Biomedical subjects

C L Moore

Publications and source records attributed to C L Moore.

At least 37 records · Page 2Linked to original sources

PubMed1997

Intersitial deletion of 20p: new candidate region for Hirschsprung disease and autism?

We describe a patient with Hirschsprung disease and autism. High-resolution karyotyping indicated that the patient has an interstitial deletion of 20p11.22-p11.23. Microsatellite analysis showed a deletion involving a 5-6 cM region from the maternally derived chromosome 20. The deleted region is proximal to, and does not overlap, the recently characterized Alagille syndrome region. This region of 20p has not yet been implicated in Hirschsprung disease or autism. However, this region contains several genes that could plausibly contribute to any phenotype that includes abnormal neural development.

Alagille Syndrome↗

PubMed1997

Cleavage factor II of Saccharomyces cerevisiae contains homologues to subunits of the mammalian Cleavage/ polyadenylation specificity factor and exhibits sequence-specific, ATP-dependent interaction with precursor RNA.

Cleavage of pre-mRNA during 3'-end formation in yeast requires two protein factors, cleavage factor I (CF I) and cleavage factor (CF II). A 5300-fold purification of CF II indicates that four polypeptides of 150, 105, 100, and 90 kDa copurify with CF II activity. The 150-kDa protein is recognized by antibodies against Cft1, the yeast homologue of the 160-kDa subunit of the mammalian cleavage/polyadenylation specificity factor (CPSF). The 100-kDa subunit is identical to Brr5/Ysh1, a yeast protein with striking similarity to the 73-kDa subunit of CPSF. The 105-kDa protein, designated Cft2 (cleavage factor two) exhibits significant homology to the CPSF 100-kDa subunit. Cft2 is cross-linked to pre-mRNA substrate containing the poly(A) site and wild type upstream and downstream flanking sequences, but not to precleaved RNA lacking downstream sequences or to substrate in which the (UA)6 processing signal has been deleted. The specific binding of Cft2 to the RNA substrate is ATP-dependent, in agreement with the requirement of ATP for cleavage. The sequence-specific binding of Cft2 and the similarities of CF II subunits to those of CPSF supports the hypothesis that CF II functions in the cleavage of yeast mRNA 3'-ends in a manner analagous to that of CPSF in the mammalian system. These results provide additional evidence that certain features of the molecular mechanism of mRNA 3'-end formation are conserved between yeast and mammals, but also highlight unexpected differences.

Adenosine Triphosphate↗

PubMed1997

The Uba2 and Ufd1 proteins of Saccharomyces cerevisiae interact with poly(A) polymerase and affect the polyadenylation activity of cell extracts.

Poly(A) polymerase is responsible for the addition of the adenylate tail to the 3' ends of mRNA. Using the two-hybrid system we have identified two proteins which interact specifically with the Saccharomyces cerevisiae poly(A) polymerase, Pap1. Uba2 is a homolog of ubiquitin-activating (E1) enzymes and Ufd1 is a protein whose function is probably also linked to the ubiquitin-mediated protein degradation pathway. These two proteins interact with Pap1 and with each other, but not with eight other target proteins which were tested in the two-hybrid system. The last 115 amino acids of Uba2, which contains an 82-amino acid region not present in previously characterized E1 enzymes, is sufficient for the interaction with Pap1. Both Uba2 and Ufd1 can be co-immunoprecipitated from extracts with Pap1, confirming in vitro the interaction identified by two-hybrid analysis. Depletion of Uba2 from cells produces extracts which polyadenylate precursor RNA with increased efficiency compared to extracts from nondepleted cells, while depletion of Ufd1 yields extracts which are defective in processing. These two proteins are not components of polyadenylation factors, and instead may have a role in regulating poly(A) polymerase activity.

Cloning, Molecular↗

PubMed1997

Intravenous phenylephrine preconditioning of cardiac grafts from non-heart-beating donors.

