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1.
Anal Chem ; 84(14): 5925-31, 2012 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-22746165

RESUMEN

We demonstrate a novel array-based diagnostic platform comprising lipid/polydiacetylene (PDA) vesicles embedded within a transparent silica-gel matrix. The diagnostic scheme is based upon the unique chromatic properties of PDA, which undergoes blue-red transformations induced by interactions with amphiphilic or membrane-active analytes. We show that constructing a gel matrix array hosting PDA vesicles with different lipid compositions and applying to blood plasma obtained from healthy individuals and from patients suffering from disease, respectively, allow distinguishing among the disease conditions through application of a simple machine-learning algorithm, using the colorimetric response of the lipid/PDA/gel matrix as the input. Importantly, the new colorimetric diagnostic approach does not require a priori knowledge on the exact metabolite compositions of the blood plasma, since the concept relies only on identifying statistically significant changes in overall disease-induced chromatic response. The chromatic lipid/PDA/gel array-based "fingerprinting" concept is generic, easy to apply, and could be implemented for varied diagnostic and screening applications.


Asunto(s)
Esclerosis Amiotrófica Lateral/diagnóstico , Colorimetría/instrumentación , Enfermedades Inflamatorias del Intestino/diagnóstico , Lípidos/química , Polímeros/química , Poliinos/química , Gel de Sílice/química , Adulto , Anciano , Anciano de 80 o más Años , Esclerosis Amiotrófica Lateral/sangre , Cápsulas , Diagnóstico Diferencial , Femenino , Humanos , Enfermedades Inflamatorias del Intestino/sangre , Masculino , Persona de Mediana Edad , Polímero Poliacetilénico , Adulto Joven
2.
Lupus ; 21(2): 136-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22235043

RESUMEN

Morphea and other scleroderma-like skin conditions are occasionally linked with exposure to chemical compounds such as silicone. We treated a 56-year-old woman with generalized severe skin induration accompanied with systemic symptoms and peripheral eosinophilia, which appeared 2.5 years after breast silicone implantation and abdominal liposuction. Blood test results and histopathological examination of her skin suggested the diagnosis of morphea overlapping with eosinophilic fasciitis. Her skin disease was presumed to be an autoimmune reaction to silicone implantation. While the removal of the implants did not improve her illness, treatment with 1 mg/kg prednisone and PUVA bath was initiated, with some improvement. This patient illustrates an example of ASIA (Autoimmune Syndrome Induced by Adjuvants), as her disease appeared following exposure to an adjuvant stimulus, with 'typical', although not well-defined, autoimmune manifestations.


Asunto(s)
Adyuvantes Inmunológicos/efectos adversos , Enfermedades Autoinmunes/inducido químicamente , Implantes de Mama/efectos adversos , Esclerodermia Localizada/etiología , Esclerodermia Localizada/inmunología , Siliconas/efectos adversos , Enfermedades Autoinmunes/inmunología , Eosinofilia/etiología , Eosinofilia/inmunología , Eosinofilia/patología , Fascitis/etiología , Fascitis/inmunología , Fascitis/patología , Femenino , Humanos , Persona de Mediana Edad , Medio Oriente , Esclerodermia Localizada/patología
3.
Int J Oral Maxillofac Surg ; 51(8): 1093-1100, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35339332

RESUMEN

Primary stability in low-density bone is crucial for the long-term success of implants. Tapered implants have shown particularly favourable properties under such conditions. The aim of this study was to compare the primary stability of tapered titanium and novel cylindrical zirconia dental implant systems in low-density bone. Fifty implants (25 tapered, 25 cylindrical) were placed in the anterior maxillary bone of cadavers meeting the criteria of low-density bone. The maximum insertion (ITV) and removal (RTV) torque values were recorded, and the implant stability quotients (ISQ) determined. To establish the isolated influence of cancellous bone on primary stability, the implantation procedure was performed in standardized low-density polyurethane foam bone blocks (cancellous bone model) using the same procedure. The primary stability parameters of both implant types showed significant positive correlations with bone density (Hounsfield units) and cortical thickness. In the cadaver, the cylindrical zirconia implants showed a significantly higher mean ISQ when compared to the tapered titanium implants (50.58 vs 37.26; P < 0.001). Pearson analysis showed significant positive correlations between ITV and ISQ (P = 0.016) and between RTV and ISQ (P = 0.035) for the cylindrical zirconia implants; no such correlations were observed for the tapered titanium implants. Within the limitations of this study, the results indicate that cylindrical zirconia implants represent a comparable viable treatment option to tapered titanium implants in terms of primary implant stability in low-density human bone.


