Genetic variability among and within domestic Old and New World camels at the α-lactalbumin gene (LALBA) reveals new alleles and polymorphisms responsible for differential expression

α-Lactalbumin (α-LA), which is encoded by the LALBA gene, is a major whey protein that binds to Ca2+ and facilitates lactose synthesis as a regulatory subunit of the synthase enzyme complex. In addition, it has been shown to play central roles in immune modulation, cell-growth regulation, and antimicrobial activity. In this study, a multitechnical approach was used to fully characterize the LALBA gene and its variants in both coding and regulatory regions for domestic camelids (dromedary, Bactrian camel, alpaca, and llama). The gene analysis revealed a conserved structure among the camelids, but a slight difference in size (2,012 bp on average) due to intronic variations. Promoters were characterized for the transcription factor binding sites (11 found in total). Intraspecies sequence comparison showed 36 SNPs in total (2 in the dromedary, none in the Bactrian camel, 22 in the alpaca, and 12 in the llama), whereas interspecies comparison showed 86 additional polymorphic sites. Eight SNPs were identified as trans-specific polymorphisms, and 2 of them (g.112A>G and g.1229A>G) were particularly interesting in the New World camels. The first creates a new binding site for transcription factor SP1. An enhancing effect of the g.112G variant on the expression was demonstrated by 3 independent pGL3 gene reporter assays. The latter is responsible for the p.78Ile>Val AA replacement and represents novel allelic variants (named LALBA A and B). A link to protein variants has been established by isoelectric focusing (IEF), and bioinformatics analysis revealed that carriers of valine (g.1229G) have a higher glycosylation rate. Genotyping methods based on restriction fragment length polymorphism (PCR-RFLP) were set up for both SNPs. Overall, adenine was more frequent (0.54 and 0.76) at both loci. Four haplotypes were found, and the AA and GA were the most common with a frequency of 0.403 and 0.365, respectively. Conversely, a putative biological gain characterizes the haplotype GG. Therefore, opportunities for rapid directional selection can be realized if this haplotype is associated with favorable milk protein properties. This study adds knowledge at the gene and protein level for α-LA (LALBA) in camelids and importantly contributes to a relatively unexplored research area in these species.

A novel allelic donkey β-lactogobulin I protein isoform generated by a non-AUG translation initiation codon is associated with a nonsynonymous SNP

β-Lactoglobulin I (β-LG I) is one of the most important whey proteins in donkey milk. However, to our knowledge, there has been no study focusing on the full nucleotide sequences of this gene (BLG I). Current investigation of donkey BLG I gene is very limited with only 2 variants (A and B) characterized so far at the protein level. Recently, a new β-LG I variant, with a significantly higher mass (+1,915 Da) than known variants has been detected. In this study, we report the whole nucleotide sequence of the BLG I gene from 2 donkeys, whose milk samples are characterized by the β-LG I SDS-PAGE band with a normal electrophoretic mobility (18,514.25 Da, β-LG I B1 form) the first, and by the presence of a unique β-LG I band with a higher electrophoretic mobility (20,428.5 Da, β-LG I D form) the latter. A high genetic variability was found all over the 2 sequenced BLG I alleles. In particular, 16 polymorphic sites were found in introns, one in the 5' flanking region, 3 SNPs in the 5' untranslated region and one SNP in the coding region (g.458G > A) located at the 40th nucleotide of exon 2 and responsible for the AA substitutions p.Asp28 > Asn in the mature protein. Two SNPs (g.920-922CAC > TGT and g.1871G/A) were genotyped in 93 donkeys of 2 Italian breeds (60 Ragusana and 33 Amiatina, respectively) and the overall frequencies of g.920-922CAC and g.1871A were 0.3065 and 0.043, respectively. Only the rare allele g.1871A was observed to be associated with the slower migrating β-LG I. Considering this genetic diversity and those found in the database, it was possible to deduce at least 5 different alleles (BLG I A, B, B1, C, D) responsible for 4 potential β-LG I translations. Among these alleles, B1 and D are those characterized in the present research, with the D allele of real novel identification. Haplotype data analysis suggests an evolutionary pathway of donkey BLG I gene and a possible phylogenetic map is proposed. Analyses of mRNA secondary structure showed relevant changes in the structures, as consequence of the g.1871G > A polymorphism, that might be responsible for the recognition of an alternative initiation site providing an additional signal peptide. The extension of 19 AA sequence to the mature protein, corresponding to the canonical signal peptide with an additional alanine residue, is sufficient to provide the observed molecular weight of the slower migrating β-LG I encoded by the BLG I D allele.

