Bilateral microphthalmos with bilateral orbital cysts: individualising the treatment according to the visual potential. A case report

The case is presented of a 3-month-old infant diagnosed with microphthalmos and orbital cysts. Magnetic Resonance Imaging revealed a bilateral microphthalmia with a moderate right cyst and a severe left cyst. Visual potential of the right eye was uncertain. Non-surgical treatment was decided. At the age of 2 years old, physical examination showed a significant decrease of the cysts and visual acuity of hand movements due to the residual vision of his right eye. Microphthalmos with orbital cyst is a rare congenital anomaly. Cysts tend to enlarge with time. At the moment, no standard protocol for the management of this pathology has been described. Unlike in our patient, visual acuity in these patients is usually of no-light perception. The observation could be an alternative in severe cases, since there is a possibility of spontaneous reduction, displacement, or regression of the cysts.

Post-mortem toxicology in the diagnosis of sudden death in young and middle-aged victims

OBJECTIVE

We aimed to investigate the impact of the toxicological results found in cases of sudden death (SD) and to correlate the clinical, autopsy and genetic findings with the toxicology results.

MATERIALS AND METHODS

Consecutive SD in people aged between 16 and 50 years with medico-legal autopsies and toxicology studies were included over a 3-year period. The comparison between the toxicological data and demographic characteristics, clinical circumstances, autopsy, and genetic results were taken into account.

RESULTS

101 cases were finally included. They were predominately males (84%) and the mean age was 39.8 years. 52 (51.5%) cases had positive toxicological findings and in 25 cases (24.8%), toxic compounds were considered the first cause of death. Ethanol was the most frequently identified agent (69%), following by licit drugs (56%) and drugs of abuse (39%). Cases with positive toxicology were younger than those with negative results (37.9±9.1 vs. 41.9±7.8; p=0.02). Patients with more than 3 comorbidities showed an association with positive toxicological results (n=14 vs. n=3; p=0.017). The genetic study was performed in 70 (69.3%) SD cases. We identified pathogenic or likely pathogenic variants in 17.1% cases and uncertain significance variants in 42.8% cases. 58% of these variants were probably related to the cause of death.

CONCLUSIONS

A large fraction of SD victims had positive toxicological findings and a quarter of deaths were directly caused by toxic substances. The identification of the factors that trigger SD provides a good approach to contribute in avoiding future episodes.

Glycated hemoglobin and sleep apnea syndrome in children: beyond the apnea-hypopnea index

PURPOSE

Snoring and obstructive sleep apnea syndrome (OSA) are frequent conditions in pediatrics. Glycated hemoglobin (Hb_A1C) is a useful homeostatic biomarker of glycemia and may reflect alterations deriving from sleep breathing disorders. The aim of this study was to relate the severity of OSA with blood Hb_A1C levels in children.

METHODS

A descriptive observational study in snoring patients was performed. All patients underwent a sleep study and classified either as simple snorers (apnea-hypopnea index; AHI ≤ 1 episodies/h) or as OSA patients (AHI > 1 episodes/h). In the following morning, a blood glycemic profile (fasting glucose, insulin, Hb_A1C, and the HOMA index) was performed to every individual.

RESULTS

A total of 48 patients were included. Hb_A1C levels were shown to be increased in the moderate OSA (AHI > 5 episodes/h) group (5.05 ± 0.25 vs. 5.24 ± 0.29%; p = 0.019). Significant correlations were found between Hb_A1C values and AHI (r = 0.345; p = 0.016) and also with oxygen desaturation index (r = 0.40; p = 0.005). Correlations remained significant after adjusting by age and body mass index. The AHI-associated change in Hb_A1C was 13.4% (p = 0.011).

CONCLUSIONS

In the pediatric population, Hb_A1C is a biomarker associated with OSA severity, and this relationship is age- and obesity-independent. The fact that this association was observed in snoring patients could help the physician in the distinction between those patients affected with OSA and those with simple snoring. Therefore, Hb_A1C measurement could play a major role in the diagnosis and the management of the syndrome.

Evaluation of emerging contaminants in a drinking water treatment plant using electrodialysis reversal technology

Emerging contaminants (EC) have gained much attention with globally increasing consumption and detection in aquatic ecosystems during the last two decades from ng/L to lower ug/L. The aim of this study was to evaluate the occurrence and removal of pharmaceutically active compounds (PhACs), endocrine disrupting chemicals (EDCs) and related compounds in a Drinking Water Treatment Plant (DWTP) treating raw water from the Mediterranean Llobregat River. The DWTP combined conventional treatment steps with the world's largest electrodialysis reversal (EDR) facility. 49 different PhACs, EDCs and related compounds were found above their limit of quantification in the influent of the DWTP, summing up to a total concentration of ECs between 1600-4200 ng/L. As expected, oxidation using chlorine dioxide and granular activated carbon filters were the most efficient technologies for EC removal. However, despite the low concentration detected in the influent of the EDR process, it was also possible to demonstrate that this process partially removed ionized compounds, thereby constituting an additional barrier against EC pollution in the product. In the product of the EDR system, only 18 out of 49 compounds were quantifiable in at least one of the four experimental campaigns, showing in all cases removals higher than 65% and often beyond 90% for the overall DWTP process.

Nondestructive Detection of White Root Rot Disease in Avocado Rootstocks by Leaf Chlorophyll Fluorescence

White root rot (WRR) disease caused by Rosellinia necatrix is one of the most important threats affecting avocado orchards in temperate regions. In this study, we monitored the progression of WRR disease at the leaf and root levels by the combination of nondestructive chlorophyll fluorescence measurements and confocal laser-scanning microscopy on avocado genotypes susceptible to R. necatrix. Leaf photochemistry was affected at early stages of disease development prior to the appearance of aboveground symptoms, made evident as significant decreases in the trapping efficiency of photosystem-II (F_v'/F_m') and in the steady-state of chlorophyll fluorescence yield (F_s) normalized to the minimal fluorescence yield (F₀) (F_s/F₀). Decreases in F_v'/F_m' and F_s/F₀ were associated with different degrees of fungal penetration, primarily in the lateral roots but not in areas next to the main root collar. Aboveground symptoms were observed only when the fungus reached the root collar. Leaf physiology was also tracked in a tolerant genotype where no changes were observed during disease progression despite the presence of the fungus in the root system. These results highlight the usefulness of this technique for the early detection of fungal infection and the rapid removal of highly susceptible genotypes in rootstock avocado-breeding programs.

