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The following article has been produced by the pharmacovigilance unit at the Veterinary Medicines Directorate (VMD) to provide a summary of some of the results from its surveillance work carried out in 2015Decrease in number of reports for food-producing speciesIncrease in number of pet animal reportsReports of dogs affected by medicines intended for large animals.

The following article has been produced by the pharmacovigilance unit at the Veterinary Medicines Directorate (VMD) to provide a summary of some of the results from its surveillance work carried out in 2014.

Fifty-five patients of mean age 69 (range 41–96) years with rectal cancer (Dukes' A: B: C, 11:24:20) underwent anterior resection using a double stapling technique under the care of one consultant surgeon between 1983 and 1988. The mean distance of the anastomosis from the anal margin was 7.2 (range 4–13) em. The clinical leak rate was 9 per cent (five patients). There were three postoperative deaths from pulmonary embolism, lower limb ischaemia and renal failure. On prospective follow-up, 35 patients had no evidence of local or systemic cancer a median of 32 (range 24–84) months after operation; seven have died from unrelated diseases and ten from metastatic cancer. Pelvic recurrence, in four patients at 9, 11, 12 and 50 months, has occurred only in association with widespread metastasis. These results suggest that the theoretical risks of an increase in the local recurrence rate rectal cancer after resection using a double stapling technique are not substantiated.

In a randomized controlled study of 411 patients undergoing elective colorectal surgery, the efficacy and safety of two different regimens of imipenem were compared with those of a control regimen of cefuroxime plus metronidazole. Surgical infections occurred in 92 (26·4 per cent) of 349 evaluable patients. There were no major differences between the three treatment groups. It is concluded that imipenem is as effective as cefuroxime plus metronidazole in the prevention of sepsis after elective colorectal procedures.

The paper describes a methodological approach to the investigation of maternal-fetal transfer of lead in a non-human primate species, with particular focus on skeletal tissue, which is known to be a site of lead deposition. Eight female cynomolgus monkeys were dosed with lead acetate during gestation, and in four of the animals, the isotopic composition of the lead was modified by enriching the amount of the stable isotope 204Pb included in the dose. Biopsy and dissection procedures for the preparation of bone samples for lead analysis and stable lead isotope analysis are described. Emphasis is placed on the containment of potential contamination of the samples by lead during preparation. Containment procedures included: use of a Class 100 clean room, special cleaning regimes and use of Teflon containers and stainless steel instruments. Preliminary data of lead concentrations in adult bone (trabecular and cortical) and fetal bone subsequent to the dosing regimen of lead during pregnancy, suggest notable differences between the two bone "compartments" examined. The bone samples of fetuses from the dams which had received enriched 204Pb showed drastically reduced 206Pb/204Pb isotope ratios.

Twenty-seven lead-isotope analyses for galena specimens from 14 localities in the Cobalt district represent sulphide-rich interflow sedimentary units in the Archean volcanic sequence, mineralized zones, fracture fillings, and local sulphide concentrations in the Cobalt Group (Proterozoic) sedimentary rocks, and vein-filling and breccia-cementing sulphides from within and near silver–arsenide veins. The analyses define a very homogeneous composition, averaging 206Pb/204Pb = 14.732, 2O7Pb/204Pb = 15.114, and 208Pb/204Pb = 34.301, for lead from these different geological settings. This result is in agreement with textural observations indicating a late paragenetic position for galena in the different settings mentioned. The model age for this lead is in general accord with the U–Pb age obtained in a study by Andrews et al. for a Nipissing diabase sheet at Gowganda.About one third of the galena specimens are interpreted by a two-stage evolution model to have formed or been remobilized during an event in the time range 1650–1945 Ma. The timing and character of this event are not clearly defined. The radiogenic composition of a specimen from the Pan Silver property is comparable to radiogenic values reported by Thorpe and suggests a young galena-forming event in the area.The lead-isotope data are permissive evidence for a genetic link between the Nipissing diabase sheets and mineralization of a variety of types in the Cobalt district. The metal source is not clearly indicated, but one analysis for Archean interflow sulphides suggests than an Archean source is unlikely for the lead in the silver–arsenide veins and other mineralized zones.