BACKGROUND: Hypoxia and warm ischemia produce severe injury to cardiac grafts harvested from non-heartbeating donors. To potentially improve recovery of such grafts, we studied the effects of intravenous phenylephrine preconditioning. METHODS: Thirty-seven blood-perfused rabbit hearts were studied. Three groups of non-heart-beating donors underwent intravenous treatment with phenylephrine at 12.5 (n = 8), 25 (n = 7), or 50 microg/kg (n = 7) before initiation of apnea. Non-heart-beating controls (n = 8) received saline vehicle. Hypoxic cardiac arrest occurred after 6 to 12 minutes of apnea, followed by 20 minutes of warm in vivo ischemia. A 45-minute period of ex vivo reperfusion ensued. Nonischemic controls (n = 7) were perfused without antecedent hypoxia or ischemia. RESULTS: Phenylephrine 25 microg/kg significantly delayed the onset of hypoxic cardiac arrest compared with saline controls (9.6 +/- 0.5 versus 7.7 +/- 0.4 minutes; p = 0.00001), yet improved recovery of left ventricular developed pressure compared with saline controls (57.1 +/- 5.3 versus 41.0 +/- 3.4 mm Hg; p = 0.04). Phenylephrine 25 microg/kg also yielded a trend toward less myocardial edema than saline vehicle (p = 0.09). CONCLUSIONS: Functional recovery of nonbeating cardiac grafts is improved by preconditioning. We provide evidence that the myocardium can be preconditioned with phenylephrine against hypoxic cardiac arrest.

Analysis of Variance↗

PubMed1997

Mother-infant interactions in two strains of rats: implications for dissociating mechanism and function of a maternal pattern.

Mother-infant interaction was observed in Long-Evans and Fischer 344 rats after fostering within or across strains. Interactions immediately following introduction of foster pups to the cage as well as undisturbed interactions with resident litters were examined. Some differences were related to alien status, some to strain of pups, and others to strain of dams. Greater responsiveness to pups of the maternal strain was exhibited in retrieval and body licking. Long-Evans pups received more crouching from dams of both strains 3-12 days postpartum, perhaps because they are significantly larger. Regardless of pup strain, Long-Evans dams engaged in more maternal licking than did F344 dams, and this was more likely directed to the anogenital region. Dams of both strains were more likely to lick male than female pups, regardless of pup strain. The strain difference in maternal licking is consistent with adult strain differences in water and salt appetite and may contribute developmentally to the superior copulatory performance of Long-Evans males.

Animals↗

PubMed1996

Purification of the Saccharomyces cerevisiae cleavage/polyadenylation factor I. Separation into two components that are required for both cleavage and polyadenylation of mRNA 3' ends.

The cleavage/polyadenylation factor I (CF I) is one of four factors required for mRNA 3' end formation in the yeast Saccharomyces cerevisiae. Here we describe the purification of CF I and its separation into two components, CF IA and CF IB. Both components are needed to reconstitute CF I activity in cleavage and poly(A) addition. CF IA consists of a complex of four polypeptides of 76, 70, 50, and 38 kDa, and CF IB is a single 73-kDa polypeptide. The 76- and 38-kDa subunits of CF IA correspond to the previously identified RNA14 and RNA15 proteins. The RNA14 protein, but not the 70- or 50-kDa proteins, coimmunoprecipitates with the RNA15 protein, indicating that RNA14 and RNA15 proteins exist in a tight complex. RNA15 is the only subunit of CF I that can be cross-linked to pre-mRNA.

Chromatography, Ion Exchange↗

PubMed1996

Comparison of costs for infusion versus bolus chemotherapy administration: analysis of five standard chemotherapy regimens in three common tumors--Part one. Model projections for cost based on charges.

