[Hyperinsulinemia and insulin resistance in children]

BACKGROUND

Obesity during childhood is a risk factor for developing cardiovascular diseases during adulthood.

AIM

To measure insulin and glucose levels and parameters of insulin resistance in obese, overweight and normal weight Mexican children.

MATERIAL AND METHODS

Comparative study of 21 obese children with a body mass index (BMI) over percentile 95, aged 10 ± 1 years (10 males), 14 children aged 10 ± 2 (7 males) with a BMI between percentiles 85 and 94 and 16 children aged 9 ± 2 years (3 males) with a body mass index between percentiles 10 and 84. Body weight, blood pressure and waist circumference were measured and a blood sample was obtained to measure fasting glucose and insulin levels. Homeostasis model of insulin resistance (HOMA) and quantitative insulin sensitivity check index (QUICKI) were calculated.

RESULTS

Among obese, overweight and normal weight children, insulin levels were 14.9 (95% CI 10.90-18.99), 7.20 (CI 5.12-9.28) and 4.73 (CI 95% 1.92-7.53) uU/ml, respectively. The figures for HOMA were 3.16 (95% CI 2.20-4.12), 1.49 (95% CI 1.03-1.94) and 0.97 (95% CI 0.35-1.60), respectively. The figures for QUICKI were 0.331 (95% CI 0.319-0.343), 0.371 (95% CI 0.349-0.393) and 0.419 (95% CI 0.391-0.446), respectively. Compared to their normal weight counterparts, the risk of obese children and those with a waist circumference over percentile 90 of having a HOMA over 3.16 was 17 and 10 times higher, respectively. BMI correlated better than waist circumference with insulin levels.

CONCLUSIONS

Obese children have higher levels of insulin resistance than their normal weight counterparts.

[A GENETIC VIEW OF FAMILIAL HYPERCHOLESTEROLEMIA]

OBJECTIVE

to show reviewed information of published studies relating to Familial Hypercholesterolemia (FH), nutrition, and genes involved in the development of this pathology.

RESULTS

an analysis showing familial hypercholesterolemia as a disorder occuring due to mutations in gene encoding of the LDL receptor, which can be transmitted as an autosomal dominant or autosomal recessive. It's diagnosis is important for those with a greater likelihood of premature coronary disease, and can significantly reduce life expectancy.

CONCLUSIONS

there are no specific clinical criteria with absolute predictive value for the diagnosis of HF, Genetic diagnosis can prove functional defects in the LDL receptor gene, constituting definitive confirmation of the diagnosis, thus the importance of presenting a genetic vision of development of this disease, which can be treated adequately through diet therapy affecting future generations in the family concerned.

Purification and Partial Characterization of β-Glucosidase in Chayote (Sechium edule)

β-Glucosidase (EC 3.2.1.21) is a prominent member of the GH1 family of glycoside hydrolases. The properties of this β-glucosidase appear to include resistance to temperature, urea, and iodoacetamide, and it is activated by 2-ME, similar to other members. β-Glucosidase from chayote (Sechium edule) was purified by ionic-interchange chromatography and molecular exclusion chromatography. Peptides detected by LC-ESI-MS/MS were compared with other β-glucosidases using the BLAST program. This enzyme is a 116 kDa protein composed of two sub-units of 58 kDa and shows homology with Cucumis sativus β-glucosidase (NCBI reference sequence XP_004154617.1), in which seven peptides were found with relative masses ranging from 874.3643 to 1587.8297. The stability of β-glucosidase depends on an initial concentration of 0.2 mg/mL of protein at pH 5.0 which decreases by 33% in a period of 30 h, and then stabilizes and is active for the next 5 days (pH 4.0 gives similar results). One hundred μg/mL β-D-glucose inhibited β-glucosidase activity by more than 50%. The enzyme had a Km of 4.88 mM with p-NPG and a Kcat of 10,000 min(-1). The optimal conditions for the enzyme require a pH of 4.0 and a temperature of 50 °C.

Edentulism and other variables associated with self-reported health status in Mexican adults

BACKGROUND

To determine if edentulism, controlling for other known factors, is associated with subjective self-report health status (SRH) in Mexican adults.

