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1.
Issues Ment Health Nurs ; 41(2): 138-145, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31322982

RESUMO

The expanding practice of multi-disciplinary care to address the complex nature of Autism Spectrum Disorder (ASD) suggests that there is a need for a means of coordinating care that transcends the disciplinary distinctions of relevant ASD treatment providers. As ASD services become more specialized, there is a growing need for effective care coordination with providers across the systems of care. Nursing professionals are ideally qualified to support families affected by ASD, as they provide a necessary holistic lens of health and wellbeing to obtain the appropriate treatments. Solution-focused brief therapy has been applied to a growing number of clinical settings, indicating solution-focused techniques are applicable to the various contexts associated with ASD treatments. We provide a case presentation to demonstrate a solution-focused approach to address ASD-related concerns within the family that are generalizable to coordination of care.


Assuntos
Transtorno do Espectro Autista/psicologia , Transtorno do Espectro Autista/terapia , Equipe de Assistência ao Paciente/organização & administração , Psicoterapia Breve/organização & administração , Adolescente , Criança , Humanos , Masculino
2.
Clin Exp Allergy ; 47(11): 1456-1467, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28703865

RESUMO

BACKGROUND: Atopic dermatitis (AD), psoriasis (PS), and contact dermatitis (CD) are common skin diseases, characterized by barrier disruption and systemic inflammation, with unique epidermal signatures and common inflammatory pathways identified by transcriptomic profiling. This study profiled proteomic signatures in serum from subjects with AD, PS, and CD compared with healthy controls (HC). OBJECTIVE: Identify unique proteomic signatures to distinguish between inflammatory diseases with similar epidermal disruption and overlapping epithelial inflammation. METHODS: Sera from 20 subjects with moderate to severe AD, 10 subjects with CD, 12 subjects with moderate to severe PS, 10 subjects with both AD and CD, and 10 HC with no history of skin disease was analysed using high-throughput proteomic analysis that detects expression of 1129 protein targets. Protein expression was compared between disease and HC, and across diseases for statistical significance (fold change≥1.5 and false discovery rate≤0.05), to identify unique proteomic signatures for each disease. RESULTS: Complement C5A anaphylatoxin (C5A), lipopolysaccharide binding protein (LBP), C-reactive protein (CRP), ILT-4, C-C motif ligand 18 (PARC), and sialic acid-binding Ig-like lectin 14 (SIG14) were significantly modulated in all three diseases compared with HC. We identified unique signatures for AD (Immunoglobulin E (IgE), thymus- and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC)), CD (10 proteins), and PS (kynureninase (KYNU)). Proteomic profiling in subjects with both AD and CD identified additional dysregulated proteins compared with subjects with either condition alone, indicating an exacerbated inflammation reaction. CONCLUSIONS AND CLINICAL RELEVANCE: Unique sera proteomic signatures may distinguish between inflammatory skin diseases despite similar epidermal barrier disruption and epithelial inflammation. This may provide insight into disease pathogenesis, diagnosis, and therapeutic intervention in difficult-to-treat subjects.


Assuntos
Dermatite Atópica/imunologia , Dermatite Atópica/metabolismo , Proteoma , Proteômica , Dermatopatias/metabolismo , Estudos de Casos e Controles , Análise por Conglomerados , Dermatite de Contato/imunologia , Dermatite de Contato/metabolismo , Feminino , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Mediadores da Inflamação/sangue , Mediadores da Inflamação/metabolismo , Masculino , Proteômica/métodos , Dermatopatias/etiologia
3.
Allergy ; 70(8): 887-96, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25879391

RESUMO

Atopic dermatitis (AD) is a debilitating disease that significantly alters the quality of life for one in four children and one in 10 adults. Current management of AD utilizes combinations of treatments to symptomatically alleviate disease by suppressing the inflammatory response and restoring barrier function in the skin, reducing disease exacerbation and flare, and preventing secondary skin infections. Resolution is temporary and long-term usage of these treatments can be associated with significant side-effects. Antibody therapies previously approved for inflammatory diseases have been opportunistically evaluated in patients with atopic dermatitis; however, they often failed to demonstrate a significant clinical benefit. Monoclonal antibodies currently in development offer hope to those individuals suffering from the disease by specifically targeting immune and molecular pathways important for the pathogenesis of atopic dermatitis. Here, we review the underlying biological pathways and the state of the art in therapeutics in AD.


