Search PubMed⌕ Search

Biomedical subjects

S M Russell

Publications and source records attributed to S M Russell.

At least 19 recordsLinked to original sources
PubMed1999

Effect of chemical cleaning agents and commercial sanitizers on ATP bioluminescence measurements.

Nine chemical cleaning agents at three concentrations were studied to determine the effect on ATP bioluminescence measurements from pure ATP (PATP) and ATP from chicken exudate (CJATP). The nine commercial cleaning and sanitizing chemicals were concentrated foaming acid (FA), acid sanitizer (AS), iodine cleaner-disinfectant (ZI), alkaline cleaner-degreaser (PC), chlorinated alkaline cleaner (CA), chlorinated sanitizer (CS), quaternary ammonium (QA), antibiofilm agent (AB), and acidic peroxygen sanitizer (HP). Effect was reported as a percent change from the log10 relative light unit (LRLU) measurements of the control groups. All cleaners and sanitizers were tested at one-tenth of the manufacturer's recommended level (MRL), MRL, and two times MRL. FA, PC, and CA at all three concentrations significantly decreased PATP and CJATP LRLU. AS decreased PATP and CJATP LRLU at 200 and 400 ppm quaternary ammonium. ZI decreased PATP LRLU at MRL or greater, while CJATP LRLU were decreased by all concentrations of ZI tested. CS decreased PATP LRLU in a dose-dependent manner; however, for CJATP, LRLU decreased slightly at the two lower concentrations but were not affected by 1,200 ppm CS. QA at MRL or above for PATP or at all concentrations for CJATP significantly increased LRLU. AB decreased LRLU at all concentrations tested for PATP or at MRL or greater for CJATP. HPA at MRL or greater for PATP or at all concentrations for CJATP significantly reduced LRLU. These results demonstrate that commercial sanitizers and cleansers may squelch or increase LRLU measurements when the chemical comes into direct contact with the ATP bioluminescence reagents. Hence, when using ATP bioluminescence as a means of determining sanitary quality of food-processing equipment, it is essential to consider the type and concentration of chemical cleaner or sanitizer being used on the equipment prior to testing.

Adenosine Triphosphate↗
PubMed1998

Delineation of the regions of interleukin-2 (IL-2) receptor beta chain important for association of Jak1 and Jak3. Jak1-independent functional recruitment of Jak3 to Il-2Rbeta.

Interleukin-2 (IL-2) induces heterodimerization of the IL-2 receptor beta (IL-2Rbeta) and gammac chains of its receptor and activates the Janus family tyrosine kinases, Jak1 and Jak3. Whereas Jak1 associates with IL-2Rbeta, Jak3 associates primarily with gammac but also with IL-2Rbeta. We analyzed four IL-2Rbeta mutations that diminish IL-2-induced proliferation and found that each also decreased IL-2-induced signal transducer and activator of transcription (STAT) activation. For this reason, and because the mutations were in the IL-2Rbeta membrane-proximal region, we investigated and found that each mutation diminished IL-2Rbeta association with both Jak1 and Jak3. This suggested that these Jaks might interact with the same region of IL-2Rbeta; however, certain IL-2Rbeta internal deletions and C-terminal truncations differentially affected the association of Jak1 and Jak3. Interestingly, just as Jak1-IL-2Rbeta association is Jak3-independent and functionally important, we show that Jak3-IL-2Rbeta association is Jak1-independent and implicate this association as being important for IL-2-induced Stat5 activation. Moreover, Jak1 and Jak3 could associate only in the presence of IL-2Rbeta, suggesting that these kinases can simultaneously bind to IL-2Rbeta. Thus, our data not only demonstrate that somewhat more distal as well as membrane-proximal cytoplasmic regions of a type I cytokine receptor are important for Jak kinase association but also suggest that two IL-2Rbeta-Jak kinase interactions are important for IL-2 signaling.

Animals↗
PubMed1998

Bloodless medicine and surgery.

