Low-level laser irradiation induces a transcriptional myotube-like profile in C2C12 myoblasts.

Low-level laser irradiation (LLLI) has been used as a non-invasive method to improve muscular regeneration capability. However, the molecular mechanisms by which LLLI exerts these effects remain largely unknown. Here, we described global gene expression profiling analysis in C2C12 myoblasts after LLLI that identified 514 differentially expressed genes (DEG). Gene ontology and pathway analysis of the DEG revealed transcripts among categories related to cell cycle, ribosome biogenesis, response to stress, cell migration, and cell proliferation. We further intersected the DEG in C2C12 myoblasts after LLLI with publicly available transcriptomes data from myogenic differentiation studies (myoblasts vs myotube) to identify transcripts with potential effects on myogenesis. This analysis revealed 42 DEG between myoblasts and myotube that intersect with altered genes in myoblasts after LLLI. Next, we performed a hierarchical cluster analysis with this set of shared transcripts that showed that LLLI myoblasts have a myotube-like profile, clustering away from the myoblast profile. The myotube-like transcriptional profile of LLLI myoblasts was further confirmed globally considering all the transcripts detected in C2C12 myoblasts after LLLI, by bi-dimensional clustering with myotubes transcriptional profiles, and by the comparison with 154 gene sets derived from previous published in vitro omics data. In conclusion, we demonstrate for the first time that LLLI regulates a set of mRNAs that control myoblast proliferation and differentiation into myotubes. Importantly, this set of mRNAs revealed a myotube-like transcriptional profile in LLLI myoblasts and provide new insights to the understanding of the molecular mechanisms underlying the effects of LLLI on skeletal muscle cells.

Reduction in the mRNA expression of sVEGFR1 and sVEGFR2 is associated with the selection of dominant follicle in cows.

The vascular endothelial growth factor (VEGF) is essential for follicular development by promoting follicular angiogenesis, as well as for the proliferation and survival of granulosa cells. The biological effects of VEGF are regulated by two membrane receptors, VEGFR1 and VEGFR2, and two soluble receptors, sVEGFR1 and sVEGFR2, which play an antagonistic role. Thus, the objective of this study was to identify the mRNA expression pattern of total VEGF, VEGFR1, VEGFR2, sVEGFR1 and sVEGFR2 in bovine preselected follicles (PRF) and post-selected follicles (POF). The mRNA expression of these five genes in both granulosa cells (GC) and theca cells (TC) was compared between follicles classified as PRF and POF based on their diameter and on their ratio of estradiol/progesterone (E2/P4). Results showed a lower expression of mRNA of sVEGFR1 and sVEGFR2 in POF than in PRF (p < .05). Regarding the mRNA expression of total VEGF, VEGFR1 and VEGFR2, there was no difference between POF and PRF follicles (p > .05). Our results showed that the mRNA expression of VEGFR2 and sVEGFR1 was more abundant than the expression of VEGFR1 and sVEGFR2, while GC was the main source of mRNA for total VEGF. On the other hand, TC was the follicular compartment where the receptors were most expressed. Our results suggest that non-dominant follicles maintain a greater concentration of the mRNA expression of both membrane and soluble VEGF receptors. On the other hand, follicular dominance is related to a reduction in the mRNA expression of sVEGFR1 and sVEGFR2, which may favour VEGF binding with VEGFR2 and, hence, improve the follicular health and development.

Ex-post analysis of landraces sympatric to a commercial variety in the center of origin of the potato failed to detect gene flow.

The possible introduction of genetically modified potato in the Andean region raises concerns about the unintentional introduction of transgenes into the native potato germplasm because it is perceived to convey negative impacts on biodiversity. We investigated this question by an ex-post analysis of existing landraces resulting from natural hybridization between an unknown landrace and the fertile commercial variety 'Yungay'. This variety can be regarded as exotic because it was bred in part from the southern Chilean germplasm of Solanum tuberosum Group Chilotanum. We sampled the landrace germplasm of 1,771 leaf samples comprising more than 400 different landraces from three regions where 'Yungay' and landraces have coexisted for 15-25 years in the Peruvian Andes. Simple sequence repeat (SSR) markers were used to identify putative hybrids based on allele sharing with those of 'Yungay'. The exclusion procedure was iterative, starting with the SSR markers with highest discriminating capacity based on allele frequency of the variety 'Yungay' in our large database of 688 landraces by 24 SSR makers. With only 12 of the 24 SSR markers assayed, all of the samples could be rejected as possible hybrids with 'Yungay' as a parent. This result demonstrates that the unintentional introduction of a transgene, not under farmers' selection, from a widely grown transgenic variety over a long period of time is unlikely to happen at a detectable scale. Our finding reinforces the prominent role of farmers in the selection and maintenance of landraces which, unlike hybrids, have specific characteristics that farmers appreciate.

