Complex interactions between nicotine and resveratrol in the Drosophila melanogaster wing spot test.

Nicotine (NIC) and resveratrol (RES) are chemicals in tobacco and wine, respectively, that are widely consumed concurrently worldwide. NIC is an alkaloid known to be toxic, addictive and to produce oxidative stress, while RES is thought of as an antioxidant with putative health benefits. Oxidative stress can induce genotoxic damage, yet few studies have examined whether NIC is genotoxic in vivo. In vitro studies have shown that RES can ameliorate deleterious effects of NIC. However, RES has been reported to have both antioxidant and pro-oxidant effects, and an in vivo study reported that 0.011 mM RES was genotoxic. We used the Drosophila melanogaster wing spot test to determine whether NIC and RES, first individually and then in combination, were genotoxic and/or altered the cell division. We hypothesized that RES would modulate NIC's effects. NIC was genotoxic in the standard (ST) cross in a concentration-independent manner, but not genotoxic in the high bioactivation (HB) cross. RES was not genotoxic in either the ST or HB cross at the concentrations tested. We discovered a complex interaction between NIC and RES. Depending on concentration, RES was protective of NIC's genotoxic damage, RES had no interaction with NIC, or RES had an additive or synergistic effect, increasing NIC's genotoxic damage. Most NIC, RES, and NIC/RES combinations tested altered the cell division in the ST and HB crosses. Because we used the ST and HB crosses, we demonstrated that genotoxicity and cell division alterations were modulated by the xenobiotic metabolism. These results provide evidence of NIC's genotoxicity in vivo at specific concentrations. Moreover, NIC's genotoxicity can be modulated by its interaction with RES in a complex manner, in which their interaction can lead to either increasing NIC's damage or protecting against it.

Comparative analysis by chromosome painting of the sex chromosomes in arvicolid rodents.

Sex chromosome evolution in mammals has been extensively investigated through chromosome-painting analyses. In some rodent species from the subfamily Arvicolinae the sex chromosomes contain remarkable features such as giant size, a consequence of heterochromatic enlargement, or asynaptic behaviour during male meiosis. Here, we have made a comparative study of the sex chromosomes in 6 arvicolid species using different probes from the X and Y chromosomes of 3 species, in order to gain knowledge about intra- or interspecific preservation of euchromatic regions. Our results clearly reveal poor conservation of the euchromatic region of the Y chromosome within these species, while the euchromatin on the X chromosome is extremely well preserved. Furthermore, we detected no clear correlation between the synaptic/asynaptic behaviour of the sex chromosomes, and the presence or absence of sequence homology within their euchromatic regions. Notably, our study has shown a new relationship between the giant sex chromosomes of 2 species, Microtus agrestis and Microtus cabrerae, that is, both X and Y share a novel region of common sequences in the euchromatin that is not present in the other species analysed. This interspecific euchromatic conservation, limited to the giant sex chromosomes, could point towards a common evolutionary origin for the heterochromatic enlargement process that has characterized the evolution of the sex chromosomes in some arvicolid species.

Microdissection and chromosome painting of X and B chromosomes in the grasshopper Eyprepocnemis plorans.

The relative location of 2 repetitive DNAs, i.e. ribosomal (rDNA) and a tandemly repeated satellite DNA (satDNA), with respect to the centromere, suggested that B chromosomes in the grasshopper Eyprepocnemis plorans derived intraspecifically from the X chromosome. To test this hypothesis, we microdissected X and B chromosomes and amplified the obtained DNA by 2 different procedures, the conventional DOP-PCR method and the single-cell whole-genome amplification GenomePlex method. We then generated DNA probes to perform chromosome painting. Our results have confirmed that X and B chromosomes share many DNA sequences between them and with most of the autosomes, especially at locations where the satDNA and rDNA reside, in consistency with previous information. This supports the hypothesis of an intraspecific origin of B chromosomes in E. plorans. Nevertheless, the present results did not help to clarify whether Bs were derived from the X chromosome or else from 1 or more autosomes.

A new pericentromeric repeated DNA sequence in Microtus thomasi.

