A hybrid achromatic metalens.

Metalenses, ultra-thin optical elements that focus light using subwavelength structures, have been the subject of a number of recent investigations. Compared to their refractive counterparts, metalenses offer reduced size and weight, and new functionality such as polarization control. However, metalenses that correct chromatic aberration also suffer from markedly reduced focusing efficiency. Here we introduce a Hybrid Achromatic Metalens (HAML) that overcomes this trade-off and offers improved focusing efficiency over a broad wavelength range from 1000-1800 nm. HAMLs can be designed by combining recursive ray-tracing and simulated phase libraries rather than computationally intensive global search algorithms. Moreover, HAMLs can be fabricated in low-refractive index materials using multi-photon lithography for customization or using molding for mass production. HAMLs demonstrated diffraction limited performance for numerical apertures of 0.27, 0.11, and 0.06, with average focusing efficiencies greater than 60% and maximum efficiencies up to 80%. A more complex design, the air-spaced HAML, introduces a gap between elements to enable even larger diameters and numerical apertures.

[The use of ondansetron in acute gastroenteritis. Its impact in a pediatric emergency department]. / L'impiego dell'ondansentron nella gastroenterite acuta e la sua efficacia in un pronto soccorso pediatrico.

BACKGROUND: Ondansentron is in consideration in literature for its use in vomiting secondary to acute gastroenteritis in children. OBJECTIVE: To evaluate its usefulness in children with acute gastroenteritis referred to a paediatric emergency department. METHODS: A retrospective study considered 967 children treated with ondansetron (0,06 mg/kg IM) plus oral rehydration, with a control group of 286 children who received only oral rehydration. RESULTS: The time spent into the short-stay observation unit and the total emergency department stay were significantly reduced in children receiving ondansentron. No adverse reactions to the drug were recorded.

[The use of ondansetron in acute gastroenteritis. Its impact in a pediatric emergency department]. / L'impiego dell'ondansentron nella gastroenterite acuta e la sua efficacia in un pronto soccorso pediatrico.

BACKGROUND: Ondansentron is in consideration in literature for its use in vomiting secondary to acute gastroenteritis in children. OBJECTIVE: To evaluate its usefulness in children with acute gastroenteritis referred to a paediatric emergency department. METHODS: A retrospective study considered 967 children treated with ondansetron (0,06 mg/kg IM) plus oral rehydration, with a control group of 286 children who received only oral rehydration. RESULTS: The time spent into the short-stay observation unit and the total emergency department stay were significantly reduced in children receiving ondansentron. No adverse reactions to the drug were recorded.

Autoimmune liver diseases in a paediatric population with coeliac disease - a 10-year single-centre experience.

BACKGROUND: Coeliac disease (CD) can be associated with liver disease. Gluten-free diet (GFD) normalizes cryptogenic forms, but most likely not autoimmune hepatitis (AIH). For this condition, immunosuppressants represent the treatment. However, when these are stopped, AIH generally relapses. AIM: To determine in CD children liver test abnormality frequency, the effect of GFD alone, or plus prolonged immunosuppressants on AIH course. METHODS: Coeliac disease patients with abnormal transaminases were selected; if transaminases <5 x UNL (upper normal limits), GFD alone was administered; if >5 x UNL, liver examinations and biopsy were performed. In AIH, immunosuppressants were administered (5 years). Treatment was stopped only if patients remained in remission during the entire maintenance period and normalized liver histology. RESULTS: A total of 140 out of 350 CD children had hypertransaminaemia: 133 cryptogenic disease, 7 AIH. GFD normalized only cryptogenic hepatitis. During treatment, all AIH persistently normalized clinical and biochemical parameters; after withdrawal, six patients maintained a sustained remission (follow-up range: 12-63 months), while one relapsed. CONCLUSIONS: In CD children with AIH, only GFD plus immunosuppressants determines a high remission rate. When clinical remission is reached, a prolonged immunosuppressive regimen induces a high sustained remission rate after treatment withdrawal, indicating that this regimen may prevent early relapse.

Inflammatory bowel disease in children and adolescents in Italy: data from the pediatric national IBD register (1996-2003).

