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T Martin

Publications and source records attributed to T Martin.

At least 37 records · Page 2Linked to original sources
PubMed2001

Long-term effects on the intelligence of children treated for acute lymphoblastic leukemia.

The purpose of this study was to investigate whether the intelligence quotient (IQ) in children treated for leukemia decreases in the years following whole brain irradiation. Twenty-seven leukemic children were assessed following a mean time lapse between radiotherapy and IQ measurement of 9 years. The IQ test used was the Hamburg Weschsler Intelligence Test for Adults. The IQ results did not differ significantly, p > 0.05, from the IQs of the general population. It was found that age and dose were not predictors of a decrease in IQ. The only predictor was time lapse between irradiation and IQ measurement, which we found to be indicative of an IQ decrease even after 9 years. Time lapse between irradiation is a useful predictor of IQ.

Adult↗
PubMed2001

Effect of NASA light-emitting diode irradiation on wound healing.

OBJECTIVE: The purpose of this study was to assess the effects of hyperbaric oxygen (HBO) and near-infrared light therapy on wound healing. BACKGROUND DATA: Light-emitting diodes (LED), originally developed for NASA plant growth experiments in space show promise for delivering light deep into tissues of the body to promote wound healing and human tissue growth. In this paper, we review and present our new data of LED treatment on cells grown in culture, on ischemic and diabetic wounds in rat models, and on acute and chronic wounds in humans. MATERIALS AND METHODS: In vitro and in vivo (animal and human) studies utilized a variety of LED wavelength, power intensity, and energy density parameters to begin to identify conditions for each biological tissue that are optimal for biostimulation. RESULTS: LED produced in vitro increases of cell growth of 140-200% in mouse-derived fibroblasts, rat-derived osteoblasts, and rat-derived skeletal muscle cells, and increases in growth of 155-171% of normal human epithelial cells. Wound size decreased up to 36% in conjunction with HBO in ischemic rat models. LED produced improvement of greater than 40% in musculoskeletal training injuries in Navy SEAL team members, and decreased wound healing time in crew members aboard a U.S. Naval submarine. LED produced a 47% reduction in pain of children suffering from oral mucositis. CONCLUSION: We believe that the use of NASA LED for light therapy alone, and in conjunction with hyperbaric oxygen, will greatly enhance the natural wound healing process, and more quickly return the patient to a preinjury/illness level of activity. This work is supported and managed through the NASA Marshall Space Flight Center-SBIR Program.

Animals↗
PubMed2001

Sinorhizobium meliloti cells require biotin and either cobalt or methionine for growth.

Sinorhizobium meliloti is usually cultured in rich media containing yeast extract. It has been suggested that some components of yeast extract are also required for growth in minimal medium. We tested 27 strains of this bacterium and found that none were able to grow in minimal medium when methods to limit carryover of yeast extract were used during inoculation. By fractionation of yeast extract, two required growth factors were identified. Biotin was found to be absolutely required for growth, whereas previously the need for this vitamin was considered to be strain specific. All strains also required supplementation with cobalt or methionine, consistent with the requirement for a vitamin B(12)-dependent homocysteine methyltransferase for methionine biosynthesis.

Biotin↗
PubMed2001

[Radiotherapy in vertebral hemangioma].

Vertebral hemangiomas are the most common benign spinal tumors with an incidence range of 10-12%. Approximately 1-2% of the cases develop clinically significant symptoms causing the necessity for treatment. Based on our own results and a review of the literature we discuss the role of radiotherapy in the management of symptomatic vertebral hemangiomas. A total dose of 30.0 Gy given in five weekly fractions of 2.0 Gy has been proven as effective for the primary treatment and postsurgical irradiation for the prevention of a recurrence. In the literature review the results are summarized of 59 reports in the period of 1929-2000 for a total of 327 cases. The analysis of 55 studies reporting results in 210 cases which underwent primary radiotherapy or combinations with other methods of treatment demonstrated that in 54% occurred a complete relief of symptoms (CR), in 32% a partial relief (PR), and 11% were non-responders (NR). The analysis of 21 reports of 63 cases which were treated with radiotherapy as the sole measure of treatment demonstrated that 57% had a complete remission of symptoms (CR), 32% a partial remission (PR), and 11% did not respond to radiotherapy (NR). We conclude that radiation therapy is very effective in the management of symptomatic vertebral hemangiomas. With regard on the delayed effects of the irradiation, cases with an acute compression of the spinal cord should be treated primarily with a surgical procedure and a postsurgical irradiation is recommended to prevent a relapse of symptoms. In order to minimise acute or late toxicity and the risk of radiation-induced neoplasms the total dose should not exceed 30 Gy.

