Primary thrombophilia in Mexico IV: frequency of the Leiden, Cambridge, Hong Kong, Liverpool and HR2 haplotype polymorphisms in the factor V gene of a group of thrombophilic Mexican Mestizo patients

The activated protein C resistance (APCr) phenotype is found in around 40% of thrombophilic Mexican Mestizo individuals; since only very few display the factor V gene Leiden (Arg506Gln) mutation, it was considered of interest looking for other factor V gene mutations associated to thrombophilia: The HR2 haplotype, the factor V Cambridge (Arg306Thr), the factor V Hong Kong (Arg306Gly) and the FV Liverpool (Ile359Thr). In 39 individuals, the FV Leiden was found in 10%, the HR2 haplotype in 28%, the FV Hong Kong in 2%, whereas the FV Cambridge and FV Liverpool gene mutations were not found in any individual. In the subset of 10 patients with the APCr phenotype, the FV Leiden mutation was found only in 4 (40%) whereas the HR2 haplotype in 3 (30%); all the patients with the factor V Leiden mutation and 27% of those with the HR2 phenotype displayed the APCr phenotype. It is concluded that these polymorphisms of the factor V gene are not major contributors to the thrombophilia observed in Mexican Mestizos and that additional mutations in the FV gene should be looked for in those who display the APCr phenotype.     

Benzo(a)pyrene induces hepatic AKR1A1 mRNA expression in tilapia fish (Oreochromis niloticus)

AKR1A1 or aldehyde reductase is a member of the aldo-keto reductases superfamily that is evolutionarily conserved among species. AKR1A1 is one of the five AKRs (AKR1A1 and 1C1-1C4) implicated in the metabolic benzo(a)pyrene (BaP) activation to reactive BaP 7,8-dione. BaP is a polycyclic aromatic hydrocarbon (PAH) widely distributed in aquatic ecosystems and its metabolic activation is necessary to produce its toxic effects. Although the presence of AKR1A1 in fish has been reported, its tissue distribution in tilapia (Oreochromis niloticus) and AKR1A1 inducibility by BaP are not known yet. Moreover, cytochrome P4501A (CYP1A) mRNA expression in fish has been used as a PAH biomarker of effect. Therefore, BaP effects on AKR1A1 and CYP1A gene expressions in tilapia, a species of commercial interest, were investigated by real-time RT-PCR. A partial AKR1A1 cDNA was identified, sequenced and compared with AKR1A1 reported sequences in the GenBank DNA database. Constitutive AKR1A1 mRNA expression was detected mainly in liver, similarly to that of CYP1A. BaP exposure resulted in statistically significant AKR1A1 and CYP1A mRNA induction in liver (20- and 120-fold, respectively) at 24 h. On the other hand, ethoxyquin (EQ) was used as control inducer for AKR1A1 mRNA. Interestingly, EQ also induced CYP1A mRNA levels in tilapia liver. Our results suggest that teleost AKR1A1, in addition to CYP1A, are inducible by BaP. The mechanism of AKR1A1 induction by BaP and its role in fish susceptibility to BaP toxic effects remains to be elucidated.     

New Entamoeba group in howler monkeys (Alouatta spp.) associated with parasites of reptiles

Our knowledge of the parasite species present in wildlife hosts is incomplete. Protozoans such as amoebae of the genus Entamoeba infect a large variety of vertebrate species, including NHPs. However, traditionally, their identification has been accomplished through microscopic evaluation; therefore, amoeba species have not always been identified correctly. We searched for Entamoeba spp. using a fragment of the small subunit rDNA in free-ranging howler monkeys (Alouatta palliata and A. pigra) from southeast Mexico. One hundred fifty five samples were collected, with 46 from A. palliata and 109 from A. pigra and 8 of the total samples were positive. We detected a new clade of Entamoeba, which was separated from other described species but closer to E. insolita, as well as an unnamed sequence typically found in iguana species with low shared identity values (<90%). We designated this new clade as conditional lineage 8 (CL8) and we have shown that members of this group are not exclusive to reptiles.

     

Culture-sensitive adaptation and validation of the Community-Oriented Program for the Control of Rheumatic Diseases methodology for rheumatic disease in Latin American indigenous populations

