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1.
Braz J Biol ; 84: e281235, 2024.
Article in English | MEDLINE | ID: mdl-38656077

ABSTRACT

The increase in prices of fertilizers, energy and other materials necessary for the industry triggered a global economic crisis. Reason that was investigated on the biological and chemical characteristics in relation to the yield of radish nourished with humus from plant residue. The objective was to determine the appropriate dose of humus to obtain greater yield and its relationship with the chemical and biological characteristics of the radish. It is based on applied methodology with an experimental approach; Therefore, the Completely Random Block Design model was used, which consisted of 3 blocks and 5 treatments that were T1 with 0, T2 with 4, T3 with 6, T4 with 8 and T5 with 10 t/ha of humus and They applied 15 days after sowing. The physical characteristics of the radish were evaluated and processed using analysis of variance and Duncan. Concentration of elements in leaves and stomatal density were also analyzed. It was determined that T5 stood out in total plant length with 28.95 cm, plant weight with 76.87 g, equatorial diameter with 4,404 cm and commercial yield with 20,296 t/ha. Nitrogen consumption in relation to yield with 247.44 kg/ha. Stomatal density 459 stomata/mm2 and profitability with 150% and nutrient concentration in leaves highlighted T4 with N, K, Ca, Mg, Mo and Zn. It concludes that T5 stood out with 20,296 t/ha, which differed by 26.04% in relation to the control (T1) with 15,011 t/ha. Therefore, this dose added nutrients to the soil that improved the availability for plant absorption and this influenced the concentration of nutrients in leaves such as N, P and Fe and stomatal density with 459 stomata/mm2, which had a response in good development, strengthening against environmental stress and therefore greater performance.


Subject(s)
Fertilizers , Raphanus , Raphanus/chemistry , Raphanus/growth & development , Fertilizers/analysis , Humic Substances/analysis , Plant Leaves/chemistry , Nitrogen/analysis , Nitrogen/metabolism , Biomass
2.
Rev Gastroenterol Mex (Engl Ed) ; 89(2): 265-279, 2024.
Article in English | MEDLINE | ID: mdl-38789310

ABSTRACT

Gastroesophageal reflux (GER) is a frequent normal phenomenon in children of any age. It is more common in infants, in whom the majority of episodes are short-lived and cause no other symptoms or complications, differentiating it from gastroesophageal reflux disease (GERD). The diagnosis and management of GER and GERD continue to be a challenge for the physician. Therefore, the aim of the Asociación Mexicana de Gastroenterología was to adapt international documents to facilitate their adoption by primary care physicians, with the goal of standardizing quality of care and reducing the number of diagnostic tests performed and inappropriate medication use. The ADAPTE methodology was followed, and the recommendations were approved utilizing the Delphi strategy. The executive committee carried out the review of the guidelines, position papers, and international reviews that met the a priori quality criteria and possible applicability in a local context. The recommendations were taken from those sources and adapted, after which they were approved by the working group. The consensus consists of 25 statements and their supporting information on the diagnosis and treatment of GER and GERD in infants. The adapted document is the first systematic effort to provide an adequate consensus for use in Mexico, proposing a practical approach to and management of GER and GERD for healthcare providers.


Subject(s)
Gastroesophageal Reflux , Gastroesophageal Reflux/therapy , Gastroesophageal Reflux/diagnosis , Humans , Infant , Mexico , Consensus , Delphi Technique
3.
Rev Gastroenterol Mex (Engl Ed) ; 85(4): 461-471, 2020.
Article in English, Spanish | MEDLINE | ID: mdl-32863095

