High calcium diet improves the liver oxidative stress and microsteatosis in adult obese rats that were overfed during lactation.

Obesity is related to diabetes, higher oxidative stress and nonalcoholic fatty liver disease, and dietetic therapies, for instance calcium-rich diet, can improve these dysfunctions. Rats raised in small litters (SL) had increased fat depots and insulin resistance at adulthood associated with higher liver oxidative stress and microsteatosis. Thus, we evaluated if dietary calcium can improve these changes. In PN3, litter size was adjusted to 3 pups (SL group) to induce overfeeding, while controls had 10 pups until weaning. At PN120, SL group was randomly divided into: rats fed with standard chow or fed with calcium supplementation (SL-Ca group, 10 g/kg chow) for 60 days. At PN180, dietary calcium normalized food consumption, visceral fat, plasma aspartate aminotransferase (AST) and glycaemia. Concerning oxidative balance, calcium restored both higher hepatic lipid peroxidation and protein carbonylation as well as higher plasma lipid peroxidation. Higher fatty acid synthase (FAS) content, steatosis and lower protein kinase B (Akt) in SL group were normalized by dietary calcium and SL-Ca rats had lower hepatic cholesterol. Thus, calcium supplementation improved the insulin sensitivity, redox balance and steatosis in the liver. Therefore, dietary calcium can be a promising therapy for liver disease in the metabolic syndrome.

Effect of Early Overfeeding on Palatable Food Preference and Brain Dopaminergic Reward System at Adulthood: Role of Calcium Supplementation.

Rats raised in small litters (SL) are obese and hyperphagic. In the present study, we evaluated whether obesity is associated with changes in the mesocorticolimbic dopaminergic reward system in these animals at adulthood. We also assessed the anti-obesity effects of dietary calcium supplementation. To induce early overfeeding, litters were adjusted to three pups on postnatal day (PN)3 (SL group). Control litters were kept with 10 pups each until weaning (NL group). On PN120, SL animals were subdivided into two groups: SL (standard diet) and SL-Ca [SL with calcium supplementation (10 g calcium carbonate/kg rat chow) for 60 days]. On PN175, animals were subjected to a food challenge: animals could choose between a high-fat (HFD) or a high-sugar diet (HSD). Food intake was recorded after 30 min and 12 h. Euthanasia occurred on PN180. SL rats had higher food intake, body mass and central adiposity. Sixty days of dietary calcium supplementation (SL-Ca) prevented these changes. Only SL animals preferred the HFD at 12 h. Both SL groups had lower tyrosine hydroxylase content in the ventral tegmental area, lower dopaminergic transporter content in the nucleus accumbens, and higher type 2 dopamine receptor (D2R) content in the hypothalamic arcuate nucleus (ARC). They also had higher neuropeptide Y (NPY) and lower pro-opiomelanocortin contents in the ARC. Calcium treatment normalised only D2R and NPY contents. Precocious obesity induces long-term effects in the brain dopaminergic system, which can be associated with an increased preference for fat at adulthood. Calcium treatment prevents this last alteration, partially through its actions on ARC D2R and NPY proteins.

Flaxseed bioactive compounds change milk, hormonal and biochemical parameters of dams and offspring during lactation.

We evaluated maternal intake of SDG (secoisolariciresinol diglucoside), a compound from flaxseed, and flaxseed oil+SDG on biochemical and hormonal parameters of dams and male and female offspring during lactation. Dams were fed a standard diet (C); diet added 40 mg of SDG/100g diet (SDG) or diet added 40 mg of SDG/100g diet and 7% of flaxseed oil (OLSDG). SDG and OLSDG dams showed hyperprolactinemia. The OLSDG milk had lower lactose and protein, while the SDG milk had lower protein on the 14th day of lactation. At 14 days, OLSDG male and female pups showed lower body mass, SDG and OLSDG male pups had hypoprolactinemia and lower body fat mass, but higher visceral fat mass (VFM) and hypertriglyceridemia. At 21 days, male SDG and OLSDG presented hypotriglyceridemia. At 14 days, SDG and OLSDG female offspring showed higher serum 17-ß estradiol (E2); OLSDG presented hypercholesterolemia and SDG presented hypertriglyceridemia. At 21 days, SDG and OLSDG female pups showed hypotriglyceridemia and OLSDG shower lower E2. Both maternal treatments changes maternal metabolism as well as hormonal and biochemical parameters of the offspring, which are gender-dependent. Maternal hyperprolactinemia may act as an imprint factor responsible for the hormonal and metabolic changes observed in the pups.

