuntos
Erros de Medicação , Veteranos , Humanos , Nutrição Enteral , Tecnologia , Documentação , Processamento Eletrônico de Dados/métodos , Atenção à Saúde
2.
Transplant Cell Ther ; 28(2): 70.e1-70.e5, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34838786

RESUMO

Following conventional i.v. hematopoietic stem cell transplantation (IV-HSCT), most of the hematopoietic stem cells get trapped in peripheral organs and do not reach the bone marrow niche. A promising approach to overcome this cell loss during the homing process seems to be the infusion of hematopoietic stem cells directly into the bone marrow cavity (intra-bone marrow [IBM]-HSCT). This study aimed to investigate the engraftment efficiency of IBM-HSCT compared with IV-HSCT following reduced-intensity conditioning in a canine HSCT model. Furthermore, the impact of 2 different graft infusion rates during IBM-HSCT on the engraftment was evaluated. Dogs received 4.5 Gy total body irradiation for conditioning at day -1 and 15 mg/kg cyclosporin A twice daily at days -1 to +35 as immunosuppression. The IV-HSCT group (n = 7) received unmodified bone marrow. The IBM-HSCT cohorts received buffy coat-enriched bone marrow that was applied into the humerus and femur simultaneously with an infusion time of either 10 minutes (IBM10; n = 8) or 60 minutes (IBM60; n = 7). Statistical analyses were performed using the Kruskal-Wallis test followed by the Mann-Whitney U test with Bonferroni correction for multiple comparisons. Statistical significance was declared at Bonferroni-adjusted P < .017. All dogs initially engrafted. One dog of the IBM10 cohort died at day +15 from infection. All 21 evaluable dogs developed a durable mixed donor chimerism over the course of 112 days. Engraftment kinetics did not differ significantly across the 3 groups. Leukocyte and platelet nadirs, as well as the durations of leukopenia and thrombocytopenia, were comparable in the 3 groups. Signs of toxicity for ingestion, body temperature, activity, and defecation did not show statistically significant differences among the 3 groups; only weight loss was greater in the IBM60 group compared with the IV group. IBM-HSCT following reduced-intensity conditioning resulted in an engraftment efficiency and hematopoietic recovery comparable to that seen with conventional IV-HSCT. In addition, modification of the graft infusion rate had no impact on engraftment and hematopoietic recovery in the canine IBM-HSCT model.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Animais , Medula Óssea , Cães , Antígenos HLA , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Condicionamento Pré-Transplante/métodos
3.
FEBS J ; 286(12): 2329-2340, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30817081

RESUMO

Photoactivatable fluorescent proteins (PA-FPs) are a powerful non-invasive tool in high-resolution live-cell imaging. They can be converted from an inactive to an active form by light, enabling the spatial and temporal trafficking of proteins and cell dynamics. PA-FPs have been previously generated by mutating selected residues in the chromophore or in its close proximity. A new strategy to generate PA-FPs is the genetic incorporation of unnatural amino acids (UAAs) containing photocaged groups using unique suppressor tRNA/aminoacyl-tRNA synthetase pairs. We set out to develop a photoactivatable GFP variant suitable for time-resolved structural studies. Here, we report the crystal structure of superfolder GFP (sfGFP) containing the UAA ortho-nitrobenzyl-tyrosine (ONBY) at position 66 and its spectroscopic characterization. Surprisingly, the crystal structure (to 2.7 Å resolution) reveals a dimeric domain-swapped arrangement of sfGFP66ONBY with residues 1-142 of one molecule associating with residues 148-234 from another molecule. This unusual domain-swapped structure supports a previously postulated GFP folding pathway that proceeds via an equilibrium intermediate.


