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W C Chen

Publications and source records attributed to W C Chen.

At least 55 records · Page 3Linked to original sources
PubMed2001

Synthesis and DNA nicking studies of a novel cyclic peptide: cyclo[Lys-Trp-Lys-Ahx-].

Two novel cyclic tetrapeptides: cyclo[Lys-Tyr-Lys-Ahx-] 7a and cyclo[Lys-Trp-Lys-Ahx-] 7b were synthesized by coupling protected amino acid in solution and the subsequent cyclization effected by the pentafluorophenyl ester method as described in previous papers. These cyclic peptides were designed and synthesized to study their interaction with DNA, based on previous reports that linear peptides Lys-Tyr-Lys and Lys-Trp-Lys could bind to various forms of DNA and cleaved supercoiled DNA at apurinic sites. Ethidium bromide displacement assay showed that the apparent DNA binding constant of linear Lys-Tyr-Lys and cyclic peptide 7a are far below 1 x 10(3) M(-1), whereas those of cyclic peptide 7b and linear Lys-Trp-Lys are 1.9 x 10(4) M(-1) and 9.5 x 10(3) M(-1), respectively. Kinetic studies using agarose gel electrophoresis showed that cyclic peptide 7b and Lys-Trp-Lys possessed DNA nicking activity on natural supercoiled phi X174 DNA with nicking rate of 50.7 and 75.6 pM min(-1) at 65 degrees C, respectively, whereas cyclic peptide 7a and linear Lys-Tyr-Lys were devoid of the corresponding activity. The DNA nicking rate increased significantly with increase in reaction temperature. At reaction temperatures lower than 65 degrees C, the DNA nicking rate of cyclic peptide 7b exceeded that of linear Lys-Trp-Lys. The addition of 1 microM ferrous ion did not give significant enhancement effect on the DNA nicking rate by the peptides. UV irradiation gave a marked rate enhancement on the DNA nicking rate of linear Lys-Trp-Lys and a moderate enhancement on the DNA nicking rate of cyclic peptide 7b.

DNA↗
PubMed2001

Nordihydroguaiaretic acid elevates osteoblastic intracellular Ca2+.

Nordihydroguaiaretic acid (NDGA) is widely used as a pharmacological tool to inhibit lipoxygenases; however, recent evidence suggests that it increases renal intracellular [Ca2+]i via novel mechanisms. Here the effect of NDGA on Ca2+ signaling in MG63 osteoblastic cells was explored using fura-2 as a Ca2+ indicator. NDGA (2-50 microM) increased [Ca2+]i in a concentration-dependent manner. The signal comprised an initial rise and an elevated phase over a time period of 4 min. Removing extracellular Ca2+ reduced 2-50 microM NDGA-induced signals by 62+/-2%. After incubation with 50 microM NDGA in Ca2+-free medium for several minutes, addition of 3 mM CaCl2 induced an increase in [Ca2+]i. NDGA (50 microM)-induced [Ca2+]i increases were not changed by pretreatment with 10 microM of verapamil, diltiazem, nifedipine, nimodipine and nicardipine. In Ca2+-free medium, pretreatment with the endoplasmic reticulum Ca2+ pump inhibitor thapsigargin (1 microM) inhibited 50 microM NDGA-induced [Ca2+]i increases by 69+/-3%. Inhibition of phospholipase C with 2 microM U73122 had little effect on 50 microM NDGA-induced Ca2+ release. Several other lipoxygenase inhibitors had no effect on basal [Ca2+]i. At a concentration that did not increase basal [Ca2+]i, NDGA (1 microM) did not alter 10 microM ATP- or 1 microM thapsigargin-induced [Ca2+]i increases. Alteration of protein kinase C activity with 1 nM phorbol 12-myristate 13-acetate or 2 microM GF 109203X did not affect 50 microM NDGA-induced [Ca2+]i increases. Together, the results show that NDGA increased [Ca2+]i in osteoblasts in a lipoxygenase-independent manner, by releasing stored Ca2+ in a fashion independent of phospholipase C activity, and by causing Ca2+ influx.

Calcium↗
PubMed2001

Paraneoplastic pemphigus in association with a retroperitoneal Castleman's disease presenting with a lichen planus pemphigoides-like eruption. A case report and review of literature.

