Final report of a phase I/II trial of hyperfractionated and accelerated hyperfractionated radiation therapy with carmustine for adults with supratentorial malignant gliomas. Radiation Therapy Oncology Group Study 83-02

BACKGROUND

Efforts to improve local control and survival by increasing the dose of once-daily radiation therapy beyond 70 Gray (Gy) for patients with malignant gliomas has yet been unsuccessful. Hyperfractionated radiation therapy (HF) should allow for delivery of a higher total dose without increasing normal tissue late effects, whereas accelerated hyperfractionated radiation therapy (AHF) may minimize tumor repopulation by shortening overall treatment time. The Radiation Therapy Oncology Group (RTOG) conducted a randomized Phase I/II study of escalating doses of HF and AHF either carmustine (bis-chlorethyl nitrosourea [BCNU]) fro adults with supratentorial glioblastoma multiforme (GBM) or anaplastic astrocytoma (AA). Primary study endpoints were overall survival and acute and chronic treatment-related toxicity.

METHODS

From 1983 to 1989, 786 patients with supratentorial gliomas (81% with GBM and 19% with AA) were stratified by histology, age, and performance status and randomized to receive partial brain irradiation, utilizing either HF (1.2 Gy twice daily to doses of 64.8, 72, 76.8, or 81.6 Gy) of AHF (1.6 Gy twice daily to doses of 48 or 54.4 Gy). All patients received carmustine. The distinction of pronistic factors was similar on all arms.

RESULTS

There were 747 eligible and analyzable patients among 786 enrolled patients (95%). Two patients had a Grade 5 and 65 patients had a Grade 4 chemotherapy toxicity. Two patients in the 81.6 Gy arm experienced late Grade 4 radiation toxicity and there was 1 late radiation-associated death in the 54.4 Gy arm. The rate of Grade 3 of worse radiation toxicity at 5 years, calculated by the delivered does level, was 3% in the lowest total dose arms (48 and 54.4 Gy), 4% in the intermediate dose arms (64.8 and 72 Gy), and 5% in the highest dose arms (76.8 and 81.6 Gy) (p = 0.54). Survival rates at 2 and 5 years were: 21% and 11%, and 4%, respectively, for GBM patients. There were no significant differences between the treatment arms with regard to median survival time (MST), when analyzed by the originally assigned dose. The MST for all patients varied between 10.8 months and 12.7 months (P = 0.59); between 9.6 months and 11 months for patients with GBM (P = 0.43); and between 30.4 months and 85.8 months for patients with AA (P = 0.78). Analysis of the survival rates for all patients by dose received rather than by dose assigned revealed a 14% 5-year survival rate for the lower HF doses (64.8 and 73 Gy), 11% for the higher doses (76.8 and 81.6 Gy), and 10% for the AHF doses (48 and 54.4 Gy) (P = 0.1). The subgroup a AA patients had a better MST (49.9 months) in the lower received HF doses than in the higher HF doses (34.6 months) (P = 0.35). In contrast, GM patients who received the higher HF doses had survival superior to the patients in the AHF arms (MST of 11.6 months and 10.2 months, respectively, P = 0.04).

CONCLUSIONS

The use of HF with BCNU and dose escalation up to 81.6 Gy is both feasible and tolerable, although late toxicity increases slightly with increasing dose. The best MST with the least toxicity were observed for AA in the lower received HF doses (72 and 64.8 Gy). Accordingly, 72 Gy in two 1.2 Gy fractions was used as the investigational arm of a completed Phase III trial (RTOG 90-06). In contrast, for GBM patients, longer survival times were noted in the higher received HF doses (78.6 and 81.6 Gy), suggesting the role for further dose escalation. The low toxicity rate with AHF arms suggest that further dose escalation is possible and is currently occurring in RTOG 94-11.

Polymorphism in the LMP2 gene influences disease susceptibility and severity in HLA-B27 associated juvenile rheumatoid arthritis

OBJECTIVE

To determine the potential contribution of the MHC class II region proteasome subunit gene, LMP2, to disease susceptibility, severity, and phenotype in patients with juvenile rheumatoid arthritis (JRA).

