Contribution Of Different Factors Research Articles

Munc13-1 is required for the sustained release of insulin from pancreatic β cells

Munc13-1 is a presynaptic protein that is essential for synaptic vesicle priming. Deletion of Munc13-1/unc13 causes total arrest of synaptic transmission due to a complete loss of fusion-competent synaptic vesicles. The requirement of Munc13-1 for large dense-core vesicles (LDCVs), however, has not been established. In the present study, we use Munc13-1 knockout (KO) and diacylglycerol (DAG) binding-deficient Munc13-1(H567K) mutant knockin (KI) mice to determine the role of Munc13-1 in the secretion of insulin-containing LDCVs from primary cultured pancreatic beta cells. We show that Munc13-1 is required for the sustained insulin release upon prolonged stimulation. The sustained release involves signaling of DAG second messenger, since it is also reduced in KI mice. Insulin secretion in response to glucose stimulation is characterized by a biphasic time course. Our data show that Munc13-1 plays an essential role in the development of the second phase of insulin secretion by priming insulin-containing LDCVs.

Quorum sensing and motility mediate interactions between Pseudomonas aeruginosa and Agrobacterium tumefaciens in biofilm cocultures

In the environment, multiple microbial taxa typically coexist as communities, competing for resources and, often, physically associated within biofilms. A dual-species cocultivation model has been developed by using two ubiquitous and well studied microbes Pseudomonas aeruginosa (P.a.) and Agrobacterium tumefaciens (A.t.) as a tractable system to identify molecular mechanisms that underlie multispecies microbial associations. Several factors were found to influence coculture interactions. P.a. had a distinct growth-rate advantage in cocultures, increasing its relative abundance during planktonic and biofilm growth. P.a. also demonstrated a slight quorum-sensing-dependent increase in growth yield in liquid cocultures. P.a. dominated coculture biofilms, "blanketing" or burying immature A.t. microcolonies. P.a. flagellar and type IV pili mutant strains exhibited deficient blanketing and impaired competition in coculture biofilms, whereas, in planktonic coculture, these mutations had no effect on competition. In contrast, A.t. used motility to emigrate from coculture biofilms. In both planktonic and biofilm cocultures, A.t. remained viable for extended periods of time, coexisting with its more numerous competitor. These findings reveal that quorum-sensing-regulated functions and surface motility are important microbial competition factors for P.a. and that the outcome of competition and the relative contribution of different factors to competition are strongly influenced by the environment in which they occur.

UniFrac: a New Phylogenetic Method for Comparing Microbial Communities

We introduce here a new method for computing differences between microbial communities based on phylogenetic information. This method, UniFrac, measures the phylogenetic distance between sets of taxa in a phylogenetic tree as the fraction of the branch length of the tree that leads to descendants from either one environment or the other, but not both. UniFrac can be used to determine whether communities are significantly different, to compare many communities simultaneously using clustering and ordination techniques, and to measure the relative contributions of different factors, such as chemistry and geography, to similarities between samples. We demonstrate the utility of UniFrac by applying it to published 16S rRNA gene libraries from cultured isolates and environmental clones of bacteria in marine sediment, water, and ice. Our results reveal that (i) cultured isolates from ice, water, and sediment resemble each other and environmental clone sequences from sea ice, but not environmental clone sequences from sediment and water; (ii) the geographical location does not correlate strongly with bacterial community differences in ice and sediment from the Arctic and Antarctic; and (iii) bacterial communities differ between terrestrially impacted seawater (whether polar or temperate) and warm oligotrophic seawater, whereas those in individual seawater samples are not more similar to each other than to those in sediment or ice samples. These results illustrate that UniFrac provides a new way of characterizing microbial communities, using the wealth of environmental rRNA sequences, and allows quantitative insight into the factors that underlie the distribution of lineages among environments.

Comportamiento de las muertes violentas en Bogotá, 1997-2003

To describe patterns of violent deaths in Bogotá between 1997 and 2003. Descriptive methods for analyzing time series were applied to a group of 84 observations corresponding to mortality due to violent causes during seven years in Bogotá. Box-Jenkins methodology was used to generate forecasts for 12 months. Primary and secondary sources of information: Instituto de Medicina Legal Bogotá, Departamento Administrativo Nacional de Estadística, Colombia. For the 4 types of violent deaths analyzed (homicide, transit accident, suicide and others accidents), a decreasing tendency in the number of deaths during the analyzed period was observed, more evident in homicide and transit accidents. In all cases, except in the group of suicides, evidence of seasonality, with an increase in frequency of deaths in December, has been observed. The forecasting suggests persistence of decreasing trends, more apparent in the series of homicide and transit accidents. In Bogotá, the mortality caused by violence has presented a decreasing trend. Stabilization of trend is observed in cases of suicides and accidental deaths. Further study is required to characterize and evaluate the contribution of different factors in this dynamic of violent death.