MATERIAL AND METHODS

We examined the SRH of 13 966 individuals 35 years and older, using data from the National Survey of Performance Assessment, a cross-sectional study that is part of the technical collaboration between the Ministry of Health of Mexico and the World Health Organization, which used the survey instrument and sampling strategies developed by WHO for the World Health Survey. Sociodemographic, socioeconomic, medical, and behavioral variables were collected using questionnaires. Self-reported health was our dependent variable. Data on edentulism were available from 20 of the 32 Mexican states. A polynomial logistic regression model adjusted for complex sampling was generated.

RESULTS

In the SRH, 58.2% reported their health status as very good/good, 33.8% said they had a moderate health status, and 8.0% reported that their health was bad/very bad. The association between edentulism and SRH was modified by age and was significant only for bad/very bad SRH. Higher odds of reporting moderate health or poor/very poor health were found in women, people with lower socio-economic status and with physical disabilities, those who were not physically active, or those who were underweight or obese, those who had any chronic disease, and those who used alcohol.

CONCLUSIONS

The association of edentulism with a self-report of a poor health status (poor/very poor) was higher in young people than in adults. The results suggest socioeconomic inequalities in SRH. Inequality was further confirmed among people who had a general health condition or a disability. Dentists and health care professionals need to recognize the effect of edentulism on quality of life among elders people.

National survey of oral/dental conditions related to tobacco and alcohol use in Mexican adults

Oral diseases are a major burden on individuals and health systems. The aim of this study was to determine whether consumption of tobacco and alcohol were associated with the prevalence of oral/dental problems in Mexican adults. Using data from the National Performance Evaluation Survey 2003, a cross-sectional study part of the World Health Survey, dental information from a representative sample of Mexico (n = 22,229, N = 51,155,740) was used to document self-reported oral/dental problems in the 12 months prior to the survey. Questionnaires were used to collect information related to sociodemographic, socioeconomic, and other risk factors. Three models were generated for each age group (18–30, 31–45 and 46–98 years). The prevalence of oral/dental conditions was 25.7%. Adjusting for sex, schooling, socioeconomic position, diabetes, and self-reported health, those who used tobacco (sometimes or daily) (OR = 1.15, p = 0.070; OR = 1.24, p < 0.01; and OR = 1.16, p < 0.05, for each age group respectively) or alcohol (moderate or high) (OR = 1.26, p < 0.001; OR = 1.18, p < 0.01 and OR = 1.30, p < 0.001, for each age group respectively) had a higher risk of reporting oral/dental problems. Because tobacco and alcohol use were associated with self-reported oral/dental problems in one out of four adults, it appears advisable to ascertain how direct is such link; more direct effects would lend greater weight to adopting measures to reduce consumption of tobacco and alcohol for the specific purpose of improving oral health.

[Asymptomatic human infection from contact with dogs: a case of human ehrlichiosis]

INTRODUCTION

Living with dogs leads one to consider the necessity of identifying canine infections found in the people with whom the dogs live.

OBJECTIVE

Dogs which were clinically and serologically positive with the infections Ehirlichia canis, Anaplasma phagocytophilum, Borrelia burgdorferi, and Dirofilaria Immitis were sought. People with the same infections were also identified.

MATERIAL AND METHODS

From a population of 80 dogs identified in the villages of San Bartolo Coyotepec and San Agustín Etla (suburbs peripheral to the city of Oaxaca, Mexico), 27 dogs were selected for study, all of which had adenomegaly, hepatomegaly, splenomegaly, and fevers of at least 43° C. Using enzyme immunoassay in this population of dogs and their closest human contacts, antibodies for Ehirlichia canis, Anaplasma phagocytophilum, Borrelia burgdorferi, and the antigen for Dirofilaria immitis were sought. Positive results in humans were confirmed by polymerase chain reaction (PCR).

RESULTS

Ten dogs with the clinical signs mentioned above tested positive for antibodies to Ehrlichia canis; two cases tested positive for Anaplasma phagocytophilum; one case tested positive for Dirofilaria Immitis. From human contact, one person tested positive for Ehirlichia canis; this case was confirmed by DNA amplification by means of PCR.

CONCLUSION

It is necessary to identify the population of sick dogs in order to reduce related infections in people.