Assuntos
Terapia Biológica/tendências , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/imunologia , Qualidade de Vida , Dermatite Atópica/psicologia , Feminino , Previsões , Humanos , Imunoterapia/tendências , Masculino , Índice de Gravidade de Doença , Pele/efeitos dos fármacos , Pele/imunologia , Resultado do Tratamento
4.
Plant Dis ; 98(1): 32-42, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30708590

RESUMO

Detection and quantification of airborne ascospores as a component of the Sclerotinia rot of carrot (SRC) forecast model is currently accomplished using the blue plate test (BPT), which uses Sclerotinia semiselective medium (SSM). A quantitative polymerase chain reaction (qPCR) assay was developed to reduce the time to specifically quantify ascospores of Sclerotinia sclerotiorum from air samples collected using a Burkard Multi-Vial Cyclone Sampler. The qPCR assay was highly sensitive and detected DNA from 0.5 to 5 × 104 ascospores within a linear range (R2 = 0.99). The qPCR assay was used to quantify ascospores of S. sclerotiorum in air samples collected over three growing seasons. Initial SRC disease was observed 8 and 34 days following detection of 9.5 and 2 ascospores m-3 of air, respectively. Results from air samples collected using an Andersen N6 Sampler and the qPCR assay were compared with the BPT. Ascospore counts from a Burkard Sampler coupled with the qPCR assay and the BPT followed similar trends. In general, fewer ascospores were detected and bioaerosol sampling efficiency was low using an Anderson Sampler. Three days were required to confirm the number of ascospores using SSM in the BPT and with an Andersen Sampler, whereas results from a Burkard Sampler coupled with the qPCR assay can provide results within 5 h of air sampling. The choice of method will depend on the available resources.

5.
Plant Dis ; 98(12): 1695-1701, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30703878

RESUMO

Rhizoctonia solani is a damaging soilborne pathogen, which affects most field crops in the Canadian provinces of Alberta, Manitoba, and Saskatchewan. The objective of this study was to conduct a phylogenetic comparison of isolates of R. solani collected from a previous survey in the major canola- and wheat-growing regions of western Canada. A total of 128 multinucleate isolates from a previous survey were identified by internal transcribed spacer (ITS) sequence and compared to anastomosis group (AG) results. The multinucleate isolates of R. solani were grouped into eight distinct clades. Each clade corresponded to a specific AG with the exception of two distinct clades that were observed for isolates classified as AG 2-1 by anastomosis testing. While most isolates of AG 5 clustered together according to ITS sequences, three isolates classified by anastomosis grouping as AG 5 grouped with AG 2-1, AG 4, and a binucleate Rhizoctonia sp. in the phylogenetic analysis. In most instances, the results from AG tests were consistent with ITS sequence, but there were still several cases where isolates were inconsistently classified or failed to undergo anastomosis with any of the tester strains used in this study. This provides support for the use of the ITS region as a valuable tool for rapid identification of R. solani isolates to their respective AGs.

6.
Clin Biochem ; 116: 105-112, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37100108

RESUMO

OBJECTIVES: Multiple sclerosis is diagnosed based on clinical and laboratory findings, including cerebrospinal fluid (CSF) oligoclonal banding (OCB) analysis. The lack of updated CSF OCB laboratory guidelines in Canada has likely led to variation in processes and reporting across clinical laboratories. As a first step to developing harmonized laboratory recommendations, we examined current CSF OCB processes, reporting, and interpretation across all Canadian clinical laboratories currently performing this test. DESIGN AND METHODS: A survey of 39 questions was sent to clinical chemists at all 13 Canadian clinical laboratories performing CSF OCB analysis. The survey included questions regarding quality control processes, reporting practices for CSF gel electrophoresis pattern interpretation, and associated tests and calculated indices. RESULTS: The survey response rate was 100%. Most (10/13) laboratories use ≥2 CSF-specific bands (2017 McDonald Criteria) as their CSF OCB positivity cut-off and only 2/13 report the number of bands with every report. Most (8/13 and 9/13) laboratories report an inflammatory response pattern and monoclonal gammopathy pattern, respectively. However, the process for reporting and/or confirming a monoclonal gammopathy varies widely. Variation was observed for reference intervals, units, and the panel of reported associated tests and calculated indices. The maximum acceptable time interval between paired CSF and serum collections varied from 24 h to no limit. CONCLUSIONS: Profound variation exists in processes, reporting, and interpretation of CSF OCB and associated tests and indices across Canadian clinical laboratories. Harmonization of CSF OCB analysis is required to ensure continuity and quality of patient care. Our detailed assessment of current practice variation highlights the need for clinical stakeholder engagement and further data analysis to support optimal interpretation and reporting practices, which will aid in developing harmonized laboratory recommendations.