BACKGROUND: The purpose was to assess in Italy the clinical features at diagnosis of inflammatory bowel disease (IBD) in children. METHODS: In 1996 an IBD register of disease onset was established on a national scale. RESULTS: Up to the end of 2003, 1576 cases of pediatric IBD were recorded: 810 (52%) ulcerative colitis (UC), 635 (40%) Crohn's disease (CD), and 131 (8%) indeterminate colitis (IC). In the period 1996-2003 an increase of IBD incidence from 0.89 to 1.39/10(5) inhabitants aged <18 years was observed. IBD was more frequent among children aged between 6 and 12 years (57%) but 20% of patients had onset of the disease under 6 years of age; 28 patients were <1 year of age. Overall, 11% had 1 or more family members with IBD. The mean interval between onset of symptoms and diagnosis was higher in CD (10.1 months) and IC (9 months) versus UC (5.8 months). Extended colitis was the most frequent form in UC and ileocolic involvement the most frequent in CD. Upper intestinal tract involvement was present in 11% of CD patients. IC locations were similar to those of UC. Bloody diarrhea and abdominal pain were the most frequent symptoms in UC and IC, and abdominal pain and diarrhea in CD. Extraintestinal symptoms were more frequent in CD than in UC. CONCLUSIONS: The IBD incidence in children and adolescents in Italy shows an increasing trend for all 3 pathologies. UC diagnoses exceeded CD.

Rational approach to the treatment for heterozygous familial hypercholesterolemia in childhood and adolescence: a review.

Atherosclerosis represents a disease that begins in childhood and in which LDL cholesterol plays a pivotal role for the development of the pathology. Children and adolescents with high cholesterol levels are more likely than their peers to present cholesterol elevation as adults. The identification of genetic dyslipidemias associated with premature cardiovascular disease is crucial during childhood to delay or prevent the atherosclerotic process. Guidelines for the diagnosis and treatment of hypercholesterolemia during pediatric age are available from the National Cholesterol Education Program. A heart-healthy diet should begin at the age of 2 yr and a large number of studies have demonstrated no adverse effects on nutritional status, growth, pubertal development, and psychological aspects in children and adolescents limiting total and saturated fat intake. Pharmacotherapy should be considered in children over 10 yr of age when LDL cholesterol concentrations remain very high despite severe dietary therapy, especially when multiple risk factors are present. The only lipid-lowering drugs recommended up to now for childhood and adolescence are resins reported to be effective and well tolerated, although compliance is very poor because of unpalatability. The use of statins is increasing and seems to be effective and safe in children, even if studies enrolled a small number of patients and evaluated efficacy and safety for short-term periods. Recently, an interesting drug represented by ezetimibe has been found that may provide cholesterol-lowering additive to that reached with statin treatment. This review provides an update on recent advances in the diagnosis, therapy, and follow-up of familial hypercholesterolemia during pediatric age and adolescence.

Clinical effects of erdosteine in the treatment of acute respiratory tract diseases in children.

Erdosteine has positive effects on mucus rheology and transport due to the active metabolite (Metabolite I) which contains a free thiol group. Erdosteine inhibits bacterial adhesiveness and has antioxidant properties. A synergistic effect of erdosteine with various antibiotics has been demonstrated in pharmacological and clinical studies. The present study was multicenter, randomized, double-blind and placebo-controlled. The aims of the study were to compare a combination of erdosteine with amoxicillin against an amoxicillin-placebo combination in pediatric patients with acute lower respiratory tract disease. A total of 158 patients (78 in the erdosteine group and 80 in the placebo group) were treated for 7 +/- 2 days. The efficacy parameters were cough (primary), polypnea, rhonchi, rales and body temperature (all measured at baseline, on Day 3 and at the end of treatment). Safety was assessed by strictly monitoring the occurrence of adverse events and using standard laboratory parameters. The results of the intention-to-treat analysis showed that the severity of cough was decreased by 47% at Day 3 in the erdosteine group with a statistically significant difference compared to placebo, the difference was still significant at the final visit. The decrease in the severity of rales was significantly greater at Day 3 in the erdosteine group than in the placebo group. The incidence of polypnea and rhonchi in the two groups showed similar decreases, an improvement mainly due to the antibiotic. No adverse events occurred and no adverse changes in laboratory parameters were observed. It is concluded that the combination of erdosteine and amoxicillin is a safe medication which is clinically superior to that of the antibiotic combined with placebo, especially in regard to the effects on cough.

High basal serum allopregnanolone levels in overweight girls.

