Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
Phys Chem Chem Phys ; 18(44): 30652-30661, 2016 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-27790661

RESUMEN

We report calculated elastic tensors, axial Grüneisen parameters, and thermal stress distributions in Al2Mo3O12, ZrMgMo3O12, Sc2Mo3O12, and Y2Mo3O12, a series of isomorphic materials for which the coefficients of thermal expansion range from low-positive to negative. Thermal stress in polycrystalline materials arises from interactions between thermal expansion and mechanical properties, and both can be highly anisotropic. Thermal expansion anisotropy was found to be correlated with elastic anisotropy: axes with negative thermal expansion were less compliant. Calculations of axial Grüneisen parameters revealed that the thermal expansion anisotropy in these materials is in part due to the Poisson effect. Models of thermal stress due to thermal expansion anisotropy in polycrystals following cooling showed thermal stresses of sufficient magnitude to cause microcracking in all cases. The thermal expansion anisotropy was found to couple to elastic anisotropy, decreasing the bulk coefficient of thermal expansion and leading to lognormal extremes of the thermal stress distributions.

2.
J Dent Res ; 89(5): 473-7, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20139337

RESUMEN

Our previous research suggests an association between a low number of teeth and increased risk of dementia. The aim of the present study was to determine if a low number of teeth is specifically related to memory decline as evidenced by low Delayed Word Recall scores. In addition, we examined the combined effect of a low number of teeth and the apolipoprotein E epsilon4 allele on Delayed Word Recall scores. We hypothesized that the scores of those who had the allele and a low number of teeth (0-9) would decline more rapidly over time than those participants with a greater number of teeth who lacked the allele. We found that individuals with both risk factors (the allele and fewer teeth) had lower Delayed Word Recall scores at the first examination and declined more quickly compared with participants with neither of these risk factors or with either risk factor alone.


Asunto(s)
Apolipoproteína E4/análisis , Trastornos de la Memoria/clasificación , Recuerdo Mental/clasificación , Pérdida de Diente/clasificación , Factores de Edad , Anciano , Anciano de 80 o más Años , Alelos , Enfermedad de Alzheimer/genética , Apolipoproteína E4/genética , Cognición/fisiología , Demencia/clasificación , Progresión de la Enfermedad , Escolaridad , Femenino , Genotipo , Humanos , Estudios Longitudinales , Factores de Riesgo
3.
Cochrane Database Syst Rev ; (2): CD003756, 2008 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-18425893

RESUMEN

BACKGROUND: Malaria causes repeated illness in children living in endemic areas. Policies of giving antimalarial drugs at regular intervals (prophylaxis or intermittent treatment) are being considered for preschool children. OBJECTIVES: To evaluate prophylaxis and intermittent treatment with antimalarial drugs to prevent malaria in young children living in malaria-endemic areas. SEARCH STRATEGY: We searched the Cochrane Infectious Diseases Group Specialized Register (August 2007), CENTRAL (The Cochrane Library 2007, Issue 3), MEDLINE (1966 to August 2007), EMBASE (1974 to August 2007), LILACS (1982 to August 2007), mRCT (February 2007), and reference lists of identified trials. We also contacted researchers. SELECTION CRITERIA: Individually randomized and cluster-randomized controlled trials comparing antimalarial drugs given at regular intervals (prophylaxis or intermittent treatment) with placebo or no drug in children aged one month to six years or less living in a malaria-endemic area. DATA COLLECTION AND ANALYSIS: Two authors independently extracted data and assessed methodological quality. We used relative risk (RR) or weighted mean difference with 95% confidence intervals (CI) for meta-analyses. Where we detected heterogeneity and considered it appropriate to combine the trials, we used the random-effects model (REM). MAIN RESULTS: Twenty-one trials (19,394 participants), including six cluster-randomized trials, met the inclusion criteria. Prophylaxis or intermittent treatment with antimalarial drugs resulted in fewer clinical malaria episodes (RR 0.53, 95% CI 0.38 to 0.74, REM; 7037 participants, 10 trials), less severe anaemia (RR 0.70, 95% CI 0.52 to 0.94, REM; 5445 participants, 9 trials), and fewer hospital admissions for any cause (RR 0.64, 95% CI 0.49 to 0.82; 3722 participants, 5 trials). We did not detect a difference in the number of deaths from any cause (RR 0.90, 95% CI 0.65 to 1.23; 7369 participants, 10 trials), but the CI do not exclude a potentially important difference. One trial reported three serious adverse events with no statistically significant difference between study groups (1070 participants). Eight trials measured morbidity and mortality six months to two years after stopping regular antimalarial drugs; overall, there was no statistically significant difference, but participant numbers were small. AUTHORS' CONCLUSIONS: Prophylaxis and intermittent treatment with antimalarial drugs reduce clinical malaria and severe anaemia in preschool children.