Assuntos
Gamopatia Monoclonal de Significância Indeterminada , Esclerose Múltipla , Paraproteinemias , Humanos , Laboratórios Clínicos , Canadá , Bandas Oligoclonais , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/líquido cefalorraquidiano
7.
Clin Biochem ; 121-122: 110678, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37866698

RESUMO

BACKGROUND: LDL-C, a cardiovascular disease risk assessment biomarker, is commonly calculated using the Friedewald equation. The NIH equation overcomes several limitations of the Friedewald equation. Consistent with the Canadian Society of Clinical Chemists (CSCC) lipid reporting recommendations, we assessed the NIH LDL-C equation in Alberta prior to its provincial implementation. METHODS: 1-year (01/01/2021-12/31/2021) of lipid results (n = 1,486,584 after data cleaning) were obtained from five analytical instrument groups used across Alberta. Analyses were performed on all data and after separating by age, analytical instrument group, and fasting status. The correlation between Friedewald- and NIH-calculated LDL-C and between Friedewald- and NIH-calculated LDL-C difference and each lipid parameter, was determined. The frequency of unreportable/inaccurate LDL-C results was compared between the two equations. The concordance between the two equations and with non-HDL-C was determined at LDL-C thresholds. Lastly, LDL-C calculated by Friedewald, NIH, and Martin-Hopkins equations was compared to density-gradient ultracentrifugation. RESULTS: Friedewald- and NIH-calculated LDL-C exhibit the strongest correlation when triglycerides ≤ 4.52 mmol/L. The difference between Friedewald- and NIH-calculated LDL-C increases with decreasing LDL-C concentration. The NIH equation yields fewer inaccurate results (0.35 % vs. 22.0 %). The percent agreement between equations was > 96 % at all LDL-C thresholds, suggesting most patients will not require treatment changes. NIH-calculated LDL-C exhibited better agreement with non-HDL-C when triglycerides ≤ 9.04 mmol/L and better correlated with LDL-C measured by ultracentrifugation (r2 = 0.926 vs. 0.775 (Friedewald) and 0.863 (Martin-Hopkins)). Results were consistent across age, analytical instrument group, and fasting status. CONCLUSIONS: Our findings demonstrate the benefits of implementing the NIH equation across Alberta.


Assuntos
LDL-Colesterol , Humanos , LDL-Colesterol/análise , Alberta , Triglicerídeos , Biomarcadores , Ultracentrifugação
8.
Clin Biochem ; 118: 110589, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37236295

RESUMO

BACKGROUND: Hemoglobinopathies include thalassemia syndromes, where production of one or more globin subunits of hemoglobin (Hb) is reduced, and structural Hb variants. Over 1000 disorders of Hb synthesis and/or structure have been identified and characterized, with phenotypes ranging from having severe clinical manifestations to clinically silent. Various analytical methods are used to phenotypically detect Hb variants. However, molecular genetic analysis is a more definitive method for Hb variant identification. CASE REPORT: Here, we report a case of a 23-month-old male with results from capillary electrophoresis, gel electrophoresis (acid and alkaline), and high-performance liquid chromatography most consistent with HbS trait. Specifically, capillary electrophoresis showed slightly elevated HbF and HbA2, HbA of 39.4% and HbS of 48.5%. The HbS percentage was consistently higher than expected (typically 30-40%) for HbS trait with no concurrent thalassemic indices. The patient has not experienced any clinical complications due to the hemoglobinopathy and he is thriving. CONCLUSION: Molecular genetic analysis revealed the presence of compound heterozygosity for HbS and Hb Olupona. Hb Olupona is an extremely rare beta-chain variant that appears as HbA on all three common methods used for phenotypic Hb analysis. When the fractional concentration of Hb variants is unusual, more definitive methods should be used, such as mass spectrometry or molecular genetic testing. In this case, incorrectly reporting this result as HbS trait is unlikely to have a significant clinical impact, as current evidence suggests Hb Olupona is not a clinically significant variant.


