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G Constantine

Publications and source records attributed to G Constantine.

49 records · Page 3Linked to original sources

A review of boron neutron capture therapy (BNCT) and the design and dosimetry of a high-intensity, 24 keV, neutron beam for BNCT research.

This paper reviews the development of boron neutron capture therapy (BNCT) and describes the design and dosimetry of an intermediate energy neutron beam, developed at the Harwell Laboratory, principally for BNCT research. Boron neutron capture therapy is a technique for the treatment of gliomas (a fatal form of brain tumour). The technique involves preferentially attaching 10B atoms to tumour cells and irradiating them with thermal neutrons. The thermal neutron capture products of 10B are short range and highly damaging, so they kill the tumour cells, but healthy tissue is relatively undamaged. Early trials required extensive neurosurgery to exposure the tumour to the thermal neutrons used and were unsuccessful. It is thought that intermediate-energy neutrons will overcome many of the problems encountered in the early trials, because they have greater penetration prior to thermalization, so that surgery will not be required. An intermediate-energy neutron beam has been developed at the Harwell Laboratory for research into BNCT. Neutrons from the core of a high-flux nuclear reactor are filtered with a combination of iron, aluminium and sulphur. Dosimetry measurements have been made to determine the neutron and gamma-ray characteristics of this beam, and to monitor them throughout the four cycles used for BNCT research. The beam is of high intensity (approximately 2 x 10(7) neutrons cm-2 s-1, equivalent to a neutron kerma rate in water of 205 mGy h-1) and nearly monoenergetic (93% of the neutrons have energies approximately 24 keV, corresponding to 79% of the neutron kerma rate).

Boron↗

Vaginal absorption of naproxen.

The vaginal absorption of the drug naproxen was investigated in five healthy pre-menopausal women. It was found that naproxen was absorbed, but not to therapeutically useful levels.

Absorption↗

Nifedipine as a second line antihypertensive drug in pregnancy.

Slow-release nifedipine has been used in the treatment of severe hypertension in 23 pregnant women. In 22 this was in combination with other drugs, in 18 including atenolol. Good control of blood pressure was achieved in 20 women. The perinatal mortality of the group was 130/1000, with a high caesarean section rate (71% of live-births), a high rate of abnormal CTGs, a high rate of premature delivery, and a high rate of infants who were small-for-dates. Whether this is due to the disease process or the medication is uncertain. For the present time these combinations should only be used in severe hypertensives or in the context of a controlled trial.

Adult↗

Amoebic peritonitis in pregnancy in the United Kingdom.

We describe a woman who developed hepatic amoebic abscesses during pregnancy, and subsequently amoebic peritonitis. We believe this to be the first such recorded case in the United Kingdom, and unusual in that the patient had never been abroad.

Adult↗

Double-blind, placebo-controlled comparison of the safety and efficacy of orally administered etodolac and nabumetone in patients with active osteoarthritis of the knee.

This 4-week, randomized, double-blind, double-dummy, placebo-controlled, parallel-group, multicenter study was designed to compare the efficacy and safety of etodolac and nabumetone in the treatment of patients with active osteoarthritis (OA) of the knee. Ninety-one patients received etodolac 400 mg twice daily, 89 received nabumetone 1500 mg once daily, and 90 received placebo. Both active treatments significantly improved the patients' condition relative to baseline (P < or = 0.001) at all evaluations during treatment and relative to placebo (P < or = 0.05) by visit 4. Improvement relative to placebo in investigator's global assessments was earlier in the etodolac group (ie, by visit 3) than in the nabumetone group. At visit 4, improvement in investigator's and patient's global assessment scores, and in the distribution of investigator's assessment scores, was significantly (P < or = 0.05) greater in the etodolac group than in the nabumetone group. Other than hypokalemia, which occurred only in three patients in the nabumetone group (P = 0.035), there were no significant differences among the groups in the frequency of study events or premature discontinuation from the study as a result of study events. Study events considered at least possibly treatment related were reported for 26 patients in the etodolac group (28.6%), 20 in the nabumetone group (22.5%), and 23 in the placebo group (25.6%). The most frequently reported symptoms for all groups were dyspepsia, nausea, and headache. Four patients treated with nabumetone (4.5%) had elevations in aspartate aminotransferase or alanine aminotransferase during treatment. The results of this study show that etodolac 400 mg twice daily is at least as effective as nabumetone 1500 mg once daily and is equally well tolerated in the treatment of patients with active OA of the knee; etodolac may have an earlier onset of action and/or a relatively greater efficacy in patient and investigator global assessments than nabumetone.