Asunto(s)
Antimaláricos/administración & dosificación , Enfermedades Endémicas , Malaria/prevención & control , Anemia/epidemiología , Preescolar , Humanos , Lactante , Malaria/epidemiología , Malaria/mortalidad , Ensayos Clínicos Controlados Aleatorios como Asunto
4.
Cochrane Database Syst Rev ; (4): CD005967, 2007 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-17943870

RESUMEN

BACKGROUND: Severe malaria kills over a million people every year. We sought evidence of superiority of artesunate compared with the standard treatment quinine. OBJECTIVES: To compare artesunate with quinine for treating severe malaria. SEARCH STRATEGY: We searched the Cochrane Infectious Diseases Group Specialized Register (January 2007), CENTRAL (The Cochrane Library 2006, Issue 4), MEDLINE (1966 to January 2007), EMBASE (1974 to January 2007), LILACS (1982 to January 2007), ISI Web of Science (1945 to January 2007), the metaRegister of Controlled trials (mRCT), conference proceedings, and reference lists of articles. We contacted researchers and the World Health Organization. SELECTION CRITERIA: Randomized controlled trials comparing intravenous, intramuscular, or rectal artesunate with intravenous or intramuscular quinine for treating adults and children with severe malaria who are unable to take medication by mouth. DATA COLLECTION AND ANALYSIS: Two authors assessed the eligibility and methodological quality of trials, extracted and analysed data, and drafted the review. The third author contributed to the design and writing of the review. Death was the primary outcome. Dichotomous outcomes were summarized using relative risks and continuous outcomes by mean differences. Where appropriate, we combined data in meta-analyses. Heterogeneity was investigated for the primary outcome using subgroup analyses. MAIN RESULTS: Six trials enrolling 1938 participants (1664 adults and 274 children) met our inclusion criteria. All six trials were conducted in Asia, and only one small trial enrolled only children. Five trials used intravenous artesunate and one trial intramuscular artesunate; all six used intravenous quinine. Treatment with artesunate significantly reduced the risk of death (RR 0.62, 95% CI 0.51 to 0.75; 1938 participants, 6 trials), reduced parasite clearance time (WMD 8.14 h, 95% CI 11.55 to 4.73; 292 participants, 3 trials), and hypoglycaemia detected by routine monitoring (RR 0.46, 95% CI 0.25 to 0.87; 185 participants, 2 trials). There was no evidence of a difference in neurological sequelae, coma recovery time, time to hospital discharge, fever clearance time, or adverse effects other than hypoglycaemia. AUTHORS' CONCLUSIONS: Intravenous artesunate is the drug of choice for adults with severe malaria, particularly if acquired in Asia. This review did not identify sufficient data to make firm conclusions about the treatment of children or the effectiveness of intramuscular artesunate. There is an urgent need to compare the effects of artesunate with quinine in African children with severe malaria. The applicability of these results to Asian children and the ethics of further research are points of debate.


Asunto(s)
Antimaláricos/uso terapéutico , Artemisininas/uso terapéutico , Malaria/tratamiento farmacológico , Quinina/uso terapéutico , Sesquiterpenos/uso terapéutico , Adulto , Antimaláricos/administración & dosificación , Artemisininas/administración & dosificación , Artesunato , Niño , Humanos , Inyecciones Intramusculares , Inyecciones Intravenosas , Malaria/mortalidad , Quinina/administración & dosificación , Ensayos Clínicos Controlados Aleatorios como Asunto , Sesquiterpenos/administración & dosificación
5.
Graefes Arch Clin Exp Ophthalmol ; 243(11): 1124-33, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15952010

