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UNLABELLED: Hepcidin, an antimicrobial peptide which synthesis is regulated by iron status and inflammation, plays an important role in iron homeostasis in hemodialysed (HD) patients. It is measured by measuring serum prohepcidin. OBJECTIVE: To determine serum prohepcidin levels and their relationship with serum ferritin, C reactive protein (CRP), and albumin in HD patients treated or not with recombinant erythropoietin (EPO) that attended the Health Centre of the Carabobo State in Venezuela. METHODOLOGY: This is a descriptive, correlational, and field investigation with a sample comprised by 71 HD patients of whom 57 were treated with EPO. Serum prohepcidin, ferritin, haemoglobin, hematocrit, CRP, and albumin were determined. Anaemia (haemoglobin < 10 g/dL) and iron deficiency (ferritin < 100 ng/mL) were defined according to the criteria recommended by the K/DOQUI group. Reference values: Albumin 3.5-4.8 g/dL, and for acute inflammatory conditions (CRP > 10 mg/L.). RESULTS: The mean value for prohepcidin was 397.5 ng/mL. A high percentage of anaemia was observed (87.3%) and 22.5% of the patients had low levels of serum ferritin. There were no statistically significant differences for ferritin, albumin, CRP, or prohepcidin, between patients with and without EPO therapy. Only the CRP value was significantly correlated (rho = 0.276; p = 0.020) with prohepcidin. CONCLUSION: HD patients present high levels of prohepcidin, and this may be due to the common ongoing inflammatory process in these patients and not to the iron status measured through serum ferritin levels.

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Glucagonoma is an uncommon disease, a neuroendocrine tumour that develops from glucagon-producing pancreatic cells. They are usually slow-growing, but generally advanced at diagnosis, and metastatic disease is virtually incurable. Liver is the most common site of metastatic disease. We present the case of a 48-year-old man with a glucagonoma being diagnosed from a pulmonary mass. This case had no liver affection in the whole evolution of the disease, and showed a particularly aggressive course, with very little response to all therapies administered, and a survival from diagnosis of just 16 months.

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INTRODUCTION: Asthenia is the most prevalent symptom in oncological patients but it is underestimated by the majority of healthcare professionals. The aim of the present study is to estimate the prevalence of tumour-related asthenia in the Spanish population, while defining the associated factors. METHODS: An epidemiological, multicentre, cross-sectional study was conducted in oncology services from Spain, including 712 cancer patients (58.4+/-13.5 years). RESULTS: 42.5% patients showed asthenia. This prevalence appeared to be tumour-related (p<0.05) and increased among patients with a more advanced stage of disease or with a worsening of performance status (p<0.001). The prevalence of asthenia increased in the presence of the following factors: chemotherapy (in the past: 52.1% vs. 31.0%; at the time of the study: 46.1% vs. 38.2%), symptomatic treatment (in the past: 60.4% vs. 39.8%; at the time of the study: 61.3% vs. 38.6%), present interferon treatment (100%), anaemia (59.7% vs. 31.3%), dehydration/waterelectrolyte imbalance (58.3% vs. 41.6%), respiratory failure (61.4% vs. 39.7%), liver disease (59.5% vs. 41.3%), malnutrition (76.1% vs. 38.7%), pain (57.7% vs. 27.0%), anxiety (56.1% vs. 38.6%), depression (57.9% vs. 40.0%) and sleep disturbances (51.1% vs. 39.4%). A multivariate logistic regression showed that a model including performance status, patient circumstance, chemotherapy, anaemia, pain and anxiety correctly diagnosed asthenia in 70.9% of cases. CONCLUSIONS: The physiopathology of tumour-related asthenia remains relatively unknown, despite its high prevalence and considerable quality of life impact. Determining factors related to asthenia in clinical practice can favour the use of concrete treatments and improve the conditions of cancer patients.

