Inactivation of Salmonellae on Chilled and Deep Frozen Broiler Carcasses by Irradiation

Chilled and deep-frozen broiler carcasses were examined for total counts of salmonellae using pooled samples taken from 76 batches each of five birds. By means of a most probable number technique (MPN) it was found that counts expressed/100 g of skin or /500 ml of thaw water varied between < 2 and 1400 with 90% being < 100. Irradiation of carcasses using a dose of 250 krad was found to be highly effective in destroying salmonellae whether the birds had been chilled or deep-frozen.     

No need for preoperative antiseptics in elective outpatient plastic surgical operations: a prospective study

The development of antisepsis in the late nineteenth and early twentieth centuries revolutionized health care. The time-honored technique of skin preparation is to scrub the entire operative area of the patient for 5 to 7 minutes with a germicidal detergent solution and then paint the region with an antimicrobial solution of either tincture of povidone-iodine (Betadine) or chlorhexidine. Although antiseptics result in lower colony counts on the skin, they have side effects and higher cost in relation to normal saline. The authors have prepared patients by showering the surgical site with soap and water and rinsing it with normal saline, in 905 cases of outpatient, clean-wound plastic surgery. In another 905 cases that served as the control group, the traditional method of preoperative shower and scrub with chlorhexidine or Betadine was used. In both groups, there was no incidence of wound infection.     

Studies on Sampling Methods Used in the Control of Hygiene in Poultry Processing

Contamination which occurs at an early stage in the poultry processing line is estimated less accurately by the 'skin-dip' method than by the 'skin-maceration' method. From the results obtained during these studies it is also evident that the bacterial count determined by the method of rinsing the whole carcass cannot be related to counts determined using the skin maceration method.     

The influence of rinsing routines on fluoride retention after toothbrushing

Objective: An important determinant of the anticaries effect of brushing with a fluoride dentifrice is the retention of fluoride in the oral fluids. This study measured the influence of various post‐brushing rinsing routines on fluoride retention. Setting: The Faculty of Odontology, Göteborg University, Sweden. Subjects: Twenty‐one healthy dental students, aged 23±2 yr. Desing: A randomised, cross‐over protocol, comparing various post‐brushing rinsing procedures, with the following variables: volume of rinsing water (5 mL vs. 10×3mL) and duration of rinsing (10 vs. 60 s). Samples of whole saliva, interdental fluid and interdental plaque were analysed for fluoride content. Results: The duration of rinsing did not influence fluoride retention in whole saliva, interdental fluid or interdental plaque. Rinsing with a higher volume of water substantially decreased fluoride retention in all samples. Conclusion: Brushing with a fluoride dentifrice should be followed by rinsing procedures which enhance the retention of fluoride. Rinsing with large volumes of water decreases fluoride retention in the oral fluids, and should be discouraged.     

Membrane Filter Technique for the Quantification of Stressed Fecal Coliforms in the Aquatic Environment

A two-layer membrane filtration (MF) medium (injury-mitigating MF [IM-MF]) and a procedure for the enumeration of injured fecal coliforms are described. These procedures included the addition of glycerol and acetate plus reducing agents to both layers of a two-layer medium and rinsing of the filter with a rich resuscitation medium. Some changes in incubation time and temperatures were used. This method was compared with the multiple-tube fermentation most-probable-number procedure and the one-step M-FC agar-membrane filter method (direct M-FC) in terms of fecal coliform recovery from various aquatic environments that cause bacterial injury. With chlorinated sewage effluents, results of the IM-MF technique were equal to or greater than the most probable number in 9 of 18 trials and were 1.3 to 19 times greater than the M-FC method. When sewage samples were chlorinated in the laboratory, fecal coliform counts with IM-MF equaled or exceeded the most probable number in 7 of 15 trials and always exceeded the M-FC. M-FC was exceeded by IM-MF in 30 of 33 trials with clean mountain stream water. Fecal coliform bacteria that were exposed to low levels of an iodophore in the laboratory produced IM-MF counts 3 to 10 times greater than those with M-FC. A biochemical rationale for the formation of the IM-MF medium is discussed.     

Membrane filter technique for the quantification of stressed fecal coliforms in the aquatic environment.

