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1.
Public Health ; 157: 62-68, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29500945

RESUMEN

OBJECTIVES: Adults who smoke increase their likelihood of death from smoking-exacerbated illnesses. The presence of illnesses exacerbated by smoking can be a powerful incentive to quit smoking. However, having a smoking-exacerbated illness does not stop all patients from smoking. Understanding that smoking may be a coping mechanism for stress, this study examined the association between the experiences of adverse events in childhood with continued smoking in adulthood among individuals and a smoking-exacerbated illness. STUDY DESIGN: This retrospective observational study used 2014-2015 data from the South Carolina Behavioral Risk Factor Surveillance System survey. METHODS: We used multivariable logistic regression to examine the impact of adverse childhood experience (ACE) exposure on current smoking status. RESULTS: A total of 6321 respondents reported having a smoking-exacerbated illness. The most frequently reported categories of smoking-exacerbated illnesses were current asthma (63.9%), previous asthma (13.0%), and diabetes (12.3%). Overall, 62.4% of respondents had at least one ACE, with 20.3% of respondents having four or more ACEs. Respondents with one to three ACEs (adjusted odds ratio [aOR] 1.38; 95% confidence interval [CI] 1.37-1.40) and four or more ACEs (aOR 2.89; CI 2.86-2.92) were both significantly more likely to smoke than respondents with no ACEs, even in the presence of illnesses exacerbated by smoking. CONCLUSIONS: Results suggest that ACE exposure may influence risky health behaviors in adulthood, such as continued smoking even in the presence of illnesses that are exacerbated by smoking. Given that smoking has been found to be a coping mechanism for adversity, anti-smoking efforts might benefit from designing interventions and treatment plans that address ACE exposure.


Asunto(s)
Acontecimientos que Cambian la Vida , Fumar/efectos adversos , Fumar/epidemiología , Adaptación Psicológica , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Asma/epidemiología , Sistema de Vigilancia de Factor de Riesgo Conductual , Diabetes Mellitus/epidemiología , Femenino , Conductas de Riesgo para la Salud , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Fumar/psicología , South Carolina/epidemiología , Estrés Psicológico/psicología , Adulto Joven
2.
J Dent Res ; 100(11): 1220-1227, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34077690

RESUMEN

Dental care professionals (DCPs) are thought to be at enhanced risk of occupational exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, robust data to support this from large-scale seroepidemiological studies are lacking. We report a longitudinal seroprevalence analysis of antibodies to SARS-CoV-2 spike glycoprotein, with baseline sampling prior to large-scale practice reopening in July 2020 and follow-up postimplementation of new public health guidance on infection prevention control (IPC) and enhanced personal protective equipment (PPE). In total, 1,507 West Midlands DCPs were recruited into this study in June 2020. Baseline seroprevalence was determined using a combined IgGAM enzyme-linked immunosorbent assay and the cohort followed longitudinally for 6 mo until January/February 2021 through the second wave of the coronavirus disease 2019 pandemic in the United Kingdom and vaccination commencement. Baseline seroprevalence was 16.3%, compared to estimates in the regional population of 6% to 7%. Seropositivity was retained in over 70% of participants at 3- and 6-mo follow-up and conferred a 75% reduced risk of infection. Nonwhite ethnicity and living in areas of greater deprivation were associated with increased baseline seroprevalence. During follow-up, no polymerase chain reaction-proven infections occurred in individuals with a baseline anti-SARS-CoV-2 IgG level greater than 147.6 IU/ml with respect to the World Health Organization international standard 20-136. After vaccination, antibody responses were more rapid and of higher magnitude in those individuals who were seropositive at baseline. Natural infection with SARS-CoV-2 prior to enhanced PPE was significantly higher in DCPs than the regional population. Natural infection leads to a serological response that remains detectable in over 70% of individuals 6 mo after initial sampling and 9 mo from the peak of the first wave of the pandemic. This response is associated with protection from future infection. Even if serological responses wane, a single dose of the Pfizer-BioNTech 162b vaccine is associated with an antibody response indicative of immunological memory.