Landslides in Sado Island of Japan: Part II. GIS-based susceptibility mapping with comparisons of results from two methods and verifications

Slope instability research and susceptibility mapping is a fundamental component of hazard management and an important basis for provision of measures aimed at decreasing the risk of living with landslides. On this basis, this paper presents the result of a comprehensive study on slope stability analyses and landslide susceptibility mapping carried out in part of Sado Island of Japan. Various types of landslides occurred in the island throughout history. Little is known about the triggering factors and severity of old landslides, but for many of the recent slope failures, the slope characteristics and stratigraphy are such that ground surfaces retain water perennially and landslides occur when additional moisture is induced during rainfall and snowmelt. A range of methods are available in literature for preparation of landslide susceptibility maps. In this study we used two methods namely, the analytical hierarchy process (AHP) and logistic regression, to produce and later compare two susceptibility maps. AHP is a semi-qualitative method, which involves a matrix-based pair-wise comparison of the contribution of different factors for landsliding. Logistic regression on the other hand promotes a multivariate statistical analysis with an objective to find the best-fitting model that describes the relationship between the presence or absence of landslides (dependent variable) and a set of causal factors (independent parameters). Elevation, lithology and slope gradient were casual factors in this study. The determinations of factor weights by AHP and logistic regression were preceded by the calculation of class weights (landslide densities) based on bivariate statistical analyses (BSA). The differences between the AHP derived susceptibility map and the logistic regression counterpart are relatively minor when broad-based classifications are considered. However, with an increase in the number of susceptibility classes, the logistic regression map gave more details but the one derived by AHP failed to do so. The reason is that the majority of pixels in the AHP map have high values, and an increase in the number of classes gives little change in the spatial distribution of susceptibility zones in the middle. To verify the practicality of the two susceptibility maps, both of them were compared with a landslide activity map containing 18 active landslide zones. The outcome was that the active landslide zones do not completely fit into the very high susceptibility class of both maps for various reasons. But 70% of these landslide zones fall into the high and very high susceptibility zones of the AHP map while this is 63% in the case of logistic regression. This indicates that despite the skewed distribution of susceptibility indices, the AHP map was better to capture the reality on the ground than the logistic regression equivalent.

Effectiveness of different methods of health education: A comparative assessment in a scientific conference

BackgroundEvery individual mode of health education has its own merits, drawbacks as well as their own sphere of effectiveness. A specific mode of communication is more useful in a specific setting on a specific group than others. To search for optimum mode of communication for a specific audience is a major area of research in health education. The issue of imparting health education to a gathering of educated people, representing different fields of knowledge has remained a relatively less lighted aspect of health education research. In this backdrop this study was initiated for making a comparative assessment of different methods of dissemination of health education among educated people.MethodsA cross-sectional interviewer administered questionnaire survey was conducted involving 142 randomly selected subjects during the last session of a five-day conference having health as main theme when the opinion of the delegates regarding different communication methods was asked for. Collected data was analyzed not only to find out the optimum mode of education dissemination in such a setting but also to find the contribution of different factors in the preferences of the study subjects.ResultsThe participants opted more (60%) for focused programs of smaller audience (sectional program). In both broad area (main program) and focused area programs (sectional), the participants preferred lectures (62% and 65.7% respectively). Specific topics were preferred both in lectures (67.6%) and symposia (57.7%). In the exhibition, exhibits seemed to be more attractive (62%) than the posters. Qualification has emerged to be a contributing factor in peoples' choice towards sectional programme and also in their affinity to symposia. Increased age was a significant contributor in participants' preference towards specific topics. Physical barriers of communication appeared to be a problem in the main program as well as in the exhibition. Lack of coherence among the speakers was reported (69%) to be a major reason for which symposia was not preferred.ConclusionThis study concluded that while planning for health education dissemination in an educated group a focused programme should be formulated in small groups preferably in the form of lectures on specific topics, more so while dealing with participants of higher age group having higher educational qualification.