Analysis of polymorphisms of TNF-α, LT-α, IL-10, IL-12 and CTLA-4 in patients with warm autoimmune haemolytic anaemia.

INTRODUCTION: Autoimmune haemolytic anaemia (AIHA) is defined as the increased destruction of red blood cells (RBCs) in the presence of anti-RBC autoantibodies and/or complement. Its pathogenesis is multifactorial and includes changes in mechanisms of cytokine production and functionality. A number of recent studies have implicated cytokines polymorphisms in the pathogenesis of autoimmune diseases. The aim of this study was to determine the frequency of polymorphisms of tumour necrosis factor alpha (TNF-α), lymphotoxin-α (LT-α), interleukin 10 (IL-10), interleukin 12 (IL-12) and cytotoxic T-lymphocyte antigen-4 (CTLA-4) in patients with AIHA in comparison with healthy individuals. METHODS: The study population consisted of 17 patients with AIHA and 40 healthy controls. The polymorphisms for TNF-α-308, LT-α +252, IL-10 -592, IL-12 +1188 and CTLA-4 +49 were examined by polymerase chain reaction followed by specific restriction enzyme digestion. RESULTS: There was no significant difference in the phenotypic distributions of polymorphisms of the TNF-α, IL-10, IL-12 and CTLA-4 between the patients and controls. Compared with healthy controls, patients with AIHA had a significant higher frequency of LT-α (+252) AG phenotype (41%vs. 13%; P = 0.032). CONCLUSION: In this study, no significant differences on the frequency of TNF-α, IL-10, IL-12 and CTLA-4 polymorphisms between patients with AIHA and controls was found, suggesting that the targeted polymorphisms do not influence on the emergence and evolution of the disease. However, the LT-α +252 polymorphism might have an effect for AIHAI development, suggesting that further studies are necessary to clear up this question.

Maternal flaxseed diet during lactation programs thyroid hormones metabolism and action in the male adult offspring in rats.

Flaxseed has several benefits for health such as improvement in lipid profile; and since thyroid hormones increases cholesterol biliary excretion, we decide to evaluate the programming effect of maternal flaxseed diet during lactation upon thyroid hormone metabolism and action in the adult offspring in rats. At birth, lactating rats were divided into: flaxseed dams (F) - diet with 25% of flaxseed - and controls dams (C). F and C pups received normal diet after weaning and male offspring were sacrificed at 21 and 180 days old. We evaluated serum T3, T4, and TSH; type 1 and 2 deiodinase activities (D1 and D2) in the liver, thyroid, brown adipose tissue (BAT), and pituitary; thyroid hormone receptor (TRß1) expression and mitochondrial glycerophosphate-dehydrogenase activity (GPDm) in the liver. F offspring showed lower T3 levels at weaning (-30%, p<0.05) probably caused by lower liver D1 activity (-32%, p<0.05) and higher TSH levels (+84.6%, p<0.05) characterizing a profile of hypothyroidism. At 180 days old, F offspring had lower T4 and thyroid D1 and D2 activities (-28.3%, -18.5%, and -44.2%, respectively, p<0.05) and higher BAT D2 activity (+34.5%, p<0.05). We suggest that adult F animals present an inappropriate TSH action on the thyroid, since thyroid deiodinase was lower. Serum T3 was normal probably due to a higher BAT D2 activity and may reflect the tissue T3 concentration because liver D1, TRß1, and GPDm were normal. Thus, maternal flaxseed diet during lactation may affect the thyroid hormones metabolism in a long-term.

Leptin treatment during lactation programs leptin synthesis, intermediate metabolism, and liver microsteatosis in adult rats.

