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D Moore

Publications and source records attributed to D Moore.

At least 73 records · Page 4Linked to original sources
PubMed1987

Remissions in hairy-cell leukemia with pentostatin (2'-deoxycoformycin).

The Eastern Cooperative Oncology Group conducted a study of pentostatin (2'-deoxycoformycin) in 37 patients with hairy-cell leukemia. Among the 27 patients who met all the study's entry criteria, the response rate was 96 percent, with 16 patients (59 percent) entering complete remission and 10 patients (37 percent) partial remission. In one patient no response was observed. These results were not significantly changed by the inclusion of nine additional patients who were found retrospectively not to have fulfilled the entry criteria. When complete remission was attained, maintenance therapy was not given. Despite this, no patient has had a relapse, and the duration of complete remission ranges from 1 to 375 days. Pentostatin appears to be equally effective in untreated patients and in those who have progressive disease after splenectomy or after both splenectomy and treatment with interferon. Whether pentostatin is superior to splenectomy or interferon as therapy for hairy-cell leukemia will have to be assessed by direct comparison in randomized studies. Lengthy follow-up will be required to determine a median duration for the responses of hairy-cell leukemia to pentostatin.

Antineoplastic Agents↗
PubMed1987

Neural control of a cyclic postural behavior in the crayfish, Procambarus clarkii: the pattern-initiating interneurons.

As part of its repertoire of defensive behaviors, the crayfish, Procambarus clarkii, may respond to mildly threatening tactile or visual stimuli from the front of its body by walking backwards. During this behavior, the abdomen undergoes complex cyclical movements involving flexion and extension of the postural musculature which cause the tail to alternately contact and withdraw from the substrate. Intracellular neuropil recordings and dye injections were used to search for the interneurons responsible for initiating this postural motor pattern in the crayfish abdomen. Several diverse morphological types of interganglionic pattern-initiating (PI) interneurons were found. Each interneuron, when driven intracellularly, was capable of eliciting the same motor program, in its entirety, throughout the abdominal nerve cord. During pattern generation, PI interneurons exhibited a burst of spikes preceding the motor output. Silencing single PI interneurons with hyperpolarizing current during pattern generation failed to affect the motor program, indicating a redundancy of pattern-initiating function. The observations of extensive dye-coupling with other parallel axons, consistent dye-coupling with other identified cells in the pattern-initiating system, and the presence of multiple spike amplitudes in the bursts suggested electrotonic coupling among the PI interneurons. An additional group of interganglionic interneurons, the partial pattern-initiating (PPI) interneurons, were found to comprise a significant subset of the pattern-initiating system. As with the PI cells, the PPI interneurons exhibited a complex burst of spikes just preceding the patterned motor program. However, the PPI interneurons were only capable of eliciting an incomplete, though recognizable, postural motor pattern. Silencing any PPI interneuron during pattern generation caused a deficit in the motor pattern, indicating either an absence or lesser degree of functional redundancy within the PPI interneuron population compared to that occurring within the PI interneuron group. We conclude that a large number of PI interneurons are presynaptic to a relatively small group of PPI interneurons which, in turn, conduct pattern-initiating signals to the ganglionic oscillators. Our results indicate that pattern-initiation is accomplished through a command system involving multiple command elements organized in a coordinated interganglionic network.

Animals↗
PubMed1987

Analysis of Escherichia coli K12 F factor transfer genes: traQ, trbA, and trbB.

The genes that encode the transfer properties of plasmid F, the fertility factor of Escherichia coli K12, are known to be clustered over a large, 33.3-kb segment of F DNA. As the central segment of the transfer region has not previously been well characterized, we constructed a detailed restriction map of the large F EcoRI DNA fragment, fl, and isolated a series of plasmid derivatives that carry various overlapping segments of this F tra operon DNA. We also analyzed the protein products of those clones that carried DNA segments extending over the region between traF and traH. This region was known to include traQ, a gene required for efficient conversion of the direct product of traA to the 7000-Da pilin polypeptide. We identified the traQ product as a polypeptide that migrates as a 12,500-Da protein on sodium dodecyl sulfate-polyacrylamide gels. We also detected the products of two other new genes that we have named trbA and trbB. These polypeptides migrate with apparent molecular weights of 14,200 and 18,400, respectively. Analysis of plasmid deletion derivatives that we constructed in vitro shows that these genes map in the order traF trbA traQ trbB traH. The presence of a plasmid carrying a small 0.43-kb fragment that expressed only the 12,500 traQ product caused the traA product of a co-resident compatible plasmid to be converted to the 7000-Da pilin polypeptide, demonstrating that TraQ is the only tra operon product required for this step of F-pilin biosynthesis.