Percentage of ubiquitinated spermatozoa does not correlate with fertilizing capacity of thawed bovine semen.

In the spermatozoa of some species, the ubiquitin-proteasome system detects altered proteins and tags them for elimination by the proteasome. In some species' ejaculates, a high proportion of ubiquitinated spermatozoa (i.e. those having ubiquitin bound to the altered or damaged membrane proteins) has been related to infertility. The aim of this study was to assess whether the percentage of ubiquitinated spermatozoa relates to fertility of dairy bulls and whether ubiquitination increases during protein remodelling that occurs during in vitro spermatic capacitation. Thirty-two frozen semen straws from four high-fertility (ReproMax(®) ) and four normal-fertility (Normal) Holstein-Friesian sires were evaluated. Ubiquitinated and capacitated spermatozoa were quantified by sperm ubiquitin tag immunoassay and chlortetracycline stain, respectively. Fertilizing capacity of sires was assessed by in vitro fertilization. No differences were found between Normal and ReproMax(®) sires with regard to the observed percentage of ubiquitinated spermatozoa (42.97 ± 3.69% and 49.68 ± 9.27%, respectively; p > 0.05). Additionally, no differences were found in the percentage of ubiquitinated spermatozoa as a consequence of spermatic capacitation in either Normal (42.97 ± 3.69% before capacitation vs 44.67 ± 7.5% after; p > 0.05) or ReproMax(®) sires (49.68 ± 9.27% before vs 45.05 ± 7.51% after; p > 0.05). The percentage of ubiquitinated spermatozoa in a thawed sperm samples did not correlate with its in vitro fertilizing capacity; thus, this assay does not prove useful to detect in vivo fertility differences between sires. Additionally, protein degradation occurring during remodelling of the spermatozoon plasma membrane during the capacitation process does not seem to involve the ubiquitin-proteasome system.

Genetic effects on sperm design in the zebra finch.

Sperm design and function are important determinants of male reproductive success and are expected to be under strong selection. The way that spermatozoa phenotypes evolve is poorly understood, because there have been few studies of the quantitative genetics of sperm. Here we show, in the zebra finch Taeniopygia guttata, an extraordinary degree of inter-male variation in sperm design that is independent of sperm swimming velocity. A quantitative genetics study using data from over 900 zebra finches in a complex breeding experiment showed that sperm head, mid-piece and flagellum length are heritable, that negative genetic correlations exist between sperm traits, and that significant indirect (maternal) genetic effects exist. Selection on the zebra finch sperm phenotype may be low because sperm competition is infrequent in this species, and this, in combination with negative genetic correlations and maternal genetic effects, may account for the variation in sperm phenotype between males. These results have important implications for the evolution of sperm in other taxa.

Cervical Squamous Intraepithelial Lesions Are Associated with Differences in the Vaginal Microbiota of Mexican Women.