β‐Hairpin formation in aqueous solution and in the presence of trifluoroethanol: A 1H and 13C nuclear magnetic resonance conformational study of designed peptides

In order to check our current knowledge on the principles involved in beta-hairpin formation, we have modified the sequence of a 3:5 beta-hairpin forming peptide with two different purposes, first to increase the stability of the formed 3:5 beta-hairpin, and second to convert the 3:5 beta-hairpin into a 2:2 beta-hairpin. The conformational behavior of the designed peptides was investigated in aqueous solution and in 30% trifluoroethanol (TFE) by analysis of the following nuclear magnetic resonance (NMR) parameters: nuclear Overhauser effect (NOE) data, and C(alpha)H, (13)C(alpha), and (13)C(beta) conformational shifts. From the differences in the ability to adopt beta-hairpin structures in these peptides, we have arrived to the following conclusions: (i) beta-Hairpin population increases with the statistical propensity of residues to occupy each turn position. (ii) The loop length, and in turn, the beta-hairpin type, can be modified as a function of the type of turn favored by the loop sequence. These two conclusions reinforce previous results about the importance of beta-turn sequence in beta-hairpin folding. (iii) Side-chain packing on each face of the beta-sheet may play a major role in beta-hairpin stability; hence simplified analysis in terms of isolated pair interactions and intrinsic beta-sheet propensities is insufficient. (iv) Contributions to beta-hairpin stability of turn and strand sequences are not completely independent. (v) The burial of hydrophobic surface upon beta-hairpin formation that, in turn, depends on side-chain packing also contributes to beta-hairpin stability. (vi) As previously observed, TFE stabilizes beta-hairpin structures, but the extent of the contribution of different factors to beta-hairpin formation is sometimes different in aqueous solution and in 30% TFE.

Fertility in Marriage and Cohabitation: A Switching Regression Analysis

Little is known about why cohabiting couples have fewer children than married couples. We explore the factors that explain the difference in fertility between these two groups using a switching regression analysis, which enables us to quantify the contribution of different factors through a decomposition of the difference. We find that married couples have more children than cohabiting couples primarily because marriage provides stronger incentives for specialization in household production. Unobserved self-selection plays a less important role.

Metabolic syndrome and coronary artery disease: Is there a gender specific effect?

Introduction Clustering of cardiovascular risk factors is observed in metabolic syndrome (MS), but the relative contribution of different factors to determine outcomes remains largely unknown. We investigated the influence of gender in the effect of MS in coronary vascular lesions in 385 patients who underwent first time coronary artery disease (CAD) assessment through coronary angiography. Materials and methods Patients were stratified in two groups: metabolic syndrome (MS, N = 190) and non-metabolic syndrome (NMS, N = 195), according to standard criteria. Two vascular scores related to extension and severity of vascular lesions were determined by systematic analysis of 20 coronary segments. Results and conclusions MS was more prevalent in females (58.7 vs. 39.7%, p = 0.0005) and hypertension and low-HDL were the leading prevalent factors in the MS group. Scores for extension and severity of lesions were higher in the MS than in the NMS group (2.10 ± 1.75 vs. 1.75 ± 1.58; p = 0.01, and 1.49 ± 1.29 vs. 1.25 ± 1.15; p = 0.03, respectively). The impact of MS in CAD scores was more pronounced in females (OR 2.2, 95% CI 1.1–4.3, p = 0.02) than in males (OR 1.5, 95% CI 0.8–2.7, p = 0.17). Non-HDL cholesterol was the only risk factor influencing the scores in a gender specific manner, showing an increased impact in the female gender. Normal coronary angiograms were more frequent in females ( p = 0.0001), especially in NMS. Collectively, these data suggest that MS is related to higher extension and severity of vascular lesions in this population regardless of gender but lipids and anthropometric parameters may differentially modulate the MS effect in a particular gender.