Assuntos
Aminoácidos/genética , Proteínas de Fluorescência Verde/química , Conformação Proteica , Dobramento de Proteína , Aminoácidos/química , Aminoacil-tRNA Sintetases/genética , Cristalografia por Raios X , Escherichia coli/genética , Proteínas de Fluorescência Verde/genética , Methanocaldococcus/genética , Imagem Molecular/métodos , Mutação/genética , Fenilalanina/química , RNA de Transferência/química , RNA de Transferência/genética , Tirosina/genética
4.
J Obstet Gynecol Neonatal Nurs ; 47(5): 608-619, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30096281

RESUMO

OBJECTIVE: To determine if a healthy newborn's age in hours (3, 6, or 9 hours after birth) affects thermoregulatory status after the first bath as indicated by axillary and skin temperatures. DESIGN: Quasi-experimental, mixed-model (between subjects and within subjects) design with hours of age as the nonrepeated variable and prebath and postbath temperatures as the repeated variables. SETTING: Family-centered care unit at an urban hospital in the southwestern United States. PARTICIPANTS: Healthy newborns (N = 75) 37 weeks or more completed gestation. METHODS: Mothers chose time of first bath based on available time slots (n = 25 newborns in each age group). Research nurses sponge bathed the newborns in the mothers' rooms. Axillary temperature, an index of core temperature, was measured with a digital thermometer, and skin temperature, an index of body surface temperature, was measured with a thermography camera. Temperatures were taken before the bath; immediately after the bath; and 5, 30, 60, and 120 minutes after the bath. Immediately after the bath, newborns were placed in skin-to-skin care (SSC) for 60 or more minutes. RESULTS: We found a difference (p = .0372) in axillary temperatures between the 3- and 9-hour age groups, although this difference was not clinically significant (0.18 °F [0.10 °C]). We found no statistically significant differences in skin temperatures among the three age groups. Regardless of age group, axillary and skin temperatures initially decreased and then recovered after the bath. CONCLUSION: For up to 2 hours postbath, axillary and skin temperatures were not different between healthy newborns bathed at 3, 6, or 9 hours of age. Thermography holds promise for learning about thermoregulation, bathing, and SSC.


Assuntos
Banhos/métodos , Regulação da Temperatura Corporal , Temperatura Corporal/fisiologia , Cuidado do Lactente/métodos , Fatores Etários , Feminino , Voluntários Saudáveis , Humanos , Recém-Nascido , Masculino , Ensaios Clínicos Controlados não Aleatórios como Assunto , Temperatura , Fatores de Tempo
5.
AJP Rep ; 8(2): e74-e78, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29686936

RESUMO

Objective To evaluate the relationship between surgical outcomes and ultrasound measurement of placental extension beyond the cervical os in women with placenta previa. Study Design This is a retrospective cohort study of singleton pregnancies with placenta previa undergoing third-trimester ultrasound and delivering at our institution from 2002 through 2011. For study purposes, an investigator measured placental extension, defined as the placental distance from the internal os across the placenta continuing out to the lowest placental edge. If morbidly adherent placentation was suspected, women were excluded. Receiver operating characteristic (ROC) curves were developed for pertinent surgical outcomes, and multivariate analysis was performed to determine the placental extension with the best predictive discriminatory zone. Results In total, 157 women had placenta previa, ultrasound, and delivery data: 86 (55%) had a placental extension of <40 mm, and 71 (45%) had a placental extension of ≥40 mm. Women with placental extension of ≥40 mm had increased surgical time, blood loss > 2,000 mL, blood transfusion, and rate of peripartum hysterectomy. After multivariate analysis, only peripartum hysterectomy and surgical time > 90 minutes remained significant, p ≤ 0.05 and p ≤ 0.01, respectively. Conclusion In women with placenta previa, the placental extension ultrasound measurement of ≥40 mm is a predictor of adverse surgical outcomes.