A two-layer membrane filtration (MF) medium (injury-mitigating MF [IM-MF]) and a procedure for the enumeration of injured fecal coliforms are described. These procedures included the addition of glycerol and acetate plus reducing agents to both layers of a two-layer medium and rinsing of the filter with a rich resuscitation medium. Some changes in incubation time and temperatures were used. This method was compared with the multiple-tube fermentation most-probable-number procedure and the one-step M-FC agar-membrane filter method (direct M-FC) in terms of fecal coliform recovery from various aquatic environments that cause bacterial injury. With chlorinated sewage effluents, results of the IM-MF technique were equal to or greater than the most probable number in 9 of 18 trials and were 1.3 to 19 times greater than the M-FC method. When sewage samples were chlorinated in the laboratory, fecal coliform counts with IM-MF equaled or exceeded the most probable number in 7 of 15 trials and always exceeded the M-FC. M-FC was exceeded by IM-MF in 30 of 33 trials with clean mountain stream water. Fecal coliform bacteria that were exposed to low levels of an iodophore in the laboratory produced IM-MF counts 3 to 10 times greater than those with M-FC. A biochemical rationale for the formation of the IM-MF medium is discussed.     

Cryobiology of neurospora crassa. I. Freeze response of Neurospora crassa conidia

Neurospora crassa conidia were frozen and thawed in water suspensions at various rates and with different minimum temperatures. Colony counts of the experimental conidia were compared with those of controls, which were taken as 100% survival. The data revealed that (1) survivals were near 100% after fast thaw (400 °/min) regardless of the freeze rate, (2) percentage of survival was inversely related to freeze rate when combined with slow thaw, (3) slow thaw (0.5 °/min) was damaging, and (3) the rates of freeze-thaw affected the system only in the −5 to −20 ° interval. The damaging freeze conditions were those which favor ice crystal growth. It is suggested that rupture of the membrane by ice crystals seems to be the plausible mechanism of damage in freezing and thawing N. crassa conidia.     

Optimum Skin Blending Method for Quantifying Poultry Carcass Bacteria

Optimum blending fluids and blending times for use in quantifying bacteria on poultry carcass skin by the skin "blending" method were determined. Butterfield's buffered-phosphate diluent, physiological saline solution (0.85% NaCl), peptone water (0.1% peptone), and deionized water, each at four different skin blending times of 1, 2, 3, and 4 min, were compared. The comparison was based on relative numbers of bacteria per cm(2) of skin, enumerated by each combination on turkey carcasses. Peptone water and physiological saline solution each yielded significantly (P < 0.01) higher bacteria counts from turkey carcass skin samples than did Butterfield's buffered-phosphate diluent or deionized water. There were no significant differences among the four skin blending times and no significant interaction effect between the two factors tested.     

Bacteria in the oral mucosa and its effects on the measurement of cortisol, dehydroepiandrosterone, and testosterone in saliva

Bacteria load in saliva was experimentally manipulated, and the consequences for the measurement of salivary testosterone (T), dehydroepiandrosterone (DHEA), and cortisol (C) were examined. Healthy adults (n = 19) donated the first saliva sample upon rising after which they rinsed their mouths with water, waited 10 min, and donated a second sample. Samples were either left untreated or passed through a 0.22-microm filter and then frozen at -80 degrees C or incubated at room temperature (RT) for 10 days. Aliquots of each sample were cultured on agar to determine baseline and post-incubation (or freezing) bacteria load. Bacteria counts were not significantly influenced by rinsing (with water), were substantially reduced by filtration, and increased by incubation at RT. Average levels of salivary T and C, but not DHEA, were significantly lower in samples stored at RT than samples frozen the day of collection. The change in bacteria count induced by storing samples at RT was associated with a change in testosterone but not cortisol or DHEA. When samples were passed through a 0.22-microm filter bacteria counts were reduced, and the association between bacteria and testosterone was reduced to non-significant. These findings contribute to a growing body of literature revealing that the process of sample collection, storage, and handling can dramatically influence the accuracy of information generated when salivary biomarkers are integrated into research and clinical diagnostics.     