RESUMEN

BACKGROUND: Opacification of Hydroview posterior chamber intraocular lenses had been prescribed, but many aspects of this complication remain unknown, including its aetiology, clinical features, pathogenesis, prognosis and treatment. This paper describes an epidemic of Hydroview intraocular lens (IOL) opacification. METHODS: Subjects in whom the Hydroview IOL was implanted were recalled for evaluation of its transparency, assessment of contrast sensitivity (CS) [VCTS (Vistech CO, Dayton, Ohio, USA)] and visual acuity (LogMAR), and analysis of medical and surgical data. The results of IOL exchange in 69 eyes of 67 patients are also presented. RESULTS: Of 103 patients recalled, 46 (44.6%) and 3 (2.9%) exhibited opacification of the implanted IOL in one and both eyes, respectively. CS was significantly worse in the presence of an opacified IOL (P<0.050), even when Snellen acuity was unaffected. Where the viscoelastic employed during the primary cataract surgery was reliably documented, VISCOAT was used in 100% of cases (43/43), whereas Healonid had not been used in any (0/57) (P<0.0001). Following IOL exchange, visual acuity improved from a mean (+/-SD) of 0.75 (0.41) to 0.4 (0.34) LogMAR. CONCLUSIONS: The prevalence of Hydroview IOL opacification is associated with the use of VISCOAT in the primary cataract surgery, and there is a biochemically plausible rationale to account for this. Visual acuity and contrast sensitivity are adversely affected by opacification of the Hydroview IOL, but CS to a greater extent. Exchange of opaque IOLs is a visually rewarding procedure.


Asunto(s)
Lentes Intraoculares , Falla de Prótesis , Anciano , Anciano de 80 o más Años , Sensibilidad de Contraste/fisiología , Estudios Epidemiológicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Reoperación , Factores de Riesgo , Agudeza Visual/fisiología
6.
Clin Immunol ; 93(3): 209-21, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10600331

RESUMEN

Dendritic cells (DCs) initiate primary and stimulate secondary T-cell responses. We conducted a phase I trial of tumor necrosis factor (TNF-alpha) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in patients with cancer to increase DCs in peripheral blood or skin based on in vitro data that showed that CD34(+) hematopoietic precursors require these cytokines to mature into functional antigen-presenting DCs. Eleven patients were treated for 7 days with GM-CSF, 125 microg/m(2) twice daily as subcutaneous injections, and TNF-alpha as a continuous infusion at dose levels of 25, 50, or 100 microg/m(2)/day. The maximum tolerated dose of TNF-alpha was 50 microg/m(2)/day with this dose of GM-CSF; dose-limiting toxicities occurred in both patients treated with 100 microg/m(2)/day. One became thrombocytopenic and the other had transient confusion. Epidermal Langerhans' cells were quantitated by S100 staining of skin biopsies and DC precursors in peripheral blood by colony-forming unit dendritic (CFU-dendritic) assays. S100-positive cells in the epidermis doubled after treatment (2.55 S100(+) cells/high-power field before treatment to 6.05 after treatment, p = 0.029). CFU-dendritic in peripheral blood increased after treatment in 3 colorectal cancer patients but not in 3 patients with melanoma. CD11c(+) or CD123(+), HLA-DR(bright), lineage-negative dendritic cell precursors were not increased in peripheral blood mononuclear cells. This trial demonstrates that treatment with TNF-alpha and GM-CSF can increase the number of DCs in the skin and the number of dendritic cell precursors in the blood of some patients with cancer. This approach may increase the efficacy of vaccination to tumor antigens in cancer patients.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Células de Langerhans/efectos de los fármacos , Neoplasias/patología , Factor de Necrosis Tumoral alfa/uso terapéutico , Adulto , Biopsia , Antígeno Carcinoembrionario/sangre , Recuento de Células , Neoplasias del Colon/sangre , Ensayo de Unidades Formadoras de Colonias , Quimioterapia Combinada , Femenino , Citometría de Flujo , Humanos , Recuento de Leucocitos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/fisiología , Masculino , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Proteínas Recombinantes/uso terapéutico , Piel/patología , Trombocitopenia/inducido químicamente
7.
Blood ; 93(10): 3250-8, 1999 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-10233876

