Is walking netball an effective, acceptable and feasible method to increase physical activity and improve health in middle- to older age women?: A RE-AIM evaluation.

BACKGROUND: Physical activity is a modifiable risk factor for health and wellbeing, all-cause mortality and healthy aging. However, for middle- to older-age females less is known about the benefits of sports participation on these outcomes. Further, the acceptability and feasibility of setting-up, implementing and maintaining sports-based programmes for an aging population is an understudied area of inquiry. The current study used the RE-AIM framework to investigate a nationwide Walking Netball (WN) programme. METHODS: The evaluation used a mixed-methods approach incorporating a multiple-baseline study, quasi-experimental study, programme monitoring data and qualitative studies to evaluate the programme in the Women's Institutes (WI) in England. Data were analysed using multilevel growth modelling, mixed-design ANOVAs, multilevel regression, t-testing, and thematic analysis. Data were triangulated to address each dimension of the RE-AIM framework. FINDINGS: The programme reached 1.4% (n = 3148) of the WI population across 82.0% of WI regions in England and attracted inactive members at risk of ill-health. WN contributed to adaptations in physical function, mental health and wellbeing, social isolation, quality of life and increased physical activity. The adoption of the programme was successful with 87.7% WN groups' maintaining participation beyond the 20-session initial delivery phase. Adoption was effective because of its set-up, peer-mentorship and long-term delivery; these factors likewise shaped implementation. Adapting and tailoring WN to the varying characteristics of participants within the WI and the facilities available, along with training delivery staff and providing resources are key programme components. The Walking Netball programme can be maintained through promotion within the local community, sustainable funding, inter-WI competitions, festivals and networks, multiple-hosts and continued host development. CONCLUSIONS: WN was found to be an acceptable, feasible and effective intervention to increase physical activity and improve health in middle- to older- aged women. Future programmes may consider adapted styles of set-up and delivery. These include adapting to people, places and spaces through personalised support and providing a range of resources. Future designs may seek to understand how participation can contribute to healthy aging through longitudinal research beyond 12-months. STUDY REGISTRATION: The evaluation protocol was published in Open Science Framework in December 2018 prior to follow-up data collection being collected ( https://www.osf.io/dcekz ). Date of registration: 17 December 2018.

Impact of third- and fourth-degree perineal tears at first birth on subsequent pregnancy outcomes: a cohort study.

OBJECTIVE: To investigate, among women who have had a third- or fourth-degree perineal tear, the mode of delivery in subsequent pregnancies as well as the recurrence rate of third- or fourth-degree tears. DESIGN: A retrospective cohort study of deliveries using a national administrative database. SETTING: The English National Health Service between 1 April 2004 and 31 March 2012. POPULATION: A total of 639,402 primiparous women who had a singleton, term, vaginal live birth between April 2004 and March 2011, and a second birth before April 2012. METHODS: Multivariable logistic regression models were used to estimate odds ratios, adjusted for other risk factors. MAIN OUTCOME MEASURES: Mode of delivery and recurrence of tears at second birth. RESULTS: The rate of elective caesarean at second birth was 24.2% for women with a third- or fourth-degree tear at first birth, and 1.5% for women without (adjusted odds ratio, aOR 18.3, 95% confidence interval, 95% CI 16.4-20.4). Among women who had a vaginal delivery at second birth, the rate of third- or fourth-degree tears was 7.2% for women with a third- or fourth-degree tear at first birth, compared with 1.3% for women without (aOR 5.5, 95% CI 5.2-5.9). CONCLUSIONS: The risk of a severe perineal tear is increased five-fold in women who had a third- or fourth-degree tear in their first delivery. This increased risk should be taken into account when decisions about mode of delivery are made.

Third- and fourth-degree perineal tears among primiparous women in England between 2000 and 2012: time trends and risk factors.