Our hospital is a center for bloodless medicine and surgery (CBMS). It is one of 56 such centers located in the United States. The mission of the center is to provide surgical and medical treatment without the administration of blood or blood-related products. Patients' rights to autonomy and self-determination are respected. Development of the CBMS program required the writing and implementation of specific guidelines, developing standards of care, revising existing policies and procedures, and educating staff members. The CBMS program is multifaceted and multidisciplinary.

Advance Directives↗
PubMed1998

The relationship of broiler breast color to meat quality and shelf-life.

A total of three experiments were conducted to compare physical and microbiological properties of raw and marinated broiler breast fillets selected as being either lighter or darker than normal. Visibly light- and dark-colored breast fillets were divided into marinated and control groups, and vacuum-tumbled for 20 min at 4 C under 80 kPa pressure. Breast fillets from the four treatment groups were evaluated for shear values, raw and cooked meat pH, drip-loss, cook-loss, water-holding capacity, and 7 d psychrotrophic count. The light-colored fillets were significantly lighter, less red, and more yellow than the dark fillets. Lightness values increased when fillets were marinated. Moreover, the light fillets had a lower pH than dark fillets. The pH values of raw and cooked breast meat were related to meat color but not marination. Dark-colored fillets had significantly higher marination pick-up and a higher fraction of bound moisture and significantly lower drip and cook-loss. No differences were observed in shear values between color or marination treatments. There were no significant differences in psychrotrophic plate counts (PPC) or capacitance detection times (CDT) due to color or treatment at Day 1. After 7 d of storage at 4 C, PPC was significantly lower for marinated samples. No correlations were observed between pH and PPC, CDT, or odor. Based on these differences in physical and microbiological properties, further processors may consider separating breast fillets according to color.

Animals↗
PubMed1998

A rapid microbiological method for enumerating Escherichia coli from broiler chicken carcasses.

Experiments were conducted to evaluate a rapid method for enumerating Escherichia coli from broiler chicken carcasses. In three separate trials, carcasses were obtained from a commercial processing plant, temperature abused at 37 degrees C for 0, 3, 6, 9, or 12 h, and then rinsed. E. coli were enumerated from carcass rinses using Petrifilm E. coli count plates (PC) and by placing the rinse into double-strength colifiform medium supplemented with 2% dextrose (CMD). The CMD mixture was placed into a Bactometer module and conductance was measured at 44 degrees C. Once a detection time (DT) was recorded, the sample was immediately recovered from the module well, diluted, and spread onto plate count agar. Colonies on plates at the highest dilution from each module well were randomly selected and identified. After 0, 3, 6, 9, and 12 h of temperature abuse, E. coli was the bacterial species identified 97, 92, 88, 87, and 61% of the time, respectively. These results indicate that the medium/temperature combination was excellent for enumerating E. coli from samples that contain mixed microflora using conductance. Significant linear correlations were observed between time of abuse (TA) and log10 PC (LPC) or DT (R2 = 0.86 and R2 = -0.90, respectively). A significant linear correlation was observed between LPC and DT (R2 = -0.92). This rapid method (1 to 7.6 h) for enumeration of E. coli on chicken should provide a way to determine E. coli levels before a product is shipped, and it should aid the poultry industry in meeting the E. coli testing requirement of the U.S. Department of Agriculture Food Safety and Inspection Service pathogen reduction regulation.

Animals↗
PubMed1998

Acid tolerance and acid shock response of Escherichia coli O157:H7 and non-O157:H7 isolates provide cross protection to sodium lactate and sodium chloride.