RESUMEN

This dose-escalation study was performed to evaluate the hematologic activity, biological effects, immunogenicity, and toxicity of PIXY321 (an interleukin-3/granulocyte-macrophage colony-stimulating factor fusion protein) administered after high-dose carboplatin (CBDCA) treatment. Patients with advanced cancers received CBDCA at 800 mg/m2 intravenously on day 0 of repeated 28-day cycles. In part A of the study, patients were treated with CBDCA alone during cycle 1 and then received PIXY321 on days 1 through 18 of cycle 2 and later cycles. In part B, patients received 18 days of PIXY321 beginning on day 1 of all CBDCA cycles, including cycle 1. PIXY321 was administered subcutaneously in 2 divided doses. Total doses of 135, 250, 500, 750, and 1,000 micrograms/m2/d were administered to successive cohorts of 3 to 6 patients in part A. In part B, patient groups received PIXY321 doses of 750, 1,000, and 1,250 micrograms/m2/d. The hematologic effects of PIXY321 were assessed in the first 2 cycles of therapy. Anti-PIXY321 antibody formation was assessed by enzyme-linked immunosorbent assay (ELISA) and neutralization assay. Of the 49 patients enrolled, 31 were fully evaluable for hematologic efficacy. When comparing the first B cycle (cycle B-1; with PIXY321) with the first A cycle (cycle A-1; without PIXY321), the fusion protein had no significant effect on platelet nadirs or duration of platelets less than 20,000/microL but was able to speed the time of recovery of platelet counts to 100,000/microL (15 v 20 days; P =.01). Significant improvements in neutrophil nadir and duration of ANC less than 500 were observed in cycles A-2 and B-1 (with PIXY321) as compared with cycle A-1 (without PIXY321). Initial PIXY321 prophylaxis (cycle A-2 and cycle B-1), enhanced the recovery of ANC to greater than 1,500/microL by an average of at least 8 days as compared with cycle A-1 (without PIXY321; P

Asunto(s)
Carboplatino/uso terapéutico , Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Interleucina-3/uso terapéutico , Neoplasias/tratamiento farmacológico , Adulto , Formación de Anticuerpos , Carboplatino/efectos adversos , Colesterol/sangre , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Ensayo de Inmunoadsorción Enzimática , Factor Estimulante de Colonias de Granulocitos y Macrófagos/efectos adversos , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacocinética , Humanos , Interleucina-3/efectos adversos , Interleucina-3/inmunología , Interleucina-3/farmacocinética , Recuento de Leucocitos/efectos de los fármacos , Recuento de Plaquetas/efectos de los fármacos , Proteínas Recombinantes de Fusión/efectos adversos , Proteínas Recombinantes de Fusión/farmacocinética , Proteínas Recombinantes de Fusión/uso terapéutico
8.
J Clin Oncol ; 17(3): 791-5, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10071268

RESUMEN

PURPOSE: Rituximab was recently approved for use in relapsed, low-grade non-Hodgkin's lymphoma; however, few data exist regarding the safety of this agent in patients with a high number of tumor cells in the blood. METHODS AND RESULTS: After the observation at our institution of a rapid reduction of peripheral-blood tumor cells with associated severe pulmonary infusion-related toxicity in two patients with refractory hematologic malignancies, data on three additional cases were collected from physician-submitted reports of adverse events related to rituximab treatment. Five patients with hematologic malignancies possessing a high number of blood tumor cells were treated with rituximab and developed rapid tumor clearance. The median age was 68 years (range, 26 to 78 years). Patients were diagnosed with B-cell prolymphocytic leukemia (n = 2), chronic lymphocytic leukemia (n = 2), or transformed non-Hodgkin's lymphoma (n = 1). All of these patients had bulky adenopathy or organomegaly. All five patients developed a unique syndrome of severe infusion-related reactions, thrombocytopenia, rapid decrement in circulating tumor cell load, and mild electrolyte evidence of tumor lysis, and all required hospitalization. In addition, one patient developed ascites. These events resolved, and four patients were subsequently treated with rituximab without significant complications. CONCLUSION: Rituximab administration in patients who have a high number of tumor cells in the blood may have an increased likelihood of severe initial infusion-related reactions. These data also suggest that rituximab may have activity in a variety of other lymphoid neoplasms, such as chronic lymphocytic leukemia and B-cell prolymphocytic leukemia.


Asunto(s)
Anticuerpos Monoclonales/efectos adversos , Antineoplásicos/efectos adversos , Leucemia Linfocítica Crónica de Células B/terapia , Linfoma de Células B Grandes Difuso/terapia , Células Neoplásicas Circulantes/efectos de los fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Adulto , Anciano , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales de Origen Murino , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/sangre , Linfoma de Células B Grandes Difuso/sangre , Masculino , Persona de Mediana Edad , Leucemia-Linfoma Linfoblástico de Células Precursoras B/sangre , Rituximab , Trombocitopenia/etiología
9.
J Am Dent Assoc ; 130(2): 191-9, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10036842