Developmental and cellular factors underlying corneal epithelial dysgenesis in the Pax6+/− mouse model of aniridia

Heterozygosity for a PAX6 deficiency ( PAX6 +/− ) results in low levels of the PAX6 transcription factor and causes aniridia. Corneal changes in aniridia-related keratopathy (ARK) include peripheral pannus and epithelial abnormalities, which eventually result in corneal opacity and contribute to visual loss. The corneal abnormalities of Pax6 +/− mice provide an excellent model for the corneal changes seen in PAX6 +/− humans. The aim of the present study was to investigate the contributions of different factors (including altered cell proliferation, abnormal epithelial differentiation and incursion of the conjunctival epithelium) that may underlie the pathogenesis of the corneal changes caused by low levels of Pax6 in heterozygous Pax6 +/Sey-Neu ( Pax6 +/− ) mice. BrdU incorporation showed enhanced proliferation of Pax6 +/− corneal epithelium compared to wild-type controls and analysis of p63 (a marker of high proliferative potential) revealed a slight increase in frequency of p63-positive basal corneal epithelial cells in Pax6 +/− mice. Immunohistochemical investigation of K12 (a Pax6-regulated marker of corneal epithelial differentiation) in 2–52-week-old mice showed that K12 expression was delayed and down-regulated in the Pax6 +/− corneal epithelium, implying that differentiation of the Pax6 +/− corneal epithelium was delayed and abnormal. Goblet cells were identified within the peripheral corneal epithelium of the Pax6 +/− eyes, but some were surrounded by cells expressing K12, suggesting they may have arisen in situ in the corneal epithelium. These findings suggest that low levels of Pax6 may be directly responsible for failure or delay of proper differentiation of the corneal epithelial cells, but the proliferative component of the mutant epithelium is probably not impaired. This abnormal differentiation suggests that ARK is not entirely attributable to a limbal stem cell deficiency.

Factors Motivating Software Piracy: A Longitudinal Study

The objective of this paper is to gain a better understanding of factors influencing software piracy. A model explaining the contribution of different factors to software piracy intention and its subsequent effect on actual software piracy is constructed based on established theories of human behavior. The model is then tested empirically in a longitudinal study with a survey. Findings show that social factors and beliefs concerning consequences of software piracy have significant effects on software piracy intentions. The data also show that while habits and facilitating conditions were significantly related to actual piracy behavior, intentions did not necessarily lead to the actual act of software piracy. The implications of the findings to research and practice are discussed.

The influence of factors identified in adolescence and early adulthood on social class inequities of musculoskeletal disorders at age 30: a prospective population-based cohort study

Social class inequities have been observed for most measures of health. A greater understanding of the relative importance of different explanations is required. In this prospective population-based cohort study we explored the contribution of factors, ascertained at different stages between adolescence and early adulthood, to social class inequities in musculoskeletal disorders (MSD) at age 30. We used data from 547 men and 497 women from a town in north Sweden who were baseline examined at age 16 and followed up to age 30. Using logistic regression models, we estimated the unadjusted odds ratios (OR) for MSD for blue-collar versus white-collar workers in men and women separately. We assessed the contribution of different factors identified between adolescence and early adulthood by comparing the unadjusted OR for social class differences with OR adjusted for these explanatory factors. We found significant class differences at age 30 with higher MSD among blue-collar workers (OR = 2.03 in men [95% CI: 1.42, 2.90] and 1.98 in women [95% CI: 1.29, 3.02]). After adjustment for explanatory factors, class differences decreased and were no longer significant, with OR of 1.20 in men (95% CI: 0.76, 1.95) and 1.18 in women (95% CI: 0.69, 2.03). School grades at age 16; being single and alcohol consumption at age 21; having children, restricted financial resources, physical activity, alcohol consumption, smoking, and working conditions at age 30 were important for men; parents' social class, school grade, smoking and physical activity at age 16; being single at age 21; and working conditions at age 30 were important for women. The accumulation of adverse behavioural and social circumstances from adolescence to early adulthood may be an explanation for the class differences in MSD at age 30. Interventions aimed at reducing health inequities need to consider exploratory factors identified at early and later stages in life, also including structural determinants of health.

Cell-surface alterations in class IIa bacteriocin-resistant Listeria monocytogenes strains.