Several karyotypic forms have been previously described in populations of the vole species Microtus thomasi from Greece. In particular, the karyomorphs Microtus thomasi 'thomasi' and 'atticus' differ in X chromosome morphology, being acrocentric and subtelocentric, respectively. Furthermore, remarkable heterochromatin content variability has been described in sex chromosomes of both karyomorphs. Genomic DNA digestion with AluI allowed us to clone an 884 bp long repeated DNA sequence (Mth-Alu900) from the karyomorph M. thomasi 'atticus'. This repeated DNA is AT rich and seems to be organized mainly as a dimer of the 884-bp unit, which presents three simple repeats (CAAAT, CAGAT and CAGAC) that constitute 80% of the total unit length. This repeated DNA is exclusive to M. thomasi, since it is absent from the genome of other studied Arvicolinae species. The chromosomal location of Mth-Alu900 was analyzed on M. thomasi 'thomasi' and M. thomasi 'atticus' karyomorphs, with different sex chromosome constitution. It was mainly located on the pericentromeric heterochromatin of most autosomes and X chromosomes on both karyomorphs. Results are also discussed in relation to karyotypic and sex chromosome variations in M. thomasi. To our knowledge, Mth-Alu900 constitutes a new - the third discovered so far - pericentromeric repeated DNA sequence described in Microtus species.

Retroelements (LINEs and SINEs) in vole genomes: differential distribution in the constitutive heterochromatin.

The chromosomal distribution of mobile genetic elements is scarcely known in Arvicolinae species, but could be of relevance to understand the origin and complex evolution of the sex chromosome heterochromatin. In this work we cloned two retrotransposon sequences, L1 and SINE-B1, from the genome of Chionomys nivalis and investigated their chromosomal distribution on several arvicoline species. Our results demonstrate first that both retroelements are the most abundant repeated DNA sequences in the genome of these species. L1 elements, in most species, are highly accumulated in the sex chromosomes compared to the autosomes. This favoured L1 insertion could have played an important role in the origin of the enlarged heterochromatic blocks existing in the sex chromosomes of some Microtus species. Also, we propose that L1 accumulation on the X heterochromatin could have been the consequence of different, independent and rapid amplification processes acting in each species. SINE elements, however, were completely lacking from the constitutive heterochromatin, either in autosomes or in the heterochromatic blocks of sex chromosomes. These data could indicate that some SINE elements are incompatible with the formation of heterochromatic complexes and hence are necessarily missing from the constitutive heterochromatin.

Effect of protein restriction diet on renal function and metabolic control in patients with type 2 diabetes: a randomized clinical trial.

OBJECTIVE: To assess the effect of a low protein diet (LPD) on renal function and metabolic control in three sub-groups of patients with type 2 diabetes those with or without nephropathy. RESEARCH DESIGN AND METHODS: A randomized clinical trial was conducted on 60 patients with type 2 diabetes in primary care -19 with normoalbuminuria, 22 with microalbuminuria, and 19 with macroalbuminuria-. All patients experienced a screening phase during the 3 months, and were designated according to percentages of daily caloric intake (e.g., carbohydrates 50%, fat 30%, and 20% of protein). After this period, they were randomly assigned to receive either LPD (0.6-0.8 g/kg per day) or normal protein diet (NPD) (1.0-1.2 g/kg per day) for a period of 4 months. Twenty nine patients received LPD and 31 received NPD. Primary endpoints included measures of renal function (UAER, serum creatinine and GFR) and glycemic control (fasting glucose and glycosylated hemoglobin A1c). RESULTS: Renal function improved among patients with macroalbuminuria who received LPD: UAER decreased (1,280.7 +/- 1,139.7 to 444.4 +/- 329.8 mg/24 h; p < 0.05) and GFR increased (56.3 +/- 29.0-74.2 +/- 40.4 ml/min; p < 0.05). In normoalbuminuric and microalbuminuric patients, there were no significant changes in UAER or GFR after either diet. HbA1c decreased significantly among microalbuminuric patients on both diets (LPD, 8.2 +/- 1.6-7.2 +/- 1.8%; p < 0.05; NPD, 8.8 +/- 1.9-7.1 +/- 0.8%; p < 0.05) and among macroalbuminuric patients who received NPD (8.1 +/- 1.8-6.9 +/- 1.6%; p < 0.05). CONCLUSIONS: A moderated protein restriction diet improved the renal function in patients with type diabetes 2 and macroalbuminuria.

