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Radio Frequency Signals in Jupiter's Atmosphere

During the Galileo probe's descent through Jupiter's atmosphere, under the ionosphere, the lightning and radio emission detector measured radio frequency signals at levels significantly above the probe's electromagnetic noise. The signal strengths at 3 and 15 kilohertz were relatively large at the beginning of the descent, decreased with depth to a pressure level of about 5 bars, and then increased slowly until the end of the mission. The 15-kilohertz signals show arrival direction anisotropies. Measurements of radio frequency wave forms show that the probe passed through an atmospheric region that did not support lightning within at least 100 kilometers and more likely a few thousand kilometers of the descent trajectory. The apparent opacity of the jovian atmosphere increases sharply at pressures greater than about 4 bars.

Journal Article↗

Minimal requirements in defined media for improved growth of some radio-resistant pink tetracocci.

Defined media permitting extensive growth of representative pink radio-resistant tetracocci (Micrococcus radiodurans, Micrococcus roseus, and Micrococcus radiophilus) and two controls (an ultraviolet-sensitive mutant of M. radiodurans and Micrococcus luteus) are described. Availability of Fe (especially Fe3+) proved essential for good growth, as evidenced by (i) favorable effects of hydroxamic acids, e.g., salicylhydroxamic acid, and (ii) the growth promotion by hemin when joined with elevated concentrations of Fe. Cobalamin (B12) and methionine were interchangeable as an absolute requirement for methionine not affected by B12. M. luteus required neither. Pink radio-resistant micrococci may form a coherent group. Some divergences among them might be attributable to the method for isolating them, which for ordinary bacteria would be mutagenic to the point of total lethality. The ecology of these tetracocci vis-à-vis other pink-red radio-resistant organisms is discussed in relation to a question: can these bacteria be isolated without dependence on radiation as the cardinal selective factor?

Culture Media↗

Osteoid osteoma: percutaneous radio-frequency ablation.

PURPOSE: To evaluate a percutaneous technique for in situ destruction of osteoid osteoma. MATERIALS AND METHODS: Radio-frequency ablation was performed in 18 patients with osteoid osteoma (17 male, one female; age range, 8-42 years). Diagnosis was established by means of clinical and radiographic features and confirmed by means of needle biopsy findings. No attempt was made to remove the lesion. A small radio-frequency electrode introduced into the lesion through the biopsy track was used to produce thermal necrosis of a 1-cm sphere of tissue. RESULTS: Symptoms were completely relieved in 16 (89%) of 18 patients. In one patient, a second procedure was required for pain relief. All but two patients underwent treatment as outpatients: These two were hospitalized for 1 night only. All patients resumed normal daily activities immediately. No casts or external supports were required; there were no complications. Twelve patients were followed up for more than 1 year. There were no recurrences CONCLUSION: Radio-frequency ablation of osteoid osteoma is a promising alternative to surgery in selected patients.

Activities of Daily Living↗

Neoadjuvant radio-chemotherapy of adenocarcinoma of the oesophagogastric junction.

BACKGROUND: Recently, neoadjuvant radio-chemotherapy has been demonstrated to induce tumour remission and to prolong survival of patients with locally advanced adenocarcinoma of the oesophagogastric junction.The present study was performed to re-evaluate these data. PATIENTS AND METHOD: A non-randomised trial of multimodal treatment was conducted in order to investigate histopathologic response and survival of patients with adenocarcinoma of the oesophagogastric junction. Treatment consisted of 2 courses of combined chemotherapy with 15 mg/kg 5-fluorouracil on days 1-5 and 75 mg/m(2) cisplatin on day 8 and simultaneous radiation (40 Gy), and a second course starting on day 36, followed by surgery. Abdomino-thoracic oesophagectomy and systematic 2-field lymphadenectomy were performed in patients with Barrett's carcinoma. D2-gastrectomy was performed in patients with type 2 or 3 cancer of the oesophagogastric junction according to the Siewert classification. Probability of survival was estimated using the Kaplan-Meier method. RESULTS: 16 patients with a mean age of 57 years were enrolled in this study. Surgery was performed in 14 of these patients. Response to treatment was evident in 10 patients, but none of these patients had complete histopathologic response. Toxicity related to radiochemotherapy was mild to moderate (37.5%). Perioperative complications, both medical and surgical, occurred in 71.4% of patients. 2 patients had fatal complications. 30-day mortality was 25.4%. The probability of survival at 2 years after surgery was 61.2%. CONCLUSION: Neoadjuvant radio-chemotherapy followed by surgery for cancer of the oesophagogastric junction is associated with a considerable rate of complications. Histopathologic response to radio-chemotherapy is poor. In consequence of these preliminary results, the present study was terminated and the protocol of a future study was modified.