Cervical cancer is an important health concern worldwide and is one of the leading causes of death in Mexican women. Previous studies have shown changes in the female genital tract microbe community related to human papillomavirus (HPV) infection and cervical cancer; yet, this link remains unexplored in many human populations. This study evaluated the vaginal bacterial community among Mexican women with precancerous squamous intraepithelial lesions (SIL). We sequenced the V3 region of the 16S rRNA gene in cervical samples from 228 Mexican women, including 121 participants with SIL, most of which were HPV positive, and 107 healthy women without HPV infection or SIL. The presence of SIL was associated with changes in composition (beta diversity) and with a higher species richness (Chao1). A comparison of HPV-positive women with and without SIL showed that microbiota changes occurred even in the absence of SIL. Multivariate association with linear models (MaAsLin) analysis yielded independent associations between HPV infection and an increase in the relative abundance of Brachybacterium conglomeratum and Brevibacterium aureum as well as a decrease in two Lactobacillus iners operational taxonomic units (OTUs). We also identified a positive independent association between HPV-16, the most common HPV subtype linked to SIL, and Brachybacterium conglomeratum. Our work indicates that HPV infection leading to SIL is primarily associated with shifts in vaginal microbiota composition, some of which may be specific to this human population. IMPORTANCE Human papillomavirus (HPV) plays a critical role in cervical carcinogenesis but is not sufficient for cervical cancer development, indicating the involvement of other factors. The vaginal microbiota is an important factor in controlling infections caused by HPV, and, depending on its composition, it can modulate the microenvironment in vaginal mucosa against viral infections. Ethnic and sociodemographic factors influence differences in vaginal microbiome composition, which underlies the dysbiotic patterns linked to HPV infection and cervical cancer across different populations of women. Here, we provide evidence for associations between vaginal microbiota patterns and HPV infection linked to ethnic and sociodemographic factors. To our knowledge, this is the first report of the species Brevibacterium aureum and Brachybacterium conglomeratum linked to HPV infection or squamous intraepithelial lesions (SIL).

Genetic and environmental parameters for milk production, udder health, and fertility traits in Mexican Holstein cows.

Genetic and phenotypic parameters for Mexican Holstein cows were estimated for first- to third-parity cows with records from 1998 to 2003 (n=2,971-15,927) for 305-d mature equivalent milk production (MEM), fat production (MEF), and protein production (MEP), somatic cell score (SCS), subsequent calving interval (CAI), and age at first calving (AFC). Genetic parameters were obtained by average information matrix-REML methodology using 6-trait (first-parity data) and 5-trait (second- and third-parity data) animal models. Heritability estimates for production traits were between 0.17+/-0.02 and 0.23+/-0.02 for first- and second-parity cows and between 0.12+/-0.03 and 0.13+/-0.03 for third-parity cows. Heritability estimates for SCS were similar for all parities (0.10+/-0.02 to 0.11+/-0.03). For CAI, estimates of heritability were 0.01+/-0.05 for third-parity cows and 0.02+/-0.02 for second-parity cows. The heritability for AFC was moderate (0.28+/-0.03). No unfavorable estimates of correlations were found among MEM, MEF, MEP, CAI, and SCS. Estimates of environmental and phenotypic correlations were large and positive among production traits; favorable between SCS and CAI; slightly favorable between MEM, MEF, and MEP and SCS, between AFC and SCS, and between SCS and CAI; and small but unfavorable between production traits and CAI. Estimates of genetic variation and heritability indicate that selection would result in genetic improvement of production traits, AFC, and SCS. Estimates of both heritability and genetic variation for CAI were small, which indicates that genetic improvement would be difficult.

Selection response for milk production in conventional production systems in Mexico, using genetic evaluations of Holstein sires from Canada and the United States.

Polynomial regression models of the first, second, and third order were used to fit milk production deviations of daughters in Mexico on Canadian and US predicted transmitting ability values for 305-d mature-equivalent milk production (kg). For the pairs Canada-Mexico and Mexico-United States, 40 and 73 bulls with a minimum reliability of 0.75 were analyzed, respectively. Genetic correlations between pairs of countries were also estimated. The parameters were evaluated for all data, and for sires grouped according to the mean of the average phenotypic milk production (high and low) of their daughters' herd mates. Quadratic and cubic effects were not significant in any analysis. From linear regression models, slopes of Mexican daughter deviations on US and Canadian predicted transmitting abilities were 1.01 and 0.93, respectively. Slopes were greater but intercepts were smaller for the high versus low level of production of the sires' herd mates in Mexico. A greater difference between the genetic correlations was found for the high versus low environmental level than for the low level (0.79 vs. 0.70) for Mexico-US data compared with Canada-Mexico data (0.81 vs. 0.78). Genetic correlations between Mexico and the United States (0.74), and between Mexico and Canada (0.77), were smaller than the genetic correlation between the same Canadian and US sires (0.92), suggesting the presence of a moderate degree of genotype-environment interaction for milk production between Canada and the United States, and Mexico.