A 50-year-old man presented with severe mucosal erosions of the lips, oral cavity and perianal area, a lichen planus-like eruption on the trunk and extremities and scaly plaques of the palms and soles. The clinical impression was of Stevens--Johnson syndrome, or paraneoplastic pemphigus (PNP). Histopathology revealed vacuolar interface and lichenoid dermatitis with dyskeratosis and suprabasal acantholytic vesiculation. Direct immunofluorescence showed deposition of IgG in the intercellular space and linear deposition of C3 along the basal membrane zone. Indirect immunofluorescence revealed circulating IgG with intercellular staining of the epithelium of rat urinary bladder. Western blotting demonstrated bands of 250- and 230-kDa antigens. The clinical, histological and immunological features were consistent with the lichen planus pemphigoides variant of PNP. A retroperitoneal hyaline-vascular Castleman's disease was detected and excised. The skin lesions worsened initially after tumour resection but improved gradually, leaving extensive melanosis after cyclosporin and mycophenolate mofetil treatment.

Castleman Disease↗
PubMed2001

Association of the vitamin D receptor gene start codon Fok I polymorphism with calcium oxalate stone disease.

OBJECTIVE: To assess the use of Fok I polymorphism (the most frequent polymorphism, at the start codon of the vitamin D receptor gene, VDR) as a convenient genetic marker in identifying the cause of urolithiasis. PATIENTS, SUBJECTS AND METHODS: A normal control group of 90 healthy subjects and 146 patients with calcium oxalate stones were examined. Using polymerase chain reaction (PCR)-based restriction analysis, the relationship between Fok I polymorphism and urolithiasis was evaluated. An unexcisable length of 265 bp was identified (allele CC) and two fragments (169 bp and 96 bp) identified as excisable lengths (allele TT). RESULTS: There was a statistically significant difference between the groups (chi-square test, P < 0.05) for the genotype of the VDR Fok I start codon polymorphism. The odds ratio (95% confidence interval) for the C allele in those at risk of stone disease was 1.672 (1.149-2.432). CONCLUSIONS: These results suggest that the VDR Fok I start codon polymorphism may be a good candidate for a genetic marker in calcium oxalate stone disease.

Adult↗
PubMed2001

The association of androgen- and oestrogen-receptor gene polymorphisms with urolithiasis in men.

OBJECTIVE: To evaluate the association of urolithiasis with polymorphic microsatellite (encoding cytosine, adenine, and guanine, CAG) repeats in the exon 1 region of the androgen receptor (AR) gene and thymine/adenine (TA) repeats in the oestrogen receptor (ER). PATIENTS AND METHODS: Patients with urolithiasis (149) and a group of normal controls (102) were examined and compared. The CAG repeats of the AR gene and TA repeats of the ER gene were detected by polymerase chain reaction. The CAG repeats ranged from 171 bp (10 CAG repeats with 141 bp of amplified flanking sequences) to 270 bp (43 CAG repeats). The TA repeats ranged from 160 bp to 194 bp. Associations between calcium oxalate stone disease and the CAG repeats in AR gene and TA repeats in ER gene were then evaluated. The results were classified according to sex and peaks in allelic frequency distribution. RESULTS: There was a significant difference between the male stone patients and the normal controls in the distribution of CAG repeats in the AR gene. Both groups showed a high percentage of 21-repeats in the allelic distribution, at 17 (16%) and 20 (37%) in stone patients and normal controls, respectively. The results indicate that 21-CAG repeats might be related to a lower risk of stone formation in men (P < 0.05). In the ER gene, the peak allelic distribution of TA repeats was 14, showing a significant difference between male stone patients and the normal control subjects (P < 0.01). There were no statistical differences between female stone patients and the control subjects in either the AR or the ER gene. CONCLUSION: Urolithiasis among men appears to be associated with AR gene CAG repeat and ER gene TA repeat polymorphisms, whereas there was no significant association among female stone patients. These sex hormone receptors seem to be related to the higher incidence of stone formation among men.

Adult↗
PubMed2001

Prevalence and significance of hepatitis B virus (HBV) pre-S mutants in serum and liver at different replicative stages of chronic HBV infection.