Adult↗
PubMed2001

Hypofractionated radiotherapy for Graves' orbitopathy.

BACKGROUND: Radiotherapy (RT) has been proven effective in the management of Graves' orbitopathy in numerous studies. Most commonly is the use of conventional fractionated RT and the value of hypofractionated irradiation has not been investigated. MATERIALS AND METHODS: The results in 33 euthyroid cases who underwent RT with a total dose of 21.0 Gy given in three weekly fractions of 3.0 Gy are retrospectively analyzed. The duration of symptoms ranged from 1-84 months and all of the cases had treatment failure after previous administration of corticosteroids. After a mean follow-up period of 33.6 months the overall results were assessed according to the criteria by Donaldson et al. and for evaluation of the clinical outcome a classification with the main criteria being eye-lid changes, exophthalmos, myopathy and eye nerve involvement was used. RESULTS: At follow-up, the overall response to RT was 84.8% (28/33 cases). The analysis with the clinical classification demonstrated that in 19/33 (57.6%) cases occurred a decrease of eye lid changes and exophthalmos and 12/33 (36.4%) had a relief of myopathy. 2/33 cases (6.0%) developed an eye nerve compression causing the necessity of surgical decompression. 3/33 cases (9.0%) had a progression of at least of one of the single criteria of the score and therefore they were classified as non-responders. CONCLUSIONS: Hypofractionated RT has been proven effective for treatment of severe cases of Graves' orbitopathy in cases with a prolongated duration of symptoms. The comparison with literature data demonstrate that the results after hypofractionated RT are comparable to those obtained after conventional fractionated RT.

Adult↗
PubMed2001

Analgesic efficacy of orally administered buprenorphine in rats.

The analgesic effect of orally administered buprenorphine was compared with that induced by a standard therapeutic injected dose (0.05 mg/kg of body weight, s.c.) in male Long-Evans rats. Analgesia was assessed by measuring pain threshold, using the hot-water tail-flick assay before and after administration of buprenorphine. The results suggest that a commonly used formula for oral buprenorphine in flavored gelatin, at a dose of 0.5 mg/kg, does not increase pain threshold in rats. Instead, oral buprenorphine doses of 5 and 10 mg/kg were necessary to induce significant increases in pain threshold. However, these doses had to be administered by orogastric infusion because the rats would not voluntarily eat flavored gelatin containing this much buprenorphine. The depth of analgesia induced by these infused doses was comparable to that induced by the clinically effective s.c. treatment (0.05 mg/kg).

Administration, Oral↗
PubMed2000

Lung hypoplasia in a patient with del(2)(q33-q35) demonstrated by chromosome microdissection.

We report on a 17-month-old girl with multiple malformations, including lung hypoplasia, multiple ventricular septal defects, craniofacial anomalies, and malrotation of the intestine. Moreover, the patient showed Robin sequence, developmental delay, as well as pre- and postnatal growth retardation. Postnatal cytogenetic analysis revealed an interstitial deletion on the long arm of chromosome 2. Microdissection and reverse chromosome painting of the aberrant chromosome 2 as well as FISH with a panel of chromosome 2q band-specific YACs mapped the deletion to 2q33-q35. Lung hypoplasia has not been described so far in patients with del(2)(q33-q35). A review of previously reported patients showed variable phenotypes apparently due to different deleted chromosomal segments.

Abnormalities, Multiple↗
PubMed2000

Investigation of the prevalence of Legionella species in domestic hot water systems.

AIMS: To investigate the prevalence of Legionella spp. in the hot water systems of a representative sample of Wellington domestic residences with electrically heated hot water systems, and to investigate risk factors (eg water temperature, plumbing materials) for such contamination. METHOD: 100 households with electrically heated hot water systems in the Wellington area were investigated. Samples of hot water from several hot water outlets were collected, and characteristics of the plumbing system were recorded. Water samples and swabs were cultured and further examined by polymerase chain reaction (PCR) and direct fluorescence antibody (DFA) testing to identify Legionella spp. and serogroups. RESULTS: No Legionella spp. were isolated by culture. PCR tested positive for Legionella in specimens from twelve residences. Six of these were also positive by DFA testing. The only environmental factor found to be associated with the presence of Legionella was recent plumbing work on the hot water system. Five of the twelve PCR-positive residences, and four of the six DFA-confirmed residences had hot water delivery temperatures in excess of 60 degrees C. CONCLUSIONS: The results suggest that either Legionellae colonise domestic hot water reticulation systems and/or that the organisms are killed during passage through the hot water tank. Both possibilities may be correct. Further work to characterise the microbial ecology of Legionella-positive hot water distribution systems would be useful, as would the development of improved methods for culturing the organisms from potable water.