Better detection of platelet aggregation in patients with metabolic syndrome using epinephrine and ADP

BACKGROUND

Patients with metabolic syndrome (MS) often have increased platelet aggregation. In order to determine which concentration detects a higher level of platelet aggregation in patients with MS, the agonists ADP and epinephrine were compared.

METHODS

The study included 56 subjects with MS and 53 healthy subjects. Blood pressure, weight, body-mass index, and hip-to-waist ratio were collected from all subjects. Insulin, glucose, total serum cholesterol, HDL-C, LDL-C, total triglycerides, markers of plasma atherogenicity, and indices of insulin resistance were measured in all participants. For aggregometry assays, the Born method was used. Platelets were treated with ADP and epinephrine in decreasing concentrations of 2.34, 1.17, and 0.58 μM, as well as, 11.0, 1.1, and 0.55 μM, respectively. ROC curves were plotted to define the diagnostic efficiency of epinephrine levels for MS.

RESULTS

Among healthy individuals and MS patients significant differences were observed in body weight, body-mass index, waist-circumference, levels of insulin, indices of insulin resistance, and levels of HDL-cholesterol, LDL-cholesterol and total triglycerides. There was a significant difference in the detection of increased platelet aggregation using 11.0 μM and 0.55 μM epinephrine and 0.58 μM ADP. With both agonists, ROC analysis showed an area under the curve of >0.8 for 11.0 μM epinephrine and 2.34 μM ADP. However, for MS patients, 11.0 μM epinephrine had a slightly better diagnostic efficiency than 2.34 μM ADP.

CONCLUSIONS

It was found that 11.0 μM epinephrine and 2.34 μM ADP detected better platelet aggregation in patients with MS than in healthy subject. Both concentrations detected increased platelet aggregation in patients with MS.

Association between edentulism and angina pectoris in Mexican adults aged 35 years and older: a multivariate analysis of a population-based survey

BACKGROUND

The possible association between oral infection and chronic inflammation and cardiovascular disease risk has been studied intensively. The present study is designed to determine the strength of association between edentulism and angina pectoris in Mexican adults aged 35 years and older.

METHODS

Using the tools and sampling strategies of the World Health Survey of the World Health Organization, cross-sectional data were collected in Mexico in the National Performance Assessment Survey (probabilistic, multistage, and cluster sampling). Dental information was available for 20 of the 32 states of Mexico. Angina and edentulism are self-reported in this study. Statistical analysis was performed using binary logistic regression adjusting for complex samples.

RESULTS

A total of 13,966 participants, representing a population of 29,853,607 individuals, were included. Of the complete study population, 3,052,263 (10.2%) were completely toothless, and 673,810 (2.3%) were diagnosed with angina pectoris. After adjusting for smoking, alcohol consumption, diabetes, body mass index, and sex, the effect of edentulism on angina was modified by age (interaction), being more marked in the younger age group (odds ratio [OR] = exp(2.5597) =12.93) than in the older individuals surveyed (OR = exp(2.5597 + (-0.0334)) =12.51). Additionally, low physical activity (OR = 1.51; 95% confidence interval [CI] = 1.03 to 2.22) and higher socioeconomic status (OR = 1.37; 95% CI = 1.00 to 1.90) were more likely to be associated with angina pectoris.

CONCLUSIONS

Overall, the results of this study, conducted in a representative sample of Mexican adults, suggest that an association exists between edentulism and angina pectoris. Additional studies are necessary to elucidate the underlying mechanism for this association.

[Principal reasons for extraction of permanent tooth in a sample of Mexicans adults]

BACKGROUND

Tooth extractions are one of the most common procedures in oral surgery. The objective of this study was to identify the reasons for tooth extraction in adult patients seeking care at teaching dental clinics.

MATERIAL AND METHODS

A cross-sectional study was carried out in 331 subjects between 18 and 85 (45.37 +/- 13.85) years of age seeking dental care in dental clinics of the Universidad Autónoma del Estado de Hidalgo, from January 2009 to December, 2009. Data pertaining to age, sex, tooth number and the reason for extraction according to Kay & Blinkhorn were analyzed with non-parametric tests.

