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D Moore

Publications and source records attributed to D Moore.

At least 145 records · Page 8Linked to original sources
PubMed1995

Modified transnasal endoscopic Lothrop procedure as an alternative to frontal sinus obliteration.

Persistent frontal sinusitis traditionally has been treated with external procedures such as osteoplastic frontal sinus obliteration or the Lynch procedure. Currently, functional endoscopic sinus surgery can be used in most cases to remove disease from the frontal recess, the most frequent site of frontal sinus obstruction, thereby relieving the sinusitis. In some cases, however, frontal recess exploration has failed to relieve the obstruction of the frontal sinus, necessitating an osteoplastic frontal sinus obliteration. We present our experience with a transnasal modification of the Lothrop procedure. The Lothrop procedure, first described in 1914, uses a combined external and transnasal approach to resect the median frontal sinus floor, superior nasal septum, and intersinus septum to drain the frontal sinus. This procedure was largely abandoned and forgotten by modern otolaryngologists. However, with the advent of the computed tomography scan and endoscopic techniques, we sought to reassess the basic tenant of the Lothrop procedure (i.e., wide median frontal sinus drainage). An anatomic study of cadaver heads was performed to quantify the surprisingly large potential opening and to better understand the pertinent anatomy. This procedure was performed on 10 patients, with no resulting complications and no failure to maintain patency of the frontal sinus drainage throughout the follow-up period (mean, 7 months). We are encouraged by our initial favorable results and intend to use the procedure in the future as needs arise.

Adult↗
PubMed1995

Three-probe fluorescence in situ hybridization to assess chromosome X, Y, and 8 aneuploidy in sperm of 14 men from two healthy groups: evidence for a paternal age effect on sperm aneuploidy.

The method of simultaneous three-chromosome fluorescence in situ hybridization (FISH) was developed using repetitive DNA sequence probes for chromosomes 8, X and Y and applied to semen of 14 men from two healthy groups who differed in their average ages (46.8 +/- 3.1 years, n = 4 v. 28.9 +/- 5.0 years, n = 10). The frequencies of disomic sperm determined by FISH compared well with frequencies obtained using the hamster-egg technique for human-sperm cytogenetics and with the frequencies of disomic and diploid sperm reported in previous FISH studies in this laboratory. The two groups of men did not differ in their baseline frequencies of sperm disomic for chromosome 8 (approximately 6.5 per 10(4) sperm), sperm with XY8 aneuploidy (approximately 9.5 per 10(4) sperm), or sperm with autodiploidy XX88 or YY88 (approximately 2 per 10(4) sperm). However, the older group had statistically higher frequencies of sperm carrying sex chromosomal disomy than the younger group (5.1 v. 2.2 per 10(4) sperm for XX8; 5.9 v. 2.0 per 10(4) sperm for YY8; P < 0.005). A recent report from this laboratory of sex-chromosomal aneuploidy in sperm of aged mice provides inter-species corroborating evidence for this preliminary finding of a paternal age effect on sperm aneuploidy in human males.

Adult↗
PubMed1995

Glucosamine 6-phosphate deaminase in normal human erythrocytes.

In the course of an investigation of hexosamine catabolism in the human malaria parasite, Plasmodium falciparum, it became apparent that a basic understanding of the relevant enzymatic reactions in the host erythrocyte is lacking. To acquire the necessary basic knowledge, we have determined the activities of several enzymes involved in hexosamine metabolism in normal human red blood cells. In the present communication we report the results of studies of glucosamine 6-phosphate deaminase (GlcN6-P) using a newly developed sensitive radiometric assay. The mean specific activity in extracts of fresh erythrocytes assayed within 4h of collection was 14.7 nmol/h/mg protein, whereas preparations from older erythrocytes that had been stored at 4 degrees C for up to 4 weeks had a mean specific activity of 6.2 nmol/h/mg. Characterization of the deaminase by chromatofocusing gave a pI of 8.55. The enzyme was optimally active at pH 9.0 and had a Km of 41 microM. The metal chelators EDTA and EGTA were non-inhibitory; however, inhibition was observed in the presence of metal ions, especially Cu2+, Ni2+ and Zn2+. In addition, the deaminase was also inhibited by several sugar phosphates including the reaction product, fructose 6-phosphate.

