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W Waters

Publications and source records attributed to W Waters.

At least 19 recordsLinked to original sources
PubMed2005

Frequency of truly cryptic subtelomere abnormalities--a study of 534 patients and literature review.

Frequency of truly cryptic subtelomere abnormalities - a study of 534 patients and literature review. Unbalanced subtelomere chromosome rearrangements are a significant cause of mental retardation with approximately 5% of over 3000 affected individuals tested worldwide having a chromosome rearrangement of this type. Many of these abnormalities are detectable using routine karyotyping at the 550 band level and therefore are not considered to be cryptic. The frequency of truly cryptic subtelomere abnormality should be less than 5% but has not been established. In this study, we defined 'cryptic abnormality' as one not detectable at the 550 band level on routine karyotyping. Using this as one of the selection criteria, we have studied 534 individuals with mental retardation/ developmental delay (MR/DD) and referred for subtelomere study by clinical geneticists. We have identified seven cases with cryptic subtelomere abnormalities. The clinical features of the seven abnormal cases are summarized. Literature review identified five publications on the identification of subtelomere abnormalities which used similar recruitment criteria: (a) normal karyotype at the 550 band level and (b) subjects were selected for subtelomere studies. Combining the data from these studies with those of the current study, 1154 patients were tested and 30 subtelomere abnormalities were identified. We estimate the frequency of truly cryptic subtelomere abnormality to be approximately 2.6% (30/1154) in children with MR/DD who are referred for subtelomere study.

Abnormalities, Multiple↗
PubMed1991

Metaiodobenzylguanidine (mIBG) in treatment of 47 patients with neuroblastoma: results of the German Neuroblastoma Trial.

From 1984 to 1989, 47 children with relapsed, refractory, and/or metastasized neuroblastoma were treated with 131I-metaiodobenzylguanidine (mIBG) in several different treatment combinations. At initial diagnosis, 36 children had Evans stage IV and 11 stage III disease. In 16 of the 47 children, tumor recurred after complete remission prior to mIBG treatment, 26 of 47 progressed from residual or nonresponding tumor, and in 5 of 47 tumor progression during chemotherapy was observed. Altogether the children were treated with a total of 112 courses (range 1-6) with a mean dosage of 8.9 +/- 6.7 mCi/kg body weight/treatment course. Total dose was 283.2 +/- 203.7 mCi for stage III and 388.9 +/- 218.6 mCi for stage IV. Nine of 47 children reached a complete or a very good partial remission (CR and VGPR) from mIBG treatment alone, 13 of 47 achieved partial remission (PR). In an early analysis, 10 patients treated with mIBG in the neuroblastoma trial NB 85 of the German Society of Pediatric Oncology showed no significant difference in survival time compared with 30 conventionally treated children. However, the recent therapy series has been done with higher doses of mIBG, and during improved therapeutic scanning many more bone lesions could be detected than during earlier diagnostic scanning. We conclude that mIBG treatment has not yet fulfilled the expectations for it but still seems for certain indications to be a promising tool to treat neuroblastoma in the future. Moreover, the frontier of neuroblastoma detection is still advancing.

3-Iodobenzylguanidine↗
PubMed1991

[The effect of hyper- and hypothyroidism on the energy metabolism of skeletal muscles--a study using 31P-magnetic resonance spectroscopy].

31P magnetic resonance spectroscopy allows non-invasive evaluation of phosphorus metabolism in man. The purpose of the present study was to assess the influence of hyper- and hypothyroidism on the metabolism of resting human skeletal muscle. The present data show that quantitative measurement of phosphate metabolism by NMR is possible as also demonstrated by other studies. Using a quantitative evaluation method with an external standard, significant differences in the levels of phosphocreatine, adenosine triphosphate, and phosphodiesters were found. In hypothyroid patients a TSH-dependent increase in phosphodiesters and a decrease in adenosine triphosphate and phosphocreatine was observed. In hyperthyroidism a similar decrease in adenosine triphosphate but a considerably higher decrease in phosphocreatine occurred. In the light of the results of other studies of muscle metabolism, these changes appear to be non-specific so that further studies are required to assess the clinical value of such measurements.

Adenosine Triphosphate↗
PubMed1990

[Neopterin as a marker of aspecific immunostimulation with Propionibacterium avidum KP-40 in patients with gastrointestinal tumors. A prospective randomized study].

This prospective randomized study demonstrated that a preoperative intravenous infusion of 10 mg of the bacterial preparation Propionibacterium avidum KP-40 to patients with gastrointestinal tumors significantly (P less than 0.001) enhanced the secretion of neopterin, measurable as long-lasting (greater than 16 days) elevated urine excretion. Postoperative re-infusion of P. avidum KP-40 caused (statistically significant (p less than 0.001] re-enhancement of neopterin urine levels.

Adult↗
PubMed1990

Immunoscintigraphic imaging of mIBG-negative metastases in neuroblastoma.

We report a study of seven children with recurrent stage IV neuroblastoma comparing the uptake pattern of 123I-metaiodobenzylguanidine (mIBG) with 99mTc-labeled monoclonal antibody (MAb) BW 575 by the tumor lesions. Immunofluorescence studies of bone marrow had verified specific binding of the antibody to the tumor cells. The majority of tumor sites was detected both by mIBG and MAb scans. However, five of 26 lesions were not detected by mIBG and eight of 26 were false negative by immunoscintigraphy. The false negative lesions by mIBG belonged to five different patients (one of five primary, four of five bone marrow). In conclusion, MAb BW 575 may detect mIBG-negative neuroblastoma sites. The presence of antibody-negative sites suggests the utilization of both scintigraphy methods together.