Asunto(s)
COVID-19 , Vacunas , Atención Odontológica , Humanos , SARS-CoV-2 , Estudios Seroepidemiológicos , Reino Unido/epidemiología
3.
Scand J Immunol ; 72(1): 22-30, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20591072

RESUMEN

Collectins contribute to host defence through interactions with glycoconjugates on pathogen surfaces. We have prepared recombinant trimeric neck and carbohydrate recognition domains (NCRD) of collectins, and we now show that the NCRD of bovine conglutinin and CL-46 (like that of CL-43) have greater intrinsic antiviral activity for influenza A virus (IAV) than the human SP-D NCRD (hSP-D-NCRD). The three serum collectins differ from SP-D by having insertions adjacent to amino acid 325 and substitution of hydrophobic residues for arginine 343. We previously showed that a three amino acid (RAK) insertion, as found in CL-43, increases antiviral activity and mannan-binding activity of the hSP-D-NCRD, while the substitution of valine at 343, as in conglutinin, more strongly increased these activities. Mannan-binding activity of collectins has been considered to predict for ability to bind to high mannose glycans on viruses or other pathogens. We now show, however, that combined mutants containing the RAK insertion and R343V or R343I substitutions have greatly increased mannan-binding ability, but lower IAV binding or inhibiting activity than mutants containing R343V or R343I substitutions only. These findings indicate differences in the recognition of glycan structures of mannan and IAV by the NCRD and emphasize the importance of the flanking sequences in determining the differing interactions of human SP-D and bovine serum collectins with mannose-rich glycoconjugates on IAV and other pathogens. Of interest, we show conservation of some monoclonal antibody-binding epitopes between bovine collectin NCRD and hSP-D, suggesting shared structural motifs.


Asunto(s)
Colectinas/farmacología , Virus de la Influenza A/inmunología , Gripe Humana/inmunología , Mananos/inmunología , Proteína D Asociada a Surfactante Pulmonar/farmacología , Secuencias de Aminoácidos , Línea Celular , Colectinas/genética , Colectinas/inmunología , Ensayo de Inmunoadsorción Enzimática , Pruebas de Inhibición de Hemaglutinación , Humanos , Gripe Humana/tratamiento farmacológico , Gripe Humana/virología , Proteína D Asociada a Surfactante Pulmonar/genética , Proteína D Asociada a Surfactante Pulmonar/inmunología , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/farmacología
4.
J Cell Biol ; 78(3): 701-15, 1978 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-701356

RESUMEN

A glycoprotein immunologically related to plasma cold-insoluble globulin (CIG) and fetal skin fibroblast fibronectin has been purified from second-trimester human amniotic fluid. This protein (amniotic fluid fibronectin) migrated more slowly than CIG on sodium dodecyl sulfate gel electrophoresis and showed greater polydispersity which could result, at least in part, from heterogeneity in glycosylation. Cloned human amniotic fluid epithelioid and fibroblastic cells synthesized and secreted a protein with similar properties into the culture medium. Fibronectin was shown to be associated with the pericellular and extracellular matrix of cultured amniotic fluid cells by immunofluorescence, lactoperoxidase-catalyzed iodination, and labeling with ferritin-conjugated antibodies. The kinetics of secretion of the protein were consistent with its role as a matrix protein. We anticipate that amniotic fluid fibronectin will prove to be the same protein which elsewhere in the body is incorporated into connective tissues and basement membranes. Amniotic fluid could, therefore, serve as a convenient source of in vivo synthesized fibronectin for biological and structural studies.