Cometabolism of m-Chlorobenzoate by an Arthrobacter

Swabbing skin to collect bacteria for enumeration revealed that a single washing or rinsing of the swab in buffer removed between 90 and 95% of the bacteria collected. Further removal of the remaining bacteria from the initial swab by repeated washings of the swab produced plate counts that showed nearly proportional decreases in the numbers and types of bacteria retained or eluted from the swab. None of the commonly isolated cutaneous bacteria was retained or eluted from the single swab in numbers that misrepresented measurement of their proportions present in the sample. Populations of nonlipophilic bacteria on skin when present were mainly gram-positive catalase-producing cocci. Diphtheroids when present were chiefly lipophilic. Media containing furoxone were selective for cutaneous diphtheroids. The concentration of furoxone used affected isolation and enumeration of the diphtheroids. Lipophilic diphtheroids from the stratum corneum were basically aerobic and anaerobic incubation reduced or eliminated this group from enumeration studies. Lipophilic furoxone-resistant aerobic diphtheroids from several areas, particularly the nasal passages, occurred in numbers inversely proportional to the numbers of staphylococci for periods up to 11 months. The cocci-diphtheroid relationships occurred independently of the total number of aerobic bacteria present, the transient appearance of yeasts or gram-negative bacilli, the required use of certain antibiotics by the subjects, climate, age, and sex.     

Wound fluid bacterial levels exceed tissue bacterial counts in controlled porcine partial-thickness burn infections

In the present study, an established controlled burn wound model was used to test the hypothesis that controlled surface contamination with is capable of generating a noninvasive method for the creation of a reproducible deep tissue burn wound infection. Using a liquid tight-wound chamber in Yorkshire pigs, partial-thickness burns were inoculated with saline-immersed for 24 hours. Noninoculated burns and unwounded skin immersed in normal saline served as controls. Bacterial cultures of wound fluid were performed daily, and tissue biopsies for bacteriological and histological evaluations were performed on days 1, 3, and 5. was only recovered from -inoculated wounds (tissue and fluid), whereas all controls contained endogenous only. The number of colony-forming units per gram of wound tissue did not correlate with the bacterial counts found in the overlying wound fluid for any wounds. Fluid counts were consistently higher than tissue counts by two logs. -inoculated wounds showed three times deeper tissue destruction than control wounds. Obtaining consistently deep tissue colonization without cross-contamination among wounds, this study introduces a noninvasive model for controlled burn wound infection suitable for future investigations regarding the efficacy of topical antibiotic wound treatment in experimental burns.     

Comparative Enumeration of Lipophilic and Nonlipophilic Cutaneous Diphtheroids and Cocci

Swabbing skin to collect bacteria for enumeration revealed that a single washing or rinsing of the swab in buffer removed between 90 and 95% of the bacteria collected. Further removal of the remaining bacteria from the initial swab by repeated washings of the swab produced plate counts that showed nearly proportional decreases in the numbers and types of bacteria retained or eluted from the swab. None of the commonly isolated cutaneous bacteria was retained or eluted from the single swab in numbers that misrepresented measurement of their proportions present in the sample. Populations of nonlipophilic bacteria on skin when present were mainly gram-positive catalase-producing cocci. Diphtheroids when present were chiefly lipophilic. Media containing furoxone were selective for cutaneous diphtheroids. The concentration of furoxone used affected isolation and enumeration of the diphtheroids. Lipophilic diphtheroids from the stratum corneum were basically aerobic and anaerobic incubation reduced or eliminated this group from enumeration studies. Lipophilic furoxone-resistant aerobic diphtheroids from several areas, particularly the nasal passages, occurred in numbers inversely proportional to the numbers of staphylococci for periods up to 11 months. The cocci-diphtheroid relationships occurred independently of the total number of aerobic bacteria present, the transient appearance of yeasts or gram-negative bacilli, the required use of certain antibiotics by the subjects, climate, age, and sex.     

EFFECTIVENESS OF RINSES IN ALLEVIATING BITTERNESS AND ASTRINGENCY RESIDUALS IN MODEL SOLUTIONS1,2

A two‐part study determined the effectiveness of gum‐based rinses with or without oil for alleviating residuals of a bitter (0.8 g/L caffeine solution) and an astringent (1g/L alum solution) stimuli in serial responses using a sip and spit method. In Experiment 1, rinsing with deionized water was compared to rinsing with 0.3% xanthan gum in water alone or with 5% corn oil and 0.55% carboxymethyl cellulose (CMC) in water alone or with 5% or 10% corn oil. The 0.3% xanthan gum and 5% corn oil mixture resulted in the highest stimulus intensity difference before and after rinsing, whereas 0.55% CMC had a value of nearly zero for residual effect. Results of a two‐alternative forced choice test used in Experiment 2 indicated that both were equally effective for reducing bitterness residuals, but 0.55% CMC solution resulted in the lowest (p=0.007) residual effect for astringency. Therefore, the 0.55% CMC rinse was considered an effective interstimulus rinse to use for assessing both bitterness and astringency in model solutions.     

