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ABSTRACTAcinetobacter baumanniiis a hospital-acquired pathogen that shows an extraordinary capacity to stay in the hospital environment. Adherence of the bacteria to eukaryotic cells or to abiotic surfaces is the first step for establishing an infection. The A. baumanniistrain AbH12O-A2 showed an exceptional ability to adhere to A549 epithelial cells. The AbFhaB/FhaC 2-partner secretion (TPS) system involved in adhesion was discovered after the screening of the recently determined A. baumanniiAbH12O-A2 strain genome (CP009534.1). The AbFhaB is a large exoprotein which transport to the bacterial surface is mediated by the AbFhaC protein. In the present study, the role of this TPS system in the AbH12O-A2 adherence phenotype was investigated. The functional inactivation of this 2-partner secretion system was addressed by analyzing the outer membrane vesicles (OMV) proteomic profile from the wild-type strain and its derivative mutant AbH12O-A2ΔfhaC demonstrating that AbFhaB is no longer detected in the absence of AbFhaC. Scanning electron microscopy (SEM) and adhesion experiments demonstrated that inactivation of the AbFhaB/FhaC system significantly decreases bacterial attachment to A549 alveolar epithelial cells. Moreover, it has been demonstrated that this 2-partner secretion system is involved in fibronectin-mediated adherence of the A. baumanniiAbH12O-A2 isolate. Finally, we report that the AbFhaB/FhaC system is involved in virulence when tested using invertebrate and vertebrate hosts. These data suggest the potential role that this AbFhaB/FhaC secretion system could play in the pathobiology of A. baumannii.

Abstract: Indigenous wine hydrolytic enzymes come from both grape berries and the microorganisms involved in the fermentation process. The levels of these enzymes in wine vary according to the elaboration period and to wine aging; among them invertase and polygalacturonase are enzymes fairly resistant to denaturation and with utility to determine wine aging. Invertase may be employed as a marker of wine aging and it may be also used for differentiating wines from different regions of origin and different grape varieties. Polygalacturonase is a good indicator useful to differentiate the year of harvesting for wines elaborated with the same grape variety. Both enzymes may possibly be used as indicators of potentially fraudulent “aging-accelerated” processes.

A collection of malolactic bacteria isolated from musts and wines of northwestern Spain (Rías Baixas) was used to determine their ability to produce aryl β-D-glucosidases. A β-glucosidase (EC 3.2.1.21) was purified to homogeneity from cell-free extracts of a strain of Lactobacillus plantarum. The enzyme had a molecular mass of about 40 kDa, as determined by molecular-exclusion chromatography. The enzyme was most active at pH 5.0, and was stable between pH 4.5 and 7.5. The optimum temperature was 45 °C and the enzyme was active against a wide range of aryl β-glucosides and β-linked disaccharides. The Kmand Vmaxvalues for 4-nitrophenyl-β-D-glucopyranoside were 1.82 mM and 4.89 nmol/ml/min, respectively.

: The synthesis of carotenoids begins with the formation of a phytoene from geranylgeranyl pyrophosphate, a well conserved step in all carotenogenic organisms and catalyzed by a phytoene synthase, an enzyme encoded by the crtB (spy) genes. The next step is the dehydrogenation of the phytoene, which is carried out by phytoene dehydrogenase. In organisms with oxygenic photosynthesis, this enzyme, which accomplishes two dehydrogenations, is encoded by the crtP genes. In organisms that lack oxygenic photosynthesis, dehydrogenation is carried out by an enzyme completely unrelated to the former one, which carries out four dehydrogenations and is encoded by the crtI genes. In organisms with oxygenic photosynthesis, dehydrogenation of the phytoene is accomplished by a ζ-carotene dehydrogenase encoded by the crtQ (zds) genes. In many carotenogenic organisms, the process is completed with the cyclization of lycopene. In organisms exhibiting oxygenic photosynthesis, this step is performed by a lycopene cyclase encoded by the crtL genes. In contrast, anoxygenic photosynthetic and non-photosynthetic organisms use a different lycopene cyclase, encoded by the crtY (lyc) genes. A third and unrelated type of lycopene β-cyclase has been described in certain bacteria and archaea. Fungi differ from the rest of non-photosynthetic organisms in that they have a bifunctional enzyme that displays both phytoene synthase and lycopene cyclase activity. Carotenoids can be modified by oxygen-containing functional groups, thus originating xanthophylls. Only two enzymes are necessary for the conversion of β-carotene into astaxanthin, using several ketocarotenoids as intermediates, in both prokaryotes and eukaryotes. These enzymes are a β-carotene hydroxylase (crtZ genes) and a β-carotene ketolase, encoded by the crtW (bacteria) or bkt (algae) genes.

Abstract: Ventriculoperitoneal shunting constitutes the standard procedure for draining cerebrospinal fluid (CSF) in children with hydrocephalus. Ventriculoatrial and ventriculopleural shunting are alternative methods of CSF drainage, which have gained less acceptance. Ventriculopleural shunts are seldom used owing to justified fears of pneumothorax and symptomatic effusions of CSF. The addition of an antisiphon device to standard shunt systems seems to have prevented CSF pleural effusion. From 1988 to 1998, we treated each of six hydrocephalic children with a ventriculopleural shunt. In five cases we used new-technology valves designed to prevent the effects of siphoning with current differential pressure valves. Peritoneal adhesions, recent peritonitis, ascites, and obstruction of a previous ventriculoatrial shunt were the indications for pleural shunting. After a mean follow-up period of 2.5 years all shunts were functioning adequately. Only one patient showed transient symptoms of CSF overdrainage, which were corrected by up-grading the valve setting with the magnet. A late death was unrelated to the pleural shunting procedure. The use of valves of a new design designed to prevent overdrainage seems to account for the satisfactory outcomes observed in this series. We suggest that ventriculopleural shunting should be considered as the preferred alternative to peritoneal drainage in children with intra-abdominal adhesions or with a history of recent peritoneal infection.