Asunto(s)
Líquido Amniótico/citología , Glicoproteínas/biosíntesis , Proteínas de la Membrana/biosíntesis , Células Cultivadas , Medios de Cultivo , Células Epiteliales , Fibroblastos , Cinética , Peso Molecular
5.
J Cell Biol ; 102(4): 1164-72, 1986 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3457013

RESUMEN

Osteoclasts are the principal resorptive cells of bone, yet their capacity to degrade collagen, the major organic component of bone matrix, remains unexplored. Accordingly, we have studied the bone resorptive activity of highly enriched populations of isolated chicken osteoclasts, using as substrate devitalized rat bone which had been labeled in vivo with L-[5-3H]proline or 45Ca, and bone-like matrix produced and mineralized in vitro by osteoblast-like rat osteosarcoma cells. When co-cultured with a radiolabeled substrate, osteoclast-mediated mineral mobilization reached a maximal rate within 2 h, whereas organic matrix degradation appeared more slowly, reaching maximal rate by 12-24 h. Thereafter, the rates of organic and inorganic matrix resorption were essentially linear and parallel for at least 6 d when excess substrate was available. Osteoclast-mediated degradation of bone collagen was confirmed by amino acid analysis. 39% of the solubilized tritium was recovered as trans-4-hydroxyproline, 47% as proline. 10,000 osteoclasts solubilized 70% of the total radioactivity and 65% of the [3H]-trans-4-hydroxyproline from 100 micrograms of 25-50 micron bone fragments within 5 d. Virtually all released tritium-labeled protein was of low molecular weight, 99% with Mr less than or equal to 10,000, and 65% with Mr less than or equal to 1,000. Moreover, when the 14% of resorbed [3H]proline-labeled peptides with Mr greater than or equal to 2,000 were examined for the presence of TCA and TCB, the characteristic initial products of mammalian collagenase activity, none was detected by SDS PAGE. In addition, osteoclast-conditioned medium had no collagenolytic activity, and exogenous TCA and TCB fragments were not degraded by osteoclasts. On the other hand, osteoclast lysates have collagenolytic enzyme activity in acidic but not in neutral buffer, with maximum activity at pH 4.0. These data indicate that osteoclasts have the capacity to resorb the organic phase of bone by a process localized to the osteoclast and its attachment site. This process appears to be independent of secretion of neutral collagenase and probably reflects acid protease activity.


Asunto(s)
Calcio/metabolismo , Osteoclastos/metabolismo , Prolina/metabolismo , Animales , Matriz Ósea/metabolismo , Resorción Ósea , Radioisótopos de Calcio , Línea Celular , Pollos , Colágeno/biosíntesis , Humanos , Hidroxiprolina/metabolismo , Cinética , Osteoclastos/citología , Osteosarcoma/metabolismo , Ratas , Tritio
6.
Science ; 236(4799): 267-70, 1987 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-3563505

RESUMEN

Risk assessment is presented as a way of examining risks so that they may be better avoided, reduced, or otherwise managed. Risk implies uncertainty, so that risk assessment is largely concerned with uncertainty and hence with a concept of probability that is hard to grasp. The results of even the simplest risk assessments need to be compared with similar assessments of commonplace situations to give them some meaning. We compare and contrast some risk estimates to display their similarities and differences.


Asunto(s)
Accidentes , Epidemiología , Probabilidad , Riesgo , Carcinógenos , Humanos , Neoplasias/epidemiología , Neoplasias Inducidas por Radiación/epidemiología
7.
Science ; 237(4813): 423-6, 1987 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-3603030

RESUMEN

Abnormal accumulation of connective tissue in blood vessels contributes to alterations in vascular physiology associated with disease states such as hypertension and atherosclerosis. Elastin synthesis was studied in blood vessels from newborn calves with severe pulmonary hypertension induced by alveolar hypoxia in order to investigate the cellular stimuli that elicit changes in pulmonary arterial connective tissue production. A two- to fourfold increase in elastin production was observed in pulmonary artery tissue and medial smooth muscle cells from hypertensive calves. This stimulation of elastin production was accompanied by a corresponding increase in elastin messenger RNA consistent with regulation at the transcriptional level. Conditioned serum harvested from cultures of pulmonary artery smooth muscle cells isolated from hypertensive animals contained one or more low molecular weight elastogenic factors that stimulated the production of elastin in both fibroblasts and smooth muscle cells and altered the chemotactic responsiveness of fibroblasts to elastin peptides. These results suggest that connective tissue changes in the pulmonary vasculature in response to pulmonary hypertension are orchestrated by the medial smooth muscle cell through the generation of specific differentiation factors that alter both the secretory phenotype and responsive properties of surrounding cells.


