Oestrogens as modulators of neuronal signalosomes and brain lipid homeostasis related to protection against neurodegeneration

Oestrogens trigger several pathways at the plasma membrane that exert beneficial actions against neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. Part of these actions takes place in lipid rafts, which are membrane domains with a singular protein and lipid composition. These microdomains also represent a preferential site for signalling protein complexes, or signalosomes. A plausible hypothesis is that the dynamic interaction of signalosomes with different extracellular ligands may be at the basis of neuronal maintenance against different neuropathologies. Oestrogen receptors are localised in neuronal lipid rafts, taking part of macromolecular complexes together with a voltage-dependent anion channel (VDAC), and other molecules. Oestradiol binding to its receptor at this level enhances neuroprotection against amyloid-β degeneration through the activation of different signal transduction pathways, including VDAC gating modulation. Moreover, part of the stability and functionality of signalling platforms lays on the distribution of lipid hallmarks in these microstructures, which modulate membrane physicochemical properties, thus favouring molecular interactions. Interestingly, recent findings indicate a potential role of oestrogens in the preservation of neuronal membrane physiology related to lipid homeostasis. Thus, oestrogens and docosahexaenoic acid may act synergistically to stabilise brain lipid structure by regulating neuronal lipid biosynthetic pathways, suggesting that part of the neuroprotective effects elicited by oestrogens occur through mechanisms aimed at preserving lipid homeostasis. Overall, oestrogen mechanisms of neuroprotection may occur not only by its interaction with neuronal protein targets through nongenomic and genomic mechanisms, but also through its participation in membrane architecture stabilisation via 'lipostatic' mechanisms.

Identification of a new HLA-C allele, HLA-C*08:75 in a Caucasian individual

HLA-C*08:75 differs from C*08:02:01 by a non-synonymous mutation at codon 229 (GAG to AAG) in exon 4.

Identification of a new HLA-C allele, HLA-C*08:76 in a Caucasian individual

HLA-C*08:76 differs from HLA-C*08:02:01 by one nonsynonymous nucleotide change at the codon 144 (CAG to AAG) in exon 3.

Soluble fatty acid synthase relates to bone biomarkers in prepubertal children

SUMMARY

Circulating soluble fatty acid synthase (FASN, a key enzyme in de novo biosynthesis of fatty acids, expressed in both adipocytes and osteoblasts) is clinically related to a less favorable bone profile in healthy prepubertal children. Soluble FASN may participate in the reciprocal regulation between fat and bone metabolism.

INTRODUCTION

Fatty acid synthase (FASN), a key enzyme in de novo biosynthesis of fatty acids, is expressed in adipocytes and osteoblasts. We hypothesized that FASN may participate in the crosstalk between fat and bone. To this aim, we studied the relation between circulating soluble FASN (an extracellular FASN that reflects previously intracellular enzymatic activity) and adipose tissue and bone biomarkers in prepubertal children.

METHODS

Circulating soluble FASN, total and high molecular weight (HMW) adiponectin, bone biomarkers [osteocalcin (OC), uncarboxylated osteocalcin (ucOC), C-terminal cross-linked telopeptide of type I collagen (CTX), bone-specific alkaline phosphatase (BSAP)], and a profile of energy metabolism [body fat, insulin resistance and secretion (HOMA), serum lipids] were assessed in 84 asymptomatic prepubertal children (44 girls, 40 boys, age 6.8 ± 0.1 year). Serum 25-OH Vitamin D (Vit D) was additionally measured.

RESULTS

Circulating soluble FASN increased with increasing HMW adiponectin (r = 0.29, p = 0.01) and decreasing serum Vit D (r = -0.21, p < 0.05), and was related to a less favorable bone profile, showing negative associations with bone-derived metabolic parameters [total OC (r = -0.33, p = 0.002) and ucOC (r = -0.37, p < 0.0001)] and a positive association with the CTX-to-BSAP ratio (r = 0.31, p < 0.01). These correlations were not explained by age, gender, body fat, insulin resistance or secretion or serum lipids; however, they were predominant in those subjects with Vit D levels below the population median.