ABSTRACT

There has been a recent increase in the consumption of cow's milk substitutes, specifically plant-based beverages, which have erroneously been named "plant milks". Plant-based beverages do not have a standard of identity, and so their nutritional composition can vary from one brand to another, even within the same category. The aim of the present narrative review was to produce a technical opinion to serve as a frame of reference for sustaining the recommendation of soy plant-based beverages. Nutrition and gastroenterology experts that belong to the Asociación Mexicana de Gastroenterología jointly commented on and analyzed themes on plant-based beverages, and on soy drinks in particular, including their nutritional characteristics, consumption in children, and potential growth and development alterations, as well as soy drink consumption in adults and its association with gastrointestinal alterations and other conditions. Plant-based beverages, including those made from soy, are not a replacement for breastmilk or breastmilk substitutes. Soy beverages are considered safe and can enrich the varied diet of its consumers, as long as they are considered an additional liquid portion of the diet. They can be ingested by adults and children above two years of age that present with cow's milk protein allergy or lactose intolerance.


Subject(s)
Soy Milk , Adult , Animals , Child , Diet , Guidelines as Topic , Humans , Male , Rabbits
4.
Neuroscience ; 158(2): 369-72, 2009 Jan 23.
Article in English | MEDLINE | ID: mdl-19041372

ABSTRACT

The transcription factor, DeltaFosB, accumulates in a region-specific manner in brain in response to many types of chronic stimulation due to the unusual stability of the protein. The phosphorylation of Ser27 in DeltaFosB has been shown to promote this stability in vitro. We show here that this phosphorylation reaction is also important for DeltaFosB's stability in the brain in vivo and for the unique behavioral plasticity mediated by this transcription factor.


Subject(s)
Proto-Oncogene Proteins c-fos/metabolism , Serine/metabolism , Alanine/genetics , Animals , Aspartic Acid/genetics , Brain/metabolism , Cocaine/pharmacology , Dopamine Uptake Inhibitors/pharmacology , Gene Expression Regulation/genetics , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Motor Activity/drug effects , Motor Activity/genetics , Mutation/genetics , Phosphorylation/genetics , Phosphorylation/physiology , Proto-Oncogene Proteins c-fos/genetics , Serine/genetics , Time Factors
5.
Chemosphere ; 222: 114-123, 2019 May.
Article in English | MEDLINE | ID: mdl-30703650

ABSTRACT

A methodology combining experimental design methodology, liquid chromatography, excitation emission matrixes (EEM) and bioassays has been applied to study the performance of O3 and O3/UVA-vis in the treatment of a mixture of eight phenolic pollutants. An experimental design methodology based on Doehlert matrixes was employed to determine the effect of pH (between 3 and 12), ozone dosage (02-1.0 g/h) and initial concentration of the pollutants (1-6 mg/L each). The following conclusions were obtained: a) acidic pH and low O3 dosage resulted in an inefficient process, b) increasing pH and O3 amount produced an enhancement of the reaction, and c) interaction of basic pH and high amounts of ozone decreased the efficiency of the process. The combination of O3/UVA-vis was able to enhance ozonation in those experimental regions were this reagent was less efficient, namely low pH and low ozone dosages. The application of EEM-PARAFAC showed four components, corresponding to the parent pollutants and three different groups of reaction product and its evolution with time. Bioassys indicated important detoxification (from 100% to less than 30% after 1 min of treatment with initial pollutant concentration of 6 mg/L, pH = 9 and ozone dosage of 0.8 g/h) according to the studied methods (D. magna and P. subcapitata). Also estrogenic activity and dioxin-like behavior were significantly decreased.


Subject(s)
Ozone/chemistry , Phenols/chemistry , Ultraviolet Rays , Water Pollutants, Chemical/chemistry , Biological Assay , Chromatography, Liquid , Fluorometry , Hydrogen-Ion Concentration , Methods , Phenols/toxicity , Water Pollutants, Chemical/toxicity
6.
Life Sci ; 49(8): 611-5, 1991.
Article in English | MEDLINE | ID: mdl-1865755

