TRESK potassium channel in human T lymphoblasts

TRESK (TWIK-related spinal cord K(+)) channel, encoded by KCNK18 gene, belongs to the double-pore domain K(+) channel family and in normal conditions is expressed predominantly in the central nervous system. In our previous patch-clamp study on Jurkat T lymphoblasts we have characterized highly selective K(+) channel with pharmacological profile identical to TRESK. In the present work, the presence of KCNK18 mRNA was confirmed in T lymphoblastic cell lines (Jurkat, JCaM, H9) but not in resting peripheral blood lymphocytes of healthy donors. Positive immunostaining for TRESK was demonstrated in lymphoblastic cell lines, in germinal centers of non-tumoral lymph nodes, and in clinical samples of T acute lymphoblastic leukemias/lymphomas. Besides detection in the plasma membrane, intracellular TRESK localization was also revealed. Possible involvement of TRESK channel in lymphocyte proliferation and tumorigenesis is discussed.

Olfactomedin-like 3 (OLFML3) gene expression in baboon and human ocular tissues: cornea, lens, uvea, and retina

BACKGROUND

Olfactomedin-like is a family of polyfunctional polymeric glycoproteins. This family has at least four members. One member of this family is OLFML3, which is preferentially expressed in placenta but is also detected in other adult tissues including the liver and heart. However, its orthologous rat gene is expressed in the iris, sclera, trabecular meshwork, retina, and optic nerve.

METHODS

OLFML3 messenger amplification was performed by RT-PCR from human and baboon ocular tissues. The products were cloned and sequenced.

RESULTS

We report OLFML3 expression in human and baboon eye. The full coding DNA sequence has 1221 bp, from which an open reading frame of 406 amino acid was obtained. The baboon OLFML3 gene nucleotidic sequence has 98% and amino acidic 99% similarity with humans.

CONCLUSIONS

OLFML3 gene expression in human and baboon ocular tissues and its high similarity make the baboon a powerful model to deduce the physiological and/or metabolic function of this protein in the eye.

[Evaluation of alignment on knees through a software]

INTRODUCTION

Diseases of the musculoskeletal system are often accompanied by postural deformity or malalignment. Genu varo or genu valgo can be found in the knees. It is necessary to have a diagnostic support test for diagnosis as well as for follow-up of cases since these diseases are frequently progressive and over time have serious repercussions on patient quality of life. Objective. To evaluate a software program that processes digitalized photographs as a diagnostic test for measuring the mechanical axis in patients with genu varo and genu valgo.

MATERIALS AND METHODS

The mechanical axis in both knees was measured by means of radiography (golden standard) and by means of a software program (proposed diagnostic test) in one hundred patients. Mechanical axis was considered to be abnormal when the angle was equal to or greater than four degrees. Sensitivity, specificity, positive predictive value, and negative predictive value were determined. Interobserver variation was evaluated with kappa statistics.

RESULTS

In relation to right knee genu varo, sensitivity, specificity, positive predictive value, and negative predictivie value were 0.84, 0.87, 0.84, and 0.87, respectively, and for the left knee values were 0.86, 0.87, 0.84, and 0.89, respectively. For genu valgo in the right knee, sensitivity, specificity, positive predictive value, and negative predictive value were 0.78, 0.98, 0.95, and 0.92, respectively, and in the left knee were 0.88, 0.95, 0.88, and 0.95, respectively. Kappa value was 0.9 in the right knee and 0.8 in the left knee.

CONCLUSION

The software program (diagnostic test) was useful for diagnosing genu varo or genu valgo, representing a safe and low-cost study.

[Comparing two diagnostic methods used for breast neoplasm in a cancer centre in Colima, Mexico]

OBJECTIVE

Determining the relationship between mammography neoplasm reports and histopathological diagnosis of neoplasms.

METHODS

A descriptive cross-sectional study was carried out. Patients were included who were attending the state cancerology centre (Centro Estatal de Cancerología) in Colima, Mexico. Inclusion parameters were: females having mammography and BIRADS score of 1 or over; females having biopsy and histopathology diagnosis; females of all ages, all clinic stages having a complete clinic record. Frequency, percentages, means and standard deviations were applied for descriptive statistics. Student's t-test, the Chi square test, OR and 95 %CI were applied for inferential statistics. Differences were considered to be significant when p<0.05.

RESULTS

No relationship between a BIRADS score classified as being benign (BIRADS I-II-III) or malign (BIRADS IV-V) was found with histopathological results (benign or malign) (p=0.0666). Significant relationships by category were found in a separate analysis: category IV (OR=0.024, 95 %CI=0.005-0.11, p=0.0007) and category V (OR=40.5, 95 %CI=9.03-181.3, p=0.0002).