Assuntos
Hemoglobinopatias , Hemoglobinas Anormais , Talassemia , Masculino , Humanos , Hemoglobinas Anormais/genética , Hemoglobinopatias/diagnóstico , Hemoglobinopatias/genética , Talassemia/genética , Hemoglobina A2 , Eletroforese Capilar/métodos
9.
Cell Microbiol ; 10(4): 958-84, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18031307

RESUMO

The biogenesis of the Salmonella-containing vacuole within mammalian cells has been intensively studied over recent years. However, the ability of Salmonella to sense and adapt to the intracellular environment of different types of host cells has received much less attention. To address this issue, we report the transcriptome of Salmonella enterica serovar Typhimurium SL1344 within epithelial cells and show comparisons with Salmonella gene expression inside macrophages. We report that S. Typhimurium expresses a characteristic intracellular transcriptomic signature in response to the environments it encounters within different cell types. The signature involves the upregulation of the mgtBC, pstACS and iro genes for magnesium, phosphate and iron uptake, and Salmonella pathogenicity island 2 (SPI2). Surprisingly, in addition to SPI2, the invasion-associated SPI1 pathogenicity island and the genes involved in flagellar biosynthesis were expressed inside epithelial cells at later stages of the infection, while they were constantly downregulated in macrophage-like cells. To our knowledge, this is the first report of the simultaneous transcription of all three Type Three Secretion Systems (T3SS) within an intracellular Salmonella population. We discovered that S. Typhimurium strain SL1344 was strongly cytotoxic to epithelial cells after 6 h of infection and hypothesize that the time-dependent changes in Salmonella gene expression within epithelial cells reflects the bacterial response to host cells that have been injured by the infection process.


Assuntos
Células Epiteliais/microbiologia , Salmonella typhimurium/crescimento & desenvolvimento , Salmonella typhimurium/genética , Transcrição Gênica , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Células CACO-2 , Linhagem Celular , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos/genética , Células HeLa , Humanos , Imuno-Histoquímica , Macrófagos/citologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Salmonella typhimurium/ultraestrutura
10.
J Appl Microbiol ; 105(5): 1239-45, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18399976

RESUMO

AIMS: The aims of the current study were to explore the site of bacterial attachment to vegetable tissues and to investigate the hypothesis that Salmonella must be living in order to attach to this site(s). METHODS AND RESULTS: Scanning electron micrographs of intact potato cells showed that Salm. serotype Typhimurium attached to cell-wall junctions; suggesting a high-level of site selectivity. Inactivation of Salm. Typhimurium using heat, ethanol, formalin or Kanamycin resulted in cells that could be no longer attached to these sites. Attachment of a Gfp(+) strain of Salm. Typhimurium to cell-wall material (CWM) was examined via flow cytometric analysis. Only live Salm. Typhimurium attached to the CWM. CONCLUSIONS: Salmonella serotype Typhimurium must be metabolically active to ensure attachment to vegetable tissues. Attachment preferentially occurs at the plant cell-wall junction and the cell-wall components found here, including pectate, may provide a receptor site for bacterial attachment. SIGNIFICANCE AND IMPACT OF THE STUDY: Further studies into individual plant cell-wall components may yield the specific bacterial receptor site in vegetable tissues. This information could in turn lead to the development of more targeted and effective decontamination protocols that block this site of attachment.


Assuntos
Aderência Bacteriana/fisiologia , Parede Celular/microbiologia , Salmonella typhimurium/fisiologia , Solanum tuberosum/microbiologia , Contagem de Colônia Microbiana , Etanol , Citometria de Fluxo/métodos , Microbiologia de Alimentos , Microscopia Eletrônica de Varredura , Pectinas/análise , Salmonella typhimurium/crescimento & desenvolvimento , Solanum tuberosum/ultraestrutura , Temperatura
11.
J Mol Biol ; 180(3): 399-416, 1984 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-6335532

RESUMO

We have determined the nucleotide sequence of gene 23 of bacteriophage T4 by the methods of Maxam and Gilbert and of Sanger. The identities of approximately 80% of the amino acid residues of the major capsid protein which is encoded by gene 23 were determined additionally by Edman degradation of the intact protein and its peptides. Fifteen gene 23 amber mutation sites have been located within the sequence, and the 3' transcription termination site for genes 21, 22 and 23 has been identified.