OBJECTIVE: To describe the trends of severe perineal tears in England and to investigate to what extent the changes in related risk factors could explain the observed trends. DESIGN: A retrospective cohort study of singleton deliveries from a national administrative database. SETTING: The English National Health Service between 1 April 2000 and 31 March 2012. POPULATION: A cohort of 1 035 253 primiparous women who had a singleton, term, cephalic, vaginal birth. METHODS: Multivariable logistic regression was used to estimate the impact of financial year of birth (labelled by starting year), adjusting for major risk factors. MAIN OUTCOME MEASURE: The rate of third-degree (anal sphincter is torn) or fourth-degree (anal sphincter as well as rectal mucosa are torn) perineal tears. RESULTS: The rate of reported third- or fourth-degree perineal tears tripled from 1.8 to 5.9% during the study period. The rate of episiotomy varied between 30 and 36%. An increasing proportion of ventouse deliveries (from 67.8 to 78.6%) and non-instrumental deliveries (from 15.1 to 19.1%) were assisted by an episiotomy. A higher risk of third- or fourth-degree perineal tears was associated with a maternal age above 25 years, instrumental delivery (forceps and ventouse), especially without episiotomy, Asian ethnicity, a more affluent socio-economic status, higher birthweight, and shoulder dystocia. CONCLUSIONS: Changes in major risk factors are unlikely explanations for the observed increase in the rate of third- or fourth-degree tears. The improved recognition of tears following the implementation of a standardised classification of perineal tears is the most likely explanation.

Health care providers' attention to food insecurity in households with children.

OBJECTIVE: To determine the extent to which physicians and nurse practitioners monitor household food insecurity (FI) of families with children, and to examine factors that influence FI monitoring. METHOD: A 2007 mail survey of family practice and pediatric physicians and nurse practitioners in the Portland, Oregon, region yielded 186 responses. Factor analysis was used to identify barriers to asking about FI. Regression analysis was used to determine whether monitoring of household food status was predicted by those barriers, attentiveness to potential FI indicators, and other variables. RESULTS: Most respondents did not routinely inquire about household FI during clinic visits. However, 88.8% expressed willingness to use a standardized screening question, if available. Monitoring of household food nutritional quality was significantly predicted by one of three identified barriers (providers' time availability). Monitoring of household food sufficiency was predicted by years in practice, attentiveness to FI indicators, and the remaining two identified barriers (inadequate knowledge about FI, discomfort in discussing FI). CONCLUSION: Routine monitoring of patients' household FI by health care providers is an underutilized strategy for reducing this condition, which poses serious risks to children's health and development. Addressing providers' concerns and introducing standardized screening procedures can increase their monitoring behaviors.

Short KIR haplotypes in pygmy chimpanzee (Bonobo) resemble the conserved framework of diverse human KIR haplotypes.

Some pygmy chimpanzees (also called Bonobos) give much simpler patterns of hybridization on Southern blotting with killer cell immunoglobulin-like receptor (KIR) cDNA probes than do either humans or common chimpanzees. Characterization of KIRs from pygmy chimpanzees having simple and complex banding patterns identified nine different KIRs, representing seven genes. Five of these genes have orthologs in the common chimpanzee, and three of them (KIRCI, KIR2DL4, and KIR2DL5) also have human orthologs. The remaining two genes are KIR3D paralogous to the human and common chimpanzee major histocompatibility complex A- and/or -B-specific KIRs. Within a pygmy chimpanzee family, KIR haplotypes were defined. Simple patterns on Southern blot were due to inheritance of "short" KIR haplotypes containing only three KIR genes, KIRCI, KIR2DL4, and KIR3D, each of which represents one of the three major KIR lineages. These three genes in pygmy chimpanzees or their corresponding genes in humans and common chimpanzees form the conserved "framework" common to all KIR haplotypes in these species and upon which haplotypic diversity is built. The fecundity and health of individual pygmy chimpanzees who are homozygotes for short KIR haplotypes attest to the viability of short KIR haplotypes, indicating that they can provide minimal, essential KIRs for the natural killer and T cells of the hominoid immune system.

'Test n Treat' (TnT): a cluster randomized feasibility trial of on-site rapid Chlamydia trachomatis tests and treatment in ethnically diverse, sexually active teenagers attending technical colleges.