Asunto(s)
Tejido Conectivo/fisiopatología , Hipertensión Pulmonar/fisiopatología , Músculo Liso Vascular/fisiopatología , Animales , Bovinos , Tejido Conectivo/patología , Modelos Animales de Enfermedad , Elastina/genética , Elastina/fisiología , Humanos , Hipertensión Pulmonar/patología , Hipoxia , Músculo Liso Vascular/patología , ARN Mensajero/genética , Transcripción Genética
8.
Parasitol Int ; 72: 101942, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31220634

RESUMEN

Cats are important in the epidemiology of Toxoplasma gondii infection because they are the only hosts that can excrete the environmentally resistant oocysts in the environment. Although exposure is common (approximately 30% of cats in the USA), clinical toxoplasmosis is relatively rare. Here, we report overwhelming disseminated toxoplasmosis in two litter mate 8-week-old kittens, thought to have acquired toxoplasmosis postnatally. Five domestic shorthair kittens, approximately 2-3 weeks of age, and the queen were found in upstate New York by a rescue group in spring of 2018. The kittens and queen were placed in a foster home for approximately 4-5 weeks and then transferred to a shelter. Two kittens died unexpectedly following a short illness. Postmortem examination of the two deceased kittens revealed overwhelming toxoplasmosis and the presence of entero-epithelial stages in small intestine, suggestive of recent ingestion of infected tissues. Antibodies to T. gondii were found in the deceased kittens and the queen but not in the three asymptomatic littermate kittens. No obvious cause of immunosuppression was demonstrated. Genetic typing of T. gondii from DNA extracted from liver and lungs of both kittens revealed Toxo DB #4 genotype, commonly found in wildlife. Owners and veterinarians should be aware of dangers of feeding raw meat to cats and contact with infected cat feces. Procedures to safely handle T. gondii infected feces in hospital setting are outlined.


Asunto(s)
Enfermedades de los Gatos/parasitología , Gatos/parasitología , Genotipo , Toxoplasma/genética , Toxoplasma/patogenicidad , Toxoplasmosis Animal/mortalidad , Animales , Animales Salvajes/parasitología , Heces/parasitología , Femenino , Tamaño de la Camada , Hígado/parasitología , Pulmón/parasitología , Masculino , Carne/parasitología , Embarazo , Alimentos Crudos/parasitología , Toxoplasmosis Animal/diagnóstico
9.
Br Dent J ; 234(1): 12, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36639458
10.
J Clin Invest ; 90(1): 97-106, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1634623

RESUMEN

Surfactant protein D (SP-D) is a collagenous glycoprotein that is secreted into the pulmonary airspaces by alveolar type II and nonciliated bronchiolar cells. SP-D exhibits Ca(++)-dependent carbohydrate binding in vitro and is structurally related to the collagenous C-type lectins, including serum conglutinin, serum mannose-binding proteins, and surfactant protein A. Preliminary studies showed calcium- and saccharide-dependent binding of fluorescein-conjugated or radioiodinated SP-D to a variety of microorganisms, including Gram-negative bacteria and fungi. A laboratory strain of Escherichia coli (Y1088) was chosen to further examine the mechanism(s) of binding. Binding of SP-D to Y1088 was time dependent, saturable, and inhibited by cold SP-D or competing saccharides; Scatchard analysis gave a Kd of 2 x 10(-11) M. At higher concentrations, SP-D also caused Ca(++)-dependent agglutination of Y1088 that was inhibited by alpha-glucosyl-containing saccharides, antisera to the carbohydrate-binding domain of SP-D, or Y1088 LPS. Lectin blots showed specific binding of 125I-SP-D to Y1088 LPS, as well as LPS from other several strains of enteric Gram-negative bacteria. Immunogold studies demonstrated strong and uniform surface labeling of the bacteria. Rat and human bronchoalveolar lavage (BAL) caused Ca(++)-dependent agglutination of E. coli that was dose dependent and inhibited by competing saccharides or anti-SP-D. SP-D was selectively and efficiently adsorbed from rat BAL by incubation with E. coli, and incubation of E. coli with radiolabeled rat type II cell medium revealed that SP-D is the major E. coli-binding protein secreted by freshly isolated cells in culture. We suggest that SP-D plays important roles in the lung's defense against Gram-negative bacteria.