METHODS

A CfoI restriction site polymorphism in the coding region of the LMP2 gene was evaluated in 279 patients with JRA and 107 healthy controls of similar ethnicity. Patients were divided into 5 groups on the basis of clinical presentation; 46% had early onset pauciarticular disease, 10% early onset polyarticular, 10% late onset pauciarticular, 20% late onset polyarticular, and 11% systemic onset arthritis. The influence of this LMP2 polymorphism on susceptibility to disease, clinical subtype of disease at onset (age and number of joints involved), progression and severity of joint disease (pauci to polyarticular course and radiographic changes), and occurrence of inflammatory eye disease was evaluated.

RESULTS

Comparison of genotypes revealed a significantly increased prevalence of homozygosity for the LMP2 B allele (LMP2 BB genotype) in patients who were older (> or = 6 years) at onset of disease (65%, p < 0.05), particularly in those with pauciarticular (71%) involvement at presentation (p < 0.05), compared to controls (51%). The BB genotype was also more prevalent in patients with a polyarticular course, either from onset (63%) or those who progressed from pauciarticular disease (69%), compared with controls, (p = 0.05 and < 0.05, respectively). Stratification for HLA-B27 and DR4, the HLA alleles most frequently associated with late onset pauciarticular and late onset polyarticular JRA, respectively, revealed a persistent effect of LMP2 BB homozygosity on disease susceptibility and phenotype that remained statistically significant in HLA-B27 positive children, and was not due to linkage disequilibrium.

CONCLUSION

We show that homozygosity of the B allele of the proteasome subunit LMP2 increases susceptibility to certain subgroups of JRA, and influences the phenotype of disease, predisposing to more progressive and severe articular disease.

Stage I and II Hodgkin's disease in the pediatric population. Long-term follow-up of patients staged predominantly clinically

Between January 1, 1970, and December 31, 1990, 42 consecutive pediatric patients were treated at the Medical College of Wisconsin Affiliated Hospitals for early-stage Hodgkin's disease. Thirty patients were clinically staged. Twelve underwent staging laparotomy as a part of staging work-up. Thirty-one patients were treated with radiation therapy (RT) alone. Eleven were treated with combined chemotherapy and RT. For the entire group, overall survival at 5, 10, and 15 years was 98, 98, and 92%, respectively. Disease-free survival was 86, 86, and 79, respectively. There was no significant difference in overall survival or disease-free survival comparing clinically versus pathologically staged patients. There was a trend toward improved disease-free survival favoring pathologically staged patients; however, this difference did not reach statistical significance (p = 0.07). The long-term results of this series fail to show statistically significant superior disease-free or overall survival with surgical staging.

T-cell receptor BV6S1 null alleles and HLA-DR1 haplotypes in polyarticular outcome juvenile rheumatoid arthritis

JRA is a complex of disease subtypes which are normally identified by clinical features such as age of onset and extent of joint involvement both at onset and during the course of the disease. We previously identified an association between TCR BV6S1 null allele and one subgroup of early-onset pauciarticular patients positive for HLA-DQA1*0101, an HLA haplotype predisposing to a polyarticular course of the disease. In this report we extend this observation by identifying an increased prevalence of this nonfunctional or null allele in the patients with a polyarticular disease course regardless of the mode of onset. This increase was most prominent in clinical subsets that have early onset of the disease and a polyarticular outcome. In one clinical group, stratification of patients by the HLA allele DQA1*0101 strengthened the association considerably. This implies that there is an increased genetic load defined by specific alleles of both MHC and TCR genes.

Pediatric sensorineural hearing loss after temporal bone radiation

In adults, sensorineural hearing loss (SNHL) resulting from megavoltage temporal bone radiation therapy (RT) is dose dependent. A review of the literature reveals only two cases of pediatric SNHL after RT without chemotherapy. This report presents four cases of late onset, asymmetric SNHL after RT in children treated for posterior fossa tumors. The children were treated with surgical resection of the tumor, followed by RT of 50 to 54 gray and no chemotherapy. These children, without evidence of tumor recurrence, developed severe SNHL 18 to 36 months after the completion of RT. Although no definite audiometric pattern was seen, most of the patients had a predominately high frequency SNHL in the poorer hearing ear, and fluctuant hearing in the better ear, without evidence of osteoradionecrosis or otitic infection. A review of the literature suggests that injury to the outer hair cells and cochlear neurons of the basal turn of the cochlea are possible sources for the hearing loss. Pretreatment audiologic evaluation as well as a minimum of 3 years of evaluations following RT would be prudent.