ABSTRACT

Urinary digoxin-like immunoreactive factor (DLIF), arginine-vasopressin (AVP) and other urinary parameters were investigated under normal conditions and after the i.p. injection of the following solutions: distilled water, isotonic and hypertonic NaCl, NaHCO3, KCl and urea, at a rate of 3 ml/100 g body weight. The measurement of digoxin-like immunoreactivity by two different radioimmunoassays showed that DLIF was stimulated by all volume loads regardless of the presence or absence of osmolar compounds. This dissociation between DLIF and urinary sodium excretion suggests that DLIF may not constitute the natriuretic hormone. Moreover, a dissociation between DLIF and AVP excretion also were found, which speaks against the hypothesis of a common mechanism of stimulation for both substances.


Subject(s)
Arginine Vasopressin/urine , Blood Proteins/urine , Digoxin , Saponins , Animals , Cardenolides , Diuresis , Male , Osmosis , Potassium/urine , Radioimmunoassay , Rats , Rats, Inbred Strains , Sodium/urine , Urea/urine , Vasopressins/urine
7.
J Chromatogr A ; 921(2): 121-33, 2001 Jul 06.
Article in English | MEDLINE | ID: mdl-11471796

ABSTRACT

The introduction of a novel analytical method must be supported by consistent information about its quantitative potentialities; this is critical for whoever considers its utilization for an specific application. Unfortunately, literature abounds in papers proposing excellent chromatographic methods of analysis that have been subjected to comparatively poor quantitative evaluation. The methodology proposed in the present work makes use of some of the performance characteristics whose measurement is recommended in validation protocols; pertinent to this stage of method development are the detection and quantitation limits, the linear range and the repeatability. All this information can be calculated from the results of a calibration with several replicates at each analyte level. Replicates enable the calculation of reproducibility at several analyte levels and the estimation of the linear range; more important, replicates are necessary to detect changes in peak area standard deviation with analyte amount. Regression of calibration data by means of unweighted least-squares (ULSR) can only be performed in those cases in which homoscedasticity has been previously verified; heteroscedastic calibration data demand regression by means of weighted least-squares (WLSR), since ULSR results in gross overestimation of prediction limits at low analyte concentration. The proposal is used for the preliminary quantitative evaluation of a method for the determination of nine biogenic amines by means of pre-column derivatization with dabsyl chloride and separation of derivatives by RPLC. Limits of detection are calculated by a regression approach and by the classical signal-to-noise ratio method (S/N approach). No significant difference was detected for the amines limits of detection estimated by WLSR and by the S/N approach; ULSR estimated limits of detection are between 7 and 78 times larger than those obtained by the other two methods, as a consequence of the heteroscedasticity of calibration data.


Subject(s)
Chromatography/methods , Calibration , Evaluation Studies as Topic , Reproducibility of Results , Sensitivity and Specificity
8.
J Agric Food Chem ; 47(5): 2120-4, 1999 May.
Article in English | MEDLINE | ID: mdl-10552506

ABSTRACT

Organic extracts from mycelium and culture broth of 21 Penicillium isolates have been tested for insecticidal, insect anti-juvenile hormone (anti-JH), and antifungal activities. Culture broth extracts were the most active, mainly against insects; nearly 25% of them have shown high entomotoxicity (100% mortality at 100 microg/cm(2)). A strong in vivo anti-JH activity against Oncopeltus fasciatus Dallas was detected in the culture broth extracts from P. brevicompactum P79 and P88 isolates. The two new natural products isolated from P79, N-(2-methyl-3-oxodec-8-enoyl)-2-pyrroline (1) and 2-hept-5-enyl-3-methyl-4-oxo-6,7,8,8a-tetrahydro-4H-pyrrolo[2,1-b]-1, 3-oxazine (2), possessed anti-JH and insecticidal activity, respectively, against O. fasciatus. Synthesized natural compound 1 has shown an ED(50) of 0.7 microg/nymph when assayed on newly molted fourth-instar nymphs of O. fasciatus. Promising biological activities have also been detected in the synthetic precursors.