Aldose-Ketose Isomerases↗
PubMed1995

Glucosamine 6-phosphate deaminase in Plasmodium falciparum.

The pathways of glucose utilization for energy production in the malaria parasite, Plasmodium falciparum, have been studied extensively. Little is known, however, about the reactions by which glucose is converted into complex carbohydrates in the parasite, and knowledge of the catabolism of these substances is likewise scanty. The present investigation was undertaken to determine whether the parasites possess a key enzyme of glucosamine catabolism, i.e. glucosamine 6-phosphate deaminase (EC 5.3.1.40), which catalyses the conversion of the sugar phosphate to fructose 6-phosphate and ammonia. Lysates of Plasmodium-infected erythrocytes had substantially higher deaminase activity than control samples from normal erythrocytes, and an even higher specific activity was observed in extracts of isolated parasites, amounting to 20-40 times that of uninfected cells. Anion exchange chromatography indicated that the parasite deaminase eluted in a retarded position when compared to the elution profile of the erythrocyte enzyme. The charge difference suggested by these findings was established more directly by chromatofocusing, which indicated pI values of 6.85 and 8.55 for the parasite and erythrocyte deaminases, respectively. Other differences were also observed, notably a greater thermolability on the part of the parasite enzyme. These results indicated that the parasites synthesize a specific deaminase that is distinct from the normal erythrocyte enzyme. Studies on synchronized parasite cultures further indicated that the parasite deaminase is developmentally regulated, because a dramatic increase in activity levels occurred during the later stages of parasite development.

Aldose-Ketose Isomerases↗
PubMed1995

Gender differences on thought disturbance measures among schizophrenic patients.

OBJECTIVE: This study examined gender differences on three measures of thought disturbance among patients with schizophrenia and the relation between thought disturbance and social competency. METHOD: Fifty-three male and 34 female patients diagnosed with schizophrenia according to the DSM-III-R criteria were assessed on measures of thought disturbance: subscales of the Scale for the Assessment of Positive Symptoms (SAPS), subscales of the Brief Psychiatric Rating Scale (BPRS), and the Ego Impairment Index. Gender differences on the three measures of thought disturbance and the relation of these measures to demographic variables and other variables, such as social competency, were examined. RESULTS: Male and female schizophrenic patients demonstrated similar degrees of thought disturbance on the pertinent subscales of the SAPS and the BPRS, but the male schizophrenic patients had scores showing greater impairment on the Ego Impairment Index. Furthermore, a relationship between thought disturbance and social competency was confirmed. CONCLUSIONS: These findings support other studies in which female patients were found to have a "milder" form of schizophrenia, generally characterized by better social functioning, than their male counterparts. The literature regarding gender-related differences in thought disturbance in schizophrenia has been unclear and complicated by design issues such as obtaining adequate samples of subjects and optimizing measurement selection. The findings of this study suggest that use of a converging-measures strategy allows a better assessment of thought disturbance in severely ill schizophrenic patients and an understanding of the importance of thought disorder with respect to gender-related patterns of clinical characteristics, such as social competency.

Adult↗
PubMed1995

Three-hour paclitaxel infusion in patients with refractory and relapsed non-Hodgkin's lymphoma.