The purpose of the study is to validate a culturally sensitive adaptation of the community-oriented program for the control of rheumatic diseases (COPCORD) methodology in several Latin American indigenous populations. The COPCORD Spanish questionnaire was translated and back-translated into seven indigenous languages: Warao, Kariña and Chaima (Venezuela), Mixteco, Maya-Yucateco and Raramuri (Mexico) and Qom (Argentina). The questionnaire was administered to almost 100 subjects in each community with the assistance of bilingual translators. Individuals with pain, stiffness or swelling in any part of the body in the previous 7 days and/or at any point in life were evaluated by physicians to confirm a diagnosis according to criteria for rheumatic diseases. Overall, individuals did not understand the use of a 0–10 visual analog scale for pain intensity and severity grading and preferred a Likert scale comprising four items for pain intensity (no pain, minimal pain, strong pain, and intense pain). They were unable to discriminate between pain intensity and pain severity, so only pain intensity was included. For validation, 702 subjects (286 male, 416 female, mean age 42.7 ± 18.3 years) were interviewed in their own language. In the last 7 days, 198 (28.2 %) subjects reported having musculoskeletal pain, and 90 (45.4 %) of these had intense pain. Compared with the physician-confirmed diagnosis, the COPCORD questionnaire had 73.8 % sensitivity, 72.9 % specificity, a positive likelihood ratio of 2.7 and area under the receiver operating characteristic curve of 0.73. The COPCORD questionnaire is a valid screening tool for rheumatic diseases in indigenous Latin American populations.     

Deletion of the betaine-GABA transporter (BGT1; slc6a12) gene does not affect seizure thresholds of adult mice

Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the mammalian brain. Once released, it is removed from the extracellular space by cellular uptake catalyzed by GABA transporter proteins. Four GABA transporters (GAT1, GAT2, GAT3 and BGT1) have been identified. Inhibition of the GAT1 by the clinically available anti-epileptic drug tiagabine has been an effective strategy for the treatment of some patients with partial seizures. Recently, the investigational drug EF1502, which inhibits both GAT1 and BGT1, was found to exert an anti-convulsant action synergistic to that of tiagabine, supposedly due to inhibition of BGT1. The present study addresses the role of BGT1 in seizure control and the effect of EF1502 by developing and exploring a new mouse line lacking exons 3-5 of the BGT1 (slc6a12) gene. The deletion of this sequence abolishes the expression of BGT1 mRNA. However, homozygous BGT1-deficient mice have normal development and show seizure susceptibility indistinguishable from that in wild-type mice in a variety of seizure threshold models including: corneal kindling, the minimal clonic and minimal tonic extension seizure threshold tests, the 6Hz seizure threshold test, and the i.v. pentylenetetrazol threshold test. We confirm that BGT1 mRNA is present in the brain, but find that the levels are several hundred times lower than those of GAT1 mRNA; possibly explaining the apparent lack of phenotype. In conclusion, the present results do not support a role for BGT1 in the control of seizure susceptibility and cannot provide a mechanistic understanding of the synergism that has been previously reported with tiagabine and EF1502.     

Spontaneous heterotopic pregnancy and fetal survival

The spontaneous heterotopic pregnancy is an unusual event. Generally the extrauterine product lost and the intrauterine present complications in different grade. The most common is the rupture and can be associated with hemodynamic unstable with risk for patient's life. The intrauterine pregnancy can be continuing to the end. We report the case of patient with spontaneous heterotopic pregnancy; the diagnosis was in the first trimester, with two products (intrauterine and in right fimbrius). The salpingectomy is doing with the extrauterine pregnancy and the patient has not complications trans or postoperative time and without complications for the intrauterine pregnancy, she continues with stricter control until to obtain a life product.     

TiBALDH as a precursor for biomimetic TiO2 synthesis: stability aspects in aqueous media

Titanium(iv) bis(ammonium lactate)dihydroxide (TiBALDH) is a commercially available reagent frequently used to synthesize TiO₂. Particularly, for the biomimetic synthesis of TiO₂, TiBALDH is the preferred precursor because it can be mixed in aqueous solutions with no apparent hydrolysis or condensation reactions. Thus, proteins or other biomolecules can be used as a template in aqueous systems for the synthesis of TiO₂ from TiBALDH. Nevertheless, there is evidence that TiBALDH is in equilibrium with TiO₂, and even, the principal structure of the complex has been suggested as [Ti₄O₄(lactate)₈]⁸⁻. Since that chemical equilibrium depends on the polarity of the solvent, in this work we explored a diversity of media to test the chemical stability of TiBALDH and its equilibrium with TiO₂ at room temperature. TiBALDH (2.078 M) contains particles of 18.6 ± 7.3 nm in size, if it is diluted with deionized water, the particles reach a size of 5.2 ± 1.7 nm, which suggest that intermolecular interactions form polymers of titanium lactate complexes reversibly, reaching equilibrium after 10 hours. Typical buffer systems were tested; TiBALDH reacted rapidly only with phosphate groups, even if the source came from DNA. Therefore, phosphate buffer must be avoided in biomineralization TiO₂ synthesis. In solutions of TiBALDH at basic pH, condensation reactions are promoted to form a gel containing anatase nanoparticles, but if the solutions are acidic, monodisperse anatase nanoparticles of ∼5 nm were observed. The results show that the commercial reagent TiBALDH contains many species of titanium lactate complexes in equilibrium with TiO₂, and it is affected by the concentration, time, pH, and several ions. This peculiar behavior must be taken into account when this precursor is used and it could be useful to develop novel synthesis routes of macrostructures with biomolecules in aqueous systems.

Factors affecting TiO₂ biomineralization using TiBALDH as precursor.