Humans↗
PubMed2000

Salivary gland lymphomas in patients with Sjögren's syndrome may frequently develop from rheumatoid factor B cells.

OBJECTIVE: Patients with Sjögren's syndrome (SS) have an increased risk of developing monoclonal B cell non-Hodgkin's lymphomas (MNHL), which frequently occur in the salivary glands (SG). The transition from the benign lymphocyte infiltrate of the gland that characterizes SS to MNHL is not well understood. Previous sequence analyses of the expressed variable (V) region genes have supported the theory that the surface Ig (sIg) plays an important role in the initial expansion of nonmalignant B cell clones and in lymphomagenesis. However, the antigenic specificities of these B cells were unknown. We describe the specificities of the Ig expressed by 2 cases of MNHL that developed in the SG of 2 patients with SS. METHODS: The expressed V genes were amplified by polymerase chain reaction from biopsy specimens, sequenced, and subcloned into eukaryotic expression vectors. The constructs were transfected into P3X63-Ag8.653 cells to obtain 2 monoclonal cell lines, each secreting 1 of the sIg expressed by the MNHL. These IgM were tested by enzyme-linked immunosorbent assay and immunofluorescence against a panel of antigens potentially implicated in SS. RESULTS: Our main finding was that the Ig products of the neoplastic B cells were rheumatoid factors (RF). Contrary to expectations, they did not react with nuclear or cytoplasmic antigens, double-stranded DNA, self antigens commonly bound by natural autoantibodies, or SG tissue. CONCLUSION: Previous analyses of V gene use have provided indirect evidence that SG MNHL may frequently express RF. We demonstrate that this hypothesis is true in the 2 patients we studied. Large-scale studies will be needed to establish the exact frequency of RF specificity among SS-associated MNHL.

Aged↗
PubMed2000

Cytotoxic T lymphocyte antigen 4 (CD152) regulates self-reactive T cells in BALB/c but not in the autoimmune NOD mouse.

Recent studies demonstrated that engagement of cytotoxic T lymphocyte antigen 4 (CTLA-4)/(CD152) generates an inhibitory signal to T cells which arrests an on-going immune response. Since aberrant CD152 activity is thought to contribute to autoimmunity, we examined the effect of CD152-mediated inhibitory signals on the response to self and foreign antigens in autoimmune, diabetes-prone NOD and non-autoimmune BALB/c mice. The interaction of CD152 with its ligand B7 was prevented by treating the mice with anti-CD152 blocking antibody, before and following immunization of the mice with the self-antigen, syngeneic islet cells, or the foreign antigen, key-hole limpet hemocyanin (KLH). CD152 blockade in BALB/c mice stimulated a robust islet-specific T cell-mediated immune response compared to control antibody-treated mice. The augmentation of T cell responses in BALB/c mice was consistent with the role proposed for CD152 as a down-regulator of T cell activation responses. Furthermore, CD152 blockade unmasked islet cell specific autoreactive T cells in the non-autoimmune BALB/c mouse. Conversely, CD152 blockade in NOD mice failed to regulate islet-specific auto-reactive T cell responses. However, CD152 blockade enhanced the T cell response to the exogenous, foreign antigen KLH in both non-autoimmune BALB/c and autoimmune NOD mice. Collectively, these results suggest that there is not a global defect in CD152-mediated regulation of peripheral T cell immune responses in NOD autoimmune mice but rather, a defect specific to T cells recognizing self antigen.

Abatacept↗
PubMed2000

3D interstitial HDR brachytherapy combined with 3D external beam radiotherapy and androgen deprivation for prostate cancer. Preliminary results.