CONCLUSIONS

Circulating soluble FASN relates to both adipose tissue and bone biomarkers in prepubertal children, with associations that are dependent on Vit D concentrations. These findings suggest that FASN may participate in the crosstalk between fat and bone metabolism.

Effects of oestradiol on brain lipid class and Fatty Acid composition: comparison between pregnant and ovariectomised oestradiol-treated rats

To determine the involvement of physiological doses of oestradiol on brain lipid composition, we have analysed the lipid class and fatty acid composition of phospholipids in the brain from pregnant and 17β-oestradiol-treated rats. Rats were randomly divided into three groups: ovariectomised control (OVX + VEH), ovariectomised oestradiol-treated (OVX + E(2) ) and pregnant (PREG) rats. Rats from the OVX + E(2) group were injected daily with different doses of 17β-oestradiol mimicking the plasma levels observed during pregnancy. Analyses of brain lipid class composition showed that physiological doses of oestradiol increased cholesterol levels of the OVX + E(2) group compared to the OVX + VEH group. It was also found that cholesterol levels in the PREG group were significantly lower than in the OVX + VEH and OVX + E(2) groups, indicating the involvement of gestational hormones other than oestradiol in the regulation of brain cholesterol during pregnancy. Brains from pregnant rats also exhibited reduced levels of plasmalogens and saturated fatty acids compared to the ovariectomised groups, especially in the second half of pregnancy. Interestingly, analyses of fatty acid composition of phospholipids revealed that physiological doses of oestradiol increased brain docosahexaenoic acid (DHA; 22:6 n-3) levels. Moreover, DHA levels in pregnant rats were similar to those observed in the OVX + E(2) group at all stages, suggesting that oestradiol is the main hormone in the regulation of brain DHA levels during pregnancy. Liver appears to be the major source for n-3 and n-6 long chain polyunsaturated fatty acids (LCPUFAs) DHA and arachidonic acid, which are released and transported to the maternal brain and the developing foetus under the influence of oestrogens. We also observed that the largest depots of n-3 and n-6 LCPUFA precursors (linolenic acid and linoleic acid, respectively) occur in adipose tissue triglycerides, which, in turn are significantly increased during pregnancy. Our observations are in accordance with an oestradiol-induced increased bioavailability of brain DHA in pregnant rats. We hypothesise that the reduction of maternal brain DHA observed at the end of pregnancy is a result of the very high demand DHA of foetal brain, which overcomes the maximal maternal (and likely foetal) capacity for de novo DHA synthesis in the liver and brain.

[Bean or blue rubber blue nevus syndrome. Presentation of 6 patients]

INTRODUCTION/AIMS

Bean or Blue Rubber Bleb Nevus Syndrome (BRBNS) is an uncommon disease characterized by multifocal venous malformations that predominantly affect the skin, soft tissues and gastrointestinal tract. Our objective is to familiarize the pediatric surgeon with this condition, promoting early diagnosis and seriated surgical treatment as therapeutic options. We have reviewed the diagnosis and treatment of 6 patients treated from 1993 to 2009.

MATERIAL AND METHODS

All the patients had a venous malformation (> 10 cm) that acted as a marker. After, characteristic skin lesions appeared as well as chronic anemia due to digestive bleeding associated to hypofibrinogenemia. Age of appearance of the anemic picture varied from 6 months to 7 years, it being more aggressive the earlier its appearance. The diagnosis of the disease was made by endoscopically. All the patients required transfusion with blood derivatives 5 to 25 times a year. Treatment was multidisciplinary: periodic transfusions in every case, endoscopic sclerosis in lesions that affect the colon or stomach and surgical treatment for lesions of the jejunum and ileum. In two of these patients, 23 and 46 lesions were excised, respectively. In the last year, the tendency has been to use enterotomy and fulguration with Argon.

RESULTS

The patients who have undergone excision of the digestive malformations have experienced a significant decrease in their transfusion needs. One female patient with miliary dissemination died.