Total adult cardiovascular risk in Central America

OBJECTIVE

To evaluate prevalence of cardiovascular risk among adults 40 years and older using population-based samples from six Central American countries.

METHODS

Risk factors were derived from a multi-national cross-sectional survey implemented in 2003-2006, which included a sample of 4 202 participants aged 40 years and older. Charts produced by the World Health Organization and the International Society of Hypertension for the Region of the Americas sub-region B were used to predict risk on the basis of factors including age, sex, blood pressure, total serum cholesterol, smoking status, and diabetes status.

RESULTS

Overall, 85.9% of the population was classified as having < 10% risk for cardiovascular events during the following ten years. The likelihood of being in this risk group decreased with age in both males and females. Four percent of respondents were identified as having > 20% risk. More than 75% of those with a 30-40% risk had previously been identified by health services, and an additional 23% were identified during the study, suggesting they could be diagnosed by opportunistic screening for diabetes, hypertension and hypercholesterolemia. Results of bivariate analysis showed that respondents who were male, older, obese and/or less educated had higher risk for cardiovascular events, but a multivariate analysis including education indicated highest risks for older, obese, and less educated females.

CONCLUSIONS

Measuring cardiovascular disease risk identifies most cases of (or at risk for) diabetes, hypertension and hypercholesterolemia among adults 40 years and older. This strategy can facilitate implementation of control programs and decrease disabilities and premature mortality.

Stress hyperglycaemia in critically ill patients: potential role of incretin hormones; a preliminary study

BACKGROUND

Stress hyperglycaemia is common in the intensive care unit (ICU) setting and has been related to a worst outcome.

OBJECTIVE

The objective was to characterize the association of glucoregulatory hormones, mainly incretins, with the levels of glycaemia, and its relationship with outcome in ICU patients.

METHODS

We prospectively studied 60 patients. Stress hyperglycaemia was diagnosed when glycaemia was < 115 mg/dL. At ICU admission we determined glycaemia, insulin, glucagon, cortisol, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) plasma levels. Groups were compared using Kruskal-Wallis test. The association between glycaemia levels and glucoregulatory hormones was evaluated using linear regression.

RESULTS

Forty-five patients (75%) had hyperglycaemia. We observed no differences in glucoregulatory hormones levels between normo- and hyper- glycaemia groups. Glycaemia levels were not significantly correlated with insulin, glucagon, cortisol or GIP levels, but were correlated with GLP-1 (p = 0.04). GLP-1 was also correlated with cortisol (p = 0.01), but failed to show a significant correlation with insulin, glucagon or GIP levels. Lower levels of plasma GLP-1 were found in patients with stress hyperglycaemia requiring vasoactive support (p = 0.02).

CONCLUSIONS

Glycaemia levels were correlated with GLP-1 levels in ICU patients. GLP-1 levels were also associated with cortisol. Patients with stress hyperglycaemia who required vasoactive support had lower incretin levels compared with those patients with stress hyperglycaemia who were hemodynamically stables. (ClinicalTrials.gov Identifier: NCT01087372).

Development of robust discriminant equations for assessing subtypes of glioblastoma biopsies

Background:

In the preceding decade, various studies on glioblastoma (Gb) demonstrated that signatures obtained from gene expression microarrays correlate better with survival than with histopathological classification. However, there is not a universal consensus formula to predict patient survival.

Methods:

We developed a gene signature using the expression profile of 47 Gbs through an unsupervised procedure and two groups were obtained. Subsequent to a training procedure through leave-one-out cross-validation, we fitted a discriminant (linear discriminant analysis (LDA)) equation using the four most discriminant probesets. This was repeated for two other published signatures and the performance of LDA equations was evaluated on an independent test set, which contained status of IDH1 mutation, EGFR amplification, MGMT methylation and gene VEGF expression, among other clinical and molecular information.

Results:

The unsupervised local signature was composed of 69 probesets and clearly defined two Gb groups, which would agree with primary and secondary Gbs. This hypothesis was confirmed by predicting cases from the independent data set using the equations developed by us. The high survival group predicted by equations based on our local and one of the published signatures contained a significantly higher percentage of cases displaying IDH1 mutation and non-amplification of EGFR. In contrast, only the equation based on the published signature showed in the poor survival group a significant high percentage of cases displaying a hypothesised methylation of MGMT gene promoter and overexpression of gene VEGF.

Conclusion:

We have produced a robust equation to confidently discriminate Gb subtypes based in the normalised expression level of only four genes.

Day-night variations in endothelial dysfunction markers and haemostatic factors in sleep apnoea

Patients with sleep apnoea have a significant alteration in the day-night pattern of myocardial infarction and sudden cardiac death observed in the general population. The aim of this study was to investigate the influence of sleep apnoea on the diurnal variations in various haemostatic parameters (factor VII, von Willebrand factor and plasminogen activator inhibitor (PAI)-1) and markers of endothelial dysfunction (asymmetric dimethylarginine (ADMA) and soluble CD40 ligand (sCD40L)). We studied 26 male patients with obstructive sleep apnoea syndrome (OSAS; 13 patients with severe OSAS (apnoea/hypopnoea index (AHI) >30 events · h(-1)) and 13 patients with mild-to-moderate OSAS (AHI <30 events · h(-1))) and 12 controls of similar body mass index (BMI) and waist circumference. In each subject, six different samples were obtained over 24 h. Although all the markers values tended to be higher in patients with severe OSAS, differences did not reach statistical significance at any time. PAI-1 levels were significantly related to BMI (p<0.001), mean (p<0.001) and minimal (p = 0.047) nocturnal oxygenation saturation. ADMA levels were significantly related to arousal index (p = 0.046). The results of this study suggest that day-night variations in factor VII:antigen (Ag), von Willebrand factor:Ag, PAI-1, sCD40L and ADMA levels may be dependent on either the obesity index or metabolic dysfunction rather than on sleep apnoea alone.

