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Biomedical subjects

C M Papa

Publications and source records attributed to C M Papa.

At least 19 recordsLinked to original sources

Post-mortem biochemistry of Pekin duckling and broiler chicken Pectoralis muscle.

Biochemical post-mortem changes between red and white avian muscle were determined using duckling and chicken Pectoralis muscles, respectively. Six live Pekin ducklings and six live broiler chickens, in each of two trials, were obtained from commercial plants and processed at a pilot facility. After evisceration, carcasses were held at 4 C, then Pectoralis muscles were removed at .25, 1, 4, and 24 h post-mortem, and sampled for pH, lactate, adenosine triphosphate (ATP) content, and R-value (inosine to adenine ratio). Duckling Pectoralis pH significantly (P less than .05) decreased from 6.25 to 5.66 from .25 to 24 h post-mortem, respectively, as compared with that of the chicken, which decreased from 6.41 to 5.62 for the same times. Duckling lactate values, from .25 to 24 h, increased from 15.86 to 28.86 mumol/g, respectively, and chicken lactate values increased from 27.62 to 53.51 mumol/g. The ATP content of the duckling Pectoralis muscle decreased from 1.59 to .14 mumol/g and chicken Pectoralis decreased from 3.42 to .21 mumol/g from .25 to 24h, respectively. The R-values of duckling and chicken Pectoralis significantly increased from .25 to 24 h (.98 to 1.37 and .80 to 1.51, respectively). Duckling and chicken biochemical measurements were significantly different at all post-mortem sampling times, except for 24-h values of pH (5.66 versus 5.62, respectively) and 24-h contents of ATP (.14 versus .21 mumol/g, respectively). The different post-mortem biochemical measurements between duckling and chicken Pectoralis muscle is evidence that different rates of post-mortem metabolism and rigor development exist between these red and white avian breast muscles.

Adenine

The presence of Yersinia enterocolitica and other Yersinia species on the carcasses of market broilers.

Sixty ready-to-cook broiler carcasses obtained from several local supermarkets were tested for the presence of Yersinia enterocolitica and other Yersinia species. In the present study, the authors used two enrichment broths, yeast-extract/rosebengal-bile oxalate sorbose (YER-BOS) and phosphate-buffered saline with a postenrichment KOH treatment (PBS-KOH), and two plating media, cefsulodin-irgasan-novobiocin (CIN) and pectin agar. Yersinia organisms were found on 34 of 60 carcasses (56.7%) and Y. enterocolitica, on 16 of 60 carcasses (26.7%). There was no significant difference between CIN and pectin agar; however, PBS-KOH yielded a significantly higher (P less than or equal to .05) detection rate than YER-BOS, regardless of the plating media used. In addition to Y. enterocolitica, Y. frederiksenii and Y. intermedia were also isolated from the market broilers. None of the Y. enterocolitica isolates were found to be presumptively virulent.

Animals

Comparison of microscopic and laser diffraction methods for measuring sarcomere lengths of contracted muscle fibers of chicken pectoralis major muscle.

The objective of the present study was to compare the effectiveness of a microscopy method with a laser diffraction method for measuring sarcomere lengths of chicken pectoralis major (p. major) muscle fibers exhibiting various contraction states. Chicken p. major muscles were excised from the animals at death. Samples of each muscle were treated with pH-buffered (5.0 and 7.5) isoionic CaCl2, KCl, or ethylene glycol bis-(b-aminoethyl ether) N,N,N',N'-tetraacetic acid (EGTA) solutions in order to produce variability in the degree of fiber contraction. Sarcomere lengths (SL) of the fibers were observed using light microscopy and a laser diffraction method. The methods gave comparable results for sarcomere lengths greater than 1.6 microns. However, for SL less than 1.6 microns, sarcomere contraction was not accurately assessed by the laser diffraction method.

Animals

Influence of sodium pentobarbital on pH, sarcomere length, and muscle tenderness of broiler Pectoralis major muscle.