OBJECTIVES: We conducted a cluster-randomized feasibility trial of 90-minute Chlamydia trachomatis tests and same day on-site treatment ('Test n Treat/TnT') in six technical colleges in London, England, to assess TnT uptake rates; follow-up rates; prevalence of C. trachomatis at baseline and 7 months; time to treatment; acceptability of TnT. METHODS: Participants completed questionnaires and provided genitourinary samples at baseline and 7 months. Participants were informed that baseline samples would not be tested for 7 months and were advised to get screened independently. Colleges were randomly allocated 1:1 to intervention (TnT) or control (no TnT). One month and 4 months post recruitment, participants at intervention colleges were texted invitations for on-site free C. trachomatis tests. A purposive sample of students who did/did not attend for screening were interviewed (n = 26). RESULTS: Five hundred and nine sexually active students were recruited: median age 17.9 years, 47% male, 50% black ethnicity, 55% reporting two or more sexual partners in the previous year. TnT uptake was 13% (33/259; 95% CI 8.9-17.4%) at 1 month and 10% (26/259; 6.7-14.4%) at 4 months with overall C. trachomatis positivity 5.1% (3/59; 1.1-14.2%). Follow-up at 7 months was 62% (317/509) for questionnaires and 52% (264/509) for samples. C. trachomatis prevalence was 6.2% (31/503) at baseline and 6.1% (16/264) at 7 months. Median time from test to treatment was 15 h. Interviews suggested low test uptake was associated with not feeling at risk, perceptions of stigma, and little knowledge of sexually transmitted infections (STIs). CONCLUSIONS: Despite high C. trachomatis rates at baseline and follow-up, uptake of testing was low. Like many countries, England urgently needs better sex education, including making STI testing routine/normal. Trial registration ISRCTN58038795.

Liverpool Ultrasound Pictorial Chart: the development of a new method of documenting anal sphincter injury diagnosed by endoanal ultrasound.

OBJECTIVE: To develop and validate a pictorial chart that documents ultrasound examination of the anal sphincter. DESIGN: A new pictorial chart (Liverpool Ultrasound Pictorial Chart [LUPIC]) depicting the normal anatomy of the anal sphincter was developed. METHODS: To validate LUPIC, two observers documented the findings of 296 endoanal scans. Reliability was assessed between observers using kappa agreement for presence and position of sphincter defects. To validate the use of LUPIC by different observers, a video of ten endoanal ultrasound scans was reviewed by our local expert (gold standard). Seven clinicians underwent test-retest analysis. Kappa agreement was calculated to assess intra-observer and gold standard versus observer agreement for the overall presence of sphincter defects and compared with the gold standard. Complete agreement for the position and level of sphincter defects was assessed for the five abnormal scans. MAIN OUTCOME MEASURES: Excellent agreement between the two observers was found for the presence (kappa 0.99), position and level of external anal sphincter defects documented using LUPIC. The intra-observer and gold standard versus observer kappa values of experienced clinicians (A-E) showed good agreement for the overall presence of sphincter defects. Complete agreement for the position and level of sphincter defects was found in 23 of 35 (66%) observations. CONCLUSIONS: LUPIC is designed and validated method of documenting anal sphincter injury diagnosed by endoanal ultrasound. Standardisation of endoanal ultrasound findings by using LUPIC may help correlate the degree of damage with patient symptoms.

Surgical management of pelvic organ prolapse in women.