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INTRODUCTION: Despite the high prevalence of asthenia in cancer patients, around 50-75%, and its impact on quality of life, it continues to be a difficult symptom to assess and manage. This study defines the extent of perception and diagnosis of asthenia associated with cancer among Spanish oncologists. METHODS: A descriptive, observational study conducted in Spain based on a five-part structured questionnaire available to participants through a private website. RESULTS: The 100 oncologists surveyed, most in the public healthcare setting, diagnose asthenia in 58-70% of cases. They consider old age (56.5%) and advanced-stage disease (94.2%) as factors associated with the occurrence of asthenia, which is also common in, particularly, tumours, such as pancreatic cancer (30.4%), and some therapies, notably chemotherapy alone (67%) or combined with radiotherapy (96%). Despite its adequate detection, physicians rarely ask their patients about asthenia, use instruments for its evaluation or assess its impact on quality of life. Likewise, only 40% of all patients are treated, although therapeutic intervention, a multidisciplinary approach combining drug and non-drug treatments and managing a variety of causative factors, can be considered adequate. Finally, 91.5% of those surveyed do not have action guidelines for asthenia in their hospitals. CONCLUSIONS: Even when asthenia is widely diagnosed in cancer patients in Spain, there is a laxity in its assessment and treatment. Increased awareness among healthcare professionals of its impact and relevance is therefore required, as well as adequate protocols for its systematic detection and management within the routine assessment and treatment of cancer patients.

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Signalling pathways that emerge from EGFR activation are critical in colon cancer (CC) biology. Its targeting with specific drugs has opened a new window in the treatment of this disease. In this regard, monoclonal antibodies (mAb) have evidenced a high degree of efficiency opposed to the uselessness of tyrosine-kinase inhibitors. Cetuximab is the mAb that has evidenced most activity in CC. After its initial approval as an irinotecan-resistance reversal agent, cetuximab has demonstrated its efficiency from the first line to heavily pretreated patients. In the first line, its addition may increase response rate to chemotherapy, improving liver metastases resection rate. Another promising approach has been suggested from combination schedules with bevacizumab. Panitumumab has been recently approved for CC. Although there is limited clinical experience, the latest data have confirmed its activity in heavily pretreated patients resulting in a clinical benefit vs. best support care. In spite of the clinical benefits, adverse events and the high sanitary cost derived from these drugs force the selection of patients with the highest probability of benefit. At the moment, when EGFR expression evidenced by immunohistochemistry has no value, skin toxicity and, fundamentally, K-Ras mutations may hint at critical information for confirmatory prospective studies.

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Although rare, cardiotoxicity is a significant complication of cancer treatment. The incidence and severity of cardiovascular side effects are dependent on the type of drugs used, dose and schedule employed, and age of patients, as well as the presence of coexisting cardiac diseases and previous mediastinal irradiation. Classically, anthracyclines are among one of the most active agents in oncology, but their use is often hampered by their cumulative dose-limiting cardiotoxicity. In the past decade, combination therapy with new drugs such as taxanes or anti- EGFR, and Her-2 therapy as a single agent have also resulted in unexpected cardiotoxicity. Cardiac damage can be secondary to an alteration of cardiac rhythm, changes in blood pressure and ischaemia, and can also alter the ability of the heart to contract and/or relax. The clinical spectrum of these toxicities can range from subclinical abnormalities to being catastrophic, life-threatening and sometimes fatal. Knowledge of this toxicity can aid clinicians to choose the optimal and least toxic regimen suitable for an individual patient. In this work we present an exhaustive review of the cardiovascular side effects associated to new anticancer drugs, from new formulations of anthracyclines to tyrosine kinase inhibitors and monoclonal antibodies.

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Cerebral metastases from colorectal cancer occur in 8% of cases. Diagnosis is usually made when primary disease and widespread metastases are already known. However, the detection of brain metastases as the first sign of colorectal carcinoma without any liver and/or lung involvement is extremely rare. Central nervous system metastases are more commonly seen in rectal cancer and often occur concurrently with lung metastasis. We report a case of a patient with brain metastases as the first clinical manifestation of an adenocarcinoma of caecum without any other organ involvement.

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Colorectal cancer (CRC) is the second leading cause of cancer death in Western countries. CRC treatment is based on the employment of three chemotherapeutic drugs, including 5-fluorouracil, oxaliplatin and irinotecan, and the use of recently incorporated targeted agents directed to vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR). The approval of these biologicals and of others to come holds great promise for the improvement of patient outcome. The molecular bases for this lethal disease have been extensively investigated, laying the foundations for a rational and customised treatment approach, expanding the therapeutic index of current drugs and easing the incorporation of new molecules. Individual markers have been mainly investigated based on drug targets and metabolism. Also, the increasing availability of highthroughput technologies has prompted the opportunity for blind studies capable of screening new markers and of identifying the specific oncogenic pathways responsible for drug resistance in a given patient. An updated review of the field is presented in this article.