Adenocarcinoma↗

Radio-immunolocalization in nude mice using anticytokeratin monoclonal antibodies.

Four monoclonal antibodies reactive with the rod portion of human cytokeratin No. 8 were evaluated using experimental tumour radio-immunolocalization. Nude mice carrying human HeLa cell tumours were injected with 125I-labelled F(ab')2 fragments or intact IgG antibodies. Positive immunolocalization was observed with all the specific antibodies, the intact antibodies being superior to their analogous F(ab')2 fragments. High localization efficiency was observed despite the fact that the targets are intracellular filaments. The presence of necrotic areas in the tumours may favour the high uptake in the tumours. By computerized gamma-scintigraphic evaluation of the antibody distribution in the animals, several kinetic parameters of the antibody behaviour in vivo could be determined. The biological half-lives in the tumours were determined to be greater than 600 h for some of the antibodies compared to a half-life of 40-80 h in non-tumour tissues. Optimal imaging was obtained as late as 10-14 days after administration of the antibody. Up to 10% of the injected antibody could be identified in the tumours, indicating a potential value in radio-immunolocalization and radio-immunotherapy using anticytokeratin antibodies.

Adenocarcinoma↗

Palmar dislocation of the radio-carpal joint: a case report.

Radio-carpal joint dislocation, with or without fracture of the radius, is an uncommon injury; only 21 cases have previously been reported. Successful treatments of closed reduction and surgery have also been reported. A 35-year-old right-handed man was injured in a traffic accident and taken to an emergency room of a hospital, where radiographic examination showed a right palmar radio-carpal joint dislocation. Three days after injury, the patient was transferred to our department at Tokyo Medical University, Tokyo. We performed percutaneous pin fixation to maintain the position of his reduced radio-carpal joint. Two years postoperatively, radiographic examination showed a complete union of the avulsion fracture of the radius and a reduction of the joint. He had no marked disturbance in his daily activities apart from a slight pain while working. He had no limitation on the range of motion of the wrist joint and his grip strength was 41.6 kg. He returned to work 3 months after injury.

Accidents, Traffic↗

A simple, artificial-membrane feeding method for the radio-isotope labelling of Aedes aegypti polypeptides in vivo.

An artificial feeding unit has been designed and constructed to feed laboratory-bred Aedes aegypti with a radio-isotope (35S), so that the mosquitoes' polypeptides can be labelled in vivo. In the unit, a piece of Parafilm M barrier film is stretched over the bottom, outer surface of a polystyrene Petri dish, to create a small gap in which the mixture of blood and radio-isotope is placed. Warm water is placed in the dish, to keep the blood at about 37 degrees C. When such units were placed on net-covered rearing cages, almost all (80%-90%) of the female mosquitoes in the cages took bloodmeals from them. When checked by polyacrylamide-gel electrophoresis and autoradiography 1 h after feeding had begun, the blood-fed mosquitoes were found to have radio-labelled polypeptides. The unit is simple, easy to handle, disposable and can be used to offer small blood samples (>or=50 microl) to Ae. aegypti and, presumably, other mosquito species.

Aedes↗

Monitoring radio programs and time of day affect simulated car-driving performance.

