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Biomedical subjects

N Jackson

Publications and source records attributed to N Jackson.

At least 55 records · Page 3Linked to original sources
PubMed1997

Macular haemorrhage in adult acute leukaemia patients at presentation and the risk of subsequent intracranial haemorrhage.

Retinal changes are common in adult acute leukaemia patients at presentation, but whether they correlate with the risk of subsequent intracranial haemorrhage is unknown. A 4-year study has been carried out in 82 newly-diagnosed acute leukaemia patients, aged 12-77 years, who were studied prospectively for the presence of intra-retinal haemorrhages (IRH), white-centred haemorrhages (WCH), cotton-wool spots (CWS) and macular haemorrhages (MH). Groups with and without these features were compared for their risk of intra-cranial haemorrhage (ICH) within the first 30 d following diagnosis. There was no association between the incidence of ICH and the presence of IRH, WCH or CWS. However, 6/13 of those with MH developed ICH, compared to 6/69 of those without MH (relative risk 5.0, CI 95% [2.03-12.33], P=0.003). The only other identifiable risk factor for ICH was the M3 subtype of AML, but if the four cases of M3-AML were discounted from analysis, MH remained a highly significant risk factor for ICH. Patients with MH should be monitored intensively for the development of ICH, and receive priority in the allocation of platelets where these are in short supply.

Adolescent↗
PubMed1997

Fatal Campylobacter jejuni infection in a patient splenectomised for thalassaemia.

A 35 year old man with a fatal Campylobacter jejuni infection is described. He had HbE/beta zero thalassaemia and had undergone splenectomy nine months previously for hypersplenism; he also had chronic hepatitis C infection. He presented with high grade fever but no gastrointestinal symptoms and rapidly progressed to septicaemic shock and hepatic encephalopathy despite treatment with penicillin, gentamicin, and, later, chloramphenicol and ceftazidime. Only one case of Campylobacter jejuni septicaemia occurring post-splenectomy has been reported previously, also in an iron overloaded thalassaemia patient. Unusual Gram negative bacilli must be covered by the chosen antibiotic regimen when splenectomised thalassaemic patients present with high grade fever.

Adult↗
PubMed1997

Correlation between simple clinical parameters and the in vitro humidification characteristics of filter heat and moisture exchangers. Groupe de Travail sur les Respirateurs.

STUDY OBJECTIVE: This study on ventilated patients in ICUs examined a large sample of heat and moisture exchanger filters (HMEFs) to determine whether simple clinical parameters are correlated with exchanger humidity output. DESIGN: A total of 594 HMEFs (18 types of HMEF) were tested in nine university hospital ICUs. PATIENTS: Each HMEF was tested on one different unselected and consecutive patient for 24 h. INTERVENTIONS: The following parameters were rated at each tracheal aspiration on a scale of 0 to 3: secretion abundance, viscosity (Visc), suction catheter adherence (Adh) to the endotracheal tube, and the amount of water condensed in the flex tube (Cond). Individual values for each type of HMEF and each variable were averaged and correlated with the humidity output (HO) of the HMEFs, values which were supplied by the manufacturers. RESULTS: There were significant correlations between HO and Cond (r=0.82, p<10(-3)), Visc (r=-0.67, p=0.002), and Adh (r=-0.56, p=0.01). A second study recorded the same variables, for three consecutive 24-h periods, using first a high-humidifying HMEF (DAR Hygrobac), followed by a low-humidifying one (Pall BB22-15), and again DAR Hygrobac. Visc and Adh were higher (p<0.05) and Cond was lower (p<0.05) with the Pall than with the DAR. CONCLUSIONS: Simple clinical parameters correlate well with the efficiency of HMEFs. The apparent water condensed in the flex tubing seems to be the best indicator of the humidifying efficiency of HMEFs.

Adhesiveness↗
PubMed1996

Sideroblastic anemia recurring during two pregnancies.

A 25-year-old lady presented with a severe normocytic anemia (Hb 5.3 g/dl) and a sideroblastic marrow at the end of her first pregnancy. Six months into the puerperium, after the transfusion of a total of 8 units of red cells, there was apparent spontaneous improvement and then she was lost to follow-up. After a second pregnancy without clinical problems, she presented during a third pregnancy, at the age of 30 years, with similar hematological findings. Twenty-two months later she was well with a normal blood count. One possible reason for relapse in pregnancy is the increased demand for pyridoxine that occurs, but only one other case of sideroblastic anemia relapsing during pregnancies has been reported.

Adult↗
PubMed1996

Retinal findings in adult leukaemia: correlation with leukocytosis.