RESULTS

779 extractions were undertaken. The main reason for extraction was dental caries (43.1%), periodontal disease (PD) (27.9%), and prosthetic reasons (21.5%). There was no significant difference across sex for reasons of extraction (p > 0.05). Significant differences (p < 0.001) were found for age (extraction due to periodontal disease increased with age); in patients attending in a single visit vs. patients attending a series of dental appointments (caries reasons were more common in patients having a single appointment vs. PD in those attending a series of appointments); for type of teeth (upper, posterior, and molars were extracted primarily because of caries, while lower, anterior and incisors were more often extracted because of PD).

CONCLUSIONS

Dental caries was the most common reason for tooth extraction, followed by periodontal disease. Differences in the reasons for extraction were observed across patient characteristics and type of tooth.

Expression of antigen tf and galectin-3 in fibroadenoma

Background

Fibroadenomas are benign human breast tumors, characterized by proliferation of epithelial and stromal components of the terminal ductal unit. They may grow, regress or remain unchanged, as the hormonal environment of the patient changes. Expression of antigen TF in mucin or mucin-type glycoproteins and of galectin-3 seems to contribute to proliferation and transformations events; their expression has been reported in ductal breast cancer and in aggressive tumors.

Findings

Lectin histochemistry, immunohistochemistry, and immunofluorescence were used to examine the expression and distribution of antigen TF and galectin-3. We used lectins from Arachis hypogaea, Artocarpus integrifolia, and Amaranthus lecuocarpus to evaluate TF expression and a monoclonal antibody to evaluate galectin-3 expression. We used paraffin-embedded blocks from 10 breast tissues diagnosed with fibroadenoma and as control 10 healthy tissue samples. Histochemical and immunofluorescence analysis showed positive expression of galectin-3 in fibroadenoma tissue, mainly in stroma, weak interaction in ducts was observed; whereas, in healthy tissue samples the staining was also weak in ducts. Lectins from A. leucocarpus and A. integrifolia specificaly recognized ducts in healthy breast samples, whereas the lectin from A. hypogaea recognized ducts and stroma. In fibroadenoma tissue, the lectins from A. integrifolia, A. Hypogaea, and A. leucocarpus recognized mainly ducts.

Conclusions

Our results suggest that expression of antigen TF and galectin-3 seems to participate in fibroadenoma development.

Protein C activation peptide inhibits the expression of ICAM-1, VCAM-1, and interleukin-8 induced by TNF-α in human dermal microvascular endothelial cells

Activated protein C (APC) is generated from the cleavage of protein C by thrombin coupled to thrombomodulin and, subsequently, is released as protein C activation peptide (papC). The aim of this study was to evaluate the effect of papC on human dermal microvascular endothelial cells (HMEC-1), activated with 5 ng//mL TNF-α. Flow cytometry showed that papC inhibited the expression of VCAM-1 and ICAM-1, after activation with TNF-a. Similarly, RT-PCR analysis revealed that 2 and 4 pM papC inhibited the expression of VCAM-1 and IL-8 mRNA in TNF-α-treated HMEC-1. In addition, the expression of endothelial nitric oxide synthase(eNOS) increased in HMEC-1 treated with papC, compared to those without treatment. Furthermore, Jurkat cell adhesion to HMEC-1 induced by TNF-a was significantly inhibited after the addition of papC, compared to HMEC-1 without papC (p = 0.03). Finally, a control peptide analog to papC showed no effect on the expression of ICAM and VCAM on the surface of HMEC-1. In conclusion, our results suggest that papC exerts anti-inflammatory effects on endothelial cells.

The relationship of aluminium and silver to neural tube defects; a case control

OBJECTIVE

The purpose of this study was to identify the relationship of neurotoxic inorganic elements in the hair of patients with the diagnosis of Neural Tube Defects. Our initial hypothesis was that neurotoxic inorganic elements were associated with Neural Tube Defects.

METHODS

Twenty-three samples of hair from newborns were obtained from the General Hospital, "Aurelio Valdivieso" in the city of Oaxaca, Mexico. The study group included 8 newborn infants with neural tube pathology. The control group was composed of 15 newborns without this pathology. The presence of inorganic elements in the hair samples was determined by inductively-coupled plasma spectroscopy (spectroscopic emission of the plasma).