CONCLUSIONS

I, III and V BIRADS scores had a relationship with histopathological diagnosis, while category II and IV BIRADS scores had no relationship. However, only categories 4 and5 were statistically significant.

[Comparison of three therapeutic exercises protocols to lumbar hyperlordosis improvement in asyntomatic youths]

INTRODUCTION

One of the causes of low back pain is lumbar hyperlordosis. There are different protocols of therapeutic exercises for its correction, which do not involve all of corporal segments. A modified protocol is proposed, which involves all such segments.

OBJECTIVE

To evaluate the efficacy of proposed protocol with two established protocols for correction of lumbar hyperlordosis.

MATERIALS AND METHODS

Simple-blind clinical trial on 42 students of the Faculty of Medicine at University of Colima. The three protocols: A) Pérez-Olmedo (proposed, n = 14), B) Williams (n = 15) and C) Jeffrey Saal (n = 13) were randomly assigned. Clinical and radiological evaluations were performed. Lumbar hyperlordosis was considered when Ferguson's angle was > or = 30 degrees, measured on lateral spine x-ray pictures. During two months they underwent supervised and directed exercise sessions. The improvement in lumbar hyperlordosis correction of each protocol was compared through paired Student t-test and ANOVA.

RESULTS

Average age was 18 +/- 0.9 years. Lumbar hyperlordosis frequency was 31% (n = 15). There was not significative difference on Ferguson's angle average comparation between three treatment groups. There was lumbar hyperlordosis improvement with following percentages: group A = 60%, Group B = 16% and group C = 0%.

CONCLUSION

Protocol of therapeutic exercises proposed (Pérez-Olmedo) could be an alternative to lumbar hyperlordosis improvement in asyntomatic youhts.

Preclinical evaluation of the therapeutic effect of adenoviral vectors in human papillomavirus-dependent neoplasias

Gene therapy with adenoviral vectors can eliminate neoplasic cells through selective replication and/or through pro-apoptotic, immunogenic or suicide gene expression. However, an adenoviral vector may provide anti-cancerous effects even in the absence of replication or therapeutic gene expression. The present study evaluates the therapeutic effects caused by the administration of an adenoviral vector, alone, in HPV-dependent neoplasias (HPV-N). In vivo trials were carried out in two HPV-N mouse models. One model was immunocompetent and the other was immunodeficient. In both models, the effect of intratumoral administration of saline solution (PBS) was compared with administration of an adenoviral vector that had no replicative capacity or therapeutic gene (Ad-BGal). In the immunocompetent mice, Ad-BGal adenoviral vector administration significantly reduced tumor growth, compared with PBS. No differences were observed in the immunodeficient mice. In conclusion, the present study lends support to the use of adenoviral vectors in HPV-N treatment since they are capable of generating an antitumoral effect in immunocompetent individuals, even in the absence of a therapeutic gene or viral vector replication.

Matrix Metalloproteinase-2 Promoter Polymorphism Is Associated with Breast Cancer in a Mexican Population

BACKGROUND

Matrix metalloproteinase-2 (MMP-2) is an enzyme with proteolytic activity on matrix proteins, particularly basement membrane constituents. A single nucleotide polymorphism C>T transition at -1306 displayed a strong association with several cancers. Our study investigated whether or not the MMP-2 -1306C>T polymorphism contributed to the development of breast cancer (BC) in a Mexican population.

METHODS

90 patients with BC and 96 control subjects were analyzed to detect MMP-2 -1306C>T polymorphism.

RESULTS

The frequency of MMP-2 CC genotype was significantly higher in BC patients when compared with the control group (OR 2.15; 95% CI 1.1-4.1). MMP-2 CC genotype frequency was more pronounced in younger subjects (< or =50 years) at diagnosis (OR 2.66; 95% CI 1.04-6.96).

CONCLUSION

The data suggest that MMP-2 -1306C>T polymorphism strongly contributes to the development of BC in the population studied, especially among women 50 years old and younger.

A potent replicative delta-24 adenoviral vector driven by the promoter of human papillomavirus 16 that is highly selective for associated neoplasms

BACKGROUND

Several human epithelial neoplasms are associated with high-risk strains of human papillomavirus (HPV) such as cervical, anorectal, and other carcinomas. For some tumor types the current therapeutic tools are only palliative. Conditionally replicative adenoviruses (CRAds) are promising antineoplastic agents, which also can trigger confined antitumor effects.