6.
In Vivo ; 30(4): 427-32, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27381604

RESUMO

BACKGROUND: Graft-versus-host disease (GvHD) is an adverse effect following hematopoietic stem cell transplantation (HSCT) in humans. Dogs represent a key model organism for the development of treatment protocols for HSCT. However, detailed descriptions of canine GvHD and its treatment are rare. Herein we describe the development of canine GvHD and therapeutic intervention. MATERIALS AND METHODS: A female Beagle received an allogeneic HSCT from a dog leukocyte antigen-identical littermate (conditioning with 4.5 Gy total body irradiation; immunosuppression with cyclosporine A). RESULTS: GvHD developed at day +52 and was treated with methylprednisolone, cyclosporine A, antibiotics, antiviral medication and analgesics. The dog initially responded to the treatment but GvHD relapsed twice. Within one week after discontinuation of glucocorticoid, GvHD recurred resulting in inevitable euthanasia of the animal. CONCLUSION: GvHD represents a life-threatening disease after HSCT in canines. Immediate therapeutic treatment is indicated and even a successful initial treatment response does not necessarily prevent GvHD recurrence.


Assuntos
Sobrevivência de Enxerto/imunologia , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Histocompatibilidade , Tolerância Imunológica/imunologia , Animais , Terapia Combinada , Ciclosporina/uso terapêutico , Cães , Feminino , Doença Enxerto-Hospedeiro/patologia , Humanos , Imunossupressores/uso terapêutico , Transplante Homólogo , Irradiação Corporal Total
7.
Eur Radiol ; 24(10): 2482-90, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25030459

RESUMO

OBJECTIVES: To evaluate hepatobiliary magnetic resonance imaging (MRI) using Gd-EOB-DTPA in relation to various liver function tests in patients with liver disorders. METHODS: Fifty-one patients with liver disease underwent Gd-EOB-DTPA-enhanced liver MRI. Based on region-of-interest (ROI) analysis, liver signal intensity was calculated using the spleen as reference tissue. Liver-spleen contrast ratio (LSCR) and relative liver enhancement (RLE) were calculated. Serum levels of total bilirubin, gamma glutamyl transpeptidase (GGT), aspartate aminotransferase (AST), alanine aminotransferase (ALT), glutamate dehydrogenase (GLDH), lactate dehydrogenase (LDH), serum albumin level (AL), prothrombin time (PT), creatinine (CR) as well as international normalised ratio (INR) and model for end-stage liver disease (MELD) score were tested for correlation with LSCR and RLE. RESULTS: Pre-contrast LSCR values correlated with total bilirubin (r = -0.39; p = 0.005), GGT (r = -0.37; p = 0.009), AST (r = -0.38; p = 0.013), ALT (r = -0.29; p = 0.046), PT (r = 0.52; p < 0.001), GLDH (r = -0.55; p = 0.044), INR (r = -0.42; p = 0.003), and MELD Score (r = -0.53; p < 0.001). After administration of Gd-EOB-DTPA bilirubin (r = -0.45; p = 0.001), GGT (r = -0.40; p = 0.004), PT (r = 0.54; p < 0.001), AST (r = -0.46; p = 0.002), ALT (r = -0.31; p = 0.030), INR (r = -0.45; p = 0.001) and MELD Score (r = -0.56; p < 0.001) significantly correlated with LSCR. RLE correlated with bilirubin (r = -0.40; p = 0.004), AST (r = -0.38; p = 0.013), PT (r = 0.42; p = 0.003), GGT (r = -0.33; p = 0.020), INR (r = -0.36; p = 0.011) and MELD Score (r = -0.43; p = 0.003). CONCLUSIONS: Liver-spleen contrast ratio and relative liver enhancement using Gd-EOB-DTPA correlate with a number of routinely used biochemical liver function tests, suggesting that hepatobiliary MRI may serve as a valuable biomarker for liver function. The strongest correlation with liver enhancement was found for the MELD Score. KEY POINTS: • Relative enhancement (RLE) of Gd-EOB-DTPA is related to biochemical liver function tests. • Correlation of RLE with bilirubin, ALT, AST, GGT, INR and MELD Score is reverse. • The correlation of relative liver enhancement with prothrombin time is positive. • AST, ALT, GLDH, prothrombin time, INR and MELD Score correlate with pre-contrast liver-spleen contrast ratio. • Such biomarkers may help to evaluate liver function.