Sequencing of lipoprotein lipase gene in the Mediterranean river buffalo identified novel variants affecting gene expression

Lipoprotein lipase (LPL) is a key enzyme for lipid metabolism, playing a fundamental role in the composition of fat in adipose tissue and milk. The LPL gene has been seldom investigated in dairy ruminants and barely studied in river buffalo (Bubalus bubalis). The aim of this work was to explore the genetic diversity of LPL and its promoter and to identify functional mutations, using a combined approach based on sequencing, dual-color electrophoretic mobility shift assay, and quantitative PCR. Thirteen consensus sequences for transcription factors were found in the promoter. Eleven SNP were detected, and the attention was focused on the SNP with potential functional effects: g.-446A>G, because the presence of G created a consensus motif for the transcription factor Sp1, and g.107A>G, which was the only exonic SNP. We developed PCR-RFLP methods for genotyping the 2 SNP and calculated the allele frequencies. A strong linkage disequilibrium (D' = 1; r² = 0.903) was found between the 2 SNP. The dual-color electrophoretic mobility shift assay demonstrated that only genotype g.-446GG allowed the binding of the Sp1 transcription factor, resulting in overexpression of the gene (~2.5 fold), as confirmed by the quantitative PCR results. Haploinsufficiency is proposed as a regulation mechanism. This study adds further knowledge on the structure of the LPL gene and its expression in river buffalo, with potential effects on milk qualitative and quantitative production.

The single nucleotide polymorphism g.133A>C in the stearoyl CoA desaturase gene (SCD) promoter affects gene expression and quali-quantitative properties of river buffalo milk

The stearoyl-CoA desaturase (SCD) gene has been investigated in depth in ruminants because of its effect on milk fat composition. In river buffalo, the single nucleotide polymorphism (SNP) g.133A>C in the gene promoter has been associated with milk quality and yield. However, the biological reason for such effects remains unexplored. In this study, we combined mRNA profile analysis, an electromobility shift assay, and quantitative PCR to elucidate the role of this SNP on gene transcription and its effects on milk fat traits. A preliminary genotyping of g.133A>C was carried out on a group of 303 river buffaloes to choose individuals for the downstream applications. Analysis of allele frequencies showed an increase in the minor allele C (0.25) compared with previous findings (0.16). Six animals (2 for each genotype) were chosen for cloning and 216 positive cDNA recombinant clones for SCD (72 per genotype) were analyzed by PCR. All clones showed the same length on agarose gel; therefore, random clones were chosen for sequencing. No qualitative differences were found and all gene transcripts assembled correctly. An electrophoretic mobility shift assay was performed to evaluate the binding of the transcription factor Sp1 to DNA sequences including g.133A>C. Genotype CC showed a higher binding (mean ± standard error of the mean) than genotype AA in 2 different conditions [Enzo buffer (EB), Enzo Life Science Inc., Farmingdale, NY: 201.77 ± 4.06 vs. 141.65 ± 3.77 band intensity values and Poletto buffer (PB): 95.90 ± 1.15 vs. 67.30 ± 2.14 band intensity values]. The subsequent quantitative PCR confirmed the upregulation of the CC genotype compared with the AA and AC genotypes. The association study with milk fat traits revealed a favorable effect of allele C. The heterozygous genotype had the highest values for monounsaturated fatty acids, oleic acid (C18:1 cis-9), polyunsaturated fatty acids, and odd- and branched-chain fatty acids, and the lowest values for saturated fatty acids and atherogenic and thrombogenic indices; the heterozygous genotype differed significantly from the AA genotype. The AC genotype has previously been associated with higher milk yield. Therefore, the g.133A>C SNP is a marker with dual effects and is an interesting candidate for assisted selection programs in river buffalo. These data clarified the biological role of the SNP g.133A>C in the SCD promoter and how it affects gene function, providing important knowledge on the genetic background of lipid metabolism, including the future possibility of selecting alleles with quantitatively or qualitatively favorable effects.

