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J M McGrath

Publications and source records attributed to J M McGrath.

At least 19 recordsLinked to original sources
PubMed2005

Development and characterization of potato-Solanum brevidens chromosomal addition/substitution lines.

Solanum brevidens is a wild diploid potato species possessing high levels of resistances to several major potato diseases. We previously developed fertile somatic hybrids between S. brevidens and the cultivated potato (Solanum tuberosum) in order to introgress disease resistances from this wild species into potato. A series of backcross progenies was developed from a hexaploid somatic hybrid A206. Using a combination of S. brevidens-specific randomly amplified polymorphic DNA (RAPD) markers and a sequential genomic in situ hybridization (GISH) and fluorescence in situ hybridization (FISH) technique, we identified all 12 S. brevidens chromosomes in the backcross progenies. Seven potato-S. brevidens monosomic chromosome addition lines (chromosomes 1, 3, 4, 5, 8, 9 and 10) and one monosomic substitution line (chromosome 6) were identified, and the remaining four S. brevidens chromosomes (2, 7, 11, and 12) were included in two other lines. These chromosomal addition/substitution stocks provide valuable tools for potato cytogenetic research, and can be used to introgress disease resistances from S. brevidens into potato.

Chromosomes, Plant↗
PubMed2003

Differential induction of glyoxylate cycle enzymes by stress as a marker for seedling vigor in sugar beet (Beta vulgaris).

Significant differences in seedling vigor exist among sugar beet (Beta vulgaris) hybrids; however, traditional approaches to breeding enhanced vigor have not proven effective. Seedling vigor is a complex character, but presumably includes efficient mobilization of seed storage reserves during germination and efficient seedling growth in diverse environments. The involvement of lipid metabolism during germination of sugar beet under stress conditions was suggested by the isolation at high frequency of Expressed Sequence Tags (ESTs) with similarity to isocitrate lyase (EC 4.1.3.1). High-level expression of this glyoxylate cycle enzyme during germination and seedling emergence was also suggested by nucleotide sequencing of cDNA libraries obtained from a well emerging sugar beet hybrid during germination under stress. Genes involved in carbohydrate and lipid catabolism were differentially expressed in a strongly emerging hybrid, relative to a weakly emerging hybrid, during stress germination. Stress markedly reduced the levels of alpha-amylase transcripts in the weakly emerging hybrid. In contrast, the strongly emerging hybrid exhibited only a moderate reduction in alpha-amylase transcript levels under the same conditions, and showed large increases in the expression of genes involved in lipid metabolism, suggesting compensation by lipid for carbohydrate metabolism in the better emerging hybrid. Differential activity of the glyoxylate cycle thus appears to be a physiological marker that distinguishes between high- and low-vigor sugar beet cultivars. This finding suggests, for the first time, a biochemical target for selection for enhanced germination and improved emergence in sugar beet.

Beta vulgaris↗
PubMed2003

A snapshot of the low temperature stress transcriptome of developing rice seedlings (Oryza sativa L.) via ESTs from subtracted cDNA library.

Rice (Oryza sativa L.) is sensitive to chilling particularly during early seedling development. Given the biochemical complexity of tolerance mechanisms, genetic potential for this trait depends on highly coordinated expression of many genes. We used a simple cDNA subtraction strategy to develop Expressed Sequence Tags (ESTs) that represent an important subset of cold stress-upregulated genes. The 3,084 subtracted cDNA clones represent a total of 1,967 unigenes from 1,354 singletons and 613 contigs. As expected in the developing seedlings, genes involved in basic cellular processes, i.e., metabolism, growth and development, protein synthesis, folding and destination, cellular transport, cell division and DNA replication were widely represented. Genes with stress-related and regulatory functions comprised 23.17% of the total ESTs. These categories included proteins with known function in cellular defenses against abiotic (drought, cold and salinity) and biotic (pathogen) stresses, and proteins involved in developmental and stress response signalling and transcription. Based on the types of genes represented, tolerance mechanisms rely on precise integration of developmental processes with stress-related responses. A large fraction of the ESTs (38.7%) represents unknown proteins. This EST library is a rich source of cold stress-related genes, and supplements for other publicly available libraries for comprehensive analysis of the stress-response transcriptome.

Cold Temperature↗
PubMed2003

Risk factors as the basis for triage in low-resource cervical cancer screening programs.

