Pityriasis alba: a study of pathogenic factors

BACKGROUND: The aetiology of pityriasis alba (PA), a common dermatosis in childhood, is still controversial. The objective of this study was to assess the possible aetiopathogenic factors of this disease in infants. METHODS: Forty-four patients with PA and 31 healthy children were examined and compared. Personal hygiene habits, sun exposure, presence of Staphylococcus aureus in nasal fossae and presence of major or minor signs of atopy were assessed during anamnesis and physical examination. Susceptibility to ultraviolet (UV) B radiation was measured by the onset of a contact hypersensitivity reaction to diphenylcyclopropenone in individuals sensitized in previously irradiated areas. RESULTS: The prevalence of PA was higher in individuals with darker skin, in high phototype categories, as well as in males. The number of daily baths and sun exposure between 10.00 h and 15.00 h were significantly higher in the PA group when compared with controls (P = 0.03 and P = 0.0015, respectively). The presence of atopy signs was more common in pityriasis patients (P = 0.002). Susceptibility to UVB radiation was 29.6% in the PA group vs. 29.0% in the control group; nevertheless, important differences were found after stratification in order to control possible confounding factors. The presence of S. aureus in the nostrils was equal in both groups. CONCLUSIONS: Our results confirm that PA, in our population, is more prevalent in males and in individuals in higher phototype categories. In those with inadequate personal hygiene and sun exposure habits the disease is more accentuated, demonstrating that the xerosis presenting in individuals with atopic diathesis is an important element in the development of the disease. S. aureus is not an important aetiopathogenic factor in PA. Susceptibility to UVB becomes important when related to the patient's phototype.     

Biochemical changes caused by the infusion into the substantia nigra of the rat of MPTP and related compounds which antagonise dihydropteridine reductase

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), 1-methyl-4-phenylpyridinium bromide (MPP+), 1-methyl-4-(3', 4'-dihydroxyphenyl)pyridinium bromide, 4-(3',4'-dihydroxyphenyl)pyridine, 4-phenyl-1,2,3,6-tetrahydropyridine and 4-(3',4'-dimethoxyphenyl)1,2,3,6-tetrahydropyridine were infused bilaterally into the substantia nigra of the rat (10 micrograms/24 hr for 4 days). The ability to inhibit spontaneous locomotor activity and to reduce levels of neurotransmitters and metabolites in the nigrostriatal system (striatum, substantia nigra) was compared with activity to inhibit dihydropteridine reductase (DHPR) in vitro. The compound MPP+ was most effective to reduce motor responding and to decrease levels of dopamine, DOPAC and HVA (50-56%) in the striatum in addition to reducing levels of dopamine, DOPAC, noradrenaline, serotonin and 5-HIAA (42-86%) in the substantia nigra, yet MPP+ has been shown to have very weak ability to inhibit DHPR. In contrast, 4-(3',4'-dihydroxyphenyl)pyridine and 1-methyl-4-(3',4'-dihydroxyphenyl)pyridinium bromide were in the order of 10(4) and 2 X 10(5) times, respectively, more potent than MPP+ to inhibit DHPR in vitro, but these compounds failed to modify dopamine neuronal function when assessed in vivo. Therefore, there would not appear to be any correlation between the ability to modify dopamine neuronal function, as assessed behaviourally or biochemically, and ability to inhibit DHPR in synaptosomes from the striatum of the rat in vitro.     

The epidemiology of Neisseria meningitidis meningitis in Togo during 2003-2005

Few reports documenting the epidemiology of Neisseria meningitidis (Nm) serogroup W135 exist, and none from Togo. During 2003-2005, we conducted acute bacterial meningitis surveillance at three major reference hospitals in Togo. Of 116 Nm identified, 83 (71%) were NmA, 23 (20%) were NmW135, and 10 (9%) did not have a serogroup identified. Nine percent of NmW135 cases and 35% of NmA cases occurred among those aged 15 years or older. The two hospitals in central Togo reported 23% of all Nm cases and 78% of NmW135 cases. Twelve of the 23 NmW135 cases occurred during February-March 2003, while the remaining 11 occurred sporadically over the remaining 18 months of the study. NmW135 meningitis showed pronounced temporal and geographic clustering and occurred almost exclusively among those younger than 15 years old. By the 2004-2005 epidemic season, NmW135 had largely disappeared from Togo for unknown reasons.     