Remarkable genetic diversity detected at river buffalo prolactin receptor (PRLR) gene and association studies with milk fatty acid composition

Prolactin is an anterior pituitary peptide hormone involved in many different endocrine activities and is essential for reproductive performance. This action is mediated by its receptor, the prolactin receptor, encoded by the PRLR gene. In this study, we sequenced and characterized the Mediterranean river buffalo PRLR gene (from exon 3 to 10), and we found remarkable genetic diversity. In particular, we found 24 intronic polymorphisms and 13 exonic SNPs, seven of which were non-synonymous. Furthermore, the polymorphisms identified in the 3'-UTR were investigated to establish their possible influence on microRNA binding sites. Considering all the amino acid changes and the observed allelic combinations, it is possible to deduce at least six different translations of the buffalo prolactin receptor and, consequently, the presence at the PRLR gene of at least six alleles. Furthermore, we identified a deletion of a CACTACC heptamer between nucleotides 1102 and 1103 of exon 10 (3'-UTR), and we developed an allele-specific PCR to identify the carriers of this genetic marker. Finally, the SNP g.11188A>G, detected in exon 10 and responsible for the amino acid replacement p.His328Arg, was genotyped in 308 Italian Mediterranean river buffaloes, and an association study with milk fat traits was carried out. The statistical analysis showed a tendency that approached significance for the AA genotype with higher contents of odd branched-chain fatty acids. Thus, our results suggest that the PRLR gene is a good candidate for gene association studies with qualitative traits related to buffalo milk production.

Transcript analysis at DGAT1 reveals different mRNA profiles in river buffaloes with extreme phenotypes for milk fat

Buffalo DGAT1 (diacylglycerol O-acyltransferase 1) was mainly investigated for the characterization of the gene itself and for the identification of the K232A polymorphism, similar to what has been accomplished in cattle, although no information has been reported so far at the mRNA level. The importance of DGAT1 for lipid metabolism led us to investigate the transcript profiles of lactating buffaloes characterized as high (9.13 ± 0.23) and low (7.94 ± 0.29) for milk fat percentage, and to explore the genetic diversity at the RNA and DNA level. A total of 336 positive clones for the DGAT1 cDNA were analyzed by PCR and chosen for sequencing according to the differences in length. The clone assembling revealed a very complex mRNA pattern with a total of 21 transcripts differently represented in the 2 groups of animals. Apart from the correct transcript (17 exons long), the skipping of exon 12 is the most significant in terms of distribution of clones with 11.6% difference between the 2 groups, whereas a totally different mRNA profile was found in approximately 12% of clones. The sequencing of genomic DNA allowed the identification of 10 polymorphic sites at the intron level, which clarify, at least partially, the genetic events behind the production of complex mRNA. Genetic diversity was found also at the exon level. The single nucleotide polymorphism c.1053C>T represents the first example of polymorphism in a coding region for the DGAT1 in the Italian Mediterranean breed. To establish whether this polymorphism is present in other buffalo breeds, a quick method based on PCR-RFLP was set up for allelic discrimination in the Italian Mediterranean and the Romanian Murrah (200 animals in total). The alleles were equally represented in the overall population, whereas the analysis of the 2 breeds showed different frequencies, likely indicating diverse genetic structure of the 2 breeds. The T allele might be considered as the ancestral condition of the DGAT1 gene, being present in the great part of the sequenced species. These data add knowledge at the transcript and genetic levels for the buffalo DGAT1 and open the opportunity for further investigation of other genes involved in milk fat metabolism for the river buffalo, including the future possibility of selecting alleles with quantitative or qualitative favorable effects (or both).

Lama glama αS1-casein: Identification of new polymorphisms in the CSN1S1 gene

South American camelids have been poorly genetically investigated and little information is available in llamas (Lama glama) regarding the diversity of the caseins at the protein and gene level. Exon skipping and duplication events previously reported in the α_S1-casein gene (CSN1S1) led us to investigate the genetic variability at this locus. Seventy-two positive clones for the α_S1-casein transcripts were analyzed and randomly sequenced. The comparative analysis of the sequences revealed 2 transitions, c.366A>G and c.690T>C, at the 10th nucleotide of exon 12 and 94 bp of exon 19, respectively. These SNP are responsible for 2 amino acid changes, Ile→Val in position 86 and Tyr→His in position 194 of the mature protein. Both polymorphisms clarify the genetic events behind the protein variants A and B. This result was confirmed by isoelectric focusing analysis of llama milk samples. Quick methods based on PCR-RFLP and allele-specific PCR were set up for allelic discrimination in a population of 128 animals. Based on genotyping results, 4 haplotypes were observed and the estimated frequencies indicated B as the most common haplotype (0.629) in the investigated population. These data add knowledge to the genetic variability of a species little investigated, and open opportunity for new investigation in the field of milk protein for South American camelids, including the possibility, in the future, to select alleles with favorable characteristics.