Subject(s)
Fungi/drug effects , Fungicides, Industrial/isolation & purification , Insecta , Insecticides/isolation & purification , Juvenile Hormones/antagonists & inhibitors , Penicillium/chemistry , Animals , Fungicides, Industrial/pharmacology , Insecticides/pharmacology , Microbial Sensitivity Tests , Penicillium/growth & development , Plants/microbiology
10.
Lipids ; 24(5): 383-8, 1989 May.
Article in English | MEDLINE | ID: mdl-2755315

ABSTRACT

Changes in fatty acid composition, microsomal delta 9- and delta 6-desaturase activities and liver contents of cholesterol and phospholipids were studied in rats fed medium chain triglyceride-supplemented diets. Weanling rats were divided into four groups and fed for three weeks a basal diet with different 10%-fat supplements: corn oil, medium chain triglyceride-corn oil, olive oil and medium chain triglyceride-olive oil. The highest relative content of saturated fatty acids corresponded to corn oil-fed animals. Both monounsaturated fatty acid content and delta 9-desaturase activity were higher in the animals fed olive oil diets than in corn oil-fed rats. The long chain polyunsaturated fatty acids of the n-3 series were increased in the olive oil and medium chain triglyceride-olive oil-fed groups probably due to the lower linoleic/alpha-linolenic ratios found in these two diets. The cholesterol/phospholipid molar ratio was unaffected by diet and the unsaturation index was only slightly changed in the four groups. Thus, some mechanism may be operative under these conditions to maintain the homeostasis of the membrane.


Subject(s)
Acyl-CoA Dehydrogenase, Long-Chain/metabolism , Dietary Fats, Unsaturated/adverse effects , Fatty Acids/metabolism , Lipid Metabolism , Microsomes, Liver/metabolism , Triglycerides/adverse effects , Animals , Dietary Fats, Unsaturated/administration & dosage , Male , Methylation , Microsomes, Liver/enzymology , Rats , Rats, Inbred Strains , Triglycerides/administration & dosage
11.
Rev. mex. ing. bioméd ; 40(3): e201926, sep.-dic. 2019. graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1127062

ABSTRACT

Resumen En estudios previos se ha demostrado que la endotoxemia inducida por lipopolisacárido (LPS) produce un desacoplamiento cardiorrespiratorio (CRP) debido a los efectos fisiológicos de la inflamación sistémica. Adicionalmente se sabe que la oxitocina tiene efectos antiinflamatorios y propiedades cardioprotectoras; sin embargo, se desconoce si ésta modifica el acoplamiento CRP. El objetivo del presente estudio fue comparar diferentes métodos matemáticos lineales y no lineales para la detección del desacoplamiento cardiorrespiratorio entre series de tiempo cardiacas y respiratorias. Se estudiaron series de tiempo R-R obtenidas de electrocardiogramas de grupos de roedores macho a los cuales se les administró solución salina o vehículo (V); lipopolisacárido (LPS); oxitocina (O) y LPS + oxitocina (LPS+Ox). Las series R-R y respiratorias derivadas del electrocardiograma (EDR) se analizaron en conjunto para cuantificar su grado de acoplamiento a través de las técnicas de correlación cruzada; entropía muestral cruzada; entropía condicional; información mutua; e información mutua de Rényi para los cuatro grupos. Se observó que la oxitocina no parece favorecer el acoplamiento CRP durante la endotoxemia inducida por LPS. Finalmente, se encontró que la entropía muestral cruzada y la entropía condicional presentaron las mayores diferencias estadísticas para identificar el desacoplamiento CRP producido por el LPS.


