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1.
Biomedicines ; 12(2)2024 Feb 02.
Article in English | MEDLINE | ID: mdl-38397954

ABSTRACT

BACKGROUND: Cytogenotoxic damage caused by the consumption of legal and illegal drugs in drug abusers has been demonstrated, primarily due to alterations in their antioxidant capacity, cellular repair mechanisms, and increased production of free radicals. Folic acid shows antioxidant activity by acting as a reducing agent, neutralizing present free radicals, and reducing genomic damage. METHODS: The intervention involved administering 15 mg of folic acid, divided into three doses per day, to a group of 44 drug abusers. The frequency of nuclear abnormalities (NAs) was determined; micronuclei (MNs), nuclear buds (NBUDs), binucleated cells (BNs), abnormally condensed chromatin (CC), karyorrhexis (KX), pyknotic nuclei (PNs), and karyolysis (KL) were determined at different pre-treatment (baseline) and post-treatment time points at 15 and 30 days. Additionally, a group of 44 healthy individuals was used as the control group. RESULTS: We observed a statistically significant decrease in the frequency of NAs in the drug abuser group (28.45 ± 17.74 before supplementation vs. 11.18 ± 7.42 at 15 days and 9.11 ± 10.9 at 30 days of supplementation). Specifically, it decreased the frequency of NBUDs, BNs, CC, KX, and PNs (p < 0.05). CONCLUSION: Our study demonstrates a clear improvement in cytogenotoxic damage in drug abusers supplemented with folic acid.

2.
Curr Issues Mol Biol ; 45(11): 8716-8732, 2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37998725

ABSTRACT

Type 2 diabetes (T2D) is a chronic systemic disease with a complex etiology, characterized by insulin resistance and mitochondrial dysfunction in various cell tissues. To explore this relationship, we conducted a secondary analysis of complete mtDNA sequences from 1261 T2D patients and 1105 control individuals. Our findings revealed significant associations between certain single-nucleotide polymorphisms (SNPs) and T2D. Notably, the variants m.1438A>G (rs2001030) (controls: 32 [27.6%], T2D: 84 [72.4%]; OR: 2.46; 95%CI: 1.64-3.78; p < 0.001), m.14766C>T (rs193302980) (controls: 498 [36.9%], T2D: 853 [63.1%]; OR: 2.57, 95%CI: 2.18-3.04, p < 0.001), and m.16519T>C (rs3937033) (controls: 363 [43.4%], T2D: 474 [56.6%]; OR: 1.24, 95%CI: 1.05-1.47, p = 0.012) were significantly associated with the likelihood of developing diabetes. The variant m.16189T>C (rs28693675), which has been previously documented in several studies across diverse populations, showed no association with T2D in our analysis (controls: 148 [13.39] T2D: 171 [13.56%]; OR: 1.03; 95%CI: 0.815-1.31; p = 0.83). These results provide evidence suggesting a link between specific mtDNA polymorphisms and T2D, possibly related to association rules, topological patterns, and three-dimensional conformations associated with regions where changes occur, rather than specific point mutations in the sequence.

3.
Placenta ; 135: 1-6, 2023 04.
Article in English | MEDLINE | ID: mdl-36878143

ABSTRACT

INTRODUCTION: Preeclampsia is a leading cause of maternal and fetal morbidity in low- and middle-income countries, including those in Latin America. Placental vascular alterations are crucial in the pathophysiology of preeclampsia and few studies have evaluated nucleotide variations on genes associated with vascular regulation in the human placenta. This study aimed to evaluate whether placental nucleotide variations on eNOS, VEGFA, and FLT-1 genes are more frequently associated with preeclampsia in the Latin American population. METHODS: This case-control study included placental tissue from 88 controls and 82 cases that were genotyped through Taqman probes for eNOS, VEGFA, and FLT-1 genes. The intergroup comparisons were analyzed with the Mann-Whitney U test. Genotype and allele frequencies were compared by the X2 test. The association between the nucleotide variants with preeclampsia was evaluated through logistic regression analysis. RESULTS: A significant association was observed for VEGFA SNV rs2010963 (OR 1.95; CI 95% 1.13-3.37), after adjusting for population substructure. The allele combination T, G, G, C, C, C (rs2070744, rs1799983, rs2010963, rs3025039, rs699947 and rs4769613 respectively), showed a negative association with preeclampsia (OR 0.08; CI 95% 0.01-0.93). DISCUSSION: Placental SNV rs2010963 in the VEGFA gene was a risk factor for preeclampsia, while the allele combination T, G, G, C, C, C may represent potential protective factors for preeclampsia within Latin American women.