OBJECTIVES: Several studies have shown impressive sensitivity and specificity of visual inspection using acetic acid wash (VIA) in detecting cervical dysplasia. This study examines how risk-factor based triage, using clinical history-taking to limit the testing to those at highest risk of disease, improves the clinical utility of VIA. METHODS: The study population included 2206 woman aged 25-56 from peri-urban primary care clinics in Zimbabwe. Three risk factors variables [age, lifetime number of sexual partners and history of a sexually transmitted infection (STI)] were selected as the basis for computer-simulated patient triage. Criteria for selecting risk factors were biological relevance, programmatic feasibility, historical evidence in the scientific literature as a risk factor for cervical cancer and a significant (P<0.05) predictor of dysplasia in this study population. Predictive values for VIA were calculated on subgroups of women with combinations of the three risk factors and then compared with the predictive value of VIA calculated on the full study population. RESULTS: The positive predictive value (PPV) among women with all three risk factors (30.2%) was 1.6 times higher than that of all study women and 4.5 times higher than women with none of the three risk factors (4.1%). Additionally, the PPV was slightly (30%) higher than that obtained from computer-simulated serial testing using VIA as the primary test followed by HPV testing (27.4%). CONCLUSION: Clinical history-taking could provide the basis for patient triage to increase the clinical utility of VIA. Such an approach could also serve to prioritize who gets tested first in low-resource countries with high disease prevalence that are struggling to strengthen national cervical cancer prevention programs.

Acetic Acid↗
PubMed2001

Analysis of the introgression of Solanum bulbocastanum DNA into potato breeding lines.

Somatic hybrids have been obtained between potato and Solanum bulbocastanum PI 245310, a Mexican diploid (2n=2x=24) species. Through restriction fragment length polymorphism (RFLP) and randomly amplified polymorphic DNA (RAPD) analyses it was found that the somatic hybrids contain each chromosome of the diploid parent and that the synteny of RFLP markers noted with tomato, potato and S. brevidens is largely maintained in S. bulbocastanum. RFLP analyses of BC1 progeny of two different hybrids indicated that a substantial number of markers were either lost or were heterozygous, in marked contrast with results previously noted with S. brevidens. A RAPD map for all 12 chromosomes of S. bulbocastanum was prepared and marker transmission was followed in three BC2 populations. Results with chromosomes 3, 8 and 10 from these populations are compared.

Chromosome Mapping↗
PubMed2001

Building relationships with families in the NICU: exploring the guarded alliance.

Extremely low-birthweight infants and their families experience prolonged hospitalization in the newborn intensive care unit (NICU). Prolonged hospitalization is particularly stressful for the family, leading to distress in most aspects of their lives, including separation of parents from each other and from other family members, a need for increased psychological support, and increased economic concerns. Based on these characteristics, these families appear to have needs more similar to that of families caring for chronically ill members. Indeed, this initial hospitalization may be the prelude to coping and surviving with a chronic illness for many of these children and families. This article proposes the adaption of "guarded alliance" as a framework for developing relationships and providing care to families in the NICU. This framework was derived from research with families of the chronically ill. Supportive research is used to justify the adoption of this framework for interactions with families in the NICU. In addition, linkages to family-centered care principles in critical care settings are also discussed.

Adaptation, Psychological↗
PubMed2001

The genetic identity of alien chromosomes in potato breeding lines revealed by sequential GISH and FISH analyses using chromosome-specific cytogenetic DNA markers.

Genomic in situ hybridization (GISH) is one of the most popular and effective techniques for detecting alien chromatin introgressed into breeding lines; however, GISH analysis alone does not reveal the genetic identity of the alien chromosomes. We previously isolated a set of bacterial artificial chromosomes (BACs) specific to each of the 12 potato chromosomes. These BAC clones can be used as chromosome-specific cytogenetic DNA markers (CSCDMs) for potato chromosome identification. Here we demonstrate that GISH and fluorescence in situ hybridization (FISH), using CSCDMs, can be performed sequentially on the same chromosome preparations. Somatic metaphase chromosomes prepared using an enzymatic digestion and "flame-drying" procedure allows repeated probing up to five times without significant damage to chromosome morphology. The sequential GISH and FISH analyses reveal the genomic origin and genetic identity of the alien chromosomes in a single experiment and also determine whether an alien chromosome has been added to the genetic background of potato or is substituting for a homoeologous potato chromosome. The sequential GISH and FISH procedures should be widely applicable for germplasm characterization, especially in plant species with small-sized chromosomes.