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Lung cancer is a frequent cause of cancer-related deaths in the world. There is no valid screening process and this limits its detection to the late stages, with consequently high mortality rates. Volatile organic compounds (VOC) are chemical compounds (mainly the products of cell catabolism) found as gases in the human breath. Different methods have been developed to analyse VOCs and to compare them in healthy subjects and lung cancer patients. In this review, we summarise the different techniques used to analyse VOC. Many reports have been published with promising results similar to those achieved with accepted screening methods such as mammography. These methods show good perspectives on lung cancer screening.

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Oxycodone is a semi-synthetic opioid with an agonist activity on mu, kappa and delta receptors. Equivalence with regard to morphine is 1:2. Its effect commences one hour after administration and lasts for 12 h in the controlled-release formulation. Plasma halflife is 3-5 h (half that of morphine) and stable plasma levels are reached within 24 h (2-7 days for morphine). Oral bioavailability ranges from 60 to 87%, and plasma protein binding is 45%. Most of the drug is metabolised in the liver, while the rest is excreted by the kidney along with its metabolites. The two main metabolites are oxymorphone--which is also a very potent analgesic--and noroxycodone, a weak analgesic. Oxycodone metabolism is more predictable than that of morphine, and therefore titration is easier. Oxycodone has the same mechanism of action as other opioids: binding to a receptor, inhibition of adenylyl-cyclase and hyperpolarisation of neurons, and decreased excitability. These mechanisms also play a part in the onset of dependence and tolerance. The clinical efficacy of oxycodone is similar to that of morphine, with a ratio of 1/1.5-2 for the treatment of cancer pain. Long-term administration may be associated with less toxicity in comparison with morphine. In the future, both opioids could be used simultaneously at low doses to reduce toxicity. It does not appear that there are any differences between immediate and slow-release oxycodone, except their half-life is 3-4 h, and 12 h, respectively. In Spain, controlled-release oxycodone (OxyContin) is marketed as 10-, 20-, 40- or 80-mg tablets for b.i.d. administration. Tablets must be taken whole and must not be broken, chewed or crushed. There is no food interference. The initial dose is 10 mg b.i.d. for new treatments and no dose reduction is needed in the elderly or in cases of moderate hepatic or renal failure. Immediate-release oxycodone (OxyNorm) is also available in capsules and oral solution. Side effects are those common to opioids: mainly nausea, constipation and drowsiness. Vomiting, pruritus and dizziness are less common. The intensity of these side effects tends to decrease over the course of time. Oxycodone causes somewhat less nausea, hallucinations and pruritus than morphine.

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Los cambios anatomo-fisiológicos propios del envejecimiento hacen de los adultos mayores un grupo vulnerable a los estados de malnutrición y deficiencias específicas de nutrientes como la vitamina B12 y el folato. El objetivo de este estudio fue establecer la relación existente entre la vitamina B12, folato, homocisteína y el consumo y adecuación de estos nutrientes. Se evaluaron 55 adultos mayores de 60 años de edad, de ambos sexos, no institucionalizados, a quienes se les determinó homocisteína sérica por inmunoensayo de polarización de fluorescencia, vitamina B12 y folato sérico por radioensayo (RIA); consumo de nutrientes según recordatorio de 24 h y frecuencia de consumo de alimentos y estado nutricional antropométrico según Indice de Masa Corporal (IMC). Se encontraron niveles séricos de vitamina B12 y folato dentro de los valores de referencia (423,3± 227,6 pmol/l y 6,4 ± 4,5 mg/ml); sin embargo, 17,5% se encontraban deficitarios de B12 y 12% de ácido fólico, la homocisteína sérica estuvo por encima de los valores de referencia (15,8±4,4 mmol/l). Del grupo de estudio, 47,5% presentaban hiperhomocisteinemia (>15mmol/L), siendo significativamente más alta para el sexo masculino (p: 0,01). El consumo de nutrientes fue inadecuado por déficit. Según IMC, 11,8% de los adultos mayores se encontraban en déficit nutricional, 29,4% con sobrepeso y 20,6% en obesidad. Se observó una correlación inversa y negativa entre homcisteína y folato sérico. Todo esto sugiere la presencia de una deficiencia bioquímica de B12 y folato, que se traduce en la homocisteína elevada, lo que constituye un factor de riesgo cardiovascular en este grupo de adultos mayores.