PURPOSE: Paclitaxel (Taxol; Bristol-Myers Squibb Co, Princeton, NJ) is a novel antimicrotubule agent with anti-tumor activity against ovarian and breast carcinomas. Its activity when administered as a 3-hour intravenous infusion in patients with relapsed non-Hodgkin's lymphoma (NHL) has not been studied. PATIENTS AND METHODS: Patients with relapsed NHL were treated with a 3-hour infusion of 200 mg/m2 of Taxol every 3 weeks in an outpatient setting. All patients received premedication (dexamethasone, diphenhydramine, and cimetidine) to prevent allergic reactions. Responses were assessed after two courses of therapy, and patients who achieved at least partial remission (PR) continued to receive Taxol for a maximum of eight courses. RESULTS: Of 60 eligible patients, 54 (90%) were assessable for treatment toxicity and 53 (88%) were for treatment response (22 with primary refractory and 31 with relapsed disease). Twelve patients (23%) achieved a PR (n = 6) or complete remission (CR; n = 6) (95% confidence interval, 12% to 36%). Responses were observed in intermediate-grade (31%), low-grade (14%), and mantle-cell (17%) lymphomas. In the intermediate-grade lymphomas, there was a trend for a higher response rate in relapsed versus primary refractory disease (54% v 13%; P = .08). Treatment-related toxicity included alopecia (100%), peripheral neuropathy (37%), myalgia or arthralgia (25%), and neutropenic fever (11%). None of the patients had allergic reactions or cardiac toxicity. CONCLUSION: At this dose and schedule, Taxol is an active agent in patients with relapsed NHL and can be safely administered in an outpatient setting. Combination programs with Taxol should be investigated for treatment of NHL.

Adult↗
PubMed1995

Modified transnasal endoscopic Lothrop procedure: further considerations.

The Lothrop procedure resects the medial frontal sinus floor, superior nasal septum, and intersinus septum to create a large frontonasal communication. However, the external approach often allowed medial collapse of soft tissue and stenosis of the nasofrontal communication. We describe a modified transnasal endoscopic Lothrop procedure in which drills are used for cases in which frontal recess exploration fails to relieve obstruction of the frontal sinus. The lateral bony walls are preserved, and medial collapse does not occur. The mucosa of the posterior table and posterior nasofrontal duct is preserved, and a single common frontal opening is created. We have found this approach to be safe and reliable. Fourteen patients have undergone this procedure without complication, achieving resolution or improvement of their symptoms and maintaining wide patency of the frontonasal opening. We recognize that long-term follow-up will be required but remain encouraged with our favorable results to date.

Adult↗
PubMed1995

Human cytomegalovirus induces IL-6 and TNF alpha from macrophages and microglial cells: possible role in neurotoxicity.

Human cytomegalovirus (HCMV) can frequently infect the central nervous system (CNS) in the setting of immunosuppression such as transplantation and infection with the human immunodeficiency virus (HIV). Our laboratory previously reported that HCMV infection of human brain aggregates preferentially infected a microglial/macrophage (M/M) and caused a neuropathology that differed between strains and could occur in the absence of antigen expression. We extended these studies by infecting a human brain cell aggregate model with four low passage clinical isolates of HCMV. Two patterns of cytopathology emerged after infection; a lacy eosinophilic appearance or a glial nodular formation concomitant with a decreased aggregate size. None of the infections were positive for HCMV antigen; however, all were positive for HCMV DNA. We also infected primary macrophages and microglial cells with the same HCMV isolates. Microglial cells were more susceptible to HCMV infection resulting in a lytic infection. Production of potentially neurotoxic cytokines, IL-1, IL-6 and TNF alpha, from HCMV-infected macrophages and microglial cells were evaluated to explain brain aggregate cytopathology. Supernatants from HCMV-infected macrophages and microglial cells produced similar levels of TNF alpha (< 30 pg ml-1) but showed strain and cell source variation in the production of IL-6; microglial cultures produced > 4 fold higher levels. None of the supernatants contained IL-1. Treatment of brain aggregates with either IL-6 or TNF alpha resulted in morphologic alterations and/or a decrease in size consistent with HCMV infection or supernatant treatment.

Brain↗
PubMed1995

Altered membrane microviscosity in essential hypertension: relationship with family history of hypertension and sodium-lithium countertransport activity.