Epidemiological and experimental studies have associated development of metabolic syndrome with stressful events (nutritional, hormonal, or environmental) in early life. This phenomenon is known as programing and changes in adipokines levels in early life, especially leptin, seem to be involved with its development. We have shown that neonatal hyperleptinemia on lactation programs for leptin resistance, hyperthyroidism, and higher corticosterone and catecholamines levels with cardiovascular consequences. In the present study, we evaluated the effect of hyperleptinemia during lactation on the glucose and lipid metabolism and liver morphology of adult rats, which were saline or leptin-treated (8 microg/100 g of body weight) daily, for the first 10 days of life. Leptin group had lower body mass during treatment, but higher body mass and hyperleptinemia at adulthood, without difference in fat mass. We showed that the probable source of hyperleptinemia is the higher leptin content in the subcutaneous adipose tissue. The programed rats showed hyperinsulinemia and hypoadiponectinemia with higher expression of the hypothalamic Suppressor of Cytokine Signaling 3 (SOCS3), suggesting insulin resistance. Besides, they presented higher liver glycogen and hypertriglyceridemia. We also observed liver microsteatosis in the leptin-programed adult rats. Our data show that neonatal hyperleptinemia alters glucose metabolism, which seems to be partially compensated by the hyperinsulinemia. However, changes in the lipid metabolism are not compensated. It is probable that these changes induced by neonatal hyperleptinemia result from a selective tissue specific resistance both to insulin and leptin at adulthood, and the increase of SOCS3 may play an important role in this process.

Maternal flaxseed diet during lactation alters milk composition and programs the offspring body composition, lipid profile and sexual function.

We evaluated the effects of maternal dietary flaxseed during lactation on milk composition, body composition and sexual function of the adult female offspring. The dams were fed a control casein diet (C) or flaxseed diet (F, 25%) throughout lactation. F mothers showed higher serum 17beta-estradiol (E2) and leptin at weaning. F mother's milk had lower total cholesterol (TC) and higher E2 and leptin. The offspring of F dams showed lower body mass (BM), body fat mass (BFM), visceral fat mass (VFM), TC and triglycerides (TG) and higher serum leptin and E2 at 21 days. F offspring showed delayed puberty onset. At 150 days, these offspring presented higher BFM, VFM, TC, TG, E2 and lower relative uterine weight and lower progesterone. In conclusion, flaxseed during lactation did affect the lipid profile, adipose tissue and sexual function in adulthood, probably due hyperestrogenism and hyperleptinemia at weaning.

Site of intrauterine artificial insemination in the bitch does not affect sperm distribution within the uterus.

The aim of this study was to evaluate the distribution of frozen-thawed spermatozoa within the uterine lumen and oviducts following intrauterine laparoscopic deposition at two sites. Twelve bitches of unknown reproductive history were randomly distributed into two groups. Semen (3 ml containing 300 × 10(6) frozen-thawed spermatozoa) was infused at the uterine body (UB group) or at the cranial tip of the left uterine horn. A 22-G catheter was used to access the uterine lumen. Sperm cell distribution was evaluated after ovariohysterectomy performed 3 h after artificial insemination (AI). There was no difference between groups in mean time to perform AI. Spermatozoa were detected in all uterine segments, including the tip of both horns, but none was detected in the oviduct. The 22-G catheter facilitated deposition of semen in the uterine lumen, particularly at the UB site. Sperm cell distribution occurred evenly along both horns, independent of the site of semen deposition.

Effects of residue and antioxidant on thermo-optical properties of biodiesel.

Thermal lens (TL) spectrometry was applied to soybean biodiesel samples, in order to assess the behavior of their thermo-optical properties during the preparation before and after the washing process. The study was based on the thermal diffusivity parameter, which is highly sensitive and is related to the chemical composition of the sample. The results showed a difference of approximately 20% between the initial (unwashed) and the final (washed) steps of biodiesel production. This behavior indicates that the residue of the biodiesel production influences the thermal diffusivity value. Consequently, TL spectrometry can be a useful methodology for certifying the quality of biodiesel during production.

Analysis of polymorphism at site -174 G/C of interleukin-6 promoter region in multiple myeloma.

