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1.
Mol Ecol ; 11(11): 2393-403, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12406249

RESUMEN

A number of different biogeographical studies of the Central Highlands of the United States have yielded conflicting area cladograms. We estimate the mtDNA phylogeny of populations of the slender madtom, Noturus exilis, a clear-water stream catfish. The goal is to compare population relationships to those reported in previous studies that used upland, stream-dwelling vertebrates. A region of the NADH dehydrogenase subunit 4 gene, along with adjacent tRNAs, was sequenced for population samples from 21 different Central Highlands rivers. Sequence difference among 39 haplotypes ranged from 0.1% to 4.8%. Most haplotypes were restricted to specific rivers and mapped well onto geography. Slender madtoms from different drainages contained mostly monophyletic groups of haplotypes genetically divergent from haplotypes found in other drainages, although a few haplotypes were found in well-separated drainages. The area cladogram for the slender madtom was not similar to any of the other cladograms for other species and species groups from the area. We discuss a variety of methodological and biological reasons for the discordance, and suggest that some of the discrepancies may be resolved by the sequencing of multiple genes per species. We recommend that more, and more extensive, intraspecific phylogeography studies should be conducted for species living in the Central Highlands rivers.


Asunto(s)
Evolución Biológica , Variación Genética , Genética de Población , Ictaluridae/genética , Filogenia , Animales , ADN Mitocondrial , Haplotipos , Datos de Secuencia Molecular , NADH Deshidrogenasa/genética , ARN de Transferencia/genética , Especificidad de la Especie , Estados Unidos
2.
Ophthalmology ; 108(5): 919-29, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11320023

RESUMEN

OBJECTIVE: To evaluate the outcome of transscleral suture-fixated posterior chamber intraocular lens (PCIOL) implantation in glaucoma patients when combined with a trabeculectomy. DESIGN: A retrospective study of 56 consecutive glaucoma patients with a minimum follow-up of 6 months after transscleral suture-fixated PCIOL implantation combined with trabeculectomy. SETTING: Patients were drawn from the clinical glaucoma practice of the Kresge Eye Institute, Detroit, MICHIGAN: PATIENTS: Fifty-six eyes of 56 consecutive chronic glaucoma patients who had undergone transscleral suture-fixated PCIOL implantation in combination with a trabeculectomy were included in the analysis. RESULTS: The mean follow-up time was 38.5 +/- 19.1 months. Mean intraocular pressure (IOP) was significantly reduced, from 22.9 +/- 10.9 mmHg before surgery to 16.7 +/- 6.7 mmHg at the last follow-up visit (P = 0.0005), with the mean number of medications used also significantly decreased, from 2.3 +/- 0.9 to 1.9 +/- 0.9 (P = 0.0002). Postoperative IOP control to 21 mmHg or less was achieved or maintained in 84% of patients. Visual acuity improved or remained stable within two Snellen lines of the preoperative level in 39 eyes (70%) and within three Snellen lines in 45 eyes (80%) at the last follow-up visit. Overall, 46% to 68% of the patients had both stable visual acuity and satisfactory pressure control at the last postoperative visit, depending on criteria of varying stringency. However, 19 eyes (34%) required one or more additional surgical interventions for pressure control. Patients with anterior chamber intraocular lens (ACIOL) complications, diabetes mellitus, or a preoperative IOP level of more than 21 mmHg on maximum tolerated medications were especially prone to requiring additional surgical interventions. CONCLUSIONS: We conclude that transscleral suture-fixated PCIOL implantation can be combined successfully with a trabeculectomy and can be useful in glaucoma patients in need of both visual rehabilitation and IOP control. However, patients with ACIOL complications, diabetes, or preoperative IOP of more than 21 mmHg on maximum tolerated medications were prone to requiring additional surgical interventions.


Asunto(s)
Catarata/terapia , Glaucoma/cirugía , Lentes Intraoculares , Esclerótica/cirugía , Técnicas de Sutura , Trabeculectomía , Anciano , Anciano de 80 o más Años , Catarata/complicaciones , Enfermedad Crónica , Femenino , Estudios de Seguimiento , Glaucoma/complicaciones , Humanos , Presión Intraocular , Implantación de Lentes Intraoculares/métodos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Agudeza Visual
3.
Mol Phylogenet Evol ; 18(2): 217-26, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11161757