Asunto(s)
Líquido del Lavado Bronquioalveolar/metabolismo , Glicoproteínas/metabolismo , Bacterias Gramnegativas/inmunología , Lipopolisacáridos/metabolismo , Surfactantes Pulmonares/metabolismo , Aglutinación , Escherichia coli/inmunología , Glicoproteínas/inmunología , Humanos , Lectinas/metabolismo , Proteína D Asociada a Surfactante Pulmonar , Surfactantes Pulmonares/inmunología
11.
J Clin Invest ; 89(5): 1629-35, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1569202

RESUMEN

The development of pulmonary hypertension in hypoxic newborn calves is associated with a complex pattern of increased tropoelastin and type I procollagen synthesis and deposition by smooth muscle cells in large elastic pulmonary arteries compared to normoxic controls. We examined the possibility that transforming growth factor-beta 1 (TGF-beta 1) may be associated with the production of extracellular matrix protein in this model of pulmonary hypertension. Medial smooth muscle cells in both normotensive and hypertensive vessels, as assessed by immunohistochemistry, were the major source of TGF-beta 1. Staining was confined to foci of smooth muscle cells in the outer media and appeared greater in normotensive than hypertensive vessels. Consistent with the immunohistochemistry, a progressive, age-dependent increase in normotensive pulmonary artery TGF-beta 1 mRNA was observed after birth, whereas TGF-beta 1 mRNA remained at low, basal levels in hypertensive, remodeling pulmonary arteries. These observations suggest that local expression of TGF-beta 1 is not associated with increased extracellular matrix protein synthesis in this model of hypoxic pulmonary hypertension.


Asunto(s)
Hipertensión Pulmonar/metabolismo , Arteria Pulmonar/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Animales , Secuencia de Bases , Bovinos , Expresión Génica , Inmunohistoquímica , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos/química , Reacción en Cadena de la Polimerasa , ARN Mensajero/genética , Factor de Crecimiento Transformador beta/genética
12.
J Clin Invest ; 94(1): 311-9, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8040272

RESUMEN

We tested the hypothesis that pulmonary surfactant-associated lectins--surfactant proteins A and D (SP-A, and -D)--contribute to initial protective mechanisms against influenza A viruses (IAVs). SP-D potently inhibited hemagglutination activity of several strains of IAV as well as causing viral aggregation. SP-D enhanced neutrophil binding of IAV and neutrophil respiratory burst responses to the virus. Neutrophil dysfunction resulting from IAV exposure was diminished when the virus was pre-incubated with SP-D. Each of these effects was mediated by the calcium-dependent carbohydrate-binding property of SP-D. Native SP-D preparations of both human and rat origin, as well as recombinant rat SP-D, had similar activity. SP-A also inhibited IAV hemagglutination activity. We have previously reported that related mammalian serum lectins (mannose-binding lectin [MBL] and conglutinin) have similar effects. SP-D was at least 10-fold more potent at causing hemagglutination inhibition than were SP-A or MBL. SP-D was shown to contribute to potent anti-IAV activity of human bronchoalveolar lavage fluid. These results suggest that SP-D--alone, and in conjunction with SP-A and phagocytic cells--constitutes an important component of the natural immune response to IAV infection within the respiratory tract.