FINDINGS

THE POPULATION OF NEWBORNS WITH NEURAL TUBE DEFECTS SHOWED SIGNIFICANTLY HIGHER VALUES OF THE FOLLOWING ELEMENTS THAN THE CONTROL GROUP: Aluminium, Neural Tube Defects 152.77±51.06 µg/g, control group 76.24±27.89 µg/g; Silver, Neural Tube Defects 1.45±0.76, control group 0.25±0.53 µg/g; Potassium, Neural Tube Defects 553.87±77.91 µg/g, control group 341.13±205.90 µg/g. Association was found at 75 percentile between aluminium plus silver, aluminium plus potassium, silver plus potassium, and potassium plus sodium.

CONCLUSION

IN THE HAIR OF NEWBORNS WITH NEURAL TUBE DEFECTS, THE FOLLOWING METALS WERE INCREASED: aluminium, silver. Given the neurotoxicity of the same, and association of Neural Tube Defects with aluminum and silver, one may infer that they may be participating as factors in the development of Neural Tube Defects.

A study on inorganic elements in psammomas from ovarian & thyroid cancer

BACKGROUND & OBJECTIVES

Concentric lamellar calcifications known as psammoma bodies (PB) are found in benign and malignant tumours. Whether or not the inorganic element concentrations in psammomas are similar to serous adenocarcinoma of the ovary and thyroid papillary cancer tissues has not yet been ascertained. We undertook this retrospective study to establish if there is any difference in the concentrations of inorganic ions found in psammomas in serous adenocarcinoma of the ovary, and those found in thyroid papillary cancer tissue.

METHODS

PB samples from patients with adenocarcinoma of the ovary (n = 10) and with thyroid papillary cancer (n = 10) were analyzed through inductively-coupled plasma spectroscopy (ICP).

RESULTS

There were no significant differences in the concentrations of inorganic elements in PB from thyroid papillary cancer than in those PB from ovarian cancer.

INTERPRETATION & CONCLUSIONS

Differences in the concentrations of inorganic elements may be due to the variation in environmental pollution. Our study had limitation of small sample size. Our results suggest that some inorganic elements can participate in the origin of psammoma bodies.

Color of meconium and interleukin-6

OBJECTIVE

To test the hypothesis that the color of meconial fluid is associated with inflammatory biomarkers, by determining C-reactive protein (CRP) and Interleukin-6 (IL-6) in serum from the umbilical cord.

METHODS

In this prospective study, the authors selected 30 newborns with meconium-stained amniotic fluid (MSAF): 14 with green/brown 656 R color and 16 with brown/cinnamon 654 R color, and 20 newborns which showed clear amniotic fluid without MSAF (non-MSAF); all newborns were from mothers without risk factors for neonatal sepsis.

RESULTS

IL-6 concentration from umbilical cord blood, [median of 12.9 pg/mL (interquartile range {IQR} 8.7-31.0)] of MSAF-green/brown 656 R increased significantly (p < 0.05) when compared with IL-6 concentration, [median of 9.2 pg/mL (IQR 7.2-12.2)] of newborns with clear amniotic fluid and without meconium. CRP from MSAF-green/brown 656 R was median of 0.5 mg/mL (IQR 0.0-2.7), and median of 1.0 mg/mL (IQR 0.0-5.5) from clear amniotic fluid, without meconium.

CONCLUSIONS

Significant association was found between MSAF-green/brown 656 R and increase in IL-6, with normal CRP values.

Glycosylation pattern in the appendix testis in children with cryptorchidism

In humans, at about week 6, sex cords develop within the forming testes. Testes normally descend to the scrotum; cryptorchidism occurs when one or two testes do not descend to scrotum and in some case are accompanied by the appendix testis. The appendix testis is a small sessile or polypoid structure located at the antero superior pole of the testis, adjacent to the head of the epididymis. Glycans can be involved in development of the appendix testis and cryptorchidism. In this work, lectin histochemistry was used to evaluate glycans expression in appendix testis in children with cryptorchidism. Our results showed that lectin from Lens culinaris, Ulex europaeus I., Canavalia ensiformis, Artocarpus integrifolia, Glycine max, and Griffonia simplicifolia recognizes epithelial and estromal cells. Not interaction was observed with lectin from Amaranthus leucocarpus, while lectin from Dolichus biflorus lectin only recognizes epithelial cells. Our results suggest that O-glycans linked in some glycoproteins represent important elements in appendix testis development.