Six trials were conducted to determine the effect of sodium pentobarbital (SP) anesthesia on broiler muscle pH, sarcomere length, and Allo-Kramer shear values. Birds were divided into six groups, three of which were anesthetized with SP prior to slaughter. Birds from both the anesthetized and nonanesthetized groups were subjected to one of three processing treatments: 1) muscles hot boned as soon as possible after death and immediately analyzed (HB/0); 2) muscles hot boned and aged 24 h in ice/water slush (HB/24); and 3) muscles left on carcass (conventional process) and aged 24 h in ice/water slush (CP/24) before deboning. The SP/HB/0 group was found to have significantly higher (P less than .05) pH values and longer sarcomere lengths than those of the other five treatment groups. No significant differences were observed for pH among the four 24-h aged groups. Sarcomere lengths were found to be shortest in the SP/HB/24 and HB/24 groups followed by SP/CP/24, HB/0, and CP/24 groups. The CP/24 and SP/CP/24 groups had the lowest shear values, with the HB/0, HB/24, and SP/HB/24 groups exhibiting three-fold higher shear values. These results indicate that SP can delay the effects of ante-mortem stress on early rigor processes; however, no such effects were apparent following 24-h aging.

Animals

Effects of electrical stimulation on the post-mortem biochemical changes and texture of broiler pectoralis muscle.

A study was conducted to determine the influence of electrical stimulation (50,200, or 350 V ac) on biochemical and textural changes in broiler breast muscle. Sixty-four broilers were stunned (50 V ac) prior to kill, and all but a control group were pulse stimulated during bleeding. After processing, carcasses were held in 10-C water for 1 h, then in 2-C ice/water slush for 1 h prior to muscle removal at 2 h post-mortem (PM). Bagged samples were held at 2 C for 24 h, then cooked. The pH, R value (ratio of adenine nucleotides to inosine nucleotides), cook yield, fluids and solids lost (F&S), and objective texture were measured. In addition, 16 broilers processed in the same manner were used in producing a profile of sarcoplasmic protein/enzyme changes in the breast muscle by cation exchange fast protein-liquid chromatography at 10 min, 2, and 24 h PM. The R values and soluble protein were also determined. Stimulation at 200 and 350 V accelerated the onset of rigor noted by lower pH values at 10 min and 1 h PM, and higher R values at 2 h PM. Muscle stimulated at 350 V exhibited the lowest cook yield and highest percentage of F&S lost, suggesting both the loss of functional properties and muscle integrity due to this treatment. All control and stimulated samples exhibited shear values in excess of what would be considered tender. Hardness and chewiness values increased as stimulation voltage levels increased. Only one of the seven principal chromatographic peaks decreased in response to increased electrical stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenine Nucleotides

Early post-mortem metabolism and muscle shortening in the Pectoralis major muscle of broiler chickens.

Three experiments were conducted to examine the effects of sodium pentobarbital (SP), iodoacetate (IO), tubocurarine (TC), and surgical denervation (DN) on early rigor development in broiler breast muscle. In Experiment 1, birds were either anesthetized or not with SP before receiving an injection of IO or TC or maintained as noninjected controls. Experiment 2 was identical except that a treatment of denervation of the breast muscle was added. Experiment 3 was conducted to contrast birds at 1 day (DN1) and 3 days (DN3) denervation prior to slaughter to nonoperated controls. Measurements of muscle lactate, ATP, R value (ratio of inosine to adenine nucleotides), pH, sarcomere lengths, and shear were used to evaluate treatment effects. Results for Experiment 1 showed no significant differences among treatment and control groups for ATP and lactate contents, R values, or sarcomere lengths; however, significantly lower pH and higher shear values were observed for control birds. In Experiment 2, no significant differences were observed among the treatment groups for ATP, R values, or sarcomere lengths. However, lactate and shear values were significantly lower, and pH higher, for the DN and SP treated birds. Experiment 3 resulted in lower lactate and higher pH values for the DN3 treatment in comparison with both DN1 and control groups. Results of these studies indicate that the use of SP and DN can be used to alter the early profiles of rigor development.

Animals

Lower gut contents and defecatory responses of broiler chickens as affected by feed withdrawal and electrical treatment at slaughter.