Substantivity of zinc salts used as rinsing solutions and their effect on the inhibition of Streptococcus mutans

The antimicrobial efficacy of zinc (Zn) salts (sulfate and acetate) against Streptococcus mutans (S. mutans) present in the oral cavity was tested in this study. The substantivity of Zn salts was assessed by determining the concentration of Zn in whole, unstimulated saliva and by measuring the magnitude of suppression of salivary S. mutans, 2h after rinsing. The concentration of Zn was measured by atomic absorption spectrometry (AAS) with electrothermal atomization (ET AAS) in saliva sampled before (basal) and 24h after mouth rinsing with different concentrations of Zn (0.1%, 0.5% and 1%) administrated as sulfate and acetate. The estimation of Zn levels in samples collected 30, 60, 90 and 120 min after rinsing was carried out by AAS with flame atomization (FAAS). Immediately after rinsing, the concentration of Zn in saliva sharply increased with respect to the baseline values (0.055+/-0.017 mg/L), followed by a sustained decrease, probably due to clearance of salivary flow or swallowing during sampling. A significant reduction (>87%) in the total mean S. mutans counts was found 2h after rinsing either with sulfate or acetate solutions, as evidence of the high substantivity and effectiveness of the Zn salts tested. A statistically significant inverse relationship (p<0.001 and the Pearson correlation coefficients between -34% and -50%) was found between Zn levels and the respective pH values measured in the samples collected 60 and 120 min after rinsing, sustaining the theory of bacterial glycolysis inhibition.     

Contamination of foods by food handlers: experiments on hepatitis A virus transfer to food and its interruption

Hepatitis A virus (HAV) is an important pathogen which has been responsible for many food-borne outbreaks. HAV-excreting food handlers, especially those with poor hygienic practices, can contaminate the foods which they handle. Consumption of such foods without further processing has been known to result in cases of infectious hepatitis. Since quantitative data on virus transfer during contact of hands with foods is not available, we investigated the transfer of HAV from artificially contaminated fingerpads of adult volunteers to pieces of fresh lettuce. Touching the lettuce with artificially contaminated fingerpads for 10 s at a pressure of 0.2 to 0.4 kg/cm(2) resulted in transfer of 9.2% +/- 0.9% of the infectious virus. The pretreatments tested to interrupt virus transfer from contaminated fingerpads included (i) hard-water rinsing and towel drying, (ii) application of a domestic or commercial topical agent followed by water rinsing and towel drying, and (iii) exposure to a hand gel containing 62% ethanol or 75% liquid ethanol without water rinsing or towel drying. When the fingerpads were treated with the topical agents or alcohol before the lettuce was touched, the amount of infectious virus transferred to lettuce was reduced from 9.2% to between 0.3 and 0.6% (depending on the topical agent used), which was a reduction in virus transfer of up to 30-fold. Surprisingly, no virus transfer to lettuce was detected when the fingerpads were rinsed with water alone before the lettuce was touched. However, additional experiments with water rinsing in which smaller volumes of water were used (1 ml instead of 15 ml) showed that the rate of virus transfer to lettuce was 0.3% +/- 0.1%. The variability in virus transfer rates following water rinsing may indicate that the volume of water at least in part influences virus removal from the fingerpads differently, a possibility which should be investigated further. This study provided novel information concerning the rate of virus transfer to foods and a model for investigating the transfer of viral and other food-borne pathogens from contaminated hands to foods, as well as techniques for interrupting such transfer to improve food safety.     

Effect of semen thaw method on conception rate in four large commercial dairy heifer herds

Semen processed with procedures intended to permit a flexible thaw method is used to breed millions of cows yearly. One method of thawing straws, the "pocket thaw" is used extensively with semen prepared with these procedures. Published field data is lacking for thaw method comparisons with semen processed to permit flexible-thawing. The objective of the present study was to measure the effect of semen thaw method (warm-water or pocket thaw) over all seasons and its interaction with herds, inseminators, straw package size, and sperm number on conception rate in commercial dairy heifer herds using semen processed with procedures historically optimized for success with flexible-thawing. Professional inseminators performed 11,215 services over a 16-month period in four large herds, achieving a 67.6% conception rate. Thaw method was alternated weekly. Thaw effect on conception status, determined by 70 days non-return rate, was estimated by a generalized linear mixed model. Neither thaw method nor number of sperm per straw significantly affected probability of conception (P=0.658 and 0.769, respectively). No interactions of thaw method with herd, sperm number, season, straw size, and straw size by season were detected (P=0.297, 0.526, 0.365, 0.723, and 0.824, respectively). Bull, herd, inseminator within herd, year, season, and straw size affected conception rate (P=0.002, 0.000, 0.000, 0.000, 0.000, and 0.014, respectively). In conclusion, for semen processed with procedures that permit flexible-thawing, thaw method (pocket thaw versus warm-water thaw) did not affect conception rate under commercial conditions and with routine semen handling methods.     