The survival of Escherichia coli O157:H7 and non-O157:H7 due to an enhanced acid tolerance response (ATR), and enhanced acid shock response (ASR), or the stationary phase protective system when exposed to lactic acid and the resulting cross protection against increased concentration of sodium chloride and sodium lactate was studied. Escherichia coli O157:H7 isolates (1932 and 009) and a non-O157:H7 strain (ATCC 23716) were grown to stationary phase at 32 degrees C and O157:H7 to one of two treatments in an attempt to either acid shock or acid adapt the survivors. Acid shocked cells were exposed to lactic acid at pH 4.0. Acid-adapted cells were first exposed to a pH of 5.5 and then an acid challenge of pH 4.0. Sodium lactate (10%, 20%, or 30%) or sodium chloride (5%, 10%, or 15%) were added to a minimal glucose medium after the acidification treatment. When acid shocked and acid adapted isolate 932 and strain ATCC 23716 tolerated the elevated levels of sodium lactate, and the strain ATCC 23716 tolerated the elevated levels of sodium chloride. Acid adaption allowed isolate 932 to tolerate higher levels of sodium chloride; however, the acid shocking did not provide the same protection. Neither of the acid treatment provided increased tolerance to sodium chloride for isolate E009. Evidence of cross protection against acid and sodium chloride or acid and sodium lactate in E. coli O157:H7 could point to a need for further evaluation of whether these combinations of preservation means are sufficient to control this pathogen.

Escherichia coli O157↗
PubMed1998

Capacitance microbiology as a means of determining the quantity of spoilage bacteria on fish fillets.

An experiment was conducted to determine if a method for enumeration of Pseudomonas fluorescens in less than 11 h could be used to predict potential spoilage of fresh fish of for species. In each of three separate replications (Rep), five boneless fillets from each species of fish, including rainbow trout (RT), Atlantic salmon (AS), red grouper (RG), and tilapia (T) were obtained fresh from a retail outlet. For each species, six 25-g samples of fish flesh were asceptically removed from each fillet, placed into a polyethylene bag, and stored at 3 degrees C for 0, 1, 2, 3, 4, or 5 days. After storage, samples were analyzed for psychotrophic plate count (PPC), Pseudomonas fluorescens plate counts (PFPC), and P. fluorescens capacitance detection times (PDT) and subjectively evaluated for odor (ODOR). PPC gradually increased on all fish species as storage time increased. In most cases, PFPC decreased slightly and then progressively increased as storage time increased. In Reps 1 and 2, PDT decreased gradually (indicating an increase in bacteria); however, in Rep 3, PDT were erratic and difficult to interpret. Odor increased gradually throughout the storage period for all fish species. Linear correlations (R2 > 0.80) were observed between PPC and day of storage (DAY) for all fish species and Reps except for RT and RG in Rep 3. PFPC correlated (R2 > 0.70) to DAY for all fish except RT in Rep 3 and RG in Rep 2. PDT was negatively correlated to DAY for RT and T in Rep 1 and for all fish in Rep 2. Odor scores were highly correlated (R2 > or = 0.84) to DAY for all fish tested. PPC and PDT were negatively correlated for RT in Reps 1 and 2, AS in Rep 2, and T in Reps 1 and 2. Because results can be obtained in < 12 h, the capacitance procedure with further refinement may provide an excellent alternative to conducting PPC as a means of predicting potential spoilage of fish such that the fillets of inferior quality (i.e., those that will spoil rapidly) may be sent to distribution outlets that are known to move fish products quickly and are able to sell the fish before it spoils.

Animals↗
PubMed1998

Effect of chemical sanitizing agents on ATP bioluminescence measurements.

