Biomedical subjects

C D Miller

Publications and source records attributed to C D Miller.

At least 19 recordsLinked to original sources

PubMed1991

The gene encoding ovine follicle-stimulating hormone beta: isolation, characterization, and comparison to a related ovine genomic sequence.

Follicle-stimulating hormone (FSH), the primary stimulus for egg and sperm maturation in mammals, is an alpha/beta heterodimer. Each subunit is encoded by a single-copy gene in the human, bovine, and rat genomes. Transcription of both subunits is inhibited by estradiol and progesterone in ovine pituitary cultures. We report the sequence of one ovine FSH-beta gene (-1,527 to +3,664) that is expressed in vivo and the identification of a novel, second ovine FSH-beta-like sequence. Digestion of ovine genomic DNA with Bgl II yielded two fragments of 10 kb and 15 kb that hybridized to a bovine FSH-beta cDNA. The 10-kb fragment contained 6 kb of 5'-flanking region and all but about 200 bp of the 3' terminus of the ovine FSH-beta gene. This FSH-beta gene encodes a protein that differs from the published ovine protein sequence only at the carboxy terminus (Arg-109Glu-110[STOP codon] instead of Glu-109Arg-110[Glx-111]) and at positions 49 (Ala instead of Thr) and 88 (Arg instead of Ser). This gene is organized similarly to the human, bovine, porcine, and rat FSH-beta genes, and its coding sequence is nearly identical (99.5%) to a reported ovine FSH-beta cDNA. Expression of the FSH-beta gene on the 10-kb fragment in vivo was determined by analysis of wether mRNA using the polymerase chain reaction. A 95-bp sequence of the 15-kb fragment was 87% homologous to the corresponding coding region of the 10-kb fragment. This comparison suggested that the 15-kb fragment contains either an FSH-beta-like sequence or a pseudogene. Several potential steroid response elements were found by sequence analysis of the 5'-flanking region of the FSH-beta gene on the 10-kb fragment. A mechanism by which these elements may act is suggested.

Amino Acid Sequence↗

PubMed1991

A monoclonal antibody defines a geographically conserved surface protein epitope of Babesia equi merozoites.

Babesiosis is a tick-borne hemoparasitic disease affecting horses worldwide. To investigate mechanisms of immunity to this parasite, the antibody response of infected horses to Babesia equi merozoite proteins was evaluated. Immunoprecipitation of B. equi merozoite antigens with sera from infected horses revealed 11 major proteins of 210, 144, 108, 88, 70, 56, 44, 36, 34, 28, and 25 kDa. Monoclonal antibody (MAb) 36/133.97, which binds to live merozoites, immunoprecipitated proteins of 44, 36, 34, and 28 kDa. When immunoprecipitations were performed with in vitro translation products of merozoite mRNA, MAb 36/133.97 immunoprecipitated proteins of 38, 28, 26, and 23 kDa which comigrated with proteins immunoprecipitated by sera from infected horses at 10(-3) to 10(-4) dilutions. In Western blot analysis, MAb 36/133.97 recognized proteins of 44, 36, 34, and 28 kDa, and a 28-kDa protein was identified by sera from infected horses at a dilution of 10(-4). MAb 36/133.97 bound to B. equi isolates from Florida and Europe. Furthermore, the binding of MAb 36/133.97 to merozoite proteins was inhibited by sera of infected horses from 19 countries. Collectively, these data indicate MAb 36/133.97 binds to a geographically conserved peptide epitope on multiple B. equi merozoite proteins, including a merozoite surface protein, and MAb 36/133.97 reacts with a B. equi protein immunodominant in infected horses.

Animals↗

PubMed1990

Ultraviolet light-induced DNA damage in transcribed sequences: no change in repair with age.

We studied the repair of a plasmid vector containing the chloramphenicol acetyltransferase (CAT) gene by treating the plasmid with UV light and then transfecting this plasmid into fibroblasts from human fetal lung (in vitro aging) and into primary cultured fibroblasts from rat lung and skin. This methodology allows us to examine the repair of specific transcribed DNA sequences. There was no age-related change in the repair of UV damage in these cells. Rat embryo fibroblasts at different passages transfected with the plasmid also revealed no significant alteration in UV repair as a function of passage number.

Aging↗

PubMed1990

DNA alterations in prostatic adenocarcinoma and benign prostatic hyperplasia: detection by DNA fingerprint analyses.

DNA fingerprinting can be utilized to examine a large number of autosomal loci throughout the human genome. Alterations in banding patterns observed on DNA fingerprint analyses reflect DNA alterations ranging from single base changes to complex chromosomal rearrangements. In this report, we describe the application of this technique to prostatic adenocarcinoma (CAP) and benign prostatic hyperplasia (BPH). The majority of CAP cases (12 of 14) displayed alterations in at least 1 of the approximately 30 resolvable bands obtained by fingerprint analyses when compared with DNA obtained from peripheral white blood cells. Unexpectedly, 5 of the 12 cases of BPH examined revealed at least 1 identifiable band alteration in the prostatic tissue. These findings demonstrate the usefulness of fingerprint analyses in the examination of cancer-associated genetic alterations. They also suggest the presence of observable genetic alterations in BPH.

