Combined effects of sous-vide cooking conditions on meat and sensory quality characteristics of chicken breast meat

This study investigated the combined effects of cooking temperature and time on the meat and eating quality characteristics of the sous-vide chicken breast. For the control group, chicken breast samples were cooked in a convection oven until the internal temperature reached 71°C. Each sample for sous-vide cooking was vacuum packaged and then cooked under continuous thermocontrolled conditions in a water bath at 6 combinations of cooking temperature (60 and 70°C) and time (1, 2, and 3 h). Sous-vide cooked chicken meat at 60°C for 1 h (SV60-1h) showed lower cooking loss (6.58 vs. 26.5%, P < 0.05), Warner-Bratzler shear force (21.7 vs. 29.1 N, P < 0.05), and hardness (9.40 vs. 17.3 N, P < 0.05) than meat cooked by conventional oven. Similar to the objective tenderness parameters, cooked chicken meat from the SV60 treatments for all cooking times showed higher scores in all the tenderness attributes than the control group (P < 0.05). However, a higher flavor intensity was observed in the SV70-3h and control groups than in the SV60 treatments (P < 0.05). Owing to a lesser developed flavor in chicken meat from the SV60-1h treatment, the SV60-2h and 3h treatments were assigned a higher acceptability rating for overall impression (P < 0.05). Therefore, cooking temperature and time of sous-vide significantly influenced the physicochemical and palatability characteristics of chicken breast. In this study, the optimum conditions for the sous-vide chicken breast are to continuously cook at 60°C for 2 to 3 h to improve sensory quality characteristics without reducing the water-holding capacity.

Sun heated surfaces are an environmental hazard for young children

AIMS

Children commonly sustain heat contact type burn injuries from sun heated surfaces during the summer months in hot, sunny climates. The aim of this study was to review the causes and outcomes in a series of heat contact type burns sustained by children who touched hot sun heated surfaces.

METHODS

A retrospective chart review was performed to identify all children who sustained burn injuries due to naturally heated surfaces and were treated between January 2012 and December 2017 at Children's Hospital Colorado. Demographics of the subjects and clinical data regarding their burn injuries were collected.

RESULTS

A total of 58 children were identified over the study period, involving 118 burn wounds. The median age was 17 months (interquartile range = 14-23), and 33 were male (57%). Mean total body surface area (TBSA) was 1.4% (standard deviation = 1). A foot was the most commonly involved area, affecting 36 subjects (62%). The most common causes of these burn injuries were metal thresholds (n = 7, 12%) and metal covers or lids (n = 5, 9%) outside the home. The depth of the burn injury was partial thickness in 57 children (98%). The mean time to heal was 12 ± 6 days, and the majority of injuries occurred in June (n = 28, 48%).

CONCLUSION

Heat contact type burn injuries from sun heated surfaces commonly affect children ⩽2 years of age during the summer months, and the majority of these injuries occur around the home environment. They are preventable injuries, and this information should be used for prevention and education materials for parents and healthcare providers, who reside in hot, sunny climates.

Comparison of marbling fleck characteristics between beef marbling grades and its effect on sensory quality characteristics in high-marbled Hanwoo steer

The aim of this study was to compare the intramuscular fat (IMF) content and marbling fleck characteristics measured by computerized image analysis among the eight grades of Korean beef marbling standard (BMS). Additionally, this study examined the effects of the marbling fleck characteristics on objective tenderness parameters and sensory quality characteristics in high-marbled Hanwoo steers (BMS grades 7 to 9). Marked differences were observed in marbling fleck characteristics among the BMS grades (P < .05), whereas the coarseness was similar in high-marbled beef (P > .05). Due to a greater extent of coarse marbling fleck, coarse marbled steaks from high-marbled cattle were assigned higher scores of tenderness attributes, including softness, initial tenderness, and chewiness, as well as mouth coating, but were assigned lower acceptability ratings for IMF content and overall impression compared to fine marbled steaks (P < .05). Taken together, considering the marbling fleck traits can be an effective tool for improving the accuracy of beef grading systems.

Polycystic ovary syndrome with hyperandrogenism as a risk factor for non-obese non-alcoholic fatty liver disease

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is known to be associated with polycystic ovary syndrome (PCOS). However, most studies investigated the prevalence of NAFLD in obese PCOS patients.

AIM

To compare the prevalence of non-obese NAFLD in women with or without PCOS, and to assess an independent association between PCOS and NAFLD in a non-obese Asian cohort.