Experiments were conducted to determine the effects of sodium hypochlorite (SH), quaternary ammonium (QA), trisodium phosphate (TSP), lactic acid (LA), hydrogen peroxide (HP), and trichlosan (TR) on ATP bioluminescence measurements. Each sanitizer was tested at three different levels and compared to a control group containing no sanitizer. ATP from three sources was analyzed, Escherichia coli, chicken blood, and a pure ATP standard. The effect of each sanitizer was reported as a percent decrease in log10 relative light units (LRLU) for the treatment groups when compared to LRLU from the control groups. SH concentrations of 30, 50, and 70 ppm and quaternary ammonium at concentrations of 10, 20, and 30 ppm had no effect on LRLU measurements, regardless of the ATP source. LA concentrations of 0.5% and higher reduced LRLU by 75%. LRLU measurements were significantly (P < or = 0.05) reduced by approximately 60% when levels of TSP exceeded 1%. HP had no effect on LRLU measurements from any of the ATP sources at 0.1%; however, at 1% HP significantly (P < or = 0.05) decreased LRLU measurements by approximately 60% for all ATP sources. TR at 0.25% had no significant effect on LRLU measurements from any of the ATP sources. TR at 0.5 and 1% reduced LRLU measurements by 30 and 50%, respectively. These results indicate that commercial sanitizers containing LA, TSP, HP, or TR may negatively affect LRLU measurements if the sanitizer is allowed to come into direct contact with the ATP bioluminescence reagents.

Adenosine Triphosphate↗
PubMed1997

The effect of evisceration on visible contamination and the microbiological profile of fresh broiler chicken carcasses using the Nu-Tech Evisceration System or the conventional Streamlined Inspection System.

Experiments were conducted to determine the effect of evisceration on visible contamination and the microbiological profile of fresh broiler chicken carcasses using the Nu-Tech System or the Streamlined Inspection System (SIS). Visible contamination was evaluated on the inside cavity and outside surface of 1,000 and 7,825 carcasses from Plants A and B, respectively, during 5 d of processing. For the microbiological study, in five separate trials, 80 broiler carcasses were collected each day from two processing plants (A and B). Two groups of 20 carcasses each were collected immediately prior to entering the Nu-Tech eviscerator, bagged separately, and 20 were labeled as NT1 and 20 as SIS1. The third group of 20 carcasses was collected immediately after the cropper on the Nu-Tech line and labeled NT2. For the fourth group, 20 carcasses were aseptically transferred from the Nu-Tech line just prior to evisceration, placed on the SIS line prior to evisceration, allowed to be eviscerated by the SIS eviscerator, collected immediately after the cropper, and labeled SIS2. Whole carcass rinses were conducted and aerobic plate counts (APC), total coliform counts (TC), total Escherichia coli counts (TEC), aerobic mesophilic impedance detection times (DT), and coliform impedance detection times (CDT) were determined within 30 h of collection. The Nu-Tech System was superior to SIS with regard to visible carcass contamination. For Plant A, evisceration using the Nu-Tech System or SIS did not significantly affect APC, TC, or TEC; however, evisceration using the Nu-Tech System resulted in an increase in DT and CDT (indicating a reduction in bacteria); whereas evisceration using SIS resulted in no significant decrease in bacterial levels. For Plant B, evisceration using the Nu-Tech resulted in lower APC, TC, TEC, and higher DT and CDT (indicating a reduction in bacteria); whereas evisceration using SIS resulted in no significant decrease in bacterial levels. Evisceration using the Nu-Tech System was at least equal to or in some cases better than SIS with regard to APC, TC, TEC, DT, and CDT.

Abattoirs↗
PubMed1997

The relationship of broiler breast meat color and pH to shelf-life and odor development.

Experiments were conducted to compare the shelf-life of dark-colored and light-colored broiler breast meat. In each of three trials, 100 breast fillets were obtained from a commercial processing plant and subjectively categorized as "dark" or "light". The 100 fillets were then objectively evaluated for C.I.E. color values (lightness, redness, and yellowness). The fillets were separated into five storage groups, with each group containing 10 dark and 10 light fillets, and the fillets were held at 3 C for 0, 3, 6, 9, and 12 d. On each sampling day, fillets were evaluated in duplicate for psychrotrophic plate count (PPC), capacitance detection time (CDT), pH, and subjective odor evaluation. Dark fillets had significantly (P < 0.05) lower lightness values (L*), higher redness values (a*), lower yellowness values (b*), and higher pH values. Regression coefficients for odor scores resulted in darker fillets having significantly (P < 0.05) higher slopes than lighter-colored fillets even though intercept values were similar. Significant correlations existed between pH and color as well as odor, CDT, and PPC. These data suggest that darker broiler breast meat fillets have a shorter shelf-life than lighter breast fillets; the shorter shelf-life may be due to differences in pH.