Asunto(s)
Implantes Dentales , Densidad Ósea , Implantación Dental Endoósea/métodos , Diseño de Prótesis Dental , Retención de Prótesis Dentales , Humanos , Titanio , Torque
4.
Arch Intern Med ; 151(1): 105-10, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1985585

RESUMEN

To determine whether aspects of clinical history, physical examination, and laboratory studies improve the diagnostic accuracy of the chest roentgenogram in the diagnosis of Pneumocystis carinii pneumonia (PCP), we followed up 302 consecutive patients with respiratory symptoms and risk factors for human immunodeficiency virus. Of the 279 patients (92%) with follow-up information available, 31 (11%) were diagnosed with PCP. Only 68% of patients with PCP had typical chest roentgenograms. Regression analysis identified four independent predictors of PCP: diffuse or perihilar infiltrates, presence of mouth lesions, lactate dehydrogenase level more than 220 U/L, and erythrocyte sedimentation rate 50 mm/h or more. Using these four predictors, patients could be stratified into low-, intermediate-, and high-risk groups for PCP. We suggest that examination of the mouth, chest roentgenogram, lactate dehydrogenase level, and erythrocyte sedimentation rate be part of the evaluation of ambulatory patients with respiratory symptoms at risk for human immunodeficiency virus.


Asunto(s)
Infecciones por VIH/complicaciones , Neumonía por Pneumocystis/diagnóstico , Adulto , Sedimentación Sanguínea , Estudios de Seguimiento , Humanos , L-Lactato Deshidrogenasa/metabolismo , Masculino , Enfermedades de la Boca/complicaciones , Neumonía por Pneumocystis/epidemiología , Neumonía por Pneumocystis/etiología , Valor Predictivo de las Pruebas , Prevalencia , Estudios Prospectivos , Análisis de Regresión , Factores de Riesgo , Sensibilidad y Especificidad
5.
AIDS ; 5(11): 1339-43, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1768382

RESUMEN

Candidiasis is the most common oral fungal infection seen in association with HIV infection. It may present in a number of clinical forms, including pseudomembranous and erythematous candidiasis. To determine whether erythematous candidiasis, like the pseudomembranous form, is predictive of the development of AIDS, we reviewed the records of 169 HIV-seropositive patients seen at clinic of the Oral AIDS Center, University of California, San Francisco who were diagnosed with pseudomembranous or erythematous (or both) forms of oral candidiasis at their first examination. Kaplan-Meier analysis showed a rapid rate of progression to AIDS (median, 25 months) and to death (median, 43.8 months) in all three groups. We conclude that erythematous candidiasis is as serious a prognostic indicator as pseudomembranous candidiasis. Because the erythematous form is more difficult to recognize and hence is underdiagnosed, efforts should be made to teach non-dental clinicians who care for HIV-infected patients to diagnose and treat this lesion.


Asunto(s)
Candidiasis Bucal/complicaciones , Infecciones por VIH/complicaciones , Infecciones Oportunistas/complicaciones , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/mortalidad , Candidiasis Bucal/clasificación , Candidiasis Bucal/diagnóstico , Humanos , Infecciones Oportunistas/diagnóstico , Pronóstico , Tasa de Supervivencia , Factores de Tiempo
6.
Artículo en Inglés | MEDLINE | ID: mdl-1560345

RESUMEN

We investigated the prevalence of HIV-associated periodontal disease in an AIDS clinic in San Francisco. Patient recruitment occurred over 6 months with 90% patient participation. In 136 patients, three forms of periodontal disease were recorded: HIV-associated gingivitis (HIV-G), HIV-associated periodontitis (HIV-P), and conventional non-HIV-associated periodontal disease. Diagnosis was based on defined clinical criteria established before the study began. For the HIV-associated diseases, two sets of diagnostic criteria were used. One consisted of clinical signs that included bleeding on probing, pocket depth, and attachment loss; and the other consisted of the same signs but did not require probing (the measurement of the depth of the gingival sulcus). Using the first set of these criteria, HIV-G was diagnosed in 42 patients [31%; 95% confidence interval (CI) 23 to 39%] and HIV-P in 5 (4%; 95% CI 1 to 7%). Using the second set, 68 patients were diagnosed with HIV-G (50%; 95% CI 42 to 58%) and 8 with HIV-P (6%; 95% CI 2 to 10%). All other categories of periodontal disease that were non-HIV-associated were diagnosed in 60 (44%) of patients. These results indicate that while the prevalence of HIV-P is low, the prevalence of HIV-G and conventional periodontal disease among HIV-infected individuals is high and should be considered in the dental care of these patients.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Gingivitis/epidemiología , Infecciones por VIH/epidemiología , Seroprevalencia de VIH , Periodontitis/epidemiología , Adulto , Centros Comunitarios de Salud , Femenino , Gingivitis/complicaciones , Infecciones por VIH/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Periodontitis/complicaciones , San Francisco/epidemiología
7.
Mech Ageing Dev ; 92(2-3): 159-74, 1996 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-9080396