An experimental study for biological nitrogen removal and control strategies in a sequencing batch reactor (SBR).

The aim of this work is to present an overview about an experimental study for biological nitrogen removal implemented in a pilot-scale plant, located in the Universidad Del Norte in Barranquilla, Colombia. This plant was studied in two different periods. The first period, which was carried out in 90 days, was dedicated to study the influence of the daily variations on the influent and effluent wastewater, and prove some control routines for nitrogen removal. In the second period, which was carried out in 120 days, the removal process was optimized with the addition of acetic acid as an external carbon source, and the implementation of the final control strategy was performed based on the results of the previous period.

Sex chromosomes, sex determination, and sex-linked sequences in Microtidae.

The Arvicolidae is a widely distributed rodent group with several interesting characteristics in their sex chromosomes. Here, we summarize the actual knowledge of some of these characteristics. This mammalian group has species with abnormal sex determination systems. In fact, some species present the same karyotype in both males and females, with total absence of a Y chromosome, and hence of SRY and ZFY genes. Other species present fertile, sex-reversed XY females, generally due to mutations affecting X chromosomes. Furthermore, in Microtus oregoni males and females are gonosomic mosaic (the females are XO in the soma and XX in the germ cells, while the males are XY in the soma and OY in the germ cells). Regarding sex chromosomes, some species present enlarged (giant) sex chromosomes because of the presence of large blocks of constitutive heterochromatin, which have been demonstrated to be highly heterogeneous. Furthermore, we also consider the alterations affecting composition and localization of sex-linked genes or repeated sequences. Finally, this rodent group includes species with synaptic and asynaptic sex chromosomes. In fact, several species with asynaptic sex chromosomes have been described. It is interesting to note that within the genus Microtus both types of sex chromosomes are present.

[Ventilation in special situations. Neonatal mechanical ventilation]. / Ventilación en situaciones especiales. Ventilación mecánica neonatal.

Severe respiratory failure is a common problem in premature neonates. We review the various ventilation modes available in the neonatal intensive care unit, as well as their indications, settings, and complications.

[Advanced cancer of the rectum and pregnancy. Review of the literature apropos of a case]. / Cancer avancé du rectum et grossesse. Revue de la littérature à propos d'un cas.

The authors report a case of advanced rectal cancer in a pregnant woman of 30 years of age. It was a glandular adenocarcinoma discovered in the second trimester of pregnancy. The clinical picture was one of rectal bleeding with digestive disturbances. The patient had a caesarean operation at 29 weeks of amenorrhoea because of a change in her general state. Post-operatively palliative chemotherapy was started. The patient died on the 13th day.

[Genetic maternal-child identification with DNA]. / Identificación genética materno-infantil mediante ADN.

BACKGROUND: Classical methods for newborn identification cannot establish a true biological nexus between mother and newborn, and hence they have been widely criticized. Therefore, a pilot study on a mother-infant genetic identification program (PROIGMI) has been started in order to ensure the determination of a biological relationship between mother and newborn in cases of vaginal delivery, caesarean birth or fetal autopsies. MATERIAL AND METHOD: In the delivery room and after informed consent, a total of 100 blood samples from mother/newborn couples were taken and deposited on clean and sterile paper supports. DNA from a total of 20 mother/newborn couples was studied by PCR techniques, being able to unequivocally establish the biological relationship in all cases, even when using minimal amounts of DNA. RESULTS: Blood samples collection does not show differences regarding the kind of birth (delivery, cesarean). The protocol used is easy and fast, and does not employ materials not known for health care professionals. Minimal amounts of blood yield enough DNA to obtain conclusive inclusion probabilities. CONCLUSIONS: The use of DNA allows to stablish the so called biological truth in cases of doubt or where necessary; with the use of medical protocols these studies can be completed in 6 to 8 hours using small amounts of DNA (5 microliters).