Animals↗
PubMed1996

Different interleukin 2 receptor beta-chain tyrosines couple to at least two signaling pathways and synergistically mediate interleukin 2-induced proliferation.

One of the earliest events induced by interleukin 2 (IL-2) is tyrosine phosphorylation of cellular proteins, including the IL-2 receptor beta chain (IL-2Rbeta). Simultaneous mutation of three tyrosines (Y338, Y392, and Y510) in the IL-2Rbeta cytoplasmic domain abrogated IL-2-induced proliferation, whereas mutation of only Y338 or of Y392 and Y510 inhibited proliferation only partially. While Y392 and Y510 were critical for IL-2-induced activation of signal transducers and activators of transcription (STAT proteins), Y338 was required for Shc-IL-2Rbeta association and for IL-2-induced tyrosine phosphorylation of Shc. Thus, activation of both Jak-STAT and Shc-coupled signaling pathways requires specific IL-2Rbeta tyrosines that together act in concert to mediate maximal proliferation. In COS-7 cells, overexpression of Jak1 augmented phosphorylation of Y338 as well as Y392 and Y510, suggesting that the role for this Jak kinase may extend beyond the Jak-STAT pathway.

Adaptor Proteins, Signal Transducing↗
PubMed1996

A dissection of the chapter "Tools for Research" in Peter Singer's Animal Liberation.

The book Animal Liberation, by philosopher Peter Singer, is frequently referred to as the bible of the animal liberation/rights movement(ALARM). Thus, Singer is regarded as a major moral standard-bearer of the ALARM. Some have suggested that his book provides "intellectual rigor" to the moral arguments for animals' equality with humans, which had previously been based largely on emotionalism and sentimentality. We have analyzed the contents of the chapter "Tools for Research" which criticizes the use of animals in biomedical research as well as for drug and product-safety testing. In order to discredit these practices, Singer "documents" his arguments with 138 "notes", some of which are to the same reference and others of which contain multiple references. Of the 132 difference references, we attempted to verify the accuracy of 49 of them. Of these, 16 (33%) were inaccurate or we could not find. In addition, Singer mischaracterizes the cited studies in various ways. He quotes selectively and out of context from numerous research projects. He never mentions the objectives of these projects, except occasionally when, in our opinion, he distorts or trivializes them. Singer also cites supposedly damning "evidence" published by other antivivisectionists, even though this "evidence" has been refuted in the literature. Singer supposedly embraces utilitarianism, a philosophy which holds that the harm done by a practice should be balanced against the gain realized from it. However, he makes virtually no attempt to consider objectively the benefits that have been realized from animal-based medical research and he greatly exaggerates the costs. To him, animal research is "all pain and no gain." We believe that Singer's moral arguments for animal equality are not convincing. The lack of objectivity and the reliance upon distortion and selective quotation that characterize Singer's "scholarship" are surprising when one considers that he presents himself as an ethicist and moralist.

Animal Rights↗
PubMed1996

The effect of temperature mishandling at various times during storage on detection of temperature abuse of fresh broiler chicken carcasses.

Experiments were conducted to determine the effect that temperature mishandling at various times during storage has on detection of temperature abuse of fresh broiler chicken carcasses using populations of mesophilic and coliform bacteria as indicators of abuse. Forty-five broiler carcasses were used in each of three independent trials. Five carcasses were analyzed at day of collection (Treatment 0 control). Five carcasses, on each day of the next 7 d (Treatments 1 to 7) were temperature-abused for 12 h at 25 C, stored at 3 C until Day 9, and then sampled. The five remaining carcasses were stored at 3 C and sampled on Day 9 (Treatment 8 control). Carcasses were sampled using a whole carcass rinse procedure and assayed for aerobic plate counts (APC), total coliform counts (TCC), impedance detection times (DT), and impedance coliform detection times (DTCM). Although significant differences were noted using all four microbiological methods, temperature abuse at different times during storage had no consistent effect on populations of mesophilic or coliform bacteria; therefore, temperature abuse determinations may be conducted without regard to the day on which the carcasses were subjected to elevated temperatures.