Chromosomes↗
PubMed2000

Developmentally supportive caregiving and technology in the NICU: isolation or merger of intervention strategies?

Providing nursing care in the highly technical environment of the neonatal intensive care unit is changing as concepts of developmentally supportive caregiving merge with conventional nursing interventions and are integrated into routine practice. Medical knowledge with the use of technology is insufficient in guiding the whole of neonatal nursing care. Integration of other patterns and concepts is essential to expert nursing practice with high risk infants and their families.

Humans↗
PubMed1999

Physicians' perspectives on communicating prescription drug information.

Physician-patient communication has been identified as one factor that influences prescription drug compliance rates, even though the nature of such communication has not been well described. This study used a qualitative approach (in-depth interviews with 20 physicians representing a variety of medical areas) to better understand the process by which physicians communicate prescription drug information to their patients. A content analysis of interview transcripts indicated that two-way interactions focusing on the specific needs of the patients should be encouraged over simply disseminating more and more information about prescriptions. Information regarding unlikely outcomes was suggested to cause patient anxiety, which might be tied to decreased compliance rates. Physicians stressed the importance of "patient-directed communication" and expressed their concern over what they considered to be inappropriate sources of drug information. Other specific reasons cited for noncompliance included forgetfulness, ignoring medication when feeling better, and apprehensions about side effects.

Attitude of Health Personnel↗
PubMed1997

Methylation of somatic and sperm DNA in the homosporous fern Ceratopteris richardii.

Plants, in general, have a high proportion of their CpG and CpNpG nucleotide motifs modified with 5-methylcytosine (5mC). Developmental changes in the proportion of 5mC are evident in mammals, particularly during gametogenesis and embryogenesis, but little information is available from flowering plants due to the intimate association of gametes with sporophytic tissues. In ferns, sperm are uninucleate and free-swimming and thus are easily isolated. We have examined 5mC in DNA isolated from fern sperm and other tissues with methylation-sensitive and -insensitive restriction enzyme isoschizomers, Southern blots probed with chloroplast and nuclear ribosomal RNA genes and end-labeled restriction fragments. We conclude that fern sperm DNA is methylated to a similar or greater degree than DNA isolated from either sporophytes or gametophytes.

Chloroplasts↗
PubMed1996

Segregation and recombination of Solanum brevidens synteny groups in progeny of somatic hybrids with S. tuberosum: intragenomic equals or exceeds intergenomic recombination.

The Solanum brevidens genome (2n = 2x = 24) was examined with randomly applied polymorphic DNA (RAPD) markers in a second backcross population derived from a S. brevidens + S. tuberosum somatic hybrid. RAPD markers cosegregated into 12 different S. brevidens synteny groups. Most synteny groups were nonrecombinant. However, nearly 40% of the S. brevidens synteny groups detected in this population were recombinant deletions that carried at least one, but not all, synteny group-specific RAPD markers. All S. brevidens synteny groups (except chromosome 5) were involved in recombination, and recombination occurred within most intervals between markers. About 20% of the recombinant S. brevidens synteny groups involved a single synteny group-specific marker. The inheritance of some single-marker representatives was followed in four BC3 families. At least nine changes in S. brevidens synteny groups had occurred during backcrossing. Six of the nine changes involved translocation of S. brevidens markers between nonhomologous S. brevidens chromosomes, and three S. brevidens markers may have been introgressed into the potato genome.

Genome, Plant↗
PubMed1996

Integrating family-centered developmental assessment and intervention into routine care in the neonatal intensive care unit.

Incorporating developmental intervention into routine practices requires time available during caregiving for continued infant assessment and intervention and requires time after and between caregiving for relief of infant distress. In an era of health-care reform, reorganization, and restructuring, this added caregiver time appears unavailable. However, nurses need to work together in meeting the developmental challenges of the NICU. Further research needs to be done to validate which interventions are appropriate for which babies and with what medical procedures. In addition, collaboration and sharing of responsibilities and resources with all care providers needs to be investigated. Moreover, research needs to be done that acknowledges that the environment of the NICU is also a world in which many adults work and live a large portion of their daily life. This environment must be supportive of their social needs as well as the needs of the high-risk infant. There are many pieces to the puzzle of providing developmentally supportive caregiving in the NICU. The number of different issues increases the complexity of changing the standard of care: Infant, family, environment. Each has its own challenges. However, with sensitivity, a collaborative approach, and a sincere effort to change, neonatal health-care professionals can integrate developmental practices into the NICU.