[The current situation of adolescents with cancer in pediatric hematology-oncology units in Spain. Results of a national survey]. / Situación actual de los adolescentes con cáncer en las unidades de hemato-oncología pediátrica españolas.

Little attention was paid to adolescents with Cancer in Spain up to 2010. In 2011 an "Adolescents with Cancer Committee" was established by the Spanish Society of Pediatric Hemato-Oncology (SEHOP) to care for the needs of these patients. The aim of this national survey was to outline the present situation of adolescents with cancer in Spanish Pediatric Hemato-Oncology units. A web based survey assessed institutional management of adolescents with cancer. The survey was personally sent to one member of the staff of each Pediatric Hemato-Oncology unit in Spain. It included questions about epidemiology, management, psycho-social coverage, specific facilities, and follow up of these patients. A total of 40 institutions out of 41 responded to the survey (overall response rate 98%). Fifty-six percent of the institutions had patients over 14, but only 36% of the institutions treated patients up to 18 years old. Only 25.6% of the units have more than 40 new pediatric cases every year. The percentage of patients between 14 and 18 years of age is below 10% in most of the units (77%). In 30.8% and 48.7% of the institutions, pediatric hemato-oncologists treat adolescents with hematological and solid tumors, respectively. The rest of the patients are seen by adult oncologists. There is only one institution that has a physician specifically dedicated to adolescent patients, and only two units have a "teenager's room". Only 2 units have a psychologist specifically trained to treat adolescents with cancer. The survey shows that most adolescents with cancer in Spain between 14 and 18 years of age are treated by adult oncologists. Most pediatric institutions still do not have specific facilities and psychosocial support for adolescents. The SEHOP is working hard in order to improve the quality of cancer care, and the quality of survival of this population.

Sequence analysis and mapping of the Sry gene in species of the subfamily Arvicolinae (rodentia).

The rodent subfamily Arvicolinae, which contains about 125 species, presents some interesting exceptions concerning Sry, the sex determining gene in mammals. In some species multiple Sry copies have been described on the Y chromosome and in the Iberian vole, Microtus cabrerae, several Sry sequences have been cloned and mapped not only on the Y but also on the X chromosome. Here we present a comparative analysis of Sry sequences from a total of 22 species. Our study demonstrates for the first time that for most North American species, as previously reported for the European species, multiple copies of the Sry gene exist on the Y chromosome. Furthermore, we have sequenced and analyzed the full sequence of Sry from several European species, showing that the sequence and structure of the gene in this group of species present the main features described for Sry in other mammals. Finally, FISH analyses on some of these species demonstrated that all Sry sequences, despite their functional status, mapped on the euchromatic short arm of the Y chromosome.

Characterization of the satellite DNA Msat-160 from the species Chionomys nivalis (Rodentia, Arvicolinae).

The satellite DNA Msat-160 has been previously characterized in several species of the genus Microtus. Here we present the characterization of Msat-160 from Chionomys nivalis, a species with a very primitive karyotype. As in other Microtus species analyzed, C. nivalis Msat-160 is AT rich, has a monomer length of 160 bp, is undermethylated and is mainly located in all the pericentromeric heterochromatin of all autosomes and the X chromosome, but is completely absent from the Y chromosome. Hence, our results support the hypothesis that Msat-160 was initially distributed in the pericentromeric heterochromatin of all autosomes and the X chromosome. The taxonomic status of the genus Chionomys in relation to the genus Microtus is a very interesting issue, so we constructed phylogenetic dendrograms using Msat-160 sequences from several Microtus species. Although the results were not informative about this issue, the presence of Msat-160 in C. nivalis and Microtus species suggested that both genera are closely related and that this satellite DNA was present in the common ancestor. Studies of Msat-160 in different arvicoline species could help to determine the origin of this satellite and, perhaps, to establish the phylogenetic relationships of some arvicoline groups.