OBJECTIVE: Several studies demonstrated that obese subjects have a hyperactive hypothalamic-pituitary-adrenal axis and that sex steroid hormones have been closely related to the regulation of adiposity, either through direct or indirect physiological mechanisms. Allopregnanolone (3alpha-hydroxy-5alpha-pregn-20-one; AP) is a circulating neuroactive steroid hormone involved in the modulation of behavioral functions, stress and neuroendocrine axis. The aim of our study was to evaluate basal serum AP levels in obese children. SUBJECTS AND MEASUREMENTS: We studied 27 normal weight (NW) and 23 overweight (OW) girls. Gonadotropins and steroid hormones were assessed in all patients. RESULTS: Basal AP concentrations in OW girls were significantly higher than in NW controls (P=0.013). There was no difference found between the other gonadal and adrenal hormones. Considering the pubertal stage, we demonstrated that obese pubertal girls presented higher AP concentrations than prepubertal and pubertal NW ones (P=0.020), and higher dehydroepiandrosterone sulfate (DHEAS) levels with respect to prepubertal obese girls, and prepubertal and pubertal NW patients (P=0.025). AP and DHEAS were significantly directly related to weight (r=0.31 and r=0.54, respectively) and body mass index (r=0.29 and r=0.34, respectively). In pubertal OW girls, a significant positive correlation between AP and DHEAS (r=0.60), A (r=0.72) and luteinizing hormone (r=0.64) levels was demonstrated. CONCLUSION: The present study demonstrates that AP is hypersecreted in children and adolescent with OW involving DHEAS concentrations, too. Our data suggest a possible role of AP in the regulation of neuroendocrine axis related to obesity. We can also speculate that in OW girls, who could manifest emotional and behavioral problems, a part of higher levels of this neuroactive steroid might act as gamma-aminobutyric acid agonist producing anxiolytic-sedative effects.

[Activity of pediatric acceptance in the Polyclinic of Modena: 1999 to 2003]. / Attività di accettazione pediatrica nel Policlinico di Modena: 1999-2003.

The activity of the pediatric emergency ward in 1999-2003 period is described. An increasing number of contacts was recorded. Most of them should be considered improper. An extra health-care information is required, specially directed to the foreign families, who recently settled in our town. A pediatric outpatient clinic for non-critical patient could cover Sundays and holidays, as in other italian centers.

[The short-stay observation unit: an experience of the Pediatric Department in Modena]. / Osservazione breve intensiva (OBI) in pediatria: l'esperienza del Policlinico di Modena.

The use of a short-stay observation unit (OBI) in a pediatric department has reduced the number of admissions. Significant cost savings and a better care for children and their families have been also achieved. During the year 2003 in our department 1759 children received OBI. 226 (12.8%) were then admitted. 1553 (87.2%) were discharged after a nine-hour mean stay. Descriptive statistics are used to outline the sample of patients and used treatments.

Hepatitis C virus (HCV) genotypes in 373 Italian children with HCV infection: changing distribution and correlation with clinical features and outcome.

BACKGROUND AND AIMS: Little is known of hepatitis C virus (HCV) genotypes in HCV infected children. This retrospective, multicentre study investigated genotype distribution and correlation with clinical features and outcome in a large series of Italian children. METHODS: Between 1990 and 2002, 373 HCV RNA positive children, consecutively recruited in 15 centres, were assayed for genotypes by a commercial line probe assay. RESULTS: The following genotype distribution pattern was recorded: genotype 1b = 41%; 1a = 20%; 2 = 17%; 3 = 14.5%; 4 = 5%; other = 2.5%. The prevalence of genotypes 1b and 2 decreased significantly (p<0.001) among children born from 1990 onwards compared with older children (46% v 70%) while the rate of genotypes 3 and 4 increased significantly (from 8% to 30%). Children infected with genotype 3 had the highest alanine aminotransferase levels and the highest rate of spontaneous viraemia clearance within the first three years of life (32% v 3% in children with genotype 1; p<0.001). Of 96 children enrolled in interferon trials during the survey, 22% definitely lost HCV RNA, including 57% of those with genotypes 2 and 3. CONCLUSION: HCV genotypes 1 and 2 are still prevalent among infected adolescents and young adults in Italy but rates of infection with genotypes 3 and 4 are rapidly increasing among children. These changes could modify the clinical pattern of hepatitis C in forthcoming years as children infected with genotype 3 have the best chance of spontaneous viraemia clearance early in life, and respond to interferon in a high proportion of cases.