Functional measures in children with rheumatic diseases

The measurement of function in children with rheumatic diseases is an intimate part of not only the initial diagnostic work-up, but also of every clinic visit during the course of these chronic diseases. This article focuses on the development of specific and general instruments used to systematically measure function and thus, outcome of the rheumatic diseases and their treatments. Reference is made to instruments developed for use in the general pediatric and adult rheumatology population as a basis for the discussion of the instruments in use in pediatric rheumatology. Specifically, the dimensions of physical function, psychosocial impact, economic impact and quality of life are addressed.

Central pathology review in clinical trials for patients with malignant glioma. A Report of Radiation Therapy Oncology Group 83-02

BACKGROUND

Confounding biologic factors, including histologic grade, may influence the outcome of adult patients with malignant gliomas more than may modifications in therapeutic approach. Any clinical trial design for malignant gliomas in adults must account for such biologic factors, including the accurate identification of the two histologic subgroups astrocytoma with anaplastic foci (AAF) or glioblastoma multiforme (GBM), which are associated with distinctly different survival outcomes. This paper examines the need for a central pathology review before entry of patients in cooperative group clinical trials stratified by histologic grade.

METHODS

Pathology slides from Radiation Therapy Oncology Group (RTOG) trial 83-02, a randomized Phase II study of hyperfractionated and accelerated hyperfractionated radiation therapy and carmustine for malignant gliomas, provided 747 analyzable cases, with 680 (91%) available for central pathology review. This review was performed by a single pathologist according to RTOG/Eastern Cooperative Oncology Group histopathologic criteria. The kappa statistic was used to measure agreement between the institutional and central classification of AAF and GBM. The influence of misclassification was examined using computer simulation of varying clinical trial sizes (n = 25, 50, or 200). The effect on the statistical power of trials (n = 200) with varying mixtures of AAF and GBM tumors was investigated using computer simulations.

RESULTS

Of 159 tumors classified as AAF by institutional pathology review, only 66% (105) were classified as AAF (AAF/AAF) by central review, and 54 of these cases (34%) were classified as GBM (GBM/AAF), whereas 96% (501) of 521 institutionally classified as GBM (GBM/GBM) were similarly classified by central review. Computer simulations demonstrated a 59% underestimation in the median survival (1.82 vs. 4.49 years) for trials of patients with institutionally defined AAF compared to patients with centrally defined AAF in studies of 200 patients, resulting from the addition of poor prognosis of GBM in the trial. Misclassification can also substantially reduce the statistical power of a clinical trial. In one of the simulation studies, statistical power was reduced from 65% to 14% if 50% of the patients were to receive an inaccurate histologic classification. Even greater losses in power are possible in many plausible clinical settings.

CONCLUSIONS

This examination of a central versus an institutional pathology review demonstrates a low level of agreement on AAF classification and a high level of concordance on GBM classification. The results indicate the need to adjust sample size for trials of both AAF and GBM tumors to have adequate statistical power. A central pathology review remains essential for trial entry for patients with AAF and could be omitted for trials enrolling patients with GBM only.

Quality-adjusted survival analysis of malignant glioma. Patients treated with twice-daily radiation (RT) and carmustine: a report of Radiation Therapy Oncology Group (RTOG) 83-02

PURPOSE

To quantify the quality of life of malignant glioma patients treated on a randomized Phase I/II trial of twice-daily radiation therapy (RT) and carmustine, using a modified quality adjusted survival (QAS) model, and to compare the QAS among assigned treatment arms.

MATERIALS AND METHODS

The Radiation Therapy Oncology Group (RTOG) accrued 786 malignant glioma patients to a Phase I/II randomized dose escalation trial of twice-daily RT with carmustine from 1983 to 1989. Patients were randomized to one of four arms of hyperfractionated RT in 1.2 Gy twice daily (BID) fractions (64.8 Gy, 72.0 Gy, 76.8 Gy, or 81.6 Gy) or to either of two accelerated hyperfractionated RT arms in 1.6 Gy BID fractions (48.0 or 54.4 Gy). Although preliminary toxicity and survival data have been published, little information is available regarding the quality of these patients' lives during and following such therapy. QAS is a refinement of the methodology for assessing survival quality among breast cancer patients receiving adjuvant chemotherapy. The QAS method allows for inclusion of both improvement and decline in neurologic functional status. Patients were scored by the presence or absence of 15 neurologic signs and symptoms at on-study and at every follow-up. Within each category were gradations of severity, with the quality survival time (Q-TIME) adjusted according to any changes in these neurologic findings. The summation of all changes in signs and symptoms were weighted by 1/15th and incorporated into the QAS model as QAS = Q-TIME-TOX-RRX. TOX was the time spent with treatment-related toxicities, and RRX was the time spent in recovery from subsequent therapy.