Serum homocysteine, folate and vitamin B12 in Venezuelan elderly. The anatomical and physiological changes of aging make elderly people a vulnerable group to malnutrition and specific deficiencies of nutrients such as vitamin B12 and folate. This study was aimed to establish relationships among serum vitamin B12, folate, homocysteine concentrations and dietary intake and adequacy. Fifty five male and female elderly (60 and more years), free-living, were assessed. Measurements were: serum vitamin B12 and folate by radioimmunoanalysis (RIA), homocysteine by polarized fluorescence immunoassay, nutrient intake by three 24 hours recalls and food frequency questionnaire. Nutritional status was determined by Body Mass Index (BMI). Serum vitamin B12 and folate were at normal range (423,3±227,6 pmol/l and 6,4 ± 4,5 mg/ml), but 17,5% of elderly had B12 deficiency and 12% had folate deficiency. Serum homocysteine was higher than reference values (15,8±4,4 mmol/l), but 47,5% showed concentrations above 15mmol/L, male population showed higher mean value (p: 0,01). Nutrient intake was inadequate by deficiency. BMI indicated 11,8% of undernutrition, 29,4% of overweight and 20,6% of obesity A negative and inverse correlation between homocysteine and serum folate was found. Results suggest a biochemical deficiency of B12 and folate that is expressed as elevated homocysteine levels. These finding represent a high cardiovascular risk factor for this elderly group.

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La infección con Helicobacter pylori (Hp) está altamente diseminada a nivel mundial y es considerada una de las causas principales de gastritis crónica, úlceras pépticas y duodenales y cáncer gástrico. Trabajos recientes han mostrado que esta puede tener implicaciones nutricionales, principalmente sobre el estado de hierro y otros micronutrientes. El objetivo fue evaluar la prevalencia de infección con Hp y el patrón de infección según edad, sexo, estado nutricional y condiciones socioeconómicas, en niños que asistían a Unidad Educativa "Valentín Espinal" de Valencia. Se evaluaron 170 niños entre 3 y 14 años de edad, de ambos géneros. Se determinó: Infección por Hp (test de aliento con urea-C13), edad, estado nutricional según IMC y Talla-Edad, hemoglobina (cianometahemoglobina), ferritina sérica (ELISA), estrato socioeconómico (Graffar-Méndez-Castellano), condición de vivienda, número de personas y familias que viven en el hogar y calidad de los servicios. El 78,8 por ciento de los niños estaban infectados con Hp, no encontrándose correlación significativa con el género pero si con la edad; 25,9 por ciento presentaron déficit nutricional y 46,5 por ciento talla baja, El 98,1 por ciento de las familias se encontraban en situación de pobreza (estratos IV y V) y 98 por ciento de las viviendas presentaban deficiencias sanitarias; En promedio vivían 6,0±2,4 personas en el hogar (rango: 2 a 15) y 3,2 personas compartían un mismo dormitorio. Se encontró que la probabilidad de infección era mayor en aquellos niños que presentaban déficit de talla y que el estrato socioeconómico, el nivel de instrucción materno, las precarias condiciones de alojamiento y el hacinamiento se asociaban significativamente a la infección. La deprivación socioeconómica en la niñez esta asociada con una alta colonización del Hp, la edad, el hacinamiento y un bajo nivel de instrucción de la madre pueden aumentar el riesgo a esta infección

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BACKGROUND: Pain and suffering are not synonymous terms. The concept of suffering is wider than just physical pain. People can suffer for multiple causes, pain among them, but it is not the only reason since <>. If our main objective is the achievement of the well-being and the relief of pain, it will be necessary, according to Lazarus, Folkman, Chapman, Gravin, Bayés and Labrador, to reduce or eliminate the physical (cancer, pain and so on) and psychosocial harm (loneliness, culpability, etc.) perceived like a threat and to increase the perception of control about this situation. AIMS: The main objectives of our work were: First: to evaluate the efficacy of a tool that allows the identification of the symptoms perceived by the patient as a threat in order to reduce or suppress them and empower their resources at the same time; and secondly to evaluate the incidence of pain in the suffering. MATERIALS AND METHODS: Our tool includes the following groups of variables: subjective perception of the time course, emotional aspects, concerns and confrontation strategies, perception of adaptation and sense of life, perceived support and pain. This tool has been tested in 73 oncologic patients, 31 men and 42 women, mean aged 55, 41 (SD = 14, 54) visited at the Medical Oncology Service of La Paz Hospital. RESULTS: Mainly, people who refers great suffering are those with more pain (p < 0.05); while patients with less suffering and higher well-being are those that use strategies to face their situation (p < 0.05). Our tool reduces perceived threats and that reflects the need for a good control of pain and at the same time to empower the resources to relieve the suffering as much as possible. CONCLUSION: The referred tool seems to be effective in order to easy the intervention to relieve the suffering.