Interferon treatment in children with chronic hepatitis C: long-lasting remission in responders, and risk for disease progression in non-responders.

BACKGROUND AND AIM: Large interferon-based therapeutic trials are still lacking in children with hepatitis C and the long-term safety and efficacy of interferon is unknown. This study describes the outcome of hepatitis C in 43 children enrolled in an open-label interferon trial, and were followed up to 66 months after stopping treatment. PATIENTS AND METHODS: All patients received interferon alfa2a (5MU/m(2)) thrice weekly for 6 months; children with genotype 1b received 3MU/m(2) thrice weekly for 6 additional months. RESULTS: Nine children discontinued interferon for adverse events and three were not compliant to treatment. Eight (19%, intention to treat analysis), including 2/20 (10%) with genotype 1b and 6/12 (50%) with genotypes 2 or 3, were sustained responders 12 months after stopping therapy. During further follow-up (mean+/-S.D.: 44.7+/-14.6 months), response was maintained; two non-responders cleared viremia, while a young boy progressed to cirrhosis. CONCLUSIONS: Small sample size and therapy withdrawal are the major limitations in the interpretation of our results. Nevertheless, our data, suggesting that response to interferon in children with hepatitis C is genotype-related and stable, agree with the results of large studies in adults. The outcome in non-responders was variable, including persistence of viremia and mild-moderate cytolysis (most cases), progression to cirrhosis, or eventual sustained viremia clearance.

Antitransglutaminase enzyme-linked immune-adsorbed assay in coeliac disease diagnosis: evaluation of a diagnostic algorithm.

BACKGROUND: Tissue transglutaminase is the major autoantigen recognized in the sera of coeliac patients. An enzyme-linked immune-adsorbed assay based on tissue transglutaminase was recently used to measure serum tissue transglutaminase immunoglobulins A for coeliac disease diagnosis. OBJECTIVES: To determine the sensitivity, the specificity, the positive and negative predictive values of an immunoenzymatic assay based on guinea pig tissue transglutaminase, to compare antititransglutaminase immunoenzymatic assay to the antiendomysium immunofluorescent assay, and to define a cost-effective sequence to execute serum antibody determination in coeliac patients. METHODS: We assessed for coeliac disease antibodies 91 pediatric patients with symptoms suggestive of coeliac disease, and 23 patients with coeliac disease on a gluten-free diet as controls. RESULTS: Antitransglutaminase immunoglobulins A showed 93.1% sensitivity, 93.6% specificity, 87.1% positive and 96.7% negative predictive values. Antitransglutaminase immunoglobulins A were significantly higher in antiendomysium positive subjects. Correlation between antitransglutaminase immunoglobulins A and antigliadin immunoglobulins A was not significant. DISCUSSION: Our results show that antitransglutaminase immunoenzymatic assay represents a cost-effective strategy for patients' serological evaluation and it could substitute EMA determination, which could be considered a second level evaluation.

Prevalence and clinical picture of celiac disease in italian down syndrome patients: a multicenter study.

BACKGROUND: A multicenter research study of Down syndrome patients was carried out to estimate the prevalence of celiac disease in patients with Down syndrome and to show clinical characteristics and laboratory data of Down syndrome patients. METHODS: The authors studied 1,202 Down syndrome patients. Fifty-five celiac disease patients (group 1) were compared with 55 immunoglobulin A antigliadin-positive antiendomysium antibodies-negative patients (group 2) and with 57 immunoglobulin A antigliadin-negative antiendomysium antibodies-negative patients (group 3). RESULTS: Celiac disease was diagnosed in 55 of 1,202 Down syndrome patients (4.6%). In group 1, weight and height percentiles were shifted to the left, whereas these parameters were normally distributed in groups 2 and 3. In celiac patients, diarrhea, vomiting, failure to thrive, anorexia, constipation, and abdominal distension were higher than in the other two groups. Low levels of hemoglobinemia, serum iron, and calcium were observed more frequently in group 1. The diagnosis of celiac disease was made after a mean period of 3.8 years from the initiation of symptoms. Sixty-nine percent of patients showed a classic presentation, 11% had atypical symptoms, and 20% had silent celiac disease. Autoimmune disorders were more frequent (30.9%) in group 1 than in the other two groups examined (15%; P < 0.05). CONCLUSIONS: This study reconfirms a high prevalence of celiac disease in Down syndrome. However, the diagnostic delay, the detection of atypical symptoms or silent form in one third of the cases, and the increased incidence of autoimmune disorders suggest the need for the screening of celiac disease in all Down syndrome patients.