RESULTS

Of 747 evaluable patients, the average QAS time was 18.5 months. The average QAS for the hyperfractionated arms of 64.8 Gy, 72.0 Gy, 76.8 Gy, and 81.6 Gy were 15.6, 20.8, 10.0, and 13.7 months, respectively. For the accelerated hyperfractionated RT arms of 48.0 and 54.4 Gy, the average QAS times were 13.1 and 13.4 months. The QAS time of the 72.0 Gy arm was significantly longer than that of all other groups, except the 64.8 Gy arm. As expected, the QAS times were strongly discriminated by both age and Karnofsky Performance Scores (KPS) (p < 0.001). Younger patients and patients with high KPS benefited most from assignment to the 72.0 Gy arm; QAS time was not significantly longer in any treatment arm among patients over age 50 or with KPS scores of 80 or less.

CONCLUSIONS

This quality-adjusted survival methodology can be successfully applied to malignant glioma patients and permits a quantitative assessment of the influence of investigational therapies on patient quality of life. This analysis confirms the potential benefit of intermediate dose (72.0 Gy) hyperfractionated RT for selected malignant glioma patients.

Echographic monitoring of response of extraocular muscles to irradiation in Graves' ophthalmopathy

PURPOSE

Confirmation of the efficacy of orbital irradiation in Graves' ophthalmopathy is needed due to the unpredictable natural history of the disease, the variation in individual clinical presentations, the contribution of other simultaneous treatments, and the lack of controlled studies using objective criteria to classify and assess response over time. Orbital echography before and at select intervals following orbital irradiation is proposed as an objective parameter of tissue response to orbital irradiation over time.

METHODS AND MATERIALS

From January, 1983 to September, 1993, 55 patients with progressive Graves' ophthalmopathy underwent 20 Gy retrobulbar irradiation. On retrospective review, standardized orbital echography was performed randomly prior to irradiation in 37 of the 55 patients to assess the acoustic characteristics of the extraocular muscles and to quantitate their individual and summed diameters. Twenty-one patients had at least one follow-up echographic evaluation at random intervals of 0 to 27.5 months following completion of irradiation. Twelve patients received steroids before or during irradiation, which were tapered in proximity to completion of radiation. Follow-up ranged from 2 to 65 months with the majority followed at least 6 months (18 patients).

RESULTS

Of the 21 patients with serial studies, 18 showed an interval decrease in individual and summed muscle size over time and return of symmetry. Interval improvement was documented as early as the 1 month follow-up study, with continued improvement seen during the 3-9-month studies, with stability typically achieved within 12 months. One patient had further changes between the 21 and 27.5 month follow-up studies. Exacerbation of disease was, however, echographically demonstrated in three patients at 6.5, 8.5, and 13 months. Follow-up studies in two of these patients again revealed improvement, one following tapered steroids. The third patient required orbital decompression.

CONCLUSION

Objective parameters of response are needed to document both the immediate and long-term outcome of orbital irradiation on the course of Graves' ophthalmopathy and confirm its efficacy. Serial echography is proposed as a new technique for providing parameters to judge response.

Pancreatitis associated with brain tumor therapy

PURPOSE

Four children with prolonged emesis during brain tumor therapy were diagnosed with pancreatitis.

PATIENTS AND METHODS

All were exposed to medications or radiotherapy that potentially contributed to pancreatitis.

CONCLUSIONS

Because recognition of pancreatitis may necessitate changes in supportive care, pancreatitis should be included in the differential diagnosis of vomiting in this population.

Prostate cancer: are racial differences in clinical stage and survival explained by differences in symptoms?

PURPOSE

To better understand racial differences in data for patients referred for definitive treatment of biopsy-proved adenocarcinoma of the prostate gland.

MATERIALS AND METHODS

Two groups of patients were defined for further analysis. Group 1 comprised all patients who received definitive external beam irradiation of prostatic carcinoma; group 2 comprised all patients with prostatic carcinoma referred between January 1988 and December 1992 for examination at the first clinical indication of adenocarcinoma of the prostate. All patients were evaluated for age, race (black vs white), differentiation of tumor, date of diagnosis, and clinical stage.