Bacteriophage lambda↗
PubMed1987

Familial renal abnormalities associated with the oligohydramnios tetrad secondary to renal agenesis and dysgenesis.

Thirty-four families of index cases with the oligohydramnios tetrad secondary to renal agenesis/dysgenesis were screened for renal abnormalities using Real Time ultrasonography. The index cases were separated into two groups. Group 1 consisted of cases of perinatally lethal renal disease and Group 2 of cases of renal dysgenesis secondary to the urethral obstruction malformation. Renal ultrasound screenings of 23 families in Group 1 demonstrated two previously unidentified cases of unilateral renal agenesis in siblings. Screening of 11 families in Group 2 revealed one sibling with a hydronephrotic kidney and one parent with an ectopic pelvic kidney. There is a recurrence risk of 3.5-5% in families with perinatal lethal renal disease and an increased risk of silent renal anomalies in first degree family members. The recurrence risk is low in families of infants with renal dysgenesis secondary to the urethral obstruction malformation, but immediate family members are at increased risk of structural and functional urinary anomalies. Routine renal ultrasound screening of first degree relatives of infants with lethal renal agenesis and dysgenesis is recommended.

Amniotic Fluid↗
PubMed1987

Location of F plasmid transfer operon genes traC and traW and identification of the traW product.

As part of an analysis of the conjugative transfer genes associated with the expression of F pili by plasmid F, we have investigated the physical location of the traC and traW genes. We found that plasmid clones carrying a 2.95-kilobase EcoRI-EcoRV F transfer operon fragment were able to complement transfer of F lac traC mutants and expressed an approximately 92,000-dalton product that comigrates with TraC. We also found that traW-complementing activity was expressed from plasmids carrying a 900-base-pair SmaI-HincII fragment. The traW product was identified as an approximately 23,000-dalton protein. The two different F DNA fragments that expressed traC and traW activities do not overlap. Our data indicate that the traC gene is located in a more-tra operon promoter-proximal position than suggested on earlier maps and that traW is distal to traC. These results resolve a long-standing question concerning the relationship of traW to traC. The clones we have constructed are expected to be useful in elucidating the role of proteins TraC and TraW in F-pilus assembly.

Bacterial Proteins↗
PubMed1987

Analysis of transfer genes and gene products within the traB-traC region of the Escherichia coli fertility factor, F.

A series of plasmids that carry overlapping segments of F DNA encoding the genes in the traB-traC interval was constructed, and a restriction enzyme map of the region was derived. Plasmids carrying deletions that had been introduced at an HpaI site within this interval were also isolated. The ability of these plasmids to complement transfer of F lac plasmids carrying mutations in traB, traV, and traW, and traC was analyzed. The protein products of the plasmids were labeled in UV-irradiated cells and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. These analyses showed that the product of traV is a polypeptide that migrates with an apparent molecular weight of 21,000. It was not detected when [35S]methionine was used to label plasmid products, but was readily detected in 14C-amino acid labeling experiments. A 21,500-dalton product appeared to stem from the region assigned to traP. A 9,000-dalton product was found to stem from a locus, named traR, that is located between traV and traC. No traW activity could be detected from the region of tra DNA examined. Our data also indicated that traC is located in a more promoter-proximal position than suggested on earlier maps. The plasmids constructed are expected to be useful in studies designed to identify the specific functions of the traB, -P, -V, -R, and -C products.

Autoradiography↗
PubMed1987

Morbidity after percutaneous liver biopsy.