After-rinsing hair growth promotion of minoxidil-containing amino alpha-cyclodextrins

Triamino alpha-cyclodextrin (CD) was synthesized and the inclusion complex with Minoxidil (MXD) was prepared. alpha-CD was azidated by modifying the 6-hydroxylmethyl CD rim with sodium azide. Then, mono-, di-, tri-, and tetra-azidocyclodextrins were separated by a flash column chromatography and reduced to the corresponding amines by hydrogenation with Pd/C. The substantivities of MXD included in either 2-hydroxypropyl alpha-CD (HP alpha-CD) or triamino alpha-CD were evaluated in vitro using hairless mice skins. After applying the preparations onto the skin and rinsing it, the amount of the drug left on the skin was determined using high-performance liquid chromatography (HPLC). It was the highest when the drug was included in triamino alpha-CD. The electrostatic interaction between the protonated amino CD and the negatively charged skin would be responsible for the relatively high substantivity. The in vivo hair growth promotion effect of each preparation was investigated, where the sample application onto the clipped backs of female mice (C57BL6) and the subsequent rinsing of the backs were done once a day for 30 days. Only MXD in triamino alpha-CD had hair growth promotion effect, possibly due to the significant substantivity.     

Effect of osmotic priming, rinsing and storage on the germination and emergence of carrot seed

Carrot seed, osmotically primed in polyethylene glycol solution (273 g/kg water) for 10 days at 15°C, was given 0–5 rinsing cycles, where each cycle comprised agitating the seed in 10 times its own bulk volume of distilled water for 20 to 30 s. Priming decreased the germination and emergence times whether the seeds were rinsed or not, and these effects were maintained even after storage for 450 days. The number of rinsing cycles had no effects, except that seed given five rinsing cycles deteriorated after 270 days storage.     

Embryonic osmoregulation: consequences of high and low water loss during incubation of the chicken egg

The rates of water loss of domestic chicken eggs were varied during incubation to measure the osmoregulatory ability of the avian embryo. Egg water loss was increased by drilling holes in the eggshell over the airspace on day 13 (I = 21 days) and then placing these eggs in a low relative humidity (r.h.: 0-10%) incubator until hatch. Egg water loss was decreased by placing other eggs in a high-r.h. (85-90%) incubator on day 0. Eggs with low water loss (approximately 6% of initial fresh mass [IFM]) produced embryos and yolks that were not different in wet or dry mass when compared to control eggs that lost approximately 12% of IFM. However, 1-4 gm of excess albumen were left in low-water-loss eggs on day 21. Hatching success was 71% and 89% for low and control eggs, respectively. Low egg water loss did not appear to disturb embryonic growth. The allantoic fluid volume and millimolar allantoic Na+ and Cl- ions declined faster with high and slower with low rates of water loss. Thus, excess water was lost as a result of increased movement of water out of allantoic fluid, which was due to increased active transport of Na+ ions by the chorioallantoic membrane (CAM). Eggs with high water loss had elevated Cl- levels after day 17 in plasma and amniotic fluid, which indicated a period of osmotic stress after depletion of allantoic fluid between day 18 and hatch. The decrease in wet embryo mass measured in embryos from high-water-loss eggs was due principally to dehydration of skin. Embryonic skin may serve as an emergency water reservoir during osmotic stress. Dehydrated chicks produced from high-water-loss eggs were 6 gm less in wet mass at hatch compared to controls. However, these chicks regained the water deficit 7 days after hatch and grew at a rate not different from control chicks through 6 weeks of age. Total egg water loss of 12% of IFM results in highest hatching success. However, water losses between 6% and 20% of IFM do not appear to affect adversely the growth or water content of the chick. Water losses above 20% of IFM cause early depletion of allantoic fluid, prolong the period of osmotic stress, and result in subsequent dehydration of blood, amniotic fluid, and embryonic skin.(ABSTRACT TRUNCATED AT 400 WORDS)