Hepatitis B virus infection in native versus immigrant or adopted children in Italy following the compulsory vaccination.

BACKGROUND: Compulsory vaccination of children against hepatitis B virus (HBV) infection was introduced in Italy in 1991. PATIENTS AND METHODS: To evaluate the current importance of pediatric HBV infection, we studied 359 HBsAg-positive children admitted to 16 centers in Italy from 1991 to 1998. 185 patients were natives of Italy and 174 (39 immigrants and 135 adopted) came from highly endemic countries (eastern Europe: 60.9%, Asia: 16.7%, Africa: 14.9% and Central and South America: 5.7%). RESULTS: Transaminase Levels were moderately altered in both Italian (mean 134 UI/L) and foreign children (mean 168 UI/L). In total, 77% of ItaLian children and 88% of foreign children tested HBeAg positive. High transaminase levels and HBeAg positivity were more frequent in adopted children. Follow-up of 317 patients showed that the incidence of HBeAg/anti-HBe serum conversion was similar in all cohorts, but in adopted children it occurred at an earlier age and was associated with HBsAg clearance in 5%. CONCLUSION: HBV is not frequent in Italian children today, but it is common among children coming from highly endemic areas. The vaccination of nonimmune native populations must be strongly recommended.

Markers of cell death-activation in lymphocytes of vertically HIV-infected children naive to highly active antiretroviral therapy: the role of age.

BACKGROUND: Apoptosis plays a major role in depleting CD4(+) lymphocytes during infection with HIV-1. Few data exist on its role during HIV infection of children. Sensitivity of peripheral blood lymphocytes (PBLs) to apoptotic stimuli and the importance of the patient's age remain unclear. OBJECTIVES: We sought to analyze the following: (1) markers of cell death-activation (CD95, CD45 isoforms, and CD28) in PBLs from vertically HIV-infected children of different ages before highly active antiretroviral therapy; (2) changes in other PBL populations; (3) PBL sensitivity to cell death and mitochondrial damages; and (4) role of age during progression of infection. METHODS: Cell culture techniques and flow cytometry were used to analyze surface antigens, PBL susceptibility to apoptosis, or PBL susceptibility to change of mitochondrial membrane potential. RESULTS: Donor age had a strong negative correlation with numbers of CD4(+) and CD8(+) T cells. Virgin T lymphocyte (CD45RA(+), CD95(-)) levels and those of CD95(+) cells showed no correlation with the children's clinical status but did show a correlation with patient age. CD28(-) T lymphocytes were markedly augmented in HIV-infected children but were unrelated to stage of infection or age. A relevant decrease in B lymphocytes and an increase in natural killer cells were also found. Finally, PBLs from HIV-positive children had a marked tendency to undergo apoptosis and mitochondrial damage. CONCLUSION: Changes in PBL phenotype, increased expression of CD95, and high sensitivity to apoptosis suggest that a precocious aging of the immune system occurs in HIV-infected children.

High prevalence of celiac disease in Italian general population.

The worldwide increase of celiac disease prompted us to assess its prevalence in the Italian general population. The 3483 inhabitants of Campogalliano were tested for immunoglobulin A anti-endomysial antibodies. Twenty subjects showed antibody positivity and duodenal biopsy detected typical mucosal lesions of celiac disease in 17 of them; the remaining three cases had a normal villous architecture, but the finding of increased gamma/delta intraepithelial lymphocytes in all and the heterodimer DQA1*0501, DQB1*0201 in two of them was consistent with potential celiac disease. Only one patient had an overt malabsorption syndrome, characterized by diarrhea, weight loss, and severe weakness. In eight subjects atypical symptoms of celiac disease, such as dyspepsia and depression, were present, whereas the remaining subjects were silent. Celiac disease was more frequent in younger age groups. Our cross-sectional design study demonstrates that celiac disease prevalence in the Italian general population is 4.9 per 1000 (95% CI 2.8-7.8), increasing up to 5.7 per 1000 (95% CI 3.5-8.8) with the inclusion of potential cases.