Free fatty acids and the metabolic syndrome in patients with obstructive sleep apnoea

Obesity and metabolic syndrome (MS) occur frequently in patients with obstructive sleep apnoea syndrome (OSAS). We hypothesised that circulating free fatty acids (FFAs) are elevated in OSAS patients independently of obesity. This elevation may contribute to the development of MS in these patients. We studied 119 OSAS patients and 119 controls. Participants were recruited and studied at sleep unit of our institution (Hospital Universitari Son Dureta, Palma de Mallorca, Spain) and were matched for sex, age and body mass index (BMI). The occurrence of MS was analysed by clinical criteria. Serum levels of FFAs, glucose, triglycerides, cholesterol, high-density lipoprotein-cholesterol, aspartate aminotransferase, alanine aminotransferase, γ-glutamyltransferase, C-reactive protein and 8-isoprostanes were determined. Prevalence of MS was higher in OSAS than in the control group (38 versus 21%; p=0.006). OSAS patients had higher FFAs levels than controls (mean±sd 12.2±4.9 versus 10.5±5.0 mg·dL(-1); p=0.015). Among subjects without MS, OSAS patients (OSAS+ MS-) showed higher levels of FFAs than controls (OSAS- MS-) (11.6±4.7 versus 10.0±4.4 mg·dL(-1); p=0.04). In a multiple regression model, after adjustment for age, sex, BMI and the presence of MS, FFAs were significantly associated with apnoea/hypopnoea index (p=0.04). This study shows that FFAs are elevated in OSAS and could be one of the mechanisms involved in the metabolic complications of OSAS.

Enhancing global capacity in the surveillance, prevention, and control of chronic diseases: seven themes to consider and build upon

BACKGROUND

Chronic diseases are now a major health problem in developing countries as well as in the developed world. Although chronic diseases cannot be communicated from person to person, their risk factors (for example, smoking, inactivity, dietary habits) are readily transferred around the world. With increasing human progress and technological advance, the pandemic of chronic diseases will become an even bigger threat to global health.

METHODS

Based on our experiences and publications as well as review of the literature, we contribute ideas and working examples that might help enhance global capacity in the surveillance of chronic diseases and their prevention and control. Innovative ideas and solutions were actively sought.

RESULTS

Ideas and working examples to help enhance global capacity were grouped under seven themes, concisely summarised by the acronym "SCIENCE": Strategy, Collaboration, Information, Education, Novelty, Communication and Evaluation.

CONCLUSION

Building a basis for action using the seven themes articulated, especially by incorporating innovative ideas, we presented here, can help enhance global capacity in chronic disease surveillance, prevention and control. Informed initiatives can help achieve the new World Health Organization global goal of reducing chronic disease death rates by 2% annually, generate new ideas for effective interventions and ultimately bring global chronic diseases under greater control.

Insulin resistance and daytime sleepiness in patients with sleep apnoea

BACKGROUND

Excessive daytime sleepiness (EDS), obesity and insulin resistance (IR) occur frequently in patients with obstructive sleep apnoea syndrome (OSAS). We hypothesised that in these patients, EDS is a marker of IR, independent of obesity.

METHODS

We studied 44 patients with OSAS (22 with and 22 without EDS) matched for age (+/-5 years), body mass index (BMI +/-3 kg/m(2)) and severity of OSAS (as determined by the apnoea-hypopnoea index (AHI)), and 23 healthy controls. Patients (n = 35) were re-examined after 3 months of effective therapy with continuous positive airway pressure (CPAP). EDS was assessed by both subjective (Epworth Sleepiness Scale) and objective (Multiple Sleep Latency Test) methods. IR was determined by the HOMA index. Serum levels of glucose, triglycerides, cholesterol, cortisol, insulin, thyrotropin, growth hormone and insulin-like growth factor I (IGF-I) were also determined.

RESULTS

Despite the fact that age, BMI and AHI were similar, patients with EDS had higher plasma levels of glucose (p<0.05) and insulin (p<0.01), as well as evidence of IR (p<0.01) compared with patients without EDS or healthy controls. CPAP treatment reduced cholesterol, insulin and the HOMA index and increased IGF-1 levels in patients with EDS, but did not modify any of these variables in patients without EDS.

CONCLUSION

EDS in OSAS is associated with IR, independent of obesity. Hence EDS may be a useful clinical marker to identify patients with OSAS at risk of metabolic syndrome.

Waist circumference, BMI and the prevalence of self-reported diabetes among the elderly of the United States and six cities of Latin America and the Caribbean

Using data from the Salud Bienestar y Envejecimiento (SABE) project and the U.S. National Health and Nutrition Examination Survey (NHANES 1999-2004), we examined the prevalence of obesity and diagnosed diabetes among older adults in the Americas; we also examined the association of age, sex, level of education, weight status, waist circumference, smoking, and race/ethnicity with diabetes among older adults. The prevalence of diagnosed diabetes was highest in the US Blacks and Mexican Americans, followed by Bridgetown and Mexico City (22% for each) and lowest in Santiago, Montevideo, Havana, and US Whites (13-15%). Diagnosed diabetes was significantly associated with BMI among participants from Bridgetown, Sao Paulo, and the three US ethnic groups, while it was associated with waist circumference in all sites except Mexico City. Our findings suggest major geographical and ethnic variation in the prevalence of diagnosed diabetes among older adults. Waist circumference was more consistently associated with the prevalence of diagnosed diabetes than BMI. Higher prevalences of diabetes are found among the elderly of African or Mexican descent in the United States and in other countries of the Americas when compared to the prevalence among whites in the United States and in other Latin American countries with populations of predominant Western European descent.