Assuntos
Biomarcadores/sangue , Gadolínio DTPA , Hepatopatias/patologia , Testes de Função Hepática/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/sangue , Bilirrubina/sangue , Meios de Contraste , Feminino , Glutamato Desidrogenase/sangue , Humanos , L-Lactato Desidrogenase/sangue , Hepatopatias/sangue , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Albumina Sérica/metabolismo , gama-Glutamiltransferase/sangue
8.
J Mol Biol ; 425(2): 222-31, 2013 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-23159557

RESUMO

Sulfur, a key contributor to biological reactivity, is not amendable to investigations by biological NMR spectroscopy. To utilize selenium as a surrogate, we have developed a generally applicable (77)Se isotopic enrichment method for heterologous proteins expressed in Escherichia coli. We demonstrate (77)Se NMR spectroscopy of multiple selenocysteine and selenomethionine residues in the sulfhydryl oxidase augmenter of liver regeneration (ALR). The resonances of the active-site residues were assigned by comparing the NMR spectra of ALR bound to oxidized and reduced flavin adenine dinucleotide. An additional resonance appears only in the presence of the reducing agent and disappears readily upon exposure to air and subsequent reoxidation of the flavin. Hence, (77)Se NMR spectroscopy can be used to report the local electronic environment of reactive and structural sulfur sites, as well as changes taking place in those locations during catalysis.


Assuntos
Cisteína/metabolismo , Redutases do Citocromo/química , Flavinas/metabolismo , Espectroscopia de Ressonância Magnética , Selenocisteína/metabolismo , Selenometionina/metabolismo , Catálise , Cristalografia por Raios X , Cisteína/química , Cisteína/genética , Redutases do Citocromo/genética , Redutases do Citocromo/metabolismo , Humanos , Mutação/genética , Oxirredução , Oxirredutases atuantes sobre Doadores de Grupo Enxofre , Conformação Proteica , Dobramento de Proteína , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
Cell Cycle ; 10(20): 3554-65, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22030623

RESUMO

Chronic hepatitis B virus (HBV) infection is the major risk for hepatocellular carcinomas (HCC). HBV X protein (HBx) and p53 tumor suppressor family interactions may be crucial for HCC induction. We compared p53 and p73 interactions with HBx in normal and HCC tumor cell lines differing in their p53 status. In the latter, HBx was pro-apoptotic but exhibited opposite effects in non-tumor cells. In these normal cells, p53 and p73 were retained in the cytoplasm. In hepatoma cells, however, HBx led to nuclear translocation of p53 and p73, followed by enhanced transactivation of p53-dependent promoters. The nuclear transfer of p53, but not of p73, was abrogated by protein kinase C inhibitor Gö6976. HBx overexpression in HCC cells led to strong p53 phosphorylation at Ser15, but not in non-tumor cells. Our results define ATM kinase as mediator for HBx-induced p53 phosphorylation. While HBx promotes cell death in p53/p73-positive hepatoma cells also in presence of increased levels of the oncogenic ΔTAp73 isoform, it significantly potentiates ΔTAp73-mediated proliferation and malignant transformation of fibroblasts. Our data suggest that prevention of apoptosis in normal cells by HBx through inhibition of pro-apoptotic p53 family members via direct interaction and coaction with anti-apoptotic ΔTAp73 seems to be the key element in the decision in favor of cell survival. The complex cell context-dependent interactions between p53 family members and HBx in the regulation of apoptosis may be essential in HBV-induced HCC and anticancer therapy.