Whether radio monitoring, task difficulty, and time of day affect driving performance was examined in a computer-controlled, simulated driving task. Driving performance was defined as the absolute deviation of the car position from road midline as displayed on the computer monitor. We found for 12 men and 8 women (i) an expected, marked deterioration of performance with increasing task difficulty, (ii) a deterioration of performance in the morning, and (iii) a deterioration of performance when subjects concurrently listened to radio programs except for the easy task conducted in the morning. The latter is supposed to be caused by a reactive increase of effort, which is induced by the concurrent radio monitoring and stimulated through a perceived impairment of attention.

Adult↗

Solid-phase double-antibody radio-immunoassay for atrial natriuretic factor.

A solid-phase radio-immunoassay for the determination of atrial natriuretic factor (ANF) in human plasma is described. Iodination of alpha hANF was carried out with the iodogen method. Purification of radio-iodinated alpha hANF was performed by chromatography on disposable columns of DEAE-Sephadex A-25. Studies of immunoreactivity and the elution pattern on HPLC showed perfect stability of the labelled compounds. The tracer was usable for 28 weeks after preparation, and the batch-to-batch variation in the quality of the tracer was satisfactory. Immunoreactive ANF was extracted from human plasma with Sep-Pak C18 cartridges. Recovery of alpha hANF added to whole blood was 85 +/- 12% (mean +/- SD, n = 12). The sensitivity of the radio-immunoassay was 1.6 pg/tube, equivalent to 1 pg/ml plasma when assaying the extract from 4 ml plasma. Mean plasma ANF values in normal subjects in the supine position was 23 +/- 12 pg/ml (mean +/- SD, n = 21).

Atrial Natriuretic Factor↗

The distal radio ulnar joint. The influence of geometry and ligament on simulated Colles' fracture. An experimental study.

In five fresh frozen arm specimens Colles' fracture was simulated by a dorsal wedge osteotomy of the distal radius. A spring load was applied to the cortex of the distal radius fragment exerting a constant traction force in proximal direction. The distal radius fragment showed minimal dorsal angulation as the forearm was positioned in neutral or pronation, assuming the distal radio ulnar joint including its radio ulnar ligament was kept intact. As the forearm was moved into supination the distal fragment angulated dorsally to close the dorsal open gap in spite of the ligament being intact. When the radio ulnar ligament was detached the stability was however lost in any forearm position. The result supports the concept of immobilizing a satisfactorily reduced Colles' fracture in neutral position, possibly in slight pronation but never in supination.

Adult↗

Capsulotomy of the distal radio ulnar joint.

In 18 patients, of whom the majority had sequelae after fractures to the distal radius, a capsulotomy of the distal radio ulnar joint was performed. Their main complaints were painful restricted forearm rotation combined with reduced grip strength. All patients were examined at least one year after surgery. 15 had improved forearm rotation and reduced pain while 14 had improved grip strength. It is concluded that capsulotomy of the distal radio ulnar joint might be effective treatment in cases of restricted painful forearm rotation after injuries to the distal radio ulnar joint.

Adolescent↗

Survival improvement with combined radio-chemotherapy in the primary central nervous system lymphomas.

The benefits of radio-chemotherapy in HIV-negative primary central nervous system (CNS) lymphomas were analyzed in 40 patients, who received radiotherapy to the brain or craniospinal axis with the total dose of 4460-5940 cGy to the primary tumor. Radiotherapy was followed by systemic chemotherapy, mainly with the cyclophosphamide, doxorubicin, vincristine and prednisolone (CHOP) regimen, in 16 of the patients. Follow-up ranged from four to 95 months with a median of 15 months. The relapse rate was 72.5%, and 83% of the relapses occurred within the radiation field. Median survival was 19 months and the two-year survival rate was 41%. Survival was significantly influenced by treatment method and radiation dose when measured by univariate analysis; median survival and the two-year survival rate was 29 months and 63% after radio-chemotherapy, while 13.5 month and 29% after radiotherapy alone (p= 0.027), and 22 months and 49% with doses of 50 Gy or more, but 12.5 months and 13% with doses less than 50 Gy (p=0.009). However, statistical significance was lost in multivariate analysis. These results might suggest the short-term efficacy of radio-chemotherapy, however, cautious observation is needed to confirm long-term effects.

