Search PubMed⌕ Search

Biomedical subjects

M E Miller

Publications and source records attributed to M E Miller.

At least 181 records · Page 10Linked to original sources

The Boston bracing system for idiopathic scoliosis. Follow-up results in 295 patients.

A total of 295 patients treated with the Boston bracing system with follow-up of at least 1 year after completion of bracing are reviewed. Pre-brace curves ranged from 20-59 degrees Cobb. Mean age at brace initiation was 13.2 years with a mean treatment time of 2.9 years and mean follow-up of 1.4 years. Mean best in-brace correction averaged 50% with correction averaging 23% at the initiation of weaning from the brace. By the time of brace discontinuance, average curve correction was 15%. At follow-up, average correction was 11%. A comparison of follow-up with pre-brace values of major curves showed that 49% were unchanged +/- 5 degree, 39% achieved final correction of 5-15 degrees, 4% achieved final correction of 15 degrees or more, 4% of patients lost 5-15 degrees, and 3% lost more than 15 degrees by the time of follow-up. Eleven percent of patients underwent surgery during the period of bracing; 1% had surgery during follow-up period. Correction and control of major curves with apexes below T8 and above L2 were best. A strong correlation between best, or initial in-brace correction, and follow-up correction was noted. Young age at the initiation of bracing and higher degrees of pre-brace curvature increased the incidence of surgery. Those curves that had corrected most at the end of bracing were most at risk for loss of correction after bracing. Partial compliance with brace wear appeared as effective as full-time wear. Boston braces without superstructure appeared to be as effective as braces with superstructure for curves with apexes below T7.

Adolescent↗

Hay-Wells syndrome.

Hay-Wells syndrome is an autosomal dominant constellation of facial clefting, ankyloblepharon filiforme adnatum (fused eyelids), and ectodermal defects. Our patient, a child who had these unusual features at birth, led us to consider possible differential diagnoses based on clinical features and review of the literature.

Cleft Lip↗

Treatment delays in the course of electroconvulsive therapy.

Electroconvulsive therapy (ECT) is often delayed because the patient develops cognitive disturbances. The authors reviewed the charts of 45 depressed patients who received ECT and found that 25 patients developed cognitive dysfunctions severe enough to cause a delay in treatment. The development of organic symptoms causing delays in treatment was positively correlated with increased age and the presence of preexisting cognitive dysfunction, and the treatment delays led to longer periods of hospitalization. The authors emphasize the need for early identification of the causes of cognitive dysfunction after ECT and for careful selection of the treatment strategy for each patient to reduce the risk of adverse effects.

Age Factors↗

Ontogeny of neutrophil chemotaxis in fetal lambs.

Ontogeny of neutrophil chemotactic response using endotoxin activated adult sheep plasma as a source of complement derived chemotactic factor was examined in fetal lambs of gestational age 120-150 days. (Gestational period in sheep is approximately 150 days.) Neutrophils from fetal lambs of gestational age 120-130 days failed to respond to this chemotactic factor whereas neutrophils from fetal lambs above 131 days of gestational age responded at levels comparable to adult values. Examination of neutrophil chemotaxis in older fetuses using a different chemotactic factor derived from mitogen stimulated adult mononuclear cells revealed a selective failure of fetal neutrophils to respond to lymphocyte-derived chemotactic factor in the presence of a normal response to complement derived chemotactic factor. Among prematurely delivered twin fetuses alterations in comparison with the first twin or age-matched controls in peripheral neutrophil count (increase) and in chemotaxis (increase or decrease) were noted in second of twins delivered greater than or equal to 20 min after the first lamb, suggesting an extreme sensitivity of neutrophil functions to a variety of influences, similar to that seen in humans.

Animals↗

Host defense deficiency in newborn nonhuman primate lungs.

We have investigated two major aspects of the pulmonary host defense mechanism--alveolar macrophage function as a "first line of bacterial defense" and induced neutrophil migration into the lung as a "back-up defense." Chemotactic and phagocytic/killing assays revealed a functional deficiency in the alveolar macrophages of newborn primates. Serial bronchoalveolar lavage investigations revealed diminished neutrophil migration into the newborn primate lung. The overall pulmonary host defense capability in newborn primates was deficient. The results of this investigation may have direct clinical relevance to the susceptibility of newborns to infections and pneumonia.

Animals↗

Sweat bromide excretion in cystic fibrosis.