Mediterranean river buffalo CSN1S1 gene: search for polymorphisms and association studies

The aim of the present study was to investigate the variability at CSN1S1 locus of the Italian Mediterranean river buffalo and to study possible allele effects on milk yield and its composition. Effects of parity, calving season and month of production were also evaluated. Three single-nucleotide polymorphisms were detected. The first mutation, located at position 89 of the 17th exon (c.628C>T), is responsible for the amino acid change p.Ser178 (B allele)/Leu178 (A allele). The other two polymorphisms, detected at the positions 144 (c.882G>A) and 239 (c.977A>G) of 19th exon, respectively, are silent (3ʹ UTR, untranslated region). Associations between the CSN1S1 genotypes and milk production traits were investigated using 4122 test day records of 503 lactations from 175 buffalo cows. Milk yield, fat and protein percentages were analysed using a mixed linear model. A significant association between the c.628C>T SNP and the protein percentage was found. In particular, the CC genotype showed an average value ~0.04% higher than the CT and TT genotypes. The allele substitution effect of cytosine into thymine was –0.014, with a quite low (0.3%) protein percentage contribution to total phenotypic variance. A large dominance effect was detected. Characterisation of the CSN1S1 transcripts and a method based on MboI amplification created restriction site PCR for a rapid genotyping of c.628C>T are provided.

127 THYMIDINE SYNCHRONIZATION OF IN VITRO DEVELOPMENT OF BOVINE EMBRYOS

Excess thymidine is capable of synchronizing lymphocyte cultures in vitro by acting with a feed-back mechanism during the S phase of the cell cycle (Harper 2005 Methods Mol. Biol. 296, 157–166). The possibility to synchronize the embryonic growth can be a good strategy for future epigenetic studies. The present study was undertaken to test whether excess thymidine could also synchronize in vitro development of bovine embryos. Abattoir-derived cumulus–oocyte complexes (COC) of the Agerolese breed of cattle were matured in vitro using standard procedures. After maturation, COCs were transferred in drops of 300 µL of IVF-TALP (25/drop) and covered with mineral oil. Frozen sperm from a bull were selected by centrifugation on a Percoll discontinuous gradient (45 to 80%). The pellet was diluted in IVF medium and added to the COC at the concentration of 1 × 106 sperm mL–1. After 18–20 h of gametes co-incubation, presumptive zygotes were denuded and cultured in SOF medium containing different concentrations of thymidine (0, 300, 600, 1200, 2400 µg mL–1, final concentrations). The day after (Day 2) presumptive zygotes were washed four times in fresh SOF, classified morphologically under a stereomicroscope as not divided (n.d.), 2 cells, 3–8 cells, and 9–32 cells and cultured in standard SOF at 39°C in a humidified mixture of 5% CO2,7% O2, and 88% N2. On Day 3, the embryos were again examined for the growth stage in relation to the synchronization effects. On Day 7, the embryos were evaluated for the final growth efficiency (cleavage stage and blastocyst formation). The experiment was replicated 4 times (except the 2400 µg mL–1 condition, which was replicated 2 times because of its clear toxic effect). Data were analyzed by ANOVA test. At Day 2, there were no differences between groups whatever the concentration (n.d.–2 cells: 59.7 ± 11.2, 52.9 ± 26.3, 56.1 ± 14.6, 66.0 ± 2.8, 38.0 ± 11.3; 3–8 cells : 40.3 ± 11.2, 47.1 ± 26.3, 43.9 ± 14.6, 34.0 ± 2.8, 59.9 ± 9.5; respectively for 300, 600, 1200, 2400, and control), while differences at Day 3 and 7 are shown in Table 1. The dosage of 300 µg mL–1 slowed embryo development without altering the developmental rate, whereas the other dosages were somewhat toxic to the zygotes, affecting the final percentage of blastocysts. Table 1.State of development of zygotes on Day 3 and Day 7 (cleavage and embryo rate)

Molecular characterization and genetic variability at κ-casein gene (CSN3) in camels

κ-casein is a glycosilated protein belonging to a family of phosphoproteins (αs1, β, αs2, κ) that represent the major protein component in mammalian milk. κ-casein plays an essential role in the casein micelle stabilization, determining the size and the specific function. In the present paper, we report for the first time the characterization of the nucleotide sequence of the whole κ-casein-encoding gene (CSN3) plus 1045 nucleotides at the 5' flanking region in Camelus dromedarius. The promoter region and the complete cDNA were also provided for the first time in Camelus bactrianus. The gene is spread over 9.3kb and consists of 5 exons varying in length from 33bp (exon 3) to 494bp (exon 4), and 4 introns from 1200bp (intron 3) to 2928bp (intron 2). Highly conserved sequences, located in the 5' flanking region, have been found. The regulatory regions of camels seems to be more related to equids than to other compared species. 17 polymorphic sites have been detected, one of these (g.1029T>C) is responsible for the creation of a new putative consensus sequence for the transcription factor HNF-1. In general, these SNPs are the first reported in camels for casein loci. Finally, seven interspersed repeated elements were also identified at intronic level.