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Helicobacter pylori infection (Hp) is widely spread around the world, and it is considered one of the main causes of chronic gastritis, peptic and duodenal ulcers, and gastric cancer. Recent research has shown that it can be associated with nutritional disorders, mainly with iron and other micronutrient deficiencies. The objective of this study was to assess the prevalence of Hp infection, and infection pattern according to age, sex, nutritional status, and socioeconomic conditions in children who attended the Unidad Educativa "Valentin Espinal" in the city of Valencia. 170 children, between 3 and 14 years of age were studied to assess Hpylori infection (13C-urea breath test), age, nutritional status according to BMI and Height for age, hemoglobin (cianometahemoglobin), serum ferritin (ELISA), socioeconomic status (Graffar-Méndez-Castellano), housing conditions, number of families and of people cohabitating in the same household, and quality of services. 78.8% of the children were infected with Hp, witch was significantly correlated with age but not gender. 25.9% of the sample had undernutrition, and 46.5% were stunted. 98.1% of the families lived in poverty, and 98% of the households showed sanitary deficiencies. A mean of 6.0 +/- 2.4 persons lived in each household (range: 2-15), and an average of 3.2 person shared bedrooms. The odds of being infected were higher in those children who were stunted. Also, socioeconomic status, mother's education level, and poor hosing conditions were significantly associated to being infected. Hpylori is highly prevalent among socially and economically deprived children, and age, overcrowding, and a low education level of the mother increases the risk of being infected.

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INTRODUCTION: A number of findings suggest that cyclooxygenase-2 (COX-2) is overexpressed in breast tumours. However, there is a lack of consensus in the literature regarding the pattern of expression of this protein in invasive breast ductal carcinoma and in the adjacent non-tumour ductal epithelium. This study compares the expression of COX-2 mRNA and protein in breast ductal carcinoma relative to non-tumour breast tissue. MATERIAL AND METHODS: We analysed the expression of COX-2 mRNA by quantitative PCR, and COX-2 protein by immunohistochemistry in invasive ductal carcinoma as well as in non-tumour adjacent ductal epithelium from 34 breast biopsies diagnosed as being invasive ductal carcinoma. As control, we analysed expression of COX-2 protein by immunohistochemistry in surgically-resected benign breast lesions. RESULTS: Our results show that COX-2 mRNA and protein are overexpressed in non-tumour ductal epithelium compared with invasive ductal carcinoma. However, the pattern of the protein expression is different in tumour and non-tumour tissue: COX-2 protein is expressed predominantly in the membrane of the non-tumour ductal epithelium (including in benign breast lesions) while, in invasive ductal carcinoma cells, it is localised in the cytoplasm. CONCLUSIONS: The non-tumour ductal epithelium adjacent to invasive ductal carcinoma shows a higher COX-2 expression than does the invasive ductal carcinoma. However, the different localisation of the immunohistochemically-detected protein suggests a possible post-translational regulation of the protein.

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Pregnancy in adolescence increases nutritional risk, due to higher demand of nutrients for maternal and fetal growth. This study was aimed to evaluate folate, vitamin B12 and iron status of pregnant adolescents at first trimester of pregnancy. A cross sectional, descriptive study was performed in 122 pregnant adolescents from Valencia, Carabobo state, 1997. Serum and erythrocyte folate and serum vitamin B12 was determined by radioassay; serum ferritin by enzimoimmunoassay; hemoglobin were performed by semi-automated method. Statistical analysis included standard deviation and frequencies. For serum folate 1.7 per cent was found in negative balance and 19.0 per cent at marginal status. For erythrocyte folate, 5.8 per cent was deficient and 1.7 per cent marginal. For serum vitamin B12, 8.3 per cent was deficient and 13.2 per cent marginal. Iron deficiency was found in 19.0 per cent of the adolescents. Prevalence of anemia was of 13.1 per cent, being iron deficiency the main cause. There was high nutritional risk regarding iron status, although iron intakes exceeded the recommendations, but only a small proportion was bioavailable. Prevalence of anemia was lower than reported by other studies and iron deficiency was higher than folic acid and vitamin B12 deficiencies. Pregnant adolescents are at a high biological and nutritional risk.