Prostaglandin D synthase (β trace) levels in sleep apnea patients with and without sleepiness

BACKGROUND

Excessive daytime sleepiness (EDS) occurs often in patients with obstructive sleep apnea syndrome (OSAS). However, not all patients present EDS. We hypothesized that the prostaglandin D2 system (PGD2) may be involved in the pathogenesis of EDS associated with OSAS.

METHODS

We measured the levels of lipocalin-type PGD synthase (L-PGDS), the enzyme that produces PGD2, in the serum of 47 patients with OSAS (26 with and 21 without EDS) and 18 healthy controls.

RESULTS

Patients with EDS had higher levels of L-PGDS (0.73+/-0.06 mg/L) than patients without EDS (0.58+/-0.03 mg/L, p<0.05) and controls (0.62+/-0.02 mg/L, p<0.05). L-PGDS levels in patients without EDS and controls were similar.

CONCLUSION

The increased levels of circulating L-PGDS detected in OSAS patients with EDS suggest a possible role of the prostaglandin D system in the pathophysiology of daytime sleepiness in these patients.

beta3-Adrenergic receptor Trp64Arg polymorphism and increased body mass index in sleep apnoea

Obesity is an important risk factor for obstructive sleep apnoea syndrome (OSAS), insulin resistance and cardiovascular disease. The substitution of tryptophan 64 with arginine (Trp64Arg) polymorphism (Arg variant) of the beta(3)-adrenergic receptor (ADRB3) has been associated with obesity. In this study, the prevalence of the Trp64Arg ADRB3 polymorphism in a large group of patients with OSAS and its association with body mass index (BMI), insulin resistance and hypertension were evaluated. ADRB3 genotype was determined in 387 patients with OSAS and 137 healthy subjects recruited from three Spanish tertiary hospitals. The distributions of the ADRB3 genotypes were similar in OSAS and controls, and, in a multivariate model, the risk of OSAS was not associated with the presence of the Arg variant of the ADRB3 gene. However, BMI was higher in those patients with OSAS who carried this genetic variant than in those with the Trp variant. Furthermore, a linear trend for higher BMI was found in those with the Arg variant (56, 75 and 100% for Trp/Trp, Trp/Arg and Arg/Arg, respectively). Insulin resistance, blood pressures and serum levels of lipids and glucose were not associated with the presence of the Arg variant of the ADRB3 gene. The presence of the arginine 64 allele of the beta(3)-adrenergic receptor gene does not increase the risk of obstructive sleep apnoea syndrome, but is associated with the development of obesity in those patients who suffer obstructive sleep apnoea syndrome.

Daytime sleepiness and polysomnographic variables in sleep apnoea patients

Excessive daytime sleepiness (EDS) is not invariably present in patients with obstructive sleep apnoea syndrome (OSAS). The aim of the present study was to investigate polysomnographic determinants of EDS in patients with OSAS. EDS was assessed using the Epworth Sleepiness Scale (ESS) and the multiple sleep latency test (MSLT). Patients showed EDS whenever the ESS score was >10 and the MSLT score <5 min. Absence of EDS was defined as having an ESS score of <10 and an MSLT score of >10 min. In total, 23 male patients with EDS (mean+/-sd ESS and MSLT score 17+/-3 and 4+/-1 min, respectively) and 17 without EDS (ESS and MSLT score 5+/-2 and 16+/-3 min, respectively), were studied. Both groups exhibited a similar apnoea/hypopnoea index (62+/-18 versus 60+/-20 events.h(-1)). Patients with EDS exhibited shorter sleep latency (11+/-16 versus 18+/-18 min) and greater sleep efficiency (90+/-7 versus 82+/-13%) than those without EDS. Patients with EDS showed lower oxygenation (lowest arterial oxygen saturation 69+/-12 versus 79+/-8%; mean arterial oxygen saturation 87+/-6 versus 90+/-5%). Sleep stage distribution and arousal index did not differ between the groups. Patients with obstructive sleep apnoea syndrome and excessive daytime sleepiness are characterised by shorter sleep latency, increased sleep efficiency and worse nocturnal oxygenation than those without excessive daytime sleepiness. Nocturnal hypoxaemia can be a major determinant of excessive daytime sleepiness in patients with obstructive sleep apnoea syndrome.

A cohort analysis of type 1 diabetes mortality in Havana and Allegheny County, Pittsburgh, PA

OBJECTIVE

To examine the mortality of type 1 diabetes (T1D) in two countries with very different health care systems using two population-based registries of childhood-onset T1D one in Havana (HA), Cuba, and the other in Allegheny County (AC), USA.

RESEARCH DESIGN AND METHODS

Cases diagnosed with T1D between 1965 and 1980 in HA and between 1965 and 1979 in AC were included. Follow-up started with diagnosis in each individual and ended as of 1 January 1991, or with death. Life-table analyses were used to examine the mortality rates in both populations by duration of diabetes.

RESULTS

Cumulative mortality by January 1991 in HA (14% in males and females, respectively) was higher than in AC (7% in males and 9% in females) for both genders (males, p=0.0005; females, p=0.0491). Mortality rates were considerably higher in HA for both men and women than in AC however, among females confidence intervals overlapped. Overall mortality rate for Caucasians (AC) was significantly lower than that for African-Americans (AC) or Hispanics (HR). An analysis of causes of death showed a greater proportion of deaths attributed to nephropathy (48.6%) in HA while acute complications (36%) and infections (27%) were more frequent in AC.

CONCLUSIONS

This study shows a two-fold greater mortality among people with childhood-onset T1D in Havana, Cuba, than in Allegheny, USA. Different strategies may be needed to increase survival among those with type 1 diabetes in the USA and Cuba.