The safety of percutaneous liver biopsy with a 1.2 mm Menghini needle in infants aged one year or less was investigated. One hundred and eighty four procedures performed from 1975 to 1985 were reviewed. There were no deaths or major complications within 48 hours associated with the procedure. In five instances specific complications occurred: a drop in haemoglobin concentration (three), transient hypotension (one), and haematoma at the biopsy site (one). The result of liver biopsy was diagnostic in 83% of cases, compatible with unspecified metabolic disease in 8%, and normal or not diagnostic in 9%. This study suggests that percutaneous liver biopsy can be performed with relative safety in small infants if coagulation is normal and there are no major contraindications, and the results yield important diagnostic information which cannot be obtained using less invasive procedures.

Biopsy, Needle↗
PubMed1986

Hepatitis A virus replication in tamarins and host immune response in relation to pathogenesis of liver cell damage.

Hepatitis A virus (HAV) shedding in the faeces, appearance of HAV-Ag (antigen) in the liver, and development of humoral immunity to HAV have been studied in experimentally infected tamarins. The appearance of liver damage measured by transaminase elevation and histology, in relation to the above variables, suggests that the virus is not cytopathic and the immune system contributes to the production of liver cell damage. Preliminary data suggest that HAV replication may occur in the mucosa of the small intestine and in the liver.

Animals↗
PubMed1986

Effects on the rabbit carotid body of stimulation by almitrine, natural high altitude, and experimental normobaric hypoxia.

Rabbits were given intraperitoneal injections of almitrine in ascending doses for 5 weeks. They were compared with a control group and with a group of rabbits which had been exposed from birth to the natural hypobaric hypoxia found at Cerro de Pasco (433 m) in the Peruvian Andes. A further group of animals was placed in an experimental normobaric chamber for either 3 or 6 months to subject them to the same degree of hypoxia as that occurring in Cerro. The carotid bodies of the rabbits in all these groups were processed for light and electron microscopy, and examined both qualitatively and quantitatively. The carotid bodies in the group given almitrine showed no changes in their size or in the population of their glomic cells when compared with controls. In contrast, the carotid bodies of Peruvian rabbits were greatly enlarged with a disproportionate increase in the population of the light variant of chief cell. Rabbits from the hypoxic chamber also had enlarged carotid bodies but those killed after 3 months showed an increase in the dark variant of chief cell, whereas after 6 months this cell was reduced in number. There was also intense cytoplasmic vacuolation. Election microscopy confirmed these changes and revealed that dark cells had larger, more pleomorphic granules than the light variant. Vacuolation of the granules in light cells was most pronounced in Peruvian rabbits, but was uncommon in animals exposed to hypoxia for 3 months. We suggest that the dark cell responds to the early stages of hypoxia but later matures into the light variant of chief cell.

Almitrine↗
PubMed1986

Chronic intussusception due to antral myoepithelioma.

Intussusception was seen on abdominal sonography and computed tomography in a 15-year-old boy who presented with a 6-week history of weight loss, vomiting, abdominal pain, abdominal mass, and hyperamylasemia. Laparotomy revealed a chronic gastroduodenal intussusception, the lead point of which was an antral myoepithelioma, a rare entity in this age group.

Adolescent↗
PubMed1986

Operative recovery of vasal sperm from anejaculatory men: preliminary report.

Sperm showing good motility and function, as demonstrated by the in vitro sperm penetration assay using hamster ova, were collected from the vas deferens of 3 men with ejaculatory failure. The collection procedure may be repeated over multiple ovulatory cycles. The sperm may be used to attempt artificial insemination or in vitro fertilization.

Adult↗
PubMed1986

Eosinophilic gastroenteritis presenting in an adolescent with isolated colonic involvement.

Eosinophilic gastroenteritis most commonly involves the stomach and proximal small intestine with eosinophilic inflammation of either the mucosa, submucosa or serosa. The patient reported here had isolated eosinophilic colitis. The initial presentation with iron deficiency anaemia owing to occult gastrointestinal blood loss emphasises the need to evaluate the entire gastrointestinal tract in patients with eosinophilic gastroenteritis.

Adolescent↗