X-Y aneuploidy rate in sperm of two "minor" breeds of cattle (Bos taurus) by using dual color fluorescent in situ hybridization (FISH)

The present study reports on the frequency of X-Y aneuploidy in the sperm population of two minor cattle breeds reared in Italy, namely Modicana and Agerolese, which are listed in the "Anagraphic Register of autochthonous cattle populations with limited distribution". More than 50 000 sperm nuclei from 11 subjects (5 and 6, respectively for each breed) have been analyzed by the fluorescent in situ hybridization with the Xcen and Y-chromosome specific painting probes. The fraction of X- and Y-bearing sperm was close to the 1:1 ratio in the Modicana breed, whereas in the Agerolese the Y-fraction was significantly higher (P < 0.002) compared to the X-counterpart. The mean rates of X-Y aneuploidy were 0.510 and 0.466%, respectively, in the two breeds; no significant differences were found among individual bulls within each breed. Average frequencies of disomic and diploid sperm were 0.425 and 0.085% in the former and 0.380 and 0.086% in the latter. In both breeds, (a) disomy was significantly more frequent than diploidy (P < 0.01), (b) YY disomy was significantly (P < 0.001) more frequent than XY or XX; (c) MI errors (XY disomy) were significantly (P < 0.01) less represented than MII (XX + YY disomy). Compared to the dairy (Italian Friesian and Brown) and meat (Podolian and Maremmana) breeds previously analyzed, the "minor" breeds investigated in the present study showed a significantly (P < 0.002) higher rate of X-Y aneuploidy (0.486 vs. 0.159 and 0.190%, respectively). Considering all the breeds analyzed -so far- and assuming no significant interchromosomal effect, the baseline level of aneuploidy in the sperm population of the species Bos taurus was estimated as 5.19%. Establishing the baseline level of aneuploidy in the sperm population of the various livestock species/breeds engaged in animal production could reveal useful for monitoring future trends of their reproductive health, especially in relation to management errors and/or environmental hazards.

Similar rates of chromosomal aberrant secondary oocytes in two indigenous cattle (Bos taurus) breeds as determined by dual-color FISH

In vitro-matured metaphase II (MII) oocytes with corresponding first polar bodies (I pb) from two indigenous cattle (Bos taurus) breeds have been investigated to provide specific data upon the incidence of aneuploidy. A total of 165 and 140 in vitro-matured MII oocytes of the Podolian (PO) and Maremmana (MA) breeds, respectively, were analyzed by fluorescence in situ hybridization using Xcen and five chromosome-specific painting probes. Oocytes with unreduced chromosome number were 13.3% and 6.4% in the two breeds, respectively, averaging 10.2%. In the PO, out of 100 MII oocytes + I pb analyzed, two oocytes were nullisomic for chromosome 5 (2.0%) and one disomic for the same chromosome (1.0%). In the MA, out of 100 MII oocytes + I pb, one oocyte was found nullisomic for chromosome 5 (1.0%) and one was disomic for the X chromosome (1.0%). Out of 200 MII oocytes + I pb, the mean rate of aneuploidy (nullisomy + disomy) for the two chromosomes scored was 2.5%, of which 1.5% was due to nullisomy and 1.0% due to disomy. By averaging these data with those previously reported on dairy cattle, the overall incidence of aneuploidy in cattle, as a species, was 2.25%, of which 1.25% was due to nullisomy and 1.0% due to disomy. The results so far achieved indicate similar rates of aneuploidy among the four cattle breeds investigated. Interspecific comparison between cattle (Xcen-5 probes) and pig (Sus scrofa domestica) (1-10 probes) also reveal similar rates. Further studies are needed that use more probes to investigate the interchromosomal effect. Establishing a baseline level of aneuploidy for each species/breed could also be useful for improving the in vitro production of embryos destined to the embryo transfer industry as well as for monitoring future trends of the reproductive health of domestic animals in relation to management errors and/or environmental hazards.

