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The objective of this study was to determine the effect of stretching pH on technological parameters and physicochemical and texture characteristics of the pasta filata cheese Telita. A no-brine cheese-making method was used to control both melting and stretching temperatures. Six vats of cheese, each with a different stretching pH (5.2, 5.3, 5.4, 5.5, 5.6, and 5.7), were made in 2h. Cheese-making was replicated using 2 different lots of milk. Differences in stretching pH significantly affected all variables evaluated; stretching temperature and pH were positively correlated. Technological parameters showed an inverse relationship between pH and acidity and a direct relationship between melting and stretching temperature. The yield was highest as the pH increased and ranged from 11.4 to 12.9 kg of cheese/100 kg of milk. Physicochemical characteristics showed the following: moisture 48.1 to 53.5% (soft and semi-hard cheese), fat 46.3 to 54.9% (dry basis, full-fat cheese), minerals 2.8 to 3.5% (dry basis), calcium content 0.5 to 1.0% (dry basis), sodium 0.38 to 0.78% (dry basis), and whiteness index 77.2 to 84.5. Texture parameters showed that as the stretching pH increased, hardness increased, adhesiveness decreased, cohesiveness decreased, springiness increased, and chewiness increased. Samples were grouped based on principal component analysis. Group 1 contained cheeses at pH 5.2 and 5.3 and were better in terms of retention of components. Group 2 contained cheeses at pH 5.6 and 5.7. These cheeses attained the highest yields, were whitest, and presented the highest values for texture parameters except for adhesiveness and cohesiveness. The third group of cheeses at pH 5.4 and 5.5 were considered the best because they showed a good balance among all variables evaluated.

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PURPOSE: Gene expression array analysis is providing key data on the potential candidate genes and biological pathways involved in schwannoma origin and development. In this way we performed expression array studies on tumor-related genes in schwannomas. METHODS: The GE Array Q Series HS-006 (SuperArray, Bethesda, MD, USA) was used to determine the expression levels of 96 genes corresponding to 6 primary biological regulatory pathways in a series of 23 schwannomas. RESULTS: We identified 15 genes down-regulated, primarily corresponding to signal transduction functions, and 26 genes up-regulated, most frequently involving cell adhesion functions. CONCLUSIONS: In addition to the NF2 inactivation (considered as an early step), variations of other biological regulatory pathways might play a key role in schwannoma (AU)

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Identifying the molecular mechanisms responsible for the resistance of gliomas to anticancer treatments is an issue of great therapeutic interest. Δ(9)-Tetrahydrocannabinol (THC), the major active ingredient of marijuana, and other cannabinoids inhibit tumor growth in animal models of cancer, including glioma, an effect that relies, at least in part, on the stimulation of autophagy-mediated apoptosis in tumor cells. Here, by analyzing the gene expression profile of a large series of human glioma cells with different sensitivity to cannabinoid action, we have identified a subset of genes specifically associated to THC resistance. One of these genes, namely that encoding the growth factor midkine (Mdk), is directly involved in the resistance of glioma cells to cannabinoid treatment. We also show that Mdk mediates its protective effect via the anaplastic lymphoma kinase (ALK) receptor and that Mdk signaling through ALK interferes with cannabinoid-induced autophagic cell death. Furthermore, in vivo Mdk silencing or ALK pharmacological inhibition sensitizes cannabinod-resistant tumors to THC antitumoral action. Altogether, our findings identify Mdk as a pivotal factor involved in the resistance of glioma cells to THC pro-autophagic and antitumoral action, and suggest that selective targeting of the Mdk/ALK axis could help to improve the efficacy of antitumoral therapies for gliomas.