BACKGROUND: The cost of infusional administration of cancer chemotherapy has been assumed to be more expensive than the traditional bolus schedule related to the use of durable medical equipment and other components of the delivery system. The objective was to develop a model of projected charges as a basis for the cost estimate for selected common chemotherapy regimens comparing the cost based on charges for bolus and infusional chemotherapy schedules. METHODS: Chemotherapy programs using either bolus or infusional delivery were selected representing standard or commonplace regimens for the treatment of patients with breast cancer (cyclophosphamide, methotrexate, fluorouracil [CMF] or CA); colon cancer (5-fluorouracil[5-FU] infusion vs. 5-FU bolus + leucovorin [LCVI] or lymphoma (cyclophosphamide, hydroxydaunomycin, Oncovin (vincristine), prednisone [CHOP] or CDE [cyclophosphamide, doxorubicin, etoposide]). Cost projections were estimated based on charges and were calculated in a model system using six charge (cost) centers including medical doctor [MD] and/or clinic visit; laboratory; drug cost based on average wholesale price (AWP); cost of disposables; and pump rental fee. Standard dosages were applied for each regimen using total mg/M2 for a 1.5 M2 person. RESULTS: Projected charges or chemotherapy for colon cancer (5-FU infusion vs. 5-FU + LCV) are variable depending on the LCV dose and the infusion duration. The longer infusion duration or higher doses of LCV result in a 40 to 50% increment in monthly charges excluding cost related to toxicity. For breast cancer, the charges for bolus or infusion administration CMF are similar, but for CA bolus charges are higher than infusion charges related to higher drug doses. For lymphoma, CHOP chemotherapy dosage costs are approximately half of those for CDE infusion related to the specific drug regimen and drug dosage used. CONCLUSIONS: The perception that infusional delivery of chemotherapeutic agents adds to the cost of cancer care is appropriate for some regimens but the absolute amount of cost increment is generally modest. The principle cost differences between bolus and infusional schedules relate to drug dosage and the toxicity profile. Generally, but not consistently, infusional schedules use lesser doses and are associated with lesser toxicity. Although the benefit of infusional delivery of chemotherapy in terms of response rates and survival are comparable to bolus schedules for 5-FU infusion and 5-FU + LCV in colon cancer, this has not been established for the regimens analyzed for breast cancer (CMF, CA) or lymphoma (CDE, CHOP). The misperception of cost advantages for bolus delivery should not preclude comparative trials of bolus versus infusional chemotherapy schedules and cost should be studied prospectively in clinical trials comparing different schedules of administration in addition to studies of quality of life and toxicity.

Antibiotics, Antineoplastic↗

PubMed1996

Comparison of costs for infusion versus bolus chemotherapy administration--Part two. Use of charges versus reimbursement for cost basis.

BACKGROUND: The costs of infusion versus bolus administration of chemotherapy has been a point of controversy as has been the method of quantitating the cost. The present study analyzes the reimbursement for chemotherapy administration by infusion compared with bolus delivery based on reimbursement and relates this to cost based on projected charges and actual charges in a private practice setting. METHODS: Actual reimbursement records were retrieved for selected patients receiving infusion or bolus administration of specific chemotherapy regimens for three tumors: colon carcinoma, breast carcinoma, and lymphoma. All services were included except for radiology and hospitalization. Medicare reimbursement represented 90% of the treatment cycles analyzed. RESULTS: Actual reimbursement per month for each infusion regimen was as follows: colon carcinoma, $528 (5-fluorouracil [5-FU]); breast carcinoma, $621 (doxorubicin and cyclophosphamide [AC]) and $685 (cyclophosphamide, methotrexate, and fluorouracil [CMF]); and lymphoma, $603 (cyclophosphamide, doxorubicin, vincristine, and prednisone [CHOP]). Actual reimbursement per month for a bolus regimen was colon carcinoma, $393 (5-FU + leucovorin); breast carcinoma, $991 (AC) or $453 (CMF); and lymphoma, $749 (CHOP). Actual reimbursement represents 21-36% of actual charges. Projected charges based on the model system are generally less than the actual charges. CONCLUSIONS: The cost of chemotherapy as defined by reimbursement are substantially less than actual charges and are also less than projected costs based on charges. Data comparing bolus versus infusion reimbursement costs for colon carcinoma, breast carcinoma, and lymphoma indicate that differences between reimbursement for bolus and infusion administration are not substantial.

