Comparison of Micro-ID and Minitek-Serology Systems for Rapid Identification of Salmonella

A 4-h biochemical identification system (Micro-ID) and a rapid confirmation 24-h biochemical and serological procedure (RC) involving the Minitek system were compared for accuracy of Salmonella identification. Of 144 known Salmonella stock cultures, RC correctly classified all, and Micro-ID correctly classified 141. Both systems correctly classified all the Salmonella isolates obtained from four artificially inoculated broiler carcasses. When 113 suspect- Salmonella isolates from naturally contaminated samples were examined, RC correctly classified all, and Micro-ID correctly classified all except one.

Minitek Inoculum Broth for Testing Indole Production by Enterobacteriaceae

With 73 members of the Enterobacteriaceae family, detection of indole production with Minitek inoculum broth (MIB) correlated more closely with the results of the conventional method than did detection with the Minitek H₂S/indole disk.

Sampling of broiler carcasses for Salmonella with low volume water rinse

The uneven distribution and low numbers of salmonella usually present on broiler carcasses make whole carcass rinsing the most sensitive sampling procedure for detecting this organism on the raw product. However, 270 ml of water or medium has been the smallest volume used in past published research. We found that 100 ml was adequate to recover Salmonella typhimurium, S. california, or S. montevideo from freshly processed broiler carcasses that had been inoculated with the organism at the rate of 50 cells/carcass. When carcasses were inoculated with 20 cells or S. heidelberg, then stored at -23 C for 3 or 6 months, sampling with 100 ml was adequate to detect the organism on all carcasses. The advantages of using the smallest volume of rinsing medium that will consistently lead to detection of salmonella present are: 1) less enrichment medium is required, 2) less incubator space is required, and 3) the concentration of cells in the selective enrichment medium at the end of incubation is greater; hence, the greater are the chances of salmonella detection when a drop is subsequently transferred to the selective plating medium.

Modified Procedure to Inoculate Micro-ID

The accuracy of a miniaturized Enterobacteriaceae system (Micro-ID) was evaluated with 10 different genera grown on 11 selective plating media. Whenever growth occurred, the correct identification was made. In addition, 12 serotypes of Salmonella and 22 other strains of Enterobacteriaceae were grown on the two most common selective media used by food microbiologists for isolation of Salmonella [Brilliant Green Sulfa Agar (BGS) and Bismuth Sulfite Agar (BiS)]. The correct identification was made in all instances. The manufacturer of Micro-ID originally recommended that several colonies be picked for inoculation of the system. We modified the inoculation procedure so that only one colony was selected from a plate; this minimized the chances of having a mixed-culture inoculum. With this procedure, all 21 Enterobacteriaceae tested were correctly identified.

Effect of carbohydrate restriction on lipoprotein abnormalities in maturity-onset diabetes mellitus

Hyperlipoproteinemia occurs commonly in diabetics and may contribute to early atherosclerosis in these patients. The effect of dietary carbohydrate restriction on lipid abnormalities has been examined in 42 newly diagnosed maturity-onset diabetics, in whom plasma lipoproteins were measured before treatment was started and at regular intervals during ten months of dietary therapy. Twenty-four patients (57%) had abnormal lipids when diabetes was first diagnosed. Nine were classed as Type II and 15 as Type IV hyperlipoproteinemia. Plasma lipids reverted to normal in half these patients after dietary treatment for one month. Only 8 diabetics (19%) showed persistent lipid abnormality after ten months' treatment: all had been unable to diet satisfactorily as judged by persisting obesity and hyperglycemia. The common lipoprotein abnormalities of maturity-onset diabetes can usually be returned to normal by the simplest possible carbohydrate-restricted diet, if patients adhere to this. Specialized and complex diets or lipid-lowering drugs are unncessary in the majority of patients.

Salmonella on Broiler Carcasses as Affected by Fresh Water Input Rate and Chlorination of Chiller Water

Broiler carcasses, each inoculated with about 1000 cells of a marker strain of Salmonella typhimurium , and uninoculated carcasses were prechilled and chilled in a simulated commercial chilling process. For each experiment, fresh water input was either 1.90 liters (0.50 gal) or 0.95 liters (0.25 gal) per carcass, and the chlorine level was 0, 20 or 50 ppm. The rate of fresh water input had no significant effect on either cross-contamination (uninoculated carcasses showing contamination with marker organisms after chilling) or elimination of Salmonella from the inoculated carcasses. Fewer uninoculated carcasses showed marker Salmonella contamination after chilling with 50 ppm of chlorine than 0 ppm, but cross-contamination was not eliminated. Chlorine in the chilling water decreased rapidly due to the effect of organic matter.