Phylogenetic analysis of ORF5 and ORF7 of porcine reproductive and respiratory syndrome (PRRS) virus and the frequency of wild-type PRRS virus in México.

Porcine reproductive and respiratory syndrome (PRRS) is caused by a genetically diverse RNA virus and is an economically significant disease in the swine industry. In this study, a total of 8,126 serum samples were obtained from 275 technified and semi-technified farms belonging to 30 of the 32 states of Mexico and representative of the eight regions of the country. Anti-PRRSv antibodies against the PRRS vaccine and an isolated wild Mexican virus were tested by ELISA. Antibodies were found in 15%-49% of the tested sera, with 2.4%-9.8% against the vaccine and 7.7%-26% against the wild virus. The PRRSv virus was detected by RT-PCR in 77 of the 1,630 pooled samples tested, representing seven of the eight geographic regions into which the Mexican Republic is divided. The complete sequences of open reading frames 5 and 7 from 20 PRRSv-positive samples were determined. The analysis of the sequences together with the previously published sequences of historic strains revealed that all the strains belonged to the one, five and eight lineages of the PRRSV2. Striking differences, particularly in ORF5 and ORF7, were found between sequences of the strains and the reference virus, due to insertions and substitutions in positions that play key roles in the recognition, structure and function of the virus. Overall, these results established the magnitude of PRRS virus genetic diversity, and the most frequent virus strain that predominates in Mexico. The PRRSV2 is presented in the porcine population of Mexico; the circulating strains have important changes in ORF5 and ORF7, which probably explain the results obtained in the serological analysis of the wild virus and vaccine strains.

Short communication: Changes in the association between milk yield and age at first calving in holstein cows with herd environment level for milk yield.

The aim of this study was to evaluate the effect of herd environment class on the genetic and phenotypic relationships of mature equivalent milk yield (MY) on age at first calving (AFC). Data analyzed were 248,230 first parity records of Holstein cows, daughters of 588 sires in 3,042 herds in the United States. Heritability for AFC was 0.33 +/- 0.01 and 0.20 +/- 0.01 in high and low environment herds, respectively, and 0.47 +/- 0.01 in the complete data set. The correlation between AFC sires' predicted breeding values of low and high classes was 0.69. Genetic correlations between MY and AFC were -0.52 +/- 0.02 and -0.31 +/- 0.03 in high and low environment herds, respectively, and -0.44 +/- 0.02 in the complete data set representing intermediate environments. If selection is based on the whole data set, expected correlated responses for AFC estimated as a result of 1,000 kg of genetic gain in MY, for high and low herd environment herds were -26.1 and -15.3 d, respectively, and -32.6 for the complete data set; hence the highest reduction in AFC occurs in intermediate environment herds. Different estimates of the heritability of AFC, the correlation between AFC breeding values of low and high classes as well as changes in the genetic correlation between MY and AFC across environments indicate genotype x environment interaction. Caution in interpretation is warranted because genetic relationships are dynamic, especially in populations undergoing selection. Current relationships may differ from those during the time period of the present study (1987-1994). Notwithstanding this possibility, methods and findings from the present study provide insight about the complexity of genetic association and genotype x environment interactions between AFC and MY.

Porcine circovirus type 2 antibody detection in backyard pigs from Mexico City.

PCV2 antibodies have been found in pigs from all continents. However, this finding has been mainly studied in domestic swine reared under intensive production conditions. Mexico City, with a human population over 19 million in 2005, has both urban and rural areas. The pig production in its rural area is based on small family backyard farms. Taking into account this rather unique form of rearing pigs, the objective of this study was to determine the seroprevalence in backyard pigs from the rural area of Mexico City. A total of 695 backyard pig serum samples from 108 small family farms belonging to seven municipal areas were studied by immunoperoxidase monolayer assay technique. One hundred six out of the 108 family farms (98.14%) had at least one positive serum sample. On the other hand, 136 (19.57%), 264 (37.99%) and 248 (34.82%) pigs had low, intermediate and high titres to PCV2, respectively. Only 53 samples (7.63%) were negative for PCV2 antibodies. No apparent differences in antibody titre groups were observed among backyard pigs from the different municipal areas. In conclusion, the present study, the first one performed in this kind of extensively produced pigs, indicates that PCV2 is ubiquitous in backyard pigs from Mexico City.