RESUMEN

During the aging process the retinal pigment epithelium (RPE) accumulates autofluorescent lysosomal storage bodies (lipofuscin). Data from previous studies led to the hypothesis that at least one of the fluorescent components of RPE lipofuscin is formed by reaction of vitamin A aldehyde with phosphatidylethanolamine (PE) in the photoreceptor outer segments. Experiments were performed to test this hypothesis. All-trans retinaldehyde was incubated with isolated bovine photoreceptor outer segments and with synthetic liposomes. Liposomes were made with two different lipid compositions. One type of liposome consisted of a mixture of lipids, including phosphatidylcholine (PC), none of which contained a primary amine. The other liposome type was identical in composition accept that some of the PC was replaced with an equimolar amount of phosphatidylethanolamine (PE). After incubation of the samples, aliquots were examined with fluorescence microscopy to assess whether any lipofuscin-like fluorescence had developed. Lipids were extracted from additional aliquots of the samples and analyzed with thin layer chromatography. Photoreceptor outer segments incubated with retinaldehyde developed an intense golden yellow fluorescent emission when illuminated with 395-440 nm light. Similar fluorescence developed in the liposomes containing PE, whereas the liposomes lacking PE or any other primary amine did not develop any detectable fluorescence. The development of fluorescence in the samples in situ correlated with the appearance of an orange colored component in the lipid extracts that displayed a weak red emission upon ultraviolet light illumination. Incorporation of this component into liposomes resulted in the appearance of a golden yellow fluorescent emission. The results of these experiments suggest that retinal, generated during visual pigment bleaching can react with PE in the photoreceptor outer segments to form a fluorophore, a derivative of which subsequently accumulates in RPE lipofuscin. An RPE lipofuscin fluorophore was previously shown to be identical to a reaction product of retinal and ethanolamine. This fluorophore is probably derived from the reaction product of outer segment PE and retinal.


Asunto(s)
Lipofuscina/biosíntesis , Liposomas/metabolismo , Retinaldehído/metabolismo , Segmento Externo de la Célula en Bastón/metabolismo , Animales , Bovinos , Fluorescencia , Fosfatidiletanolaminas/metabolismo
8.
Science ; 261(5121): 533-4, 1993 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-8342011
9.
J Anim Sci ; 63(4): 1246-57, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3771403

RESUMEN

Microbial and fermentation changes in the rumen in monensin- and lasalocid-fed cattle grazing bloat-provocative alfalfa pasture were studied using genetically bloat-susceptible, ruminally-cannulated adult cattle. Monensin at .66 and .99 mg/kg body weight daily reduced the severity of legume bloat by 41 and 73%, respectively. The same doses of lasalocid reduced bloat by 25 and 12%. Comparison of ruminal contents from animals before treatment with ruminal contents from antibiotic-treated animals showed no differences in pH, ammonia, soluble N, soluble carbohydrate, ethanol-precipitable slime and anaerobic bacterial counts. Monensin treatment decreased protozoal numbers and microbial activity, as evidenced by lower gas production from in vitro fermentation of ground alfalfa hay when compared to pretreatment. Lasalocid had no effect on protozoal counts and in vitro gas production. Addition of monensin or lasalocid (12 micrograms/ml) to in vitro fermentation of chopped, fresh alfalfa reduced microbial activity as evidenced by higher soluble N, lower ammonia concentration and decreased gas production. Monensin reduced the amount of ethanol-precipitable slime and protozoal numbers. Reduction in the severity of bloat when monensin was fed appears to be due to decreased protozoal numbers, which resulted in decreased gas production. Lasalocid did not reduce legume bloat because of its minimal effect on the ruminal protozoa.


Asunto(s)
Bovinos/fisiología , Lasalocido/farmacología , Medicago sativa/metabolismo , Monensina/farmacología , Rumen/fisiología , Alimentación Animal , Animales , Metabolismo de los Hidratos de Carbono , Eructación , Eucariontes/efectos de los fármacos , Fermentación/efectos de los fármacos , Gases , Concentración de Iones de Hidrógeno , Nitrógeno/metabolismo , Poloxaleno/farmacología , Rumen/microbiología
10.
J Anim Sci ; 56(6): 1400-6, 1983 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6874619

RESUMEN

Doses of .66 to .99 mg monensin/kg body weight reduced legume bloat in cattle about 66% when compared with pretreatment bloat scores. Similar doses of lasalocid reduced legume bloat about 26%. A dose of 44 mg poloxalene/kg body weight (recommended dose for field use) reduced legume bloat 100%. Monensin or lasalocid combined with 25 or 50% of the recommended dose of poloxalene reduced bloat under that of the antibiotics alone, but did not achieve 100% reduction. The antibiotic thiopeptin provided no preventive effect on legume bloat. Lasalocid, monensin or an experimental polyether antibiotic (X-14,547 A) at a dose of 1.32 mg/kg body weight when tested on cattle bloated on high grain diets reduced bloat by 92, 64 and 25%, respectively. Lasalocid at .66 mg/kg effectively prevented bloat from developing when given to animals before the feeding of high grain diets; however, a 1.32-mg dose was required to control bloat in cattle that were already bloating before they were given lasalocid. A dose of 1.32 mg salinomycin was ineffective in controlling grain bloat.


