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K L Martin

Publications and source records attributed to K L Martin.

At least 55 records · Page 3Linked to original sources

Differentiation between spores of Bacillus anthracis and Bacillus cereus by a quantitative immunofluorescence technique.

A quantitative immunofluorescence assay based on fiber optic microscopy was used to measure the reaction of formalized spores of Bacillus anthracis and Bacillus cereus isolates with fluorescein conjugates prepared by hyperimmunization with B. anthracis Vollum spores. The spores of 11 of the 20 B. cereus strains reacted with the anti-anthrax conjugate to such an extent that they were indistinguishable from the spores of the several B. anthracis isolates tested. However, absorption of the conjugate with spores of B. cereus NCTC 8035 and B. cereus NCTC 10320 greatly reduced the cross-reaction with the B. cereus preparations so that the mean specific fluorescence of samples of B. cereus spores was in no case higher than 14% of the fluorescence of a reference B. anthracis Vollum preparation.

Absorption↗

Pathology of spontaneous and experimental infection of North American wild ruminants with Mycobacterium paratuberculosis.

Spontaneous paratuberculosis was studied in free-ranging and captive bighorn sheep (Ovis canadensis), and Rocky Mountain goats (Oreamnos americanus). Lesions of paratuberculosis in these species resembled the disease in domestic sheep and goats. Mycobacterium paratuberculosis cultured from bighorn sheep was used to orally infect bighorn x mouflon (Ovis musimon) hybrid sheep, elk (Cervus elaphus nelsoni), mule deer (Odocoileus hemionus), and white-tailed deer (Odocoileus virginianus). Clinical paratuberculosis developed only in mule deer and was characterized by poor growth and diarrhea. Gross lesions were mild in all species. Enlargement of mesenteric lymph nodes was mild to moderate; the wall of the distal small intestine was affected minimally. Focal to diffuse infiltrates of epithelioid macrophages and giant cells occurred in the cortex of mesenteric lymph nodes, around mesenteric lymphatics, and in the intestinal mucosa. Extraintestinal lymph nodes, spleen, liver, and lung were involved in some animals; focal necrosis and mineralization was present in all species but was severe and widespread in the cervids.

Animal Population Groups↗

Experimental infection of some North American wild ruminants and domestic sheep with Mycobacterium paratuberculosis: clinical and bacteriological findings.

Mycobacterium paratuberculosis originally isolated from bighorn sheep (Ovis canadensis) with spontaneous paratuberculosis was used to orally inoculate Rocky Mountain elk (Cervus elaphus nelsoni) calves, mule deer (Odocoileus hemionus) fawns, white-tailed deer (Odocoileus virginianus) fawns, bighorn X mouflon (Ovis musimon) hybrid lambs, and domestic lambs. All experimentally exposed animals became infected. During the first year of infection, hybrid and domestic sheep were able to control the infection but infection was progressive in elk and deer. Clinical paratuberculosis occurred only in mule deer.

Animals↗

Variations on the staining method in quantitative indirect immunofluorescence assays for Bacillus spores, and the use of fluorescein--protein A.

Quantitative indirect immunofluorescence assays for B. anthracis and B. cereus spores fixed on multispot microscope slides have been performed using a microfluorometer to measure the fluorescence of individual bacteria. A study has been made of variations of the indirect assay sequence, in which the washing operation between application of 1st and 2nd antibody types was omitted. In one modification the addition of the indirect antibody was deferred, and in the second the direct and indirect reagents were added simultaneously to the spores at the start of the incubation period. This simultaneous addition method shows promise for wide application in diagnostic serology. Evidence is presented that fluorescein-protein A (F-PA) can be successfully substituted for fluorescein/sheep anti-rabbit antibody (F-SAR) in the indirect spore assay, and that it is far more active than the F-SAR on a weight basis. About twice as many F-PA molecules as F-SAR molecules are bound to the spore at saturation.