Antibiotics, Antineoplastic↗

PubMed1996

Number, size, and regional distribution of motor neurons in the dorsolateral and retrodorsolateral nuclei as a function of sex and neonatal stimulation.

Motor neurons were measured in the retrodorsolateral nucleus (RDLN) and the dorsolateral nucleus (DLN) of adult male and female rats that were reared with normal or reduced levels of maternal anogenital stimulation. In contrast with findings for the spinal nucleus of the bulbocavernosus, which is located in the same spinal segments, reduced stimulation had no effect on neuron number in either nucleus. However, several regional and sex differences were observed. Rostrally located neurons were larger in both the RDLN and the DLN; these location effects were greater in females. There was no sex difference in RDLN neuron size, but DLN neurons were larger in females, particularly in the rostral region. Females had significantly more cells in the RDLN, a nucleus previously considered nondimorphic, whereas males had more DLN neurons. Both regional and sex differences may reflect local differences in trophic factors from targets or afferents.

Animals↗

PubMed1996

Sex differences in sensory and motor branches of the pudendal nerve of the rat.

The morphology of the pudendal nerve was quantified in adult male and female rats. The sensory branch of the pudendal nerve was about three times as large in cross section in males as in females, and the motor branch was about five times as large. Electron microscopy was used to determine the ultrastructural bases of these gross size differences. Differences that were found included greater packing density of both myelinated and unmyelinated axons in females, larger myelinated and unmyelinated axons in males, larger myelin sheaths of sensory axons in males, more numerous myelinated axons in both branches of males, and more numerous unmyelinated axons in the sensory branch of males. There was also some indication that myelinated sensory axons were more likely to branch in the dorsal clitoral nerve of females than in the homologous nerve of males. Morphological differences in the structure of pudendal axons, their associated Schwann cells, and the extracellular matrix as well as differences in sensory and motor axonal number all have potential implications for the sexual differentiation of the central nervous system and behavior.

Animals↗

PubMed1996

Early olfactory experience, novelty, and choice of sexual partner by male rats.

After rearing by citral-scented or unscented dams, adult male rats were given simultaneous choices of citral-scented or unscented female partners in approach, contact, and sexual behavior tests. There was no evidence that mate choice had been affected by the early rearing experience. In Experiment 1, both citral and control males approached citral-scented females in a T-apparatus at slightly above chance levels and exhibited no differences in copulatory behavior during successive pairings. In Experiment 2, normally reared males directed their first mount more rapidly to a citral female, but otherwise mated equally with the scented and unscented females. In Experiment 3, citral-reared males approached citral and unscented females equally, whereas controls approached citral females less often. With 2 females in the same arena (Exp. 3), the first mount was more rapid when the odor of the partner matched that of the dam, but no other measure of sexual behavior was affected by the partner's odor. Despite the importance of early olfactory experience for the development of social behavior, a preference for estrous-related odors is evidently not learned before mating experience. Under some circumstances, a novel odor added to familiar conspecific odors may attract naive males to potential partners.

Acyclic Monoterpenes↗

PubMed1995

Structure-function relationships in the Saccharomyces cerevisiae poly(A) polymerase. Identification of a novel RNA binding site and a domain that interacts with specificity factor(s).

We have constructed deletions in the nonconserved regions at the amino and carboxyl ends of the poly(A) polymerase (PAP) of Saccharomyces cerevisiae and examined the effects of these truncations on function of the enzyme. PAP synthesizes a poly(A) tail onto the 3'-end of RNA without any primer specificity but, in the presence of cellular factors, is directed specifically to the cleaved ends of mRNA precursors. The last 31 amino acids of PAP are dispensable for both nonspecific and specific activities. Removal of the next 36 amino acids affects an RNA binding domain, which is essential for the activity of the enzyme and for cell viability. This novel RNA binding site was further localized using additional deletions, cyanogen bromide cleavage of PAP cross-linked with RNA or 8-azido-ATP, and a monoclonal antibody against a COOH-terminal PAP epitope. A deletion that partially disrupts this domain has reduced nonspecific activity but functions in specific polyadenylation. In contrast, deletion of the first 18 amino acids of PAP has no effect on nonspecific polyadenylation but completely eliminates specific activity. This region is essential for enzyme function in vivo and is probably involved in the interaction of PAP with other protein(s) of the polyadenylation machinery.