Asunto(s)
Antibacterianos , Enfermedades de los Bovinos/prevención & control , Grano Comestible/efectos adversos , Fabaceae/efectos adversos , Furanos/uso terapéutico , Lasalocido/uso terapéutico , Monensina/uso terapéutico , Plantas Medicinales , Rumen , Gastropatías/veterinaria , Animales , Antibacterianos/uso terapéutico , Péptidos Catiónicos Antimicrobianos , Bovinos , Susceptibilidad a Enfermedades , Quimioterapia Combinada , Femenino , Indenos/uso terapéutico , Péptidos/uso terapéutico , Poloxaleno/uso terapéutico , Gastropatías/prevención & control
11.
J Commun Disord ; 10(1-2): 181-206, 1977 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-325027

RESUMEN

Various types of devices have been patented to alleviate stuttering. Some prevent certain physical actions, such as clamping of the teeth, improper movement of the tounge and improper breathing. Others strengthen or incapacitate certain muscles. The devices and their alleged action on the body are described. United States as well as foreign patents are included. No attempt has been made to evaluate said devices


Asunto(s)
Patentes como Asunto/historia , Logopedia/instrumentación , Tartamudeo/historia , Europa (Continente) , Historia del Siglo XVIII , Historia del Siglo XX , Humanos , Estados Unidos
12.
Ann Dermatol Venereol ; 105(8-9): 725-20, 1978.
Artículo en Francés | MEDLINE | ID: mdl-367249

RESUMEN

The authors successively study the oral, peri-oral, esophageal, intestinal and anal manifestations of systemic scleroderma. They point out that dental, salivary, and esophageal involvement is of great interest for diagnosis and prognosis. They particularly describe the malabsorption syndrome including anatomical and ultrastructural lesions of the smooth muscle fibers. They present an original study of arrector pili in clinically and histologically non-involved skin of patients undergoing scleroderma. Finally they state that any suspected or diagnosed scleroderma needs a digestive check-up as follows: radiologic examination of the teeth, biopsy of the minor salivary glands of the lower lip, radiologic study of esophageal motility and radioactive C 14 glycocholate test.


Asunto(s)
Enfermedades del Esófago/etiología , Enfermedades Gastrointestinales/etiología , Manifestaciones Bucales , Esclerodermia Sistémica/complicaciones , Enfermedades del Esófago/patología , Enfermedades Gastrointestinales/patología , Humanos , Síndromes de Malabsorción/etiología , Músculo Liso/patología , Esclerodermia Sistémica/diagnóstico , Esclerodermia Sistémica/patología
19.
Am J Orthod Dentofacial Orthop ; 102(3): 277-84, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1510054

RESUMEN

Edward Angle, in his classification of malocclusions, appears to have made Class I a range of abnormality, not a point of ideal occlusion. Current goals of orthodontic treatment, however, strive for the designation "Class I occlusion" to be synonymous with the point of ideal intermeshing and not a broad range. If contemporary orthodontists are to continue to use Class I as a goal, then it is appropriate that Dr. Angle's century-old classification, be modified to be more precise.


Asunto(s)
Maloclusión/clasificación , Humanos , Estándares de Referencia
20.
Am J Orthod Dentofacial Orthop ; 102(2): 173-9, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1342781

RESUMEN

The Angle method for the classification of malocclusion has been the standard in orthodontics for 100 years, but many academics and private practitioners find difficulty applying the Angle system to malocclusions in between fully Class II and fully Class III. To evaluate whether orthodontists are consistent in classifying malocclusions accordings to Angle's method, study models were selected of three patients with ideal buccal occlusions, two patients with mutilated occlusions, and five patients with varying degrees of Class II tendency. One buccal view was photographed of each study model, and a questionnaire was printed and sent to 347 orthodontists. The 77.8% response demonstrated significant interest in the subject of dental classification and significant disagreement among orthodontists in their classification response with all patients except the two obvious ideal occlusions. Respondents were given the opportunity to comment on Angle classification and their recommendations for improved classification techniques. Many of their comments are quoted.


Asunto(s)
Maloclusión/clasificación , Ortodoncia/normas , Humanos , Estándares de Referencia , Encuestas y Cuestionarios , Estados Unidos
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