RESULTS

In group 1, black patients were significantly younger and presented with disease at higher clinical stage but equivalent grade and survival compared with white patients. In group 2, black patients were significantly younger and had similar differentiation of tumor but with significantly higher clinical stage compared with white patients and more often had obstructive symptoms and less often had been screened for elevated prostate-specific antigen levels.

CONCLUSION

Black patients should undergo earlier screening for prostate cancer.

Relaxation of guinea-pig trachea by cyclic AMP phosphodiesterase inhibitors and their enhancement by sodium nitroprusside

1. The effects of agents that elevate either cyclic AMP (the phosphodiesterase (PDE) III inhibitor siguazodan, salbutamol) or cyclic GMP (sodium nitroprusside (SNP)) on the relaxant activity of the PDE IV inhibitor, rolipram, were investigated in carbachol (0.1 microM) precontracted guinea-pig tracheal sheets. 2. Rolipram, siguazodan and SNP caused concentration-related reductions in tone of tissues precontracted with 0.1 microM carbachol (EC50 values 12.5; 2.73 and 0.35 microM respectively). Whilst the concentration-response relationship for the PDE III inhibitor, siguazodan, was monophasic that of the PDE IV inhibitor, rolipram, was biphasic. 3. The relaxant activity of rolipram was markedly enhanced in the presence of 10 microM siguazodan (EC50 < 0.01 microM), 0.1 microM salbutamol (EC50 0.03 microM) and 0.3 microM SNP (EC50 0.03 microM). In contrast, the relaxant activity of siguazodan was unaffected by SNP and only modestly enhanced by rolipram (10 microM) and salbutamol (0.1 microM). 4. The relaxant activity of SNP was enhanced by the PDE V inhibitor SK&F 96231 (30 microM: EC50 0.06 microM) and rolipram (30 microM, EC50 0.08 microM) but was unaffected by 30 microM siguazodan. 5. At concentrations up to 10 microM, neither siguazodan nor rolipram elevated tracheal cyclic AMP levels. However, the combination of 10 microM rolipram and siguazodan caused a two fold increase in the cyclic AMP content (from 2.19 to 4.36 pmol cyclic AMP mg-1 protein). SNP (0.1-10 microM) failed to produce a significant increase in tracheal cyclic AMP levels. At 0.1 microM the effect of SNP on tracheal cyclic AMP levels was significantly (P < 0.05) increased in the presence of rolipram but not siguadozan. 6. The results indicate that the relaxant effects of rolipram are markedly enhanced by agents that inhibit PDE III activity or elevate cyclic GMP. They support the hypothesis that SNP potentiates the effects of rolipram via the inhibitory action of cyclic GMP on hydrolysis of cyclic AMP by PDE III. The findings also suggest that whilst PDE III may be more significant in regulating basal smooth muscle tone in the absence of any exogenous stimulus to cyclic AMP accumulation, PDE IV activity may be more tightly coupled to the pool of adenylyl cyclase stimulated by beta2-adrenoceptor agonists.

Pulmonary effects of type V cyclic GMP specific phosphodiesterase inhibition in the anaesthetized guinea-pig

