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N Ellison

Publications and source records attributed to N Ellison.

At least 19 recordsLinked to original sources
PubMed2004

A microsatellite map of white clover.

The white clover ( Trifolium repens) nuclear genome (n = 2x = 16) is an important yet under-characterised genetic environment. We have developed simple sequence repeat (SSR) genetic markers for the white clover genome by mining an expressed sequence tag (EST) database and by isolation from enriched genomic libraries. A total of 2,086 EST-derived SSRs (EST-SSRs) were identified among 26,480 database accessions. Evaluation of 792 EST-SSR primer pairs resulted in 566 usable EST-SSRs. Of these, 335 polymorphic EST-SSRs, used in concert with 30 genomic SSRs, detected 493 loci in the white clover genome using 92 F1 progeny from a pair cross between two highly heterozygous genotypes--364/7 and 6525/5. Map length, as estimated using the joinmap algorithm, was 1,144 cM and spanned all 16 homologues. The R (red leaf) locus was mapped to linkage group B1 and is tightly linked to the microsatellite locus prs318c. The eight homoeologous pairs of linkage groups within the white clover genome were identified using 96 homoeologous loci. Segregation distortion was detected in four areas (groups A1, D1, D2 and H2). Marker locus density varied among and within linkage groups. This is the first time EST-SSRs have been used to build a whole-genome functional map and to describe subgenome organisation in an allopolyploid species, and T. repens is the only Trifolieae species to date to be mapped exclusively with SSRs. This gene-based microsatellite map will enable the resolution of quantitative traits into Mendelian characters, the characterisation of syntenic relationships with other genomes and acceleration of white clover improvement programmes.

Chromosome Mapping↗
PubMed2001

Red blood cells: an analysis of risk versus benefit.

The value of red blood cell administration to increase oxygen carrying capacity is obvious to all clinicians. Nevertheless, there has never been a prospective, randomized, controlled study documenting the efficacy or conclusively defining the indications for red blood cell use. Considering the risks associated with allogeneic blood, careful consideration must be given before the administration of each unit of blood product.

Blood Transfusion↗
PubMed2000

An alternative algorithm for dosing transdermal fentanyl for cancer-related pain.

Many cancer patients are undermedicated and inappropriately managed for pain, leading to a diminished quality of life. Patients with moderate to severe pain often require opioid analgesics. Recently published guidelines emphasize individualization of opioid treatment to provide the drug and route of administration that meet the needs of the particular patient. Intolerable side effects, ineffective pain relief, or a change in the patient's clinical status can dictate the need for a new pain management regimen. Physicians must be able to readily quantify relative analgesic potency when converting from one opioid to another or from one route of administration to another. Transdermal fentanyl (Duragesic) is an opioid agonist that has been shown to be safe and effective for the treatment of cancer pain. However, clinicians should realize that the manufacturer's recommendations for equianalgesic dosing of transdermal fentanyl may result in initial doses that are too low in some patients, and in a titration period that is too long. Under these circumstances, the patient is likely to experience unrelieved pain. An alternative dosing algorithm that considers both a review of the literature and our combined clinical experience with transdermal fentanyl should help clinicians individualize the treatment of pain.

Administration, Cutaneous↗
PubMed1998

Risk factors for clinically important adverse events after protamine administration following cardiopulmonary bypass.

OBJECTIVES: The purpose of this study was to determine risk factors for adverse events following protamine administration after cardiopulmonary bypass. BACKGROUND: Intravenous protamine administration is associated with a risk of severe systemic reactions. However, risk factors for these events have not been well delineated, thus hampering development of preventive strategies. METHODS: A case-control study nested within a cohort of consecutive patients undergoing surgery requiring cardiopulmonary bypass was performed. The primary case definition included those events (pulmonary hypertensive and systemic hypotensive) occurring within 10 min of protamine administration in the absence of other measurable causes of hemodynamic compromise. RESULTS: Comparing the 53 cases to the 223 control subjects, three risk factors were independently associated with events (multivariable odds ratio [95% confidence interval]): neutral protamine Hagedorn insulin use (8.18 [2.08, 32.2]); fish allergy (24.5 [1.24, 482.3]), and a history of nonprotamine medication allergy (2.97 [1.25, 7.07]). These risk factors demonstrated an increasingly strong association with progressively more specific case definitions. An estimated 39% of cardiopulmonary bypass patients had one or more of these risk factors. Prior intravenous protamine, central venous pressure prior to protamine, preoperative ejection fraction and the need for inotropes when coming off bypass did not exhibit statistically significant associations with events (all p > 0.15). Prior protamine allergy was associated specifically with an increased risk of pulmonary hypertension (multivariable odds ratio 189; 95% confidence interval 13, 2,856). CONCLUSIONS: Immunologic factors are important in predisposing individuals to protamine reactions, and a substantial proportion of patients are at considerably increased risk Strategies to reduce the risk of protamine-associated events are needed.