Assuntos
Genes Virais , Biossíntese de Proteínas , Fagos T/genética , Proteínas Virais , Sequência de Aminoácidos , Aminoácidos/análise , Sequência de Bases , Códon , DNA Viral , Mutação , Plasmídeos , RNA Mensageiro , RNA Viral , Regiões Terminadoras Genéticas , Transcrição Gênica
12.
Arch Pediatr Adolesc Med ; 152(8): 727-33, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9701129

RESUMO

OBJECTIVE: To determine American teenagers' awareness of and knowledge about emergency contraceptive pills and their likelihood to use them. METHODS: We conducted a nationally representative telephone survey between March 28, 1996, and May 5, 1996, of 1510 teenagers (757 girls and 753 boys), aged 12 to 18 years, living in the continental United States in households with telephones. The sample overrepresented African American, Latino, and low-income teenagers. The error attributable to sampling and other random effects for the total sample is +/-3 percentage points at the 95% confidence level. RESULTS: Of the 1510 teenagers, only about one quarter (23%) were aware that "anything" could be done after unprotected sex to prevent pregnancy. Slightly more (28%) had heard of "morning-after pills" or emergency contraceptive pills. Of the 423 teenagers who had heard of emergency contraceptive pills, one third (32%) did not know that a prescription is necessary to obtain them, and three quarters (78%) underestimated how long after unprotected intercourse the emergency contraceptive pill regimen could be initiated. Only 9% knew that emergency contraceptive pills are effective as long as 72 hours after unprotected sex. After being told about the option of emergency contraceptive pills, two thirds (67%) of teenaged girls said that they would be likely to use emergency contraceptive pills. Among the 66% of teenaged girls who had not previously heard of emergency contraceptive pills, 64% said that they would be likely to use them. CONCLUSIONS: Emergency contraceptive pills have great potential as a tool for reducing unplanned pregnancies among teenaged girls in the United States. Few teenaged girls were aware that this option exists. Once informed, teenaged girls reported being very interested in taking emergency contraceptive pills if needed.


Assuntos
Anticoncepcionais Sintéticos Pós-Coito , Conhecimentos, Atitudes e Prática em Saúde , Gravidez na Adolescência , Adolescente , Comportamento Contraceptivo , Anticoncepcionais Sintéticos Pós-Coito/administração & dosagem , Serviços Médicos de Emergência , Feminino , Humanos , Masculino , Gravidez , Gravidez na Adolescência/estatística & dados numéricos , Fatores Socioeconômicos , Estados Unidos/epidemiologia
13.
J Agric Food Chem ; 48(12): 6284-91, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11141285

RESUMO

Chufas (Cyperus esculentus) are edible tubers that, like Chinese waterchestnut (CWC), are very crisp when raw and do not soften when cooked. The present study compares the mechanical properties of chufas with those of potato and CWC in relation to the carbohydrate and phenolic compositions of the cell walls. The cutting toughness of raw chufa was higher than that of raw CWC and potato; its value decreased on boiling, as also observed with CWC, but remained over twice that of raw potato. Chufa cell walls were rich in xylose, arabinose, glucose, uronic acid, and galactose, with minor quantities of mannose. The cell walls of the parenchyma exhibited a uniform pH-dependent autofluorescence indicating the presence of cinnamic acid derivatives. Analysis of these revealed that peeled tuber cell walls are rich in ferulic acid, whereas p-coumaric acid dominates the monomeric phenol fraction of the skin. Cell wall material from both skin and peeled tubers contains a significant amount of different diferulic acids ( approximately 20% of the wall ferulic acid), consisting mainly of the 8-O-4'-, 8-5'-, and 5-5'-dimers. These are potentially available to form thermally stable cross-links between polysaccharides within the wall and between cells. This may confer thermal stability of texture.