O-glycosylation expression in fibroadenoma

Fibroadenomas are human benign breast tumors characterized by proliferation of epithelial and stroma cells of the terminal ductal unit. Expression of O-glycans seems to contribute to the proliferation and transformation events. With this in mind, we evaluated the expression of glycans in fibroadenoma tissue through immunohistochemistry with antibodies against mucin epitopes (Anti CA15-3 and MUC1), as well as with lectins specific for glycans linked to proteins or lipids, and we compared findings with healthy breast specimens. Our results show positive expression of CA15-3 and MUC1 in fibroadenoma tissue, mainly in duct and stroma cells, whereas, in normal samples, staining was observed in duct cells. The lectin from Glycine max recognized equally well duct and stroma cells; this was the only lectin showing co-localization with anti-CA15-3 in healthy and tumor tissues. Dolichos biflorus, Artocarpus integrifolia, and Griffonia simplicifolia lectins recognized duct cells in control healthy tissues as well as in fibroadenoma tissue. The lectin from Amaranthus leucocarpus recognized only duct cells in control samples, whereas, in fibroadenoma tissue, it recognized duct and some stromal cells, suggesting that O-glycans-type mucin linked to proteins and mucin participate in the development of fibroadenomas.

[Platelet abnormalities in type 2 diabetes mellitus]

Diabetes mellitus is a problem of health worldwide being vascular complications the main causes of morbidity and mortality in this population. Diabetics have a fast atherothrombotic evolution which is worse than that observed for other clinical entities; however, hyperglycemia itself may not totally explain the ischemic complications observed in these patients. Most ischemic arterial events are precipitated by plaque rupture, platelet activation, and thrombosis. Several abnormalities in the blood coagulation system have been described associated to diabetes mellitus, all of them predisposing to thrombosis: endothelial cell dysfunction, platelet hyperreactivity, thrombin generation and hypofibrinolysis. Platelets play a key role in diabetic atherothrombosis due to platelet hypersensitivity to physiological agonists, low response to therapeutical antiplatelet agents, platelet hyperreactivity in sites of endothelial cell damage, hyperaggregability, resistance to the inhibitory effects of the insulin, and low endothelial production of prostacyclin and nitric oxide. All these phenomena have been associated to either a toxic microenvironment due to hyperglycemia or to intrinsic platelet abnormalities. Based on all these facts, it is proposed that platelets may be another target for the negative effects of insulin-resistance state. Because platelets are crucial in the atherosclerotic process and in the genesis of the vascular complications of diabetes mellitus, this review analyses the platelet abnormalities observed in this metabolic disease.

Lectin activity of the coagulation factor VIII/von Willebrand complex

The human coagulation factor VIII (FVIII) is essential in the intrinsic pathway of blood coagulation and circulates mainly as a non-covalently bound complex with the von Willebrand factor (VWF). This complex (FVIII/VWF) protects FVIII from degradation and cellular uptake, although no biological role has been identified yet for this complex. The FVIII/VWF complex was purified from a healthy donor's plasma by affinity chromatography on a Sepharose 4B-Concanavalin A column and was used to determine its capability to interact with erythrocytes and platelets. The purified FVIII/VWF complex at 6.0 and 12 microg/ml agglutinates rabbit and bovine erythrocytes, and showed negative agglutination with erythrocytes from other species including human ABO. Treatment of erythrocytes with Clostridium perfringens sialidase or trypsin increased four-fold the activity toward rabbit erythrocytes and positive agglutination for human A and B erythrocytes, suggesting the presence of FVIII/VWF-cryptic receptors in these erythrocytes. Goat, pig, or human O erythrocytes were not agglutinated even after enzymatic treatment. Fucose or N-acetyl-glucosamine (GlcNAc), at 10 mM, inhibited agglutinating activity of the complex with rabbit, human A and B erythrocytes, whereas galactose and N-acetyl-galactosamine, even at 200 mM, showed no effect on the complex activity. The FVIII/VWF complex, at 1.5 microg/200,000 platelets, significantly decreased platelet aggregation (p < 0.001) when compared with the effect of platelet-rich plasma; this effect was inhibited with 15 mM GlcNAc or fucose. ELISA assays on FVIII/VWF coated polystyrene plates confirmed specific binding to fucose- or biotinylated GlcNAc-dextran derivatives. We therefore propose that the FVIII/VWF complex possesses lectin activity.