BACKGROUND: Pelvic organ prolapse may occur in up to 50% of parous women. A variety of urinary, bowel and sexual symptoms may be associated with prolapse. OBJECTIVES: To determine the effects of the many different surgeries in the management of pelvic organ prolapse. SEARCH STRATEGY: We searched the Cochrane Incontinence Group Specialised Trials Register (searched 3 May 2006) and reference lists of relevant articles. We also contacted researchers in the field. SELECTION CRITERIA: Randomised or quasi-randomised controlled trials that included surgical operations for pelvic organ prolapse. DATA COLLECTION AND ANALYSIS: Trials were assessed and data extracted independently by two reviewers. Six investigators were contacted for additional information with five responding. MAIN RESULTS: Twenty two randomised controlled trials were identified evaluating 2368 women. Abdominal sacral colpopexy was better than vaginal sacrospinous colpopexy in terms of a lower rate of recurrent vault prolapse (RR 0.23, 95% CI 0.07 to 0.77) and less dyspareunia (RR 0.39, 95% CI 0.18 to 0.86), but the trend towards a lower re-operation rate for prolapse following abdominal sacrocolpopexy was not statistically significant (RR 0.46, 95% CI 0.19 to 1.11). However, the vaginal sacrospinous colpopexy was quicker and cheaper to perform and women had an earlier return to activities of daily living. The data were too few to evaluate other clinical outcomes and adverse events. The three trials contributing to this comparison were clinically heterogeneous. For the anterior vaginal wall prolapse, standard anterior repair was associated with more recurrent cystoceles than when supplemented by polyglactin mesh inlay (RR 1.39, 95% CI 1.02 to 1.90) or porcine dermis mesh inlay (RR 2.72, 95% CI 1.20 to 6.14), but data on morbidity, other clinical outcomes and for other mesh or graft materials were too few for reliable comparisons. For posterior vaginal wall prolapse, the vaginal approach was associated with a lower rate of recurrent rectocele and/or enterocele than the transanal approach (RR 0.24, 95% CI 0.09 to 0.64), although there was a higher blood loss and postoperative narcotic use. However, data on the effect of surgery on bowel symptoms and the use of polyglactin mesh inlay or porcine small intestine graft inlay on the risk of recurrent rectocele were insufficient for meta-analysis.Meta-analysis on the impact of pelvic organ prolapse surgery on continence issues was limited and inconclusive, although about 10% of women developed new urinary symptoms after surgery. Although the addition of tension-free vaginal tape to endopelvic fascia plication (RR 5.5, 95% CI 1.36 to 22.32) and Burch colposuspension to abdominal sacrocolpopexy (RR 2.13, 95% CI 1.39 to 3.24) were followed by a lower risk of women developing new postoperative stress incontinence, but other outcomes, particularly economic, remain to be evaluated. AUTHORS' CONCLUSIONS: Abdominal sacrocolpopexy is associated with a lower rate of recurrent vault prolapse and dyspareunia than the vaginal sacrospinous colpopexy. These benefits must be balanced against a longer operating time, longer time to return to activities of daily living and increased cost of the abdominal approach. The use of mesh or graft inlays at the time of anterior vaginal wall repair may reduce the risk of recurrent cystocele. Posterior vaginal wall repair may be better than transanal repair in the management of rectoceles in terms of recurrence of prolapse. The addition of a continence procedure to a prolapse repair operation may reduce the incidence of postoperative urinary incontinence but this benefit needs to be balanced against possible differences in costs and adverse effects. Adequately powered randomised controlled clinical trials are urgently needed.

MR1-restricted mucosal-associated invariant T (MAIT) cells respond to mycobacterial vaccination and infection in nonhuman primates.

Studies on mucosal-associated invariant T cells (MAITs) in nonhuman primates (NHP), a physiologically relevant model of human immunity, are handicapped due to a lack of macaque MAIT-specific reagents. Here we show that while MR1 ligand-contact residues are conserved between human and multiple NHP species, three T-cell receptor contact-residue mutations in NHP MR1 diminish binding of human MR1 tetramers to macaque MAITs. Construction of naturally loaded macaque MR1 tetramers facilitated identification and characterization of macaque MR1-binding ligands and MAITs, both of which mirrored their human counterparts. Using the macaque MR1 tetramer we show that NHP MAITs activated in vivo in response to both Bacillus Calmette-Guerin vaccination and Mycobacterium tuberculosis infection. These results demonstrate that NHP and human MR1 and MAITs function analogously, and establish a preclinical animal model to test MAIT-targeted vaccines and therapeutics for human infectious and autoimmune disease.

Re-engineering the target specificity of Clostridial neurotoxins - a route to novel therapeutics.