The associations between retinal findings and haematological parameters in acute leukaemia are controversial. Sixty-three newly-diagnosed acute leukaemia patients, aged 12-77 years, were studied prospectively for the presence of intra-retinal haemorrhages (IRH), white-centred haemorrhages (WCH), cotton wool spots (CWS) and macular haemorrhages (MH), Thirty-three patients (52.4%) showed at least one retinal abnormality. The prevalence of individual findings was: IRH (30 cases), WCH (20 cases), CWS (5 cases), MH (11 cases). In contrast to previous studies, there was no association between any of these retinal findings and the haemoglobin level or the platelet count. There was a higher median WBC in patients with IRH (68 x 10(9)/l) than in those without IRH (15.4 x 10(9)/l), P = 0.037. When the acute myeloblastic leukaemia cases were considered separately, an association was also found between higher WBC and the presence of WCH and CWS. There was no association between retinal findings and FAB type in the AML cases. We conclude that a high WBC may be at least as important as anaemia and thrombocytopenia in the pathogenesis of the retinopathy of acute leukaemia.

Acute Disease↗
PubMed1995

Renal response to candoxatrilat in patients with heart failure.

OBJECTIVES: Our primary objective was to compare the effects of three different doses of candoxatrilat with the effects of placebo on urinary volume in patients with moderately severe heart failure. The effects of candoxatrilat on urinary composition, neuroendocrine indexes and renal hemodynamic function were also studied. BACKGROUND: Candoxatrilat, a neutral endopeptidase inhibitor, reduces degradation of atrial natriuretic peptide and provokes diuresis in patients with mild heart failure, but the renal effects have not been studied in patients with moderately severe heart failure in a placebo-controlled study. METHODS: In a double-blind crossover trial, the effects of intravenous boluses of saline vehicle (placebo) and 50, 100 and 200 mg of candoxatrilat were compared on separate days in 12 patients with heart failure. Urinary output and composition were measured for 8 h. Renal blood flow and glomerular filtration rate were determined by radionuclide techniques. Blood was withdrawn for the measurement of hormones before and 3 h after dosing. RESULTS: All doses of candoxatrilat increased urinary volume (e.g., [mean +/- SEM] 263 +/- 53 to 490 +/- 82 ml for saline solution and the 200-mg dose, respectively, p < 0.01) and sodium content (14 +/- 4 to 37 +/- 11 mmol, p < 0.001) in the 1st 4 h after dosing. Plasma atrial natriuretic peptide increased (140 +/- 26 to 279 +/- 37 pg/ml, p < 0.01), whereas aldosterone decreased (178 +/- 41 to 125 +/- 35 pg/ml, p < 0.01), and renin activity was unchanged (10 +/- 2 to 12 +/- 3 ng/ml per h). CONCLUSIONS: Candoxatrilat given acutely causes diuresis, even in patients with moderately severe heart failure.

Aged↗
PubMed1995

Randomized trial of intravenous immunoglobulin prophylaxis for patients with chronic lymphocytic leukaemia and secondary hypogammaglobulinaemia.

Forty-two patients with chronic lymphocytic leukaemia (CLL), serum IgG levels < 5.5 milligrams and a history of two or more recent infections, were randomized to receive infusions of 18 g human intravenous immunoglobulin (IVIg) or human albumin placebo every three weeks. During the 12 month study 122 infections were documented but only four were associated with neutropenia. Ten patients (24%) with IgG levels < 3.0 milligrams experienced 65% of the infections. In response to IVIg there were immediate and accumulative increases in serum IgG levels and an associated decrease in total and serious infections. If three further infections occurred, placebo patients were commenced on 18 g IVIg, and IVIg patients were increased to 24 g IVIg. Approximately 50% of these cases subsequently remained infection free. The study shows the usefulness of prophylactic Sandoglobulin in CLL patients with hypogammaglobulinaemia, and suggests that this may be justified in those with recurrent infections and serum IgG levels < 3 milligrams.

Agammaglobulinemia↗
PubMed1995

A comparison of the effects of IGF-I and insulin on glucose metabolism, fat metabolism and the cardiovascular system in normal human volunteers.