Several types of naturally occurring pre-S mutants in sera or liver tissues in patients with chronic hepatitis B virus (HBV) infection have been identified. To clarify the prevalence and significance of emergence of pre-S mutants, 140 sera and 18 resected livers from patients with HBV were studied. Replicative status was designated as high, intermediate, and low based on the HBV-DNA levels in serum or the expression of HBV antigens in liver. In vitro transfection and Western blot analysis were performed to characterize expression and secretion of HBsAg by the mutant constructs. Five major types (I to V) of pre-S deletion mutants in serum and liver and 2 types (VI and VII) in liver were identified. Pre-S mutant was 6.4% at high replicative phase, 13% at intermediate, and 37.5% at low or nonreplicative phases in serum. In livers, the same tendency existed: pre-S2 deletion mutants emerged and prevailed at a low replicative phase in hepatocytes that expressed a novel marginal pattern of HBsAg and usually clustered in groups. The deletion sequence of pre-S2 region coincides with human leukocyte antigen-restricted T- and B-cell epitopes. In vitro HBsAg was retained in the hepatocytes and synthesis and secretion of major surface antigen decreased for most of the pre-S mutants. Pre-S mutants prevailed with evolution of chronic HBV, probably under immune pressure. Emergence of pre-S mutants may account for the life-long persistence and discrepancy of HBsAg in serum and liver in HBV and may confer growth advantage in view of the clustering proliferation of hepatocytes harboring pre-S2 mutant.

Blotting, Western↗
PubMed2001

A new "sandwich" method of combined endoscopic variceal ligation and sclerotherapy versus ligation alone in the treatment of esophageal variceal bleeding: a randomized trial.

BACKGROUND: Variceal ligation is the optimum endoscopic method for treating esophageal variceal bleeding. However, both early and multiple recurrences of esophageal varices frequently follow ligation. The aim of this randomized study was to determine whether a new, combined endoscopic "sandwich" method (i.e., ligation-sclerotherapy-ligation) could achieve better results than ligation alone. METHODS: Ninety-four patients with cirrhosis and acute or recent esophageal variceal bleeding were randomized to undergo either the "sandwich" method or ligation alone (47 patients in each group). RESULTS: The sclerosant was retained in the varices for more than 30 minutes in 7 of 8 patients undergoing the "sandwich" method plus radiographic contrast medium. Active bleeding was controlled with this new method (9/9) as efficiently as ligation (12/12). The rate of recurrent bleeding was similar for both methods. Multivariate analysis showed the necessity for the use of antibiotics (odds ratio 3.95: 95% CI [1.60, 9.76]) to be an independent factor for recurrent bleeding. Two patients in the "sandwich" group developed strictures, but the frequency of other complications did not differ between the 2 groups. Kaplan-Meier analysis showed the cumulative probability of variceal recurrence was lower with the "sandwich" method (p = 0.0391). The survival rate and causes of death were similar in both groups. CONCLUSIONS: The "sandwich" method leads to longer retention of sclerosant in varices. This method is superior to ligation alone in terms of lower variceal recurrence rate and comparable to ligation with respect to hemostasis. However, it is unknown whether the lower recurrence rate of varices will persist long-term.

Combined Modality Therapy↗
PubMed2001

Feasibility and potential benefit of maintenance endoscopic variceal ligation in patients with unresectable hepatocellular carcinoma and acute esophageal variceal hemorrhage: a controlled trial.

BACKGROUND: Patients with unresectable hepatoma and acute esophageal variceal bleeding have extremely high rates of recurrent bleeding and mortality. This controlled study evaluates the feasibility and potential benefit of maintenance endoscopic variceal ligation in these patients. METHODS: Patients with unresectable hepatoma and acute esophageal variceal bleeding underwent emergent endoscopic variceal ligation. After hemostasis, patients were randomized to undergo maintenance or esophageal variceal ligation (EVL) as necessary (demand ligation). RESULTS: Fifty-four patients underwent maintenance EVL and 55 demanded EVL. One or more subsequent EVL session could be performed in only 30 patients (55.6%) in the maintenance group (actual maintenance ligation). Logistic regression analysis found that hepatic function determines the feasibility of maintenance ligation (Child-Pugh's A+B vs. C, OR 23.00: 95% CI [5.26, 100.66]). The survival and recurrent bleeding rates were similar in both groups. A subgroup analysis of patients with Child-Pugh's A and B hepatic reserve in both the maintenance EVL group (n = 24) and demand EVL group (n = 25) was performed to assess the potential benefit of maintenance ligation. Maintenance ligation reduced the rate of recurrent bleeding compared with demand ligation (p = 0.043). Cox regression showed that portal vein thrombosis and tumors in both hepatic lobes were also factors together with EVL that determined recurrence of bleeding. Survival was similar in both groups. CONCLUSIONS: Maintenance ligation is feasible in patients with unresectable hepatoma and variceal hemorrhage if they have a good hepatic reserve. Maintenance ligation might lower the rate of recurrent bleeding in this subgroup of patients.