Subject(s)
Pre-Eclampsia , Pregnant Women , Humans , Female , Pregnancy , Case-Control Studies , Latin America , Pre-Eclampsia/genetics , Polymorphism, Single Nucleotide , Placenta , Vascular Endothelial Growth Factor A/genetics
4.
Genes (Basel) ; 13(11)2022 10 27.
Article in English | MEDLINE | ID: mdl-36360199

ABSTRACT

Breast cancer has an important incidence in the worldwide female population. Although alterations in the mitochondrial genome probably play an important role in carcinogenesis, the actual evidence is ambiguous and inconclusive. Our purpose was to explore differences in mitochondrial sequences of cases with breast cancer compared with control samples from different origins. We identified 124 mtDNA sequences associated with breast cancer cases, of which 86 were complete and 38 were partial sequences. Of these 86 complete sequences, 52 belonged to patients with a confirmed diagnosis of breast cancer, and 34 sequences were obtained from healthy mammary tissue of the same patients used as controls. From the mtDNA analysis, two polymorphisms with significant statistical differences were found: m.310del (rs869289246) in 34.6% (27/78) of breast cancer cases and 61.7% (21/34) in the controls; and m.315dup (rs369786048) in 60.2% (47/78) of breast cancer cases and 38.2% (13/34) in the controls. In addition, the variant m.16519T>C (rs3937033) was found in 59% of the control sequences and 52% of the breast cancer sequences with a significant statistical difference. Polymorphic changes are evolutionarily related to the haplogroup H of Indo-European and Euro-Asiatic origins; however, they were found in all non-European breast cancers.


Subject(s)
Breast Neoplasms , Humans , Female , Breast Neoplasms/genetics , DNA, Mitochondrial/genetics , Mitochondria/genetics , Polymorphism, Genetic
5.
Complement Ther Med ; 70: 102852, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35843472

ABSTRACT

BACKGROUND: Prediabetes and type 2 Diabetes Mellitus (T2DM) are characterized by increased blood sugar concentration and insulin resistance. Although there are only a few reports of potential benefits of flaxseed's consumption on different metabolic parameters, there is no evidence of its effect among people with these conditions. OBJECTIVES: The present systematic review and meta-analysis aimed to assess the effect of flaxseed supplementation on glycemic control variables and insulin resistance in prediabetes and T2DM. METHODS: A literature search was conducted through PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science, to identify Randomized Control Trials (RCTs) that evaluated the effect of milled or ground flaxseed supplementation on fasting blood glucose, HbA1c, insulin concentrations, or HOMA-IR. The data were analyzed using Comprehensive Meta-Analysis (CMA) software version 3.3 in a fixed-effect model. RESULTS: Seven studies were included in the systematic review and the meta-analysis, the results showed a significant reduction on fasting blood sugar (SMD: -0.392, 95% CI: -0.596, -0.187, p = <0.001, I2 = 64.81%) insulin concentrations, (SMD: -0.287, 95% CI: -0.534, -0.041, p = 0.022, I2 = 32.53%), HbA1c (SMD: -0.442, 95% CI: -0.770, -0.114, p = 0.008, I2 = 11.058%), and HOMA-IR (SMD: -0.284, 95% CI: -0.530, -0.038, p = 0.024, I2 = 0.00%) after flaxseed supplementation. CONCLUSIONS: Flaxseed supplementation seems to improve glycemic control variables and insulin resistance in prediabetes and T2DM; however, more RCTs are needed to have more decisive evidence about doses, method of supplementation, and the possible effect of synergy with the dietetic treatment.