Assuntos
Apoptose/fisiologia , Carcinoma Hepatocelular/etiologia , Proteínas de Ligação a DNA/metabolismo , Vírus da Hepatite B/metabolismo , Hepatite B Crônica/complicações , Neoplasias Hepáticas/etiologia , Proteínas Nucleares/metabolismo , Transativadores/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Carbazóis , Carcinoma Hepatocelular/metabolismo , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Primers do DNA/genética , Citometria de Fluxo , Imunofluorescência , Hepatite B Crônica/metabolismo , Humanos , Imunoprecipitação , Neoplasias Hepáticas/metabolismo , Camundongos , Microscopia Confocal , Modelos Biológicos , Células NIH 3T3 , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Proteína Tumoral p73 , Proteínas Virais Reguladoras e Acessórias
11.
J Biol Chem ; 286(2): 1014-24, 2011 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-21059654

RESUMO

The metabolic pathways that are involved in regulating insulin secretion from pancreatic ß-cells are still incompletely understood. One potential regulator of the metabolic phenotype of ß-cells is the transcription factor aryl hydrocarbon receptor nuclear translocator (ARNT)/hypoxia-inducible factor (HIF)-1ß. ARNT/HIF-1ß levels are profoundly reduced in islets obtained from type 2 diabetic patients. However, no study to date has investigated key pathways involved in regulating insulin release in ß-cells that lack ARNT/HIF-1ß. In this study, we confirm that siRNA-mediated knockdown of ARNT/HIF-1ß inhibits glucose-stimulated insulin secretion. We next investigated the metabolic consequence of the loss of ARNT/HIF-1ß knockdown. We demonstrate that ß-cells with reduced ARNT/HIF-1ß expression levels exhibit a 31% reduction in glycolytic flux without significant changes in glucose oxidation or the ATP:ADP ratio. Metabolic profiling of ß-cells treated with siRNAs against the ARNT/HIF-1ß gene revealed that glycolysis, anaplerosis, and glucose-induced fatty acid production were down-regulated, and all are key events involved in glucose-stimulated insulin secretion. In addition, both first and second phase insulin secretion in islets were significantly reduced after ARNT/HIF-1ß knockdown. Together, our data suggest an important role for ARNT/HIF-1ß in anaplerosis, and it may play a critical role in maintaining normal secretion competence of ß-cells.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Linhagem Celular Tumoral , Ciclo do Ácido Cítrico/fisiologia , Diabetes Mellitus Tipo 2/genética , Ácidos Graxos não Esterificados/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Perfilação da Expressão Gênica , Glucose/farmacologia , Células Secretoras de Insulina/citologia , Insulinoma , Metabolômica , Oxirredução , Neoplasias Pancreáticas , Via de Pentose Fosfato/fisiologia , RNA Interferente Pequeno , Ratos
12.
Biochemistry ; 49(31): 6737-45, 2010 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-20593814

RESUMO

The sulfhydryl oxidase augmenter of liver regeneration (ALR) binds FAD in a helix-rich domain that presents a CxxC disulfide proximal to the isoalloxazine ring of the flavin. Head-to-tail interchain disulfide bonds link subunits within the homodimer of both the short, cytokine-like, form of ALR (sfALR), and a longer form (lfALR) which resides in the mitochondrial intermembrane space (IMS). lfALR has an 80-residue N-terminal extension with an additional CxxC motif required for the reoxidation of reduced Mia40 during oxidative protein folding within the IMS. Recently, Di Fonzo et al. [Di Fonzo, A., Ronchi, D., Lodi, T., Fassone, E., Tigano, M., Lamperti, C., Corti, S., Bordoni, A., Fortunato, F., Nizzardo, M., Napoli, L., Donadoni, C., Salani, S., Saladino, F., Moggio, M., Bresolin, N., Ferrero, I., and Comi, G. P. (2009) Am. J. Hum. Genet. 84, 594-604] described an R194H mutation of human ALR that led to cataract, progressive muscle hypotonia, and hearing loss in three children. The current work presents a structural and enzymological characterization of the human R194H mutant in lf- and sfALR. A crystal structure of human sfALR was determined by molecular replacement using the rat sfALR structure. R194 is located at the subunit interface of sfALR, close to the intersubunit disulfide bridges. The R194 guanidino moiety participates in three H-bonds: two main-chain carbonyl oxygen atoms (from R194 itself and from C95 of the intersubunit disulfide of the other protomer) and with the 2'-OH of the FAD ribose. The R194H mutation has minimal effect on the enzyme activity using model and physiological substrates of short and long ALR forms. However, the mutation adversely affects the stability of both ALR forms: e.g., by decreasing the melting temperature by about 10 degrees C, by increasing the rate of dissociation of FAD from the holoenzyme by about 45-fold, and by strongly enhancing the susceptibility of sfALR to partial proteolysis and to reduction of its intersubunit disulfide bridges by glutathione. Finally, a comparison of the TROSY-HSQC 2D NMR spectra of wild-type sfALR and its R194H mutant reveals a significant increase in conformational flexibility in the mutant protein. In sum, these in vitro data document the major impact of the seemingly conservative R194H mutation on the stability of dimeric ALR and complement the in vivo observations of Di Fonzo et al.