The metabolic and cardiovascular effects of recombinant human IGF-I were compared to insulin in six normal subjects. Subjects were studied twice and intravenously received an infusion of [6,6-2H2]glucose (0-480 min) and in random order either IGF-I 20 micrograms kg-1 h-1 (43.7 pmol kg-1 min-1 or insulin 0.5 mU kg-1 min-1 (3.4 pmol kg-1 min-1) with an euglycaemic clamp. One subject was withdrawn following a serious adverse event. During the IGF-I infusion glucose appearance rate (Ra) decreased from 1.79 +/- 0.13 at baseline (150-180 min) to 0.35 +/- 0.26 mg kg-1 min-1 (P < 0.01) at 360 min, and glucose utilization rate (Rd) increased from 1.79 +/- 0.28 to 4.17 +/- 0.84 mg kg-1 min-1 (P < 0.01). There was no change in free fatty acids (FFA) and an increase (percentage change from pre-infusion mean) in cardiac output +l37.3% +/- 9% (P < 0.01), heart rate +13% +/- 2% (P < 0.01) and stroke volume +21% +/- 7% (P < 0.05). During the insulin infusion glucose Ra decreased from 1.89 +/- 0.13 to 0.34 +/- 0.33 mg kg-1 min-1 (P < 0.01) and FFA from 0.546 mmol l-1 to 0.198 mmol l-1 (P < 0.01), glucose Rd increased from 1.89 +/- 0.18 to 5.41 +/- 1.47 mg kg-1 min-1 (P < 0.01) and there were no significant changes in the cardiovascular variables.

Adult↗
PubMed1995

Puerperal acquired factor VIII inhibitor causing a von Willebrand-like syndrome in a patient with anti-DNA antibodies.

A 30-year-old Malay lady, with no previous or family history of bleeding, presented with severe gum bleeding 25 days post-partum. The factor VIII:c was 0.03 iu/ml with evidence of a slow-acting factor VIII inhibitor. Von Willebrand factor antigen (VWF:age) varied from less that 0.05 to 0.17 iu/ml, and there was absent ristocetin-induced platelet aggregation. Anti-nuclear and anti-DNA antibodies were present, but there were no other features of systemic lupus erythematosus. There was some clinical response to cryoprecipitate and tranexamic acid, and slight improvement with corticosteroid. Fifteen months later, the patient has no active bleeding problem, and her VWF-ag is increasing spontaneously. However, factor VIII:c is less than 0.01 iu/ml and her factor VIII inhibitor titre is still > 20 Bethesda units/ml.

Adult↗
PubMed1995

M3-variant of acute promyelocytic leukaemia. A case report in a Malay boy.

The variant form of acute promyelocytic leukaemia (AML-M3) possesses its own characteristic morphology, although usually a few of the cells may have cytoplasmic features of typical AML-M3. In contrast to typical AML-M3, this M3-variant form commonly presents with hyperleucocytosis. As in typical AML-M3, disseminated intravascular coagulopathy (DIVC) occurs in the M3-variant. A boy with this morphological variant of AML-M3 is described. Uncharacteristically, his presenting white blood count was low, and DIVC was present before treatment was started. Six days into intensive chemotherapy his coagulopathy worsened and he subsequently died of intracranial haemorrhage. An alternative approach to the treatment of AML-M3, with the use of retinoids, is discussed.

Child, Preschool↗
PubMed1995

Autosomal dominant thrombocytopenia with microthrombocytes: a family study.

A family demonstrating autosomal dominant thrombocytopenia is described. A 28-year-old Malay housewife was found to have a platelet count of 40 x 10(9)/l with a low mean platelet volume (6.8 fl) while being investigated prior to ovarian cystectomy. The bone marrow was consistent with immune thrombocytopenia but she failed to respond to appropriate therapy. Five siblings, one parent and one nephew have easy bruising and platelet counts of 39-82 x 10(9)/l. Platelet aggregation studies excluded a major functional defect. Survival of homologous platelets in the circulation was normal. Familial thrombocytopenias are rare but important to differentiate from the common acquired thrombocytopenias in order to spare the patient unnecessary treatments.

Adult↗
PubMed1995

Adult idiopathic thrombocytopenic purpura without the option of splenectomy.

In this part of Malaysia, consent of splenectomy is virtually unobtainable, so we studied the outcome of ITP without this treatment option. Thirty-two adult patients were seen, but 7 defaulted before therapy evaluation. Of the remaining 25, 17 achieved a complete remission with prednisolone, but in only 8 was this prolonged. Twelve patients, who failed to respond to prednisolone or who required > 15 mg/day as maintenance, were offered splenectomy, but all fused. Of these 12: one has died from an intracranial haemorrhage; three others have defaulted while on no treatment with platelet counts of < 16 x 10(9)/1; one has had a baby who died from intracranial bleeding. The other seven patients have platelet counts ranging from 4 - 202 x 10(9)/1 with moderate bleeding on doses of prednisolone of 0-60 mg/day: long-term corticosteroid side-effect are evident in all but one of them. This study demonstrates that ITP patients who refuse splenectomy have a high morbidity.

Adolescent↗
PubMed1993

Reduction of plasma prolactin by acute administration of CB-154 in ovariectomized F344 and Holtzman rats treated with diethylstilbestrol: a comparison of RIA and Nb2 lymphoma bioassay.