The ability to chemically couple proteins to LH(N)-fragments of clostridial neurotoxins and create novel molecules with selectivity for cells other than the natural target cell of the native neurotoxin is well established. Such molecules are able to inhibit exocytosis in the target cell and have the potential to be therapeutically beneficial where secretion from a particular cell plays a causative role in a disease or medical condition. To date, these molecules have been produced by chemical coupling of the LH(N)-fragment and the targeting ligand. This is, however, not a suitable basis for producing pharmaceutical agents as the products are ill defined, difficult to control and heterogeneous. Also, the molecules described to date have targeted neuroendocrine cells that are susceptible to native neurotoxins, and therefore the benefit of creating a molecule with a novel targeting domain has been limited. In this paper, the production of a fully recombinant fusion protein from a recombinant gene encoding both the LH(N)-domain of a clostridial neurotoxin and a specific targeting domain is described, together with the ability of such recombinant fusion proteins to inhibit secretion from non-neuronal target cells. Specifically, a novel protein consisting of the LH(N)-domains of botulinum neurotoxin type C and epidermal growth factor (EGF) that is able to inhibit secretion of mucus from epithelial cells is reported. Such a molecule has the potential to prevent mucus hypersecretion in asthma and chronic obstructive pulmonary disease.

An investigation of dose calculation accuracy in intensity-modulated radiotherapy of sites in the head & neck.

Knowledge of the accuracy of dose calculations in intensity-modulated radiotherapy of the head and neck is essential for clinical confidence in these highly conformal treatments. High dose gradients are frequently placed very close to critical structures, such as the spinal cord, and good coverage of complex shaped nodal target volumes is important for long term-local control. A phantom study is presented comparing the performance of standard clinical pencil-beam and collapsed-cone dose algorithms to Monte Carlo calculation and three-dimensional gel dosimetry measurement. Calculations and measurements are individually normalized to the median dose in the primary planning target volume, making this a purely relative study. The phantom simulates tissue, air and bone for a typical neck section and is treated using an inverse-planned 5-field IMRT treatment, similar in character to clinically used class solutions. Results indicate that the pencil-beam algorithm fails to correctly model the relative dose distribution surrounding the air cavity, leading to an cverestimate of the target coverage. The collapsed-cone and Monte Carlo results are very similar, indicating that the clinical collapsed-cone algorithm is perfectly sufficient for routine clinical use. The gel measurement shows generally good agreement with the collapsed-cone and Monte Carlo calculated dose, particularly in the spinal cord dose and nodal target coverage, thus giving greater confidence in the use of this class solution.

The financial and service implications of splitting fixed-dose antiretroviral drugs - a case study.

In 2010/2011, regional commissioners withdrew payment for the fixed-dose combination Combivir, forcing a switch to component drugs. This was deemed clinically acceptable and annual savings of £44 k expected. We estimated the true costs of switching and examined patient outcomes. Information for 46 patients using Combivir was extracted from case notes for each clinical contact in the 12 months pre- and post-switch (clinician seen, tests, antiretrovirals). Post-switch care costs £93/patient more annually versus pre-switch (95% CI £424 to £609), yielding £4278/year more post-switch for all patients. Drug and pathology costs were more expensive post-switch and extra clinical visits required. None of these results were statistically significant. Forty-two per cent of patients switched directly or in the subsequent year to an alternative fixed-dose combination rather than generics. Costs in this group were significantly higher post-switch driven by drug cost. Six patients (13%) reported problems with the switch including confusion around dosing and new side effects. As less-expensive generic antiretroviral drugs become available, it may appear cheaper to switch from fixed-dose combinations to component drugs. However, the additional clinical costs involved may outweigh the initial cost savings of the drugs and switching may cause confusion for some patients, risking loss of adherence.

Comparison of intensity-modulated tomotherapy with stereotactically guided conformal radiotherapy for brain tumors.

