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T Postma

Publications and source records attributed to T Postma.

12 recordsLinked to original sources
PubMed2000

Lamotrigine treatment during amygdala-kindled seizure development fails to inhibit seizures and diminishes subsequent anticonvulsant efficacy.

PURPOSE: Lamotrigine (LTG) is an anticonvulsant that is currently in use for the treatment of various seizure disorders and that shows promise in the treatment of affective illness. LTG is also effective in the suppression of amygdala-kindled seizures. Because many drugs show a differential efficacy profile as a function of the phase of kindling evolution, we evaluated LTG for its potential antiepileptogenic effects on the development of amygdala-kindled seizures. METHODS: In two separate studies, LTG (5 or 15 mg/kg versus vehicle) was administered before each daily amygdala stimulation (biphasic square wave pulses, 100 pulse pairs per second for a total of 0.5 second, 1-millisecond pulse width) at an intensity of 50 microA over the AD threshold. Seizure development was assessed, as well as the effect of this pretreatment on subsequent efficacy of LTG on completed kindled seizures. RESULTS: LTG at 5 mg/kg failed to block seizure development. At 15 mg/kg, LTG paradoxically enhanced seizure development and produced running fits in four of the nine animals tested. Animals previously treated with either dose of LTG during kindling development showed a diminished response to the anticonvulsant effects of LTG on fully kindled seizures compared with the vehicle-treated controls. CONCLUSIONS: Although LTG possesses potent anticonvulsant effects on completed amygdala-kindled seizures, it is either without effect (5 mg/kg) or facilitates (15 mg/kg) the initial phase of kindling development. In addition, exposure to LTG during kindled seizure development leads to a reduced subsequent response to the drug in fully kindled animals. These observations parallel those with carbamazepine and suggest that different stages of kindling (epileptogenesis versus fully manifest seizures) may have different underlying neural mechanisms that require distinct pharmacotherapies.

Amygdala↗
PubMed1997

Effect of intrathecal baclofen delivered by an implanted programmable pump on health related quality of life in patients with severe spasticity.

OBJECTIVES: To compare clinical effectiveness and health related quality of life in patients with severe spasticity who received intrathecal baclofen or a placebo. METHODS: In a double blind, randomised, multicentre trial 22 patients were followed up during 13 weeks and subsequently included in a 52 week observational longitudinal study. Patients were those with chronic, disabling spasticity who did not respond to maximum doses of oral baclofen, dantrolene, and tizanidine. After implantation of a programmable pump patients were randomly assigned to placebo or baclofen infusion for 13 weeks. After 13 weeks all patients received baclofen. Clinical efficacy was assessed by the Ashworth scale, spasm score, and self reported pain, and health related quality of life by the sickness impact profile (SIP) and the Hopkins symptom checklist (HSCL). RESULTS: At three months the scores of the placebo and baclofen group differed slightly for the spasm score (effect size=0.20) and substantially for the Ashworth scale (effect size=1.40) and pain score (effect size=0.94); health related quality of life showed no significant differences. Three months after implantation the baclofen group showed a significant, substantial improvement on the SIP "physical health", "mental health", "mobility", and "sleep and rest" subscales and on the HSCL mental health scale; patients receiving placebo showed no change. After one year of baclofen treatment significant (P<0.05) improvement was found on the SIP dimensions "mobility" and "body care and movement" with moderate effect sizes. Improvement on the SIP subscale "physical health" (P<0.05; effect size 0.86), the SIP overall score (without "ambulation"), and the "physical health" and overall scale of the HSCL was also significant, with effect sizes >0.80. Changes in health related behaviour were noted for "sleep and rest" and "recreation and pastimes" (P<0.01, P<0.05; effect size 0.95 and 0.63, respectively). Psychosocial behaviour showed no improvement. CONCLUSIONS: Intrathecal baclofen delivered by an implanted, programmable pump resulted in improved self reported quality of life as assessed by the SIP, and HSCL physical health dimensions also suggest improvement.

Adult↗
PubMed1992

MR imaging of skeletal metastases from medulloblastoma.