Asunto(s)
Glicoproteínas/farmacología , Virus de la Influenza A/efectos de los fármacos , Surfactantes Pulmonares/farmacología , Animales , Líquido del Lavado Bronquioalveolar/química , Proteínas Portadoras/farmacología , Hemaglutinación/efectos de los fármacos , Humanos , Peróxido de Hidrógeno/metabolismo , Lectinas de Unión a Manosa , N-Formilmetionina Leucil-Fenilalanina/farmacología , Neutrófilos/efectos de los fármacos , Proteína D Asociada a Surfactante Pulmonar , Ratas
13.
J Clin Invest ; 95(6): 2699-710, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7769109

RESUMEN

Pneumocystis carinii interacts with glycoproteins present in the lower respiratory tract through its mannose-rich surface antigen complex termed gpA. Surfactant protein D (SP-D) is a recently described component of the airspace lining material that possesses a calcium-dependent lectin domain capable of interacting with glycoconjugates present on microorganisms and leukocytes. Accordingly, we evaluated the extent and localization of SP-D in the lower respiratory tract during Pneumocystis pneumonia in an immunosuppressed rat model and examined its role in modulating interaction of P. carinii with macrophages. We report that SP-D is a major component of the alveolar exudates that typify P. carinii pneumonia and is present bound to the surface of P. carinii organisms in vivo. We further demonstrate that SP-D binds to P. carinii through saccharide-mediated interactions with gpA present on the surface of the organism. Lastly, we show that SP-D augments binding of P. carinii to alveolar macrophages, but does not significantly enhance macrophage phagocytosis of the organism. The interaction of SP-D with gpA represents an additional important component of the host-parasite relationship during P. carinii pneumonia.


Asunto(s)
Glicoproteínas/metabolismo , Macrófagos Alveolares/microbiología , Pneumocystis/metabolismo , Neumonía por Pneumocystis/metabolismo , Surfactantes Pulmonares/metabolismo , Animales , Antígenos Fúngicos/metabolismo , Líquido del Lavado Bronquioalveolar/química , Metabolismo de los Hidratos de Carbono , Adhesión Celular , Proteínas Fúngicas/metabolismo , Inmunohistoquímica , Glicoproteínas de Membrana/metabolismo , Fagocitosis , Unión Proteica , Proteína D Asociada a Surfactante Pulmonar , Ratas
14.
J Clin Invest ; 78(5): 1237-44, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3771795

RESUMEN

Excessive collagen deposition plays a critical role in the development of fibrosis, and early or active fibrosis may be more susceptible to therapeutic intervention than later stages of scarring. However, at present there is no simple method for assessing the collagen-synthesizing and secreting activity of fibroblasts in human tissues. Type I procollagen carboxyterminal domains are proteolytically removed during collagen secretion. Thus, antibodies to these domains should stain fibroblasts synthesizing type I collagen but not extracellular collagen fibrils which could mask the signal from the cells. We developed and characterized a monoclonal antibody (Anti-pC) specific for the carboxyterminal propeptide of type I procollagen. To determine the relationship between Anti-pC staining and collagen synthesis, we stained embryonic and adult chicken tendon. Embryonic chick tendon fibroblasts actively synthesizing type I collagen stained heavily with Anti-pC, while quiescent adult tendon fibroblasts did not stain with Anti-pC. Wounded adult tendons developed fibroblasts that stained with Anti-pC at the wound site. Thus, Anti-pC specifically visualized fibroblasts actively synthesizing collagen. Lung biopsies from patients with fibrotic lung disease were stained with Anti-pC. Interstitial and intraalveolar fibroblasts in biopsies from patients with active fibrosis stained intensely with Anti-pC, while normal human lung was unstained. The absence of staining in normal lung supports the hypothesis that fibrosis is associated with an altered collagen-synthesizing phenotype of tissue fibroblasts. Anti-pC may provide a useful clinical tool for assessing fibrogenic activity at sites of tissue injury.