Abstract Previous studies have shown that LPS-induced endotoxemia causes a cardiorespiratory (CRP) uncoupling owing to the physiological effects of systemic inflammation. Also, it is known that oxytocin has anti-inflammatory effects and cardioprotective properties; however, it is unknown whether it can modify the CRP coupling. This study aimed to compare different linear and nonlinear mathematics methods for the detection of cardiorespiratory uncoupling between cardiac and respiratory time series. The R-R time series of electrocardiograms of male rodents that were administered with saline solution (V); lipopolysaccharide (LPS); oxytocin (O) and LPS + oxytocin (LPS + Ox) were studied. We tested the R-R and respiratory series derived from the electrocardiogram (EDR) for the four groups to quantify the degree of coupling with cross-correlation; cross sample entropy; conditional entropy; mutual information; and Rényi's mutual information. We found that oxytocin does not seem to favor the CRP coupling during endotoxemia induced by LPS. Finally, we observed that the cross-sample entropy and the conditional entropy presented the highest statistical differences to identify the CRP uncoupling produced by LPS.

12.
Semergen ; 38(4): 258-61, 2012.
Article in Spanish | MEDLINE | ID: mdl-23544731

ABSTRACT

A 45 year old Filipino male, with history of Hepatitis B virus infection, was seen in his primary care clinic with a lumbar mass for the past three months. On physical examination the lower limbs showed decrease strength, chest X-rays showed bilateral thickening of the apical pleura, the Mantoux skin test was positive and a lumbar magnetic resonance imaging study showed a compression fracture of D4 vertebral body and soft-tissue abscess in L1. Microbiological examination was positive for M. tuberculosis complex, and with the diagnosis of Pott́s disease, he began treatment. With the advent of anti-tuberculosis drugs, spinal involvement of tuberculosis is rare, but it continues to have a high impact on morbidity. Treatment of vertebral involvement is based on anti-tuberculosis drugs and surgery.


Subject(s)
Lumbar Vertebrae , Tuberculosis, Spinal/diagnosis , Humans , Male , Middle Aged
13.
Rev Mex Sociol ; 52(1): 169-84, 1990.
Article in Spanish | MEDLINE | ID: mdl-12316453

ABSTRACT

PIP: The author investigates trends in international migration along the southern border of Mexico, using data on the characteristics of temporary workers who provide labor for annual coffee harvests in Soconusco. Aspects considered include mechanisms of recruitment of human resources and the volume of labor migration. Data are from a survey of migrant workers employed in the coffee harvest in 1986 and 1987.^ieng


Subject(s)
Agriculture , Emigration and Immigration , Employment , Health Workforce , Transients and Migrants , Americas , Demography , Developing Countries , Economics , Latin America , Mexico , North America , Population , Population Dynamics
14.
Int Migr ; 32(2): 269-306, 1994.
Article in English | MEDLINE | ID: mdl-12346099

ABSTRACT

PIP: The author examines migratory movements and their causes in Mexico, Central and South America, and the Caribbean. Sections are included on migration trends, theoretical approaches, and methodological tools before the 1970s; the shift in migratory patterns after the 1980s; macrosocial variables as a general background of current international flows; and migration policies.^ieng


Subject(s)
Emigration and Immigration , Methods , Public Policy , Social Change , Americas , Caribbean Region , Central America , Demography , Developing Countries , Latin America , Mexico , North America , Population , Population Dynamics , South America
15.
Perf Latinoam ; 4(6): 71-119, 1995 Jun.
Article in Spanish | MEDLINE | ID: mdl-12290740

ABSTRACT

PIP: Migration in the contemporary world is striking not only due to its magnitude but also to the impact in both the destination and the origin of the migrating populations. In Latin America, the migration pattern has been substantially modified. The main internal flows in the area's countries are not only rural-urban or rural-rural, since recently there has been urban-urban and urban-metropolitan migration, and also the reverse. This can be decisive in the pattern of emerging urbanization in the area. International migrations are not only labor flows, limited to movement between neighboring countries, but have been exceeded by drifts towards the North of the continent or even beyond. The determining factors for these migrations are increasingly complex. This has caused the development of new theoretical propositions, as well as new methods and analysis techniques in the research of specific processes. (author's)^ieng