CONCLUSIONS

BRBNS is a difficult to diagnose due to its low frequency. Treatment of gastrointestinal tract lesions is multidisciplinary, combining endoscopic and surgical techniques that decrease transfusions and improve the quality of life of the patients.

Telemedicine network physical connection design for remote areas. Case Baruta--El Hatillo

The telemedicine has increased mostly over recent years. Especially in developing countries where a high proportion of the population lives in rural areas or difficult to access. However it is successful implementation is closely connected with an appropriate design of the telecommunications network, part essential when deploying a network and the selection of appropriate communications technologies, realistic and sustainable according to the characteristics of the context in which it is deployed. This paper explain the situation of health centers in the municipalities Baruta and Hatillo in Venezuela, it proposes the design of a telemedicine network to allow interconnect the outpatient units with the referral hospital. Then it describes wireless technologies studied and finally it presents the entire design process of the network physical connection.

Interethnic differences in the accuracy of anthropometric indicators of obesity in screening for high risk of coronary heart disease

BACKGROUND

Cut points for defining obesity have been derived from mortality data among Whites from Europe and the United States and their accuracy to screen for high risk of coronary heart disease (CHD) in other ethnic groups has been questioned.

OBJECTIVE

To compare the accuracy and to define ethnic and gender-specific optimal cut points for body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) when they are used in screening for high risk of CHD in the Latin-American and the US populations.

METHODS

We estimated the accuracy and optimal cut points for BMI, WC and WHR to screen for CHD risk in Latin Americans (n=18 976), non-Hispanic Whites (Whites; n=8956), non-Hispanic Blacks (Blacks; n=5205) and Hispanics (n=5803). High risk of CHD was defined as a 10-year risk > or =20% (Framingham equation). The area under the receiver operator characteristic curve (AUC) and the misclassification-cost term were used to assess accuracy and to identify optimal cut points.

RESULTS

WHR had the highest AUC in all ethnic groups (from 0.75 to 0.82) and BMI had the lowest (from 0.50 to 0.59). Optimal cut point for BMI was similar across ethnic/gender groups (27 kg/m(2)). In women, cut points for WC (94 cm) and WHR (0.91) were consistent by ethnicity. In men, cut points for WC and WHR varied significantly with ethnicity: from 91 cm in Latin Americans to 102 cm in Whites, and from 0.94 in Latin Americans to 0.99 in Hispanics, respectively.

CONCLUSION

WHR is the most accurate anthropometric indicator to screen for high risk of CHD, whereas BMI is almost uninformative. The same BMI cut point should be used in all men and women. Unique cut points for WC and WHR should be used in all women, but ethnic-specific cut points seem warranted among men.

Early age at first sexual intercourse and early pregnancy are risk factors for cervical cancer in developing countries

Early age at first sexual intercourse (AFSI) has long been associated with an increased risk of invasive cervical carcinoma (ICC). Age at first pregnancy (AFP) and ICC have been investigated less, although AFSI and AFP are strongly interrelated in most developing countries. A pooled analysis of case–control studies on ICC from eight developing countries with 1864 cases and 1719 controls investigated the roles of AFSI, AFP, and ICC risk. Age at first sexual intercourse, AFP and age at first marriage (AFM) were highly interrelated and had similar ICC risk estimates. Compared with women with AFSI ⩾21 years, the odds ratio (OR) of ICC was 1.80 (95% CI: 1.50–2.39) among women with AFSI 17–20 years and 2.31 (95% CI: 1.85–2.87) for AFSI ⩽16 years (P-trend <0.001). No statistical interaction was detected between AFSI and any established risk factors for ICC. The ICC risk was 2.4-fold among those who reported AFSI and AFP at ⩽16 years compared with those with AFSI and AFP at ⩾21 years. These data confirm AFSI and AFB as risk factors for ICC in eight developing countries, but any independent effects of these two events could not be distinguished.

fMRI activity correlated with auditory hallucinations during performance of a working memory task: data from the FBIRN consortium study

INTRODUCTION

Auditory hallucinations are a hallmark symptom of schizophrenia. The neural basis of auditory hallucinations was examined using data from a working memory task. Data were acquired within a multisite consortium and this unique dataset provided the opportunity to analyze data from a large number of subjects who had been tested on the same procedures across sites. We hypothesized that regions involved in verbal working memory and language processing would show activity that was associated with levels of hallucinations during a condition where subjects were rehearsing the stimuli.

