Alanine-ESR dosimetry for radiotherapy. IAEA experience

At present, the most commonly used transfer dosimeters for radiotherapy applications are TL dosimeters. They are being used for intercomparison between SSDLs (about 70) and the IAEA dosimetry laboratory. However, there are some undesirable characteristics of this dosimetry system. We have a study in progress at the IAEA to evaluate the alanine-ESR system as an alternative to TLDs. There are several desirable qualities which make alanine an attractive dosimeter. Preliminary data suggest that the alanine-ESR dosimetry system has the potential to replace TLDs for intercomparison amongst SSDLs in the therapy-level dose region.     

Late effects of intraoperative radiotherapy]

One group (145 isolates) of Neisseria gonorrhoeae was collected from municipal clinics in Bloemfontein in 1994 and a second group (65 isolates) in 1995. Penicillin and tetracycline MICs were determined and plasmid analysis performed to monitor antimicrobial susceptibilities in conjunction with the occurrence of plasmids in these isolates. The prevalence of penicillin resistance caused by beta-lactamase plasmids remained constant at 9% during the study period. Three high-level tetracycline-resistant strains (MICs 16 mg/L), the first to be detected in South Africa, were isolated in 1994. Although there was a reduction in the percentage of isolates harbouring 24.5 MDa conjugative plasmids (from 79% in 1994 to 46% in 1995), this was partially counteracted by an increase in TetM-encoding conjugative plasmids (25.2 MDa) from 2% to 18.5%. The tetM genes of 13 isolates shown to exhibit high-level tetracycline resistance were characterized as the American type. The American-type tetracycline resistance plasmid was demonstrated in 11 isolates. Digestion with Bg/l showed that two isolates harboured tetM-encoding plasmids that differed from the American- and Dutch-type plasmids described previously: one isolate contained a plasmid that produced two fragments of different sizes from those of the American-type plasmid and the second isolate possessed an American/Dutch hybrid plasmid. Auxotyping/serotyping and random amplified polymorphic DNA analysis revealed a predominant tetracycline-resistant family (NR/IA-6, genomic group I) in Bloemfontein. As there is a high incidence of chlamydial infections in southern Africa requiring tetracycline therapy, selective pressures exist in the environment for the maintenance and rapid spread of high-level tetracycline-resistant N. gonorrhoeae. It is possible that tetM genes may have emanated from Botswana and/or Namibia to Bloemfontein. The establishment of high-level tetracycline-resistant N. gonorrhoeae in Bloemfontein was seen to be complex as a related group of strains was identified, plasmid dissemination was evident and two new TetM-encoding plasmids were demonstrated. The appearance of these TetM-encoding plasmids indicates either that the American- and Dutch-type plasmids are continuing to evolve or that tetM genes are being introduced into different families of 24.5 MDa conjugative plasmids.     

Video laparoscopic adrenalectomy. The authors'' personal experience]

A prospective, randomized, open-label, single-dose study was conducted in an emergency department (ED) of a tertiary care teaching hospital to evaluate the efficacy of hyoscyamine sulfate as compared to ketorolac tromethamine for the reduction of pain from ureteral colic in the ED. Patients were included if they were at least 18 years of age and presented to the ED with an initial history and physical examination consistent with ureteral colic. Ureteral calculi were confirmed by ultrasound or intravenous urogram. Consecutive patients were randomized to either a single sublingual dose of 0.125 mg of hyoscyamine sulfate or a single intravenous dose of 30 mg of ketorolac tromethamine given over 1 minute. After 30 minutes, if analgesia was inadequate, patients were given rescue medication. Baseline pain scores were obtained using a horizontal, 100-mm visual analog scale. Additional pain scores were obtained at 10-minute intervals for 30 minutes. Upon completion of the study, both patients and physicians completed a global assessment score questionnaire. Fifty-four evaluable patients were randomized. Demographics and baseline pain scores were similar for each group. Decreasing trends in pain over time were observed for both treatment groups, with significantly greater pain reduction observed with ketorolac tromethamine as compared to hyoscyamine sulfate. Global evaluations of pain relief revealed better results in the ketorolac tromethamine group than in the hyoscyamine sulfate group, although this result was not statistically significant.     

The results of radiotherapy for ependymomas: the Mayo Clinic experience

It is known that exogenous 11-cis-retinol inhibits the recovery of photosensitivity of bleached rod outer segments (ROS) and 11-cis-retinol exists in the interphotorecepter matrix. We examined the conversion of 11-cis-retinol with bovine ROS. ROS was incubated with 11-cis-retinol under dim red light. Retinoids were extracted from the reaction mixture with hexane and analyzed by HPLC coupled with a fluorescence spectrophotometer. Isomerization of 11-cis-retinol to all-trans-retinol was observed in the presence of ROS. This isomerization was not suppressed by heat treatment and did not have stereospecificity. In addition, we incubated purified rhodopsin and phospholipids extracted from ROS with 11-cis-retinol. Rhodopsin was found to isomerize 11-cis-retinol to all-trans-retinol as well as ROS, but phospholipids did not. In contrast, the phospholipids inhibited the isomerization of 11-cis-retinol to all-trans-retinol by the purified rhodopsin. Commercially available phospholipids, especially phosphatidylserine, also inhibited the isomerization. Our results suggest that rhodopsin has activity for the isomerization of 11-cis-retinol to all-trans-retinol and may play an important role in the detoxification of 11-cis-retinol in the ROS.     