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The objective of this study was to analyze the genetic variability of milk proteins of the Carora, a shorthorned Bos taurus cattle breed in Venezuela and in other Southern American countries that is primarily used for milk production. A total of 184 individual milk samples were collected from Carora cattle in 5 herds in Venezuela. The milk protein genes alpha(s1)-casein (CN) (CSN1S1), beta-CN (CSN2), kappa-CN (CSN3), and beta-lactoglobulin (LGB) were typed at the protein level by isoelectrofocusing. It was necessary to further analyze CSN1S1 at the DNA level by a PCR-based method to distinguish CSN1S1*G from B. Increased variation was found in particular at the CSN1S1 gene, where 4 variants were identified. The predominant variant was CSN1S1*B (frequency = 0.8). The second most common CSN1S1 variant was CSN1S1*G (0.101), followed by CSN1S1*C (0.082). Moreover, a new isoelectrofocusing pattern was identified, which may result from a novel CSN1S1 variant, named CSN1S1*I, migrating at an intermediate position between CSN1S1*B and CSN1S1*C. Six cows carried the variant at the heterozygous condition. For the other loci, predominance of CSN2*A2 (0.764), CSN3*B (0.609), and LGB*B (0.592) was observed. Haplotype frequencies (AF) at the CSN1S1-CSN2-CSN3 complex were also estimated by taking association into account. Only 7 haplotypes showed AF values >0.05, accounting for a cumulative frequency of 0.944. The predominant haplotype was B-A2-B (frequency = 0.418), followed by B-A2-A (0.213). The occurrence of the G variant is at a rather high frequency, which is of interest for selection within the Carora breed because of the negative association of this variant with the synthesis of the specific protein. From a cheese-making point of view, this variant is associated with improved milk-clotting parameters but is negatively associated with cheese ripening. Thus, milk protein typing should be routinely carried out in the breed, with particular emphasis on using a DNA test to detect the CSN1S*G variant. The CSN1S*G allele is likely to have descended from the Brown Swiss, which contributed to the Carora breed and also carries this allele.

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Lingual abscess is an extremely rare entity since the discovery of antibiotics, which, despite of its seriousness, it is usually a cause of death. We describe the case of a right hemilingual abscess, diagnosed by MRI scan because of its poor symptoms. This case is unique because of it affects the hemilingual central part and free edge. We discuss the most relevant aspects of this pathology.

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El absceso lingual es una entidad extremadamente rara desde el descubrimiento de los antibioticos, que a pesar de su gravedad, no suele provocar la muerte. Describimos el caso de un absceso en borde libre de hemilengua derecha, diagnosticado por una RNM debido a que se presentó con una clínica anodina, constituyendo el único caso en la literatura que afecta a la parte central y borde libre de la hemilengua. Discutimos los aspectos más relevantes del mismo

Lingual abscess is an extremely rare entity since the discovery of antibiotics, which, despite of its seriousness, it is usually a cause of death. We describe the case of a right hemilingual abscess, diagnosed by MRI scan because of its poor symptoms. This case is unique because of it affects the hemilingual central part and free edge. We discuss the most relevant aspects of this pathology

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Antibiotics are frequently prescribed in the older person, the dosification needs special care, since the pharmacokinetic parameters changes with aging and the side effects can be different in the older person. The creatinine clearance changes and we must modify the way we prescribe such antibiotics to the elderly, calculating. The variety of antibiotics now available led us to consider this paper in which we have presented the antimicrobial agents that can be considered in the treatment of the older person. We present several groups: the penicillins, cephalosporins, monobactams, carbapenems and betalactamase inhibitors or the great betalactam group. Other trimetroprin-sulfame-thoxazole, the newer macrolides (azithromycin and clarithromycin) as well as the aminoglycosides, vancomycin, clindamycin, metroridazole. The indications and contraindications are presented and reviewed.

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Infections in the older person are common and a significant cause of morbidity and mortality. Infections of the urinary tract, skin and soft tissue infections including decubitus ulcers, antibiotics associated diarrhea and lower respiratory tract infections are particularly important in the elderly because of their frequency. While most initial antibiotic therapy is empiric, its important before treatment to try to document the etiology for better use of antibiotics. Infections of the urinary tract are frequently and potentially serious in the elderly, they must be separated from asymptomatic bacteriuria that requires no therapy. Upper and lower urinary tract infections are frequently caused by aerobic gram negative bacilli and or enterococci. Most authors prefer the use of fluoroquinolones to manage such infections. The elderly with decubitus ulcer presents a problem in management, since these are frequent polymicrobic infections in which anaerobes play an important role. The initial therapy usually involves the combination of a fluoroquinolone plus an antianaerobic agent like clindamycin. C. difficile diarrhea as frequent in nursing home residents as well as the older person with prior antibiotics. The treatment should be with metronidazole and avoid the use of vancomycin. Pneumonias in the elderly can be acquired in the community, the nursing home or during a hospitalization. The etiologic agents that predominate change from S. pneumoniae and atypicals in those from the community to an increase in gram negative pneumonia. The initial treatment as started by most authors as well as guidelines include the use of a new fluoroquinolone like gatifloxacin alone or in combination with a beta-lactamic agent like ceftriaxone. For those infections acquired in the hospital therapy with third or fourth generation cephalosporins, carbapenems, beta-lactams with betalactamase inhibitors alone or in combination with an aminoglucoside and or vancomycin if MRSA is suspected is accepted therapy