Adenocarcinoma↗

PubMed1990

IV lignocaine fails to attenuate the cardiovascular response to laryngoscopy and tracheal intubation.

I.v. lignocaine has been used with varying success to attenuate the cardiovascular responses to laryngoscopy and tracheal intubation. We determined the optimal time of administration in 45 ASA I and II Chinese patients premedicated with morphine and hyoscine, and anaesthetized with thiopentone and suxamethonium. Patients were allocated randomly to a control group or three treatment groups to receive lignocaine 1.5 mg kg-1 i.v. 1, 2, or 3 min before laryngoscopy. Analysis of variance for measured and derived cardiovascular variables failed to show any significant difference between any of the groups.

Adult↗

PubMed1990

Pupillary effects of alfentanil and morphine.

We have measured the onset and extent of the miotic effect of morphine and alfentanil in conscious patients. Forty unpremedicated ASA I and II patients were allocated randomly to four groups to receive either i.v. saline (control group), morphine 0.1 mg kg-1, alfentanil 4.0 micrograms kg-1 or a combination of these doses, and pupil diameters were measured for the next 30 min. There were no significant differences in the control diameters. In the opioid groups, a significant decrease in diameter (about 1 mm), occurred 4 min after administration of the drug and persisted throughout the study. The opioid groups behaved similarly for 25 min. After 10 min the mean diameter of the alfentanil group began to increase, but this did not reach statistical significance until after 25 min.

Adult↗

PubMed1990

Effect of isoflurane on the canine hepatic circulation and hepatic oxygen balance.

We have studied the effects of increasing concentrations of isoflurane (1%, 1.5% and 2%) on the hepatic circulation and the oxygen supply and demand of the liver in six barbiturate-anaesthetized greyhounds. Following laparotomy, the hepatic arterial and portal venous blood flows were measured continuously using electromagnetic flow probes, and mean arterial pressure and cardiac output were measured as appropriate. Cardiac output was maintained while mean arterial pressure and systemic vascular resistance decreased in a dose dependent manner. Hepatic arterial and total liver blood flows and oxygen supplies decreased significantly at all isoflurane concentrations. Portal venous blood flow and portal venous oxygen supply did not decrease significantly until the concentration of isoflurane was increased to 2% and 1.5%, respectively. Hepatic oxygen consumption was reduced with 2% isoflurane (P less than 0.05), but this was insufficient to offset the reduction in hepatic oxygen supply and resulted in an increased extraction of oxygen by the liver.

Anesthesia, General↗

PubMed1990

Recurrent bronchospasm during anaesthesia.

Bronchospasm complicated several anaesthetics in a diabetic patient with chronic renal failure. The bronchospasm was accompanied frequently by bradycardia. The pathophysiology, treatment and implications for future anaesthetic management are discussed.

Adult↗

PubMed1990

The ballet technique shoe: a preliminary study of eleven differently modified ballet technique shoes using force and pressure plates.

Ballet dancers are vulnerable to various stress-related injuries; foot and ankle injuries are the most common. This study determined if the pressure across the foot could be more evenly distributed by wearing various modified technique shoes padded with PPT, Spenco, or Sorbathane, alone or in combinations. A professional ballet dancer performed a jump by taking a single step on his left foot, jumping and landing with his right foot on the force and pressure plates with each modified shoe plus one unmodified shoe. The results of this study revealed: (1) total force cannot be reduced, (2) center of gravity and the majority of the pressure is maintained over the first and second metatarsal heads, and (3) the modified technique shoe can more evenly distribute pressure to the medial arch and away from the toes, metatarsal heads, and heel.

Athletic Injuries↗

PubMed1990

In vitro effects of cyclopiazonic acid mycotoxin on turkey papillary muscles.

An in vitro bioassay system was used to study the effects of cyclopiazonic acid (CPA) mycotoxin on cardiac muscle. Acute exposure to 6 micrograms of CPA/ml of modified Krebs-Henseleit solution significantly (P less than 0.05) decreased 5 in vitro turkey cardiac muscle performance criteria: maximal weight a muscle could lift; maximal contraction velocity; relaxation velocity; time to peak contraction; and total time for muscle contraction and relaxation. The effect on these 5 criteria appeared to result from intracellular changes partially associated with calcium availability and were irreversible, suggesting that physiologic changes had developed after acute exposure to CPA.

Animals↗

PubMed1990

Comparison of enflurane and halothane in hypotensive eye surgery.

Thirty patients undergoing elective eye surgery had anaesthesia induced with sodium thiopentone, suxamethonium and d-tubocurarine chloride. Patients were ventilated with nitrous oxide, oxygen and either halothane or enflurane. The volatile agents were used to decrease the systolic blood pressure to 80 mmHg. The volatile agent concentration in the blood was measured at 30 min intervals. Both agents were effective in producing hypotension, but enflurane was the more potent hypotensive agent in terms of MAC equivalents. There was no significant differences between the agents with respect to speed of recovery.

