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C Giles

Publications and source records attributed to C Giles.

At least 37 records · Page 2Linked to original sources
PubMed1996

Design of an X-ray Phase-Plate Analyzer to Measure the Circular Polarization Rate of a Helical Undulator Source.

A quarter-wave plate made of a ca 16 mum-thick silicon single-crystal was used at energies as low as 2.8 keV to convert circularly polarized photons into linearly polarized photons. Coupled to a linear polarimeter, this quarter-wave plate enabled the characterization of the circular polarization rate of the radiation emitted by one of the ESRF helical undulators, Helios-I. The measured value (ca 97%) is in good agreement with theoretical predictions. Special attention was paid to the alignment procedures of all relevant optical components of the beamline.

Journal Article↗
PubMed1996

A randomized study of VAD therapy with either concurrent or maintenance interferon in patients with newly diagnosed multiple myeloma.

This randomized study was designed to determine whether response to VAD chemotherapy could be prolonged by using rh alpha-2b-interferon (IFN) at a dose of 3 mU three times per week, either concurrently with VAD (VIC) or as maintenance after completion of VAD (VIF). Maintenance IFN was given for 9 months in order for the duration of IFN therapy to be similar in both groups. 72 patients were randomized between December 1988 and August 1993. The majority of patients had poor prognostic features. The objective response rate was similar in each arm, 78% in VIF and 77% in VIC. Of the 56 responders, 33 have relapsed, three died in remission, and 18 proceeded to high-dose therapy, withdrew for other reasons or were lost to follow-up and were censored from analysis at the relevant time point. Only two patients remain in remission (both in partial remission). Median PFS was 15 months for both VIF and VIC, compared with 16.5 months for a historic control group treated with VAD alone (n.s.). The estimated median survival in VIF was 43 months and in VIC 22 months, compared with 45 months in the historic controls (n.s.). These findings indicate that neither maintenance nor concurrent IFN prolongs response to VAD.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1996

When to harvest peripheral-blood stem cells after mobilization therapy: prediction of CD34-positive cell yield by preceding day CD34-positive concentration in peripheral blood.

PURPOSE: To evaluate whether the CD34+ yield from a single peripheral-blood stem-cell (PBSC) harvest could be predicted by measurement of the patient's circulating WBC and CD34+ cell concentrations on the day before harvest. PATIENTS AND METHODS: Thirty-nine patients with hematologic or nonhematologic malignancy underwent 41 stem-cell mobilization episodes with cytotoxic chemotherapy and/or granulocyte colony-stimulating factor (G-CSF), and a total of 63 leukapheresis procedures were performed. Peripheral-blood samples were analyzed for WBC and CD34+ cell concentration both on the day before and the day of leukapheresis. RESULTS: The median WBC and CD34+ concentrations on the day preceding leukapheresis were 10.0 x 10(9)/L (range, 0.4 to 44.4) and 24.9 x 10(6)/L (range, 0.1 to 349.4), respectively. On the day of harvest, the corresponding figures were 15.1 x 10(9)/L (range, 1.5 to 52.6) and 29.3 x 10(6)/L (range, 0.1 to 543.1), respectively. The median CD34+ cell number collected in a single leukapheresis was 2.6 x 10(6)/kg body weight (range, 0.1 to 26.1). Both the preceding day (r = .84, P < .001) and harvest day (r = .95, P < .001) CD34+ circulating concentrations correlated significantly with the number of CD34+ cells per kilogram collected at leukapheresis. The correlation between CD34+ cells per kilogram collected and harvest day WBC count was also significant (r = .43, P <.001), but with the preceding day WBC count was nonsignificant. CONCLUSION: The number of CD34+ cells harvested in a single leukapheresis can be predicted by measurement of the preceding day peripheral-blood circulating CD34+ concentration, and on the basis of these data a table of probable CD34+ cell yield has been constructed. This correlation may facilitate the efficient organization of leukapheresis procedures.

Antigens, CD34↗
PubMed1990

Characterization of two hybrid C4 allotypes (C4A*12 and C4B*3) by electrophoretic, serological and restriction fragment length polymorphism analyses.

Informative pedigree analysis of two rare C4 allotypes is reported. One proband was C4A deficient as a consequence of having one haplotype with a deleted C4A gene, and the second haplotype with two C4B genes--one encoding the common C4B*1 and one encoding a unique hybrid gene product C4B*3. C4B*3 had approximately normal C4B hemolytic activity, a single alpha-chain of MR 94,000 by SDS-PAGE but was positive for Rg:1,2 by hemagglutination inhibition (HAI) and for Rg:1 by Western blotting. The hybrid nature was confirmed by RFLP analysis with a Rg:1-associated fragment by Eco0109 digestion but no C4A-associated fragments by N1aIV digestion were identified. A gene conversion at Locus I which included just the C4 isotype region could explain the structure of C4B*3. The second pedigree had a Rodgers negative C4A*12 allotype. This C4A gene, which segregated with a single 7.0 kb TaqI fragment, encoded a C4A alpha-chain, which was negative for Rg:1 epitope. The affected haplotype lacked the Rg:1-associated fragment by Eco0109 digestion yet had the C4A specific N1aIV digestion fragment. These studies successfully employed RFLP analyses to confirm serologic and electrophoretic observations.

