Evidence of discrete yellowfin tuna (Thunnus albacares) populations demands rethink of management for this globally important resource.

Tropical tuna fisheries are central to food security and economic development of many regions of the world. Contemporary population assessment and management generally assume these fisheries exploit a single mixed spawning population, within ocean basins. To date population genetics has lacked the required power to conclusively test this assumption. Here we demonstrate heterogeneous population structure among yellowfin tuna sampled at three locations across the Pacific Ocean (western, central, and eastern) via analysis of double digest restriction-site associated DNA using Next Generation Sequencing technology. The differences among locations are such that individuals sampled from one of the three regions examined can be assigned with close to 100% accuracy demonstrating the power of this approach for providing practical markers for fishery independent verification of catch provenance in a way not achieved by previous techniques. Given these results, an extended pan-tropical survey of yellowfin tuna using this approach will not only help combat the largest threat to sustainable fisheries (i.e. illegal, unreported, and unregulated fishing) but will also provide a basis to transform current monitoring, assessment, and management approaches for this globally significant species.

The effects of weight and chemosensitivity on respiratory sleep abnormalities: a family study.

The relationship between low-awake chemosensitivity, exogenous respiratory load (obesity) and respiratory/oxygenation patterns during sleep was evaluated in a family with overall low ventilatory responses to hypoxia and hypercapnia. Six family members were of normal weight, in good health and had normal pulmonary function tests. Only one of these subjects had totally normal responses to the chemical control of breathing. A seventh family member had loaded breathing because of severe obesity. His ventilatory and mouth occlusion pressure responses to hypoxia or hypercapnia were severely blunted. After weight loss (200 percent of ideal body weight to 133 percent) the ventilatory responses were improved but still abnormally low. Significant nocturnal respiratory abnormalities and oxygen desaturation were only seen in the overweight member and improved following weight loss (load reduction).

Pulmonary effects in man of oral prizidilol hydrochloride (SK&F 92657), a new antihypertensive agent.

The effects on heart rate, blood pressure and pulmonary function of single oral doses of prizidilol hydrochloride (400 mg SK&F 92657) and propranolol (40 mg) were compared with placebo in nine healthy volunteers, in a double blind crossover study. Prizidilol had no effect on heart rate while propranolol caused a significant reduction compared with placebo. Diastolic blood pressure was lowered to the same extent by both prizidilol and propranolol. Propranolol significantly reduced the forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC) and the maximal expiratory flow at 50% vital capacity (MEF 50). Prizidilol had no effect on flow-volume loop parameters. Effective pulmonary blood flow was not altered by propranolol, but it was significantly increased by prizidilol. Oral prizidilol exerts its hypotensive effect by vasodilatation without reflex tachycardia. It does not cause airways obstruction in healthy subjects.

Respiratory improvement by muscle training in adult-onset acid maltase deficiency.

A patient with progressive involvement of respiratory function from adult-onset acid maltase deficiency is reported. The decrement in objective and subjective waking and sleeping respiratory variables was significantly reversed by inspiratory muscle training. This training was accomplished simply by breathing against inspiratory resistors for 15 minutes twice a day. Inspiratory muscle training may prove valuable in other patients with progressive neuromuscular disorders that involve respiratory muscle function.

A multicentre comparison of clindamycin and metronidazole in the treatment of anaerobic infections.

One hundred and seventy patients with intra-abdominal infection with non-sporing anaerobes were prospectively studied in an international multicentre study. Patients were randomly allocated to treatment with clindamycin or metronidazole, for a minimum of 48 h to a maximum of 7 days. Other antimicrobial therapy was permitted if indicated by in vitro susceptibility testing. The commonest infections were peritonitis, intra-abdominal abscesses and appendicitis (72 cases), colorectal carcinoma (23 cases), intestinal perforation (16 cases) and diverticulitis (13 cases). Thirty patients received no other antimicrobial chemotherapy and in a further 94 patients, an aminoglycoside was given in addition to the study drugs. In 38 patients the infection required no surgical intervention. Appendicectomy was commonly performed and surgical drainage of pus was required in 14 patients. These variables were evenly distributed between the treatment groups. Both clindamycin and metronidazole were found to be effective therapy for anaerobic infections and were well tolerated. Of the 9 deaths in the study, 7 were in the clindamycin group, and 2 in the metronidazole group. The study protocol allowed patients who were responding poorly to treatment to be crossed over to the alternative therapy. This procedure was followed in 6 patients, 5 of whom were originally receiving clindamycin. It is concluded that metronidazole is as effective for anaerobic infections as clindamycin.

Radionuclide venography in the management of proximal venous occlusion. A comparison with X-ray contrast venography.

Ascending contrast venography often fails to show the proximal venous system when there is co-existing occlusion of femoral or iliac veins. Retrograde and pertrochanteric venography both have severe limitations in terms of invasiveness and reliability. Radionuclide venography (RNV) is suggested as a less invasive alternative. 100 patients were investigated by both RNV and X-ray contrast venography (XRV). There was a 72% overall correlation between two methods of investigation. The proximal definition of XRV was limited in those cases with femoral obstruction. RNV, however gave progressively better views as imaging became more proximal and this was accentuated in the presence of femoral or iliac occlusion. RNV is simple and easy to perform and less invasive than XRV. The definition at calf level is such that it cannot at this stage replace XRV as the standard diagnostic procedure. However, in patients with proximal occlusions it gives more reliable information than that obtainable by ascending contrast venography.

Depression of lecithin-cholesterol acyltransferase esterification in vitamin E-deficient monkeys.

Vitamin E deficiency in two species of monkeys (capuchins and cynamolgus) reduced the in vitro cholesterol esterification by plasma lecithin-cholesterol acyltransferase. The reduction was greates in the most deficient species and in animals fed a diet rich in polyunsaturated fat (safflower oil) stripped of vitamin E. The best correlate of total esterification was the plasma concentration of free cholesterol which reflected the degree of hyperlipidemia, found to be greatest in capuchins fed coconut oil. A logical explanation for the decreased LCAT activity in vitamin E deficiency would be peroxidative damage of substrate (the PUFA of lecithin) or of sulfhydryl sited on lecithin-cholesterol acyltransferase itself. However, neither case was fully supported by the data suggesting that additional information concerning the nature of the reaction and the role of vitamin E is required.