A new blue whale song-type described for the Arabian Sea and Western Indian Ocean

Blue whales Balaenoptera musculus in the Indian Ocean (IO) are currently thought to represent 2 or 3 subspecies (B. m. intermedia, B. m. brevicauda, B. m. indica), and believed to be structured into 4 populations, each with a diagnostic song-type. Here we describe a previously unreported song-type that implies the probable existence of a population that has been undetected or conflated with another population. The novel song-type was recorded off Oman in the northern IO/Arabian Sea, off the western Chagos Archipelago in the equatorial central IO, and off Madagascar in the southwestern IO. As this is the only blue whale song that has been identified in the western Arabian Sea, we label it the ‘Northwest Indian Ocean’ song-type to distinguish it from other regional song-types. Spatiotemporal variation suggested a distribution west of 70°E, with potential affinity for the northern IO/Arabian Sea, and only minor presence in the southwestern IO. Timing of presence off Oman suggested that intensive illegal Soviet whaling that took 1294 blue whales in the 1960s likely targeted this population, as opposed to the more widely distributed ‘Sri Lanka’ acoustic population as previously assumed. Based upon geographic distribution and potential aseasonal reproduction found in the Soviet catch data, we suggest that if there is a northern IO subspecies (B. m. indica), it is likely this population. Moreover, the potentially restricted range, intensive historic whaling, and the fact that the song-type has been previously undetected, suggests a small population that is in critical need of status assessment and conservation action.

One-year swallowing outcomes following transoral laser microsurgery +/- adjuvant therapy versus primary chemoradiotherapy for advanced stage oropharyngeal squamous cell carcinoma

OBJECTIVES

To assess the between-group change in swallowing function from baseline to 12 months following treatment, for patients treated for resectable stage III and IVA oropharyngeal squamous cell carcinoma. To assess the within-group change in swallowing function between 3 and 12 months following treatment.

DESIGN

Non-randomised cohort study.

SETTING

A single head and neck cancer unit with oncology services held at the nearby regional treatment centre.

PARTICIPANTS

Twenty-five patients treated with Transoral Laser Microsurgery +/- adjuvant (chemo)radiotherapy (Transoral Laser Microsurgery) observed alongside an historic cohort of 33 patients treated with (chemo)radiotherapy.

MAIN OUTCOME MEASURES

The patient reported MD Anderson Dysphagia Inventory (MDADI), an objective timed Water Swallow Test, and the clinician rated normalcy of diet subsection of the Performance of Swallowing Scale .

RESULTS

Between baseline and 12 months, patients treated with primary (chemo)radiotherapy demonstrated greater deterioration in swallowing function compared to Transoral Laser Microsurgery for all 3 swallowing measures. Between 3 and 12 months, the only significant change was an improvement in Performance of Swallowing Scale scores in the (chemo)radiotherapy group.

CONCLUSIONS

This is the first study to report the results of a complimentary set of swallowing measures for patients treated with Transoral Laser Microsurgery, observed alongside a cohort of (chemo)radiotherapy patients. The preliminary results suggest a benefit in swallowing function for Transoral Laser Microsurgery over (chemo)radiotherapy during the year following treatment.

Radon in homes and risk of lung cancer: collaborative analysis of individual data from 13 European case-control studies

OBJECTIVE

To determine the risk of lung cancer associated with exposure at home to the radioactive disintegration products of naturally occurring radon gas.

DESIGN

Collaborative analysis of individual data from 13 case-control studies of residential radon and lung cancer.

SETTING

Nine European countries.

SUBJECTS

7148 cases of lung cancer and 14,208 controls.

MAIN OUTCOME MEASURES

Relative risks of lung cancer and radon gas concentrations in homes inhabited during the previous 5-34 years measured in becquerels (radon disintegrations per second) per cubic metre (Bq/m3) of household air.