Types of Bacteria and Shelf-Life of Evacuated Carbon Dioxide-Injected and Ice-Packed Broilers

Broiler carcasses were packed in low-permeability film bags that were evacuated, injected with CO₂, then held at 2 C. Broilers were examined microbiologically and for off-odor to determine the shelf-life and types of bacteria. Vacuum level did not significantly affect bacterial counts. Broilers stored in 65% CO₂ had a 1-day longer shelf-life than those held in 20% CO₂ and about a 5-day longer shelf-life than ice-packed broilers. Spoiled carcasses from either 20 or 65% CO₂ packages had an acid-sour off-odor, and more than 90% of the bacteria present were Lactobacillus . Ice-packed broilers had the typical putrid off-odor at spoilage, and more than 95% of the bacteria were non-pigmented Pseudomonas .

Phosphate and heat treatments to control Salmonella and reduce spoilage and rancidity on broiler carcasses

Broiler chicken carcasses were inoculated with about 300 cells of a naladixic acid resistant strain of Salmonella typhimurium, then treated for 3 min with highly agitated water with or without 6% phosphate added, at 65, 70, 75, 80, 85, or 90 C. Other broiler carcasses were inoculated with about 60 cells, then similarly treated at 65 or 70 C. All carcasses were chilled after the hot water treatment in a system simulating commerical chilling. When inoculum was 300 cells, at least 5% of the carcasses remained contaminated with Salmonella, even when hot water treatment was at 90 C. When inoculum was 60 cells, Salmonella were eliminated by hot water treatment at 65 or 70 C. Carcasses showed a partially cooked appearance after hot water treatment. Total bacterial counts on carcasses treated at 70 and 90 C, with or without added phosphate, and then chilled were lower than on control carcasses throughout storage at 2 C for up to 26 days. Phosphates did not consistently or significantly affect either Salmonella survival or total bacterial counts. Oxidative deterioration as measured by the thiobarbituric acid test was significantly retarded throughout 26 days of storage by the addition of 6% phosphate to a 70 or 90 C hot water treatment.

Mesterolone: thrombosis during treatment, and a study of its prothrombotic effects

1. We describe a patient who developed deep vein thrombosis after commencing treatment with the synthetic androgen, mesterolone (Pro-Viron). 2. To investigate the potential thrombogenic action of this drug, a 21 day course of mesterolone (100 mg/day) was given to nine healthy male volunteers. 3. No significant change after treatment occurred in any of the blood tests performed (clotting times, Factor VIII coagulant activity, Factor VIII related antigen, antithrombin III activity, fibrinogen, fibrinogen-fibrin degradation products, plasminogen, euglobulin lysis time, urokinase sensitivity, platelet count, haematocrit, whole blood viscosity and plasma viscosity). 4. We conclude that in a conventional dose taken for 3 weeks mesterolone does not produce a consistent measurable prothrombotic state, nor does it enhance fibrinolysis.

The effect of intravenous heparin infusions on the thyroid stimulating hormone response to thyrotrophin releasing hormone

1 The TSH response to TRH is suppressed 24 h after the commencement of i.v. heparin infusion in euthyroid subjects, as compared to repeat testing, both after 7 days of continuous i.v. heparin and after 7 days without heparin but while on warfarin. 2 This suggests that the rise in serum free thyroid hormones, which heparin produces, has a 'metabolic effect'. Possible clinical effects of this action must be considered. 3 Heparin has no effect on the radio-immunoassay of TSH.

Discrepancies in thyroxine measurement in pregnancy between radioimmunoassay and competitive protein binding (Oxford StaT4)

The StaT4 test is a technically simple test of thyroxine measurement, which apparently gives results in good agreement with those derived by radioimmunoassay in most patients. In pregnancy, however, falsely low serum thyroxine values were found with the StaT4 test when compared with either a radioimmunoassay or the Thyopac-4 test. Detailed studies showed that the discrepancy resulted from the extraction technique used in the StaT4 test, which appears to allow the patient's thyroxine binding proteins to remain in the assay system. Similar method discrepancies were observed in other clinical conditions associated with elevated thyroxine binding globulin concentration. This study, as well as being of practical clinical importance, has implications for the design of competitive protein binding tests of thyroid function.