It is well established that interleukin-6 (IL-6) is an essential growth factor for multiple myeloma (MM) and patients with increased IL-6 levels have a poor prognosis. In healthy subjects, the presence of the C allele at a polymorphic site (-174 G/C) of the IL-6 gene is related to low IL-6 levels. In view of the potential association of this particular polymorphism with IL-6 concentration, and the relevance of IL-6 in MM pathogenesis, the objective of the present study was to investigate the prevalence of IL-6 (-174 G/C) promoter polymorphism and its association with development of MM in Brazilian individuals. We investigated the prevalence of these alleles in 52 patients and 60 healthy subjects (matched by age, sex, and race) of a Brazilian population. Thirty patients were male (42.4%), 24 (46.2%) were white and the median age at diagnosis was 58.5 years (range: 28 to 84 years). To determine the IL-6 (-174 G/C) polymorphism, molecular analysis was performed by polymerase chain reaction followed by endonuclease restriction digestion. The genotype distributions observed in the group of patients were 4% CC, 42% GC and 54% GG. The C allele frequency was 0.25. These results were similar to the control group, suggesting no impact of this polymorphism on the susceptibility to MM.

The clinical impact of MTHFR polymorphism on the vascular complications of sickle cell disease.

Sickle cell disease (SCD) is one of the most common inherited diseases in the world and the patients present notorious clinical heterogeneity. It is known that patients with SCD present activation of the blood coagulation and fibrinolytic systems, especially during vaso-occlusive crises, but also during the steady state of the disease. We determined if the presence of the factor V gene G1691A mutation (factor V Leiden), the prothrombin gene G20210A variant, and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism may be risk factors for vascular complications in individuals with SCD. We studied 53 patients with SCD (60% being women), 29 with SS (sickle cell anemia; 28 years, range: 13-52 years) and 24 with SC (sickle-hemoglobin C disease; 38.5 years, range: 17-72 years) hemoglobinopathy. Factor V Leiden, MTHFR C677T polymorphism, and prothrombin G20210A variant were identified by PCR followed by further digestion of the PCR product with specific endonucleases. The following vascular complications were recorded: stroke, retinopathy, acute thoracic syndrome, and X-ray-documented avascular necrosis. Only one patient was heterozygous for factor V Leiden (1.8%) and there was no prothrombin G20210A variant. MTHFR 677TT polymorphism was detected in 1 patient (1.8%) and the heterozygous form 677TC was observed in 18 patients (34%, 9 with SS and 9 with SC disease), a prevalence similar to that reported by others. No association was detected between the presence of the MTHFR 677T allele and other genetic modulation factors, such as alpha-thalassemia, beta-globin gene haplotype and fetal hemoglobin. The presence of the MTHFR 677T allele was associated with the occurrence of vascular complications in SCD, although this association was not significant when each complication was considered separately. In conclusion, MTHFR C677T polymorphism might be a risk factor for vascular complications in SCD.

Migraine-mimicking headache and sickle cell disease: a transcranial Doppler study.

Headache occurs in sickle cell disease (SCD), but its characteristics and frequency have not previously been studied. Our aim was to study patterns of headache in adults with SCD and to correlate its presence with blood flow velocities measured by transcranial Doppler (TCD) and with brain magnetic resonance imaging (MRI) abnormalities. We studied 56 adults with SCD. Twenty-eight patients (50%) had severe and frequent headaches. In 20 patients (35.7%) the headache met the International Headache Society criteria for migraine without aura. Patients with frequent and severe headache presented TCD velocities significantly higher than those without headache, or with milder headache. No correlation was found between headache and abnormalities in brain MRI. A migraine-mimicking headache occurs in SCD but we should not understand it as a primary headache because the blood flow abnormalities secondary to SCD detected by TCD seem to play an important role in these patients.

Polymorphism of the human platelet antigen-5 system is a risk factor for occlusive vascular complications in patients with sickle cell anemia.