Antioxidant status in patients with sleep apnoea and impact of continuous positive airway pressure treatment

The episodes of hypoxia/re-oxygenation associated with the respiratory disturbances observed in patients with obstructive sleep apnoea syndrome (OSAS) may induce the generation of oxygen free radicals. Indeed, several studies suggest that OSAS is associated with oxidative stress. The present study tested the hypothesis that patients with OSAS have an alteration in antioxidant defences. The plasma levels of total antioxidant status (TAS), glutathione peroxidase (GPX), gamma-glutamyltransferase (GGT), vitamins A, E, B12 and folate, and homocysteine were determined in 47 patients with OSAS and 37 healthy subjects. Of these, 27 patients who used continuous positive airway pressure (CPAP) for >4 h.night-1 were re-examined 12 months later. Patients with OSAS had lower TAS (1.4+/-0.16 versus 1.50+/-0.10 mmol.L-1), vitamin A (64+/-19 versus 74+/-17 microg.dL-1) and vitamin E levels (1,525+/-499 versus 1,774+/-503 microg.dL-1), and increased values of GGT (42+/-22 versus 32+/-16 U.L-1) than controls. There was no difference between groups in GPX, homocysteine, vitamin B12 and folate plasma levels. CPAP treatment normalised the levels of TAS (1.50+/-0.13 mmol.L-1) and the activity of GGT (30+/-14 U.L-1) without any influence on vitamins levels. In conclusion, the results indicate that patients with obstructive sleep apnoea syndrome have a decreased antioxidant capacity that is partially reversed by continuous positive airway pressure treatment.

Plasminogen activator inhibitor-I (PAI-I) polymorphisms in patients with obstructive sleep apnoea

Cardiovascular diseases are frequent among patients with the obstructive sleep apnoea syndrome (OSAS), The aetiopathogenesis of this association is unclear. Type 1 plasminogen activator inhibitor (PAI-1) is one of the primary regulators of the fibrinolytic system. A reported association between PAI-1 activity and an insertion/deletion polymorphism (4G/5G) in the promoter region of the PAI-1 gene suggests a critical role for this genomic region in the pathogenesis of several cardiovascular diseases. In this study, we determined the prevalence of this polymorphism in patients with OSAS and in healthy control subjects. The 4G/5G polymorphism in the promoter region of the PAI-1 gene was determined in 78 male patients with severe OSAS (56 +/- 2 apnoeas per hour) and in 70 healthy male, non-smoker volunteers of similar age, without personal or familial history of cardiovascular disease. The frequency ofthe 4G/4G, 4G/5G and 5G/5G genotypes in patients with OSAS (18%, 62%, 19%, respectively) was not significantly different from that seen in healthy subjects (16%, 60%, 24% P=NS). These results show that the distribution of the 4G/5G polymorphism in the promoter region ofthe PAI-1 gene in patients with OSAS is similar to that observed in healthy subjects. This observation suggests that the PAI-1 polymorphism has no relationship with the increased risk of cardiovascular diseases seen in patients with OSAS.

Diabetes in Bolivia

OBJECTIVE

To measure the prevalence of diabetes mellitus (DM), hypertension, obesity, and related risk factors in major cities in Bolivia.

METHODS

A population-based survey was conducted in four Bolivian cities: La Paz, El Alto, Santa Cruz, and Cochabamba. The total sample size was chosen to be 2,948 persons. The overall response rate was 86%, with the rate varying somewhat among the four cities. DM was diagnosed through an oral glucose tolerance test (OGTT) 2 hours after an overload of 75 grams of glucose, using World Health Organization criteria.

RESULTS

The overall prevalence of DM in the four urban areas combined was 7.2% (95% confidence interval (CI): 6.2%-8.3%) and of impaired glucose tolerance (IGT) was 7.8%. A total of 73.1% (95% CI: 65.0%-81.0%) of those previously diagnosed with DM and 73.7% (95% CI: 61.0%-86.4%) of newly diagnosed cases were overweight, according to measurements of body mass index. Hypertension was found in 36.5% (95% CI: 27.6%-45.5%) of known diabetics and in 36.6% (95% CI: 23.0%-50.1%) of newly diagnosed cases, compared to only 15.9% (95% CI: 14.3%-17.5%) among people without DM. The disease was most common among older persons and those with little education.

CONCLUSIONS

Diabetes is a genuine public health problem in Bolivia. Further, the high prevalence of IGT that was found suggests that diabetes prevalence will increase in the near future in the country unless prevention strategies are implemented.

[An intervention to improve diabetes control in Chile]

OBJECTIVE

Previous research has shown that controlling blood glucose improves short-term and long-term outcomes among patients who have either type 1 or type 2 diabetes. The objective of this study was to investigate, in a developing country, the effectiveness of an intervention that included patient education, self-monitoring of blood glucose, and determination of the level of glycosylated hemoglobin (HbA1c).

METHODS

The patients were grouped into three categories, taking into account such clinical manifestations as the duration of their diabetes, its treatment, and their hospitalization history. After the inclusion and exclusion criteria were applied, the persons were randomly assigned to two groups. One group (210 patients) received the educational intervention, and the control group (206 patients) received customary care. The intervention group received educational information needed for self-monitoring of blood glucose and for the self-evaluation of positive and negative behaviors related to metabolic control of the disease.

RESULTS

The two groups were similar with respect to age (mean of 52.3 and 50.5 years) and to the proportion of patients with type 1 diabetes (13.8% and 16.0%). There were no initial differences in the average concentration of HbA1c in the two groups (8.9% +/- 0.1% and 8.9% +/- 1.4%). A total of 50 persons dropped out of the study, 14.8% of those in the intervention group and 9.2% of those in the control group. In the intervention group, compliance with dietary recommendations increased by 43.5%, from 57.5% at the beginning of the study to 82.5% at the end (P < 0.001); in the control group there was also a change but it was not significant. Although patients with a high initial HbA1c concentration were underrepresented in this study, the average HbA1c concentration declined significantly in the intervention group (-0.4% +/- 1.1%, P = 0.001) but not in the control group (-0.1% +/- 0.1%).

CONCLUSIONS

In one developing country, educating patients about diabetes helped improve metabolic control, a fact that can be attributed mainly to the intervention's positive impact on those persons' diet.