Strains of the food-borne pathogen Listeria monocytogenes, showing either intermediate or high-level resistance to class IIa bacteriocins, were investigated to determine characteristics that correlated with their sensitivity levels. Two intermediate and one highly resistant spontaneous mutant of L. monocytogenes B73, a highly resistant mutant of L. monocytogenes 412, and a highly resistant, defined (mptA) mutant of L. monocytogenes EGDe were compared with their respective wild-type strains in order to investigate the contribution of different factors to resistance. Decreased mannose-specific phosphotransferase system gene expression (mptA, EIIAB(Man) component) was implicated in all levels of resistance, confirming previous studies by the authors' group. However, a clear correlation between d-alanine content in teichoic acid (TA), in particular the alanine : phosphorus ratio, and a more positive cell surface, as determined by cytochrome c binding, were found for the highly resistant strains. Furthermore, two of the three highly resistant strains showed a significant increase in sensitivity towards d-cycloserine (DCS). However, real-time PCR of the dltA (d-alanine esterification), and dal and ddlA genes (peptidoglycan biosynthesis) showed no change in transcriptional levels. The link between DCS sensitivity and increased d-alanine esterification of TA may be that DCS competes with alanine for transport via the alanine transporter. A possible tendency towards increased lysinylation of membrane phospholipid in the highly resistant strains was also found. A previous study reported that cell membranes of all the resistant strains, including the intermediate resistant strains, contained more unsaturated phosphatidylglycerol, which is an indication of a more fluid cell membrane. The results of that study correlate with the possible lysinylation, decreased mptA expression, d-alanine esterification of TA and more positive cell surface charge found in this study for resistant strains. The authors' findings strongly indicate that all these factors could contribute to class IIa bacteriocin resistance and that the combination and contribution of each of these factors determine the level of bacteriocin resistance.

CASE Tools Usage and Impact on System Development Performance

Research results concerning the use of computer-aided software engineering (CASE) tools and their impact on system development performance have been largely contradictory. Our objective in this study was to gain a better understanding of factors influencing CASE tools use and to explore the relation between the degree of their use and the resulting system development performance. We constructed a model explaining the contribution of different factors to CASE tools use and its subsequent effect on system development performance based on sound theories of human behavior. We then tested the model empirically with a survey. Data collected from 290 organizations showed that facilitating conditions (e.g., management support, internal expertise, established norms and standards), habits (i.e., where CASE tools use is routine and not consciously considered), and beliefs concerning improvements in the maintainability of systems developed with CASE tools have significant effects on CASE tools use. The data also showed that CASE tools have a significant effect on all performance aspects considered in our study, that is, systems development process (control and efficiency) as well as the product (quality and maintainability).

Incidence and factors influencing on Helicobacter pylori infection recurrence

a) To determine the rate of H. pylori reinfection after successful eradication in a 4-year follow-up study; and b) To evaluate the contribution of different factors in the infection relapse. A total of 208 patients (age range 18-81 years; average 50 years; 87 women) who had been successfully treated for H. pylori infection were included. Annually, urea breath test was assessed to determine H. pylori status after eradication. Age, sex, rural/urban environment, smoking habit, treatment regimens against H. pylori and urea breath test values were evaluated. reinfection occurred in 9,6% of patients observed, 6,7% (14/208) in the first year, 1,9% (4/208) in the second year, 1% (2/208) in the third and 0% in the forth. Risk factors for infection recurrence were younger age and higher values of urea breath test in the multivariante analysis. annual reinfection rate was 2,4 pacients-year. Younger patients and higher values of urea breath test were factors associated with a higher rate of reinfection relapse. Annually, urea breath test should be performed to detect reinfection in order to avoid ulcer complications.

The relative contributions of tree improvement and cultural practice toward productivity gains in Eucalyptus pulpwood stands

Increasing yield per hectare and associated reduction in the unit cost of wood is an important component of sustained global competitiveness for forest products exported from South Africa. The genetic improvement of planting stock and maximising growth through cultural practice are two strategies for achieving higher yield. The aim of this study is to increase understanding of the interactions between intensive levels of silvicultural management and the deployment of improved genotypes of a number of commercial eucalypt species across a range of sites with different productivity classifications. To demonstrate the relative contributions of different factors associated with productivity gains, five trials of standard design (2×2×2×2 factorial) were planted on five different sites. For each trial and for each factor, a treatment that would exhibit superior productivity was deliberately chosen over a second treatment representing inferior but not uncommon operational practice. The factors tested at each site were species (first choice for the site relative to a sub-optimum second choice), genetic level (unimproved or land-race material relative to first- or second-generation material), planting density (1111 or 1667 stems per ha) and silvicultural intensity (“high” or “low”). An ANOVA for volume per hectare at age two and a half years confirmed significant productivity improvements for the main factors across site productivities and species. Silvicultural treatments were the largest contributors to productivity differences. When measured at this age, achieving high stocking, fertilising and/or maintaining adequate weed control influenced stand productivity to a greater extent than deploying improved material and matching the correct species to the site. On all sites a lack of interaction between factors predominated. This means that the productivity gains associated with each factor are additive.

Changes in erythrocyte microrheology in patients with psoriasis.