RESULTS

The mean measured radon concentration in homes of people in the control group was 97 Bq/m3, with 11% measuring > 200 and 4% measuring > 400 Bq/m3. For cases of lung cancer the mean concentration was 104 Bq/m3. The risk of lung cancer increased by 8.4% (95% confidence interval 3.0% to 15.8%) per 100 Bq/m3 increase in measured radon (P = 0.0007). This corresponds to an increase of 16% (5% to 31%) per 100 Bq/m3 increase in usual radon--that is, after correction for the dilution caused by random uncertainties in measuring radon concentrations. The dose-response relation seemed to be linear with no threshold and remained significant (P = 0.04) in analyses limited to individuals from homes with measured radon < 200 Bq/m3. The proportionate excess risk did not differ significantly with study, age, sex, or smoking. In the absence of other causes of death, the absolute risks of lung cancer by age 75 years at usual radon concentrations of 0, 100, and 400 Bq/m3 would be about 0.4%, 0.5%, and 0.7%, respectively, for lifelong non-smokers, and about 25 times greater (10%, 12%, and 16%) for cigarette smokers.

CONCLUSIONS

Collectively, though not separately, these studies show appreciable hazards from residential radon, particularly for smokers and recent ex-smokers, and indicate that it is responsible for about 2% of all deaths from cancer in Europe.

Spatial variation of natural radiation and childhood leukaemia incidence in Great Britain

This paper describes an analysis of the geographical variation of childhood leukaemia incidence in Great Britain over a 15 year period in relation to natural radiation (gamma and radon). Data at the level of the 459 district level local authorities in England, Wales and regional districts in Scotland are analysed in two complementary ways: first, by Poisson regressions with the inclusion of environmental covariates and a smooth spatial structure; secondly, by a hierarchical Bayesian model in which extra-Poisson variability is modelled explicitly in terms of spatial and non-spatial components. From this analysis, we deduce a strong indication that a main part of the variability is accounted for by a local neighbourhood 'clustering' structure. This structure is furthermore relatively stable over the 15 year period for the lymphocytic leukaemias which make up the majority of observed cases. We found no evidence of a positive association of childhood leukaemia incidence with outdoor or indoor gamma radiation levels. There is no consistent evidence of any association with radon levels. Indeed, in the Poisson regressions, a significant positive association was only observed for one 5-year period, a result which is not compatible with a stable environmental effect. Moreover, this positive association became clearly non-significant when over-dispersion relative to the Poisson distribution was taken into account.

Cetamolol: cardiovascular effects of a new cardioselective beta-adrenoceptor blocker possessing partial agonistic activity and lacking membrane-stabilizing activity

The cardiovascular effects of cetamolol, a new beta-adrenoceptor blocker, were studied in the anesthetized dog and cat and in the conscious dog and monkey. The compound was compared with other beta-blockers known to possess various degrees of cardioselectivity, partial agonistic effects, and membrane-stabilizing activity. In the anesthetized open-chest dog, cetamolol and pindolol produced similar cardiovascular effects in that the partial agonistic activity predominated over the blockade of beta-adrenoceptors. The partial agonistic activity of pindolol was greater than that of cetamolol. Unlike pindolol, cetamolol had no significant vasodilating property. However, the beta-blocking effects of these two drugs predominated in the anesthetized closed-chest dog, conscious dog and monkey. Atenolol, nadolol, and propranolol, which lack partial agonistic activity, produced cardiovascular changes characteristic of this type of beta-blocker in the animal preparation in which they were tested. In the anesthetized cat, comparison of the mean effective doses for the heart rate and blood pressure responses induced by isoproterenol showed that cetamolol was more cardioselective than metoprolol but less than acebutolol and atenolol. Evidence of the cardioselectivity of cetamolol was also obtained in the anesthetized closed-chest dog, although the degree of cardioselectivity of both cetamolol and atenolol was less marked than in the cat. When given orally to the conscious dog and monkey, cetamolol appeared to be well absorbed. The peak effect was observed after 1-2 h and persisted for the 5-h test period. It is concluded that cetamolol is a potent beta-blocker with a moderate degree of partial agonistic activity and cardioselectivity in in vivo experiments.