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Kinetic conditions were established for the depolymerization of cassava starch for the production of maltodextrins and glucose syrups. Thin-layer chromatography and high-performance liquid chromatography analyses corroborated that the proper H3PO4 strength and thermopressurization range (e.g., 142-170 degrees C; 2.8-6.8 atm) can be successfully explored for such hydrolytic purposes of native starch granules. Because phosphoric acid can be advantageously maintained in the hydrolysate and generates, after controlled neutralization with ammonia, the strategic nutrient triplet for industrial fermentations (C, P, N), this pretreatment strategy can be easily recognized as a recommended technology for hydrolysis and upgrading of starch and other plant polysaccharides. Compared to the classic catalysts, the mandatory desalting step (chloride removal by expensive anion-exchange resin or sulfate precipitation as the calcium-insoluble salt) can be avoided. Furthermore, properly diluted phosphoric acid is well known as an allowable additive in several popular soft drinks such as colas since its acidic feeling in the mouth is compatible and synergistic with both natural and artificial sweeteners. Glycosyrups from phosphorolyzed cassava starch have also been upgraded to high-value single-cell protein such as the pigmented yeast biomass of Xanthophyllomyces dendrorhous (Phaffia rhodozyma), whose astaxanthin (diketo-dihydroxy-beta-carotene) content may reach 0.5-1.0 mg/g of dry yeast cell. This can be used as an ideal complement for animal feeding as well as a natural staining for both fish farming (meat) and poultry (eggs).

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OBJECTIVES: For acutely ill children living in less than optimal environments, mothers and pediatricians may have a heightened perception of illness severity, a lower specificity of clinical judgments, and a tendency to over-utilize resources. We examined the mother-child interaction in order to understand the relation of less optimal environments to clinical judgment and resource use. STUDY DESIGN: At the 2-week and 6-, 15-, and 24-month well child visits of 316 children, the mother-well child interaction was assessed by using the Biringen's Emotional Availability Scales (EAS). Data were gathered regarding maternal depression and sense of competence, infant temperament, maternal social support, life events, the home environment, and demographics. At ill visits, the mother-ill child interaction was assessed by using the EAS, and mothers and pediatricians independently assessed illness severity using the Acute Illness Observation Scales. Resource use during the illness was evaluated. RESULTS: One thousand nine hundred eight-three acute illnesses were assessed. A less optimal mother-child interaction was significantly (P <.05 for all comparisons) associated with poorer reliability of mothers' judgments, lower specificity of mothers' judgments (71% vs 85%) and pediatricians' judgments (92% vs 97%), and greater use of resources (eg, for hospitalizations, 2.6% of visits vs 0.7%). Adverse maternal, infant, and demographic characteristics were associated with a less optimal mother-well child (r = 0.68) and mother-ill child (r = 0.80) interaction, a heightened perception of illness severity, and greater resource use. CONCLUSION: Less optimal environments adversely affect the mother-child interaction; a poor mother-child interaction is correlated with low specificity of clinical judgment and over-utilization of resources.

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One hundred and seventy four human subjects were studied to find out the interaction of vitamin A or beta-carotene with the inhibitors of iron absorption, from a basal breakfast containing bread from either 100 g of precooked corn flour or 100 g of white wheat flour, 50 g of cheese and 10 g of margarine. Bread was labeled with either 55Fe or 59Fe. This bread was made from commercially flours fortified with iron as ferrous fumarate and vitamins. It was noticed that the percentage of iron absorption from the breakfast prepared with precooked corn flour given alone and with different concentrations of coffee was practically the same, while the iron absorption from the breakfast prepared from wheat flour decreased from 6% when the breakfast was given alone, to less than 2% when it was given with different concentrations of coffee. The only ingredient present in precooked corn flour and not in wheat flour was vitamin A. This difference encouraged the authors to perform further experiments using precooked corn and wheat flours fortified only with ferrous fumarate. These studies demonstrated that vitamin A inhibits the effect of the polyphenol and partially inhibits the effect phytate on iron absorption. HPLC and spectrophotometric studies demonstrated an interaction between vitamin A and iron. Other experiments, which included 100 volunteers, were performed to test the effect of vitamin A and beta-carotene on iron absorption from corn, wheat and rice. The presence of vitamin A increased iron absorption up to 3 times for rice, 2.4 times for wheat and 1.8 times for corn. beta-carotene increased absorption almost 3 times for the three cereals tested, showing that both compounds were capable of preventing the inhibitory effect of phytates on iron absorption. This information suggest that vitamin A and beta-carotene form a complex with iron keeping it soluble in the intestinal lumen and preventing the inhibitory effect of phytates and polyphenols on iron absorption.

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