BACKGROUND: Polymorphisms of platelet membrane glycoproteins such as human platelet antigen (HPA)-1b, HPA-2b, the -5T/C Kozak sequence and C807T have been described as risk factors for vascular disease. Vaso-occlusion episodes are a common feature of sickle cell anaemia (SCA), leading to complications such as stroke, acute chest syndrome, avascular head femur necrosis and priapism. Complex interactions are involved in vaso-occlusion, and activated platelets may play an important role. These data raised the question of whether platelet polymorphisms could be implicated in occlusive vascular complications (OVC) of SCA. MATERIALS AND METHODS: In this study, 97 patients with SCA were analysed in two groups: 34 patients presenting with OVC (SCA-VC) and 63 without these complications (SCA-N). The distribution of the HPA-1, -2 and -5 systems, as well as C807T dimorphism and -5T/C Kozak sequence alleles, was evaluated using DNA-based methods. RESULTS: Patients of the SCA-VC group showed a higher frequency of the HPA-5b allele (0.324) compared with those of the SCA-N group (0.111) (chi2 = 13.19, P = 0.0002). None of the other polymorphisms, isolated or associated as haplotypes, demonstrated any correlation with the development of OVC in these patients. CONCLUSIONS: The findings of this study suggest that the HPA-5b allele is a genetic risk factor for the development of OVC in patients with SCA. This allele could be explored as a target for the development of new therapeutic approaches.

Lack of association between N-ras gene mutations and clinical prognosis in Brazilian children with acute lymphoblastic leukemia.

Point mutations in codons 12, 13 and 61 of the N-ras proto-oncogene have been detected in several human malignancies. We studied 170 patients with acute lymphoblastic leukemia (ALL), treated from 1988 to 1994 according to a protocol derived from BFM-83 studies, in order to evaluate the incidence and prognostic significance of mutations in this gene in childhood ALL. DNA was extracted from bone marrow smears at diagnosis and amplified by polymerase chain reaction (PCR). After screening with SSCP, PCR products were hybridized with allele specific probes and, in some cases, cloned in a pMOS Blue T vector and sequenced. Exon 2 was also studied in 101 children. Our results showed 4% of mutations in codons 12 and 13 and 2% in exon 2. Similar to a previous report, we identified 7% of mutations among children who were studied for both exons. A new mutation in codon 64 of the N-ras gene was detected in one patient. No significant clinical differences between patients with and without mutations were detected (sex, age, leukocyte counts at diagnosis, nutritional status, and risk factor according to the BFM protocol). Children with mutations in codons 12 and 13 showed significantly higher reactivity to PAS staining on blast cells than children with a wild type N-ras gene configuration. Comparison of overall- and recurrence-free survival did not show significant difference between groups with and without mutations. Our results suggest that mutations in the ras gene are infrequent in children with ALL at diagnosis and seem to be of low prognostic value.

Acute promyelocytic leukemia: the study of t(15; 17) translocation by fluorescent in situ hybridization, reverse transcriptase-polymerase chain reaction and cytogenetic techniques

Acute promyelocytic leukemia (AML M3) is a well-defined subtype of leukemia with specific and peculiar characteristics. Immediate identification of t(15;17) or the PML/RARA gene rearrangement is fundamental for treatment. The objective of the present study was to compare fluorescent in situ hybridization (FISH), reverse transcriptase-polymerase chain reaction (RT-PCR) and karyotyping in 18 samples (12 at diagnosis and 6 after treatment) from 13 AML M3 patients. Bone marrow samples were submitted to karyotype G-banding, FISH and RT-PCR. At diagnosis, cytogenetics was successful in 10 of 12 samples, 8 with t(15;17) and 2 without. FISH was positive in 11/12 cases (one had no cells for analysis) and positivity varied from 25 to 93 per cent (mean: 56 per cent). RT-PCR was done in 6/12 cases and all were positive. Four of 8 patients with t(15;17) presented positive RT-PCR as well as 2 without metaphases. The lack of RT-PCR results in the other samples was due to poor quality RNA. When the three tests were compared at diagnosis, karyotyping presented the translocation in 80 per cent of the tested samples while FISH and RT-PCR showed the PML/RARA rearrangement in 100 per cent of them. Of 6 samples evaluated after treatment, 3 showed a normal karyotype, 1 persistence of an abnormal clone and 2 no metaphases. FISH was negative in 4 samples studied and 2 had no material for analysis. RT-PCR was positive in 4 (2 of which showed negative FISH, indicating residual disease) and negative in 2. When the three tests were compared after treatment, they showed concordance in 2 of 6 samples or, when there were not enough cells for all tests, concordance between karyotype and RT-PCR in one. At remission, RT-PCR was the most sensitive test in detecting residual disease, as expected (positive in 4/6 samples). An incidence of about 40 per cent of 5' breaks and 60 per cent of 3' breaks, i.e., bcr3 and bcr1/bcr2, respectively, was observed.