Subject(s)
Diabetes Mellitus, Type 2 , Flax , Insulin Resistance , Prediabetic State , Blood Glucose , Dietary Supplements , Glycated Hemoglobin , Glycemic Control , Humans , Insulin , Randomized Controlled Trials as Topic
6.
Genes (Basel) ; 13(5)2022 04 27.
Article in English | MEDLINE | ID: mdl-35627158

ABSTRACT

Type 2 diabetes (T2D) has been linked to the expression of Human Leukocyte Antigens, principally to the Major Histocompatibility Complex Class II, with only scarce reports of Major Histocompatibility Complex Class I in specific populations. The objective of the present work was to explore the presence of polymorphisms in the MHC Class I related to T2D in the Mexican population using the Genome-Wide Association Studies Slim Initiative in Genomic Medicine of the Americas (GWAS SIGMA) database. This database contains information on 3848 Mexican individuals with T2D and 4366 control individuals from the same population without a clinical or hereditary history of the disease. The searching criteria considered a p-value of <0.005 and an odds ratio (OR) of >1.0. Ten novel, statistically significant nucleotide variants were identified: four polymorphisms associated with HLA-A (A*03:01:01:01) and six with HLA-C (C*01:02:01:01). These alleles have a high prevalence in Latin American populations and could potentially be associated with autoimmunity mechanisms related to the development of T2D complications.


Subject(s)
Diabetes Mellitus, Type 2 , Alleles , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/genetics , Genome-Wide Association Study , HLA Antigens/genetics , Humans , Polymorphism, Single Nucleotide
7.
Front Med (Lausanne) ; 9: 795309, 2022.
Article in English | MEDLINE | ID: mdl-35252239

ABSTRACT

Preeclampsia (PE) is a leading cause of maternal-fetal mortality worldwide, and obesity is an important risk factor. Genes associated with pathophysiological events common to preeclampsia and obesity, such as PLAC8, remain to be studied; therefore, the aim of the present study was to evaluate this gene in the placentas of women affected with preeclampsia and healthy pregnant women. This case-controlled study included 71 healthy and 64 preeclampsia pregnancies. Gene expression was evaluated in primary human cytotrophoblasts (PHCT) from six normal and six preeclampsia pregnancies, and protein expression was verified in placentas from five healthy and six preeclampsia pregnancies. The whole coding and 5' regions of the PLAC8 gene were sequenced from healthy (n = 10) and preeclamptic (n = 10) pregnancies. The presence of the observed nucleotide variations was analyzed by RT-PCR in the total population. Statistical analyses were performed accordingly. Obesity was associated with severe preeclampsia (SPE) (OR = 3.34; CI 95% 1.3-8.2, p < 0.01). Significantly higher mRNA and protein expression was observed in preeclamptic vs. healthy placentas (p < 0.05). After sequencing, a single nucleotide variation was identified in 10 cases and one control (p < 0.01), which was then evaluated in the total population showing no association with preeclampsia. This preliminary study confirms the association of SPE with obesity and suggests higher expression of PLAC8 mRNA and protein in placentas from preeclampsia. No differences in nucleotide variations between cases and controls of the whole population were observed. Further research is required to evaluate the implications of higher gene/protein expression in preeclampsia and the causes of such variation.

8.
Healthcare (Basel) ; 10(3)2022 Mar 07.
Article in English | MEDLINE | ID: mdl-35326965

ABSTRACT

With the appearance of new viruses and infectious diseases (ID) such as COVID-19 in 2019, as well as the lack of specific pharmacological tools for the management of patients with severe complications or comorbidities, it is important to search for adjuvant treatments that help improve the prognosis of infectious disease patients. It is also important that these treatments limit the oxidative and hyperinflammatory damage caused as a response to pathogenic agents, since, in some cases, an inflammatory syndrome may develop that worsens the patient's prognosis. The potential benefits of complementary nutrients and dietary interventions in the treatment of pathological processes in which oxidative stress and inflammation play a fundamental role have been widely evaluated. Coenzyme Q10 (CoQ10) is a supplement that has been shown to protect cells and be effective in cardiovascular diseases and obesity. Additionally, some studies have proposed it as a possible adjuvant treatment in viral infections. Preclinical and clinical studies have shown that CoQ10 has anti-inflammatory and antioxidant effects, and effects on mitochondrial dysfunction, which have been linked to the inflammatory response.