Acute Disease↗
PubMed2001

Bacteremia after endoscopic injection of N-butyl-2-cyanoacrylate for gastric variceal bleeding.

BACKGROUND: Cyanoacrylate may form a barrier that prevents bacterial invasion when used in tissue. Because cyanoacrylate polymerizes within seconds on contact with aqueous media, it is used worldwide to arrest gastric variceal bleeding. The aim of this study was to determine the frequency of bacteremia after endoscopic cyanoacrylate injection for gastric variceal bleeding. METHODS: Patients with cirrhosis who underwent endoscopic cyanoacrylate injection for gastric variceal bleeding were included. Patients with cirrhosis who underwent upper endoscopy for nonvariceal upper GI bleeding were recruited as controls. Patients with infection before endoscopy were excluded. Blood was cultured in both groups. Injection needles and endoscope accessory channels were cultured in the cyanoacrylate injection group. RESULTS: More patients injected with cyanoacrylate had positive blood cultures in comparison with the control group (15/47 vs. 1/47, p < 0.0001). In the cyanoacrylate injection group, the volume of blood transfused and Child-Pugh score were factors associated with the occurrence of bacteremia. Most episodes of bacteremia were transient, except for 1 patient who died of sepsis. Most of the microorganisms cultured from blood samples were identical to those cultured from injection needles (65%) and accessory channels (90%). CONCLUSIONS: Endoscopic cyanoacrylate injection for gastric varices does not limit the spread of bacteria. The endoscope accessory channel was the major source of bacteria. Most episodes of bacteremia were transient and uneventful.

Bacteremia↗
PubMed2001

Effects of Tamm-Horsfall protein and albumin on calcium oxalate crystallization and importance of sialic acids.

BACKGROUND: Tamm-Horsfall protein and human serum albumin are common urinary proteins that show uncertain inhibitory action on the crystallization of calcium oxalate monohydrate. MATERIALS AND METHODS: Batch experiments on crystal nucleation, growth, and aggregation were performed using purified Tamm-Horsfall protein and albumin before and after enzymatic removal of sialic acids from the proteins. RESULTS: At a concentration of 100 nM, both Tamm-Horsfall protein and albumin promoted the time of crystal nucleation by 18.4% and 8.9%, respectively, relative to the control. However, both of the proteins exerted an inhibitory effect on crystal growth, with the IC(50) being 7.27 nM for Tamm-Horsfall protein and 37.5 nM for albumin. The inhibition of crystal aggregation was 81.82% by Tamm-Horsfall protein 100 nM but only 54.55% at 50 nM after enzymatic removal of the sialic acid. Instead of increasing the inhibition, the effect was changed to promotion after an increase in the concentration of Tamm-Horsfall protein to more than 500 nM for native protein and to more than 100 nM for the enzymatic digest. Albumin showed little change after enzymatic treatment and maintained a maximal inhibitory effect of 72.73% on crystal aggregation when the concentration reached to 100 nM. CONCLUSION: Because the promotion of nucleation could lessen the subsequent saturation of a calcium oxalate solution, it is concluded that Tamm-Horsfall protein and albumin show an overall effect of inhibition on crystallization in vitro. The inhibitory effect of Tamm-Horsfall protein is partly related to sialic acid.

Albumins↗
PubMed2001

No association of vitamin D receptor gene BsmI polymorphisms with calcium oxalate stone formation.