Acute promyelocytic leukemia: the study of t(15;17) translocation by fluorescent in situ hybridization, reverse transcriptase-polymerase chain reaction and cytogenetic techniques.

Acute promyelocytic leukemia (AML M3) is a well-defined subtype of leukemia with specific and peculiar characteristics. Immediate identification of t(15;17) or the PML/RARA gene rearrangement is fundamental for treatment. The objective of the present study was to compare fluorescent in situ hybridization (FISH), reverse transcriptase-polymerase chain reaction (RT-PCR) and karyotyping in 18 samples (12 at diagnosis and 6 after treatment) from 13 AML M3 patients. Bone marrow samples were submitted to karyotype G-banding, FISH and RT-PCR. At diagnosis, cytogenetics was successful in 10 of 12 samples, 8 with t(15;17) and 2 without. FISH was positive in 11/12 cases (one had no cells for analysis) and positivity varied from 25 to 93% (mean: 56%). RT-PCR was done in 6/12 cases and all were positive. Four of 8 patients with t(15;17) presented positive RT-PCR as well as 2 without metaphases. The lack of RT-PCR results in the other samples was due to poor quality RNA. When the three tests were compared at diagnosis, karyotyping presented the translocation in 80% of the tested samples while FISH and RT-PCR showed the PML/RARA rearrangement in 100% of them. Of 6 samples evaluated after treatment, 3 showed a normal karyotype, 1 persistence of an abnormal clone and 2 no metaphases. FISH was negative in 4 samples studied and 2 had no material for analysis. RT-PCR was positive in 4 (2 of which showed negative FISH, indicating residual disease) and negative in 2. When the three tests were compared after treatment, they showed concordance in 2 of 6 samples or, when there were not enough cells for all tests, concordance between karyotype and RT-PCR in one. At remission, RT-PCR was the most sensitive test in detecting residual disease, as expected (positive in 4/6 samples). An incidence of about 40% of 5' breaks and 60% of 3' breaks, i.e., bcr3 and bcr1/bcr2, respectively, was observed.

Allelic polymorphisms of human fcgamma receptor IIa and Fcgamma receptor IIIb among distinct groups in Brazil.

BACKGROUND: The FcgammaRIIA gene is expressed in two polymorphic forms, R131 and H131, which differ by the replacement of histidine by arginine at position 131. The FCGR3B (FcgammaRIIIB) gene exists in two allelic isoforms, known as FCGR3B1 (FcgammaRIIIB-NA1) and FCGR3B2 (FcgammaRIIIB-NA2), which differ in nucleotides 141, 147, 227, 277, and 349. An additional polymorphism is the SH antigen that is associated with the FCGR3B3 (FcgammaRIIIB-SH) allele. STUDY DESIGN AND METHODS: By use of a PCR with allele-specific primers, the allelic polymorphisms of FcgammaRIIA and FcgammaRIIIB were determined among 263 unrelated Brazilian subjects, including Amazon Indians (n = 92), blood donors (n = 85), and patients with sickle cell disease (SCD) (n = 86). RESULTS: Amazon Indians had a significantly higher frequency of the R131 allele than did blood donors and SCD patients (0.91 vs. 0.55 vs. 0.55; p<0.001). NA1 and NA2 gene frequencies were found to be 0.67 and 0.21 for Amazon Indians, 0.58 and 0.42 for blood donors, and 0.61 and 0.39 for SCD patients, respectively. The FcgammaRIIIB-SH allele was absent from the Amazon Indians, but 9 (10.6%) blood donors and 10 (11.6%) SCD patients expressed this allele. CONCLUSION: Overall, the data indicate that the distribution of the FcgammaRIIIB alleles is significantly different in Amazon Indians from the distribution in Brazilian blood donors or African Brazilian patients with SCD, but that it is similar to the distributions reported in Asian populations. Moreover, the distribution of the FcgammaRIIA and FcgammaRIIIB alleles among Brazilian blood donors and SCD patients is comparable to the distributions reported in whites from the United States and Europe.