RESUMEN

BACKGROUND: Mercury, or Hg, is a neurotoxin that has been speculated to play a role in the pathogenesis of Alzheimer's disease, or AD. Dental amalgam releases low levels of Hg vapor and is a potential source of Hg for a large segment of the adult population. METHODS: The authors studied 68 subjects with AD and 33 control subjects without AD to determine Hg levels in multiple brain regions at autopsy and to ascertain the subjects' dental amalgam status and history. The subjects were from central Kentucky and Elm Grove, Wis. The authors conducted dental amalgam assessments during the lives of the majority of subjects and in some subjects at the time of autopsy only. The authors also determined three dental amalgam index scores--Event (placement, repair or removal of amalgam), Location and Time In Mouth--in addition to the numbers of and surface area of occlusal amalgam restorations. The authors determined Hg levels in multiple brain regions and performed full neuropathologic evaluations to confirm the normal status of the brain or the presence of AD. RESULTS: The authors found no significant association of AD with the number, surface area or history of having dental amalgam restorations. They also found no statistically significant differences in brain Hg level between subjects with AD and control subjects. CONCLUSIONS: Hg in dental amalgam restorations does not appear to be a neurotoxic factor in the pathogenesis of AD. The authors found that brain Hg levels are not associated with dental amalgam, either from existing amalgam restorations or according to subjects' dental amalgam restoration history. CLINICAL IMPLICATIONS: Dental amalgam restorations, regardless of number, occlusal surface area or time, do not relate to brain Hg levels.


Asunto(s)
Enfermedad de Alzheimer/inducido químicamente , Química Encefálica , Amalgama Dental/toxicidad , Mercurio/análisis , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Análisis de Varianza , Estudios de Casos y Controles , Amalgama Dental/análisis , Amalgama Dental/química , Registros Odontológicos , Restauración Dental Permanente/efectos adversos , Restauración Dental Permanente/estadística & datos numéricos , Femenino , Humanos , Masculino , Mercurio/toxicidad , Análisis de Regresión , Estadísticas no Paramétricas
10.
J Infect Dis ; 178(6): 1707-12, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9815223

RESUMEN

Transmission of Chlamydia trachomatis and Neisseria gonorrhoeae among infected men and their female sex partners was examined using a design enhancing the likelihood that spread was directed from men to women. Chlamydia culture-negative specimens were examined using DNA amplification tests. Infection rates in women exposed to male sex partners with Chlamydia only were 65% (20/31) and with gonorrhea only were 73% (33/45). Infection of women by either agent was not influenced by the number of sexual exposures to or coinfection in men. There was a 98% (40/41) concordance of N. gonorrhoeae isolates among partners by auxotype and serovar. Chlamydia isolates were serotyped using ELISA and immunofluorescence testing and confirmed by nested polymerase chain reaction: 50% (6/12) of men and 57% (8/14) of women yielded mixed serovars. Sixty-four percent of pairs (9/14) were infected with identical serovars and an additional 28% shared at least one serovar. Multiple serovars of C. trachomatis, but not of N. gonorrhoeae, were common in sex partners and exchanged frequently.


Asunto(s)
Infecciones por Chlamydia/transmisión , Chlamydia trachomatis , Gonorrea/transmisión , Heterosexualidad , Enfermedades de Transmisión Sexual/microbiología , Enfermedades de Transmisión Sexual/transmisión , Uretritis/microbiología , Boston/epidemiología , Infecciones por Chlamydia/complicaciones , Chlamydia trachomatis/genética , Chlamydia trachomatis/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática , Femenino , Amplificación de Genes , Gonorrea/complicaciones , Gonorrea/epidemiología , Humanos , Masculino , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/aislamiento & purificación , Prevalencia , Uretra/microbiología , Uretritis/complicaciones , Uretritis/epidemiología
11.
Am J Obstet Gynecol ; 176(3): 580-5, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9077610

RESUMEN

OBJECTIVE: Oral contraceptive use has been associated with a lower risk of symptomatic pelvic inflammatory disease but a higher risk of chlamydial cervicitis. To explain these seemingly contradictory findings, we asked whether oral contraceptive use was more common among women with unrecognized endometritis than among women with recognized endometritis. STUDY DESIGN: A multicenter case-control study was performed. Women without signs of pelvic inflammatory disease were ascertained through contact tracing of partners with sexually transmitted diseases or through presentation with cervicitis. Women with symptomatic pelvic inflammatory disease met a set of standard clinical criteria. We compared the 43 cases without signs of pelvic inflammatory disease but with endometritis ("unrecognized endometritis") with the 111 controls with recognized pelvic inflammatory disease and endometritis ("recognized endometritis"). RESULTS: Women with unrecognized endometritis were 4.3 times (95% confidence interval 1.6 to 11.7) more likely than women with recognized endometritis to use oral contraceptives. CONCLUSION: Future studies need to fully characterize the risks and benefits of oral contraceptives in relation to sexually transmitted diseases.