Child Development↗
PubMed1996

Implementing a research-based kangaroo care program in the NICU.

Kangaroo care or skin-to-skin holding of preterm infants requires consistent implementation for best outcomes with infants and families. Successful implementation of a project of this type demands an organized approach. This article describes how a standard of care was developed using research findings and then implemented with a step-by-step approach in the neonatal intensive care unit.

Arizona↗
PubMed1995

An evaluation of the effect of anesthetic technique on reproductive success after laparoscopic pronuclear stage transfer. Propofol/nitrous oxide versus isoflurane/nitrous oxide.

BACKGROUND: Laparoscopic pronuclear stage transfer (PROST) is the preferred method of embryo transfer after in vitro fertilization in many infertility programs. There are scant data to recommend the use or avoidance of any particular anesthetic agent for use in women undergoing this procedure. The authors hypothesized that propofol would be an ideal anesthetic for laparoscopic PROST because of its characteristic favorable recovery profile that includes minimal sedation and a low incidence of postoperative nausea and vomiting. The purpose of the study was to compare propofol and isoflurance with respect to postanesthetic recovery and pregnancy outcomes after laparoscopic PROST. METHODS: One hundred twelve women scheduled for laparoscopic PROST were randomized to receive either propofol/nitrous oxide or isoflurane/nitrous oxide for maintenance of anesthesia. RESULTS: Visual analog scale scores for sedation were lower in the propofol group than in the isoflurance group at all measurements between 30 min and 3 h after surgery. More women experienced emesis and were given an antiemetic during recovery in the isoflurance group than in the propofol group. However, the percentage of pregnancies with evidence of fetal cardiac activity was 54% in the isoflurane group compared with only 30% in the propofol group (P = 0.023). Also, the ongoing pregnancy rate was greater in the isoflurane group than in the propofol group (54% vs. 29%, P = 0.014). CONCLUSIONS: Propofol/nitrous oxide anesthesia was associated with lower clinical and ongoing pregnancy rates compared with isoflurane/nitrous oxide anesthesia.

Adult↗
PubMed1994

Ephedrine remains the vasopressor of choice for treatment of hypotension during ritodrine infusion and epidural anesthesia.

BACKGROUND: Historically, ephedrine has been the vasopressor of choice for treatment of most cases of hypotension in obstetric patients. However, the choice of vasopressor in the parturient receiving a beta-adrenergic agent for tocolysis has not been evaluated extensively. The current study evaluated whether ephedrine or phenylephrine better restores uterine blood flow and fetal oxygenation during ritodrine infusion and epidural anesthesia-induced hypotension in gravid ewes. METHODS: Fourteen chronically instrumented gravid ewes between 0.8 and 0.9 timed gestational age were used. On separate days, each animal underwent the experimental protocol with one of three agents: ephedrine, phenylephrine, and normal saline-control. The experimental protocol was as follows: (1) at time zero, intravenous infusion of ritodrine was begun; (2) at 120 min, 2% lidocaine was given epidurally to achieve a sensory level of at least T6; and (3) at 135 min, an intravenous bolus of either ephedrine, phenylephrine, or normal saline-control was given, followed by a continuous intravenous infusion of the same agent for 30 min. In the ephedrine and phenylephrine experiments, the rate of infusion was adjusted to maintain maternal mean arterial pressure close to baseline. RESULTS: Ritodrine infusion alone significantly increased maternal heart rate and cardiac output in all three groups. Epidural anesthesia during ritodrine infusion significantly decreased maternal mean arterial pressure, heart rate, cardiac output, uterine blood flow, and fetal arterial oxygen tension for each of the three groups. Both ephedrine and phenylephrine restored maternal mean arterial pressure to baseline, as designed. Ephedrine significantly increased uterine blood flow and fetal arterial oxygen tension when compared with normal saline--control, but phenylephrine did not. Phenylephrine significantly increased uterine vascular resistance when compared with normal saline--control, but ephedrine did not. CONCLUSIONS: Although ephedrine and phenylephrine provided similar restoration of maternal mean arterial pressure, ephedrine was superior to phenylephrine in restoring uterine blood flow during ritodrine infusion and epidural anesthesia-induced hypotension in gravid ewes. Also, ephedrine, but not phenylephrine, significantly improved fetal oxygenation, when compared to normal saline--control.