Adenosine Triphosphate↗

PubMed1995

Monoclonal antibodies to yeast poly(A) polymerase (PAP) provide evidence for association of PAP with cleavage factor I.

Purified yeast poly(A) polymerase (PAP) was used to produce monoclonal antibodies which recognize the enzyme in immunoblots. Epitope mapping using truncated forms of PAP and cyanogen bromide cleavage products revealed two classes of antibodies. One class (N-term) recognizes an epitope in the first 100 amino acids, and a second class (C-term) is specific for a determinant located in the last 20 amino acids of PAP. These C-terminal 20 amino acids can be removed without affecting the nonspecific poly(A) addition activity of the purified enzyme. Neither antibody inhibits the nonspecific poly(A) polymerase activity or the sequence-specific activity observed in processing extracts. The antibodies show species specificity and cannot recognize mammalian, Xenopus, or vaccinia PAP. The C-term antibodies can deplete PAP from yeast whole cell extracts, resulting in loss of poly(A) addition activity. This immunodepletion also causes a reduction in the cleavage activity which can be restored by addition of yeast cleavage factor I [CF I; Chen, J., & Moore, C. (1992) Mol. Cell Biol. 12, 3470-3481], a factor needed for both the cleavage and poly(A) addition reactions. This demonstrates that a complex of PAP and CF I exists in extracts in the absence of ATP or exogenous RNA substrate. The monoclonal antibodies against yeast PAP will be a useful tool for further study of factors required for yeast mRNA 3' end processing.

Antibodies, Monoclonal↗

PubMed1995

Photochemistry of type I acid-soluble calf skin collagen: dependence on excitation wavelength.

Although previous studies have demonstrated that the predominant photochemistry of type I collagen under 254 nm irradiation may be attributed either to direct absorption by tyrosine/phenylalanine or to peptide bonds, direct collagen photochemistry via solar UV wavelengths is much more likely to involve several age- and tissue-related photolabile collagen fluorophores that absorb in the latter region. In this study, we compare and contrast results obtained from irradiation of a commercial preparation of acid-soluble calf skin type I collagen in solution with UVC (primarily 254 nm), UVA (335-400 nm) and broad-band solar-simulating radiation (SSR; 290-400 nm). Excitation spectroscopy and analysis of photochemically induced disappearance of fluorescence (fluorescence fading) indicates that this preparation has at least four photolabile fluorescent chromophores. In addition to tyrosine and L-3,4-dihydroxyphenylalanine, our sample contains two other fluorophores. Chromophore I, with emission maximum at 360 nm, appears to be derived from interacting aromatic moieties in close mutual proximity. Chromophore II, with broad emission at 430-435 nm, may be composed of one or more age-related molecules. Collagen fluorescence fading kinetics are sensitive to excitation wavelength and to conformation. Under UVC, chromophore I fluorescence disappears with second-order kinetics, indicating a reaction between two proximal like molecules. Adherence to second-order kinetics is abrogated by prior denaturation of the collagen sample. A new broad, weak fluorescence band at 400-420 nm, attributable to dityrosine, forms under UVC, but not under solar radiation. This band is photolabile to UVA and UVB wavelengths.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Overexpression of human DNA topoisomerase I in insect cells using a baculovirus vector.