1. We have investigated the bronchodilator potential of type V phosphodiesterase (PDE V) inhibitors in anaesthetized ventilated guinea-pigs using the potent and selective PDE V inhibitor, SK&F 96231. We have compared its activity to that of salbutamol, the PDE III inhibitors, siguazodan and SK&F 95654 and to the PDE IV inhibitor rolipram. 2. Administered as an i.v. infusion SK&F 96231 (0.6 and 1 mg kg-1 min-1, i.v.) caused a slowly developing inhibition of histamine (100 nmol kg-1, i.v.)-induced bronchoconstriction and elevated tracheal cyclic GMP levels in the anaesthetized guinea-pig. SK&F 96231 (0.1 and 0.3 mg kg-1 min-1, i.v.) was without effect on histamine-induced bronchoconstriction. In the presence of a sub-threshold infusion of SNP (0.1 mumol kg-1 min-1, i.v.) there was a marked enhancement of SK&F 96231-induced inhibition of histamine responses such that at infusion rates that were ineffective alone, SK&F 96231 caused a > 50% inhibition of histamine responses. The stimulation of tracheal cyclic GMP accumulation by SK&F 96231 was also potentiated. 3. Administered directly into the airway, SK&F 96231 (300 micrograms in 5 mg lactose carrier) was largely without effect on histamine-induced bronchoconstriction (4.9 +/- 1.9% inhibition). In the presence of SNP (0.1 mumol kg-1 min-1, i.v.) or isosorbide dinitrate (200 micrograms administered by insufflation into the trachea) there was a marked potentiation of the inhibitory activity of SK&F 96231 (40 +/- 4% and 62 +/- 1.8% respectively). 4. Salbutamol and rolipram (3-300 microg by insufflation) caused a dose-related inhibition of histamine responses with a maximum of 91 +/- 2% and 59 +/- 10% respectively. The PDE III inhibitor, siguazodan,was without effect on histamine responses but they were reduced (27.7 +/- 4.8% at 300 microg) by SK&F95654. There was a marked enhancement of the inhibitory activity of rolipram in the presence of SK&F 95654.5. We conclude that SK&F 96231 has weak anti-spasmogenic activity in the guinea-pig in vivo, we suggest that this is primarily a consequence of a low endogenous guanylate cyclase activity in the airway. The potentiation of the anti-spasmogenic activity of SK&F 96231 by SNP suggests that a combination of PDE V inhibitor and guanylate cyclase agonist might provide significant bronchodilator activity.6. We have established that PDE IV inhibitors are bronchodilators when administered directly into the airway of anaesthetized guinea-pigs but that PDE III inhibitors are only weakly active. The marked enhancement of the inhibitory activity of rolipram by the PDE III inhibitor, SK&F 95654, indicates that inhibitors of both PDE III and PDE IV might offer greater potential as bronchodilators than inhibitors of either isoenzyme alone.

Continuous split course irradiation for stage I and II Hodgkin's disease: 20 year experience at the Medical College of Wisconsin

Between January 1970 and December 1989, 153 consecutive patients with stage I or II Hodgkin's disease were treated at the Medical College of Wisconsin Affiliated Hospitals. Eighty-eight patients were clinically staged and 65 patients underwent staging laparotomy. Ninety-nine patients were treated using continuous split course irradiation (CSCI) technique. Overall survival (OS) at 5, 10, and 15 years was 89%, 79%, and 68%, respectively. Disease-free survival (DFS) at 5, 10, and 15 years was 75%, 72%, and 68%, respectively. No significant differences were found in OS or DFS when comparing pathologically and clinically staged patients or when comparing patients treated using CSCI with those treated with the standard technique. Patients treated using CSCI tended to complete therapy in a shorter time, without increased morbidity.

Inhibition of cyclic nucleotide phosphodiesterase by derivatives of 1,3-bis(cyclopropylmethyl)xanthine

Alkylation of the selective type IV phosphodiesterase inhibitor, 8-amino-1,3-bis(cyclopropylmethyl)-xanthine (1, BRL 61063), led exclusively to the N-7 substituted derivatives 2-9, which showed varying selectivities for the PDE type IV isoenzyme relative to PDE Va. The 4-methoxybenzyl derivative 6 in particular was a highly potent PDE Va inhibitor (IC50 0.14 microM) and showed a 24-fold selectivity for this isoenzyme relative to PDE IV. Sulfonation of 1 was more complex, with the product profile being highly dependent on the reaction conditions. As with alkylation, sulfonation at N-7 generally increased potency against PDE Va, especially in the aryl-containing moieties lacking strongly electron-withdrawing substituents (12, 15-17, 19). Bis-arylsulfonation at the exocyclic amino group generally reduced inhibitory potency against both PDE IV and Va. An 8-amidino compound 33, formed by the unusual reaction of 1 with N-methylpyrrolidinone in the presence of benzenesulfonyl chloride, had an IC50 value of 0.05 microM against PDE Va and is believed to be the most potent inhibitor of this isoenzyme reported. No correlation of PDE IV inhibition with displacement of [3H]rolipram from its high-affinity binding site was demonstrated. This suggests that either the catalytic site and the rolipram binding site are not the same or that PDE IV can exist in two conformations, only one of which binds to rolipram with high affinity, and that the compounds described vary in their selectivity for this isoform.