The Walker-Warburg syndrome (WWS) is a lethal complex of the central nervous system and the eyes. At present its cause is unknown, but clinical evidence strongly suggests that it is an autosomalrecessively inherited disorder. We report a series of nine children with WWS. The diagnosis was established by the detection of lissencephaly, hydrocephalus, and cerebellar malformation on computed tomography. All children exhibited profound psychomotor retardation and ocular abnormalities (in their anterior or posterior eye chambers). The existence of an occipital encephalocele in eight cases was the main diagnostic clue to WWS. Six patients were investigated for the presence of congenital muscular dystrophy, which was confirmed in only four of them. There were no patients with a cleft lip or palate. We studied the incidence of WWS in Spain and estimated it at 0.21 cases per 10 000 live-born children. In our series, WWS was prevalent in the Spanish gypsy population. Consanguinity was present in five of seven affected families. In a case of preganancy with twins, one of the siblings was unaffected. Eight patients were treated with ventriculoperitoneal shunts and seven underwent encephalocele repair. Histological study of the excised encephaloceles demonstrated two different patterns. Interestingly, one of the infants showed coronal craniosynostosis. Finally, we include in the appendix, for completeness, a report of the case of the sibling of a WWS patient with acrania-exencephaly.

Summary Classically meningiomas present and evolve with a progressive course. Meningiomas manifest themselves mainly in middle and old age when the incidence of strokes is higher. The authors report three instances of meningioma with acute haemorrhagic onset. The clinical picture of our cases consisted of subarachnoid bleeding, subdural heamatoma and intracerebral haemorrhage respectively. The diagnostic difficulties encountered when assessing these patients are discussed. The current literature regarding meningioma associated with haemorrhage is reviewed. One of our cases seems to be the fisrt reported case of subarachnoid haemorrhage originating from a meningioma of the petrous bone.

Dermoid tumours in children usually occur in two locations: at the anterior fontanelle and on the occipital squama. An exceptional site of origin for a posterior fossa dermoid cyst is the extradural space. There are only six previous cases of this situation reported in the literature. A series of 103 subscalp and calvarial masses in children were reviewed and three children are reported with extradural dermoids of the posterior fossa, which communicated with the skin through midline occipital dermal sinuses. All three children were seen after the rapid growth or the formation of an abscess in a previously noted occipital subcutaneous mass present since birth. Although computed tomography or magnetic resonance imaging showed the dermal sinus and the intracranial tumour, these studies were unable to ascertain the intradural or extradural nature of the tumours, their exact origin only being established at operation. Histopathological study showed preclinical signs of infection in the two patients that had not yet formed an abscess. It is suggested that early neurosurgical treatment of these neoplasms should be done to prevent the development of severe intracranial infection. The previously reported simplicity of surgical removal of occipital extradural dermoids was not confirmed in this series.

Abstract: Weapon injuries other than gunshot wounds or low-velocity stab wounds to the head are extremely rare. We report the case of a 6-year-old girl who sustained a penetrating craniocerebral injury after being accidentally shot with an underwater fishing harpoon. This mechanism of injury seems to share characteristics of both high- and low-velocity projectiles. We discuss the management of this unusual injury in a child, remarking that foreign body removal in these cases must be carried out following the original direction of the projectile trajectory. We review the current literature on craniocerebral injuries caused by similar objects, especially those occurring in children.

The authors report the case of a 5-year-old girl who presented with a parietal midline subscalp lesion. Skull radiographs demonstrated a lytic lesion surrounded by a sclerotic rim that resembled a dermoid cyst of the cranium. Histopathological analysis proved that the lesion was a benign osteoblastoma. As in other calvarial masses of uncertain nature, after diagnostic work-up, we recommend surgical excision both for diagnosis and for treatment.

A simple method for downlink interference estimation in UMTS is presented. Unlike other preceding models, the proposed method provides an analytical solution.

Atretic cephaloceles are usually detected at birth. Recently we treated a 38-year-old man with one of these lesions, apparently the first report of this occurrence in an adult.

Maize hybrids expressing the Cry1F toxin provide efficient control of lepidopteran pests. The Mediterranean corn borer, Sesamia nonagrioides (Lefèvre), is one of the most damaging pests of maize in the Mediterranean basin. In this work we firstly determined the efficacy of maize hybrids expressing the Cry1F toxin (event TC1507) to control neonates of S. nonagrioides. Leaf tissue feeding bioassays revealed that TC1507 maize is highly effective against this pest, and the percentage mortality obtained was comparable to that obtained with a Cry1Ab-expressing maize hybrid (Compa CB, event 176), which is known to be highly efficacious against S. nonagrioides. Secondly, interpopulation variation in the susceptibility to the Cry1F insecticidal protein was established for nine field-collected populations of S. nonagrioides (three Spanish, two French, two Italian, one Greek, and one Turkish). Estimates of the susceptibility of larvae to the Cry1F toxin showed low variability in lethal concentrations and growth inhibition concentrations among field populations. Moreover, no significant differences were found when they were grouped by geographical areas [Western Mediterranean (Spain and France) versus Eastern Mediterranean (Italy, Greece and Turkey)] or by history of exposure to Bt plants (Spanish vs. other populations). Therefore, the minor differences found in field populations can be attributed to natural variation in sensitivity to Cry1F. The importance of establishing baselines of susceptibility for resistance detection is discussed. Future changes in susceptibility of S. nonagrioides populations to Cry1F could be documented based on this baseline data.