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The A673 cell line was established from a patient with a primary rhabdomyosarcoma (RMS), which is referred to in the literature either as a Ewing tumor (ET) or as RMS. Although the two tumoral types are associated with specific and well-characterized translocations, no cytogenetic report on this cell line has been published. We characterized the A673 cell line using a combination of spectral karyotyping (SKY), fluorescence in situ hybridization (FISH), and reverse transcriptase polymerase chain reaction (RT-PCR), which revealed the presence of a complex karyotype and a translocation involving chromosomes 11 and 22 and the fusion of EWS and FLI1 genes, both events being specific to ET. Neither cytogenetics nor molecular alterations specific to RMS were found.

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BACKGROUND AND OBJECTIVES: The presence of specific chromosomal translocations in acute lymphoblastic leukemias (ALL) plays an important role in determining the prognosis of the patients. Our aim is to develop a highly sensitive and specific method to screen simultaneously for the four most frequent translocations in ALL: t(9;22), t(1;19), t(4;11), t(12;21). DESIGN AND METHODS: Our approach uses a multiplex-polymerase chain reaction (PCR) method, which involves two rounds of PCR using fluorescence-labeled nested primers. The chimeric transcripts resulting from these translocations can be identified by agarose gel electrophoresis or by fluorescence analysis. To validate this method we carried out the analysis in 42 pediatric ALL samples previously studied by cytogenetic and fluorescent in situ hybridization (FISH) techniques. RESULTS: In all samples with a known translocation detected by cytogenetic or FISH techniques, the same translocation was identified by the multiplex-PCR assay. Moreover, with this method we detected rearrangements in five patients in clinical remission and in two patients at diagnosis for whom karyotypes were normal and rearrangements had not been detected. The application of this multiplex-PCR assay was also useful in cases without cytogenetic results. INTERPRETATION AND CONCLUSIONS: These results show that the multiplex-PCR method allows reliable, sensitive and rapid detection of the prognostically significant translocations in ALL. We believe that this assay combined with cytogenetic analysis should be the strategy of choice for the initial diagnostic phase of acute lymphoblastic leukemia, and that it could be used not only at diagnosis but also to follow-up these alterations in remission samples without previous controls.

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The INK4a/ARF locus encodes two different proteins involved in cell cycle control. Both molecules, p16(INK4a) and p19(ARF), inhibit cell cycle progression and have been shown to act as tumor suppressors in a variety of models. Their expression is controlled by separate promoters responding to different stimuli and they therefore show independent transcriptional regulation. We have cloned and characterized a 2.5 kb region upstream of the murine p19(ARF) gene to determine the role of DNA methylation in suppressing p19(ARF) transcription in a wide panel of murine primary T cell lymphomas. This region contains a DNA fragment with the characteristics of a CpG island similar to those described for the murine p16(INK4a) and p15(INK4b) genes. Expression of p19(ARF) is decreased in a significant number (20%) of the murine lymphomas analyzed. Overexpression of the p19(ARF) transcript is also frequent, suggesting alterations in molecules of the retinoblastoma or p53 pathways that are involved in p19(ARF) regulation. Although hypermethylation of the INK4a and INK4b promoters is frequently involved in murine lymphomas, the p19(ARF) CpG island is infrequently methylated in the murine primary lymphomas studied in this work. Since loss of p19(ARF) expression cannot be explained as the result of homozygous deletions or hypermethylation of the ARF gene, other regulatory mechanisms seem to be altered in these malignancies.

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Recent studies in our laboratory reported frequent loss of heterozygosity (LOH) on mouse chromosome 4 in T-cell lymphomas, identifying three candidate tumor suppressor regions (TLSR1-3). To determine the possible existence of other tumor suppressor gene loci on the proximal-mid part of chromosome 4 and to clarify whether the p16(INK4a) (alpha and beta) and p15(INK4b) genes are the inactivation targets of deletion at TLSR1, we have tested 73 gamma-radiation-induced T-cell lymphomas of F1 hybrid mice by LOH analysis. Frequent LOH was found at the INK4a and INK4b loci and the surrounding markers D4Mit77, D4Mit245 and D4Wsm1. In addition, we identified two distinct regions of significant allelic losses in the proximal-mid part of chromosome 4, defined by the markers D4Mit116 (TLSR4) and D4Mit21 (TLSR5). Taken together, this evidence and our previous data indicate the existence of at least five different candidate sites for tumor suppressor genes on chromosome 4, thus revealing a main role for this chromosome in the development of mouse T-cell lymphomas.