[National campaign to detect suspected diabetes cases in Brazil: a preliminary report]

The Ministry of Health of Brazil is implementing a National Plan for the Reorganization of Health Care for Hypertension and Diabetes Mellitus, with the aim of reducing the morbidity and mortality associated with diabetes. This plan is divided into four stages, one of which was a national campaign to detect suspected diabetes cases that was carried out in March and April 2001. This was the first survey of its kind carried out by public health services in Brazil, and the preliminary results are described in this article. Out of a total of 5,507 participating municipalities, 4,446 of them (81%) submitted data to the Ministry of Health. Twenty million people were tested (71% of the target population), and 3.3 million of them were identified as possibly having diabetes. The campaign will contribute towards restructuring the systematic and resolution-oriented care that the national, public Unified Health System provides to diabetics. The preliminary results confirm that diabetes is one of the main health problems in Brazil. Priority should be given to preventing type 2 diabetes.

Incidence and prevalence of diabetes mellitus in the Americas

OBJECTIVE

To present the incidence and prevalence of diabetes mellitus in the Americas as found through a thorough review of published information on the subject.

METHODS

Data were obtained through a comprehensive review using the MEDLINE and BIREME bibliographical databases. In addition, government publications, conference reports, and meeting documents were identified by contacting government and nongovernmental organizations and other institutions. Incidence and prevalence rates were adjusted by age and sex, when possible, by the direct method using the world Segi population as the standard. The 95% confidence intervals were calculated using the Poisson distribution or the normal distribution.

RESULTS

Diabetes mellitus represents a major public health problem in the Americas, and there is evidence that its prevalence is increasing in some countries.

CONCLUSIONS

Given that most Latin American and Caribbean nations are experiencing a demographic transition, it is expected that the prevalence of diabetes will continue to increase rapidly in the near future. Despite the economic constraints faced by the countries of the Americas, there is a clear need for more efforts in the area of diabetes prevention and control.

Angiotensin converting enzyme in patients with sleep apnoea syndrome: plasma activity and gene polymorphisms

The prevalence of several cardiovascular diseases is increased with obstructive sleep apnoea syndrome (OSAS), due to, as yet, unclear reasons. Angiotensin converting enzyme (ACE) abnormalities have been implicated in the pathogenesis of various cardiovascular diseases. In this study, plasma ACE activity and the distribution of an insertion (I)/deletion (D) polymorphism of the ACE gene were determined in OSAS patients and in healthy controls. A total of 63 patients with OSAS (mean+/-SEM 54.5+/-2.5 apnoea/hypopnoeas.h(-1)) and 32 healthy subjects were studied. To avoid potential confounding factors, patients treated with ACE inhibitors or continuous positive airway pressure were excluded, as well as controls in whom a blood sample was not obtained early in the morning. ACE activity was determined spectrophotometrically in 46 OSAS patients and 25 controls. The I/D ACE polymorphism was determined by polymerase chain reaction in 44 patients and 32 controls. ACE activity was higher in OSAS patients (53.9+/-2.5 IU.L(-1)) than in healthy controls (42.4+/-3.1 IU.L(-1), p<0.01). This was independent of the presence of arterial hypertension. The frequency distribution of the DD, II and ID genotypes in OSAS patients (30%, 16%, 54%, respectively) was not significantly different from that seen in healthy subjects (31%, 28%, 41%, respectively, p=0.356). These results indicate that ACE plasma activity is increased in untreated OSAS patients. This increased activity may contribute to the pathogenesis of the cardiovascular disease in these patients.

Functional analysis of the Neurospora crassa PZL-1 protein phosphatase by expression in budding and fission yeast

The gene pzl-1 from the filamentous fungus Neurospora crassa encodes a putative Ser/Thr protein phosphatase that is reminiscent of the Ppz1/Ppz2 and Pzh1 phosphatases from Saccharomyces cerevisiae and Schizosaccharomyces pombe, respectively. The entire PZL-1 protein, as well as its carboxyl-terminal domain, have been expressed in Escherichia coli as active protein phosphatases. To characterize its cellular role, PZL-1 was also expressed in Sz. pombe and in S. cerevisiae. Expression of PZL-1 in S. cerevisiae from the PPZ1 promoter was able to rescue the altered sensitivity to caffeine and lithium ions of a ppz1 strain. Furthermore, high copy number expression of PZL-1 alleviated the lytic phenotype of a S. cerevisiae slt2/mpk1 mitogen-activated protein (MAP) kinase mutant, similarly to that described for PPZ1, and mimicked the effects of high levels of Ppz1 on cell growth. Expression of PZL-1 in fission yeast from a weak version of the nmt1 promoter fully rescued the growth defect of a pzh1Delta strain in high potassium, but only partially complemented the sodium-hypertolerant phenotype. Strong overexpression of the N. crassa phosphatase in Sz. pombe affected cell growth and morphology. Therefore, PZL-1 appears to fulfil every known function carried out by its S. cerevisiae counterpart, despite the marked divergence in sequence within their NH(2)-terminal moieties.

Abnormal lipid peroxidation in patients with sleep apnoea

The prevalence of cardiovascular diseases is increased in patients with the obstructive sleep apnoea syndrome (OSAS). The fall and rise of arterial oxygenation that follows each apnoea may increase lipid peroxidation and contributes to explaining this association. In the present study, the authors determined lipid peroxidation in patients with OSAS and the effect of treatment with continuous positive airway pressure (CPAP). Fourteen male patients with severe OSAS (59+/-5 apnoea x h(-1)) (+/-SEM) and 13 healthy nonsmoking, male volunteers of similar age were studied. Patients were studied at diagnosis and after treatment with CPAP for more than 1 yr (>4 h x night(-1)). A venous blood sample was obtained early in the morning after fasting all night. In patients with OSAS, a sample before and during sleep was also obtained. Low density lipoprotein (LDL) particles were isolated by sequential ultracentrifugation. Their level of oxidation was determined by the thiobarbituric acid assay (TBARs), and their susceptibility to oxidation by the lag phase measurement. Patients with OSAS showed higher TBARs (28.1+/-2.8 versus 20.0+/-1.8 nmol x malondialdehyde x mgLDL protein(-1), p=0.02) and shorter lag phase values (83.8+/-3.4 versus 99.7+/-3.4 min, p=0.005) than controls. These differences were not due to the smoking status of the patient. Likewise, these values did not change significantly throughout the night yet, the lag phase value was significantly improved by treatment with CPAP (124.9+/-8.5 min; p<0.001). These results indicate that obstructive sleep apnoea syndrome is associated with abnormal lipid peroxidation and that this is improved by chronic use of Continuous positive airway pressure. These results can contribute towards explaining the high prevalence of cardiovascular diseases seen in Obstructive sleep apnoea syndrome.