Peritoneal washing cytology in gastric cancer. How, when and who will get a benefit? A review

The most frequent cause of treatment failure following surgery for gastric cancer is peritoneal metastasis. The ability to predict the likelihood of peritoneal recurrence should improve the therapeutic approach to gastric cancer. Cytological analysis of peritoneal washings is thought to be useful for direct detection of free cancer cells in the peritoneal cavity. Intraperitoneal free cancer cells (IFCC) isolated during peritoneal washing in patients with gastric cancer, have been demonstrated to be significantly and independently related to the prognosis, influencing both early recurrence and poor survival, so that since 1998 the Japanese Classification of Gastric Carcinoma (JCGC) recommend peritoneal wash cytology (PWC) for the local staging. In Western countries PWC is not uniform practice, because of several controversies regarding the low sensitivity rate of conventional cytology, the correct application of molecular diagnosis (immunostaining and RT_PCR) and the exact role of PWC in the clinical practice. The authors examine the current apply of peritoneal washing in gastric cancer, emphasizing the clinical implication of peritoneal cytology by analyzing the different modality and techniques to perform it (conventional cytology, immunocytochemistry, RT-PCR), when to achieve it during the diagnostic or clinical work-up (at the staging or during the surgical treatment), and who will get a benefit (all patients or selected patients).

Sequence analysis and genetic variability of stearoyl CoA desaturase (SCD) gene in the Italian Mediterranean river buffalo

Stearoyl-CoA desaturase (SCD) plays a key metabolic role by changing the saturated FA content of ruminant milk and meat. In this study we characterized for the first time the stearoyl-CoA desaturase (SCD) gene in river buffalo (Bubalus bubalis) and investigated its genetic variability. On a total of 78 buffaloes, 15 SNPs were detected and 6 of them were preliminarily genotyped. In particular, the g.133A>C SNP was found to create a new consensus site for the SP1 binding site, thus generating a new tandem repeat in the promoter region. A preliminary association study with the milk fatty acid content showed that the C allele significantly affects the total desaturation index (P<0.01). Linkage disequilibrium analysis allowed identification of 7 haplotypes and 4 tag SNPs. Such polymorphisms could represent useful genetic markers for association studies with fatty acid composition, but further studies are needed to evaluate their potential use to improve the nutritional quality of the dairy products.

Peritoneal wash cytology in gastric carcinoma. Prognostic significance and therapeutic consequences

BACKGROUND AND AIMS

The prognosis of patients with gastric cancer is poor, even following curative resection, and is related primarily to the extent of disease at presentation. In locally advanced gastric tumors, peritoneal lavage cytology (PLC) is a relevant prognostic factor. The Authors present their results of peritoneal washing cytology, evaluating the prognostic value of this technique, and discussing the clinical impact.

PATIENTS AND METHODS

From July 2003 to May 2008, results of PLC in 64 patients with histologically proven primary gastric adenocarcinomas were analyzed. At laparotomy the abdomen was irrigated with 200 ml of normal saline, and ≥50 ml were aspirated and examined by means of cytology and immunocytopathology.

RESULTS

PLC was positive in 7 cases (11%). Overall, 86% of patients with a positive PLC had a pT3/pT4 tumor and 100% with a positive PLC had an N-positive tumor (p < 0.001); 71% of patients with a positive PLC had a grade G3/G4 tumor (p = 0.001). At a median follow-up of 32 months, the cumulative 5-year survival was 28%. The median survival of patients presenting positive PLC (19 months) was significantly lower than that of patients with negative peritoneal cytology (38 months) (p = 0.0001). Multivariate analysis identified cytology as a significant predictor of outcome (p = 0.018).

CONCLUSIONS

Results in the present series demonstrated that patients with a positive peritoneal cytology had advanced disease and poor prognosis, thus indicating that patients with locally advanced gastric cancer should undergo staging laparoscopy and PLC examination in order to select those requiring more aggressive treatment. Future therapeutic strategies should include PLC examination in preoperative staging, in order to select patients for more aggressive treatment.