The findings of MR imaging in 3 patients with bone metastases from medulloblastoma are reported. The first patient showed focal lesions of low signal intensity on T1-weighted spin echo images at a time when bone scintigraphy was negative for metastases. This patient later developed extensive osteosclerotic lesions visible on plain films. The bone marrow of the second patient showed diffuse low signal intensity on T1-weighted images. After chemotherapy the signal intensity of the bone marrow increased which correlated with a return of normal hematopoietic tissue. A response to chemotherapy was also found on MR imaging and repeat bone marrow biopsies in a third patient. A consistent finding was a low signal intensity on pre-gadolinium images, but the pattern (focal or diffuse abnormal signal intensity) was different in each patient. To our knowledge, this is the first report on MR imaging findings in bone metastases from medulloblastoma.

Acetabulum↗
PubMed1987

Routine clinical determination of carotene, vitamin E, vitamin A, 25-hydroxy vitamin D3 and trans-vitamin K1 in human serum by straight phase HPLC.

A universal extraction procedure is described for fat-soluble vitamins in human serum. Methods are presented for routine quantitative analysis by isocratic straight phase HPLC with UV-detection of (alpha + beta)-carotene, vitamin E (alpha-tocopherol) and vitamin A (all-trans-retinol) in one single run, and of vitamin K1 (trans-phylloquinone) and 25-hydroxy vitamin D3 after sample clean-up using disposable reversed-phase cartridges. The limits of detection, precisions and selectivities of the developed assays are shown to be satisfactory after more than three years' experience. The routine clinical determination of fat-soluble vitamins can be performed in less than 5 mL of serum. Analyses of external quality control and randomly taken outpatient samples are shown to be of great value in assessing laboratory performance.

Calcifediol↗
PubMed1985

Monitoring serum CEA in women with primary breast tumours positive for oestrogen receptor and with spread to lymph nodes.

Serum carcinoembryonic antigen concentrations (serum CEA) in 80 patients with primary breast cancer were measured preoperatively, one month after operation, and thereafter serially every third month. These data were related to histological and morphometric features of the primary breast carcinoma and the lymph node metastases and to clinical follow up data. Analysis of the serum CEA values showed significant correlations with size of tumour, the presence of lymph node metastases, oestrogen receptor, and occurrence of distant metastases. Furthermore, the results indicated that serial determination of serum CEA in the first two years after operation may be useful in monitoring for the occurrence of distant metastases in patients with metastatic spread to lymph nodes and with large (greater than or equal to 2 cm) primary breast tumours positive for oestrogen receptor. In agreement with other studies, however, it was found that the predictive value of serum CEA concentrations in general is weak and costs may prohibit the implementation of the routine assessment of CEA concentrations.

Adult↗
PubMed1975

The diagnostic value of certain alkaline phosphatase isoenzyme patterns in human serum, fractions obtained by polyacrylamide disc electrophoresis.

Over 2500 pathological sera were analysed to determine alkaline phosphatase (EC 3.1.3.1) isoenzyme levels. 3% of these sera showed two or more narrow isoenzyme bands with a lower electrophoretic mobility on polyacrylamide than that of the intestine type of alkaline phosphatase and higher than that of the bile type of alkaline phosphatase (the extra-bands group). This latter group showed significantly more intestine-tupe alkaline phosphatase than a control group of 240 sera lacking extra serum bands. Significantly more of the individuals in the extra-bands group belonged to blood group O or B than did individuals of the control group. This relationship with blood groups suggests that the presence of the extra bands is genetically determined. It is concluded that the presence of these extra bands is not a specific indication for a particular disease or malignant process. The serum of seven patients showed an unusually strong alkaline phosphatase band with a relative mobility amounting to about one-third of that of the liver-type band (2nd fraction group). Specificity for a particular disease could not be established in this group either. In four patients the serum showed an alkaline phosphatase band with an electrophoretic mobility greater than that of the liver-tupe band (6th fraction group). All of these patients had liver metastases of a primary adenocarcinoma localized in the pancreas or stomach. After the demonstration of this fraction in ther serum, the course became progessively worse.

ABO Blood-Group System↗