The study was conducted to investigate a method of reducing the potential for fecal contamination during slaughter of broiler chickens. Birds were withdrawn from feed for 4, 8, 12, or 16 h before slaughter, then subjected to an electrical treatment of either stunning at 50 V, stunning plus pulsed stimulation at 50 V, or electrocution at 200 V. Peri-mortem defecatory responses were characterized, and postmortem examinations of the lower gut contents were made. Results indicated significant increases for the following variables when analyzed as linear functions on time of feed withdrawal: 1) loss of body weight (expressed as shrink); 2) amount of excreta collected during withdrawal; and 3) frequency and amount of perimortem excretions. Cecal material was observed in the colon most often for the group withdrawn 4 h from feed. Among electrical treatments, electrocution resulted in the lowest frequency of excretion, the smallest amount of excreta, and a greater tendency toward more urinous excreta; however, these results were significantly different from only the treatment of stimulation. There were no significant differences detected among electrical treatment for contents of the various segments of the lower gut. Potential for the use of electrocution to reduce fecal loads during commercial slaughtering conditions was not conclusively demonstrated.

Animals

NJ skin cancer screening program.

Free skin cancer detection and prevention programs have been conducted throughout the United States. The New Jersey experience is outlined. Over 9,500 patients have been screened by a volunteer force of professionals. Patient education, an integral part of the program, stresses self-examination, recognition, and prevention of common cutaneous malignancies.

Humans

Tretinoin therapy for precancerous skin.

Although few actinic keratoses eventuate as squamous cell carcinomas, these precancerous lesions cannot be ignored. A medical regimen of topical tretinoin use and sun protection appears to be effective in treating and preventing these precancers, with the added cosmetic benefits of ameliorating the alterations which accompany sun damage on exposed skin.

Administration, Topical

Chronic arsenicism with vitiligo, hyperthyroidism, and cancer.

Chronic arsenicism, which may result from medicinal administration of arsenic, can present typical cutaneous signs, and is associated with an increase in cutaneous and internal malignancies. Recognition of the cutaneous premalignant stigmata of chronic arsenicism can identify a patient at risk, and promote early detection and treatment of life-threatening cancers.

Aged

Dysplastic nevi and melanoma.

Dysplastic nevi occur in individuals with an increased susceptibility to melanoma. Self-examination for new and changing lesions, avoidance of aggravating factors, and regular surveillance, permit early recognition, simple surgical excision, and cure of an otherwise fatal malignancy.

Dysplastic Nevus Syndrome

Variable expression in focal dermal hypoplasia. An example of differential X-chromosome inactivation.

We encountered three women from three generations of the same family with features of focal dermal hypoplasia (FDH). Two of the patients, the proposita and her mother, demonstrated severe manifestations, including skin, dental, skeletal, and visceral abnormalities. The proposita's grandmother, the first family member affected, had very mild expression, with aplasia cutis congenita and dental caries as the only features expressed. This family illustrates both the marked variability of expression and the proposed X-linked dominant mode of inheritance of FDH. We postulate that early embryologic random inactivation of the X chromosome bearing the mutant gene responsible for FDH is the cause of the variable expression.

Adolescent

Pectoralis muscle shortening and rigor development at different locations within the broiler breast.

Two experiments were conducted to evaluate differences in rigor development that occur as a function of location within the broiler breast muscles, pectoralis major (p. major) and pectoralis minor (p. minor). Three locations were evaluated, corresponding to anterior, middle, and posterior samples taken between the cranial and caudal ends of each muscle. Results of the first experiment indicated that the 1.55-mu sarcomere lengths of hot-boned p. major muscle at the anterior location were significantly shorter than those at the posterior location, which were 1.69 mu. Sarcomere lengths of p. minor were shorter than those of p. major in hot-boned muscles, but longer in those aged intact, indicating a significant muscle x treatment interaction. In the second experiment, the anterior location of hot-boned p. major reached the onset phase of rigor in about 1 h, whereas those at the posterior location required between 2 and 4 h postmortem. Between 1 and 8 h postmortem, sarcomere lengths for the anterior location of p. major were also significantly shorter than lengths in the posterior location, but the differences after 24 h were not significant. Samples at all locations of p. minor reached onset of rigor by 15 to 30 min postmortem, with no locational differences throughout the 24 h period of aging. The results of both experiments generally indicated differences between profiles of rigor development of the two muscles and between samples at different locations of the much larger and more complex p. major.

Animals