X-Y sperm aneuploidy in 2 cattle (Bos taurus) breeds as determined by dual color fluorescent in situ hybridization (FISH)

The present study was undertaken to investigate aneuploidy rates in the sperm populations of 2 cattle (Bos taurus) breeds by using dual color fluorescent in situ hybridization (FISH) with Xcen and Y chromosome-specific painting probes, obtained by chromosome microdissection and DOP-PCR. Frozen semen from 10 Italian Friesian and 10 Italian Brown testing bulls was used for the investigation. For each bull, more than 5,000 sperm were analyzed, for a total of 52,586 and 51,342 sperm cells for the 2 breeds, respectively. The present study revealed - in both breeds - a preponderance of the Y-bearing sperm compared to the X-bearing sperm. Within each breed, a statistically significant variation in the various classes of aneuploidy (XX, YY and XY) was found: differences were found in the Friesian breed among the 3 diploidy classes, and in the Brown breed, among the 3 disomy classes (p < 0.05) as well as among the 3 diploidy classes (p < 0.01). However, the 2 breeds did not differ significantly in the overall mean rates of X-Y aneuploidy (disomy + diploidy) which amounts to 0.162% in the Italian Friesian and 0.142% in the Italian Brown. When meiosis I (MI) and II (MII) errors were compared, statistically significant differences (p < 0.01) were found in the disomy classes and in both breeds, whereas the differences between diploidy classes were not significant. Compared to humans, a lower level of aneuploidy has been found in the domestic species analyzed so far. The present study contributes to the establishment of a baseline level of aneuploidy in the sperm populations of 2 cattle breeds which could be used for monitoring future trends of reproductive health, especially in relation to environmental changes and mutagens.

[Teaching in the operative room: the benefit of daysurgery on surgical trainees]

AIM

Aim of the study was to evaluate the operative time and the incidence of post-operative complications in a group of patients undergoing Lichtenstein inguinal hernia repair performed either by surgical residents or senior surgeons in a day-surgery setting.

PATIENTS AND METHODS

The study population consisted of 198 patients: group I (n=102), in which the operator was a senior surgeon, group II (n=96), in which the operator was a resident supervised by a senior surgeon. We recorded the duration of the operation and the complications following the procedure, and statistically compared them between group I and II.

RESULTS

Our analysis showed that there was a statistically significant difference between the two groups only for the mean operative time, being shorter in group I (62 vs 82 min, p>0.05), while no significant difference was found for the incidence of complications.

CONCLUSION

In conclusion, the day-surgery setting allows a high quality training of young surgeons, based on performing minor surgical procedures such has inguinal hernia repair. This training allows a step by step supervised learning process that does not jeopardize the efficacy of the treatment as well as the patient safety. The major cost due to the increase in operative time should be considered as an investment in young surgeons education.

Chromosomal expression and localization of aphidicolin-induced fragile sites in the standard karyotype of river buffalo (Bubalus bubalis)

The present study reports on the chromosomal expression and localization of aphidicolin-induced fragile sites in the standard karyotype of river buffalo (Bubalus bubalis, 2n = 50) with the aim of establishing a 'fragile site map' of the species. Totally, 400 aphidicolin-induced breakages were analyzed from eight young and clinically healthy animals, four males and four females; these breakages were localized in 106 RBG-negative chromosome bands or at the band-interband regions. The number of breakages per chromosome did not vary statistically 'among' the animals investigated but the differences among individual chromosomes were highly significant thus indicating that the chromosomal distribution of the breakages is not random and appears only partially related to chromosome length. Fragile sites were statistically determined as those chromosomal bands showing three or more breakages. In the river buffalo karyotype, 51 fragile sites were detected and localized on the standardized ideogram of the species. The most fragile bands were as follows: 9q213 with 24 breakages out of 400; 19q21 with 16, 17q21 and inacXq24 with 15, 15q23 with 13 and 13q23 with 12 breaks, respectively. Previous gene mapping analysis in this species has revealed that the closest loci to these fragile sites contain genes such as RASA1 and CAST (9q214), NPR3 and C9 (19q19), PLP and BTK (Xq24-q25), OarCP09 (15q24), and EDNRB (13q22) whose mutations are responsible for severe phenotypic malformations and immunodeficiency in humans as well as in mice and meat quality in pigs. Further cytogenetic and molecular studies are needed to fully exploit the biological significance of the fragile sites in karyotype evolution of domestic animals and their relationships with productive and reproductive efficiency of livestock.

Characterization of two new alleles at the goat CSN1S2 locus

Two novel alleles at the goat CSN1S2 locus have been identified: CSN1S2(F) and CSN1S2(D). Sequence analyses revealed that the CSN1S2(F) allele is characterized by a G --> A transition at the 13th nucleotide in exon 3 changing the seventh amino acid of the mature protein from Val to Ile. The CSN1S2(D) allele, apparently associated with a decreased synthesis of alpha s2-casein, is characterized by a 106-bp deletion, involving the last 11 bp of the exon 11 and the first 95 bp of the following intron. Methods (PCR-RFLP and PCR) for identification of carriers of these alleles have been developed.