Adult↗

Efficacy and safety of etodolac and naproxen in patients with osteoarthritis of the knee: a double-blind, placebo-controlled study.

A multicenter, parallel-group, double-blind, randomized, outpatient study compared the efficacy and safety of etodolac versus naproxen in patients with osteoarthritis of the knee. After a washout period free of nonsteroidal anti-inflammatory drugs, 254 patients self-administered etodolac 400 mg (n = 86), naproxen 500 mg (n = 82), or placebo (n = 86) twice daily for 4 weeks. Compliance exceeded 90% in all three groups. Primary efficacy variables improved progressively from baseline in all three groups. The extent of improvement was greater in the etodolac and naproxen groups than in the placebo group (P < or = 0.003), except with respect to target joint tenderness (P = 0.028, etodolac vs placebo; P = 0.013, naproxen vs placebo). There were no statistical differences between active treatment groups (P > 0.1). At end point, twice as many patients responded in the etodolac (59%) and naproxen groups (51%) than in the placebo group (26%; P < or = 0.01). There were no significant between-group differences in the numbers of patients who had an adverse experience, a serious adverse experience, or an adverse experience leading to study discontinuation; there were also no significant between-group differences in the distribution of adverse experiences. There were no unexpected clinical or laboratory experiences. Etodolac 400 mg twice daily was as effective and safe as naproxen 500 mg twice daily and both were superior to placebo in the management of osteoarthritis of the knee.

Anti-Inflammatory Agents, Non-Steroidal↗

A double-masked comparison of Naprelan and nabumetone in osteoarthritis of the knee. Naprelan Study Group.

The efficacy and safety of Naprelan (naproxen sodium) 1000 mg once daily (QD) and nabumetone 1500 mg QD were compared in a multicenter, randomized, parallel-group, placebo-controlled, double-masked, 4-week study of adult outpatients with active osteoarthritis (OA) of the knee. Nabumetone 1500 mg was chosen for comparison because it is commonly prescribed in a QD dosing regimen for OA. After a washout period free of nonsteroidal anti-inflammatory drugs, 279 patients were enrolled and assigned randomly to treatment with either Naprelan 1000 mg QD (n = 92), nabumetone 1500 mg QD (n = 93), or placebo (n = 94). All treatments were evaluated for efficacy and safety at baseline and at weeks 2 and 4 of the treatment period or at discontinuation. Demographic characteristics were comparable among all treatment groups. As might be expected in a study of OA of the knee, a majority of patients enrolled were women (68.8%), and many were obese (mean weight, 195.6 lb; mean height, 66 in). Significantly fewer patients (13) treated with Naprelan prematurely discontinued the study than did patients treated with placebo (27); there was a lower rate of discontinuation for insufficient therapeutic effect in the Naprelan group compared with the nabumetone and placebo groups. Using an intent-to-treat model, the overall distribution of scores in all three primary efficacy assessments (investigator's global assessment of OA, patient's global assessment of OA, and walking pain) at week 2 and at the last visit was significantly better for the Naprelan group compared with both the nabumetone and placebo groups. The mean improvement from baseline was also significant for Naprelan compared with the nabumetone and placebo groups for all three assessments at week 2 and for investigator's global assessment of OA and walking pain at the last visit. The nabumetone-treated group showed significant improvement over the placebo-treated group in only one primary assessment: mean change from baseline in patient's global assessment of OA at week 2. At week 2, significant differences favoring Naprelan versus nabumetone and placebo were measured in overall distribution of scores for joint tenderness and nighttime pain. Distribution of quality of sleep and inactivity stiffness scores also improved relative to placebo at week 2. At the last visit, nighttime pain scores were still significantly better for patients receiving Naprelan versus nabumetone and placebo. Patients receiving nabumetone had statistically significant improvement from baseline in inactivity stiffness compared with placebo at week 2. There were no clinically important differences among treatment groups in the occurrence of adverse events or laboratory abnormalities. The results of this 4-week study of Naprelan 1000 mg QD compared with nabumetone 1500 mg QD demonstrate at least equal efficacy (superior efficacy was demonstrated for several parameters) and equal safety in adult outpatients with active OA of the knee.

Adult↗