Distribution of L1-retroposons on the giant sex chromosomes of Microtus cabrerae (Arvicolidae, Rodentia): functional and evolutionary implications.

Long interspersed nuclear elements (L1 or LINE-1) are the most abundant and active retroposons in the mammalian genome. Traditionally, the bulk of L1 sequences have been explained by the 'selfish DNA' hypothesis; however, recently it has been also argued that L1s could play an important role in genome and gene organizations. The non-random chromosomal distribution of these retroelements is a striking feature considered to reflect this functionality. In the present study we have cloned and analyzed three different L1 fragments from the genome of the rodent Microtus cabrerae. In addition, we have examined the chromosomal distribution of this L1 in several species of Microtus, a very interesting group owing to the presence in some species of enlarged ('giant') sex chromosomes. Interestingly, in all species analyzed, L1-retroposons have preferentially accumulated on both the giant- and the normal-sized sex chromosomes compared with the autosomes. Also we have demonstrated that L1-retroposons are not similarly distributed among the heterochromatic blocks of the giant sex chromosomes in M. cabrerae and M. agrestis, which suggest that L1 retroposition and amplification over the sex heterochromatin have been different and independent processes in each species. Finally, we proposed that the main factors responsible for the L1 distribution on the mammalian sex chromosomes are the heterochromatic nature of the Y chromosome and the possible role of L1 sequences during the X-inactivation process.

The usefulness of stool screening for diagnosing cholelithiasis in acute pancreatitis. A description of the technique.

Screening stools for gallstones in patients with acute pancreatitis has been found to be a valuable diagnostic procedure in clinical practice. It is particularly helpful to know that a patient with pancreatitis has gallstones and, therefore, the disease is probably caused by the passage of these stones. A detailed description of the technique employed for stool screening is presented. The procedure was applied in 51 patients recovering from an attack of gallstone pancreatitis,in 51 control patients with known gallstones disease but without acute pancreatitis, and also in 10 patients with acute alcoholic pancreatitis Gallstones were found in the feces in 47 of the 51 patients with gallstone pancreatitis (92.1%), in only 6 of the 51 control cases (11.8%) (chi square = 62.84; P less than 0.0001), and in none of the 10 patients with alcoholic pancreatitis. In the group with gallstone pancreatitis, the finding occurred within 10 days after the attack. Oral cholecystography was also accomplished an average of 12.7 days after the attack in 38 of the 61 pancreatitis patients (28 with biliary and 10 with alcoholic pancreatitis). In 27 of the 28 patients with gallstone pancreatitis (96.4%) and in 4 of the 10 patients with alcoholic pancreatitis, radiologic evidence of cholelithiasis was found. There were 19 patients with gallstone pancreatitis who did not have a cholecystogram accomplished because of jaundice, recurrent pancreatitis, previous cholecystectomy, and pregnancy. These results suggest that screening stools is as accurate and reliable as cholecystography for the diagnosis of gallstones in individuals with pancreatitis. In addition, this method has three definite advantages over cholecystography: There are no contraindications; it requires no special equipment or personnel; and it can be used much earlier than cholecystography in patients recovering from an attack of acute pancreatitis. Screening stools for gallstones should be considered an elective diagnostic procedure for current clinical application.

Assessment of luteal blood flow in normal early pregnancy.

A cross-sectional study was performed in 85 low-risk singleton first trimester pregnancies to assess corpus luteum blood flow during this period. Gestational age, established by measuring crown-rump length, ranged from 6 to 12 weeks. All cases were studied by transvaginal color velocity imaging and pulsed Doppler ultrasonography. After corpus luteum blood flow was identified by color velocity imaging, the resistive index and pulsatility index were calculated to assess vascular resistance. Overall, detection rate of corpus luteum blood flow was 75.2%. No statistical differences were found in mean resistive index and pulsatility index among gestational weeks studied. Linear regression analysis showed that nonsignificant changes in resistive and pulsatility indices occur during the first weeks of normal early pregnancy (R2 = 0.0059 for resistive index, R2 = 0.0008 for pulsatility index). In conclusion, luteal blood flow is constant during normal early pregnancy.