METHODS

This was a case-control study using a prospective PCOS cohort. After subjects with other potential causes of chronic liver disease were excluded, 275 non-obese women with PCOS and 892 non-obese controls were enrolled. NAFLD was determined by hepatic ultrasonography. Main outcomes were the prevalence of NAFLD on hepatic ultrasonography between non-obese women with or without PCOS, and an independent association between non-obese NAFLD and PCOS.

RESULTS

Non-obese women with PCOS had a significantly higher prevalence of NAFLD than those without PCOS (5.5% vs. 2.8%, P = 0.027). PCOS was associated with non-obese NAFLD (odds ratio: 2.62, 95% confidence intervals: 1.25-5.48) after adjustment for age and body mass index (BMI). In women with PCOS, the level of androgenicity represented by free testosterone or free androgen index was associated with NAFLD after adjustment for age, BMI, lipid profile, insulin resistance or glycaemic status.

CONCLUSIONS

Non-obese NAFLD is more prevalent in women with polycystic ovary syndrome than in those without. In non-obese patients with polycystic ovary syndrome, hyperandrogenemia may be an independent risk factor for non-obese NAFLD.

DBC2/RhoBTB2 functions as a tumor suppressor protein via Musashi-2 ubiquitination in breast cancer

The gene encoding ‘deleted in breast cancer 2' (DBC2), also referred to as RHOBTB2 (Rho-related BTB domain-containing protein 2), is classified as a tumor suppressor gene. DBC2 is a substrate-specific adaptor protein for a novel class of Cullin-3 (CUL3)-based E3 ubiquitin ligases; however, it is unclear if the substrate adaptor function of DBC2 is required for its tumor suppressor activity. Furthermore, the key substrates of DBC2-mediated ubiquitination have yet to be identified. In the present study, we established a genome-wide human cDNA library-based in vitro ubiquitination target screening assay and identified Musashi-2 (MSI2) as a novel ubiquitination target protein of DBC2. MSI2 directly interacted with DBC2, and this interaction promoted MSI2 polyubiquitination and proteasomal degradation in breast cancer cells. Overexpression and knockdown experiments demonstrated that DBC2 suppressed MSI2-associated oncogenic functions and induced apoptosis. Immunohistochemistry analysis of a breast cancer tissue microarray revealed that DBC2 and MSI2 protein levels are inversely correlated in both normal breast tissues and breast cancer tissues. Taken together, these findings provide evidence that DBC2 suppresses tumorigenesis in breast cancer by ubiquitinating MSI2.

Comparison of Muscle Fiber and Meat Quality Characteristics in Different Japanese Quail Lines

The aim of this study was to compare the growth performance, fiber characteristics of the pectoralis major muscle, and meat quality characteristics in the heavy weight (HW) and random bred control (RBC) quail lines and genders. The HW male exhibited more than two times greater body (245.7 vs 96.1 g, p<0.05) and pectoralis major muscle (PMW; 37.1 vs 11.1 g, p<0.05) weights compared to the RBC female. This growth performance in the HW line was associated with a greater muscle fiber area (1,502 vs 663.0 μm², p<0.001) compared to the RBC line. Greater muscle mass of the HW male was accompanied by a higher percentage of type IIB fiber compared to the HW female (64.0% vs 51.0%, p<0.05). However, muscle fiber hyperplasia (increase in fiber number) has had a somewhat limited effect on PMW between the two lines. On the other hand, the HW line harboring a higher proportion of type IIB fiber showed rapid pH decline at the early postmortem period (6.23 vs 6.41, p<0.05) and lighter meat surface (53.5 vs 47.3, p<0.05) compared to the RBC line harboring a lower proportion of type IIB fiber. There were no significant differences observed in the measurement of water-holding capacity including drip loss (2.74% vs 3.07%, p>0.05) and cooking loss (21.9% vs 20.4%, p>0.05) between the HW and RBC lines. Therefore, the HW quail line developed by selection from the RBC quail, was slightly different in the meat quality characteristics compared to the RBC line, and a marked difference was found in growth performance between the two quail lines.