RESUMEN

Pygmy sunfishes (Elassoma) are primarily lowland species with an interesting biogeographic dichotomy: three species have broad geographic distributions, and three are narrowly distributed (and have been recommended for threatened or endangered status). To test phylogenetic predictions derived from the geographic distributions of pygmy sunfishes and possible historical factors contributing to the threatened/endangered status of the rare species, we reconstructed trees for two mitochondrial genes and introns of three nuclear genes. The pattern and rate of nuclear and mitochondrial sequence evolution were heterogeneous within Elassoma, but relationships were generally concordant across gene trees. Elassoma is monophyletic and, as predicted by geographic distributions, E. evergladei, E. okefenokee, and E. zonatum consistently branch from deeper nodes. Phylogeographic structure in mitochondrial and nuclear genes also supports an early origin of E. zonatum. Phylogenetic analyses of the five loci support widely divergent positions for the rare species E. alabamae. Two rare species, E. boehlkei and E. okatie, are sister taxa and are related to a widespread species, E. evergladei.


Asunto(s)
Peces/clasificación , Peces/genética , Animales , ADN Mitocondrial/genética , ADN Ribosómico/genética , Evolución Molecular , Intrones , Datos de Secuencia Molecular , Filogenia
4.
Memory ; 8(5): 323-32, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11045240

RESUMEN

This study examined individuals' memory for the temporal order of autobiographical events and for the components that constitute autobiographical events. Study 1 measured performance on an across-event ordering task that involved the chronological arrangement of cards that displayed event labels. Results indicated poor ordering ability across events, but a reasonable ability to order clusters of events. Study 2 compared within-event and across-event ordering using computer-presented digital photographs. Participants were better at ordering the photographs in their own across-event trials than in their within-event trials. The results are discussed in terms of the retrieval of temporal information under within- and across-event conditions.


Asunto(s)
Cronología como Asunto , Memoria/fisiología , Adolescente , Adulto , Señales (Psicología) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fotograbar , Análisis de Regresión , Estadísticas no Paramétricas , Factores de Tiempo
5.
Mol Ecol ; 8(10): 1563-9, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10583820

RESUMEN

Two morphologically distinct forms of an undescribed madtom catfish (Noturus sp.) occur in the rivers and lakes of southeastern USA. 'Lake' broadtail madtoms are endemic to Lake Waccamaw and are probably related to nearby 'river' broadtail populations. To investigate phylogenetic relationships, we surveyed mitochondrial DNA (mtDNA) sequence variation in 'lake' and 'river' broadtails and other members of the genus Noturus. Mitochondrial rDNA data suggest a sister group relationship between broadtail madtoms and N. insignis, not N. leptacanthus as posited previously. Population-level analyses using additional mtDNA characters (NADH dehydrogenase subunit 2 (ND2) and cytochrome b (Cytb)) identified two highly divergent genetic lineages within broadtail madtoms that do not correspond to the morphological designations 'river' and 'lake'.


Asunto(s)
Bagres/clasificación , Bagres/genética , ADN Mitocondrial/genética , ADN Ribosómico/genética , Filogenia , Animales , Secuencia de Bases , Bagres/anatomía & histología , Grupo Citocromo b/genética , Evolución Molecular , Variación Genética , Datos de Secuencia Molecular , NADH Deshidrogenasa/genética , ARN Ribosómico/genética , ARN Ribosómico 16S/genética , Alineación de Secuencia , Homología de Secuencia de Ácido Nucleico , Sudeste de Estados Unidos
6.
Graefes Arch Clin Exp Ophthalmol ; 236(7): 501-6, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9672795

RESUMEN

PURPOSE: To evaluate the long-term effect of adjunctive subconjunctival 5-fluorouracil (5-FU) on the filtration outcome of primary glaucoma triple procedure (PGTP) in primary open-angle glaucoma (POAG) patients. METHODS: Seventy-four POAG patients were randomly assigned to PGTP alone (36 patients) or PGTP with adjunctive subconjunctival 5-FU (5.0 +/- 1.3 injections of 5 mg each, total of 24.8 mg) (38 patients). After surgery, the patients were examined at regular intervals for intraocular pressure (IOP), visual acuity, medical therapy requirements, and complications. Surgical success was defined as IOP < or = 20 mmHg on postoperative medication < or = 1 without additional glaucoma surgery. RESULTS: Over an average follow-up (+/- SD) of 45.3 +/- 25.0 months, both 5-FU and control groups maintained significant improvement of IOP control and visual acuity. However, there were no statistically significant differences between the 5-FU and control groups with respect to postoperative IOP, number of glaucoma medications, visual acuity outcome, and success rate overall or in selected patients with one or more of the risk factors for filtration failure. CONCLUSIONS: The use of low-dose subconjunctival 5-FU (mean dosage of 24.8 mg in 5.0 +/- 1.3 injections) as an adjunct did not significantly improve the long-term filtration outcome of PGTP in POAG patients.