Cardiopulmonary Bypass↗
PubMed1997

Phase III randomized double-blind study to evaluate the efficacy of a polycarbophil-based vaginal moisturizer in women with breast cancer.

PURPOSE: Vaginal dryness and dyspareunia are significant estrogen-depletion symptoms that affect many breast cancer survivors. The present trial was developed to evaluate the nonhormonal vaginal lubricating preparation, Replens, for alleviating these symptoms. MATERIALS AND METHODS: A double-blind, crossover, randomized clinical trial was developed. Patients received 4 weeks of Replens (Columbia Research Laboratories, Rockville Centre, NY) followed by a 1-week washout period followed by 4 weeks of a placebo lubricating product, or vice versa. Weekly patient-completed diaries were used for measuring efficacies and toxicities of therapy. RESULTS: The 45 assessable patients provided well-balanced treatment groups. During the first 4 weeks, average vaginal dryness decreased by 62% and 64% in the placebo and Replens groups, respectively (P = .3). Average dyspareunia scores also improved by 41% and 60%, respectively (P = .05). Crossover analysis indicated that the bulk of the beneficial effects appeared within the first 2 weeks of the first treatment and remained constant thereafter. Both treatments were relatively well tolerated. CONCLUSION: Both Replens and the placebo appear to substantially ameliorate vaginal dryness and dyspareunia in breast cancer survivors.

Adult↗
PubMed1997

Phase III placebo-controlled trial of capsaicin cream in the management of surgical neuropathic pain in cancer patients.

PURPOSE: A minority of cancer survivors develops long-term postsurgical neuropathic pain. Based on evidence that capsaicin, the pungent ingredient in hot chili peppers, might be useful for treating neuropathic pain, we developed the present clinical trial. PATIENTS AND METHODS: Ninety-nine assessable patients with postsurgical neuropathic pain were entered onto this study. After stratification, patients were to receive 8 weeks of a 0.075% capsaicin cream followed by 8 weeks of an identical-appearing placebo cream, or vice versa. A capsaicin/placebo cream was to be applied to the painful site four times daily. Treatment evaluation was performed by patient-completed weekly questionnaires. RESULTS: During the first 8-week study period, the capsaicin-cream arm was associated with substantially more skin burning, skin redness, and coughing (P < .0001 for each). Nonetheless, treatment was stopped for patient refusal or toxicity just as often while patients were receiving the placebo as compared with the capsaicin. The capsaicin cream arm had substantially more pain relief (P = .01) after the first 8 weeks, with an average pain reduction of 53% versus 17%. On completion of the 16-week study period, patients were asked which treatment period was most beneficial. Of the responding patients, 60% chose the capsaicin arm, 18% chose the placebo arm, and 22% chose neither (P = .001). CONCLUSION: A topical capsaicin cream decreases postsurgical neuropathic pain and, despite some toxicities, is preferred by patients over a placebo by a three-to-one margin among those expressing a preference.

Administration, Topical↗
PubMed1990

Direct detection of activated platelets and platelet-derived microparticles in humans.

Flow cytometry was used to determine whether activated platelets and platelet-derived microparticles can be detected directly in whole blood after a hemostatic insult. Two different in vivo models of platelet activation were examined: (1) a standardized bleeding time, and (2) cardiopulmonary bypass. Platelets and microplatelets were identified with a biotinylated anti-glycoprotein (GP)lb antibody and a fluorophore, phycoerythrin-streptavidin. Microparticles were distinguished from platelets by light scatter. Activated platelets were detected with three fluorescein-labeled monoclonal antibodies (MoAbs): (1) PAC1, which binds to the activated form of GPIIb-IIIa; (2) 9F9, a newly developed antibody that is specific for fibrinogen bound to the surface of activated platelets; and (3) S12, which binds to an alpha-granule membrane protein expressed on the platelet surface after granule secretion. In nine normal subjects, bleeding times ranged from 4.5 to 7.5 minutes. Over this time, there was a progressive increase in the amount of PAC1, 9F9, and S12 bound to platelets in blood emerging from the bleeding time wound. With all three antibodies, platelet activation was apparent as early as 30 seconds after the incision (P less than .03). Activation was accompanied by a progressive decrease in the concentration of platelets in blood from the wound, while the concentration of microparticles increased slightly. In nine patients undergoing open heart surgery, 1 hour of cardiopulmonary bypass caused a 2.2-fold increase in the relative proportion of microparticles in circulating blood (P less than .001). Moreover, bypass caused platelet activation as evidenced by a mean two- to threefold increase in PAC1 binding to platelets. Although this increase was significant (P less than .02), PAC1 binding exceeded the normal range for unstimulated control platelets in only 5 of 9 patients, and 9F9 and S12 binding exceeded the normal range in only two patients. Taken together, these studies demonstrate that it is now feasible using flow cytometry to evaluate the extent of platelet activation and the presence of platelet-derived microparticles in the circulation of humans.

Adenosine Diphosphate↗