9.
Ultrasound Med Biol ; 47(6): 1448-1464, 2021 06.
Article in English | MEDLINE | ID: mdl-33707090

ABSTRACT

The incidence of muscle spasticity is high in patients with diseases of the central nervous system. This condition leads to significant limitations in movement and impaired functional capacities. Muscle spasticity manifests as changes in the mechanical properties of the muscles. This muscle disorder is generally assessed using qualitative methods, whose validity, reliability and sensitivity are questionable. In recent years, ultrasound elastography (USE) has been used as a non-invasive technique for characterizing the stress response and mechanical properties of individual muscles in the evaluation of spasticity. This article presents a systematic review of the USE techniques, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) declaration guidelines, used for the evaluation of muscle stiffness caused by spasticity. The articles selected in this study were evaluated using the Quality Appraisal of Diagnostic Reliability (QAREL) tool. Mainly, studies on the assessment of spasticity involving the evaluation of muscle stiffness with USE techniques (i.e., shear-wave elastography [SWE] or compression elastography [CE]) were selected. Then, common topics related to the assessment of spastic muscles and the statistical results of these studies were classified. Of 21 articles, nine used only CE, 10 used only SWE and two used both techniques. In the studies, statistically significant differences were observed in the measurements of muscle stiffness between the paretic and non-paretic sides as well as between patients and healthy patients. The clinical measurements obtained, devices used and assessment and probe positions for both techniques were discussed. The most frequently studied muscles were the biceps (n = 7) and gastrocnemius (n = 11). On applying the QAREL tool, we found that only two studies showed compliance at 80%-90%, seven studies at 50%-70% and the remaining 12 at 10%-40%. The results showed that USE techniques have limitations in spasticity assessment, such as subjectivity because of the lack of standardized protocols. A deficit of studies on intra-operator and inter-operator measurements indicates that this technique is not yet mature for spasticity diagnosis, although it is a promising diagnostic tool for designing treatment plans and monitoring the effectiveness of therapeutic modalities.


Subject(s)
Elasticity Imaging Techniques , Muscle Spasticity/diagnostic imaging , Elasticity Imaging Techniques/methods , Humans
10.
J Med Food ; 24(1): 28-32, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32460589

ABSTRACT

Gymnema sylvestre, a plant typical of India, has long been known for its hypoglycemic effects. The objective of this study was to evaluate the effect of G. sylvestre administration on glycemic control, insulin secretion, and insulin sensitivity in patients with impaired glucose tolerance (IGT). A randomized, double-blind, placebo-controlled clinical trial was conducted in 30 patients with IGT. Fifteen patients randomly received G. sylvestre in doses of 300 mg b.i.d. and the other 15 received placebo in the same way. Before and after the intervention, anthropometric and metabolic measurements were taken, including 2-h oral glucose tolerance test (2-h OGTT), fasting plasma glucose, glycated hemoglobin A1c (A1C), and the lipid profile panel. Areas under the curve of glucose and insulin were calculated, as well as the insulinogenic, Stumvoll, and Matsuda indices. Wilcoxon, Mann-Whitney U, and chi-square or Fisher's exact tests were performed, and a P-value ≤.05 was considered statistically significant. There was a significant reduction in 2-h OGTT (9.1 ± 1.2 vs. 7.8 ± 1.7 mmol/L, P = .003), A1C (5.8 ± 0.3% vs. 5.4 ± 0.4%, P = .025), body weight, body mass index, and low-density lipoprotein cholesterol levels in the G. sylvestre group, with an increment in the Matsuda index (1.8 ± 0.8 vs. 2.4 ± 1.2, P = .008). At the end of the intervention, 46.7% of the patients obtained normal values in A1C. In conclusion, G. sylvestre administration in patients with IGT decreased 2-h OGTT and A1C, increasing insulin sensitivity. There were also improvements in anthropometric measures and the lipid profile.


Subject(s)
Glucose Intolerance , Gymnema sylvestre/chemistry , Insulin Resistance , Insulin Secretion , Plant Preparations/therapeutic use , Blood Glucose , Double-Blind Method , Glucose Intolerance/drug therapy , Glycemic Control , Humans , India , Insulin/metabolism , Phytotherapy
11.
Arch Womens Ment Health ; 22(4): 511-518, 2019 08.
Article in English | MEDLINE | ID: mdl-30324247

ABSTRACT

Ultrasound is a common medical care procedure during pregnancy which has psychological implications. Research has found that it reduces the mother's level of anxiety, but there is not enough literature on the effects of the ultrasound in relation to the trimester it is done (first, second, and third) and the effects on the psychosocial adaptation to pregnancy. The purpose of this study was to investigate the effects of the ultrasound in the first, second, and third trimester on anxiety and variables related to psychosocial adaptation to pregnancy. A pre-post intervention design was used. Participants were 111 pregnant women attending a prenatal diagnosis ultrasound scan procedure, State-Trait Anxiety Inventory (STAI), and Prenatal Self-Evaluation Questionnaire (PSEQ) were used to measure anxiety and psychosocial adaptation to pregnancy, respectively. Previous history was obtained through an interview. Results indicated that anxiety diminished after the ultrasound regardless of the trimester in which the ultrasound took place. However, first trimester ultrasound showed an additional benefit favoring the mother's psychosocial adaptation to pregnancy, identification with the motherhood role, and the quality of the relationship with the partner. These findings suggest that in addition to the medical value of the ultrasound, it also has an important psychological value that has to be considered in order to guarantee an integral care of the pregnant women, especially in the first trimester.