BACKGROUND: Evaluation of feasibility, tolerance and efficiency for a new 3D interstitial HDR brachytherapy technique combined with 3D external beam radiotherapy and androgen deprivation for prostate cancer. PATIENTS AND METHODS: Between January 1997 and August 1998 we treated 35 patients with stage cT1-3 N0 M0 prostate cancer. Thirty-two patients with a follow-up of 12 to 28 months (median: 18 months) were evaluated. After ultrasound-guided transrectal implantation of 4 non-parallel needles, CT based 3D brachytherapy treatment planning ("Offenbach system") was performed. All patients received 4 fractions brachytherapy using a fractional dose of 5 or 7 Gy. Time between each fraction was 14 days. After brachytherapy 3D external irradiation followed up to 39.6 or 45.0 Gy. All patients received androgen deprivation, starting 2 to 19 months before brachytherapy, ending 3 months after 3D external radiotherapy. RESULTS: Posttreatment PSA levels dropped to < 1.5 ng/ml in 29/32 patients (91%). In 25 patients PSA levels were < 0.5 ng/ml, in 4 patients 0.5 to 1.5 ng/ml. In 2 patients we noted biochemical relapse. Transrectal implantation was very well tolerated. Grade 3 acute urinary toxicity occurred in 1 patient. We noted no Grade 2 or higher acute gastrointestinal toxicity. One patient developed a Grade 3 late urinary toxicity. No patient showed late gastrointestinal side effects. All 140 dose-volume histograms for 3D HDR brachytherapy were analyzed. CONCLUSIONS: The new 3D HDR brachytherapy technique, combined with 3D external irradiation and androgen deprivation, is a feasible, so far well-tolerated and effective treatment in the short-time follow-up of median 18 months.

Adenocarcinoma↗
PubMed2000

Randomized multicenter trial documenting the efficacy and safety of a lactose-free and a lactose-containing formula for term infants.

OBJECTIVE: To evaluate the efficacy and safety of a new lactose-free infant formula. DESIGN: Randomized, prospective, double-blind, controlled, outpatient, multicenter, parallel 12-week trial. SETTING: Ambulatory-care facilities of the participating centers. SUBJECTS: 137 healthy term infants (approximately 7 days old at the time of study enrollment). INTERVENTION: Healthy term infants, whose mothers had decided not to breast-feed, were randomly assigned 1 of the 2 study formulas. MAIN OUTCOME MEASURES: Weight, length, and occipitofrontal circumference measurements were obtained at baseline and when the infant was 2, 4, 8, and 12 weeks old. Formula acceptance and tolerance were also assessed at weeks 2, 4, 8, and 12. Serum albumin concentration, creatirune level, and blood urea nitrogen were determined at baseline and week 12. Adverse events were assessed throughout the study. STATISTICAL ANALYSES PERFORMED: Each baseline anthropometric and laboratory variable was analyzed for comparability between groups using the Student t test and was also analyzed using a repeated-measures analysis of variance method. Covariance analysis was applied to the final laboratory data using the respective baseline data as covariates. Decisions about equality of mean responses to formula effects were based on the .05 level of significance in all cases. RESULTS: One hundred four infants completed the study. No significant differences between the 2 formula groups were noted for any of the growth and blood parameters. APPLICATIONS: This new formula is an effective and safe lactose-free nutrition alternative for infants who require such a diet.

Anthropometry↗
PubMed2000

Navigation system for interstitial brachytherapy.

PURPOSE: To develop a computed tomography (CT) based electromagnetic navigation system for interstitial brachytherapy. This is especially designed for situations when needles have to be positioned adjacent to or within critical anatomical structures. In such instances interactive 3D visualisation of the needle positions is essential. METHODS AND MATERIALS: The material consisted of a Polhemus electromagnetic 3D digitizer, a Pentium 200 MHz laptop and a voice recognition for continuous speech. In addition, we developed an external reference system constructed of Perspex which could be positioned above the tumour region and attached to the patient using a non-invasive fixation method. A specially designed needle holder and patient bed were also developed. Measurements were made on a series of phantoms in order to study the efficacy and accuracy of the navigation system. RESULTS: The mean navigation accuracy of positioning the 20.0 cm length metallic needles within the phantoms was in the range 2.0-4.1 mm with a maximum of 5.4 mm. This is an improvement on the accuracy of a CT-guided technique which was in the range 6.1-11.3 mm with a maximum of 19.4 mm. The mean reconstruction accuracy of the implant geometry was 3.2 mm within a non-ferromagnetic environment. We found that although the needles were metallic this did not have a significant influence. We also found for our experimental setups that the CT table and operation table non-ferromagnetic parts had no significant influence on the navigation accuracy. CONCLUSIONS: This navigation system will be a very useful clinical tool for interstitial brachytherapy applications, particularly when critical structures have to be avoided. It also should provide a significant improvement on our existing technique.

Brachytherapy↗
PubMed2000

Evaluation of the BACTEC MGIT 960 system for the recovery of mycobacteria.