BACKGROUND AND PURPOSE: The formation of urinary stones is reported to be associated with the vitamin D receptor (VDR). As the most frequently seen polymorphism within the VDR gene is BsmI, it has been used as a genetic marker in searching for the cause of urolithiasis. We aimed to evaluate the association between calcium stone disease and the BsmI polymorphisms. MATERIALS AND METHODS: A control group of 90 healthy people and a group of 124 patients with calcium oxalate stones were examined. The polymorphism was detected using polymerase chain reaction (PCR)-based restriction analysis. A PCR product length was determined to be 580 bp (BB) whereas two fragments of 405 bp and 175 bp were determined to be excisable (bb) by BsmI endonuclease. Associations between calcium stone disease and BsmI polymorphisms were evaluated. RESULTS AND CONCLUSIONS: The results revealed no significant difference between normal individuals and stone patients (P = 0.891). The allelic distribution of B and b were similar within both the normal group and the stone patients. Therefore, the BsmI polymorphism of the VDR gene at intron 8 is not a suitable genetic marker for urinary stone disease.

Calcium Oxalate↗
PubMed2001

Chronic health risks from aggregate exposures to ionizing radiation and chemicals: scientific basis for an assessment framework.

Very little quantitative analysis is currently available on the cumulative effects of exposure to multiple hazardous agents that have either similar or different mechanisms of action. Over the past several years, efforts have been made to develop the methodologies for risk assessment of chemical mixtures, but mixed exposures to two or more dissimilar agents such as radiation and one or more chemical agents have not yet been addressed in any substantive way. This article reviews the current understanding of the health risks arising from mixed exposures to ionizing radiation and specific chemicals. Specifically discussed is how mixed radiation/chemical exposures, when evaluated in aggregation, were linked to chronic health endpoints such as cancer and intermediate health outcomes such as chromosomal aberrations. Also considered is the extent to which the current practices are consistent with the scientific understanding of the health risks associated with mixed-agent exposures. From this the discussion moves to the research needs for assessing the cumulative health risks from aggregate exposures to ionizing radiation and chemicals. The evaluation indicates that essentially no guidance has been provided for conducting risk assessment for two agents with different mechanisms of action (i.e., energy deposition from ionizing radiation versus DNA interactions with chemicals) but similar biological endpoints (i.e., chromosomal aberrations, mutations, and cancer). The literature review also reveals the problems caused by the absence of both the basic science and an appropriate evaluation framework for the combined effects of mixed-agent exposures. This makes it difficult to determine whether there is truly no interaction or somehow the interaction is masked by the scale of effect observation or inappropriate dose-response assumptions.

Animals↗
PubMed2001

Mechanism of bradykinin-induced Ca(2+) mobilization in MG63 human osteosarcoma cells.

BACKGROUND: The effect of bradykinin on intracellular free Ca(2+) levels ([Ca(2+)](i)) in MG63 human osteosarcoma cells was explored using fura-2 as a Ca(2+) dye. METHODS/RESULTS: Bradykinin (0.1 nM-1 microM) increased [Ca(2+)](i) in a concentration-dependent manner with an EC(50) value of 0.5 nM. The [Ca(2+)](i) signal comprised an initial peak and a fast decay which returned to baseline in 2 min. Extracellular Ca(2+) removal inhibited the peak [Ca(2+)](i )signals by 35 +/- 3%. Bradykinin (1 nM) failed to increase [Ca(2+)](i) in the absence of extracellular Ca(2+ )after cells were pretreated with thapsigargin (an endoplasmic reticulum Ca(2+) pump inhibitor; 1 microM). Bradykinin (1 nM)-induced intracellular Ca(2+) release was nearly abolished by inhibiting phospholipase C with 2 microM 1-(6-((17 beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122). The [Ca(2+)](i )increase induced by 1 nM bradykinin in Ca(2+)- free medium was abolished by 1 nM HOE 140 (a B2 bradykinin receptor antagonist) but was not altered by 100 nM Des-Arg-HOE 140 (a B1 bradykinin receptor antagonist). Pretreatment with 1 pM pertussis toxin for 5 h in Ca(2+) medium inhibited 30 +/- 3% of 1 nM bradykinin-induced peak [Ca(2+)](i) increase. CONCLUSIONS: Together, this study shows that bradykinin induced [Ca(2+)](i) increases in a concentration-dependent manner, by stimulating B2 bradykinin receptors leading to mobilization of Ca(2+) from the thapsigargin-sensitive stores in a manner dependent on inositol-1,4,5-trisphosphate, and also by inducing extracellular Ca(2+) influx. The bradykinin response was partly coupled to a pertussis toxin-sensitive G protein pathway.