PURPOSE: Intensity-modulated radiotherapy (IMRT) offers the potential to more closely conform dose distributions to the target, and spare organs at risk (OAR). Its clinical value is still being defined. The present study aims to compare IMRT with stereotactically guided conformal radiotherapy (SCRT) for patients with medium size convex-shaped brain tumors. METHODS AND MATERIALS: Five patients planned with SCRT were replanned with the IMRT-tomotherapy method using the Peacock system (Nomos Corporation). The planning target volume (PTV) and relevant OAR were assessed, and compared relative to SCRT plans using dose statistics, dose-volume histograms (DVH), and the Radiation Therapy Oncology Group (RTOG) stereotactic radiosurgery criteria. RESULTS: The median and mean PTV were 78 cm3 and 85 cm3 respectively (range 62-119 cm3). The differences in PTV doses for the whole group (Peacock-SCRT +/-1 SD) were 2%+/-1.8 (minimum PTV), and 0.1%+/-1.9 (maximum PTV). The PTV homogeneity achieved by Peacock was 12.1%+/-1.7 compared to 13.9%+/-1.3 with SCRT. Using RTOG guidelines, Peacock plans provided acceptable PTV coverage for all 5/5 plans compared to minor coverage deviations in 4/5 SCRT plans; acceptable homogeneity index for both plans (Peacock = 1.1 vs. SCRT = 1.2); and comparable conformity index (1.4 each). As a consequence of the transaxial method of arc delivery, the optic nerves received mean and maximum doses that were 11.1 to 11.6%, and 10.3 to 15.2% higher respectively with Peacock plan. The maximum optic lens, and brainstem dose were 3.1 to 4.8% higher, and 0.6% lower respectively with Peacock plan. However, all doses remained below the tolerance threshold (5 Gy for lens, and 50 Gy for optic nerves) and were clinically acceptable. CONCLUSIONS: The Peacock method provided improved PTV coverage, albeit small, in this group of convex tumors. Although the OAR doses were higher using the Peacock plans, all doses remained within the clinically defined threshold and were clinically acceptable. Further improvements may be expected using other methods of IMRT planning that do not limit the treatment delivery to transaxial arcs. Each IMRT system needs to be individually assessed as the paradigm utilized may provide different outcomes.

A Comparison of clinical target volumes determined by CT and MRI for the radiotherapy planning of base of skull meningiomas.

PURPOSE: To assess the utility of image registration and to compare the localization of clinical target volumes (CTV) using CT and MRI for patients with base of skull meningiomas undergoing radiotherapy. METHODS AND MATERIALS: Seven patients were imaged using CT and a T1-weighted MR volumetric sequence. Following image registration using a chamfer-matching algorithm, transaxial MR slices were reconstructed to match the planning CT slices. The accuracy of the image fusion was assessed in a preliminary study with matching accuracy better than 1.5 mm. The CTV in each patient was separately segmented by two independent observers for both CT and reconstructed MR image sets. Scalar and vector assessments were made of the difference in radial extent between the two outlines on each transaxial plane for all patients. A positive vector value corresponded to a greater extension of the tumor on MR compared to CT and vice versa. Scalar measurements compared the modulus of the differences between MR and CT, regardless of which volume was more extensive. Qualitative comparisons were also performed. RESULTS: Interobserver difference was small with a mean (+/- 1SD) volume difference of 1.5 +/- 1.5 cm(3) for CT and 0.5 +/- 1.0 cm(3) for MRI. The mean CT- and MR- CTVs were 17.6 +/-10.8 and 19.6 +/-14.2 cm(3) respectively. The mean overlap and composite volumes were 13.8 +/-10. 1 and 23.3 +/-14.8 cm(3) respectively. Average scalar differences in the left, right, anterior, and posterior directions were 6.0 +/- 7.0, 3.3 +/- 2.5, 4.9 +/- 3.9, and 4.5 +/- 5.0 mm respectively. The average vector differences were 3.3 +/- 8.5, -0.3 +/- 3.8, 1.1 +/- 5. 8, 1.5 +/- 6.4 mm (for left, right, anterior, and posterior directions respectively). Qualitatively, MR appeared to discern more tumor involvement in soft tissue regions adjacent to the skull base whereas CT appeared to provide larger target volumes within bony regions. CONCLUSIONS: MRI appeared to define CTVs that were larger but not inclusive of CT-defined CTVs. Although the average vector differences were small, the differences on individual borders could be large. In some instances, the CT or MR volumes were vastly different, each providing separate information. Therefore, the use of MRI and CT is complementary. Until accurate histological confirmation of disease extent is available, it is prudent to consider composite CT/MR volumes for the radiotherapy planning of base of skull meningiomas.