MicroRNA Profile of Granulosa Cells after Ovarian Stimulation Differs According to Maturity of Retrieved Oocytes

Background: Recent animal studies demonstrated that regulating the microRNA (miRNA) in granulosa cells (GCs) modulates the meiotic competence of oocytes. However, the difference in expression profiles of miRNAs in human GCs according to the maturity of the oocyte still remains to be elucidated. Objective: This observational study investigated whether the miRNA profile of human GCs differs according to the maturity of the retrieved oocyte after controlled ovarian stimulation for in vitro fertilization (IVF). Methods: Ten women who underwent ovarian stimulation cycles with GnRH agonist long protocols were recruited. The follicular fluid (FF) from dominant follicles was individually aspirated at oocyte retrieval. Oocytes were divided into two groups according to oocyte maturity ("mature group" vs. "immature group"). GCs were collected from the FF and miRNA was analyzed using real-time PCR. Results: Mean number of MII oocytes in the mature group was 1.6 ± 0.9 with none in the immature group (p = 0.008). Mean number of MI oocytes was 5.6 ± 2.1 in the mature group and 1.0 ± 0.0 in the immature group (p = 0.008). The total number of retrieved oocytes was 8.8 ± 1.9 in the mature group and 2.0 ± 1.2 in the immature group (p = 0.008). The GCs of the mature group showed a significantly lower expression of hsa-let-7b compared to the GCs of the immature group (p < 0.001). Conclusion: Taken together, the miRNA expression profiles of human GCs obtained from dominant follicles are associated with maturity of the adjacent oocyte and may be useful as a prognosticator of IVF outcome.

Effects of Anesthetic Agent Propofol on Postoperative Sex Hormone Levels

Introduction: Several studies have found anesthetic agents including propofol in ovarian follicular fluid. However, little is known about the effect of anesthetic agents on ovarian function. We aimed to investigate whether there were differences in the postoperative levels of sex hormones when propofol was used as the anesthetic agent. Methods: A retrospective review was done of 80 patients who underwent ovarian surgery, with 72 infertile women serving as controls. Patients were included in the study if their serum estradiol (E2) and follicle stimulating hormone (FSH) levels were measured during their first postoperative menstrual cycle. Results: Patients were grouped according to the use or non-use of propofol as follows: propofol group (n = 39) and non-propofol group (n = 41). The control group did not undergo surgery. Postoperative E2 levels did not differ between the three groups, but FSH levels were significantly higher in the patients who had undergone surgery compared to controls (p < 0.05). Post-hoc analysis of E2 and FSH levels in the propofol and non-propofol groups did not show any significant differences. Conclusions: The use of propofol did not result in any differences compared to other anesthetic agents in terms of postoperative sex hormone levels after gynecologic surgery. The type of anesthetic agent does not seem to affect the postoperative levels of female sex hormones.

Mild heat stress enhances differentiation and proliferation of Japanese quail myoblasts and enhances slow muscle fiber characteristics

The objective of this study was to investigate the effect of mild heat stress on muscle fiber hyperplastic and hypertrophic growth in quail primary myogenic cells to better understand the mechanisms leading to increased skeletal muscle development in avian embryos incubated at a higher temperature. Compared to control cultures maintained at 37°C, incubation at 39°C enhanced myotube length (P < 0.01) and diameter (P < 0.001) at 3 days after differentiation (D3). This enlargement of the myotubes incubated at 39°C can be explained by differences in the fusion index (56.7 vs. 46.2%, P < 0.05) and nuclei number per myotube (18.1 vs. 10.8, P < 0.001) compared to the control cells at D3. Additionally, a higher density of myotubes at D3 in cultures exposed to a higher temperature were related to higher levels of Pax-7 (P < 0.05) compared to the control cells incubated continuously at 37°C. These results indicated a higher proliferative capacity in cells exposed to mild heat stress compared to the control cells. On the other hand, mild heat stress enhanced protein levels of slow myosin heavy chain isoform (P < 0.01) and cytochrome c oxidase subunit IV (P < 0.01) compared to the control cells at D3. These discrepancies in protein expression indicated maintenance of slow muscle fiber type characteristics in myotubes incubated at 39°C. Our results suggest that mild heat stress plays a significant role in myogenic mechanisms related to muscle mass and development.