Animals↗

Evaluation of a microfluorometer in immunofluorescence assays of individual spores of Bacillus anthracis and Bacillus cereus.

A microfluorometer was constructed by modifying a standard fluorescent microscope with a fibre optic eyepiece and a simple photometric system. It was evaluated in direct immunofluorescence assays of Bacillus anthracis and Bacillus cereus spores immobilised on multispot microscope slides. From measurements of stable fluorescent crystals comparable in size to the spores, it was inferred that the fluorescence intensity of a stained bacterium could be measured with good precision. Fluctuation of a exciting light from a mercury vapour lamp did not contribute significantly to the distribution of fluorescence measurements obtained when samples of 20 spores were assessed. Attempts to correlate spore size with fluorescence intensity suggest that spore fluorescence does not increase in a 1 : 1 ratio with surface area; it is therefore possible that the density of antigenic sites on the surface decreases with increasing spore size. It is concluded that differences in the observed fluorescence of individual spores truly reflect differences in fluorescent antibody binding, but the relative contribution of antigenic variability and of artefacts of the staining procedure remain unknown.

Animals↗

Hyperreninemic hypoaldosteronism in the critically ill: a new entity.

To define the changes in adrenal gland function during critical illness, we evaluated 28 severely ill patients with persistent hypotension who were hospitalized in a medical intensive care unit. The patients had increased plasma cortisol (mean +/- SE, 40.1 +/- 10.1 micrograms/dl). PRA was increased in all subjects (21.6 +/- 7.2 ng/ml.h); however, the plasma aldosterone concentration was inappropriately low in 18 of the subjects, with values ranging from 1-9 ng/dl, despite normal serum potassium concentrations (4.3 +/- 0.1 meq/liter) and increased concentrations of the aldosterone percursor, 18-hydroxycorticosterone. These 18 patients had hypotension associated with major infections and a high mortality rate (78%). Infusions of ACTH or angiotensin II were associated with a normal aldosterone response in only 2 of the 14 patients tested, also suggesting that the defect was probably at the level of the zone glomerulosa cell. Although infection was a common underlying illness, no other factors, such as dopamine administration, decreased angiotensin-converting enzyme activity, or increased aldosterone clearance, could be implicated as the cause of the phenomena. Thus, selective hypoaldosteronism in the presence of high renin levels exists in a substantial percentage of hypotensive critically ill patients.

Acute Disease↗

[Diagnosis, therapy and longterm results of atrial myxoma (author's transl)].

Refering to a case report of five patients with atrial myxoma the symptoms, diagnosis, and therapy of this disease were described. In one case a biatrial tumor was found. In four cases atrial myxoma imitated a mitral-valve disease. An elevated BSR was found in all patients. The non invasive diagnostic procedure of ultrasound-echocardiography led in the last two cases to the correct diagnosis before heart-catheterization. The diagnosis was ascertained in all cases by angiocardiography. If left atrial tumor is suspected transpulmonary laevocardiography can be considered as a save diagnostic procedure better than the direct injection into the left atrium after transseptal puncture. Even the left ventricular angiogram in right anterior oblique position led in four of the five cases to the diagnosis of left atrial tumor. Coronary-angiography was performed in three patients and revealed pathologic atrial vessels in all three cases. Immediate operation is the indicated therapy. Two of the five patients were reviewed over a eight year period after operation without any signs of recurrence of the tumor.

Adult↗

[Accuracy of exercise tests in the recognition of coronary-artery stenosis. Comparison between post-exercise ECG and coronary arteriogram (author's transl)].

Post-exercise ECGs and coronary arteriograms were compared in 180 unselected patients. Coronary-artery stenosis had been diagnosed correctly by arteriography in 94% of cases. In 60% this was also possible from the resting ECG (signs of myocardial infarction), while in the remaining 34% only the exercise ECG was positive. Post-exercise ECG changes are thus an important and largely specific means of diagnosing coronary-artery stenosis.

Adult↗