Erythrocyte deformability (ED), the ability of red blood cells to change shape during flow in the microcirculation, is the basic rheological property of erythrocytes. It is determined by the surface area to volume ratio, viscoelastic properties of the membrane, and intracellular viscosity. The aim of the present study was to determine changes in erythrocyte microrheology in patients with psoriasis. The whole red cell deformability was measured by flow-channel diffractometry. To assess the contribution of different factors influencing changes in ED, measurements were also made of the biophysical state of the phospholipid bilayer, using an osmotic haemolysis technique, and internal viscosity, using electron paramagnetic resonance spectroscopy. The results showed a significant decrease in ED in patients with psoriasis in comparison with controls, and suggested that the main cause of this may be alterations in intracellular viscosity and membrane viscoelastic behaviour.

Prognostic significance of preoperative factors in localized prostate carcinoma treated with radical prostatectomy: importance of percentage of biopsies that contain tumor and the presence of biopsy perineural invasion.

Predicting outcome for men with clinically localized prostate carcinoma treated with curative intent remains imprecise and further evaluation of accepted and potential predictive factors is needed. The authors studied 696 men with localized prostate carcinoma diagnosed on transrectal biopsy and treated with radical prostatectomy at one institution between 1986 and 1999 to determine the relation between putative pretreatment prognostic factors and disease-free survival. Clinical stage, Gleason score, perineural invasion, number of biopsies containing tumor, and serum prostate specific antigen (PSA) were evaluated as predictors of extracapsular extension, seminal vesicle involvement, lymph node metastases, and surgical margin involvement as well as outcome after surgery. Kaplan-Meier method and Cox regression analyses were used to evaluate the contribution of different factors to adverse pathologic features and relapse. At mean follow-up of 56.9 months (range, 1.0-177.9 months; median, 54.9 months), 26.1% (182 of 696 patients) of patients had developed a disease recurrence. Pretreatment serum PSA concentration, biopsy Gleason score, and clinical stage as well as number of biopsies involved with tumor as a percentage of the total number obtained were found to be independent predictors of outcome. In patients with PSA > 10 ng/mL, biopsy perineural invasion and percentage of biopsies containing tumor were found to independently predicted disease recurrent. Increased number of biopsies involved with tumor independently predicted extracapsular extension, margin involvement, seminal vesicle, and lymph node involvement. This study demonstrated that the proportion of prostate biopsy cores containing tumor is an independent predictor of outcome after subsequent radical prostatectomy and suggested that perineural invasion has a predictive role in patients with a preoperative PSA > 10 ng/ml.

Modelling permeation through porous polymeric films for modified atmosphere packaging

The use of perforated packaging films is increasing with the application of modified atmosphere packaging for fresh produce. These films provide high to very high mass exchange rates. However, irrespective of the chemistry of the material, mass transport through such films cannot be described using conventional permeability equations (Henry's plus Fick's laws). Other expressions such as Knudsen's law, gas diffusivities or Poiseuille's hydrodynamic flow can be applicable. The application of these laws is discussed and their corresponding range of validity is provided. These laws were also applied to model experimental permeation rates of oxygen and water and were further used to describe the headspace evolution of two fruit products in modified atmosphere packaging. In the light of these results, the contribution of different factors to the headspace evolution is discussed.

Hypocholesterolemia in children and adolescents with β-thalassemia intermedia

Objectives: To conduct a prospective study to evaluate the lipid profile in children and adolescents with β-thalassemia intermedia and major, and to examine the contribution of different factors to hypocholesterolemia observed in these patients. Study design: Demographic, clinical, and laboratory data were prospectively obtained from patients with β-thalassemia intermedia (n = 9) and major (n = 47). Lipid profiles were also determined in a control group of healthy children (n = 18). Lipid values of β-thalassemics and controls were compared and the relationships between lipid levels and different covariates were determined. Results: β-thalassemia intermedia patients had significantly lower total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) compared with β-thalassemia major and controls (P <.001). With regression analysis, serum lipid levels (TC, HDL-C, and triglycerides) correlated with diagnosis (β-thalassemia major or intermedia) but not with age, sex, hemoglobin, or ferritin. LDL-C was influenced by both diagnosis and ferritin levels. Conclusions: Children and adolescents with β-thalassemia intermedia have significantly lower cholesterol levels than patients with β-thalassemia major. This is related to their disorder and not influenced by age, sex, hemoglobin, or ferritin levels. In these patients, needless investigations for hypolipidemia should be avoided. (J Pediatr 2002;141:543-7)