Asunto(s)
Fluorouracilo/administración & dosificación , Glaucoma de Ángulo Abierto/cirugía , Implantación de Lentes Intraoculares , Facoemulsificación , Trabeculectomía , Anciano , Quimioterapia Adyuvante , Femenino , Estudios de Seguimiento , Glaucoma de Ángulo Abierto/tratamiento farmacológico , Humanos , Inyecciones , Presión Intraocular , Masculino , Estudios Prospectivos , Resultado del Tratamiento , Agudeza Visual
7.
Am J Ophthalmol ; 116(5): 594-9, 1993 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-8238220

RESUMEN

Subconjunctival 5-fluorouracil has been an effective adjunct in glaucoma filtering surgery. We investigated the effectiveness of 5-fluorouracil in primary trabeculectomy combined with phacoemulsification and posterior chamber intraocular lens implantation (glaucoma triple procedure). Seventy-four patients were enrolled and randomly assigned into two groups to receive either no 5-fluorouracil (control patients) or low-dose 5-fluorouracil (mean total dose, 24.8 mg; mean number of injections, 5.0 +/- 1.3). The mean preoperative intraocular pressure was 20.1 +/- 5.4 mm Hg for the 5-fluorouracil group and 21.0 +/- 5.2 mm Hg for the control group (P = .48, Student's unpaired t-test). The mean number of medications was 2.2 +/- 1.0 and 2.0 +/- 1.0 (P = .49, Mann Whitney U test), respectively. At all postoperative visits, there were no statistically significant differences in mean intraocular pressures between the two groups. Mean follow-up was 13.2 months for 5-fluorouracil-treated patients and 15.0 months for control patients. At the last postoperative visit, mean intraocular pressures were 15.4 +/- 3.7 mm Hg and 15.0 +/- 5.0 mm Hg, respectively (P = .45, Student's unpaired t-test). Both groups showed comparable visual outcome (20/40 or better in 31 of 38 5-fluorouracil-treated patients [82%] vs 32 of 36 control patients [89%]) and a decrease in number of medications needed, 0.7 +/- 1.0 and 0.7 +/- 0.9, respectively (P = .96, Mann Whitney U test). Thus, 5-fluorouracil administered as in our study did not seem to have any effect in primary trabeculectomy combined with phacoemulsification and posterior chamber intraocular lens implantation.


Asunto(s)
Extracción de Catarata , Fluorouracilo/administración & dosificación , Glaucoma de Ángulo Abierto/cirugía , Lentes Intraoculares , Trabeculectomía , Anciano , Enfermedad Crónica , Conjuntiva , Estudios de Seguimiento , Glaucoma de Ángulo Abierto/tratamiento farmacológico , Humanos , Inyecciones , Presión Intraocular , Pronóstico , Estudios Prospectivos , Agudeza Visual
8.
Am J Ophthalmol ; 109(1): 23-7, 1990 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-2297028

RESUMEN

We reviewed 241 patients (178 black and 63 white) who were examined and treated at the Detroit Medical Center between 1980 and 1989 for traumatic hyphema. Secondary hemorrhage occurred in 46 patients (19%) and was significantly higher in black patients (P less than .005). Thirty-one patients (67%) developing secondary hemorrhage had an initial hyphema filling less than 25% of the anterior chamber. Patients treated with aminocaproic acid had secondary hemorrhages at a rate of 11% (six patients) compared to 21% (40 patients) in patients who were not treated with aminocaproic acid. The high risk of secondary hemorrhage with potential ocular damage in patients with traumatic hyphema, especially black patients, supports the benefit of hospitalization and the administration of aminocaproic acid.


Asunto(s)
Lesiones Oculares/complicaciones , Hipema/etiología , Adolescente , Adulto , Negro o Afroamericano , Anciano , Anciano de 80 o más Años , Aminocaproatos/uso terapéutico , Niño , Preescolar , Lesiones Oculares/epidemiología , Femenino , Humanos , Hipema/tratamiento farmacológico , Hipema/epidemiología , Incidencia , Lactante , Masculino , Michigan/epidemiología , Persona de Mediana Edad , Factores de Riesgo , Factores Sexuales , Población Urbana
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