Rare variants in the promoter of the fragile X syndrome gene (FMR1)

Fragile X syndrome, the most common form of familial mental retardation, is mainly caused by the expansion of an unstable region of CGG repeats in the 5' untranslated region of the FMR1 (Fragile X Mental Retardation-1) gene. Molecular tools to detect an abnormal CGG expansion in FMR1 include Southern blot hybridization and PCR amplification. Southern blotting with the StB12.3 probe and Eco RI/Eag I double digestion is widely used as a routine test for fragile X syndrome diagnosis in laboratories around the world. A patient with mental retardation of unknown origin showed absence of digestion for Eag I due to a -149C-->G substitution in the CpG island of the FMR1 gene, which destroys that restriction enzyme site. Screening for other changes around that region also detected a -154insGGC in a patient with a phenotype highly suggestive of fragile X syndrome but without CGG expansion. Expression studies did not show any abnormal changes in FMR1 function. In summary, we have identified two different changes (a C to G substitution at -149 and a GGC insertion at -154) in the promoter of the FMR1 gene. These are the first variants described in the promoter of the FMR1 gene.

A tomato peroxidase involved in the synthesis of lignin and suberin

The last step in the synthesis of lignin and suberin has been proposed to be catalyzed by peroxidases, although other proteins may also be involved. To determine which peroxidases are involved in the synthesis of lignin and suberin, five peroxidases from tomato (Lycopersicon esculentum) roots, representing the majority of the peroxidase activity in this organ, have been partially purified and characterized kinetically. The purified peroxidases with isoelectric point (pI) values of 3.6 and 9.6 showed the highest catalytic efficiency when the substrate used was syringaldazine, an analog of lignin monomer. Using a combination of transgenic expression and antibody recognition, we now show that the peroxidase pI 9.6 is probably encoded by TPX1, a tomato peroxidase gene we have previously isolated. In situ RNA hybridization revealed that TPX1 expression is restricted to cells undergoing synthesis of lignin and suberin. Salt stress has been reported to induce the synthesis of lignin and/or suberin. This stress applied to tomato caused changes in the expression pattern of TPX1 and induced the TPX1 protein. We propose that the TPX1 product is involved in the synthesis of lignin and suberin.

Single-strand conformation polymorphism analysis in the FMR1 gene

The fragile X syndrome is due to an expansion of the CGG trinucleotide repeat in the FMR1 gene and hypermethylation of its 5' upstream CpG island in about 95% of the cases. The remaining 5% of cases correspond to other molecular alterations in FMR1 gene such as partial or complete deletions, or point mutations within the coding sequence. We selected 31 patients with clinical manifestations of fragile X syndrome, scoring 16 or more in Hagerman's checklist, but without the CGG expansion. We performed single-strand conformation polymorphism analysis using a nonradioactive technique (silver staining) and we detected six anomalous migrations that, by sequence analysis, corresponded to six nucleotide changes. We screened two different populations (control and fragile X) for these changes, and concluded that they correspond to five new polymorphisms within the FMR1 gene and to one possible synonymous mutation.

Metallic fragment deposits during phacoemulsification

PURPOSE

To describe the nature and origin of foreign metallic intraocular bodies appearing after phacoemulsification.

SETTING

Department of Ophthalmology, University Hospital of San Juan, Alicante, Spain.

METHODS

Two metallic particles, 1 extracted during surgery and the other from a patient in whom surgery had been performed, were studied by scanning electronic microscopy and X-ray dispersive energy spectroscopy. Also evaluated were all metallic elements used in phacoemulsification including phaco tips, Sinskey hooks, and handpieces. A morphologic analysis at various magnifications was performed and the composition of the elements studied.

RESULTS

Scanning electronic microscopy showed irregularities of the phaco tip and Sinskey hook after their use. Spectrographic analysis found that the phaco tip was mainly aluminum and titanium; the Sinskey hook, iron, chromium, cobalt, and nickel; the handpiece, iron, chromium, and nickel; and the 2 metallic particles, iron, chromium, and nickel, the same as the handpiece.

CONCLUSION

The metallic particles extracted corresponded to those of the phaco handpiece. Vibration during prolonged use of the phacoemulsifier probably caused these particles to chip off the handpiece.

Mild or absent clinical signs in twin sisters with short-chain acyl-CoA dehydrogenase deficiency

Two HLA-identical twin sisters are reported, of whom one has remained essentially asymptomatic, and an episode of hypotonia and decreased level of conciousness being the only relevant clinical finding in the other. Organic acid-analysis revealed that ethylmalonate was constantly, although sometimes only slightly, increased. No abnormal acylglycines or acylcarnitines could be detected. Enzyme assay in cultured skin fibroblasts confirmed short-chain acyl-CoA dehydrogenase deficiency.

CONCLUSION

The lack of appropriate biochemical markers for this deficiency makes the diagnosis difficult and consequently, the low number of patients described may be the result of underdiagnosis.