Optimization of stereotactically-guided conformal treatment planning of sellar and parasellar tumors, based on normal brain dose volume histograms.

PURPOSE: To investigate the optimal treatment plan for stereotactically-guided conformal radiotherapy (SCRT) of sellar and parasellar lesions, with respect to sparing normal brain tissue, in the context of routine treatment delivery, based on dose volume histogram analysis. METHODS AND MATERIALS: Computed tomography (CT) data sets for 8 patients with sellar- and parasellar-based tumors (6 pituitary adenomas and 2 meningiomas) have been used in this study. Treatment plans were prepared for 3-coplanar and 3-, 4-, 6-, and 30-noncoplanar-field arrangements to obtain 95% isodose coverage of the planning target volume (PTV) for each plan. Conformal shaping was achieved by customized blocks generated with the beams eye view (BEV) facility. Dose volume histograms (DVH) were calculated for the normal brain (excluding the PTV), and comparisons made for normal tissue sparing for all treatment plans at > or =80%, > or =60%, and > or =40% of the prescribed dose. RESULTS: The mean volume of normal brain receiving > or =80% and > or =60% of the prescribed dose decreased by 22.3% (range 14.8-35.1%, standard deviation sigma = 7.5%) and 47.6% (range 25.8-69.1%, sigma = 13.2%), respectively, with a 4-field noncoplanar technique when compared with a conventional 3-field coplanar technique. Adding 2 further fields, from 4-noncoplanar to 6-noncoplanar fields reduced the mean normal brain volume receiving > or =80% of the prescribed dose by a further 4.1% (range -6.5-11.8%, sigma = 6.4%), and the volume receiving > or =60% by 3.3% (range -5.5-12.2%, sigma = 5.4%), neither of which were statistically significant. Each case must be considered individually however, as a wide range is seen in the volume spared when increasing the number of fields from 4 to 6. Comparing the 4- and 6-field noncoplanar techniques to a 30-field conformal field approach (simulating a dynamic arc plan) revealed near-equivalent normal tissue sparing. CONCLUSION: Four to six widely spaced, fixed-conformal fields provide the optimum class solution for the treatment of sellar and parasellar lesions, both in terms of normal brain tissue sparing and providing a relatively straightforward patient setup. Increasing the number of fields did not result in further significant sparing, with no clear benefit from techniques approaching dynamic conformal radiotherapy in the cases examined.

Potential role of intensity-modulated radiotherapy in the treatment of tumors of the maxillary sinus.

PURPOSE: To assess 3-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) techniques to see whether doses to critical structures could be reduced while maintaining planning target volume (PTV) coverage in patients receiving conventional radiotherapy (RT) for carcinoma of the maxillary sinus because of the risk of radiation-induced complications, particularly visual loss. METHODS AND MATERIALS: Six patients who had recently received conventional RT for carcinoma of the maxillary sinus were studied. Conventional RT, 3D-CRT, and step-and-shoot IMRT plans were prepared using the same 2-field arrangement. The effect of reducing the number of segments in the IMRT beams was investigated. RESULTS: 3D-CRT and IMRT reduced the brain and ipsilateral parotid gland doses compared with the conventional plans. IMRT reduced doses to both optic nerves; for the contralateral optic nerve, 15-segment IMRT plans delivered an average maximal dose of 56.4 Gy (range 53.9-59.3) compared with 65.7 Gy (range 65.3-65.9) and 64.2 Gy (range 61.4-65.6) for conventional RT and 3D-CRT, respectively. IMRT also gave improved PTV homogeneity and improved coverage, with an average of 8.5% (range 7.0-11.7%) of the volume receiving <95% of the prescription dose (64 Gy) compared with 14.7% (range 14.1-15.9%) and 15.1% (range 14.4-16.1%) with conventional RT and 3D-CRT, respectively. Little difference was found between the 15 and 7-segment plans, but 5 segments resulted in a reduced minimal PTV dose. CONCLUSIONS: IMRT offers significant advantages over conventional RT and 3D-CRT techniques for treatment of maxillary sinus tumors. Good results can be obtained from 7 segments per beam without compromising the PTV coverage. This number of segments is practical for implementation in a busy RT department.