Assuntos
Parede Celular/química , Fenóis/análise , Células Vegetais , Carboidratos/análise , Fluorescência , Plantas/química
14.
J Agric Food Chem ; 49(9): 4364-71, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11559139

RESUMO

The crispness of fruits and vegetables is dependent, predominantly, on the maintenance of cell adhesion. There is a growing body of evidence to suggest that cell adhesion in plants is controlled at the edge of cell faces rather than across the entire cell surface. The aim of the current study has been to exploit antibody-labeling techniques in conjunction with methods that induce cell separation to explore the distribution of highly esterified and weakly esterified pectic polysaccharides on the cell surface. Potato parenchyma tissue was subjected to cooking and chemical treatments, which induced softening through cell separation. Scanning electron microscopy (SEM) revealed characteristic patterns on the surface of these separated cells, which outlined the imprint of neighboring cells. Monoclonal antibodies, JIM5 and JIM7, were used to locate weakly esterified and highly esterified pectin by silver-enhanced immunogold SEM. The edge-of-face structures labeled strongly with JIM5 but not JIM7, indicating that they contained polygalacturonic acid of low ester content. In addition, adhesion of the middle lamella to the face of the primary wall was found to differ from adhesion at the edge of each cell face. This, in conjunction with the antibody-labeling observations, complements previous transmission electron microscopy studies and is consistent with the edge-of-face regions having a specialist role in cell adhesion.


Assuntos
Adesão Celular/fisiologia , Parede Celular/ultraestrutura , Pectinas/análise , Solanum tuberosum/citologia , Anticorpos Monoclonais , Culinária , Microscopia Eletrônica de Varredura
15.
J Agric Food Chem ; 48(11): 5612-7, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11087527

RESUMO

The structure and mechanical properties of onions are important factors affecting their textural quality. The onion bulb consists of several layers of pigmented, papery scales surrounding fleshy storage scales that comprise an upper epidermis, an intermediate parenchyma tissue, and a lower epidermis. The purpose of this study was to examine the chemical composition of cell walls from the papery scales and outer fleshy scales of onion (Allium cepa L. cv. Sturon) in relation to their mechanical properties. Cell-wall material (CWM) was prepared from the component tissues and analyzed for its carbohydrate and phenolic composition. The CWMs were rich in uronic acid and glucose, with smaller quantities of arabinose, galactose, and xylose. In the fleshy scales, the lower epidermis contained relatively more galactose-rich pectic polysaccharides, whereas the upper epidermis and the papery scales contained virtually no galactose. Analysis of mechanical properties showed that the order of strength of the tissues was papery scales > fleshy scales, which were in the order lower epidermis > upper epidermis > intermediate parenchyma. The upper epidermis of fleshy scales was stronger in the vertical than the horizontal direction, and both orientations showed negligible notch sensitivity. Cyclohexane-trans-1,2-diaminetetraacetate-induced vortex-induced cell separation of the intermediate layer of fleshy scales indicated that calcium cross-linking may play an important role in cell-cell adhesion. A small but significant amount of ferulic acid was found in the walls, predominantly in the thick cuticle of the lower epidermis of fleshy scales. Alkali-labile wall-bound flavonoids were also detected.


Assuntos
Cebolas/química , Cebolas/citologia , Polissacarídeos/análise , Ácidos Carboxílicos/análise , Parede Celular/química , Monossacarídeos/análise , Fenóis/análise , Ácidos Urônicos/análise
16.
J Agric Food Chem ; 49(7): 3414-9, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11453784

RESUMO

It has been reported that caroubin, a protein mixture obtained from carob seeds, has rheological properties similar to those of gluten. Comparative studies of the effects of hydration and temperature on caroubin and gluten were carried out with the aid of NMR, FTIR, scanning electron microscopy, and differential scanning calorimetry techniques. The results show that caroubin has a more ordered structure than gluten and that hydration has little effect on its secondary structure when compared to gluten. Caroubin is more easily accessible to water than gluten, suggesting that caroubin is more hydrophilic in nature. On hydration, caroubin, like gluten, forms fibrillar structures and sheets.