A redetermination of the age of the Otto stock by the whole-rock Rb–Sr isochron method indicates an age of 2160 ± 80 m.y., a figure that is substantially greater, by about 450 m.y., than the previously quoted value. This age, which is almost identical to the generally accepted value for the Nipissing diabase, appears to be consistent with both geological and palaeomagnetic observations.

The undeformed Newport megacrystic granite of northwestern Bonavista Bay postdates nearly all the other granites in the area, many of which are strongly cataclastic. It also cuts a regional swarm of diabase dikes. The Rb–Sr isochron of 332 ± 42 Ma for the Newport overlaps the 300 ± 18 Ma isochron age of the deformed Lockers Bay megacrystic granite which is cut both by the Newport and the diabase dikes. This indicates that the emplacement of the Lockers Bay pluton, its deformation, and the intrusion of the diabase dikes and the Newport granite all took place in the interval 290–320 Ma, that is in late Carboniferous times. Major movements along the Dover Fault line, which truncates the Newport in the southeast, probably occurred subsequent to this interval.

This paper presents some geophysical evidence bearing upon the nature of the Zuni Lineament in central New Mexico. Reported are some new lead isotope measurements, the results of a geomagnetic depth-sounding survey and the integration of these with the seismic data of Sandford. It is suggested that the Zuni Lineament may have been a major Precambrian feature of this area, but that it presently constitutes only a shallow zone of weakness. The zone does not appear to extend below a 20 km depth. Isotopically, the southeastern extension of the zone is not nearly so clear-cut as it is in the Rio Grande graben.

Three magnetic sector mass spectrometers have been interfaced with an Interdata Model4computer, which services them on a time sharing basis. Each mass spectrometer is equipped with a digital display at its console. This can be updated by the computer as required by the program instructions, with data selected by the setting of a console selector switch. The system can be operated in various modes. In the simplest mode, the ion current amplitudes are read into the computer at regular intervals, and are returned to the console display after digital filtering. Another mode provides for the storage of filtered data on digital magnetic tape, together with necessary information about scan rate and direction, and amplifier sensitivity. The tape represents a full description of the analysis, which can be processed later on the same or a larger computer. The third mode, as yet only tested for strontium isotope analysis, provides for real time processing of the spectrum. The computed isotope ratios are displayed at the console as the spectrum is scanned, so that the operator can observe the convergence of their averages. If he wishes, he can also observe the present estimates of the standard deviations of the average ratios. The three mass spectrometers may be operated simultaneously in different modes. In addition to data handling functions, the computer may be programmed to control the operating conditions during the analysis. To date, only the scan rate has been controlled in this way. The present paper presents a general description of the system and of its operation.

A method has been devised for the digital recording of mass spectra and for the completely automatic reduction of the data by means of an IBM 7040 digital computer. Spectral analysis of the base-line noise served as the basis of a decision to sample at half-second intervals. For a scanning rate of 20 seconds per unit mass separation, which is used for our lead trimethyl measurements, it is found possible and advantageous to filter the data digitally, using a filter with a half-power point at 0.15 cycles per second which is phase distortionless. The resulting record has a very much higher signal-to-noise ratio than is available directly from the mass spectrometer.After filtering the data, the computer proceeds to note the locations and amplitudes of maxima and minima in the spectra. It identifies the peaks and selects those that are required for computation. Tails due to pressure scattering are computed and corrections for such tails are applied to all peak heights. Decisions are made for each peak to determine whether maximum peak height or the height at the center of the area should be used, since it is advantageous to use different criteria for different peaks in the spectrum. From these data the spectrum is deconvolved and the isotope ratios for the lead samples are computed.While the procedures adopted are of general interest and are not restricted to any particular measuring system, details are given of the system applied in our laboratory and of the tape format used.