Estimation of pork quality traits using exsanguination blood and postmortem muscle metabolites

The current study was designed to estimate the pork quality traits using metabolites from exsanguination blood and postmortem muscle simultaneously under the Korean standard pre- and post-slaughter conditions. A total of 111 Yorkshire (pure breed and castrated male) pigs were evaluated under the Korean standard conditions. Measurements were taken of the levels of blood glucose and lactate at exsanguination, and muscle glycogen and lactate content at 45 min and 24 h postmortem. Certain pork quality traits were also evaluated. Correlation analysis and multiple regression analysis including stepwise regression were performed. Exsanguination blood glucose and lactate levels were positively correlated with each other, negatively related to postmortem muscle glycogen content and positively associated with postmortem muscle lactate content. A rapid and extended postmortem glycolysis was associated with high levels of blood glucose and lactate, with high muscle lactate content, and with low muscle glycogen content during postmortem. In addition, these were also correlated with paler meat color and reduced water holding capacity. The results of multiple regression analyses also showed that metabolites in exsanguination blood and postmortem muscle explained variations in pork quality traits. Especially, levels of blood glucose and lactate and content of muscle glycogen at early postmortem were significantly associated with an elevated early glycolytic rate. Furthermore, muscle lactate content at 24 h postmortem alone accounted for a considerable portion of the variation in pork quality traits. Based on these results, the current study confirmed that the main factor influencing pork quality traits is the ultimate lactate content in muscle via postmortem glycolysis, and that levels of blood glucose and lactate at exsanguination and contents of muscle glycogen and lactate at postmortem can explain a large portion of the variation in pork quality even under the standard slaughter conditions.

Effects of muscle cortisol concentration on muscle fiber characteristics, pork quality, and sensory quality of cooked pork

The effect of muscle cortisol concentration on muscle fiber characteristics and technological and sensory quality of pork was investigated. With the exception of the percentage of type IIA fibers, muscle fiber characteristics were not associated to cortisol levels. However, muscle cortisol concentration was positively associated with muscle pH(24h) (r = 0.23, P<0.05) and negatively associated with drip loss (r = -0.49, P<0.001), lightness (r = -0.24, P<0.05), shear force (r = -0.25, P<0.05), and texture profile analysis-hardness (r = -0.35, P<0.01). Additionally, the water-holding capacity of meat samples was affected by cortisol levels, with lower cortisol concentrations associated with less tender samples. These results indicate that the concentration of cortisol in the muscle is related with meat quality as well as the sensory quality of cooked pork.

The influence of pork quality traits and muscle fiber characteristics on the eating quality of pork from various breeds

The purpose of this study was to compare parameters associated with pork quality, muscle fiber, and eating quality among various breeds, and to examine if differences in eating quality were associated to pork quality and muscle fiber characteristics. For carcass and pork quality, although there were significant differences among breeds, the values of parameters in all pigs were assigned a normal quality class, a likely outcome of the similarity in the area percentage of type I and IIB fibers. For eating quality, pork loins from Berkshire pigs were more tender and full of pork flavor than Landrace and Yorkshire pigs. Except juiciness and mouth coating, over 20% of the variability in the eating quality parameters can be explained by pork quality traits and muscle fiber characteristics using multiple regression analysis. Furthermore, differences in muscle pH(24h), cooking loss, shear force, and NPPC marbling score could explain a large proportion of variation in eating quality parameters associated with the texture of pork.

Practical use of surimi-like material made from porcine longissimus dorsi muscle for the production of low-fat pork patties

This study evaluates the effect of replacing fat with surimi-like material (SLM) made from the porcine longissimus dorsi muscle on the physicochemical and sensory characteristics of pork patties. Pork patties were produced with different levels of fat and SLM using a commercial method. Pork patties produced with 20% SLM had the lowest fat content (1.76%, P<0.001), and had a higher cooking yield (87.41 vs. 78.57%, P<0.05) and less shrinkage (4.01 vs. 9.02%, P<0.001) than patties produced with 20% back-fat (control). Moreover, patties produced with SLM exhibited more acceptable organoleptic characteristics, including tenderness (P<0.01) and overall acceptability (P<0.001), than full-fat control patties. These results indicated that SLM cannot only be used as a fat replacer, but that it also improves the physicochemical and sensory characteristics of low-fat pork patties.

Association of the interferon-γ gene (CA)n repeat polymorphism with endometriosis

OBJECTIVE

To investigate whether the interferon-γ (IFN-γ) gene (CA)(n) repeat polymorphism is associated with susceptibility to endometriosis.

DESIGN

Case-control study.

SETTING

University Department of Obstetrics and Gynaecology.

POPULATION

Women with (n = 622) and without (n = 442) endometriosis.

METHODS

Genotyping was performed by fluorescent polymerase chain reaction (PCR) and gene-scan analysis.