Acid-Base Equilibrium↗
PubMed1994

Does early administration of epidural analgesia affect obstetric outcome in nulliparous women who are receiving intravenous oxytocin?

BACKGROUND: Some studies suggest that epidural analgesia prolongs labor and increases the incidence of cesarean section, especially if it is administered before 5 cm cervical dilation. The purpose of the current study was to determine whether early administration of epidural analgesia affects obstetric outcome in nulliparous women who are receiving intravenous oxytocin. METHODS: Informed consent was obtained from healthy nulliparous women with a singleton fetus in a vertex presentation, who requested epidural analgesia while receiving intravenous oxytocin at at least 36 weeks' gestation. Each patient was randomized to receive either early or late epidural analgesia. Randomization occurred only after the following conditions were met: (1) the patient requested pain relief at that moment, (2) a lumbar epidural catheter had been placed, and (3) the cervix was at least 3 but less than 5 cm dilated. Patients in the early group immediately received epidural bupivacaine analgesia. Patients in the late group received 10 mg nalbuphine intravenously. Late-group patients did not receive epidural analgesia until they achieved a cervical dilation of at least 5 cm or until at least 1 h had elapsed after a second dose of nalbuphine. RESULTS: Early administration of epidural analgesia did not prolong the interval between randomization and the diagnosis of complete cervical dilation, and it did not increase the incidence of malposition of the vertex at delivery. Also, early administration of epidural analgesia did not result in an increased incidence of cesarean section or instrumental vaginal delivery. Thirteen (18%) of 74 women in the early group and 14 (19%) of 75 women in the late group underwent cesarean section (relative risk for the early group 0.94; 95% confidence interval 0.48-1.84). Patients in the early group had lower pain scores between 30 and 120 min after randomization, and were more likely to experience transient hypotension. Infants in the late group had lower umbilical arterial and venous blood pH and higher umbilical arterial and venous blood carbon dioxide tension measurements at delivery. CONCLUSIONS: Early administration of epidural analgesia did not prolong labor or increase the incidence of operative delivery, when compared with intravenous nalbuphine followed by late administration of epidural analgesia, in nulliparous women who were receiving intravenous oxytocin.

Adult↗
PubMed1994

Does early administration of epidural analgesia affect obstetric outcome in nulliparous women who are in spontaneous labor?

BACKGROUND: Some studies suggest that epidural analgesia prolongs labor and increases the incidence of cesarean section, especially if it is administered before 5 cm cervical dilation. The purpose of the current study was to determine whether early administration of epidural analgesia affects obstetric outcome in nulliparous women who are in spontaneous labor. METHODS: Informed consent was obtained from 344 healthy nulliparous women with a singleton fetus in a vertex presentation, who requested epidural analgesia during spontaneous labor at at least 36 weeks' gestation. Each patient was randomized to receive either early or late epidural analgesia. Randomization occurred only after the following conditions were met: (1) the patient requested pain relief at that moment, (2) a lumbar epidural catheter had been placed, and (3) the cervix was at least 3 cm but less than 5 cm dilated. Patients in the early group immediately received epidural bupivacaine analgesia. Patients in the late group received 10 mg nalbuphine intravenously. Late-group patients did not receive epidural analgesia until they achieved a cervical dilation of at least 5 cm or until at least 1 h had elapsed after a second dose of nalbuphine. Ten of the 344 patients were excluded because of a protocol violation or voluntary withdrawal from the study. RESULTS: Early administration of epidural analgesia did not increase the incidence of oxytocin augmentation, prolong the interval between randomization and the diagnosis of complete cervical dilation, or increase the incidence of malposition of the vertex at delivery. Also, early administration of epidural analgesia did not result in an increased incidence of cesarean section or instrumental vaginal delivery. Seventeen (10%) of 172 women in the early group and 13 (8%) of 162 women in the late group underwent cesarean section (relative risk for the early group 1.22; 95% confidence interval 0.62-2.40). Patients in the early group had lower pain scores between 30 and 150 min after randomization. Infants in the late group had lower umbilical arterial and venous blood pH and higher umbilical venous blood carbon dioxide tension measurements at delivery. CONCLUSIONS: Early administration of epidural analgesia did not prolong labor, increase the incidence of oxytocin augmentation, or increase the incidence of operative delivery, when compared with intravenous nalbuphine followed by late administration of epidural analgesia, in nulliparous women who were in spontaneous labor at term.

Adult↗