Adolescent↗

PubMed1989

Human gamma-glutamyl transpeptidase cDNA: comparison of hepatoma and kidney mRNA in the human and rat.

gamma-Glutamyl transpeptidase (GGT) is a glutathione-metabolizing enzyme that has been extensively studied in relation to hepatocarcinogenesis. Using a cDNA for rat kidney GGT as a probe, we have isolated a full-length cDNA for human GGT from a hepatoma cell-line library. Nucleotide sequence analysis of the clone revealed a 2326-bp insert that includes a 5'-untranslated region of 487 nucleotides (nt), an open reading frame (ORF) of 1707 nt, and a 3'-untranslated region of 132 nt. The ORF encodes a protein with an amino acid sequence that is highly similar to that of the rat GGT precursor peptide, with an overall identity of 79%. The cDNA clone was used to probe Northern blots of hepatoma and kidney RNA from both human and rat. In both species, the GGT mRNA is longer in hepatoma than in kidney. In addition, the human mRNAs were longer than their counterparts in the rat. None of three human hepatocellular carcinomas examined showed a marked elevation in GGT mRNA levels relative to surrounding liver tissue.

Amino Acid Sequence↗

PubMed1989

Fine structural defects in a case of congenital microcoria.

A case of congenital miosis associated with myopia and cataract is described. Tissue obtained at iridectomy was examined with the electron microscope and compared with a specimen of normal iris. The miotic iris was found to be hypoplastic and to display differences in the cellular density of the stroma. The contractile processes of the dilator myoepithelium were conspicuously absent from the underlying stroma, and the existing myofibrils were much disarranged.

Adult↗

PubMed1989

Effect of a high-intensity static magnetic field on sciatic nerve regeneration in the rat.

The effect of a high-intensity static magnetic field on peripheral nerve regeneration is evaluated in rat sciatic nerve. Forty-four rats underwent sciatic nerve repair using polyethylene nerve guides. Postoperatively, the animals were exposed to a 1-tesla magnetic field for 12 hours per day for 4 weeks with appropriate controls. Our results demonstrate that a 1-tesla static magnetic field has no statistically significant effect on nerve regeneration as determined by myelinated axon counts and electrophysiologic studies. Also, the specific orientation of the sciatic nerve with respect to the magnetic field has no influence on axonal growth or nerve conduction. Periods of restraint of 12 hours per day for 4 weeks significantly inhibit weight gain but have no effect on peripheral nerve regeneration.

Animals↗

PubMed1989

Outpatient paediatric dental anaesthesia. A comparison of halothane, enflurane and isoflurane.

One hundred and fifty unpremedicated children who presented for dental extractions were anaesthetised with nitrous oxide and halothane, enflurane or isoflurane. Ventricular arrhythmias occurred only in the halothane group (14%). Respiratory problems and desaturation were significantly more common in the isoflurane group. Induction times differed significantly between the groups halothane less than enflurane less than isoflurane, while recovery time and induction to recovery time were significantly shorter in the enflurane group. We suggest that enflurane is the most suitable agent for anaesthetising these patients.

Ambulatory Surgical Procedures↗

PubMed1988

Silent regurgitation in day case gynaecological patients.

The effect of metoclopramide premedication on the incidence of gastric regurgitation and postoperative nausea and vomiting was studied in 101 women during gynaecological procedures performed under mask anaesthesia. All patients were premedicated orally with carmine red and temazepam. A treatment group of 48 women also received oral metoclopramide. Anaesthesia was standardised in both groups. None of the women regurgitated gastric contents. Pharyngeal pH was measured in the last 68 patients and found to be greater than 5 in all instances. Postoperative nausea and vomiting were significantly less frequent in the treatment group.

Adult↗

PubMed1988

Rationales for the use of alcohol, marijuana, and other drugs by eighth-grade native American and Anglo youth.

This study examined rationales for alcohol, marijuana, and other drug use among Indian and non-Indian youth. Differences were found between reservation Indian and rural non-Indian rationales for alcohol, marijuana, and other drug use. A majority of both Indian and non-Indian eighth graders indicate that they use drugs to enhance positive affective states, for excitement, for parties, to be with friends, to relax, and to handle negative affective states including worries and nervousness. Indian youth appear to also use drugs to cope with boredom. Unlike non-Indian youth, Indian youth have no strong rationales for their use of other drugs. Interventions will have to be impactful and pervasive in order to counter the many positive and negative rationales associated with drug use.

Adaptation, Psychological↗

PubMed1988

In vitro evaluation of isolated turkey cardiac muscle function.

Turkey papillary muscles can function in an isolated chamber containing oxygenated, pH-regulated, modified Krebs-Henseleit solutions. Experiments were conducted for up to 6 hr without dimunition of muscle function. Our data indicate that different calcium concentrations affect muscle contraction and relaxation velocities, load values, and latencies. This controlled in vitro biological assay system can be used in further studies to evaluate species specific cardiac toxins or drugs.

Animals↗