OBJECTIVE: To investigate the alterations in erythrocyte ghost membrane microviscosity in essential hypertensive patients and to determine the relationship between these changes and the sodium-lithium countertransport activity as a sensitive marker of membrane function. SUBJECTS: Forty-three normolipidaemic essential hypertensive patients (23 treated, 20 untreated) and 27 normotensive controls were studied. Patients were attending the hospital hypertension clinic or a local general practitioner's surgery. METHODS: Erythrocyte sodium-lithium countertransport activity was measured. The Michaelis constant (Km) for extracellular sodium and maximal reaction velocity for sodium-lithium countertransport were measured in a subgroup consisting of 22 essential hypertensive patients and 11 normotensive controls. Erythrocyte membrane microviscosity was measured using fluorescence polarization anisotropy of 1,6-diphenyl-1,3,5-hexatriene (DPH) and 1-[4-trimethylammoniumphenyl]-6-phenyl-1,3,5-hexatriene (TMA-DPH). RESULTS: There was no significant difference in the fluorescence polarization anisotropy of DPH or TMA-DPH between normotensive and essential hypertensive patients. However, the fluorescence polarization anisotropy of TMA-DPH was increased significantly (reflecting increased membrane microviscosity) in hypertensive patients with a family history of hypertension compared with in patients without a family history of hypertension. The standard sodium-lithium countertransport activity was elevated in essential hypertensive patients compared with normotensive controls, and the Km for sodium was significantly lower in patients with a family history of hypertension than in patients without a family history of hypertension. Patients with a family history of hypertension were clustered, with significantly lower Km for sodium and higher TMA-DPH anisotropies than either hypertensive patients without a family history of hypertension or normotensive controls. CONCLUSIONS: These findings suggest that a high membrane microviscosity affecting the outer region of the lipid bilayer is associated with altered sodium-lithium countertransport kinetics in a subgroup of essential hypertensive patients consisting of those with a family history of hypertension.

Antiporters↗
PubMed1995

Elevated frequency of glycophorin A mutations in erythrocytes from Chernobyl accident victims.

In 1986, when an explosion accident occurred at the Chernobyl, Ukraine nuclear power plant, a large number of people were exposed to significant amounts of ionizing radiation. During the time between 1986 and 1992, peripheral blood samples were obtained from 102 people who either were on site during the emergency or were brought to Chernobyl shortly thereafter to assist in the cleanup of radioactive contaminants and isolate the damaged reactor from the environment. These blood samples plus samples from 13 unexposed Soviet individuals were analyzed by flow cytometry using the allele-loss somatic mutation assay for glycophorin A. Results of these assays show that the frequency of N/O variant red cells increased in proportion to the estimated radiation exposure of each individual. The radiation dose-response function derived from this population closely resembles that determined previously for atomic bomb survivors whose blood samples were obtained and analyzed 40 years after their exposure. This suggests comparable mutation induction per unit dose for these two populations and long-term persistence of the mutational damage. In addition, measurements on multiple blood samples from each of 10 donors taken over a 7-year period showed no significant changes in N/O variant cell frequencies, confirming the persistence of radiation-induced somatic mutations in long-lived bone marrow stem cells.

Dose-Response Relationship, Radiation↗
PubMed1994

Novel synthesis of cyclic amide-linked analogues of angiotensins II and III.