Adolescent↗

Roles of nibrin and AtM/ATR kinases on the G2 checkpoint under endogenous or radio-induced DNA damage.

Checkpoint response to DNA damage involves the activation of DNA repair and G2 lengthening subpathways. The roles of nibrin (NBS1) and the ATM/ATR kinases in the G2 DNA damage checkpoint, evoked by endogenous and radio-induced DNA damage, were analyzed in control, A-T and NBS lymphoblast cell lines. Short-term responses to G2 treatments were evaluated by recording changes in the yield of chromosomal aberrations in the ensuing mitosis, due to G2 checkpoint adaptation, and also in the duration of G2 itself. The role of ATM/ATR in the G2 checkpoint pathway repairing chromosomal aberrations was unveiled by caffeine inhibition of both kinases in G2. In the control cell lines, nibrin and ATM cooperated to provide optimum G2 repair for endogenous DNA damage. In the A-T cells, ATR kinase substituted successfully for ATM, even though no G2 lengthening occurred. X-ray irradiation (0.4 Gy) in G2 increased chromosomal aberrations and lengthened G2, in both mutant and control cells. However, the repair of radio-induced DNA damage took place only in the controls. It was associated with nibrin-ATM interaction, and ATR did not substitute for ATM. The absence of nibrin prevented the repair of both endogenous and radio-induced DNA damage in the NBS cells and partially affected the induction of G2 lengthening.

Ataxia Telangiectasia Mutated Proteins↗

[Radio-chemotherapy of locally advanced head and neck cancer, providing tissue and organ protection]

PURPOSE: the study of the effect of Amifostine in reducing acute mucositis, xerostomia and late xerostomia emerging in the course of locally advanced head and neck cancer radio-chemotherapy. METHODS: Starting in 1999 we have conducted radio-chemotherapy treatment on 7 patients with or without Amifostine protection, each receiving 60 Gy (2 Gy a day/5 fractions a week) loco-regional irradiation. From the first to the fifth day and from the twenty-first to the twenty-fifth day prior to irradiation they were given a 70 mg/m(2) Carboplatin treatment. In the Amifostine group, on days 1-5 and 21-25 300 mg/m(2) and on days 6-20 and 26-30 200 mg/m(2) Amifostine therapy was given prior to the radio- and chemotherapy. RESULTS: In the course of the trial we did not find any haematologic side effects, or side effects directly connected to the Amifostine, which would have required suspension of the therapy. In the active phase, mucositis of Grade 1-2 was detected 1-2 weeks later than in the control group, in contrast to the mucositis of Grade 2-3 in the other arm. Global oral discomfort associated with acute xerostomia was of Grade 4-6 on a linear scale of ten, compared with Grade 7-8 on the active line. We had similar results when testing the symptoms directly connected with late xerostomia. Unstimulated and stimulated saliva production doubled following the Amifostine treatment. CONCLUSION: Despite the small pool of patients we have the impression that Amifostine can effectively reduce the severity of acute mucositis, xerostomia and late xerostomia.

Journal Article↗

[Radio-guided surgery with MIBG in a case of abdominal neuroblastoma].

Radio-guided surgery is a new technique which can provide benefits for pediatric oncology, as in our patient with neuroblastoma in stage IV, that after a chemotherapy, surgical, radiotherapy and autologous bone marrow transplant treatment kept showing, at 2 years, residual tumoral fragments and increase of catecholamines. Radio-guided surgery allowed an easy and exact location. This technique decreases surgery time and let us find residual tumoral tissue no matter how small. With radio-guided surgery we can obtain higher survival and even cure the patient.