METHODS

We constructed a series of CRAds driven by the upstream regulatory promoter region (URR) of an Asian-American variant of HPV-16, which contained different mutations at the E1A region (dl1015 and/or Delta24) and wild-type. All vectors were tested in vitro for viral replication and cytotoxicity. Viral DNA replication and E1A expression were also assessed by quantitative PCR. Finally, we confirmed the antitumoral efficacy of this vector in injected and non-injected xenotransplanted cervical tumors in a murine model for tumor regression and survival studies.

RESULTS

A vector denominated Ad-URR/E1ADelta24 displayed a potent cytopathic effect associated with high selectivity for HPV+ cell lines. We found that the oncolytic effect of this CRAd was comparable to Ad-wt or Ad-Delta24, but this efficacy was significantly attenuated in HPV- cell lines, an effect that was contributed by the URR promoter. Ad-URR/E1ADelta24 was very effective to control tumor growth, in both, injected and non-injected tumors generated with two different HPV+ cell lines.

CONCLUSIONS

CRAd Ad-URR/E1ADelta24 is a highly selective vector for HPV+ cell lines and tumors that preserves the oncolytic efficacy of Ad-wt and Ad-Delta24. Our preclinical data suggest that this vector may be useful and safe for the treatment of tumors induced by HPV, like cervical cancers.

[The effect of MTHFR polymorphisms, pregnancy and first intercourse on cervical cancer in a population from the Northeastern Mexico]

OBJECTIVE

To investigate the possible association among MTHFR polymorfhisms, environmental factors and cervical cancer (CC) in the Mexican population.

METHODS

Seventy patients with CC and 89 control women were questioned about clinical data and their 677 and 1298 genotypes of MTHFR gene were analized.

RESULTS

Multipregnancies (0-2 vs. > or = 3, OR 2.1), an early age of first intercourse (IVS) (17 < or = vs. > or = 18 years, OR 4.3) or both factors (OR 3.5) were significantly associated with CC. MTHFR 677, 1298 polymorphisms and their combinations were not different between cases and controls. However, a significant association between pregnancies, IVS and MTHFR polymorphisms (presence of 1298C allele or 677TT genotype) was observed. The 1298C allele plus multipregnancies and IVS < or = 17 years, or both factors, increased 4.3, 5.3, and 11.8 times the risk for CC, respectively, while 677TT genotype changed the risk 2.0, 1.9, and 4.2 times, respectively.

CONCLUSION

The 1298C allele increases the risk of CC strongly in women with multipregnancies and early age of IVS, while 677TT genotype has a lower risk without becoming a protection factor.

[Longitudinal study of three families with familial Parkinson's disease]

BACKGROUND

Familial Parkinson's is a variant of Parkinson's disease (PD) transmitted generationally with an early onset.

OBJECTIVE

Describe the clinical disease characteristics and its 18 year evolution among families in Colima presenting familial PD.

MATERIALS AND METHODS

We determined disease diagnosis, evolution and hereditary pattern. The UPDRS system was used to follow the longitudinal course of the disease. Descriptive statistics were carried out using means and percentages.

RESULTS

Three families were studied, with a total of 51 subjects aged 29 +/- 22 years spanning 4 generations. Thirty-seven percent of studied subjects displayed familial PD, with disease onset at 24 +/- 9 years of age. The highest UPDRS value was 175. Disease transmission with a dominant autosomic heredity pattern was shown. One hundred percent of first and second generation members from family number 1 displayed the disease.

CONCLUSIONS

The three families displayed early onset PD and rapid progression, coinciding with described characteristics of type 1 familial Parkinsonism (PARK1). This disease is caused by the Ala53Thr mutation of the alpha-synuclein gene.

[Viruses: an important cause of human cancer]

More than 90 years have passed since Peyton Rous reported that a tumor was transmitted between chickens like an infection disease. Currently the viruses are considered the second most important cause of cancer in humans and contribute to 10 to 20% of all cancer cases in the world, some of them being very common, like cervical and hepatocellular carcinomas. Human recognized cancer viruses include HPV, HBV, HCV, EBV, HHV-8 and HTLV-1. The knowledge of how viruses participate in the ethiopathogeny of cancer will allow fighting the disease with similar strategies than those that we use to control those infective agents now days. Great efforts are being initiated to decrease incidence of the neoplasms by preventing the initial infection or by prophylactic vaccination.

Folate levels and N(5),N(10)-methylenetetrahydrofolate reductase genotype (MTHFR) in mothers of offspring with neural tube defects: a case-control study

BACKGROUND

Neural tube defects (NTDs) have been associated with biochemical factors involved in the conversion of homocysteine to methionine as folate deficiency and the mutation 677T in the N(5),N(10)-methylenetetrahydrofolate reductase gene (MTHFR).