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Lymphoepitheliomas are extremely rare outside the nasopharynx. Extranasopharyngeal lymphoepithellomas may be located in the stomach or digestive tract, and only one single case of esophageal location has been found in our review. In many cases the tumor is related to Epstein-Barr virus infection. We report a case of undifferentiated carcinoma of the distal third of the esophagus in a 79 year-old man. Pathological examination of the esophagus revealed an undifferentiated carcinoma with lymphold stroma (lymphoepithelioma). In situ hybridization of the neoplastic cells was negative for Epstein-Barr virus. To our knowledge, the present case is the first documented esophageal lymphoepithelioma in Western countries.

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Congenital cystic adenomatoid malformation (CCAM) is a rare pulmonary anomaly. It is a hamartomatous lesion characterized by a cessation of normal bronchiolar maturation, resulting in overgrowth of the terminal bronchioles. There is no preference for sex or location, and usually the lesion is confined to a single lobe. CCAMs have been classified into three subtypes according to the presence of and size of the cysts. Type I lesions have large cysts (2 to 10 cm in diameter), type II have smaller cysts (< 1 cm in diameter), and type III is noncystic. There have been several reports of diminution in size of these lesions and complete regression. However, in those cases fetal hydrops was absent. In the presence of nonimmune hydrops, fetal prognosis is extremely poor without any intervention. There are only two case reports describing fetal survival without intervention when nonimmune hydrops is present. We present a case of survival of a fetus with CCAM and nonimmune hydrops diagnosed at 24 weeks' gestation.

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We present an allelotype analysis of 35 cases of non-Hodgkin lymphomas and normal pairs using four microsatellite markers that flank the region occupied by the CDKN2 gene locus at 9p21. Frequent allelic losses (LOH) were detected in B-cell lineage NHLs, including Burkitt lymphoma (33.3% of total, if we only consider high grade tumors). In five of these tumors LOH did not include the CDKN2 gene. Mutational analysis of exon 1 and 2 of CDKN2 (SSGP and sequencing of abnormal bands) revealed a nonsense mutation (Arg72Ter) in one tumor (case 10), where the second hit of the Knudson's model consisted of the elimination of the wild type allele. In view of these results, the hypothesis of two different candidate tumor suppressor gene regions around the CDKN2 locus remains an intriguing possibility.

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A wide panel of murine induced T-cell lymphomas have been analysed for p16INK4a or p15INK4b alterations. Only one gamma-radiation-induced lymphoma showed p16INK4a homozygous deletion and no other intragenic mutations were found in these INK4 genes. However, de novo methylation of the 5' CpG islands of the murine p15INK4b and p16INK4a genes was found to be highly frequent. While p16INK4a hypermethylation was found in 36% of the neutron-radiation-induced lymphomas and 15% of the gamma-radiation-induced lymphomas, de novo methylation of p15INK4b occurs in 88% and 42% of these tumors respectively, correlating with deficient expression of the corresponding mRNA and allelic losses in the p15INK4b and p16INK4a chromosome location. These data represent, to our knowledge, the first report on the significant involvement of hypermethylation of these INK4 genes in murine primary tumors. Moreover, they show the importance of allelic losses and CpG island methylation of p15INK4b gene inactivation and support a tumor suppressor role for p15INK4b in T-cell lymphomas independent of p16INK4a.

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We examined the stability of different types of DNA microsatellite markers in gamma-radiation-induced thymic lymphomas as well as normal, nontumorous tissues of F1 hybrid mice derived from the parental strains C57BL/6J, RF/J, and BALB/cJ. Surprisingly, the D4Mit12 microsatellite showed genomic instability in a significant fraction of DNAs of the (C57BL/6J x BALB/cJ) F1 hybrids with independence of the tumor phenotype. This instability was not found in the reciprocal F1 DNAs, in DNAs of the parental strains, or in DNAs of (C57BL/6J x RF/J) F1 hybrid mice. These results suggest that the instability of the D4Mit 12 microsatellite is dependent on its repeat length, the genetic background of F1 hybrids, and the maternal origin of the C57BL/6J allele.

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