Asunto(s)
Anticonceptivos Orales/efectos adversos , Endometritis/diagnóstico , Enfermedad Inflamatoria Pélvica/diagnóstico , Adulto , Estudios de Casos y Controles , Errores Diagnósticos , Endometritis/etiología , Endometrio/patología , Femenino , Humanos , Enfermedad Inflamatoria Pélvica/etiología
12.
J Oral Rehabil ; 23(12): 799-804, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8971641

RESUMEN

In 46 non-patients and 46 patients, the authors examined the presence (+) and absence (-) of canine tooth guidance (CG), i.e. dynamic dental articulation events in contrast to static dental occlusion events. During a right and a left laterotrusion of the mandible, the number of simple, mutually exclusive and exhaustive tooth guidance events (possibilities) was four. In addition, the authors examined the associations between temporomandibular joint (TMJ) sounds and canine guidance events. In non-patients, CG+ was relatively infrequent (30%), and CG- was relatively frequent (70%). In patients, CG+ was relatively infrequent (22%), and CG- was relatively frequent (78%). In both non-patients and patients, bilateral CG+ was rather infrequent (15%). In both non-patients and patients with the presence of TMJ sounds, CG+ was relatively infrequent (38%) while CG- was relatively frequent (61%). In non-patients as well as patients, no evidence was found that distal CG+ (putative lateral retrusive guidance) was associated with ipsilateral TMJ sounds (relative risk = 0%), nor that the association between mesial CG+ (putative lateral protrusive guidance) and ipsilateral TMJ sounds was beyond that of mere chance (relative risk = 50%).


Asunto(s)
Diente Canino/fisiología , Oclusión Dental , Trastornos de la Articulación Temporomandibular/fisiopatología , Articulación Temporomandibular/fisiología , Articuladores Dentales , Femenino , Humanos , Registro de la Relación Maxilomandibular/instrumentación , Masculino , Mandíbula/fisiología , Prevalencia , Probabilidad , Factores de Riesgo , Sonido , Síndrome de la Disfunción de Articulación Temporomandibular/fisiopatología
13.
J Oral Rehabil ; 23(10): 686-98, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8933386

RESUMEN

In 46 non-patients and 46 patients, the authors examined the presence (+) and the absence (-) of laterotrusive (LG) and mediotrusive (MG) tooth guidance, i.e. dynamic dental articulation events in contrast to static dental occlusion events. During a right and left laterotrusion/mediotrusion of the mandible, the number of compound, mutually exclusive and exhaustive tooth guidance events (possibilities) was six. In addition, the presence and the absence of temporomandibular joint (TMJ) sounds, provoked TMJ pains, and the associations between TMJ sounds and tooth guidance events were examined. In non-patients, LG+ and MG+ was relatively infrequent (30%) while LG+ and MG- was relatively frequent (70%). In patients, LG+ and MG+ was relatively frequent (58%) while LG+ and MG- was relatively infrequent (42%). LG- and MG+ was absent in non-patients and rare in patients (3%). Either unilateral or bilateral MG+ was relatively infrequent in non-patients (30%) and relatively frequent in patients (59%). Bilateral MG+ was relatively infrequent in non-patients (20%) and relatively frequent in patients (52%). Either unilateral or bilateral TMJ sounds were relatively infrequent in non-patients (39%) and relatively frequent in patients (74%). Either unilateral or bilateral provoked TMJ pains were absent in non-patients and relatively frequent in patients (72%). The authors found no evidence that TMJ sounds were associated with the ipsilateral absence of so-called balancing contacts (MG-) in non-patients and patients. Finally, no evidence supporting the use of a so-called positive predictive value, and "extension concept' of probability theory was found.


Asunto(s)
Oclusión Dental , Análisis del Estrés Dental , Trastornos de la Articulación Temporomandibular/fisiopatología , Articulación Temporomandibular/fisiología , Adulto , Estudios de Casos y Controles , Intervalos de Confianza , Oclusión Dental Traumática/complicaciones , Oclusión Dental Traumática/fisiopatología , Femenino , Humanos , Registro de la Relación Maxilomandibular , Masculino , Oportunidad Relativa , Valor Predictivo de las Pruebas , Probabilidad , Sonido , Trastornos de la Articulación Temporomandibular/etiología
14.
J Prosthodont ; 4(4): 226-32, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8601179