METHODS

A case-control study was performed to detect this mutation in 38 unrelated women with NTD deceased products and 31 mothers without antecedents of NTD offspring. All products were born in Nuevo León (northeastern Mexico) during 1997. Erythrocyte and plasmatic folate levels and the genotype of the 677 polymorphism at the MTHFR locus were analyzed in both groups.

RESULTS

Although no significant differences were found in mean blood folate levels, the percentage of women in the case group with erythrocyte folate levels <160 ng/mL was significantly higher than in the control group (75 vs. 51.2%, p <0.05). The proportion of women with plasma folate levels <3.5 ng/mL was higher in the case group (16.2 vs. 0%, p <0.01). Genotype analysis demonstrated a significantly higher proportion of 677T homozygous mothers with NTD products (39.6 vs. 9.1%, p <0.05). Allele frequencies for the 677T mutation were 0.55 and 0.36 for cases and controls, respectively. The odds ratio (OR) for having a NTD product was 6.1 (95%, CI 1.56-23.6) for homozygous 677T mothers vs. homozygous 677C and heterozygous mothers. Significantly low levels of erythrocyte folate were found in the 677C homozygous case group and in plasma folate in the 677C/677T heterozygous case mothers.

CONCLUSIONS

Our study suggests that folate deficiency and MTHFR unfavorable genotype in mothers are important risk factors for severe NTD phenotype in our population.

[677T mutation of the MTHFR gene in adenomas and colorectal cancer in a population sample from the Northeastern Mexico. Preliminary results]

INTRODUCTION

Adequate intake of folates has been associated to low prevalence of colon cancer. Methylenetetrahydrofolate reductase enzyme (MTHFR) plays an important role in folate metabolism. The role of the 677 mutation at the MTHFR gene in the risk for colorectal cancer remains controversial. A recent report established that this mutation has a high prevalence in the healthy Mexican population.

AIMS

To analyze the prevalence of 677T MTHFR mutation in patients with colorectal cancer and controls without chronic gastrointestinal disorders.

METHODS

Seventy-four colorectal cancer, 32 adenomas and 110 normal samples were analyzed. Patients and controls were matched for sex and age. For each sample, DNA isolation, PCR, and mutation detection by restriction enzyme digestion were performed to determine the allele at the 677 position in the MTHFR gene.

RESULTS

Genotype 677C/677C was found in 18.7, 20.3, and 30.9% in adenomas, cancer lesions and controls, respectively. Frequencies of the 677C/677T genotype were 59.4, 56.7, and 47.3%, in adenomas, cancer lesions, and controls, respectively. Genotype 677T/677T was found in 21.9, 23.0, and 21.8% in adenomas, cancer lesions, and controls, respectively. The odds ratio between genotypes carrying the mutation (T/T and C/T) and normal genotype (CC) was 1.81 (IC 95% 0.97-3.3), chi 2 = 3.5, p = 0.06.

CONCLUSION

Our results showed that persons who carry the 677T mutation at MTHFR locus have a tendency for an increased risk for colorectal cancer. This study supports the basic concept that low levels of folic acid contribute with the colorectal cancer pathogenesis. Our lack of statistic significance may be due to reduced sample size.

[Genetic aspects of asthma]

Asthma is a complex disease associated with bronchial hyperreactivity and atopy, making asthma a disease with a phenotype that has been clinically difficult to define. Despite intense research, prevalence of asthma remain relatively high. The key reason for the high prevalence and morbility is that the fundamental mechanisms predisposing individuals to the development of asthma are not understood. Familial aggregation observed in this pathology has prompted for the search of an involved genetic component. This task is difficult due to the complex nature of asthma. A universally accepted definition for this disease is not available, clinical expression can be modulated by environmental factors, and inheritance does not follow a clear Mendelian pattern. Establishment of more precise clinical and laboratory criteria has improved the design and interpretation of genetic studies. Twin analysis and segregation studies have demonstrated an important genetic component with a probably multifactorial pattern of inheritance. "Sib pair" studies and familial segregation analyses have shown linkage between some chromosomal regions and asthma, including chromosome 5, 6, 7, 11 and 14. The search for major genes in these chromosomal segments has been focused on loci involved in the allergic process. Among these, the loci for IL-9 and IL-13 in chromosome 5 seem to play an important role in the pathogenesis of asthma. Understanding the fundamental gene-environmental interactions in the development of asthma should lead to earlier identification of susceptible individuals and more effective approaches for disease prevention.