Assuntos
Glutens/química , Polissacarídeos/química , Sementes/química , Varredura Diferencial de Calorimetria , Galactanos , Glutens/ultraestrutura , Espectroscopia de Ressonância Magnética , Mananas , Microscopia Eletrônica de Varredura , Gomas Vegetais , Polissacarídeos/ultraestrutura , Sementes/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Água
17.
J Agric Food Chem ; 47(3): 1174-82, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10552434

RESUMO

The objective of this work was to evaluate extrusion cooking as a means to improve the nutritional properties of Phaseolus vulgaris L. that had been stored either at 42 degrees C and 80% relative humidity for 6 weeks or for periods >1 year in cereal stores in tropical conditions. Storage under these conditions resulted in an increase in cooking time increased (7.7- and 12-fold, respectively) as a result of development of the hard-to-cook (HTC) defect. Single-screw extrusion of the milled beans was carried out at four barrel temperatures and two moisture contents. The extrudate bulk density and water solubility index decreased with increasing temperature, whereas the water absorption index increased due to the higher proportion of gelatinized starch in the extruded samples. Both fresh and HTC beans contained nutritionally significant amounts of lectins, trypsin, and alpha-amylase inhibitors, which were mostly inactivated by extrusion. Extrusion also caused a considerable redistribution of insoluble dietary fiber to soluble, although the total dietary fiber content was not affected. Changes in solubility involved pectic polysaccharides, arabinose and uronic acids being the main sugars involved. Stored beans subjected to extrusion cooking showed physical and chemical characteristics similar to those of extrudates from fresh beans.


Assuntos
Culinária , Fabaceae , Plantas Medicinais , Fibras na Dieta/análise , Conservação de Alimentos , Umidade , Monossacarídeos/análise , Valor Nutritivo , Especificidade da Espécie , Clima Tropical
18.
Lipids ; 33(10): 985-92, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9832078

RESUMO

A current model for carotenoid transport and absorption in the gut proposes an initial solubilization in the oil phase of dietary emulsions followed by incorporation of the carotenoids in mixed bile salt micelles. To assess the relevance of the first stage of this model to what is observed in vivo we have examined the transfer of carotene from carrot juice to olive oil. Increased acidity enhanced the transfer from both whole juice and carotene crystals isolated from carrot chromoplasts. The transfer was significantly slower from whole juice. By using exogenous beta-carotene and measuring its transfer to oil in the presence and absence of carrot juice we have demonstrated that the inhibition of the transfer in juice arises, at least in part, from soluble juice factors. The inhibition is relieved by a fall in pH, which leads to lowering of the electric potential at the oil/aqueous phase interface and aggregation of carrot tissue including crystalline carotene. Under conditions of low pH, oil droplets adhere to the tissue aggregates, allowing carotene to pass into the oil. Our results provide an explanation for why carotene absorption in vivo is depressed by conditions of low gastric acidity.


Assuntos
Carotenoides/química , Daucus carota/química , Óleos de Plantas/química , Bebidas , Carotenoides/análise , Cristalização , Concentração de Íons de Hidrogênio , Microscopia Eletrônica , Azeite de Oliva , Tamanho da Partícula , Solubilidade , beta Caroteno/química
19.
Int J Biol Macromol ; 11(6): 339-44, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2489102

RESUMO

Complexes of amylose, the linear starch polysaccharide, with linear alcohols having chain lengths varying from 4 to 8 carbon atoms, were prepared. Either crystalline or amorphous complexes could be formed depending on preparation conditions. Crystalline complexes gave sharp X-ray diffraction patterns, characteristic of the VH form of amylose, whereas no observable pattern was obtained from the amorphous form. Thermal dissociation of the complexes occurred at increasing temperatures with increasing alcohol chain length. Crystalline complexes dissociated at temperatures approximately 23 degrees C higher than their amorphous counterparts and the enthalpy of dissociation was also greater for the crystalline samples. Enthalpy values were independent of alcohol chain length. Differences in thermal behaviour of the two types of complex may be described in terms of the polymer crystal lattice energy and may explain the variability of reported results for complex dissociation in the literature.


Assuntos
Álcoois/química , Amilose/química , Varredura Diferencial de Calorimetria , Cristalização , Microscopia Eletrônica de Varredura , Temperatura , Difração de Raios X
20.
Res Vet Sci ; 25(3): 401-2, 1978 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-749095

RESUMO

Anaplasma marginale complement fixation test antigens were frozen as drops in liquid nitrogen using an easily constructed apparatus. Economy in the use of antigen was achieved as the frozen drops were retrieved from storage in any required volume. The potency of the antigen was unaffected by the freezing and thawing technique. The technique is useful for storing other biological reagents.


Assuntos
Anaplasma/imunologia , Antígenos de Bactérias/análise , Testes de Fixação de Complemento , Nitrogênio , Preservação Biológica/métodos , Congelamento
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