Cyclic amide-linked angiotension II (ANGII) analogues have been synthesized by novel strategies, in an attempt to test the ring clustering and the charge relay bioactive conformation recently suggested. These analogues were synthesized by connecting side chain amino and carboxyl groups at positions 1 and 8, 2 and 8, 3 and 8, and 3 and 5, N-terminal amino and C-terminal carboxyl groups at positions 1 and 8, 2 and 8, and 4 and 8, and side chain amino to C-terminal carboxyl group at positions 1 and 8. All these analogues were biologically inactive, except for cyclic [Sar1, Asp3, Lys5]ANGII (analogue 10) which had high contractile activity in the rat uterus assay (30% of ANGII) and [Lys1, Tyr(Me)4, Glu8]ANGII (analogue 7) which had weak antagonist activity (PA2 approximately 6). Precyclic linear peptides synthesized using 2-chlorotrityl chloride resin and N alpha-Fmoc-amino acids with suitable side chain protection were obtained in high yield and purity and were readily cyclized with benzotriazol-1-yloxytris(dimethylamino)-phosphonium hexafluorophosphate as coupling reagent. Molecular modeling suggests that the ring structure of the potent analogue can be accommodated in the charge relay conformation proposed for ANGII.

Amino Acid Sequence↗
PubMed1994

Epidermal-growth-factor-receptor expression is associated with rapid tumor proliferation in bladder cancer.

Epidermal-growth-factor-receptor (EGF-r) expression has been proposed as a prognostic marker in bladder cancer and is associated with rapid proliferation in cell lines. Ninety-three fresh and 74 formalin-fixed bladder tumors were examined by fluorescence in situ hybridization (FISH) and immunohistochemistry to assess the relationship between EGF-r expression and proliferation as well as the prevalence of epidermal-growth-factor-receptor (EGF-r) gene amplification. EGF-r expression was strongly associated with BUdr labeling index, grade and stage. EGF-r expression emerged as a stronger predictor of tumor proliferation than grade or stage in analysis of variance. Rapid tumor proliferation might be responsible for bad prognosis reported in EGF-r positive bladder tumors. Also chromosome 7 copy number was associated with grade and stage. EGF-r gene amplification was uncommon (5 of 107 tumors). However, FISH analysis allowed characterization of the pattern of amplification, with clustering of signals suggestive of intrachromosomal amplification more common than diffuse distribution consistent with extrachromosomal amplification.

Bromodeoxyuridine↗
PubMed1994

Preliminary crystallographic studies on human complement pro-factor D.

The recombinant zymogen of the human complement protein factor D has been crystallized. Crystals were grown by vapor diffusion using polyethylene glycol 6000 as precipitant. Two crystal forms obtained at pH 5.4 belong to space group P2(1). The crystals grow to dimensions of 0.6 mm x 0.3 mm x 0.3 mm in three days, are stable in the X-ray beam, and diffract to 2.4 A.

Amino Acid Sequence↗
PubMed1994

Structure of human factor D. A complement system protein at 2.0 A resolution.

Factor D, an essential enzyme for the activation of the alternative pathway of the complement system, belongs to the serine protease superfamily. The crystal structure of the enzyme was solved by a combination of multiple isomorphous replacement and molecular replacement methods. The present model was refined to an R-factor of 18.8% using 23,681 observed reflections between 7.5 and 2.0 A resolution, with a root-mean-square deviation from standard bond lengths of 0.016 A. The two non-crystallographically related molecules in the triclinic unit cell have distinctive active site conformations. The protein has the general structural fold of a serine protease, but there are several unique amino acid substitutions resulting in significant alterations in the critical loops responsible for catalysis and substrate specificity in serine proteases. Factor D is the first complement serine protease whose three-dimensional structure has been determined.

Amino Acid Sequence↗
PubMed1994

Nucleotide sequence of the P1 region of serotype Asia1 foot-and-mouth disease virus.

Differences in the amino acid sequence of foot-and-mouth disease virus (FMDV) virion proteins (VP) among the various FMDV serotypes, particularly in the VP1 polypeptide, are the basis for antigenic diversity of this virus group. This phenomenon provides the basis for type diagnosis of FMDV by the polymerase chain reaction (PCR). In order to specifically identify the Asia1 FMDV serotype by PCR, the nucleotide sequence of its P1-coding region was determined. The sequence exhibited over 70% homology with the P1 gene segment of type O1k. The deduced amino acid sequence shares 79% homology with that of the P1 region of serotype O1k.

Amino Acid Sequence↗