Sweat reabsorption of bromide and chloride was studied in controls, obligate carriers of the cystic fibrosis gene, and individuals with cystic fibrosis. Sweat and serum ultrafiltrate concentrations of bromide and chloride were determined by an anion-exchange chromatographic method. The reabsorption of each ion was determined by the ratio of the sweat concentration to the serum ultrafiltrate concentration. Sweat bromide reabsorption paralleled chloride reabsorption in each of the groups. The mean bromide reabsorption ratio for 12 controls was 0.10 +/- 0.10 (range 0 to 0.26), for 11 obligate carriers 0.09 +/- 0.09 (range 0 to 0.24), and for 13 individuals with cystic fibrosis 0.86 +/- 0.26 (range 0.47 to 1.38). The mean chloride reabsorption ratio for the controls was 0.24 +/- 0.11 (range 0.06 to 0.45), for the obligate carriers 0.22 +/- 0.10 (range 0.10 to 0.45), and for individuals with cystic fibrosis 0.95 +/- 0.09 (range 0.76 to 1.1). Thus, there was a significant decrease in bromide reabsorption in individuals with cystic fibrosis compared with controls (P less than 0.001) and heterozygotes (P less than 0.001), which was similar for chloride. As with chloride reabsorption, no difference was found in bromide reabsorption between obligate carriers and controls, indicating that this measurement could not be used for heterozygote detection. In each of the three groups bromide reabsorption was greater than chloride reabsorption. This finding is consistent with a size-dependent anion channel in the sweat epithelial cell because bromide has a smaller hydrated radius than chloride.

Absorption↗

Reactivation of tritonated models of human polymorphonuclear leukocytes (PMNs): a computer-assisted analysis.

The orientation (chemotaxis) and locomotion (chemokinesis) of human polymorphonuclear leukocytes (PMNs) are generated by an internal movement mechanism that involves active cytoplasmic movement; they are influenced by external environmental and ionic conditions. We have studied the degree to which the orientation and movement mechanisms of PMNs are self-contained within the cell and the degree to which they are under membrane control. PMNs were partially and selectively demembranated by treatment with the non-ionic detergent, octyl-phenoxyl-polyethoxyethanol (commercially known as Triton X-100) under controlled conditions. The tritonated PMNs (referred to in the literature as models) were non-motile and non-locomotory. Addition of ATP/Mg++ with a trace amount of Ca++ to the medium was followed by reactivation of the tritonated PMN models to move again as motile cells. Although these reactivated PMN models actively locomoted, they could no longer orient to chemoattractants. Thus, the reactivation process restored the physical self-contained movement parameters but could not reestablish the orientation capacity (chemotactic responsiveness) that was characteristic of live PMNs. The demembranation process apparently destroyed the chemotactic receptors and/or eradicated the coordination function of the membrane. Videotapes of normal (control) as well as reactivated PMN movement were analyzed for movement characteristics. These characteristics were objectively analyzed with a newly designed computer-assisted micro-image-processing technique whereby the videotapes were digitized and quantified and the actual PMN movement printed out in computer-graphics and tracings (Freeman codes) for confirmation of orientation and movement arising as a result of reactivation.

Adenosine Triphosphate↗

Expression of assayable residual stem cell damage in erythroid differentiation.

In rodents, residual damage is inducible in hematopoietic stem cells by exposure to ionizing radiation or alkylating agents. This damage can be assayed in mice by transferring bone marrow into lethally irradiated syngeneic recipients and subsequently measuring the incremental increase of 5-(125I)iodo-2'-deoxyuridine incorporation in spleens. In this study, bone marrow from mice treated 3 weeks previously with Methylnitrosourea (50 mg/kg) or 450 rad was injected into recipients in order to determine possible residual effects of treatment on erythroid cell differentiation following stem cell seeding. Such effects were detected by a reduced amount of 59Fe incorporation into spleens, thus indicating transfer of residual stem cell damage to differentiating cells.

Alkylating Agents↗

Serum immunoreactive erythropoietin levels in patients with polycystic kidney disease as compared with other hemodialysis patients.