METHODS

Data from the Sternberg Item Recognition Paradigm, a working memory task, were acquired during functional magnetic resonance imaging procedures. The data were collected and preprocessed by the functional imaging biomedical informatics research network consortium. Schizophrenic subjects were split into nonhallucinating and hallucinating subgroups and activity during the probe condition (in which subjects rehearsed stimuli) was examined. Levels of activation from contrast images for the probe phase (collapsed over levels of memory load) of the working memory task were also correlated with levels of auditory hallucinations from the Scale for the Assessment of Positive Symptoms scores.

RESULTS

Patients with auditory hallucinations (relative to nonhallucinating subjects) showed decreased activity during the probe condition in verbal working memory/language processing regions, including the superior temporal and inferior parietal regions. These regions also showed associations between activity and levels of hallucinations in a correlation analysis.

DISCUSSION

The association between activation and hallucinations scores in the left hemisphere language/working memory regions replicates the findings of previous studies and provides converging evidence for the association between superior temporal abnormalities and auditory hallucinations.

Working memory and DLPFC inefficiency in schizophrenia: the FBIRN study

BACKGROUND

The Functional Imaging Biomedical Informatics Network is a consortium developing methods for multisite functional imaging studies. Both prefrontal hyper- or hypoactivity in chronic schizophrenia have been found in previous studies of working memory.

METHODS

In this functional magnetic resonance imaging (fMRI) study of working memory, 128 subjects with chronic schizophrenia and 128 age- and gender-matched controls were recruited from 10 universities around the United States. Subjects performed the Sternberg Item Recognition Paradigm1,2 with memory loads of 1, 3, or 5 items. A region of interest analysis examined the mean BOLD signal change in an atlas-based demarcation of the dorsolateral prefrontal cortex (DLPFC), in both groups, during both the encoding and retrieval phases of the experiment over the various memory loads.

RESULTS

Subjects with schizophrenia performed slightly but significantly worse than the healthy volunteers and showed a greater decrease in accuracy and increase in reaction time with increasing memory load. The mean BOLD signal in the DLPFC was significantly greater in the schizophrenic group than the healthy group, particularly in the intermediate load condition. A secondary analysis matched subjects for mean accuracy and found the same BOLD signal hyperresponse in schizophrenics.

CONCLUSIONS

The increase in BOLD signal change from minimal to moderate memory loads was greater in the schizophrenic subjects than in controls. This effect remained when age, gender, run, hemisphere, and performance were considered, consistent with inefficient DLPFC function during working memory. These findings from a large multisite sample support the concept not of hyper- or hypofrontality in schizophrenia, but rather DLPFC inefficiency that may be manifested in either direction depending on task demands. This redirects the focus of research from direction of difference to neural mechanisms of inefficiency.

Health and economic impact of HPV 16 and 18 vaccination and cervical cancer screening in India

Cervical cancer is a leading cause of cancer death among women in low-income countries, with approximately 25% of cases worldwide occurring in India. We estimated the potential health and economic impact of different cervical cancer prevention strategies. After empirically calibrating a cervical cancer model to country-specific epidemiologic data, we projected cancer incidence, life expectancy, and lifetime costs (I$2005), and calculated incremental cost-effectiveness ratios (I$/YLS) for the following strategies: pre-adolescent vaccination of girls before age 12, screening of women over age 30, and combined vaccination and screening. Screening differed by test (cytology, visual inspection, HPV DNA testing), number of clinical visits (1, 2 or 3), frequency (1 x , 2 x , 3 x per lifetime), and age range (35-45). Vaccine efficacy, coverage, and costs were varied in sensitivity analyses. Assuming 70% coverage, mean reduction in lifetime cancer risk was 44% (range, 28-57%) with HPV 16,18 vaccination alone, and 21-33% with screening three times per lifetime. Combining vaccination and screening three times per lifetime provided a mean reduction of 56% (vaccination plus 3-visit conventional cytology) to 63% (vaccination plus 2-visit HPV DNA testing). At a cost per vaccinated girl of I$10 (per dose cost of $2), pre-adolescent vaccination followed by screening three times per lifetime using either VIA or HPV DNA testing, would be considered cost-effective using the country's per capita gross domestic product (I$3452) as a threshold. In India, if high coverage of pre-adolescent girls with a low-cost HPV vaccine that provides long-term protection is achievable, vaccination followed by screening three times per lifetime is expected to reduce cancer deaths by half, and be cost-effective.