The role of photodynamic therapy in posterior fossa brain tumors. A preclinical study in a canine glioma model

Photodynamic therapy was studied in dogs with and without posterior fossa glioblastomas. This mode of therapy consisted of intravenous administration of Photofrin-II at doses ranging from 0.75 to 4 mg/kg 24 hours prior to laser light irradiation in the posterior fossa. Tissue levels of Photofrin-II were four times greater in the tumor than in the surrounding normal brain. Irradiation was performed using 1 hour of 500 mW laser light at a wavelength of 630 nm delivered through a fiberoptic catheter directly into the tumor bed via a burr hole. All animals receiving a high dose (4 or 2 mg/kg) of Photofrin-II developed serious brain-stem neurotoxicity resulting in death or significant residual neurological deficits. A lower dose (0.75 mg/kg) of Photofrin-II produced tumor kill without significant permanent brain-stem toxicity in either the control animals or the animals with cerebellar brain tumors receiving photodynamic therapy.

Phosphorylation of tau by cyclic-AMP-dependent protein kinase

Alzheimer's disease paired helical filaments contain abnormally phosphorylated tau (PHF-tau) which has reduced electrophoretic mobility on sodium dodecyl sulphate polyacrylamide electrophoresis. We have investigated the effects of cyclic-AMP-dependent protein kinase (PKA) on recombinant human tau isoforms and two recombinant tau fragments. PKA phosphorylated tau and reduced its electrophoretic mobility, phosphorylation towards the C-terminus of tau having a major influence on this property. Substitution of serine396 (phosphorylated in PHF-tau) or serine416 (phosphorylated by calcium/calmodulin kinase II) by alanine demonstrated that these are not major sites for PKA phosphorylation. Although the phosphorylated forms of tau generated by PKA are not identical to those of PHF-tau, PKA may be involved in the generation of PHF-tau in Alzheimer's disease via phosphorylation of additional, as yet unidentified, sites on tau.

Comparison of the effect of isobutylmethylxanthine and phosphodiesterase-selective inhibitors on cAMP levels in SH-SY5Y neuroblastoma cells

A comparison of the effects of various phosphodiesterase (PDE) inhibitors upon cellular cAMP levels was undertaken in human neuroblastoma SH-SY5Y cells. When inhibitors such as rolipram and Ro 20 1724 (selective for the low Km cAMP-specific PDE) were used, cAMP levels were seen to rise dramatically under basal (< or = 60 fold) or forskolin-stimulated (< or = 200 fold) conditions. However, the non-selective PDE inhibitor isobutylmethylxanthine (IBMX) was 7-18% as effective as these other agents even at 1 mM. The poor efficacy of IBMX was not attributable to concomitant increases in cGMP, to alterations in cAMP egress or to a lack of sensitivity of the cellular PDEs to IBMX inhibition. In additivity experiments, IBMX potently and rapidly reduced cAMP that had accumulated after rolipram treatment. The fact that the agonist 2-chloroadenosine can enhance cAMP accumulation in these cells, and that cAMP elevated by rolipram or forskolin can be reduced by adenosine deaminase and theophylline suggest that cell-derived adenosine enhances cAMP in these cells in an autocrine fashion. Since IBMX is an adenosine receptor antagonist, it is suggested that its blockade of endogenous adenosine effects is at least partly responsible for its poor response when compared to other PDE inhibitors which are weaker adenosine receptor antagonists. These results forewarn against assuming that similar levels of cAMP accumulate after application of PDE inhibitors in these cells.

Vertebral artery injury during anterior decompression of the cervical spine. A retrospective review of ten patients

Ten patients who suffered iatrogenic injury to a vertebral artery during anterior cervical decompression were reviewed to assess the mechanisms of injury, their operative management, and the subsequent outcome. All had been undergoing a partial vertebral body resection for spondylitic radiculopathy or myelopathy (4), tumour (2), ossification of the posterior longitudinal ligament (1), nonunion of a fracture (2), or osteomyelitis (1). The use of an air drill had been responsible for most injuries. The final control of haemorrhage had been by tamponade (3), direct exposure and electrocoagulation (1), transosseous suture (2), open suture (1), or open placement of a haemostatic clip (3). Five patients had postoperative neurological deficits, but most of them resolved. We found direct arterial exposure and control to be safe, quick and reliable. Careful use of the air drill, particularly in pathologically weakened bone, as in infection or tumour, is essential. Arterial injury is best avoided by a thorough knowledge of the anatomical relationships of the artery, the spinal canal, and the vertebral body.

Central lymphatic irradiation for stage III nodular malignant lymphoma: long-term results

PURPOSE

To report the long-term results of central lymphatic irradiation for stage III nodular malignant lymphoma.