Phylogenetic analysis of human G9P[8] rotavirus strains circulating in Jiangsu,China between 2010 and 2016

Rotavirus A (RVA) is the leading cause of acute viral gastroenteritis in children under 5 years of age worldwide. G9P[8] is a common RVA genotype that has been persistently prevalent in Jiangsu, China. To determine the genetic diversity of G9P[8] RVAs, 7 representative G9P[8] strains collected from Suzhou Children’s Hospital between 2010 and 2016 (named JS2010‐JS2016) were analyzed through whole‐genome sequencing. All evaluated strains showed the Wa‐like constellation G9‐P[8]‐I1‐R1‐C1‐M1‐A1‐N1‐T1‐E1‐H1. Furthermore, phylogenetic analysis revealed that the VP7 genes of all strains clustered into lineage G9‐III and G9‐VI. With the exception of strain JS2012 (P[8]‐4), the VP4 sequences of all strains belonged to the P[8]‐3 lineage. Sequencing further revealed that amino acid substitutions were present in the antigenic regions of the VP7 and VP4 genes of all strains. Moreover, there were multiple substitutions in antigenic sites I and II of the nonstructural protein 4 (NSP4) genes, whereas the other NSP genes were relatively conserved. In conclusion, our phylogenetic analysis of these 7 G9P[8] strains suggests that RVA varied across regions and time. Therefore, our findings suggest that continued surveillance is necessary to explore the molecular evolutionary characteristics of RVA for better prevention and treatment of acute viral gastroenteritis.     

The significance of the left atrial appendage in rheumatic heart disease.

The possible diagnostic value of an enlarged left atrial appendage (LAA) on the posterior-anterior or right anterior oblique chest film as a means of implicating a rheumatic etiology for mitral valve disease in children was investigated. Chest films were examined without prior knowledge of clinical or laboratory data, and the results were later correlated with this information in 113 children and adolescents. The clinical and laboratory data included application of the modified Jones criteria for the diagnosis of acute rheumatic fever, streptococcal antibody titers and clinical and cardiac catheterization findings. In children with mitral valve disease, our data suggest that as enlarged LAA, especially in the presence of pulmonary venous obstruction, is characteristic of rheumatic heart disease. This finding appears to be particularly useful, in conjunction with streptococcal antibody studies, in distinguishing rheumatic from nonrheumatic patients with mitral insufficiency.     

Neuromuscular comorbidity,heart failure,and atrial fibrillation as prognostic factors in left ventricular hypertrabeculation/noncompaction

Background

There is some controversy concerning the prognosis of patients with left ventricular hypertrabeculation/noncompaction (LVHT). LVHT is frequently associated with neuromuscular disorders (NMDs). The aim of this study was to assess cardiac and neurological findings as predictors of mortality in patients with LVHT.

Patients and methods

The study included patients with LVHT diagnosed between June 1995 and January 2014 in one echocardiographic laboratory. They underwent a baseline cardiologic examination and were invited for a neurological examination. Between January and February 2014, their survival status was assessed.

Results

LVHT was diagnosed in 220 patients (68 female, aged 52?±?17 years) with a prevalence of 0.35?%/year. During a follow-up of 72?±?61 months, 65 patients died. The mortality was 5?%/year. A neurological investigation was performed on 173 patients (79?%) and revealed specific NMDs in 31 (14?%), NMD of unknown etiology in 103 (47?%), and normal findings in 39 (18?%) patients. In multivariate analysis, the predictors of mortality were increased age (p?=?0.0001), presence of a specific NMD (p?=?0.0062) or NMD of unknown etiology (p?=?0.0062), heart failure NYHA III (p?=?0.0396), atrial fibrillation (p?=?0.0022), and sinus tachycardia (p?=?0.0395).

Conclusions

LVHT patients should undergo systematic neurological examinations. Whether an optimal therapy of heart failure and atrial fibrillation will improve the prognosis of LVHT patients needs to be addressed in further studies.