Fischer 344 (F344) and Holtzman Sprague-Dawley female rats were ovariectomized and implanted with a s.c. Silastic capsule of diethylstilbestrol (DES). At 1, 4 and 8 weeks of DES exposure, blood samples were obtained by infraorbital sinus puncture under light ether anesthesia before and 2 hours after s.c. administration of CB-154 (2.5 mg/rat). The plasma obtained was assayed for prolactin by radioimmunoassay (RIA) and Nb2 lymphoma cell bioassay (BA). At 1 week of DES treatment plasma prolactin in F344 rats measured by RIA was decreased by CB-154 (approximately 60%) whereas the level measured by BA was not changed and the BA:RIA ratio was increased from 2.4 +/- 0.2 to 4.8 +/- 0.9. CB-154 decreased plasma prolactin levels at 4 weeks but the effect seen by RIA (approximately 80%) was greater than that seen by BA (approximately 60%) and the BA:RIA ratio was increased (2.2 +/- 0.2 vs 3.4 +/- 0.5). By 8 weeks of DES exposure, CB-154 was as effective in reducing the levels measured by BA (approximately 89%) as those measured by RIA (approximately 85%) and the BA: RIA was not affected by the dopamine agonist. In Holtzman rats CB-154 decreased prolactin levels measured by RIA and BA to the same extent at both 1 and 4 weeks resulting in no change in the BA:RIA ratio, but at 8 weeks the BA:RIA was decreased by CB-154 (2.1 +/- 0.1 to 1.7 +/- 0.1). As was observed in F344 rats, the reduction in plasma prolactin induced by CB-154 increased as the duration of DES treatment increased (1 week approximately 45%; 4 weeks approximately 55-60%; 8 weeks approximately 80-85% inhibition) regardless of assay method. It is concluded that DES increases the BA:RIA ratio of plasma prolactin and that acute CB-154 treatment increases, decreases or does not change the BA:RIA ratio depending on the strain of rat used and the duration of DES treatment.

Animals↗
PubMed1993

Hydroxyurea treatment for chronic myeloid leukaemia during pregnancy.

A patient being treated for chronic myeloid leukaemia with hydroxyurea became pregnant. Despite an increase in the dose of hydroxyurea (to 3 g per day) during the pregnancy, her white blood cell count could only be controlled at about 150 x 10(9)/l. A healthy baby girl was born at 37 weeks with normal blood counts and no evidence of congenital abnormality. There are now five reports of the use of hydroxyurea in pregnancy, and where leukapheresis is not available it may be the treatment of choice.

Adult↗
PubMed1993

Acute myocardial infarction survival rate and complications after streptokinase therapy in Hospital Universiti Sains Malaysia, Kelantan--a comparative study.

Thrombolytic therapy is a well-established therapy in acute myocardial infarction (AMI), reducing mortality and infarct size. This study is a retrospective analysis of survival and complications after the use of streptokinase at Hospital Universiti Sains Malaysia. Streptokinase was first used here in March 1990. Between then and February 1992, 126 patients were admitted to the Coronary Care Unit. Thirty-two patients who fulfilled our criteria for thrombolytic treatment were given an hour intravenous infusion of 1.5 MU streptokinase, and started on aspirin. A control group of 64 patients selected from before March 1990, and matched for age, sex and site of infarct, was given standard therapy. The survival at 4 weeks post-AMI was 91% in the streptokinase therapy group and 91% in both groups (p > 0.05). The complications encountered were reperfusion arrhythmias (2 patients), hypotension(1), maculopapular rash(1) and gum bleeding(1). None of these complications were statistically increased when compared to the control group and none resulted in the death of a patient. We conclude that streptokinase therapy can be given safely in a rural Malaysian setting. Our survival and complication rates are comparable with other published series.

Adult↗
PubMed1991

A double-blind, placebo-controlled, parallel dose-response study of amlodipine in stable exertional angina pectoris.

A placebo-controlled, double-blind, dose-response study of amlodipine (1.25, 2.5, 5, and 10 mg once daily) was carried out in 136 patients with stable exertional angina pectoris. Improvements in total exercise tolerance, time to onset of angina during exercise, ST-segment deviation at maximum common load, frequency of angina attacks, and nitroglycerin consumption were greater following amlodipine than placebo. The maximum improvement in exercise parameters occurred with the highest dose of amlodipine. All doses produced significant reductions in angina attack frequency and the rate of nitroglycerin consumption. Amlodipine was well tolerated and no patients were withdrawn due to adverse events or laboratory abnormalities.

Adult↗