PATIENTS AND METHODS

Between 1969 and 1985, 34 patients (26 with nodular poorly differentiated lymphoma, four with nodular mixed lymphocytic/histiocytic lymphoma, and four with nodular histiocytic lymphoma) were treated with central lymphatic irradiation. Median age of the group was 51 years (range, 30 to 73). There were 15 men and 19 women. Staging work-up included a physical examination and bone marrow biopsy in all patients. Seventy-four percent had a lymphangiogram (LAG) and 44% a laparotomy (LAP). Eighty-two percent had either a LAP or a LAG. Thirty-two patients were Ann Arbor stage IIIA and two were stage IIIB. All patients received lymphatic irradiation that encompassed cervical, supraclavicular, axillary, mediastinal, paraaortic, mesenteric, pelvic, and femoral lymphatics to total doses ranging from 20 to 30 Gy in 1.0- to 1.8-Gy fractions. Waldeyer's ring was initially treated in 17 patients. Follow-up information is available on all 34 patients. Median follow-up is 9 years, 8 months (range, 15 to 244 months).

RESULTS

Life-table actuarial overall, disease-free, and cause-specific survival rates at 15 years are 28%, 40%, and 46%, respectively. Only one relapse was observed after 9 years. Disease-free survival was significantly improved in patients with five or fewer sites of involvement (P = .02). Age, sex, B symptoms, histology, and technique of irradiation were not prognostically significant. Salvage therapy, including further irradiation and/or chemotherapy, was delivered to 20 patients. Ten percent of these patients remain alive without evidence of disease. Toxicity data were available for the patients treated at the Medical College of Wisconsin (MCW). Radiation Therapy Oncology Group (RTOG) acute hematologic, gastrointestinal, and salivary toxicity scores were < or = 2 in 83% of patients. Late toxicity scores were < or = 2 in 96%. Persistent xerostomia was noted in 23% of patients who received initial treatment to Waldeyer's ring.

CONCLUSION

These results suggest that initial comprehensive central lymphatic irradiation may be the preferred approach to achieve a durable relapse-free interval for this group of patients.

Use of a community-based touch-screen public-access health information system

Meeting the demands of patients and the public for health information is now a recognised aim. Healthpoint is a community-based touch-screen public-access health information system which aims to make health information easily accessible by the public and to provide feedback information on this demand. We have assessed Healthpoint in an experiment in three parts. Part one was a survey of 13 Healthpoints for several weeks in various community sites in Glasgow, such as a shopping centre, supermarket, library, and pub, as well as health service sites such as out-patient department and general practice. The number of users and the topics chosen were recorded by the systems. Part two was a survey of ten Healthpoints in one town (Clydebank) over five months, which examined routine information recorded by the system, and interviews with an opportunistic sample of 300 weekday shoppers in the street and a random sample of 271 by telephone. Part three was a survey of one Healthpoint in a general practice for 36 weeks using routine recording by the system and a postal survey of a systematic sample of 250 attenders. Seventy five (25%) out of 300 in the street survey and 45 (22%) of the telephone sample who had visited a site where there was a Healthpoint had used it. Overall, 17% of the telephone sample had used it. Seventy three (27%) out of 200 general practice attenders had used Healthpoint.(ABSTRACT TRUNCATED AT 250 WORDS)

8-(4-Chlorophenyl)thio-cyclic AMP is a potent inhibitor of the cyclic GMP-specific phosphodiesterase (PDE VA)

8-(4-Chlorophenyl)thio-cyclic AMP (8-CPT-cAMP), extensively used as selective activator of cyclic AMP-dependent protein kinase, has been found to be a potent inhibitor of the cyclic GMP-specific phosphodiesterase (PDE VA). Indeed, 8-CPT-cAMP (IC50 = 0.9 microM) inhibited PDE VA with a potency identical to that of zaprinast. 8-CPT-cAMP was also metabolized by PDE VA at a rate half that of cyclic GMP. The cyclic GMP-inhibited phosphodiesterase (PDE III) (IC50 = 24 microM) and the cyclic AMP-specific phosphodiesterase (PDE IV) (IC50 = 25 microM) were also inhibited by 8-CPT-cAMP. In contrast, most of the other cAMP-derivative studies showed little inhibition of any phosphodiesterase isoenzyme. These observations provide further reasons why the mechanism of the physiological effects of 8-CPT-cAMP should be interpreted with caution.