Clinical pharmacokinetics of ferric natural protein in iron-deficient females

Although iron therapy is very common, few studies have assessed iron absorption or iron kinetics in general, particularly with Fe(3+). This was the primary objective of this study, with assessment of tolerance as a secondary objective. Eight nonsmoking iron-deficient females without other associated pathologies, with an average age of 21.62 +/- 1.69 years, were studied. The diagnosis of iron deficiency was established by determination of sideraemia (28.7 +/- 13.5 microg/dl), iron binding capacity (380.5 +/- 70.2 microg/dl) and ferritin (5 +/- 1.4 microg/L) on the prestudy visit. The women remained in the Phase I Unit during days 0, 1, 2 and 3 of the study. A serum iron concentration curve was obtained daily from blood samples drawn at 0, 1, 2, 4, 6, 8 and 12 hours postdose. Therapy with ferric natural protein (ferrimannitol ovoalbumin) 40mg twice daily was started on day 1 of the study and continued for 30 days. The following parameters were evaluated: area under the curve (AUC(0-12h)), peak iron concentration (C(max)) and time to reach peak concentration (t(max)). Serum iron concentration-time curves were practically flat on day 0, but showed an increase following ferric therapy (Friedman, p < 0.05), confirming the usefulness of the postabsorption test and good absorption of ferric iron (Fe(3+)). The increase in AUC (314.65 +/- 67.9 to 1174.44 +/- 1071.8 microg/dl.h) and C(max) (49 +/- 24.4 to 146 +/- 101.9 microg/dl) from day 1 and the correlation between both parameters (r(2) > 0.85, p </= 0.008) supported the use of either parameter. The t(max) ranged from 4 to 6 hours. Ferric therapy was well tolerated by all patients. This study shows that ferric iron contained in this preparation is well absorbed and provides a satisfactory method for evaluation of iron absorption.

Efficacy of liposomal amphotericin B for secondary prophylaxis of visceral leishmaniasis in HIV-infected patients

BACKGROUND AND OBJECTIVES

Visceral leishmaniasis (VL) is characterized by frequent relapses in HIV-infected patients, even in those who receive secondary prophylaxis. The aim of our study was to evaluate the efficacy of liposomal amphotericin B (L-AMB) for secondary prophylaxis of VL in HIV-infected patients.

METHODS

From January 2001 to December 2005, 17 HIV patients, with at least one previous episode of VL who received L-AMB as secondary prophylaxis for VL, were included in the study. Efficacy was measured as the proportion of patients remaining free (non-relapse) of VL at different time points. Relapses were analysed as time-to-relapse distribution and were evaluated by survival analysis using the Kaplan-Meier method.

RESULTS

Twenty-one episodes of VL were diagnosed and nine relapsed. The median follow-up time was 14 (5-44) months. The probability of remaining free of relapse at 6 months was 89.7% (95% CI, 76.2-100); at 12 months, the probability was 79.1% (95% CI, 61-97.2) and at 24 and 36 months, the probability was 55.9% (95% CI, 30.5-81.3). In the non-relapsing group, patients had a significant increase in CD4 cell levels of 102 (10-174) and 126 (4-159) cells/mm(3) at 12 and 24 months, respectively (P = 0.037), whereas in the relapsing group, no significant increase was observed. Prophylaxis with L-AMB was well tolerated and only three patients had a mild impairment of renal function without requiring any change in treatment.