An allele associated with a non-detectable amount of alpha s2 casein in goat milk

The goat CSN1S2 locus is characterized by the presence of three alleles, A, B and C, all associated with about 2.5 g/l of protein per allele. The SDS-PAGE analysis of 441 individual milk samples obtained from goats belonging to a population reared in Southern Italy showed that the milk produced by three goats did not apparently contain alpha s2-casein, whereas milk produced by 37 goats showed a less intense electrophoretic band of this casein fraction (about 50%). These results can be explained by hypothesizing the presence of another allele at this locus, CSN1S2o, associated with a 'null' content of alpha s2-casein. Southern blot, PCR and PCR-RFLP analyses of the DNA region containing the CSN1S2 gene of individuals producing milk with and without alpha s2-casein did not show differences between the two groups. As a consequence, goats producing milk without alpha s2-casein carry an apparently intact gene. The first results obtained by sequencing part of the CSN1S2o allele revealed a G-->A transition at nucleotide 80 of the 11th exon which creates a stop codon and could be responsible for the absence of the alpha s2-casein in goat milk. This mutation eliminates a NcoI restriction site. A test based on this polymorphism has been established in order to identify carriers of the CSN1S2o allele.

Solution structure of an artificial Fe8S8 ferredoxin: the D13C variant of Bacillus schlegelii Fe7S8 ferredoxin

The solution structure of the D13C variant of the thermostable Fe7S8 ferredoxin from Bacillus schlegelii has been determined by 1H-NMR spectroscopy in its oxidized form. In a variable-temperature NMR study the D13C variant was as thermostable (up to 90 degrees C) as the wild-type protein (WT). Seventy-five out of 77 amino acid residues and 81% of all theoretically expected proton resonances in the D13C Fe8S8 protein have been assigned. Its structure was determined through torsion angle dynamics calculations with the program DYANA, using 935 meaningful NOEs (from a total of 1251), hydrogen bond constraints, and NMR-derived dihedral angle constraints for the cluster-ligating cysteines. Afterwards, restrained energy minimization and restrained molecular dynamics were applied to each conformer of the family. The final family of 20 structures has RMSD values from the mean structure of 0.055 nm for the backbone atoms and of 0.099 nm for all heavy atoms. The overall folding of the WT is maintained in the mutant, except for the immediate vicinity of the new cysteine, which becomes much more similar to native Fe8S8 proteins. The two residues at positions 11 and 12, which constitute an insertion with respect to all known Fe8S8 proteins, assume a conformation that does not prevent the preceding and following residues from folding like in native Fe8S8 proteins. Clear evidence for the existence of two conformations involving almost half of the amino acid residues was found. The two conformations are structurally indistinguishable. Temperature-dependent NMR experiments show that one of them is thermodynamically more stable than the other.

[Correction by physiotherapy of immune disorders in high-grade athletes]

It is well known that during intense training and competitions athletes show a remarkable reduction of their immunological responses. As a matter of fact, during these periods athletes very frequently (five to ten times more than average) fall ill. In order to correct this situation, in the USSR immunomodulator drugs are used together with high frequency electromagnetic waves which are applied on the body surface corresponding to the adrenal glands. In this way body desensitisation is accelerated. One hundred high-level athletes received an application of electromagnetic waves on the body surface corresponding to the thyroid gland and thymus, so as to lower glucocorticoid activity and activate lymphoid tissue. Indices of immunologic reactivity and hormonal levels after electromagnetic treatment were measured in all athletes.

[Effects of short-wave therapy in patients with chronic pyelonephritis]

One hundred and twenty patients (64 men and 56 women, aged 19 to 63) with chronic pyelonephritis were subdivided into two groups: a control group of 30 subjects and an experimental one of 90 subjects. Experimental subjects underwent short wave therapy (460 MHz, 50-60 W, for 8-20 minutes) in the lumbar area. Lumbosacral pain disappeared in 87 out of 90, subjects, intercostal pain in 20 out of 28, headache mitigated in 40 out of 53, asthenia was markedly reduced in 49 out of 50. Systolic and diastolic hypertension was reduced, as well as the Kakorski-Addis count in urine. Diurnal diuresis and lysozyme increased, while IgG, IgA and IgM were reduced.