Subject(s)
Adaptation, Psychological , Anxiety/psychology , Pregnancy Trimesters , Pregnancy/psychology , Pregnant Women/psychology , Ultrasonography, Prenatal/psychology , Adult , Anxiety/epidemiology , Female , Humans , Personality Inventory , Pregnancy Complications/diagnostic imaging , Pregnancy Complications/psychology , Pregnancy Trimester, First , Pregnancy Trimester, Second , Pregnancy Trimester, Third , Spain/epidemiology
12.
J Med Food ; 21(5): 469-473, 2018 May.
Article in English | MEDLINE | ID: mdl-29261010

ABSTRACT

Chlorogenic acid has been described as a novel polyphenol with metabolic effects on glucose homeostasis. The aim of this study was to evaluate the effect of chlorogenic acid administration on glycemic control, insulin secretion, and insulin sensitivity in patients with impaired glucose tolerance (IGT). A randomized, double-blind, placebo-controlled clinical trial was performed in 30 patients with IGT; 15 patients randomly assigned to oral chlorogenic acid received 400 mg three times per day for 12 weeks, and the other 15 patients received placebo in the same way. Before and after the intervention, anthropometric and metabolic measurements, including fasting plasma glucose (FPG), glycated hemoglobin A1c, and a lipid profile, were performed. Area under the curve of glucose and insulin as well as the insulinogenic, Stumvoll, and Matsuda indices were calculated. Wilcoxon, Mann-Whitney U, and chi-square tests were performed, and P ≤ .05 was considered statistically significant. There were significant decreases in FPG (5.7 ± 0.4 vs. 5.5 ± 0.4 mmol/L, P = .002), insulinogenic index (0.71 ± 0.25 vs. 0.63 ± 0.25, P = .028), body weight, body mass index, waist circumference, triglycerides, total cholesterol, low-density lipoprotein cholesterol, and very low-density lipoprotein levels in the chlorogenic acid group, with an increment in the Matsuda index (1.98 ± 0.88 vs. 2.30 ± 1.23, P = .002). There were no significant differences in the placebo group. In conclusion, chlorogenic acid administration in patients with IGT decreased FPG and insulin secretion, while increasing insulin sensitivity and improving both anthropometric evaluations and the lipid profile.


Subject(s)
Chlorogenic Acid/administration & dosage , Glucose Intolerance/drug therapy , Insulin Resistance , Insulin/metabolism , Adult , Blood Glucose/metabolism , Body Mass Index , Cholesterol/blood , Dose-Response Relationship, Drug , Double-Blind Method , Exercise , Female , Humans , Insulin/blood , Insulin Secretion , Male , Middle Aged , Triglycerides/blood
13.
J Med Food ; 20(8): 750-754, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28459647

ABSTRACT

Gymnema sylvestre is a medicinal plant whose consumption has demonstrated benefits on lipid and glucose levels, blood pressure, and body weight (BWt). The aim of this study was to evaluate the effect of G. sylvestre administration on metabolic syndrome (MetS), insulin secretion, and insulin sensitivity. A randomized, double-blind, placebo-controlled clinical trial was carried out in 24 patients (without pharmacological treatment), 30-60 years old, with diagnosis of MetS in accordance with the modified International Diabetes Federation criteria. Patients were randomly assigned to receive G. sylvestre or placebo twice daily before breakfast and dinner in 300 mg capsules for a total of 600 mg per day for 12 weeks. Before and after the intervention, the components of MetS were evaluated as well as BWt, body mass index (BMI), total cholesterol, low-density lipoprotein cholesterol, and very low-density lipoprotein (VLDL). Area under the curve of glucose and insulin, phases of insulin secretion, and insulin sensitivity were calculated. Statistical analysis was performed using Wilcoxon signed-rank, Mann-Whitney U, and chi-square tests; P ≤ .05 was considered statistically significant. After G. sylvestre administration, significant decreases in BWt (81.3 ± 10.6 kg vs. 77.9 ± 8.4 kg, P = .02), BMI (31.2 ± 2.5 kg/m2 vs. 30.4 ± 2.2 kg/m2, P = .02), and VLDL levels (0.45 ± 0.15 mmol/dL vs. 0.35 ± 0.15 mmol/dL, P = .05) were observed, without modifying the components of MetS, insulin secretion, and insulin sensitivity. In conclusion, G. sylvestre administration decreased BWt, BMI, and VLDL levels in subjects with MetS, without changes in insulin secretion and insulin sensitivity.