Potential use of the Macrobrachium rosenbergii lectin for diagnosis of T-cell acute lymphoblastic leukemia

T-cell acute lymphoblastic leukemia is the most common form of cancer in children. Lectins are proteins or glycoproteins from plants or animals that recognize oligossacharides on the cell surface and have been used to characterize the structural changes of oligosaccharides in leukemias. In this study, we used the lectin from the freshwater prawn Macrobrachium (M. rosenbergii), specific for acetyl groups in sialylated glycans, because increased sialylation of glycoproteins and glycolipids has been identified in lymphoblastic leukemias. We compared the specificity of the M. rosenbergii lectin for lymphoblastic leukemias with the specificities of the lectins from Triticum vulgaris, Solanum tuberosum, Arachis hipogaea, and Phytolacca americana. By morphologic and phenotype characterization with a panel of monoclonal antibodies, we identified four types of leukemias from 106 leukemia patients: 11 cases of T-cell acute lymphoblastic leukemia, 61 cases of B-cell acute lymphoblastic leukemia, 24 cases of acute myeloblastic leukemia, and 10 cases of acute biphenotypic leukemia. As determined by cytofluorometric assays, nine of the eleven cases with T-cell acute lymphoblastic leukemia (8 +/- 3 years old) were specifically identified with the lectin from M. rosenbergii. In contrast, only six cases of B-cell leukemia, one case of myeloblastic leukemia, and 2 cases of biphenotypic leukemia were identified with this M. rosenbergii lectin. The other lectins tested showed no capacity to differentiate, in a significant manner, any of the four types of leukemias tested. Thus, the lectin from M. rosenbergii could be considered a useful tool for the diagnosis and study of T-cell acute lymphoblastic leukemia.

Role of concanavalin A lectin in recognition of pterygium remnant after surgical excision: preliminary results of a prospective study

Background:

Pterygium is one of the most common conjunctival diseases among ophthalmic pathologies. The frequency of recurrences is high, either after surgical treatment or after treatment combined with mitomycin C or beta-radiation therapy.

Aims:

The purpose of this study was to determine whether concanavalin A (ConA) lectin bound to the pterygial surface can be used to detect recurrence or remnants of pterygium after surgical excision.

Materials and Methods:

This was a prospective study on 20 patients with pterygium, divided in five stages, pre-surgery, early post-surgery (24h), late post-surgery (seven days), very late post-surgery (four weeks) and two months after the procedure.

A drop of fluorescein-marked Con A (35 µg/mL) was instilled in the lower conjunctival eyelid sac and the eye was exposed to the light of a Wood′s lamp for an average of five seconds.

Results:

Out of the 20 patients, eight patients were found to have fluorescent stretch marks over the scar corresponding to residual pterygial tissue at four weeks; two months after the procedure of re-surgery we observed no fluorescent remnants. All residual pterygia were confirmed through histochemistry studies.

Conclusion:

It was possible to detect remnants of pterygium in postoperative patients and recurrences in early pre-clinical stages through the visualization of fluorescent ConA bound to the pterygial surface.

Use ofAmaranthus leucocarpusLectin to Differentiate Cervical Dysplasia (CIN)

Alterations in O-glycosylation of proteins in cell surfaces can originate disorder in cellular function, as well as in cell transformation and tumoral differentiation. In this work, we investigate changes in O-glycosylation in cervical intraepithelial dysplasia (CIN) at different stages of differentiation (CIN I, CIN II, and CIN III) using lectins specific for O-glycosidically linked glycans. Twenty cases with CIN I, CIN II, and CIN III dysplasias each, and 20 normal cases were studied by lectin histochemistry and evaluated under optical microscopy. The lectins from Glycine max and Griffonia simplicifolia showed no differences in their recognition pattern among the different CIN stages and normal tissue. Dolichos Biflorus lectin recognized CIN I dysplasia. Lectin from Amaranthus leucocarpus showed increased reactivity in the presence of CIN II dysplasia, compared with CIN I and CIN III. These results suggest that subtle modifications in the O-glycosylation pattern could be considered in diagnosis or prognosis of cervical precancerous stages.