CONCLUSIONS

L-AMB is well tolerated and useful for secondary prophylaxis of VL.

Polypharmacy in elders with cancer: An analysis of the Ohio medicaid population

19550

Background: Polypharmacy in the elderly complicates therapy, increases cost of treatment and is a challenge to healthcare agencies. However, the impact of polypharmacy on the care of the older cancer patient has been poorly described. The objective of this study was to characterize the use of pharmacy drugs in the month preceding cancer diagnosis among Ohio Medicaid beneficiaries 65 years of age or older, and diagnosed with incident breast, prostate, or colorectal cancer during the study period 1997–2001. Methods: Medicaid beneficiaries were identified by linking data from the Ohio Cancer Incidence Surveillance System (OCISS) with Medicaid enrollment and claims files on a year-by-year basis. Because of potentially incomplete claims history, the study was limited to patients who were enrolled in Medicaid continuously in the year preceding initial cancer diagnosis. Additionally, those with spenddown or nursing home stay in that time frame were excluded from the analysis. Demographics, anatomic cancer site and stage were retrieved from the OCISS, and all non-pharmacy claims for services received in the year prior to cancer diagnosis were accounted for in deriving the Charlson comorbidity score. Results: The study population included 652 patients: 282 with incident breast cancer, 111 with prostate cancer, and 259 with colorectal cancer. The median age was 73, 74, and 75 years among breast, prostate, and colorectal cancer patients, respectively. Nearly 45% were prescribed at least one type of medication in the month preceding cancer diagnosis. Of those with any prescription in that time period, nearly 49% were prescribed 5 or more types of medications. The most commonly prescribed types of medication were narcotic analgesics, diuretics and potassium replacement, anti- hypertensive agents, laxatives, antianxiety drugs, and antidpressants. No significant variations in the use of medications were observed across the different subgroups of the study population. Conclusions: Polpypharmacy (5 or more types of medication) was present in more than 22% of patients in this study population. The effects of polpypharmacy above and beyond that of comorbidities, disability, and other geriatric syndromes, relative to cancer-related outcomes should be determined.

No significant financial relationships to disclose.

[Complex lymphatic malformations: diagnostic and therapeutical implications]

BACKGROUND

Complex lymphatic malformations (CLM) consist of disturbances of lymphatic system development, most often with a genetic origin and with mixed vascular system involvement: lymphatic, venous and capillary. They affect a large corporal area or are associated to other syndromes or systemic diseases.

METHODS

We reviewed 21 patients with CLM treated in our hospital during the last 15 years. We used D2-40 monoclonal antibody (by immunohistochemistry) as lymphatic marker to evaluate the level of lymphatic involvement. Furthermore we analysed surgical implications in this group of patients.

RESULTS

Twelve children had only lymphatic involvement and nine mixed lymphatic-capillary or lymphatic-venous one. Two died of: respiratory insufficiency (in the neonatal period) and refractory hypoproteinemia (at 8 years of age). The skin was affected between 10 and 35% of total body surface. Three patients suffered from visceral involvement (lungs and mediastinum) and eighteen musculoskeletal. Severe deformity (20), lymphorhagia (15), repeated lymphangitis and chronic pain (5) were the most common symptoms reported. The immunoreaction intensity with monoclonal antibody D2-40 was related to the severity of the local and systemic involvement as well as to the presence of associated malformations. Fifteen cases underwent sequential surgical treatment, seven were treated with sclerotherapy (OK-432) and four with CO2 laser vaporization. Residual lymphorhagia in patients with total extirpation of the lymphatic malformation stopped after repeated evacuator punctures and healing took place.

CONCLUSIONS

(1) D2-40 monoclonal antibody is a marker of bad prognosis in CLM. (2) The complete excision of the lymphatic malformation lead to healing and the associated lymphorragia should not be considered as a recurrence, which will stop with evacuator punctures in all cases. (3) A multidisciplinary team approach is essential for the proper care of CLM in order to minimize postoperative sequelae and late complications.