Subject(s)
Gymnema sylvestre/chemistry , Insulin/metabolism , Metabolic Syndrome/drug therapy , Plant Extracts/administration & dosage , Adult , Blood Glucose/metabolism , Cholesterol/blood , Cholesterol, VLDL/blood , Double-Blind Method , Female , Humans , Male , Metabolic Syndrome/metabolism , Middle Aged , Triglycerides/blood
14.
World J Diabetes ; 7(7): 142-52, 2016 Apr 10.
Article in English | MEDLINE | ID: mdl-27076875

ABSTRACT

Nutraceutic therapies such as berberine, bitter melon, Gymnema sylvestre, Irvingia gabonensis, resveratrol and ursolic acid have been shown to help control metabolic syndrome (MetS). The effect of berberine on glucose and lipid metabolism, hypertension, obesity and MetS has been evaluated in animal models and humans. Most clinical trials involving bitter melon have been conducted to evaluate its effect on glucose metabolism; nevertheless, some studies have reported favorable effects on lipids and blood pressure although there is little information about its effect on body weight. Gymnema sylvestre helps to decrease body weight and blood sugar levels; however, there is limited information on dyslipidemia and hypertension. Clinical trials of Irvingia gabonensis have shown important effects decreasing glucose and cholesterol concentrations as well decreasing body weight. Resveratrol acts through different mechanisms to decrease blood pressure, lipids, glucose and weight, showing its effects on the population with MetS. Finally, there is evidence of positive effects with ursolic acid in in vitro and in vivo studies on glucose and lipid metabolism and on body weight and visceral fat. Therefore, a review of the beneficial effects and limitations of the above-mentioned nutraceutic therapies is presented.

15.
Interciencia ; 33(11): 829-834, nov. 2008. ilus, tab
Article in Spanish | LILACS | ID: lil-630700

ABSTRACT

La presencia de grietas internas dentro de los anillos de crecimiento fue relacionada con la densidad y las características anatómicas de un árbol de Eucalyptus nitens. El diseño experimental incluyó como variables la posición radial y apical. Las grietas internas fueron evaluadas después del secado al aire y a 60ºC. Las características anatómicas y la densidad fueron determinadas mediante métodos normalizados y apoyo de rayos X. La intensidad de las grietas internas fue condicionada por la posición radial y apical en el árbol. Las grietas internas fueron más intensas entre los anillos 4 a 9, y se relacionaron inversamente con la densidad de la madera y directamente con la proporción y diámetro de vasos.


Internal checks within growth rings were correlated with density and anatomical characteristics of Eucalyptus nitens. The radial and longitudinal positions in the tree were the experimental variables. Internal checks were characterized after air drying and after conventional drying at 60°C. The anatomical characteristics and density were determined using standardized methods and the X-ray technique. The size of internal checks was influenced by their radial and longitudinal positions in the tree. Internal checks were larger in growth rings 4 to 9, and were inversely related to wood density and directly related to the proportion and diameter of the vessels.


A presença de fissuras internas dentro dos anéis de crescimento foi relacionada com a densidade e as características anatômicas de uma árvore de Eucaliptus nitens. O desenho experimental incluiu como variáveis a posição radial e apical. As fissuras internas foram avaliadas depois da secagem ao ar e a 60ºC. As características anatômicas e a densidade foram determinadas mediante métodos normalizados e apoio de raios X. A intensidade das fissuras internas foi condicionada pela posição radial e apical na árvore. As fissuras internas foram mais intensas entre os anéis 4 a 9, e se relacionaram inversamente com a densidade da madeira e diretamente com a proporção e diâmetro de vasos.

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