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1.
N Z Vet J ; 57(4): 208-14, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19649014

ABSTRACT

AIM: To assess a novel method for automatic in-line detection of clinical mastitis. METHODS: For a brief period at the start of milking for each cow, electrical conductivity of foremilk was measured for each quarter in turn, using a single sensor installed in the long milk tube (LMT) about 1.5 m downstream from the milking-machine claw. Sequential separation of flow between udder quarters was achieved by control of pulsation to individual teat cups within a conventional cluster. The ratio of conductivity values between quarters was used as an indicator of mastitis status. The concept was evaluated initially in a pilot trial in a 200-cow herd milked in a 23-stall swing-over herringbone milking parlour. It was then tested rigorously in a field trial in a 640-cow herd milked in a 50-stall rotary milking parlour. Both trials were conducted in the Waikato region of New Zealand. In the latter trial, sensor results were compared with visual inspection of a commercial in-line mastitis filter fitted to each milking unit. These filters were inspected for clots immediately after every cow's milking, for 3 weeks. The dataset of approximately 27,000 individual milkings was tested against several published or potential alternative 'gold standards' for diagnosing clinical mastitis. RESULTS: In the pilot trial, 12-14 clinical events were detected out of 19 true clinical quarters, with a false-alert rate of between three and five false electrical-conductivity alerts per 1,000 individual milkings. In the more rigorous field trial, sensitivity ranged from 68 to 88%, and the false-alert rate (false-alert episodes per 1,000 individual milkings) ranged from 2.3 to 7.0. CONCLUSION: The novel clinical mastitis detection system, based on separation of the flow and measurement of electrical conductivity from foremilk of individual udder quarters, has the potential to provide a new tool for helping farmers to monitor clinical mastitis in herds milked with conventional clusters.


Subject(s)
Dairying/instrumentation , Electric Conductivity , Mastitis, Bovine/diagnosis , Milk/chemistry , Animal Husbandry/instrumentation , Animal Husbandry/methods , Animals , Automation/instrumentation , Cattle , Dairying/methods , Female , New Zealand , Pilot Projects , Sensitivity and Specificity
2.
Neurosurgery ; 41(3): 669-72, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9310986

ABSTRACT

OBJECTIVE AND IMPORTANCE: A persistent hypoglossal artery, one of the embryonic carotid-basilar anastomoses that can fail to regress in the embryo and can be observed past birth, is one of the only congenital anatomic variations of the internal carotid artery (ICA) that can complicate the performance of carotid endarterectomy. When associated with atherosclerotic carotid artery disease, the recognition and intraoperative management of a persistent hypoglossal artery is important. CLINICAL PRESENTATION: A 72-year-old man presented with a symptom of transient right hemisphere ischemia, and although ultrasonography indicated a right ICA stenosis (and no other abnormality), angiography also demonstrated that the atherosclerotic plaque extended into the origin of a large right persistent hypoglossal artery arising 1.5 cm from the origin of the ICA. In this patient, the persistent hypoglossal artery was the only arterial supply to the basilar artery. INTERVENTION: The patient underwent a right ICA endarterectomy, and intraoperative angiography was necessary to ensure that the persistent hypoglossal artery was the vessel shunted during the arterial repair. CONCLUSION: Recognition of the primitive carotid-basilar anastomoses is important to surgeons who perform carotid endarterectomy and is not possible with ultrasonography alone. Intraoperative angiography enables the surgeon to accurately catheterize a persistent hypoglossal artery with a carotid shunt.


Subject(s)
Carotid Stenosis/surgery , Endarterectomy, Carotid/methods , Intracranial Arteriovenous Malformations/surgery , Basilar Artery/abnormalities , Basilar Artery/diagnostic imaging , Basilar Artery/surgery , Carotid Artery, Common/abnormalities , Carotid Artery, Common/diagnostic imaging , Carotid Artery, Common/surgery , Carotid Stenosis/diagnostic imaging , Cerebral Angiography , Humans , Intracranial Arteriovenous Malformations/diagnostic imaging , Male , Middle Aged
3.
J Dairy Sci ; 77(2): 426-32, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8182166

ABSTRACT

The timing and relation of changes in mammary epithelial cell tight junction integrity and mammary blood flow during a 36-h milking interval were studied in six lactating Saanen goats. An increase in lactose concentration in plasma, a decrease in transepithelial potential difference, and changes in ionic milk composition were used to indicate tight junction patency. After 36 h of milk accumulation, mammary tight junctions had become disrupted. Further analyses indicated that this disruption began after 21 h of milk accumulation and that mammary blood flow also started to decline after 21 h. The time when both events occurred was not significantly different from the time when milk secretion began to decline (19 h). Moreover, positive but nonsignificant correlations existed between these events. Mammary tight junctions became disrupted when milk secretion declined, suggesting that impairment of mammary tight junction integrity is associated with decreased milk secretion during an extended milking interval. The decline in mammary blood flow may be the result of a negative feedback response to a reduced demand for metabolites, which is due to a reduced rate of milk secretion.


Subject(s)
Goats/physiology , Lactation/physiology , Mammary Glands, Animal/physiology , Animals , Blood Flow Velocity , Female , Intercellular Junctions/physiology , Mammary Glands, Animal/blood supply , Mammary Glands, Animal/metabolism , Membrane Potentials , Milk/metabolism , Pregnancy , Time Factors
4.
Am J Surg Pathol ; 17(10): 1062-6, 1993 Oct.
Article in English | MEDLINE | ID: mdl-8372944

ABSTRACT

An aneurysmal bone cyst-like reaction involving the left common carotid artery bifurcation in an otherwise healthy 7-year-old boy is described. The patient presented with a 6-week history of an enlarging pulsatile neck mass. The mass was excised with connection of arteries on either side with a saphenous vein graft. There were no associated intracranial arterial aneurysms or associated skeletal lesions. A history of trauma could not be elicited. To the best of our knowledge this is the first report of an aneurysmal cyst, bone type, involving a large blood vessel.


Subject(s)
Aneurysm/pathology , Bone Cysts/pathology , Carotid Artery Diseases/pathology , Aneurysm/diagnosis , Aneurysm/surgery , Bone Cysts/diagnosis , Carotid Artery Diseases/diagnosis , Carotid Artery Diseases/surgery , Child , Diagnosis, Differential , Humans , Male
5.
J Biochem Biophys Methods ; 12(4): 213-25, 1986 Apr.
Article in English | MEDLINE | ID: mdl-3711586

ABSTRACT

A novel non-invasive technique for measuring the transmembrane currents during action potential depolarizations of stalk segments of the giant unicellular alga Acetabularia mediterranea is described. This involves measurement of spatial samples of the time-dependent potential in the external medium (sea water) and an inverse transformation to give the current distribution at the cell surface. A detailed description of the method of regularization needed to handle this ill-conditioned inversion problem is presented in this paper, along with the results of test experiments to demonstrate its validity. An example of its application to the data recorded from an actual cell is also given.


Subject(s)
Membrane Potentials , Acetabularia/physiology , Action Potentials , Electrodes , Electronics, Medical
6.
Phys Med Biol ; 25(2): 349-55, 1980 Mar.
Article in English | MEDLINE | ID: mdl-7384222
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