Asunto(s)
Anticuerpos Monoclonales , Pulmón/patología , Procolágeno/análisis , Fibrosis Pulmonar/patología , Colágeno/biosíntesis , Diagnóstico Diferencial , Fibroblastos/citología , Humanos , Neoplasias Pulmonares/patología , Fenotipo , Fibrosis Pulmonar/diagnóstico
15.
Br Dent J ; 232(3): 131-132, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35149783
16.
Cancer Res ; 47(22): 6086-92, 1987 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-2822240

RESUMEN

Recent studies of murine tumor models and certain human tumor cell lines have provided evidence for intratumor heterogeneity in expression of extracellular matrix receptors and in the elaboration of matrix-degrading enzymes. However, little is known about possible intratumoral heterogeneity in the production of matrix macromolecules. We have, therefore, examined the biosynthesis and secretion of matrix proteins by cells derived from a polyclonal human cell line (JH-17) established from a large cell undifferentiated carcinoma of the lung. For the present studies, we focused on the production of collagens and structural glycoproteins by two phenotypically different aneuploid clones, designated C13 and C22. These clones were distinctive in their inability to grow in soft agar or to form tumors in nude mice and had identical DNA contents. Tumor cells were labeled with [3H]proline and the newly synthesized proteins accumulating in the culture medium were identified using biochemical and immunologic techniques. Clone C13 secreted at least three genetically distinct collagens, including type V procollagen (PC), type IV procollagen, and a type VIII-like collagen. By contrast, the clone C22 synthesized fibronectin, and a single bacterial collagenase-sensitive and pepsin-resistant component consistent with type I trimer. These studies emphasize the potential diversity of matrix proteins synthesized by neoplastic cells and suggest that there is intratumoral heterogeneity in matrix protein biosynthesis in vivo. These studies further suggest that tumor-derived matrix may be altered during tumor progression or cell selection in vivo.


Asunto(s)
Colágeno/biosíntesis , Matriz Extracelular/metabolismo , Fibronectinas/biosíntesis , Carcinoma de Células Pequeñas/patología , Línea Celular , Células Clonales , Colágeno/aislamiento & purificación , Fibronectinas/aislamiento & purificación , Humanos , Neoplasias Pulmonares/patología
17.
Biochim Biophys Acta ; 1408(2-3): 278-89, 1998 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-9813367

RESUMEN

Surfactant protein D (SP-D) is a member of the family of collagenous host defense lectins, designated collectins. There is increasing evidence that SP-D, like SP-A, is an important component of the innate immune response to microbial challenge, and that it may participate in other aspects of immune and inflammatory regulation within the lung. SP-D binds to glycoconjugates and/or lipid moieties expressed by a wide variety of microorganisms and certain other organic particles, in vitro. Although binding may facilitate microbial clearance through aggregation or other direct effects on the organism, SP-D also has the capacity to modulate leukocyte function, and in some circumstances, to enhance their killing of microorganisms.


Asunto(s)
Glicoproteínas/inmunología , Lectinas/inmunología , Surfactantes Pulmonares/inmunología , Bacterias/inmunología , Bacterias/metabolismo , Hongos/inmunología , Hongos/metabolismo , Regulación de la Expresión Génica , Glicoconjugados/metabolismo , Glicoproteínas/química , Glicoproteínas/metabolismo , Inmunidad Innata , Lectinas/química , Lectinas/metabolismo , Modelos Moleculares , Fagocitos/inmunología , Unión Proteica , Proteína D Asociada a Surfactante Pulmonar , Surfactantes Pulmonares/química , Surfactantes Pulmonares/metabolismo , Virus/inmunología , Virus/metabolismo
18.
Biochim Biophys Acta ; 924(1): 81-6, 1987 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-3030446

RESUMEN

The alveolar epithelial basement membrane is believed to play important roles in lung development, in maintaining normal alveolar architecture, and in guiding repair following lung injury. However, little is known about the formation of this structure, or of the mechanisms which mediate interactions between the epithelium and specific matrix macromolecules. Since type IV collagen is a major structural component of basement membranes, we investigated the production of type IV collagen-binding proteins by primary cultures of rat lung type II pneumocytes. Cultures were labeled for up to 24 h with 3H-labeled amino acids or [3H]mannose. Soluble collagen-binding proteins which accumulated in the culture medium were isolated by chromatography on collagen-Sepharose and examined by SDS-polyacrylamide gel electrophoresis. The major type IV collagen-binding protein (CBP1) was identified as fibronectin. We also identified a novel disulfide-bonded collagen-binding glycoprotein (CBP2; Mr = 45,000, reduced). This protein was not recognized by polyclonal antibodies to fibronectin, and showed no detectable binding to denatured type I collagen. The protein was resolved from fibronectin and partially purified by sequential chromatography on gelatin and type IV collagen-Sepharose. We suggest that type II pneumocyte-derived collagen-binding proteins contribute to the formation of the epithelial basement membrane and/or mediate the attachment of these cells to collagenous components of the extracellular matrix.