Adolescent↗
PubMed1982

Intravascular coagulation in gestational hypertension and pre-eclampsia: the value of haematological screening tests.

Routine investigations designed to detect excessive intravascular coagulation in patients with gestational hypertension and pre-eclampsia have been analysed in 936 cases. Reticulocyte counts did not differ significantly from those in normal controls and abnormal red cell morphology was detected in only two patients. Fibrinogen degradation products and thrombocytopenia were found in about 10% of all hypertensive women and macrothrombocytosis in 32%. Neither reticulocyte counts nor the scanning of stained blood films for evidence of microangiopathic haemolysis have a place in the routine investigation of pre-eclampsia and it is doubtful whether any of the other screening tests can influence the management of patients with uncomplicated gestational hypertension. In fully developed pre-eclampsia, macrothrombocytosis is found in about 50% of patients, fibrinogen degradation products and thrombocytopenia in about 15%. All three parameters reflect the degree of clinical severity of the disease.

Blood Coagulation Tests↗
PubMed1981

The platelet count and mean platelet volume.

The Coulter Model S-Plus Counter provides a measure of the platelet count and the mean platelet volume (MPV). An analysis of 5000 unselected blood specimens showed an inverse relationship between the number of circulating platelets and their MPV. In nearly 95% of normal adults the platelet count varied from 150 to 450 X 10(9)/l and the MPV from 7.0 to 10.5 fl. Thrombocytosis was found in iron deficiency anaemia, after trauma and acute blood loss and in rhematoid arthritis. Although there is a normal platelet distribution in pregnancy, patients with pre-eclampsia and uncomplicated hypertension in late pregnancy tended to have lower platelet counts and larger platelets than controls. A variable platelet pattern was found in infection, renal failure and treated malignant disease.

Anemia↗
PubMed1981

Thrombocytopenia and macrothrombocytosis in gestational hypertension.

The platelet count in 550 patients with gestational hypertension was significantly lower and the mean platelet volume significantly higher than in normal pregnant women. Both the platelet count and volume became increasingly abnormal when hypertension was accompanied by oedema, proteinuria or both, and women with severe pre-eclampsia or eclampsia had the lowest platelet counts and the highest mean platelet volume. The proportion of patients with thrombocytopenia and/or macrothrombocytosis also varied with the severity of the clinical presentation. Fibrinogen degradation products were found mainly in fully developed pre-eclampsia. These findings confirm the concept of a rapid platelet turnover caused by low-grade disseminated intravascular coagulation in gestational hypertension. The platelet pattern in essential hypertension is similar to that seen in normal pregnancy.

Eclampsia↗
PubMed1974

The treatment of acute myeliod leukaemia.

The use of a combination of daunorubicin and cytosine arabinoside in the treatment of acute myeloid leukaemia in a district general hospital is described. The results in a series of 30 cases are considered.

Adolescent↗
PubMed1969

Outbreak of gastroenteritis due to Salmonella virchow in a maternity hospital.

An outbreak of gastroenteritis due to Salmonella virchow occurred in a maternity hospital in the Midlands in October-November 1968. Twenty-six babies and six mothers were infected. Fifteen of the babies had diarrhoea and 10 of these were in the special care baby unit The only fatal case was that of an infant with gross congenital malformations.The outbreak followed the admission of a patient to the delivery suite who was subsequently shown to be a symptomless excreter of S. virchow. A major factor in the spread of this organism is thought to have been heavy environmental contamination resulting from diarrhoea due to infection of her newborn baby.

Carrier State↗
PubMed1966

An account of 335 cases of megaloblastic anaemia of pregnancy and the puerperium.

The incidence of megaloblastic anaemia in pregnancy and the puerperium in north Staffordshire has steadily declined as a result of prophylaxis with folic acid. In the presence of advanced folic acid deficiency and with a florid megaloblastic marrow, the anaemia is usually severe, but in many patients the disease is relatively mild and the degree of anaemia is determined more by blood loss or associated iron deficiency than by the megaloblastosis. Microscopic examination of marrow films is still the most reliable method of diagnosis, although estimation of the labile serum folate has produced a 95% correlation with the marrow findings. There are three main factors which operate in the pathogenesis of megaloblastic anaemia in pregnancy and the puerperium. First, the maternal stores of folic acid are used up by the growing foetus, and this process is accelerated in multiple pregnancies, after haemorrhage, or in women with haemolytic anaemia. Secondly, an insufficient intake of folic acid, due to poor diet in pregnancy, plays a part in many cases. The third, and possibly the most important, factor is an absorption defect. Folic acid absorption is usually impaired in established cases, and this can still be demonstrated years later in a majority of patients, when they are neither pregnant nor anaemic. More than 20% of all cases also show abnormal fat absorption. An inherited defect in folic acid absorption may also explain why certain women appear to be constitutionally predisposed to megaloblastic anaemia of pregnancy and the puerperium, as shown by the abnormal blood group distribution in these patients and by the tendency of megaloblastic anaemia to recur not only in subsequent pregnancies, but, as in six of our cases, following other kinds of stress. The significance of commonly associated conditions like pre-eclampsia and infection is still incompletely understood. Although the treatment of megaloblastic anaemia is simple and effective, the main emphasis should be placed on prophylaxis by administering folic acid to all pregnant women.

Adult↗