Platelet alloantigen frequencies in Amazon Indians and Brazilian blood donors.

The frequencies of human platelet-specific alloantigens (HPAs) vary between different ethnic groups, and genotyping using DNA techniques has been preferred over immunophenotyping methods for population studies. Using a polymerase chain reaction with allele-specific primers (PCR-ASP) method, we determined the allelic polymorphisms of five HPA systems among 174 unrelated individuals of two different Brazilian ethnic groups including Amazon Indians (n = 95) and blood donors (n = 79). Comparison of the calculated gene frequencies of the two alleles of HPA-1, -2, -3, -4 and -5 systems for Amazon Indians and Brazilian blood donors showed that gene frequencies obtained for the two alleles of HPA-1 (P<0.001), HPA-2 (P = 0.001) and HPA-5 (P<0.001) were significantly different between the two groups of individuals. All natives tested carried the HPA-2a and the HPA-5a alleles, but the HPA-1b and HPA-4b alleles are absent from the Indian population. It was also observed that all blood donors carried the HPA-1a, HPA-4a and HPA-5a alleles. In conclusion, the present data indicate differences in the frequency of the HPA systems between Amazon Indians and Brazilian subjects who present a high rate of racial admixture. While the frequencies of the HPA-1 and HPA-5 genes seen in Amazon Indians are similar to those reported for Oriental populations, the frequencies of the HPAs alleles in Brazilian blood donors are comparable to those reported for populations in North America and Europe.

The Lebanese mutation as an important cause of familial hypercholesterolemia in Brazil.

Familial hypercholesterolemia (FH) is a common autosomal disorder that affects about one in 500 individuals in most Western populations and is caused by a defect in the low-density-lipoprotein receptor (LDLr) gene. In this report we determined the molecular basis of FH in 59 patients from 31 unrelated Brazilian families. All patients were screened for the Lebanese mutation, gross abnormalities of the LDLr gene, and the point mutation in the codon 3500 of the apolipoprotein B-100 gene. None of the 59 patients presented the apoB-3500 mutation, suggesting that familial defective ApoB-100 (FDB) is not a major cause of inherited hypercholesterolemia in Brazil. A novel 4-kb deletion in the LDLr gene, spanning from intron 12 to intron 14, was characterized in one family. Both 5' and 3' breakpoint regions were located within Alu repetitive sequences, which are probably involved in the crossing over that generated this rearrangement. The Lebanese mutation was detected in 9 of the 31 families, always associated with Arab ancestry. Two different LDLr gene haplotypes were demonstrated in association with the Lebanese mutation. Our results suggest the importance of the Lebanese mutation as a cause of FH in Brazil and by analogy the same feature may be expected in other countries with a large Arab population, such as North American and Western European countries.

The Lebanese mutation as an important cause of familial hypercholesterolemia in Brazil

Familial hypercholesterolemia (FH) is a common autosomal disorder that affects about one in 500 individuals in most Western populations and is caused by a defect in the low-density-lipoprotein receptor (LDLr) gene. In this report we determined the molecular basis of FH in 59 patients from 31 unrelated Brazilian families. All patients were screened for the Lebanese mutation, gross abnormalities of the LDLr gene, and the point mutation in the codon 3500 of the apolipoprotein B-100 gene. None of the 59 patients presented the apoB-3500 mutation, suggesting that familial defective ApoB-100 (FDB) is not a major cause of inherited hypercholesterolemia in Brazil. A novel 4-kb deletion in the LDLr gene, spanning from intron 12 to intron 14, was characterized in one family. Both 5' and 3' breakpoint regions were located within Alu repetitive sequences, which are probably involved in the crossing over that generated this rearrangement. The Lebanese mutation was detected in 9 of the 31 families, always associated with Arab ancestry. Two different LDLr gene haplotypes were demonstrated in association with the Lebanese mutation. Our results suggest the importance of the Lebanese mutation as a cause of FH in Brazil and by analogy the same feature may be expected in other countries with a large Arab population, such as North American and Western European countries.