RESUMEN

PURPOSE: This study focuses on the curvature and inclination of the lingual surfaces of the maxillary anterior teeth from the transition point on the cingulum to the incisal edge. MATERIALS AND METHODS: On 32 sets of mounted casts, 768 measurements were made of the curvature of the lingual surfaces utilizing radius gauges. The inclination of the lingual surface relative to the occlusal plane was recorded. The relationship of the incisal edge of the mandibular teeth to the transition point on the cingulum of the maxillary teeth was determined. Centric occlusion contact was noted on each tooth. RESULTS: Significant differences were found between the measured areas of any one tooth and between the types of teeth. The average radius ranged from 20.5 mm on the mesial ridge of the canine to 5.3 mm in the fossa of the central. The average inclination of the lingual surfaces was 46 degrees. In centric occlusion, 97% of the canines and 59% of the centrals and laterals were in contact with the opposing teeth. These contacts occurred 2.8 mm incisal to the transition point. The centrals contracted two opposing teeth (45%), and canines contacted one opposing tooth (53%). CONCLUSIONS: The function and curvature of the incisor teeth vary considerably from those of the canines. Overcontouring the lingual surfaces of the maxillary incisors to gain contact is not normal and may be detrimental.


Asunto(s)
Diente Canino/anatomía & histología , Oclusión Dental , Incisivo/anatomía & histología , Análisis de Varianza , Oclusión Dental Céntrica , Humanos , Maxilar , Odontometría/instrumentación , Valores de Referencia
15.
J Am Dent Assoc ; 126(11): 1495-501, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7499646

RESUMEN

The authors determined the number and surface area of occlusal dental amalgams in a group of 129 Roman Catholic sisters who were 75 to 102 years of age. Findings from this study of women with relatively homogeneous adult lifestyles and environments suggest that existing amalgams are not associated with lower performance on eight different tests of cognitive function.


Asunto(s)
Catolicismo , Cognición/efectos de los fármacos , Amalgama Dental/efectos adversos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Análisis de los Mínimos Cuadrados , Intoxicación por Mercurio/etiología , Pruebas Neuropsicológicas , Salud de la Mujer
16.
Am J Obstet Gynecol ; 167(3): 622-9, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1530014

RESUMEN

OBJECTIVE: We measured the seroprevalence of human immunodeficiency virus in women seeking reproductive services. STUDY DESIGN: Demographic and risk behavior data from women were linked anonymously to human immunodeficiency virus antibody results. RESULTS: The overall human immunodeficiency virus seropositivity rate of cord blood was 22 per 1000. Crude seroprevalence rates were higher for black women versus white women (25/1000 vs 22/1000) but lower for black Americans versus white Americans (21/1000 vs 29/1000). Human immunodeficiency virus infection was significantly higher for those women who acknowledge intravenous drug use (odds ratio 12.9, 95% confidence interval 7.3 to 22.7), were born in Haiti (odds ratio 2.6, 95% confidence interval 1.6 to 4.1), lacked prenatal care (odds ratio 2.2, 95% confidence interval 1.1 to 4.2), or received prenatal care at the hospital clinic versus a neighborhood health center (odds ratio 3.0, 95% confidence interval 1.7 to 5.3). The seroprevalence rates were 18/1000 for women seeking abortion and 16/1000 for women seeking family-planning services. CONCLUSION: Intravenous drug use and country of origin are major risk factors for human immunodeficiency virus infection in women, which may explain differences in seroprevalence rates in various racial or ethnic groups. Hospital-specific data on human immunodeficiency virus infection may be useful for monitoring the epidemic and allocating resources for education, counseling, testing, and prevention.


Asunto(s)
Seroprevalencia de VIH , Complicaciones Infecciosas del Embarazo , Aborto Inducido , Adulto , Boston , Servicios de Planificación Familiar , Femenino , Sangre Fetal/microbiología , Infecciones por VIH/etiología , Humanos , Trabajo de Parto , Embarazo , Grupos Raciales , Abuso de Sustancias por Vía Intravenosa/complicaciones
17.
J Oral Rehabil ; 19(2): 129-36, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1517874

RESUMEN

Surface electromyographic (EMG) recordings were obtained from the masseter muscles in healthy subjects performing brisk maximum voluntary teeth clenching (MVC) for about 1 s. During the onset (0-600 ms) of ballistic MVC activity, the peak amplitude of the EMG interference patterns showed a consistent and significant increase, on examination for 0-200 ms, 200-400 ms, and 400-600 ms of MVC activity. The peak (maximum) and median (centroid) frequencies of power spectrum density functions of the raw surface EMGs (interference patterns) showed an absence of consistent and significant changes during 0-600 ms of ballistic MVC activity. However, the estimated total energy contents (peak amplitude x peak frequency) of the surface interference patterns showed a consistent and significant increase from 0 to 600 ms of ballistic MVC activity, and this was interpreted as global recruitment/rate coding of masseteric motor units.