Fertility responses of Mexican Holstein cows to US sire selection.

Genetic relationships between 2 fertility traits and milk production were investigated using mature-equivalent lactation records of 55,162 daughters of 1,339 Holstein sires in Mexico and 499,401 daughters of 663 Holstein sires in the northeastern United States. Data sets contained yields in first and second lactation, age at first calving (AFC), and calving interval (CI). There were 474 US sires in common between countries. A herd-year standard deviation criterion defined nonoverlapping low- (< or = 1,300 kg) and high- (> or = 1,600 kg) opportunity Mexican herd environments and a low-opportunity (< or = 1,024 kg) US environment. Genetic variances for the average Mexican herd (all data) for AFC and CI were 65 and 85% as large as those obtained from half-sisters in the average US herd. Genetic correlations for first-lactation milk in the average US herd and AFC and CI in the average Mexican environment were unfavorable (0.18 and 0.10). Regression coefficients of AFC in Mexican environments on US genetic gain in milk ranged from 2 to 7 d/1,000 kg. However, the favorable predicted response in AFC from genetic gain in milk in Mexican environments, like those in average US herds, ranged from -4 to -7 d/1,000 kg (r(g) = - 0.20). This unequal AFC response may indicate genotype by environment interaction in fitness performance or differential breeding management of high and low yielding Mexican cows. The potential effects of age at first service of breeding females need to be disentangled to accurately assess genetic improvement needs for Mexican Holstein herds.

Removal of oxyfluorfen from spiked soils using electrokinetic soil flushing with the surrounding arrangements of electrodes.

This work reports the results of a study in which the remediation of soil that undergoes an accidental discharge of oxyfluorfen is carried out by using electrokinetic soil flushing (EKSF). Two different electrode configurations were tested, consisting of several electrodes surrounding an electrode of different polarity (so-called 1A6C, one anode surrounded by six cathodes, and 1C6A, one cathode surrounded by six cathodes). A pilot plant scale was used (with a soil volume of 175dm(3)) to perform the studies. During the tests, different parameters were measured daily (flowrates, pH, electrical conductivity and herbicide concentration in different sampling positions). Furthermore, at the end of the test, a complete post-mortem analysis was carried out to obtain a 3-D map of the pollution, pH and electrical conductivity in the soil. The results demonstrate that electrode arrangement is a key factor for effective pollutant removal. In fact, the 1A6C configuration improves the removal rate by 41.3% versus the 27.0% obtained by the 1C6A configuration after a period of 35days. Finally, a bench mark comparison of this study of soil remediation polluted with 2,4-D allows for significant conclusions about the scale-up and full-scale application of this technology.

Evaluation of vascular endothelial growth factor gene and protein expression in canine metastatic mammary carcinomas.

Vascular endothelial growth factor (VEGF) is a potent angiogenic factor that could be associated with the induction of endothelial cell proliferation and metastasis. In this study, we evaluated VEGF gene and protein expression in canine mammary tumors (CMT), including metastatic carcinomas, to determine if there is an influence of this marker in the malignant processes and aggressiveness of CMT. We also compared VEGF protein levels with clinicopathological features. The VEGF gene and protein expression levels were evaluated by reverse transcription-quantitative polymerase chain reaction and immunohistochemistry, respectively, in normal mammary gland samples, benign mammary tumors, nonmetastatic mammary carcinomas, and metastatic mammary carcinomas. High VEGF gene and protein levels were associated with malignant tumors compared with normal mammary glands (p = 0.0089 and p < 0.0001, respectively). Benign tumors showed an increased VEGF protein expression compared with normal samples (p = 0.0467). No significant differences in VEGF gene or protein levels were detected between benign and malignant tumors or between nonmetastatic and metastatic carcinomas, suggesting an absence in the correlation of VEGF with malignant processes and aggressiveness of CMT. No correlation of VEGF expression with clinical and histopathological parameters was observed, suggesting that VEGF could be important in the beginning of the mammary gland carcinogenic process and could be related to survival time.

Variation in the volume of zebra finch song control nuclei is heritable: developmental and evolutionary implications.