MAIN OUTCOME MEASURES

Genotype distribution and allele frequency of the dinucleotide (CA)(n) repeat polymorphism in the IFN-γ gene.

RESULTS

Seven alleles (12-18 repeats) of the IFN-γ gene (CA)(n) repeat polymorphism were found. In both patients with endometriosis and controls the most common allele was composed of 13 repeats, followed by an allele of 15 repeats, and then by an allele of 12 repeats. Patients with endometriosis had a significantly higher incidence of genotypes with alleles composed of fewer repeats (12-13 repeats), compared with the controls (92.0 versus 84.4%, respectively, P < 001).

CONCLUSIONS

Our results suggest that the (CA)(n) repeat polymorphism in the IFN-γ gene may be associated with a risk of endometriosis in the South Korean population.

Correlations of trained panel sensory values of cooked pork with fatty acid composition, muscle fiber type, and pork quality characteristics in Berkshire pigs

The objective was to examine the relationship of trained panel sensory scores of cooked pork with fatty acid composition, muscle fiber type, and meat quality characteristics from Berkshire pigs. No or few associations were found between the panel sensory scores of cooked meat, especially tenderness attributes, and fatty acid composition; however, intramuscular fat content positively correlated with off-flavor score (r=0.31). On the other hand, the morphological characteristics of muscle fibers were correlated with panel sensory values. Muscles with smaller cross-sectional area and higher density of fibers were more closely associated with softer, more tender panel scores and a lower number of chews than muscles with larger fiber area and lower density of fibers. The water holding capacity test of filter-paper fluid uptake was moderately correlated with panel scores of softness (r=0.33), initial tenderness (r=0.38), chewiness (r=0.40), juiciness (r=-0.27), flavor intensity (r=-0.23), and off-flavor (r=0.30). Panel sensory values of Berkshire pig meat was moderately related to postmortem meat quality, especially water holding capacity. A more thorough understanding of the relationships between fatty acid composition and muscle fiber type with palatability is needed.

The effects of hormone therapy on metabolic risk factors in postmenopausal Korean women

OBJECTIVE

We sought to assess the prevalence of metabolic syndrome (MetS) among Korean postmenopausal women and to investigate the effect of hormone therapy status and reproductive characteristics on body composition and MetS risk factors.

STUDY DESIGN

We performed a cross-sectional study involving a cohort of 2005 postmenopausal Korean women. We defined MetS using the modified National Cholesterol Education Program (NCEP) criteria proposed by the American Heart Association/National Heart, Lung, and Blood Institute guidelines. The criteria for abdominal obesity were adopted from the cut-offs suggested by the Korean Society for the Study of Obesity. Participants with three or more of the following conditions were classified as having MetS: waist circumference ≥ 85 cm; blood pressure ≥ 130/85 mmHg; fasting plasma triglycerides ≥ 150 mg/dl; high density lipoprotein cholesterol < 50 mg/dl; glucose ≥ 100 mg/dl and/or receiving treatment for their condition.

RESULTS

The prevalence of MetS was 22.1% in the study population and increased with age. After adjusting for age and related reproductive characteristics, it was found that ever-use of hormone therapy (prior or current) was associated with decreased risk of postmenopausal MetS. Among individual risk factors for MetS, current hormone therapy seemed to be associated with decreased prevalence of abdominal obesity and better glucose metabolism and prior use of hormone therapy were associated with lower risk of abdominal obesity and high blood pressure.

CONCLUSION

Postmenopausal hormone therapy is associated with decreased risk of MetS in postmenopausal Korean women.

Finding ancient parasite larvae in a sample from a male living in late 17th century Korea

Parasitological examination of samples from tombs of the Korean Joseon Dynasty (1392-1910) could be helpful to researchers in understanding parasitic infection prevalence in pre-industrial Korean society. Whereas most of our previous parasitological studies revealed the presence of ancient parasite eggs in coprolites of Korean mummies, a sample from a man living in late 17th century Korea proved to be relatively unique in possessing what appeared to be several species of parasite larvae. The larvae identified included Strongyloides stercoralis and Trichostrongylus spp., along with eggs of Ascaris lumbricoides, Trichuris trichiura, and Paragonimus westermani. Since ancient parasite larvae retain enough morphology to make proper species identification possible, even after long burial times, the examination of parasite larvae within ancient samples will be conducted more carefully in our future work.