Subject(s)
Emigration and Immigration , Population Dynamics , Transients and Migrants , Urbanization , Demography , Developing Countries , Geography , Latin America , Population , Urban Population
16.
Int J Cancer ; 33(6): 765-70, 1984 Jun 15.
Article in English | MEDLINE | ID: mdl-6735522

ABSTRACT

Growth of B16 melanoma metastatic variants with 2.5 micrograms/ml of bromodeoxyuridine (BrdU) decreases cell detachment from the substratum, as measured by resistance to release by trypsin-EDTA treatment. Using an antiserum to intact melanoma cells and metabolic labelling of melanoma metastatic variants with 3H-glucosamine and subsequent electrophoretic analysis, we are now able to show that: (1) differential solubilization and immune precipitation permit the identification of hydrophilic glycoproteins of about 140 kD and 110 kD in melanoma cells with low colonizing ability; (2) the effects of BrdU on B16 melanoma appear to be exerted differentially on cells with differing metastatic behavior, since only poorly invasive melanoma cells show a stimulating effect of BrdU on the expression of the hydrophilic 140 kD glycoproteins; (3) cells with increased lung colonizing ability reveal hydrophobic 140 and 110 kD glycoprotein species with increased susceptibility to mild protease treatment, as compared with the corresponding components from poorly invasive cells. The possible relationship of the 140-110 kD glycoproteins to B16 melanoma biological behavior and cell-substratum interactions is suggested by the fact that such components undergo significant changes in cells with differing invasive behavior and detachment properties.


Subject(s)
Bromodeoxyuridine/pharmacology , Glycoproteins/analysis , Lung Neoplasms/secondary , Melanoma/pathology , Neoplasm Proteins/analysis , Animals , Cell Aggregation , Cell Line , Culture Media , Electrophoresis, Polyacrylamide Gel , Lung Neoplasms/pathology , Melanoma/analysis , Mice , Mice, Inbred C57BL , Molecular Weight , Precipitin Tests
17.
Experientia ; 48(8): 755-8, 1992 Aug 15.
Article in English | MEDLINE | ID: mdl-1387618

ABSTRACT

The effects of methimazole, an antithyroid drug, on blood pressure and other parameters were evaluated in the established phase of Goldblatt two-kidney one clip (G2K-1C) hypertension. Methimazole was administered via drinking water for five weeks, starting five weeks after hypertension had been induced. After this period of treatment, similarly high blood pressures were observed in methimazole-treated and non-treated G2K-1 C rats, despite the fact that a hypothyroid state had been achieved in methimazole-treated rats. Methimazole-treated G2K-1 C rats showed reductions in heart rate, ventricular weight, ventricular/body weight ratio and mortality in comparison with rats not treated with methimazole. These results clearly demonstrate that hypothyroidism induced by methimazole: a) does not reverse G2K-1 C hypertension, but b) improves the rate of survival and c) reduces relative cardiac hypertrophy, possibly by the reduction in cardiac work observed in Goldblatt hypothyroid rats.


Subject(s)
Cardiomegaly/drug therapy , Hypertension/drug therapy , Methimazole/pharmacology , Animals , Blood Pressure/drug effects , Body Weight , Kidney/blood supply , Male , Methimazole/therapeutic use , Rats , Rats, Inbred Strains , Renin/physiology
18.
Cell Biol Int Rep ; 9(11): 977-84, 1985 Nov.
Article in English | MEDLINE | ID: mdl-4064121

ABSTRACT

B16 melanoma cells exhibited decreased adhesion to substration and the presence of cytoplasmic granules, resembling lipid inclusions, when cultured in vitro in the presence of syngenic serum from C57/BL6 mice. This constrasted with the rapid cell attachment and absence of cytoplasmic granules in cultures seeded in medium supplemented with an identical concentration of fetal bovine serum. Electrophoretic comparison of intracellular proteins revealed similar patterns in detergent-soluble and matrix-associated proteins from cells grown with bovine or mouse serum. However, a similar analysis of the conditioned media showed clear differences in methionine-rich species which migrated in the 100 kd region in cells grown with bovine serum, and as 110 kd component in cells grown with mouse serum. Our data indicate that the poor attachment to substratum and changes in cytoplasmic organization of B16 melanoma cells, is primarily associated with specific changes in secreted proteins.