The 3645-bp human DNA topoisomerase I cDNA isolated by D'Arpa et al. (Proc. Natl. Acad. Sci. USA 85, 1988, 2543-2547) was integrated into the Autographa californica multiple nuclear polyhedrosis virus genome. The recombinant protein was expressed by infecting the SF9 insect cell line with this baculovirus and resulted in a 100-fold overexpression of human DNA topoisomerase I compared to the level found in human cell lines. This 100-kDa recombinant protein has the same electrophoretic mobility as the human DNA topoisomerase I from HeLa cells and is recognized by topoisomerase I-specific monoclonal antibody. The recombinant DNA topoisomerase I was isolated and purified to homogeneity with a two-step fractionation protocol and has a specific activity of 2 x 10(6) U/mg. Enzymatic properties such as stimulation by magnesium and inhibition by camptothecin resemble properties of the enzyme purified from human cell lines.

Animals↗

PubMed1993

Termination and pausing of RNA polymerase II downstream of yeast polyadenylation sites.

Little is known about the transcriptional events which occur downstream of polyadenylation sites. Although the polyadenylation site of a gene can be easily identified, it has been difficult to determine the site of transcription termination in vivo because of the rapid processing of pre-mRNAs. Using an in vitro approach, we have shown that sequences from the 3' ends of two different Saccharomyces cerevisiae genes, ADH2 and GAL7, direct transcription termination and/or polymerase pausing in yeast nuclear extracts. In the case of the ADH2 sequence, the RNA synthesized in vitro ends approximately 50 to 150 nucleotides downstream of the poly(A) site. This RNA is not polyadenylated and may represent the primary transcript. A similarly sized nonpolyadenylated [poly(A)-] transcript can be detected in vivo from the same transcriptional template. A GAL7 template also directs the in vitro synthesis of an RNA which extends a short distance past the poly(A) site. However, a significant amount of the GAL7 RNA is polyadenylated at or close to the in vivo poly(A) site. Mutations of GAL7 or ADH2 poly(A) signals prevent polyadenylation but do not affect the in vitro synthesis of the extended poly(A)- transcript. Since transcription of the mutant template continues through this region in vivo, it is likely that a strong RNA polymerase II pause site lies within the 3'-end sequences. Our data support the hypothesis that the coupling of this pause site to a functional polyadenylation signal results in transcription termination.

Cell-Free System↗

PubMed1992

Maternal stimulation affects the number of motor neurons in a sexually dimorphic nucleus of the lumbar spinal cord.

The role of maternal stimulation in the development of a lumbar motor nucleus (spinal nucleus of the bulboca vernosus, SNB) was investigated. The perineum, which has afferents to the lumbar region, is stimulated throughout early development by maternal licking, a behavior that is elicited by chemosignals secreted by the pups. In the present study, half of the dams were treated with intranasal zinc sulfate throughout the postpartum period, which led to a specific reduction in maternal stimulation of pup perineum by interfering with the reception of eliciting signals. Adult offspring of both sexes from anosmic dams had 11% fewer SNB motor neurons than normally stimulated controls, an effect which was most apparent in the rostral portion of the nucleus. There was no effect of treatment on neuron size. It was concluded that afferent input provided by species-typical maternal behavior contributes to the number of neurons that survive the neonatal period of normal cell death.

Animals↗

PubMed1992

Variation in maternal care and individual differences in play, exploration, and grooming of juvenile Norway rat offspring.

Individual differences in two different forms of maternal licking, time in nest and nursing, were measured during the first 2 weeks after birth. Two treatments were imposed to reduce maternal anogenital licking (AGL): peripheral zinc sulfate to interfere with reception of pup chemosignals, and dietary saline to reduce appetite for pup urine. Both treatments reduced AGL but did not affect other maternal licking. Zinc sulfate was more effective than saline during the first week, but was somewhat less selective as it also increased time in nest. Selected behavioral patterns were measured in male and female juveniles and related by multiple regression to the behavior of their mothers. Independent of the method of manipulation, maternal AGL was a significant predictor of play and open-field defecation males and of some forms of activity in the open field in both sexes. The relationships between other maternal variables and juvenile behavior were more modest. These data demonstrate that intervening in the sensory regulation of maternal behavior can produce predictable changes in stimulation provided by the dam, thereby providing a useful means for investigating the effects of protracted differences in early stimulation in otherwise normal developmental contexts.

Animals↗