Potential use of supercritical carbon dioxide to decontaminate Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella typhimurium in alfalfa sprouted seeds

We sought to develop a method of decontaminating alfalfa sprouts of Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella typhimurium without altering the seed germination capability using supercritical carbon dioxide (SC-CO(2)). Samples were treated with SC-CO(2) at 10, 15, or 20 MPa and temperatures of 35, 40, or 45 degrees C for 5, 10, or 15 min. The germination percentage was measured after three days of germination. Generally, treating seeds with SC-CO(2) at higher pressures, temperatures, or for longer treatment times resulted in greater microbial reductions than treatments at lower pressures, temperatures, or for shorter treatment times. SC-CO(2) treatment clearly reduced the microorganism levels in alfalfa seeds; in particular, treatment at 20 MPa and 45 degrees C for 15 min reduced levels of the three pathogens by >7.0 log colony forming units (CFU)/g. However, SC-CO(2) treatment at a high pressure and high temperature, especially treatment at 20 MPa and 40 or 45 degrees C, impaired the seed germination capability in some cases. Without impairing the germination capability, the maximum reduction level of E. coli O157:H7 was 3.51 CFU/g with SC-CO(2) treatment at 15 MPa and 35 degrees C for 10 min. Maximum reductions of L. monocytogenes and S. typhimurium were 2.65 and 2.48 log CFU/g, respectively, with treatment at 10 MPa and 45 degrees C for 5 min. Therefore, our results indicate that SC-CO(2) treatment can be used to effectively improve alfalfa seed safety.

Sensory evaluations of porcine longissimus dorsi muscle: Relationships with postmortem meat quality traits and muscle fiber characteristics

The objective of this study was to investigate sensory evaluations and their relationships with meat quality measurements and histochemical characteristics in both fresh and cooked pork. Based on the results, postmortem meat quality traits were closely related to almost all the evaluated sensory attributes. With regard to histochemical characteristics, muscle fiber area was related to both fresh- (r=0.18, P<0.05) and cooked-meat color (r=-0.24, P<0.01) as well as abnormal flavor intensity (r=0.25, P<0.01), and muscle fiber composition was associated with fresh pork color and taste acceptability after cooking. There were no significant relationships (P>0.05) between type IIa muscle fiber content and the evaluated sensory attributes; however, good meat sensory quality was partially explained by the percentage of type I fiber.

The relation of blood glucose level to muscle fiber characteristics and pork quality traits

The purpose of this study was to examine the relationships between blood glucose level, muscle fiber characteristics, and pork quality. Muscle samples were classified into three groups based on blood glucose level measured at slaughter. Pigs with higher area percentages of fiber type IIB showed higher blood glucose levels compared to pigs with lower area percentages of fiber type IIB. The high blood glucose level group presented lower pH values at 45min and 24h postmortem, and also had higher L(∗) values and reduced water holding capacity. In addition, blood glucose level had a negative relationship with pH(45min) and the solubility of sarcoplasmic and myofibrillar proteins, whereas it had a positive relationship with drip loss and filter-paper fluid uptake. In conclusion, blood glucose level was related to muscle fiber area composition and could partially indicate ultimate pork quality.

Modulation of firing activity by ATP in dopamine neurons of the rat substantia nigra pars compacta

ATP acts as a neurotransmitter or co-neurotransmitter in many areas of the CNS and peripheral nervous systems; however, little is known about the expression and functional role of purinoceptors (P2) in midbrain dopaminergic neurons. Therefore, we investigated P2X receptor expression and regulation of spontaneous firing activity in dopaminergic neurons of the substantia nigra pars compacta (SNc) in rats using patch-clamp and Ca(2+)-imaging techniques. In most neurons, application of ATP (1 microM-1 mM) increased firing rate dose-dependently (EC(50)=1.26+/-0.26 microM, n=45). When the P2-receptor agonists such as 2-methylthio-adenosine 5'-triphosphate (2-MeSATP) or ATPgammaS were applied or pressure-applied to the neuron, the firing activity increased together with a rise in cytosolic Ca(2+) concentration ([Ca(2+)]c), but application of beta,gamma-methylene ATP (P2X(1, 3) agonist) or methylthio-adenosine 5'-diphosphate (P2Y(1) agonist) had no effect. In many neurons, the effect of ATP was abolished by the application of the P2-receptor antagonists, suramin or pyridoxal-phosphate-6-azophenyl-2',4'-disulfonic acid (PPADS). When ATP was applied in a Ca(2+)-free solution, there was no detectable change in [Ca(2+)]c, suggesting that ATP does not release Ca(2+) from intracellular stores. In the single-cell reverse transcription polymerase chain reaction (RT-PCR), we found that 65% of dopaminergic neurons expressed mRNAs for P2X receptors; positive amplifications of P2X(6) (57.1%), P2X(2/6) (25.0%), and P2X(4) mRNA (17.9%), respectively. From the above results, we could conclude that ATP modulates firing activities in the rat SNc dopaminergic neurons, possibly via P2X(2), P2X(2/6), and/or P2X(4) receptors.