Effectiveness of Sampling Methods for Salmonella Detection on Processed Broilers

A total of 240 processed broiler carcasses (water-chilled and unfrozen) were each sampled by three methods (whole-carcass rinse, neck-skin rinse, and macerated neck skin) for detection of Salmonella . In addition to this, various procedures were compared: destructive (incubating the entire carcass with the rinse fluid) versus non-destructive (incubating the rinse water with concentrated lactose or selenite cystine broth added after removal of the carcass) sampling and pre-enrichment versus no pre-enrichment during Salmonella detection procedures. There was no significant difference (p < 0.05) between the percentage of Salmonella -positive carcasses obtained by destructive sampling and the percentage obtained by non-destructive samples of whole carcasses. There was also no significant difference (p < 0.05) in results obtained by rinsing and blending excised neck-skin samples. There was highly significant difference (p = 0.001), however, between whole carcass and neck-skin analyses. With whole-carcass sampling, 45% of the carcasses were positive for the presence of Salmonella while with rinsing or blending the neck skin of these same carcasses, only 11% and 12%, respectively, were positive for the organism. Pre-enrichment of the whole carcass, of the whole-carcass rinse, or of the neck-skin samples did not result in significantly greater percentages of positive results than did direct enrichment of these samples.

Hypothalamo-pituitary-thyroid axis function during cardiopulmonary bypass

Marked alterations in levels of circulating thyroid hormone were found in patients undergoing cardiopulmonary bypass with a rise in the free thyroxine and a fall in the free triiodothyronine levels. Studies using thyrotropin-releasing hormone during bypass demonstrated a blunted response to this stimulus. This reduced response is related to changes in thyroid hormone levels and it is suggested that bypass surgery may have a direct inhibitory action on thyroid-stimulating hormone release at the hypothalamo-pituitary level. The potential significance of these hormonal changes is discussed.

1alpha-hydroxyvitamin D3 in primary hyperparathyroidism

The surgical management of primary hyperparathyroidism with severe bone disease (and tertiary hyperparathyroidism) has frequently been complicated by severe and prolonged post-operative hypocalcaemia. In seven such cases a short-pre-operative course of 1alpha-hydroxyvitamin D3 has been found to abolish these adverse features virtually completely and even to diminish pre-operative symptoms where present. Exacerbation of hypercalcaemia has not occurred and this regimen is thus recommended as a routine measure.

Thyroid function in dietary amenorrhoea

Abnormalities of thyroid function are well known to occur in anorexia nervosa. A commoner problem is the patient with secondary amenorrhoea due to weight loss, who does not have true anorexia nervosa. Eight such patients were studied and compared to a normal control group. Total and free thyroxine, total and free triiodothyronine were found to be significantly lower in the amenorrhoea patients. No difference in basal thyroid stimulating hormone or reverse triiodothyronine levels were found. In three of four patients who had thyrotrophin releasing hormone tests performed a prolonged response was found. These results indicate that abnormal thyroid function tests may be found in this milder form of the disease. In addition, the normal reverse triiodothyronine levels suggest the possibility of two mechanisms existing, whereby T3 levels may be lowered in nutritional disorders.

Problems in the diagnosis of Cushing's syndrome

The diagnosis of florid Cushing's syndrome is usually made without difficulty but diagnostic problems may arise. Five such cases are described. Difficulties may occur when the features of the syndrome are incomplete. Three such cases were encountered. In each only one clinical feature was present; these respectively were hypertension, osteoporosis and obesity. The diagnosis was confirmed, however, biochemically and eventually histologically and there was a good response to surgery in each case. Another diagnostic problem, both clinically and biochemically is the obese, hirsute, hypertensive female. Two such cases are described, in whom Cushing's syndrome was diagnosed clinically and biochemically but in whom there was no response to adrenalectomy. Retrospectively the validity of the original diagnosis is questioned. It is concluded that Cushing's syndrome may present in a very incomplete form and should be considered in the differential diagnosis, even if only one feature is present. It is stressed that obesity, hirsutism, hypertension and depression are commonly found in association with normal adrenal function. Urinary free cortisol and cortisol response to insulin induced hypoglycaemia may be of value in distinguishing these cases from those with endocrine disease.

Swab and excised tissue sampling for total and Enterobacteriaceae counts of fresh and surface-frozen broiler skin

Excised broiler skin tissue (12.3 cm 2 area) was (a) blended for various times up to 2 min. or (b) shaken 25, 50, or 75 times with or without sterile glass beads. Blending for 10 sec. or shaking 75 times with glass beads yielded the highest total plate count (TPC) and Enterobacteriaceae count (ENT). Counts did not significantly differ between these methods when freshly processed, unfrozen broiler skin was sampled. However, blending yielded significantly higher TPC and ENT than the conventional sampling procedure or swabbing a 12.3 cm. 2 area of the intact skin for 30 sec. with a calcium alginate swab. When sampling hard chilled (surface frozen) broiler skin, there was no significant difference between shaking and blending for TPC, but shaking gave a significantly higher ENT with less variation than blending. Blending, however, yielded significantly higher TPC and ENT counts than swabbing.