3-Iodobenzylguanidine↗

Surgical and immediate post-release mortality of harlequin ducks (Histrionicus histrionicus) implanted with abdominal radio transmitters with percutaneous antennae.

Radiotelemetry is an essential tool in the study of free-ranging bird populations, and a variety of transmitter-attachment methods have been developed. A promising new method is abdominal implantation of a transmitter with a percutaneous antenna. Researchers using this technique should be concerned about and aware of mortality during surgery and during the immediate post-release period (the 14-day period following surgery). Of 307 radio-implant surgeries performed between 1995 and 1997 in harlequin ducks (Histrionicus histrionicus), 7 (2.3%) deaths were documented during surgery or anesthetic recovery. Of 295 birds released with implanted radios, 10 (3.4%) died during the immediate post-release period. Modifications to anesthetic procedures used in the 204 surgeries performed in 1996 and 1997 reduced mortality to 1.5% during surgery and 1.5% during the immediate post-release period. Anesthetic modifications included intubation of all birds, placement of birds on an elevated platform that allowed the head to rest at a level lower than the body during surgery, placement of a heated water blanket under the birds during surgery, monitoring of body temperature, and use of electrocardiogram and Doppler ultrasound to monitor heart rates and arrhythmias. Low levels of mortality associated with abdominal implantation of radio transmitters may be unavoidable, but mortality can be minimized with adjustments to anesthetic technique.

Alaska↗

[Cytoprotection with amifostine in radiotherapy or radio-chemotherapy of head and neck tumors].

BACKGROUND: A considerable amount of experimental and clinical data prove the cytoprotective effect of amifostine on normal tissue exposed to different types of antineoplastic treatments. The present study examines its influence on the short-term toxicity of either radiotherapy alone or combined radio-chemotherapy in patients with advanced head and neck cancer. PATIENTS AND METHODS: Twenty-three patients with advanced head and neck cancer, mainly Stage III and IV, were treated with preoperative radiation (n = 1), pre- as well as postoperative radiotherapy (n = 5), postoperative radiation (n = 9) or combined postoperative radio-chemotherapy (n = 6). Before each radiation application a total dose of 500 mg amifostine was administered intravenously over 15 minutes. The documentation of this unselected patient group was compared retrospectively to a historical control group comprising 17 patients. RESULTS: In 15 patients (65%) of the amifostine group, therapy induced side effects such as mucositis and dermatitis of WHO Grade < or = 2 were detected, requiring interruptions of the radiotherapy (mean: 6.5, maximum 17 days). No mucosa or dermatologic toxicity of WHO Grade 3 or 4 was observed in this group. Significantly more acute toxicity was detected in the historical control group. Stomatitis or epitheliolysis of WHO Grade 3 occurred in 7 patients (41%). The side effects induced by the antineoplastic therapy caused an interruption of treatment in 15 patients (88%) (mean: 16, maximum 40 days; p = 0.0016). CONCLUSION: The application of amifostine before each radiation treatment seems to result in a distinct reduction of short-term toxicity of radiotherapy or combined radio-chemotherapy in patients with head and neck cancer, allowing for a better adherence to the planned radiation time schedule.

Adult↗

The International Radio Medical Centre (C.I.R.M.): an organization providing free medical assistance to seafarers of any nationality world wide.

The International Radio Medical Centre (Centro Internazionale Radio Medico, C.I.R.M.) was founded in 1935 with the purpose of giving radio medical advice to ships on any nationality navigating on all seas of the world. The Centre has its headquarters in Rome, and its medical services are completely free of charge. They also include arrangements for the transfer, if necessary, of a patient to a ship with a doctor on board or if the distance allows it, to evacuate the patient for hospitalization. Requests for medical advice reaching C.I.R.M. are handled by doctors on continuos duty at the C.I.R.M. headquarters. These doctors advice on the appropriate treatment and keep in contact with every ship that has asked for assistance, following up the progress of the patient until his recovery or evacuation to the hospital on shore.

Global Health↗