A nonsense mutation in the 3-hydroxy-3-methylglutaryl-CoA lyase gene produces exon skipping in two patients of different origin with 3-hydroxy-3-methylglutaryl-CoA lyase deficiency

A novel nonsense mutation associated with the skipping of constitutive exon 2 of the 3-hydroxy-3-methylglutaryl-CoA lyase gene was found in two patients, from Portugal and Morocco, with 3-hydroxy-3-methylglutaric acidemia. By reverse transcriptase PCR and single-strand conformational polymorphism a G-T transversion was located, at nucleotide 109, of the 3-hydroxy-3-methylglutaryl-CoA lyase cDNA, within exon 2. Two mRNAs were produced as a result of this nonsense mutation: one of the expected size that contains the premature stop codon UAA, and the other with a deletion of 84 bp corresponding to the whole of exon 2. This deletion produced the loss of the last seven amino acids of the leader peptide and the first 21 amino acids of the mature protein. The nonsense mutation was found in a purine-rich GGAAG sequence, which is equal to, or similar to, others reported to be exonic splicing enhancers (ESE). We suggest that the nonsense mutation may affect a possible ESE on exon 2, which would hinder the splice site selection and facilitate an aberrant splice with the skipping of this exon. Determination by quantitative PCR shows that the ratio of mRNA with the nonsense mutation to the mRNA with the deletion is approx. 3:1.

Platelet integrin alpha IIb beta 3 (GPIIb-IIIa) is not implicated in the binding of LDL to intact resting platelets

It has been suggested that the fibrinogen receptor (glycoprotein [GP] IIb-IIIa or platelet integrin alpha IIb beta 3) could be the binding site for low-density lipoprotein (LDL); however, recent data do not support this. Furthermore, GPIIb and not the GPIIb-IIIa complex is the main binding protein for lipoprotein(a) [Lp(a)]. In the present study, we have investigated the interaction between Lp(a) particles and platelet LDL binding sites and whether platelet integrin alpha IIb beta 3 is implicated. Displacement experiments showed that 125I-LDL binding to intact resting platelets was inhibited with the same apparent affinity by both unlabeled LDL and apolipoprotein(a)-free lipoprotein particles [Lp(a)-, an LDL-like particle prepared from Lp(a)]. Hill coefficients for displacement curves suggested that a single set of binding sites was involved. In contrast, both native and oxidized Lp(a) particles were unable to inhibit platelet LDL binding. Furthermore, platelets bound 125I-Lp(a)- particles to a class of saturable binding sites numbering approximately 1958 +/- 235 binding sites per platelet with a dissociation constant (Kd) of 48.3 +/- 12 x 10(-9) mol/L. These values were similar to those obtained for LDL. In contrast to Lp(a), evidence indicates that platelet integrin alpha IIb beta 3 was not involved in the interaction of LDL and intact resting platelets. First, specific ligands for platelet integrin alpha IIb beta 3, such as fibrinogen, vitronectin, and fibronectin, were unable to inhibit the binding of LDL to intact resting platelets. Second, similar LDL binding characteristics (Kd and Bmax values) were found in platelets from control subjects and patients with type I and type II Glanzmann's thrombasthenia, characterized by total and partial lack of GPIIb-IIIa and fibrinogen, respectively. Third, polyclonal antibodies against the GPIIb-IIIa complex (edu-3 and 5B12), human antiserums against platelet alloantigens (anti-Baka/B and anti-PLA1/2), anti-integrin subunits (anti-alpha v and anti-beta 3), and a wide panel of monoclonal antibodies (mAbs) against well-known epitopes of GPIIb (M3, M4, M5, M6, and M95-2b) and GPIIIa (P23-7, P33, P37, P40, and P97) did not affect platelet LDL binding. Finally, in contrast to the proaggregatory effect of native and oxidized LDL, both native and oxidized Lp(a) particles caused a significant dose-dependent decrease of collagen-induced platelet aggregation. In conclusion, we demonstrate that neither the GPIIb-IIIa complex nor GPIIb and GPIIIa individually are membrane binding proteins for LDL on intact resting platelets. Lp(a) particles do not interact with platelet LDL binding sites, and their biological response is clearly different from that of LDL.

Aberrantly spliced mRNAs of the 3-hydroxy-3-methylglutaryl coenzyme A lyase (HL) gene with a donor splice-site point mutation produce hereditary HL deficiency

A novel point mutation in the 3-hydroxy-3methyl-glutaryl coenzyme A lyase gene was found in a Turkish patient with homozygous 3-hydroxy-3-methylglutaric acidemia. Amplification by RT-PCR of the mRNA using a six different pairs of oligonucleotides produced no differences in four of the fragments amplified with respect to the control, but generated two fragments of different size. One was representative of a deletion of 126 bp and the other of an insertion of 78 bp. These abnormal mRNAs resulted from a G-->C transversion at the nucleotide +1 of an intron, which changed the invariant GT dinucleotide of the 5' donor splice site. This was associated with the occurrence of an alternative splicing, which led to the skipping of the whole exon of 126 bp, and also with the activation of one cryptic donor splice site in the same intron. These aberrant spliced mRNAs are predicted to encode two abnormal HMG-CoA lyase proteins: the first results in a protein with an internal deletion of 42 amino acids, whose enzyme activity is largely abolished, as the catalytic site was completely removed; the second contains 17 missense amino acids that precede a stop codon. Northern blot analysis showed that the overall content of these aberrantly spliced mRNAs in proband fibroblasts was the same as that found in control fibroblasts. However, hardly any transcript was observed corresponding to the inserted mutated mRNA when it was examined by a specific probe. To quantify the relative proportion of the two mRNAs, a quantitative RT-PCR (the DNA-mimic PCR reaction) was carried out. Results show that the proportion of the inserted mRNAs with respect to the deleted mRNA is only 1.2%. The father, mother, and two brothers of the proband were heterozygous in the G-->C mutation in the +1 nucleotide of the intron considered, while the two alleles of another brother were free of the mutation.

Monograph series on aging-related diseases: VIII. Non-insulin-dependent diabetes mellitus (NIDDM)

Diabetes mellitus is a chronic metabolic disease characterized by hyperglycemia and by disturbances of carbohydrate, fat and protein metabolism. Diabetes mellitus is associated with absolute or relative deficiency in the secretion and/or action of the hormone insulin.