The relation between glycogen, lactate content and muscle fiber type composition, and their influence on postmortem glycolytic rate and pork quality

This study examined the relation between glycogen, lactate content and muscle fiber type composition, and evaluated their influence on postmortem glycolytic rate and meat quality. Muscle samples were classified based on their glycogen and lactate content at 45min postmortem. Muscles with low glycogen and high lactate levels showed low muscle pH(45min) and high R-values. However, muscles with low glycogen and lactate levels showed normal rates of postmortem glycolysis and normal meat quality. On the other hand, muscles with high glycogen and lactate content showed rapid postmortem glycolysis, paler surface color, higher drip loss, and higher extents of protein denaturation than muscles with high glycogen and low lactate content. These results may be partially explained by muscle fiber type composition. Muscles with low glycogen and lactate content at early postmortem are composed of significantly higher fiber type I and lower fiber type IIB as compared to muscles with high glycogen and lactate content.

Examining ethnic differences for bevacizumab-induced hypertension and proteinuria

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Background: Bevacizumab is an increasingly used anti-cancer treatment with common side effects including hypertension (htn) and proteinuria which occur in approximately 10% and 20% of the patients, respectively. Little is known regarding ethnic variations of bevacizumab induced htn and proteinuria, particularly in African-Americans (AA) who have a high prevalence of htn and susceptibility to kidney disease. Methods: We conducted a retrospective chart review of patients who completed bevacizumab alone or as a chemotherapy regimen at the University of Illinois at Chicago for an 18-month study period. We collected blood pressure (BP) measurements and urinanalyses before starting bevacizumab, during bevacizumab and after stopping bevacizumab, in addition to concurrent medications, past medical history and demographics. Htn and proteinuria were graded by CTC v3.0. Patients with less than two successive doses of bevacizumab or unreliable ethnicity were excluded. Results: 27 subjects were eligible. Eighteen AA (67%) and 9 (33%) non-AA were included. Twenty-two (81%) had colorectal cancer. AA received a median of 10 cycles and non-AA received a median of 6 cycles. Six subjects (22%) developed any grade htn toxicity; maximum grade: grade 2=4 (15%), grade 3=2 (7%). Htn toxicity occurred in 28% AA and 11% non-AA (p=NS). Previous history of hypertension was found in 15 subjects (55%): AA=14 vs. non-AA=1 (p=0.002) and was not correlated with hypertensive toxicity. Twelve subjects (44%) developed any grade proteinuria; maximum grade: grade 1=9 (33%), grade 2=3 (11%). Proteinuria toxicity occurred in 50% AA and 33% non-AA (p=NS). Presence of hypertensive toxicity was associated with increased risk of proteinuria. Clinical benefit (PR, SD) was seen in 15 subjects (55%). Rate of clinical benefit was 67% in AA and 33% in non-AA (p=NS). Clinical benefit did not correlate with hypertensive or proteinuria toxicities. Conclusions: AA were more prone than non-AA to bevacizumab induced hypertension and proteinuria toxicity in this retrospective study. Higher clinical benefit was seen in AA.

No significant financial relationships to disclose.

FK506 increases pigmentation and migration of human melanocytes

BACKGROUND

Topical tacrolimus (FK506) is a potential therapeutic option for vitiligo management. Despite its clinical efficacy, the underlying mechanism of how topical tacrolimus induces repigmentation in vitiligo has scarcely been investigated.

OBJECTIVES

To investigate the direct effects of FK506 on pigmentation and migration of human melanocytes.

METHODS

Cell proliferation was measured using a Coulter counter. The effects on pigmentation were investigated by measuring melanin contents, tyrosinase activity and tyrosinase expression. To determine the effects of FK506 on cell migration, we performed scratch assays and Boyden chamber assays.