In many songbird species, females prefer males that sing a larger repertoire of syllables. Males with more elaborate songs have a larger high vocal centre (HVC) nucleus, the highest structure in the song production pathway. HVC size is thus a potential target of sexual selection. Here we provide evidence that the size of the HVC and other song production nuclei are heritable across individual males within a species. In contrast, we find that heritabilities of other nuclei in a song-learning pathway are lower, suggesting that variation in the sizes of these structures is more closely tied to developmental and environmental differences between individuals. We find that evolvability, a statistical measure that predicts response to selection, is higher for the HVC and its target for song production, the robustus archistriatalis (RA), than for all other brain volumes measured. This suggests that selection based on the functions of these two structures would result in rapid major shifts in their anatomy. We also show that the size of each song control nucleus is significantly correlated with the song related nuclei to which it is monosynaptically connected. Finally, we find that the volume of the telencephalon is larger in males than in females. These findings begin to join theoretical analyses of the role of female choice in the evolution of bird song to neurobiological mechanisms by which the evolutionary changes in behaviour are expressed.

Influence of admixed carboxymethylcellulose on release of 4-aminopyridine from hydroxypropyl methylcellulose matrix tablets.

Among different technological variables that influence drug release from hydrophilic matrices, the use of mixtures of polymers represents a potential way of achieving a variety of release properties. Tablets of the model drug 4-aminopyridine with hydroxypropyl methylcellulose were prepared with different proportions of polymer content as well as with different proportions of admixed carboxymethylcellulose (CMC) in the range up to 35% (based on the total polymer content). The matrices release behavior was examined by absorption of samples at 261 nm (USP 23 apparatus 2, paddle, at 50 rpm) using 0.1 N HCl and 0.2 M phosphate buffer as dissolution media. Increasing proportions of CMC in the polymer mixture lead to decreasing dissolution rates, in a range of k=0.094-0.036 for HCl and k=0.044--0.009 for phosphate buffer. The release mechanism in HCl is predominantly controlled by diffusion (n=0.46--0.62), while in phosphate buffer it is controlled, as reported previously, by diffusion/relaxation (n=0.58--0.85) and near zero order release at high CMC concentrations. Approximately doubling the total polymer content gives lower release rates for HCl in the range k=0.038--0.015 and for phosphate buffer k=0.0099--0.0034. Near zero order release is observed only at pH 7.4 (n=0.79--0.96). Decreasing release constant values show a logarithmic relationship with increasing values of the exponent n. This indicates that zero-order release occurs with sufficiently reduced release rate.

Heritability of plasma von Willebrand factor antigen concentration in German Wirehaired pointers.

We applied quantitative genetic analyses to a population of German Wirehaired pointer dogs affected with type 2 von Willebrand disease. Plasma von Willebrand factor (vWF) protein concentration measured as vWF antigen (vWF:Ag), clinical history, and pedigree data were compiled for 331 dogs over a 5-year test period. Eight dogs had histories of abnormal bleeding and had markedly decreased plasma vWF:Ag concentrations (<1%). Four per cent of the dogs were inbred, with an average inbreeding of 2.52%. The estimated heritability of plasma vWF concentration was 0.52. We found a major gene effect on vWF concentration. Using a single gene locus model and two different prediction methods, the upper threshold value for the aa genotype was less than 1% vWF:Ag, and the optimal threshold value for discrimination between the AA and Aa genotypes was between 68% and 72% vWF:Ag. Our analyses indicate that phenotype, assigned on the basis of a single vWF:Ag determination, is heritable and can be applied for selective breeding in a von Willebrand disease test programme.

Horizontal appendicular dysmetria in four patients with a typical Wallenberg's syndrome.

During the acute stage of a Wallenberg's syndrome ipsilateral appendicular dysmetria is frequently seen. The dysmetria is more apparent in the ipsilateral upper extremity. These patients also have a peculiar type of dysmetric eye movements that are characterized by hypermetric saccades toward the side of the lesion and hypometric saccades to the opposite side. We examined four patients with acute Wallenberg's syndrome and found horizontal dysmetria of the affected extremity. Hypermetric arm and hand movements were present to the side of the lesion and hypometric movements toward the opposite side. This type of dysmetria is probably related to the same patophysiological mechanism that underlies dysmetric eye movements in the Wallenberg's syndrome. The dysmetria tends to disappear with time although it continues to be present in some patients six months after the ischemic damage.