Daily assessment of arterial distensibility in a pediatric population before and after smoking cessation

OBJECTIVES: Cigarette smoking is an important modifiable cardiovascular risk factor associated with increased stiffness of the large arteries in adulthood. This study aimed to 1) evaluate arterial distensibility and echocardiographic measures in adolescent smokers before and after participation in a successful smoking cessation program and to 2) compare the findings obtained with data from a control population of healthy non-smokers. METHODS: A total of 31 young smoking subjects (58.1% male; range: 11-18 years old; mean: 16.5±1.4 years old; mean tobacco consumption: 2.6±0.6 years) were examined before commencing and after taking part for at least 1 year in a smoking cessation program (mean: 1.4±0.3 years). Arterial stiffness was measured using the previously validated QKd100-60 method. Twenty-four-hour ambulatory blood pressure monitoring and transthoracic echocardiography were also performed. RESULTS: (Smokers before abuse cessation vs. smokers after abuse cessation) systolic blood pressure: p<0.004; diastolic blood pressure: p<0.02; mean blood pressure: p<0.01; QKd100-60 value: 183±5 vs. 196±3 msec, p<0.009; p = ns for all echocardiographic parameters. (Smokers after abuse cessation vs. controls) systolic blood pressure: p<0.01; diastolic blood pressure: p<0.03; mean blood pressure: p<0.02; QKd100-60 value: 196±3 vs. 203±2 msec, p<0.04; p<0.02, p<0.01, and p<0.05 for the interventricular septum, posterior wall, and left ventricular mass, respectively. CONCLUSIONS: Despite successful participation in a smoking cessation program, arterial distensibility improved but did not normalize. This finding underlines the presence of the harmful effect of arterial rigidity in these individuals, despite their having quit smoking and their young ages, thus resulting in the subsequent need for a lengthy follow-up period. .

Hypoxia/reoxygenation-induced myocardial lesions in newborn piglets are related to interindividual variability and not to oxygen concentration

OBJECTIVE: Evaluation of myocardial histological changes in an experimental animal model of neonatal hypoxiareoxygenation. METHODS: Normocapnic hypoxia was induced in 40 male Landrace/Large White piglets. Reoxygenation was initiated when the animals developed bradycardia (HR <60 beats/min) or severe hypotension (MAP <15 mmHg). The animals were divided into four groups based on the oxygen (O2) concentration used for reoxygenation; groups 1, 2, 3, and 4 received 18%, 21%, 40%, and 100% O2, respectively. The animals were further classified into five groups based on the time required for reoxygenation: A: fast recovery (<15 min); B: medium recovery (15-45 min); C: slow recovery (45-90 min); D: very slow recovery (>90 min), and E: nine deceased piglets. RESULTS: Histology revealed changes in all heart specimens. Interstitial edema, a wavy arrangement, hypereosinophilia and coagulative necrosis of cardiomyocytes were observed frequently. No differences in the incidence of changes were observed among groups 1-4, whereas marked differences regarding the frequency and the degree of changes were found among groups A-E. Coagulative necrosis was correlated with increased recovery time: this condition was detected post-asphyxia in 14%, 57%, and 100% of piglets with fast, medium, and slow or very slow recovery rates, respectively. CONCLUSIONS: The significant myocardial histological changes observed suggest that this experimental model might be a reliable model for investigating human neonatal cardiac hypoxia-related injury. No correlation was observed between the severity of histological changes and the fiO2 used during reoxygenation. Severe myocardial changes correlated strictly with recovery time, suggesting an unreported individual susceptibility of myocardiocytes to hypoxia, possibly leading to death after the typical time-sequence of events.

Cranberry in children: prevention of recurrent urinary tract infections and review of the literature

Urinary tract infections (UTI) are common in childhood. In 30-50 percent of children with UTI the infections occur recurrently, especially in those with vesicoureteral reflux (VUR), neurogenic bladder (NB), previous cystitis or pyelonephritis and malformative uropathies. To reduce the likelihood of UTI, antibiotic prophylaxis has been regarded as the therapeutic standard for many years. However, the disadvantage of long-term antibiotic therapy is the potential for development of collateral effects and resistant organisms in the host. Such reasons have induced scientists to search for alternative modalities of UTI prevention and have contributed to determining the increasing desire for "naturalness" of the population and preventing excessive medication. The use of cranberry fulfils these needs by potentially replacing or enhancing traditional procedures. The purpose of this study was to assess the effectiveness of cranberry in preventing UTI in pediatric populations. We searched Pubmed, the Cochrane Central Register of Controlled Trials and Internet. Cranberry in patients with previous UTI was evaluated in three studies, cranberry in patients with VUR in three studies and four studies analyzed the efficacy of cranberry in children with NB. In seven of nine studies cranberry had a significant effect in preventing UTI.

Should we definitively abandon prophylaxis for patent ductus arteriosus in preterm new-borns?

Although the prophylactic administration of indomethacin in extremely low-birth weight infants reduces the frequency of patent ductus arteriosus and severe intraventricular hemorrhage, it does not appear to provide any long-term benefit in terms of survival without neurosensory and cognitive outcomes. Considering the increased drug-induced reduction in renal, intestinal, and cerebral blood flow, the use of prophylaxis cannot be routinely recommended in preterm neonates. However, a better understanding of the genetic background of each infant may allow for individualized prophylaxis using NSAIDs and metabolomics.