RESULTS

FK506 treatment increased melanin contents, although there was an inhibitory effect on growth of melanocytes. The increase of pigmentation was due to the result of the stimulatory action of FK506 on tyrosinase activity and its expression, which eventually led to melanin biosynthesis. Furthermore, cell migration was enhanced by FK506 treatment.

CONCLUSIONS

These findings provide in vitro evidence demonstrating direct effects of FK506 on pigmentation and melanocyte migration and may provide a possible mechanism for the effect of tacrolimus in vitiligo.

Increased telomerase activity and human telomerase reverse transcriptase mRNA expression in the endometrium of patients with endometriosis

BACKGROUND

Endometriosis is considered a frequent, benign disease with the ability to undergo neoplastic processes. The aim of this study was to evaluate the limitless replication potential of the endometrium in patients with endometriosis by examining human telomerase reverse transcriptase (hTERT) mRNA expression and telomerase activity.

METHODS

Endometrium samples from 30 endometriosis patients and 30 patients without endometriosis were obtained via endometrial biopsy. The expression of hTERT mRNA was determined by real-time RT-PCR assay, and telomerase activity was measured by telomerase repeat amplification protocol (TRAP) assay.

RESULTS

The mean normalized hTERT (N hTERT) mRNA level was significantly higher in the endometriosis than in the control group (P = 0.013). The mean hTERT mRNA levels during the proliferative phase and during the secretory phase were higher in the endometriosis group than in the control group, although the difference was only significant for the secretory phase (P = 0.036). We found a prominent difference in endometrial telomerase activity between moderate-to-severe endometriosis and the control group (P = 0.048). The levels of hTERT mRNA and telomerase activity increased as the disease became more severe (P = 0.038, P = 0.016).

CONCLUSIONS

This study showed the overexpression of hTERT mRNA and telomerase activity in the endometrium of endometriosis patients. These finding suggest that replication potential of endometrial cells may have an important role in the pathogenesis of endometriosis.

Characterization of O2–CeO2 Interactions Using In Situ Raman Spectroscopy and First-Principle Calculations

Interactions between O(2) and CeO(2) are examined experimentally using in situ Raman spectroscopy and theoretically using density-functional slab-model calculations. Two distinct oxygen bands appear at 825 and 1131 cm(-1), corresponding to peroxo- and superoxo-like species, respectively, when partially reduced CeO(2) is exposed to 10 % O(2). Periodic density-functional theory (DFT) calculations aid the interpretation of spectroscopic observations and provide energetic and geometric information for the dioxygen species adsorbed on CeO(2). The O(2) adsorption energies on unreduced CeO(2) surfaces are endothermic (0.91<DeltaE(ads)<0.98 eV), while those on reduced surfaces are exothermic (-4. 0<DeltaE(ads)<-0.9 eV), depending on other relevant surface processes such as chemisorption and diffusion into the bulk. Partial reduction of surface Ce(4+) to Ce(3+) (together with formation of oxygen vacancies) alters geometrical parameters and, accordingly, leads to a shift in the vibrational frequencies of adsorbed oxygen species compared to those on unreduced CeO(2). Moreover, the location of oxygen vacancies affects the formation and subsequent dissociation of oxygen species on the surfaces. DFT predictions of the energetics support the experimental observation that the reduced surfaces are energetically more favorable than the unreduced surfaces for oxygen adsorption and reduction.

Immunoglobulin GM and KM genotypes in Korean patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by immune complex deposition. We genotyped immunoglobulin allotypes of G1M (f,z), G2M (n+,n-), G3M (b,g) and KM (1,3) in 142 Korean patients with SLE and 200 healthy controls to investigate the role of the allotypes in SLE. The allele frequency of G1M (z) was significantly higher in patients with SLE as compared to the healthy controls (94.6% vs. 84.3%, corrected P = 0.0004, OR 3.30, 95% CI 1.71-6.88). The frequency of G2M (n-) allele was also higher in patients with SLE (95.3% vs. 88.3%, corrected P = 0.008, OR = 2.71, 95% CI 1.38-5.72). Distribution of the tested allele frequencies for G3M and KM were not different between the patients and controls. In the respect of antibody production, there was increased genotype frequency of G1M (z/z) in anti-Sm(-) SLE (P = 0.023 vs. control, P = 0.042 vs. anti-Sm (+) SLE). In conclusion, particular genotypes at G1M (f,z) and G2M (n+,n-) loci are significantly associated with SLE. These immunoglobulin genes may contribute to the etiology of SLE and production of autoantibodies.