Asunto(s)
Proteínas Portadoras/biosíntesis , Colágeno/metabolismo , Pulmón/metabolismo , Receptores de Superficie Celular/biosíntesis , Animales , Proteínas Portadoras/aislamiento & purificación , Células Cultivadas , Femenino , Pulmón/citología , Masculino , Ratas , Ratas Endogámicas , Receptores de Superficie Celular/aislamiento & purificación , Receptores de Colágeno
19.
Biochim Biophys Acta ; 1097(1): 55-61, 1991 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-1677590

RESUMEN

Enzymatically mediated crosslinks and nonenzymatic glycation were quantified in granulation tissue collagen in two models of hyperglycemia, diabetes and galactosemia, that have opposite effects on collagen solubility. The effects of castration, which alters collagen solubility, was also investigated. Collagen from both diabetic and galactosemic rats had significantly increased levels of dihydroxylysinonorleucine (DHLNL), a difunctional reducible crosslink. Galactosemic rats had significantly decreased levels of hydroxypyridinium, a trifunctional product of DHLNL and hydroxylysine, relative to control values, while diabetic rats had normal levels. Values for all other detectable crosslinks in collagen from hyperglycemic rats were indistinguishable from control values. Nonenzymatic glycation was increased in both groups of hyperglycemic rats. In diabetic rats, but not in galactosemic rats, nonenzymatic glycation was strongly correlated with DHLNL content. Castration had no effect on crosslink content of collagen from diabetic or galactosemic rats. This study demonstrates that (1) collagen crosslinking is abnormal in granulation tissue collagen in both experimental diabetes and galactosemia, (2) these changes are similar to those observed in skin collagen from insulin-dependent diabetic subjects and (3) the crosslinking abnormalities are not correlated with alterations in collagen solubility. We conclude that hyperglycemia-associated increases in immature crosslinks cannot account for altered collagen solubility, although impaired maturation of such crosslinks may be partially responsible for the lathyrogenic effect of galactosemia.


Asunto(s)
Colágeno/metabolismo , Tejido de Granulación/metabolismo , Hiperglucemia/metabolismo , Proteína-Lisina 6-Oxidasa/metabolismo , Acetatos , Ácido Acético , Análisis de Varianza , Animales , Glucemia/metabolismo , Colágeno/química , Diabetes Mellitus Experimental/metabolismo , Dipéptidos/metabolismo , Galactosemias/metabolismo , Masculino , Orquiectomía , Ratas , Ratas Endogámicas , Solubilidad
20.
Arch Gen Psychiatry ; 38(5): 519-26, 1981 May.
Artículo en Inglés | MEDLINE | ID: mdl-7235852

RESUMEN

This is a review of theoretical, empirical, and clinical research on therapeutic factors (TFs) in group psychotherapy covering the period 1955 to 1979. Therapeutic factors are processes that contribute to improvement in the patient's condition; they are different from conditions for change and from techniques. The following TFs are examined: self-disclosure, interaction, acceptance (cohesiveness), insight, catharsis, guidance, altruism, vicarious learning, instillation of hope, and an existential factor. Criteria for adequate experimental design in group research are proposed. About 40% of the works reviewed contain empirical studies; the quality of these studies is variable both conceptually and methodologically. It is difficult to assess the extent to which clinical practice has actually been influenced by this work on TFs.


Asunto(s)
Psicoterapia de Grupo/métodos , Catarsis , Procesos de Grupo , Estructura de Grupo , Humanos , Solución de Problemas , Relaciones Profesional-Paciente , Autorrevelación
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