Animals↗
PubMed1995

Mutation of Jak3 in a patient with SCID: essential role of Jak3 in lymphoid development.

Males with X-linked severe combined immunodeficiency (XSCID) have defects in the common cytokine receptor gamma chain (gamma c) gene that encodes a shared, essential component of the receptors of interleukin-2 (IL-2), IL-4, IL-7, IL-9, and IL-15. The Janus family tyrosine kinase Jak3 is the only signaling molecule known to be associated with gamma c, so it was hypothesized that defects in Jak3 might cause an XSCID-like phenotype. A girl with immunological features indistinguishable from those of XSCID was therefore selected for analysis. An Epstein-Barr virus (EBV)-transformed cell line derived from her lymphocytes had normal gamma c expression but lacked Jak3 protein and had greatly diminished Jak3 messenger RNA. Sequencing revealed a different mutation on each allele: a single nucleotide insertion resulting in a frame shift and premature termination in the Jak3 JH4 domain and a nonsense mutation in the Jak3 JH2 domain. The lack of Jak3 expression correlated with impaired B cell signaling, as demonstrated by the inability of IL-4 to activate Stat6 in the EBV-transformed cell line from the patient. These observations indicate that the functions of gamma c are dependent on Jak3 and that Jak3 is essential for lymphoid development and signaling.

Amino Acid Sequence↗
PubMed1995

Expression of interleukin-2 receptor gamma on human monocytes: characterization of lineage specific post-translational modifications.

Functional interleukin-2 receptors (IL-2R) on lymphocytes contain both IL-2R beta and gamma chains. Whereas constitutive expression of IL-2R beta has been found on monocytes, the expression of IL-2R gamma on these phagocytes has not been examined. We performed reverse-transcription-polymerase chain reaction with Southern blot analysis on RNA derived from purified human monocytes and discovered that they constitutively produce IL-2R gamma mRNA. Western immunoblotting revealed 58- and 64-kDa forms of IL-2R gamma on YT-1 and human monocytes, whereas 58-, 64-, and 69-kDa bands were detected using peripheral blood mononuclear cells and non-adherent lymphocytes. These different forms resulted from variable N-linked glycosylation since culture of the cells in tunicamycin resulted in detection of a single 39-kDa band which corresponds to the molecular weight predicted from the deduced amino acid sequence. By co-immunoprecipitation, the IL-2R beta subunit associates with only the 64-kDa IL-2R gamma protein band in monocytes.

Blotting, Southern↗
PubMed1995

Defective lymphoid development in mice lacking expression of the common cytokine receptor gamma chain.

The common gamma chain (gamma c) of the IL-2, IL-4, IL-7, IL-9, and IL-15 receptors is defective in humans with XSCID. Mice lacking gamma c expression had hypoplastic thymuses; the thymocytes responded to gamma c-independent mitogens, but not gamma c-dependent stimuli. Splenic T cells were diminished at 3 weeks of age, but CD4+ T cells markedly increased by 4 weeks. B cells were greatly diminished in contrast with the situation in XSCID. NK cells, gamma delta intestinal intraepithelial lymphocytes, dendritic epidermal T cells, peripheral lymph nodes, and gut-associated lymphoid tissue were absent. These findings underscore the importance of gamma c in lymphoid development. Moreover, differences in humans and mice lacking gamma c expression indicate species-specific differences in the roles of gamma c-dependent cytokines or in the existence of redundant pathways. These mice provide an important model for studying the pathophysiology provide an important model for studying the pathophysiology of and gene therapy for human XSCID.

Animals↗