Occlusion of patent ductus using the Rashkind system. Initial experience]

Three patients were submitted to the Rashkind device technique for closure of a patent ductus arteriosus. The percutaneous transvenous technique was employed in every cases. A 12 mm prosthesis was utilized in one case and 17 mm prostheses in the other two cases. In the first case, after temporary occlusion of the ductus arteriosus, the prostheses was removed due to the technical impossibility of evaluation of the proximal umbrella position. In the second and third cases, the prostheses were duly liberated in the proper position, thus occluding the defects. This technique does not require general anesthesia, is indicated in patients over 6 kgs of body weight, and is a therapeutic alternative to the habitual surgical procedure.     

Value of radiotherapy in disseminated high-grade non-Hodgkin''s lymphoma]

The usefulness of immunohistochemical demonstration with anti-bromodeoxyuridine (BrdU) monoclonal antibody for estimating proliferative activity was evaluated in experimental meningeal carcinomatosis model. The experimental model was developed by inoculation of 1 x 10(4) Walker 256 carcinosarcoma cells into the cisterna magna of female Wistar rats. Every consecutive day after tumor inoculation, the rat was perfused by saline and then sacrificed 30 min after intravenous BrdU (200 mg/Kg) injection. The brain was removed, fixed in 80% ethanol and embedded in paraffin. Coronal sections of the brain 6 mu in thickness were obtained and stained immunohistochemically using the indirect immunoperoxidase (ABC) method with anti-BrdU monoclonal antibody (Becton-Dickinson). The sections were counterstained by hematoxylin. Labeling index (LI) which represented the percentage of tumor cells in synthetic phase was obtained by counting immunoreactive cells under the microscope. LI was as low as 10.8% to 16.9% in the first 3 days after tumor inoculation. Four to 6 days after tumor inoculation when tumor cells grew several layers in the subarachnoid space, LI was 24.0% to 40.1%. LI increased to reach a plateau around 40.7% to 48.2%, 7 to 9 days after tumor inoculation. Ten days after inoculation when necrosis appeared in the tumor, BrdU-positive cells declinded and LI was between 29.1% to 35.0%. It is a useful method to estimate the proliferative activity of the experimental brain tumors, design treatment modalities and evaluate the effect of chemotherapeutic agents by using immunohistochemical demonstration with anti-BrdU monoclonal antibody. Therefore, we suggest that chemotherapy against malignant leptomeningeal tumors shall be carried out in early or intermediate stage before the proliferative activity reaches its plateau stage.     

Salvage surgery after unsuccessful radiotherapy of laryngeal cancer]

The methods usually employed for reconstruction of total lower eyelid loss include (1) tarsoconjunctival flaps from the upper eyelid and skin-graft cover and (2) chondromucosal grafts and local skin-flap cover. We report a technique for coverage of these defects with an island flap involving the full thickness of the ipsilateral nasal wall based on the dorsal (external) nasal vessels, terminal branches of the ophthalmic vessels. The advantages of this method are (1) the main components of the eyelid (skin, tarsus, conjunctiva) are reconstructed in a single short operation, even under local anesthesia, (2) there is one donor area that can be closed primarily without significant deformity, (3) the upper lid remains intact, and ectropion is improbable, and (4) the procedure involves a short hospitalization. As disadvantages we might mention bulkiness of the new eyelid and difficult dissection of the (subcutaneous) pedicle.     

Oncologic surgery of the larynx after failure of radiotherapy]

An association between complete congenital heart block (CCHB) and anti-Ro/SSA antibody is well recognized but has never been reported in Thailand. We report here a 37-year-old female who was admitted because of massive epistaxis secondary to immune thrombocytopenia. She had given birth to a child with CCHB 2 years previously, when she was healthy. Antinuclear antibody and anti-Ro/SSA were positive in her sera, but were negative in her son. The relationship between anti-Ro/SSA antibody and outcome of mothers with infants with CCHB is reviewed.     

On the cost and benefit of cost and benefit.

Cost–benefit analysis of RTs has become a popular chronometric tool in the study of cognitive processes. The present authors review the technique, assumptions underlying its application, and pitfalls that are encountered in actually implementing it in various experimental contexts. It is suggested that the unthoughtful application of the technique may cause one to draw improper conclusions about the underlying mechanisms that produce costs and benefits. (56 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The cost of psychotherapy.

Examines the relationship between psychotherapy funding policies and concepts of mental health. Three levels of mental health (necessity, improvement, and potentiality) are proposed. Necessity represents basic adaptation, the current dominant level illustrated by brief psychotherapy funded through managed mental health care. Improvement is the phase beyond necessity aimed at prevention and heightened quality of life, and potentiality is the ideal. The latter 2 now receive limited funding and emphasis. At question are both economic and social policies that endorse a narrow rather than a broad conception of mental health. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Authors'' experience with transvaginal administration of progestagens]

Prognostic value of some clinical factors on the course of subsequent pregnancy in 117 women with unexplained recurrent spontaneous abortion undergoing immunization with paternal lymphocytes were evaluated in the study. The results allow to conclude that high efficiency of alloimmunization in preventing consecutive abortions (87.2% in our own study) does not seem to depend significantly on: the woman's and her partner's age, number, type (primary vs. secondary), and time of previous miscarriages, coexistence of subfertility, time from immunization to the fertilization and the number of lymphocytes used for the procedure (as far as it concerns the number of lymphocytes isolated from 100 ml of blood). In our results, alloimmunization is most effective in preventing a missed abortion (in comparison with "live" spontaneous abortion).     

The role of radiotherapy in the palliative treatment of cancer]

Radiotherapy has a well-established role in palliative care of patients with cancer. It is a local treatment of short duration, the number of fractions should be kept to a minimum without loss of efficacy. Radiotherapy can control superior vena caval obstruction, spinal cord compression, brain metastases, painful bone metastases, and tumor-related bleeding.