Subject(s)
Melanoma/pathology , Neoplasm Proteins/metabolism , Animals , Blood , Cell Adhesion , Cell Line , Culture Media , Cytoplasm/ultrastructure , Electrophoresis, Polyacrylamide Gel , Melanoma/metabolism , Melanoma/ultrastructure , Methionine/metabolism , Mice , Microscopy, Electron , Neoplasm Proteins/isolation & purification , Sulfur Radioisotopes
19.
Educ Med Salud ; 22(1): 54-63, 1988.
Article in Spanish | MEDLINE | ID: mdl-3168887

ABSTRACT

This paper presents the reasons which justify the need to integrate teaching in-service and health care delivery in nursing, and the mechanisms to achieve efficiency in health programs. In 1976 the Autonomous University of Nuevo Leon (Universidad Autónoma de Nuevo León), as an educational and training center and as a means for scientific and humanistic endeavor to foster the development of the community it serves, began a joint experimental project with the health sector, by means of the Guadalupe Health Program and the Nursing Development Program, with the participation of the Schools of Medicine, Nursing and Dentistry. Special importance is attached to the objectives and organization of these nursing programs, the teaching in-service methodology, and the functions and responsibilities of teachers, students and support staff. The achievements of eleven years of work are reported.


Subject(s)
Education, Nursing , Inservice Training , Primary Nursing/education , Schools, Nursing , Mexico , Universities , Workforce
20.
Int J Cancer ; 41(1): 96-100, 1988 Jan 15.
Article in English | MEDLINE | ID: mdl-2961705

ABSTRACT

B16 melanoma cells attach to matrix-bound fibronectin but fail to adhere to albumin-coated surfaces supplemented with soluble fibronectin. Attachment to substratum is also decreased in the presence of an adhesion-disrupting antibody, or when cells are seeded on substrates poorly adhesive for these cells, such as collagen gels. We have now investigated some of the more general adhesion-related alterations that occur between flattened and poorly attached cells. Immune blots of octylglucoside extracts with the adhesion-disrupting IgG revealed a 140-kDa component in flattened cells, in contrast to the increased detection of a 54-kDa species in a comparable assay with rounded cells. Surface iodination also showed a decreased external exposure of a 140-kDa fibronectin binding species and an increased labelling in multiple 34-kDa protein species, in cells with decreased attachment to substratum. Analysis of 35S-methionine-labelled cell aggregates cultured on collagen gels also revealed a decrease in the 140-kDa region and a greater labelling of multiple 54-kDa components, compared to the same cells flattened on fibronectin. A change in 54- and 34-kDa species was also seen in matrix-associated components of rounded cells that failed to attach with soluble fibronectin. Since the 34-kDa species increase in poorly adherent cells is mainly detected by iodination, and the 54-kDa species increase in the same cells is partly associated with the corresponding detergent-insoluble matrices, we propose that these 2 novel proteins may relate to cell rounding, through a transmembrane modulation involving both surface membrane and cytoskeletal structures.


Subject(s)
Antigens, Neoplasm/analysis , Antigens, Surface/analysis , Fibronectins/analysis , Melanoma, Experimental/pathology , Receptors, Immunologic/analysis , Animals , Cell Adhesion , Cell Aggregation , Cell Line , Electrophoresis, Polyacrylamide Gel , Melanoma, Experimental/immunology , Mice , Molecular Weight , Receptors, Fibronectin
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