Serum erythropoietin levels were randomly collected and measured by a sensitive radioimmunoassay in a hemodialysis population. For analysis, the patients were divided into two groups: those with polycystic kidney disease and those with other kidney diseases. In 12 polycystic kidney disease patients, serum erythropoietin was 22.6 +/- 2.4 mU/ml, hematocrit 29.7 +/- 1.0%, and absolute reticulocyte count 17.0 +/- 4.1 X 10(4)/microliters. In 24 other kidney disease patients, serum erythropoietin was 12.4 +/- 0.7 mU/ml, hematocrit 21.2 +/- 0.8%, and reticulocyte count 7.5 +/- 1.5 X 10(4)/microliters. Serum erythropoietin was 18.5 +/- 0.7 mU/ml in normal controls. Polycystic kidney disease patients manifested higher hematocrit, reticulocyte counts, and serum erythropoietin levels when compared to other kidney disease patients (p less than 0.01). The data suggest (1) an inappropriately low serum erythropoietin level for the severity of anemia in uremic hemodialysis patients and (2) that greater availability of erythropoietin results in more effective erythropoiesis, even in the uremic environment.

Adolescent↗

Phagocytic and killing capacities of uterine-derived polymorphonuclear leukocytes from mares resistant and susceptible to chronic endometritis.

The host defense competence of uterine-derived polymorphonuclear leukocytes (PMN) from mares considered resistant (grade I uteri) and susceptible (grade III uteri) to chronic endometritis was evaluated for phagocytic and killing (bactericidal) capacities, using a fluorochrome assay. Peripheral blood PMN from noncategorized mares and from grade I and grade III mares were used as controls. Uterine-derived PMN from mares with grade I uteri were functionally competent for phagocytosis and killing of Candida albicans, whereas uterine-derived PMN from mares with grade III uteri had significantly less phagocytic and killing capacities (P greater than or equal to 0.0001). Results of the present study, together with data obtained from chemotactic responsiveness and deformability assays of a previous study, indicated an overall deficiency in the host defense mechanism of uterine-derived PMN from mares with grade III uteri obtained 12 hours after induced Streptococcus zooepidemicus infection. This deficiency may account for the susceptibility of mares with grade III uteri to chronic endometritis.

Animals↗

Comparison of peripheral blood and uterine-derived polymorphonuclear leukocytes from mares resistant and susceptible to chronic endometritis: chemotactic and cell elastimetry analysis.

The functional competence of peripheral blood and uterine-derived polymorphonuclear leukocytes (PMN) from 12 mares were analyzed for chemotactic responsiveness using a chemotactic chamber (filter) assay and for deformability by cell elastimetry analysis. Peripheral blood PMN obtained from control mares and from 8 mares experimentally inoculated via the uterus with 1 x 10(9) Streptococcus zooepidemicus had similar normal chemotactic responsiveness and were highly deformable before and at 12 hours after inoculation. Uterine PMN obtained 12 hours after uterine inoculation with S zooepidemicus from resistant mares were not as deformable as peripheral blood PMN, but were within normal functional limits. The chemotactic responsiveness of uterine PMN from these mares was normal. Uterine PMN obtained from mares considered susceptible to endometritis 12 hours after uterine infection did not have chemotactic responsiveness and were nondeformable. The results indicated profound differences in the functional competence of uterine PMN between mares considered resistant and susceptible to chronic endometritis.

Animals↗

Anion-exchange chromatography to determine the concentration of chloride in sweat for diagnosis of cystic fibrosis.

For the diagnosis of cystic fibrosis, we use the "Macroduct Sweat Collection System" (Wescor) to sample sweat, and anion-exchange chromatography to determine its chloride content. The chromatographic system consists of a Whatman Partisil SAX 10-microns column, an isocratic phosphate-buffered mobile phase, and ultraviolet detection at 200 nm. The sweat chloride concentrations of 10 individuals with cystic fibrosis ranged from 101 to 131 mmol/L (mean 111, SD 9 mmol/L). For 11 controls the values ranged from 13 to 54 mmol/L (mean 28, SD 11 mmol/L). We conclude that the procedure is reliable for the diagnosis of cystic fibrosis.

Adult↗

Concanavalin a capping of rhesus monkey polymorphonuclear leukocytes.

The technique of capping, a probe designed to evaluate the fluidity and functional competence of human polymorphonuclear leukocytes (PMNs), has been successfully adapted for rhesus monkey PMNs. The capping characteristics of rhesus monkey PMNs are very similar to those of human PMNs. Utilizing this capping technique as an evaluation tool and with fetal/neonatal rhesus monkey as a functional animal model, the ontogeny of movement and chemotactic characteristics of PMNs can now be studied.

Animals↗