Biological Transport↗
PubMed2001

Effects of Tamm-Horsfall protein and albumin on the inhibition of free radicals.

INTRODUCTION: Oxalate in urine can cause tubular cellular damage by the production of free radicals. Then, cell death and cellular debris may promote the retention of calcium oxalate crystals and finally the formation of stones. The two most abundant urinary proteins, Tamm-Horsfall protein (THP) and albumin, were tested for the effects of antioxidants. MATERIALS AND METHODS: By using xanthine-xanthine oxidase reaction, purified THP and albumin were tested for the inhibitory effect. OD(295) was used as a spectrophotometric method to measure the production of uric acid during the reaction. RESULTS AND CONCLUSIONS: Both proteins can inhibit the reaction of xanthine oxidase on xanthine, although the effect was decreased after enzymatic deglycosylation of sialic acid. Albumin has an IC(50) of 10.7 nM in native condition and 11.9 nM after deglycosylation, whereas THP has 69.6 nM in native condition and 102.0 nM in deglycosylated condition. The data indicates that THP and albumin have an antioxidant effect. Sialic acid in THP has partly an inhibitory effect and is associated with calcium oxalate formation. Studies have indicated that further investigation of the role of free radicals in the formation of urolithiasis and of sialic acid in protein function is needed.

Adjuvants, Immunologic↗
PubMed2001

Calcitonin receptor gene polymorphism: a possible genetic marker for patients with calcium oxalate stones.

OBJECTIVES: The formation of urinary stones is hypothesized to be associated with calcitonin receptors. The most commonly seen polymorphism is C/T at the 1377th nucleotide. Hence, these polymorphisms are being used as a genetic marker in the search for the cause of urolithiasis. METHODS: A normal control group of 105 healthy people and 102 patients with recurrent calcium oxalate stones were examined. The polymorphism was detected following a polymerase chain reaction-based and restriction analysis by AluI. An uncuttable length is 228 bp (CC) whereas two fragments of 120 and 108 bp are shown as cuttable lengths (TT). RESULTS: The results revealed significant differences between the normal individuals and the stone patients (p<0.01). The distribution of leucine (cuttable) homozygote in the stone group (2.0%) was higher than in the control group (0.0%). The odds ratio for the leucine allele of the calcitonin receptor gene in calcium oxalate stone disease is 5.634 (95% CI: 2.286--13.885). CONCLUSIONS: Results show that the polymorphism in the calcitonin receptor gene could be a genetic marker for urinary stone disease and therefore it is worthwhile pursuing further studies of the leucine allele of calcitonin receptor gene due to it is strongly correlated with stone disease.

Adult↗
PubMed2001

Development and validation of growth model for Yersinia enterocolitica in cooked chicken meats packaged under various atmosphere packaging and stored at different temperatures.

Mathematical models that can predict the growth of Yersinia enterocolitica in chicken meats were evaluated in this study. The growth curves for Y. enterocolitica in chicken meats variously packaged (air, vacuum, and modified atmosphere packaging [MAP]) and stored at various temperatures (4, 10, 16, 22, 28, and 34 degrees C) were constructed. The Gompertz model was applied to fit each of the experimental curves for the conditions mentioned above. The variations in the parameters, including lag time (lambda) and specific growth rate (mu), at various temperatures were then described by the following models: the variations in lag time were described by the Adair and Smith models and the variations in the specific growth rate were described by the Ratkowsky and Zwietering models. The various models were then compared using graphical and mathematical analyses such as mean square error (MSE), regression coefficient (r2), bias factor, and accuracy factor. The results indicate that the mean r values in the Gompertz model for chicken meats packaged in air, vacuum, and MAP were 0.99, 0.99, and 0.95, respectively. The lag time modeled with the Adair and Smith functions exhibited a greater variance and demonstrated larger errors. The MSEs were 0.0015 and 0.0017 for Ratkowsky and Zwietering models, respectively. The r2 values in the Ratkowsky and Zwietering models were both 0.99. The bias factor was 1.017 for the Ratkowsky model and 1.096 for the Zwietering model. The accuracy factor of the Zwietering model was 1.174, which was lower than that in the Ratkowsky model (1.275), indicating that the former model was more accurate than the latter in predicting the specific growth rate of Y. enterocolitica in chicken meats.

Animals↗