3-Iodobenzylguanidine↗
PubMed1986

Transplantation of cryopreserved hepatocytes or liver cytosol injection in the treatment of acute liver failure in rats.

Intraperitoneally injected cryopreserved hepatocytes or liver cytosol were used for the treatment of acute galactosamine-induced liver failure in rats. Both methods were similarly capable to improve the survival rates as compared to control groups. Furthermore, a new viability test for transplanted hepatocytes, using a nuclearmedical tracer technique, was evaluated in this study. This test demonstrated viability of intraperitoneally transplanted hepatocytes for at least 6 days after operation. Cytosol injection should be preferred to hepatocyte transplantation in the treatment of acute liver failure, avoiding the problems of cell storage and post-transplant immunosuppression.

Acute Disease↗
PubMed1986

Three-dimensional imaging in medicine: holography.

Two holographic methods for three-dimensional imaging in medicine are presented. The methods can be applied on the base of various primary projection methods, especially those of nuclear medicine and roentgenology. This three-dimensional display, which is not bound to complicated technical equipments such as computers and graphic displays, can be performed easily at any place: in conference rooms, in surgical units etc. It may be of particular importance for the surgeon in order to visualize the site directly and in its real space dimensions.

Holography↗
PubMed1984

[Localization of cerebrospinal fluid fistulas with CT cisternography].

Positive CT cisternography has proved a useful method for the accurate pre-operative localisation of liquor fistulae from the skull base. In this way, planning of surgery can be improved with respect to the operative approach and the area to be covered. The risk of a recurrence is also reduced. It is necessary, however, to have a clinically recognisable leak at the time of the examination, since it is otherwise difficult to indicate the flow during the examination. We regard persistent or recurrent liquorrhoea as an indication for this examination, irrespective of its cause, provided it is intended to proceed to surgery after a positive finding. The method has few complications, is easy to perform and, in case of recurrence, can be repeated.

Adult↗
PubMed1984

The influence of elevated iodide supply on the autonomously functioning thyroid gland.

A pharmacokinetic two-compartment model of iodine metabolism has been established on the basis of data from the literature and our own experimental investigations. By this model it is possible to estimate the effects either of prolonged elevation of iodide supply or of a single administration of a high dose of inorganic iodide in the presence of autonomously functioning thyroid tissue. Prolonged elevation of iodide supply in regions of iodine deficiency will cause manifest hyperthyroidism in many cases of thyroidal autonomy (cases with facultative hyperthyroidism). The administration of a single high dose of iodide, as it is proposed for the situation of an accident in a nuclear power station (100 mg NaI) in order to reduce the radiation burden to the surrounding population, carries almost no risk in cases of thyroid autonomy.

Disaster Planning↗
PubMed1983

Clinical significance of endogenously labelled thyroid hormones in the diagnosis of thyroidal autonomy.

The clinical value of the determination of 123I concentration in serum 48 hrs after tracer administration (123I)48 is investigated with special regard to thyroidal autonomy. Serum radioiodine concentration, thyroid radioiodide uptake at 4 and at 48 hrs were measured in 74 healthy subjects and patients with simple goiter, in 36 patients with thyroidal autonomy (diagnosis by thyroid suppression test), and in 20 hyperthyroid patients. 83% of the patients with elevated radioiodine concentration belonged to the group of thyroidal autonomy. The product of radioiodine concentration and thyroid radioiodide uptake is a much better parameter. 95% of the patients in which this product was elevated, belonged to the autonomy group (5% diagnostic error). Also in the control group the diagnostic error was 5%. The combination of (123I)48 with the result of the TRH-test is very useful in excluding thyroidal autonomy, if (123I)48 is normal and the TRH-test is positive (100% of the patients have regulated thyroid glands). 94% of the patients having elevated (123I)48 and a negative TRH-test belonged to the group of thyroidal autonomy. A very useful combination for the diagnosis of borderline hyperthyroidism is the determination of the product of (123I)48 and the uptake48 together with the pulse rate or fine tremor of the fingers (or TRH-test). The results suggest that the determination of (123I)48 is a very good parameter of thyroidal autonomy beside the thyroid suppression test. It may be used alone for the diagnosis of thyroidal autonomy if the suppression test is contraindicated. In the diagnosis of borderline hyperthyroidism its determination makes the suppression test unnecessary in many instances.

Humans↗
PubMed1982

[Determination of the serum concentration of radioiodine with 123I].

Though the half-life of 123I is much shorter than that of 131I, the determination of the radioiodine concentration 48 hrs after tracer administration (123I)48h can be done with the same precision. This precision is achieved by the fivefold dose given to the patient and the fourfold specific count rate. In 36 euthyroid patients with thyroidal autonomy the 123I concentration in serum was determined 48 hrs after tracer administration and was compared with the values obtained in a control group (n = 74). The diagnosis of thyroidal autonomy can be supported by the measurement of (123I)48h. The combination of (123I)48h and thyroidal radioiodine uptake seems to make the diagnostic decision more precise.

Humans↗