Assuntos
Redutases do Citocromo/química , Doenças Musculares/genética , Mutação de Sentido Incorreto , Animais , Criança , Redutases do Citocromo/genética , Estabilidade Enzimática , Humanos , Mutação de Sentido Incorreto/fisiologia , Oxirredutases atuantes sobre Doadores de Grupo Enxofre , Maleabilidade , Conformação Proteica , Multimerização Proteica , Ratos
13.
Mil Med ; 173(10): 954-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19160612

RESUMO

This article is intended to help guide personnel chosen to lead military humanitarian missions. Suggestions for various stages of mission planning and execution are provided.


Assuntos
Altruísmo , Missões Médicas , Medicina Militar , Militares , Socorro em Desastres , Humanos , Estados Unidos
14.
J Mol Biol ; 373(1): 211-8, 2007 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-17765922

RESUMO

Protein conformational stability is an important concern in many fields. Here, we describe a strategy for significantly increasing conformational stability by optimizing beta-turn sequence. Proline and glycine residues are statistically preferred at several beta-turn positions, presumably because their unique side-chains contribute favorably to conformational stability in certain beta-turn positions. However, beta-turn sequences often deviate from preferred proline or preferred glycine. Therefore, our strategy involves replacing non-proline and non-glycine beta-turn residues with preferred proline or preferred glycine residues. Here, we develop guidelines for selecting appropriate mutations, and present results for five mutations (S31P, S42G, S48P, T76P, and Q77G) that significantly increase the conformational stability of RNase Sa. The increases in stability ranged from 0.7 kcal/mol to 1.3 kcal/mol. The strategy was successful in overlapping or isolated beta-turns, at buried (up to 50%) or completely exposed sites, and at relatively flexible or inflexible sites. Considering the significant number of beta-turn residues in every globular protein and the frequent deviation of beta-turn sequences from preferred proline and preferred glycine residues, this simple, efficient strategy will be useful for increasing the conformational stability of proteins.


Assuntos
Estrutura Secundária de Proteína , Glicina/química , Glicina/metabolismo , Modelos Moleculares , Mutação , Prolina/química , Prolina/metabolismo , Termodinâmica
15.
Hum Vaccin ; 3(4): 127-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17643066

RESUMO

Keloids are scars that extend beyond the original wound boundaries. They typically occur in darker skinned individuals with a familial tendency. Keloid formation has occurred after vaccination with bacilli Calmette-Guerin (BCG), small pox and hepatitis B vaccinations. We report the case of a 45-year-old female patient who developed extensive keloidal scars on her bilateral upper arms beginning in childhood after routine vaccinations. These keloids progressed with additional vaccines given at the same sites. Keloidal scars develop in anatomic areas exposed to increased skin tension as was seen in this patient. Treatment of these keloids is difficult but typically involves surgical excision, cryotherapy, radiation and intralesional and topical corticosteroids.


Assuntos
Queloide/etiologia , Vacinação/efeitos adversos , Adulto , Pré-Escolar , Feminino , Flurandrenolona/uso terapêutico , Humanos , Queloide/tratamento farmacológico , Queloide/cirurgia , Pessoa de Meia-Idade
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