Synthesis and pharmacological characterization of a series of leukotriene analogues with antagonist and agonist activities.

The synthesis and biological characterization of a series of novel leukotriene antagonists and agonists are reported. All of these compounds are derivatives of (5S,6R,7Z)-5-hydroxy-6-mercapto-9-phenyl-7-nonenoic acid. One of the more potent compounds is (5S,6R,7Z)-6-[[(4-carboxy-2-methoxyphenyl)methyl]thio]-5-hydroxy-9 -(4- heptylphenyl)-7-nonenoic acid (3f). In vitro evaluation of this compound on guinea pig trachea revealed that it is a competitive antagonist of LTD4 and LTE4 with pKB values of 6.4 and 5.8, respectively. On guinea pig ileum, the pKB values obtained for it with LTD4 and E4 were both 7.2. The selectivity of 3f was shown by its lack of effect on carbachol, histamine, and barium chloride concentration-response curves in guinea pig trachea.

Chemically stable homocinnamyl analogues of the leukotrienes: synthesis and preliminary biological evaluation.

The synthesis and biological characterization of a series of stable leukotriene analogues (2) are reported. They are derivatives of (5S,6R,7Z)-6-peptidyl-5-hydroxy-9-phenyl-7-nonenoic acid, in which the phenyl group is variously substituted with a heptanyl, 2-heptenyl, or hexanyloxy chain (R1) and the peptide is either glutathionyl, cysteinylglycinyl, or cysteinyl. The most potent agonist is (5S,6R,7Z)-6-S-glutathionyl-5-hydroxy-9-(4-heptanylphenyl)-7 -nonenoic acid. This analogue has an EC50 value of 74.5 nM, in the presence of 1-serine borate (45 mM), on guinea pig tracheal spirals. The agonist activity of the cysteinylglycinyl- and the cysteinyl-substituted analogues was inhibited by FPL-55712. Three of the analogues were weak leukotriene antagonists in vitro on guinea pig tracheal spirals. The most potent of these was (5S,6R,7Z)-6-S-cysteinyl-5-hydroxy-9-(2-heptanylphenyl)-7-++ +nonenoic acid. At 10 microM, this analogue inhibited by 28% the contraction induced by 8 nM LTE4.

A novel series of selective leukotriene antagonists: exploration and optimization of the acidic region in 1,6-disubstituted indoles and indazoles.

A systematic structure-activity exploration of the carboxylic acid region in a series of indole- or indazole-derived leukotriene antagonists 1 led to several discoveries. Use of the 3-methoxy-p-tolyl fragment (illustrated in acid 1) for connecting the indole and the acidic site provides the most potent carboxylic acids 1, tetrazoles 20, and aryl sulfonimides 21. The aryl sulfonimides are 5-500 times more potent (in vitro and/or in vivo) than the corresponding carboxylic acids 1. The o-tolyl sulfonimides such as 114 show greater oral potency than the phenyl sulfonimides at a given level of in vitro activity. Acidic keto sulfone derivatives 10 (Nu = CH-(CO2CH3)SO2Ph) mimic the activity of the sulfonimides.

Changes to dose in the build-up region when using multi-leaf collimators in place of lead blocks supported on an accessory tray.

Doses in the build-up region have been compared for regular fields with and without a perspex accessory tray and for two irregular fields defined by either a Philips multi-leaf collimator (MLC) or lead blocks. The results show an increase in doses within the build-up region, by up to a factor of two, primarily due to the presence of the accessory tray. Fields shaped with the MLC exhibited build-up characteristics similar to those in unblocked fields and hence there will be systematic changes to the build-up dose when treatments are transferred from lead blocking techniques to those using an MLC mounted within the treatment head.