We evaluated the BACTEC MGIT 960 system, which is a fully automated, non-invasive, continuous monitoring system for the growth and detection of mycobacteria. Including respiratory and other specimens, 1,742 specimens were processed and inoculated into the BACTEC MGIT 960 and the BACTEC 460 TB Systems, as well as onto Lowenstein-Jensen (L-J) media. A total of 104 isolates of mycobacteria were recovered from all culture systems. This included Mycobacterium tuberculosis complex, Mycobacterium avium-intracellulare (MAI) complex and other mycobacteria (MOTT). The isolation rates for M. tuberculosis complex and MAI complex were comparable for the BACTEC 460 (54.8% and 13.5%) and the BACTEC MGIT 960 (51.9% and 13.5%). The overall isolation rate was less for BACTEC MGIT 960 (76.9%) which was due to lesser number of MOTT isolates recovered from this system. The mean times to detection (TTD) for all mycobacteria were 9.3 days for the BACTEC MGIT, 14.6 days for the BACTEC 460 and 21.6 days for L-J. A significant difference was observed when TTD was tested in relation to degree of positivity in smears, with the BACTEC MGIT maintaining the short TTD even with less number of bacilli in the smear. The contamination rates were, 6.4% for BACTEC MGIT, 2.9% for BACTEC 460 and 12.1% for L-J medium. The BACTEC MGIT 960 system shows performances comparable to the BACTEC 460 and seems to be a dependable, user friendly system.

Culture Media↗
PubMed2000

Subsets of macrophages and dendritic cells in nonobese diabetic mouse pancreatic inflammatory infiltrates: correlation with the development of diabetes.

Islet-specific T cells are essential in the development of type I diabetes. The role of non-lymphoid cells is relatively unclear, although infiltration of dendritic cells and macrophages is the first sign of islet autoimmunity in diabetes-prone nonobese diabetic (NOD) mice. BDC2.5 is one of the autoreactive T cell clones isolated from NOD mice. Transfer of BDC2.5 T cells into young NOD mice accelerates diabetes development, whereas transgenic expression of the BDC2.5 T cell receptor on NOD T cells (BDC2.5 TCR-Tg NOD) markedly reduces diabetes development. We show that, although the same antigen-specificity is involved, both models differ significantly in insulitis. BDC2.5 TCR-Tg NOD mice develop an extensive, but non-aggressive, peri-insulitis by 3 weeks of age. In these large peri-islet infiltrates, resembling secondary lymphoid tissue, BM8+ macrophages (Mphi) are virtually absent. In contrast, BDC2.5 T cell clone transfer results in an aggressive insulitis with small infiltrates, but relatively large numbers of BM8 Mphi. Infiltration of BM8+ Mphi therefore correlates with islet destruction. This is, however, not observed for all Mphi; Monts-4+ Mphi follow a reverse pattern and are present in higher numbers in BDC2.5 TCR-Tg than in transferred mice. ER-MP23+ Mphi are reduced in both transferred and transgenic mice compared with wild-type NOD. Thus, this study underlines and extends previous data suggesting that Mphi are implicated in both early and late phases in diabetes development. Furthermore, our data imply that subsets of non-lymphoid cells have different roles in diabetes development. It is, therefore, important to recognize this heterogeneity when interpreting both in vivo and in vitro studies concerning non-lymphoid cells in diabetes.

Animals↗
PubMed2000

Isosorbide mononitrate and propranolol compared with propranolol alone for the prevention of variceal rebleeding.

The aim of this study was to test the effectiveness of isosorbide-5-mononitrate (IM) as an adjunct to propranolol (PR) in the prevention of variceal rebleeding. Ninety-five cirrhotic patients with variceal bleeding were randomly assigned to treatment with PR + IM (46 patients) or PR alone (49 patients). Eighteen patients in the PR + IM group and 28 in the PR group had rebleeding during the 2 years after randomization. The actuarial probability of rebleeding 2 years after randomization was lower in the PR + IM group (40.4% vs. 57.4%) but the difference was not significant (P =. 09). However, the decrease in the risk of rebleeding reached statistical significance after stratification according to age, i.e. less than 50 versus >/=50 years old, (P =.03) or by adding an additional year of follow-up (P =.05). No significant difference was found in rebleeding index and survival. The multivariate Cox analysis indicated first, that both treatment (P =.03) and age (P =. 001) were factors predictive of rebleeding and second, that PR + MI reduced the risk of rebleeding by half (relative risk: 0.51, 95% confidence interval: 0.28-0.95). Seven patients in the PR + MI group and 1 patient in the PR group had to discontinue one of the drugs because of adverse events (P =.03). These results suggest that the addition of IM improves the efficacy of PR alone in the prevention of variceal rebleeding in cirrhotic patients. However no beneficial effects were observed on other parameters reflecting the efficacy of treatment.

Adrenergic beta-Antagonists↗