Asunto(s)
Electromiografía , Músculo Masetero/inervación , Neuronas Motoras/fisiología , Reclutamiento Neurofisiológico/fisiología , Adulto , Análisis de Varianza , Femenino , Análisis de Fourier , Humanos , Contracción Isométrica/fisiología , Masculino , Umbral Sensorial/fisiología , Factores de Tiempo
18.
J Oral Rehabil ; 19(1): 39-47, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1583558

RESUMEN

Using laser Doppler flowmetry (LDF), the blood microcirculation of the masseter muscle was studied in one healthy male subject performing clenching and grinding of the teeth. LDF suggested that blood flow was increased during clenching, and that it did not change appreciably during grinding. In one female patient (acute pain from myofibrostic lesion in masseter muscle), LDF suggested that flow within the lesion was increased during rest (postural position). In three healthy adults, subjected to simulated traumatic occlusion of the incisors, LDF suggested an absence of consistent changes in pulpal blood flow.


Asunto(s)
Rayos Láser , Músculo Masetero/irrigación sanguínea , Adulto , Oclusión Dental Traumática/fisiopatología , Pulpa Dental/irrigación sanguínea , Electromiografía , Dolor Facial/fisiopatología , Fatiga/fisiopatología , Femenino , Fibromialgia/fisiopatología , Humanos , Hiperemia/diagnóstico , Hiperemia/fisiopatología , Contracción Isométrica/fisiología , Masculino , Contracción Muscular/fisiología , Miositis/fisiopatología , Tiempo de Reacción/fisiología , Flujo Sanguíneo Regional
19.
J Oral Rehabil ; 19(1): 71-84, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1583560

RESUMEN

The temporomandibular joints of 20 human cadaver heads were examined by means of photography (gross anatomic images) and radiography (lateral oblique transcranial images), using the angle created by a line parallel to the Frankfurt horizontal and a line coinciding with the posterior slope of the most lateral (outermost) portion of the articular tubercle. This lateral eminence angle, made visible through an attached metal wire and a straight stick pin and pertaining to the outermost (zygomatic) portion of the eminentia, was about 45 degrees on both enlarged photographs and enlarged radiographs. There were no significant differences between the photographic and radiographic lateral eminence angles on the right and left sides. A more medially placed angle, yet pertaining to the lateral - and supposedly functional (protrusion) - portion of the glenoid fossa, was about 56 degrees on the right side and 51 degrees on the left side of the radiographic images. There were significant differences between the ipsilateral radiographic lateral and medial eminence angles. A separate decision-making analysis concluded that lateral oblique transcranial radiography is an effective, reliable, and inexpensive method for detection of bony changes in the lateral portions of the temporomandibular joints.


Asunto(s)
Hueso Temporal/diagnóstico por imagen , Articulación Temporomandibular/diagnóstico por imagen , Cartílago Articular/anatomía & histología , Cartílago Articular/diagnóstico por imagen , Cefalometría , Humanos , Cóndilo Mandibular/anatomía & histología , Cóndilo Mandibular/diagnóstico por imagen , Fotograbar , Radiografía , Hueso Temporal/anatomía & histología , Articulación Temporomandibular/anatomía & histología , Pantallas Intensificadoras de Rayos X
20.
Cranio ; 10(1): 35-41; discussion 41-2, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1302650

RESUMEN

In a sample of 20 non-patients, 60% of the subjects had an absence of subjective temporomandibular joint (TMJ) complaints (noises/sounds) that agreed with objective joint vibration analyses (electrovibratography). Among the remaining 40% of subjects, only 50% of the examined joints showed agreement between subjective and objective findings. Subjects appeared to be unable to reliably detect "weak" (early) symptoms of TMJ dysfunction but were able to reliably detect "strong" (late) symptoms of TMJ dysfunction and possibly disease. As measured through active protrusion and laterotrusion of the mandible, the guidance angles of the anterior teeth could not explain the absence and presence of TMJ vibrations.


Asunto(s)
Articulación Temporomandibular/fisiología , Adulto , Femenino , Análisis de Fourier , Humanos , Masculino , Persona de Mediana Edad , Percepción , Valor Predictivo de las Pruebas , Valores de Referencia , Sonido , Articulación Temporomandibular/fisiopatología , Síndrome de la Disfunción de Articulación Temporomandibular/diagnóstico , Síndrome de la Disfunción de Articulación Temporomandibular/fisiopatología , Transductores , Vibración
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA