Analysis of perceived risk and satisfaction with telematic follow-up in patients and families of congenital diaphragmatic hernia patients during SARS-CoV-2 pandemia

BACKGROUND

The impact of COVID-19 in families and patients with congenital diaphragmatic hernia (CDH) is unknown, this situation has generated uncertainty not only in family members but also in the optimal outpatient follow-up. Telehealth has become a fundamental tool for the follow-up during the pandemic. The objective of this survey is to evaluated the impact of SARS-CoV-2 in families and patients with CDH and the satisfaction with telematic follow-up.

METHODS

Telephone survey of patient's caregivers with CHD, aged 1-16 years, followed in neonatal surgery outpatients, from January 31, 2020 to November 15, 2020. The ethical clearance for this study was taken from the Clinical Research Ethics Committee of our Research Institute vide letter number VHIR/239283/01.01.2021.

RESULTS

81 surveys of 100 patients with active follow-up were carried out. There were no refusals in any contacted parents. There were 30 contacts (37%), 44.8% at school and 27.6% from cohabiting family members. Four infections (4.9%) were diagnosed, half symptomatic. In 40 patients (49.4%) the follow-up was telematic, with a mean score of 3.1±1.3 out of 5. For future controls, 65% prefer presential follow-up, 25% alternate and 10% telematics. 50.6% reported greater anxiety and 34.6% (28/81) extreme measures of isolation, being more accentuated in the group of 3-6 years (p<0.05).

CONCLUSION

The impact of COVID19 in patients with CHD is not greater than in the general pediatric population. Although the incorporation of the telehealth was well valued, most of the caregivers prefer the face-to-face outpatient follow-up.

Duodenal atresia with apple peel associated with congenital diaphragmatic hernia: an exceptional case and a literature review

INTRODUCTION

Duodenal atresia associated with apple peel is extremely rare. Duodenal atresia occurs as a result of absence of recanalization at an early stage, whereas intestinal atresia is seemingly due to vascular causes at later stages. The presence of abnormalities associated with diaphragmatic hernia is frequent, but association with duodenal atresia has been little explored.

CASE REPORT

This is the case of a female neonate born at gestational week 31, with duodenal atresia and apple peel, associated with left diaphragmatic hernia and major heart disease. An abdominal muscle flap was performed for diaphragmatic defect closure purposes, and duodenojejunal anastomosis was carried out following resection of part of the non-viable apple peel.

DISCUSSION

To our knowledge, this is the first case described with this rare association. The combination of duodenal atresia and apple peel had been previously described 11 times. However, the association of both with congenital diaphragmatic hernia had not been reported yet.

Minimally invasive surgery for pediatric dumbbell neuroblastoma: systematic literature review and report of a single-stage neurosurgical and thoracoscopic approach

INTRODUCTION

Traditional surgical strategies for dumbbell neuroblastoma entail, among others, high risk of spinal deformity. Less invasive procedures might reduce these sequelae, however, there is small evidence comparing different strategies. Indications of minimally invasive surgery in neuroblastoma are still developing. Our aim is to identify and analyze different surgical approaches described in the recent literature and to suggest a minimally invasive option.

METHODS

A systematic review of the literature was conducted in PubMed (Jan 2000-Dec 2021) to identify reports describing surgical resection of dumbbell neuroblastoma in children, according to the PRISMA guidelines. Only full-text articles were included.

RESULTS

7 articles met the inclusion criteria which, added to the present case, represent a total of 43 patients. All were retrospective studies, most of them small series. Tumor location was mostly thoracic. Most of combined approaches were performed in two stages. Spinal deformity after surgery was reported in 3 patients. Minimally invasive approach was described in only one paper, with no reported cases of its use in a single-stage combined surgery. We also report, to our knowledge, the first single-stage posterior neurosurgical approach combined with thoracoscopy for resection of a dumbbell neuroblastoma in an infant.

CONCLUSION

Surgical resection of dumbbell neuroblastomas is challenging. There is no consensus on best surgical approach. Dumbbell tumors should not be considered a contraindication for minimally invasive surgery. A single stage and minimally invasive strategy is proposed.

miRNA-7 and miRNA-324-5p regulate alpha9-Integrin expression and exert anti-oncogenic effects in rhabdomyosarcoma

The prognosis of patients with metastatic rhabdomyosarcoma (RMS), the most common type of soft tissue sarcoma in children, is poor and no strategies have been identified to improve their dismal prognosis. Alpha-9 integrin (ITGA9) plays a particularly crucial role in cancer progression and invasiveness. Despite the consensus on the remarkable pro-oncogenic potential of this protein, the miRNA-mediated regulation of ITGA9 has barely been studied to date. In the present study, miR-7 and miR-324-5p were selected as the best candidates after a screening to find ITGA9 regulators, and their effects on cell proliferation and invasion in RMS are described and characterized for the first time. Interestingly, the overexpression of both miRNA produced a clear impairment of cell proliferation, while miR-7 also induced a remarkable drop in cell invasion. Furthermore, the stable overexpression of both miRNA was found to reduce tumor growth in orthotopic RMS models and miR-7 was able to impair metastatic lung colonization. Consequently, we conclude that miR-7 and miR-324-5p show anti-oncogenic and anti-metastatic potential, thereby opening up the possibility of being used as novel therapeutic tools to avoid RMS progression.

[Pilot experience with indocyanine green navigation in pediatric surgery]

INTRODUCTION

Indocyanine Green (ICG) fluorescence is a new tool for navigated minimal invasive and open surgery, with multiple possible uses, that can increase safety and improve surgical results, facilitating intraoperative decision making. We hereby present our pilot series using ICG navigation in different procedures of pediatric surgery.

MATERIAL AND METHODS

As a proof of concept, between May 2017 and March 2019, we have used this technique as a help for decision making in these scenarios: visualization of the biliary tract, vascular and lymphatic structures, neoplastic tissue and other anatomic landmarks. The route of administration, timing and dosage changed depending on the indication. A 30º optic, with a conventional and near-infrared light emitter, connected to a high definition system specially equipped was used.

RESULTS

We considered that the technique might be useful in 20 patients (22 procedures): 6 involving the biliary tract (5 cholecystectomies, 1 choledochal stenosis), 9 oncologic procedures (5 laparoscopic and 4 open), 7 miscellanea (pulmonary nodule resections, long-gap esophageal atresia, anastomotic leak, etc). There were no complications regarding ICG administration. We considered that the system provided relevant information or affected intraoperative decision making in 90% of the cases.

CONCLUSIONS

ICG navigation was easy to perform and complication free. Our preliminary results suggest that ICG navigation, in open and endoscopic procedures, might provide a qualitative leap regarding safety and facilitate the performance of certain pediatric surgical procedures, particularly in oncology, liver surgery and neonatal surgery.

Uncovering Bax inhibitor-1 dual role in the legume-rhizobia symbiosis in common bean roots

Bax-inhibitor 1 (BI-1) is a cell death suppressor conserved in all eukaryotes that modulates cell death in response to abiotic stress and pathogen attack in plants. However, little is known about its role in the establishment of symbiotic interactions. Here, we demonstrate the functional relevance of an Arabidopsis thaliana BI-1 homolog (PvBI-1a) to symbiosis between the common bean (Phaseolus vulgaris) and Rhizobium tropici. We show that the changes in expression of PvBI-1a observed during early symbiosis resemble those of some defence response-related proteins. By using gain- and loss-of-function approaches, we demonstrate that the overexpression of PvBI-1a in the roots of common bean increases the number of rhizobial infection events (and therefore the final number of nodules per root), but induces the premature death of nodule cells, affecting their nitrogen fixation efficiency. Nodule morphological alterations are known to be associated with changes in the expression of genes tied to defence, autophagy, and vesicular trafficking. Results obtained in the present work suggest that BI-1 has a dual role in the regulation of programmed cell death during symbiosis, extending our understanding of its critical function in the modulation of host immunity while responding to beneficial microbes.

Molecular Features and mRNA Expression of the Receptor for Activated C Kinase 1 from Symbiodinium microadriaticum ssp. microadriaticum During Growth and the Light/Dark cycle

Two genes of the RACK1 homolog from the photosynthetic dinoflagellate Symbiodinium microadriaticum ssp. microadriaticum (SmicRACK1), termed SmicRACK1A and SmicRACK1B, were found tandemly arrayed and displayed a single synonymous substitution (T/C) encoding threonine. They included two exons of 942 bp each, encoding 313 amino acids with seven WD-40 repeats and two PKC-binding motifs. The protein theoretical mass and pI were 34,200 Da and 5.9, respectively. SmicRACK1 showed maximum identities with RACK1 homologs at the amino acid and nucleotide level, respectively, of 92 and 84% with S. minutum, and phylogenetic analysis revealed clustered related RACK1 sequences from the marine dinoflagellates S. minutum, Heterocapsa triquetra, Karenia brevis, and Alexandrium tamarense. Interestingly, light-dependent regulatory elements were found both within the 282 bp SmicRACK1A promotor sequence, and within an intergenic sequence of 359 nucleotides that separated both genes, which strongly suggest light-related functions. This was further supported by mRNA accumulation analysis, which fluctuated along the light and dark phases of the growth cycle showing maximum specific peaks under either condition. Finally, qRT-PCR analysis revealed differential SmicRACK1 mRNA accumulation with maxima at 6 and 20 d of culture. Our SmicRACK1 characterization suggests roles in active growth and proliferation, as well as light/dark cycle regulation in S. microadriaticum.

Thoracic wall reconstruction with bioabsorbable plates in pediatric malignant thoracic wall tumors

AIM

Childhood malignant chest wall tumors may require extensive surgical resection and reconstruction with musculoskeletal flaps or non-resorbable prosthetic materials. Implant-related complications and scoliosis often occur. This study analyzes the outcomes of chest wall reconstruction using resorbable plates as an alternative approach.

METHODS

Retrospective review (2007-2015) of patients who underwent resection of malignant primary chest wall tumors in 2 tertiary pediatric centers. Reconstruction was performed using copolymer (l-lactic and glycolic acid) plates, fixed to the ribs and surrounding structures with copolymer screws and/or polyglactin sutures.

RESULTS

Eight patients aged 10.6+2.6years were treated. There were no operative complications, and implant removal was not required in any case. Six patients received postoperative radiotherapy. Over follow-up (39.6months, range 9.4-78), chest wall shape was maintained in all, and there were no radiological artifacts. Three patients developed scoliosis (Cobb 17°-33°), but treatment was needed only in one, who had undergone hemivertebrectomy. There were no cases of local tumor relapse. One patient died because of metastatic spread.

CONCLUSIONS

Implantation of bioabsorbable l-lactic and glycolic acid copolymer plates with a relatively simple technique provided a rigid, stable reconstruction with only mild mid-/long-term complications. Resorbable plates may be a good alternative for pediatric chest wall reconstruction.

LEVEL OF EVIDENCE

IV.

[Endovascular embolization in the treatment of the pulmonary intralobar sequestration]

INTRODUCTION

Up to date the classical therapeutic approach for intralobar sequestrations (IS) has been surgical excision. However, systemic arteries embolization is presented as an alternative, and even constitutes the first line of treatment in some centers. We summarize our experience in selected cases with the aim of preserving the maximum lung parenchyma.

MATERIAL AND METHODS

Retrospective study of IS who underwent endovascular embolization at our institution between 2013 and 2014.

RESULTS

Three patients of 12, 14 and 21 months old were treated. Two patients had unilateral IS, one in the left lower lobe (LLL) and the other in the right lower lobe (RLL); the third one had bilateral lesions (a CAM-S complex in the RLL and a IS in the LII). The embolization of the four lesions was performed via right femoral artery. The case with bilateral lesions underwent thoracoscopic lobectomy of the CAM-S 7 months after embolization, finding adherences to the diaphragm. None of the patients had immediate complications and were discharged within 48 hours after embolization. In successive ultrasound and plain radiographs controls, with a follow-up of 6, 18 and 30 months, no complications were found.

CONCLUSIONS

Systemic vessels embolization is a treatment option for the treatment of IS that avoids surgery, preserves lung parenchyma and does not preclude surgical resection in case of treatment failure or presence of parenchymal lesions. Longer follow-up is needed to determine long-term effectiveness.

[Current anesthesia risk of anterior mediastinal masses]

AIM

To analyze the current risk of an anesthetic event during surgical acts in pediatric patients with anterior mediastinal masses (AMM) in a tertiary oncology center, using the previously published risk factors to plan the procedure.

MATERIALS AND METHODS

Retrospective study (2009-2015) of pediatric patients with AMM who underwent surgical procedures at debut. Published risk factors (symptoms, radiological findings), with special focus on the statistically significant ones, diagnosis, surgical and anesthetic procedure, special measures, and anesthetic events were recorded. Patients were classified as high or low-risk when airway or vascular compression or severe symptoms were present.

MAIN RESULTS

Retrospective study (2009-2015) of pediatric patients with AMM who underwent surgical procedures at debut. Published risk factors (symptoms, radiological findings), with special focus on the statistically significant ones, diagnosis, surgical and anesthetic procedure, special measures, and anesthetic events were recorded. Patients were classified as high or low-risk when airway or vascular compression or severe symptoms were present.

CONCLUSIONS

Preoperative evaluation of risk in AMM through clinical history and CT/MRI and surgical/anesthetic planning leads to excellent outcomes. The least aggressive procedures should be favored, but if needed, planned general anesthesia under experienced hands is safe even in risk patients.

[Conservative management of liver trauma and its complications: current gold-standard]

INTRODUCTION

The liver is the second most frequently involved organ in abdominal trauma in children. The aim of this study was to review the characteristics of liver traumas (LT) in children, its treatment and complications.

MATERIAL AND METHODS

Retrospective study of patients with LT treated between 2010-2014. We analyzed data regarding diagnosis, conservative management (CM), complications and treatment.

RESULTS

Twenty-four patients of LT with a mean age of 9.8 years (SD: 3.4) were treated at our center. Liver injury degrees according to the Organ Injury Scale of American Association for Surgery of Trauma (AAST) were: grade I (4), grade II (6), grade III (8), grade IV (5) and grade V (1). CT angiography was performed in 23 patients. Four of the six patients with initial hemodynamic instability required blood transfusion; of those, two required angioembolization for active bleeding in extrahepatic locations and a third required damage control surgery. Three patients presented late-onset complications: 2 large size bilomas which underwent spontaneous resolution and a third patient with a right biloma and section of the left bile duct who required a multidisciplinary approach. Median hospital stay was 6 days (r 1-92). With a mean follow-up of 17.75 months (SD: 16.35) (r: 2-57) long-term survival was 96%. The patient who received surgery died due to a post-traumatic brain injury.

CONCLUSION

CM seems to be the treatment of choice in LT regardless of injury degree. Surgery should be reserved for cases refractory to CM due to the associated high mortality.

[Laryngotracheal traumatic injuries (LTI) in children: when to operate?]

INTRODUCTION

Paediatric LTI is associated with significant morbid-mortality. Although historically first line treatment was surgical, conservative management is making headway. The purpose of this study was to analyze the management and surgical indications of LTI treated at our institution.

MATERIAL AND METHODS

Retrospective study of patients with LTI treated between 2007 and 2014.

RESULTS

Six out of seven patients, with a median age of 4 years (2-15), had blunt traumas and one had an open trauma. Respiratory distress, pain and subcutaneous emphysema were presented in 71.4% of the patients. Five children were intubated (3 pre-hospital care and 2 after reaching the hospital), all of them underwent fibrobronchoscopy, determining the location, the extention, and assessing the possibility of extubation. Esophagoscopy was made in 2 cases. The remaining 2 cases were bounded to observation as they did not have respiratory symptoms or progressive emphysema, precluding bronchoscopy. Conservative management was followed in 71.4% of the patients, with a 100% success rate. Conservative management criteria were no progression of emphysema or respiratory distress, regardless the degree and location of the lesions. Two patients needed surgery: one tracheoesophageal fistula caused by a button battery, and the other was a tracheal open section associated with vascular injury. Both of them recovered uneventfully.

CONCLUSIONS

If the respiratory symptoms or the emphysema do not progress, patients with LTI can be managed conservatively, regardless of size or location of the injury. Associated esophageal lesions and open injuries require surgical management. An early diagnosis is mandatory in order to minimize morbidity and mortality.

[Salivaly gland tumors in childhood: importance of an early diagnosis and treatment]

OBJECTIVE

Review of our series of salivaly gland tumors at pediatric age, given its low frequency and their higher rate of malignancy compared with the adult population.

MATERIAL AND METHODS

Retrospective study of the medical records of all pediatric patients with salivaly gland tumors treated in our center between 1998 and 2013.

RESULTS

We identified 12 patients. The most common site of tumor location was the parotid gland in 11 patients followed by the sublingual gland in 1 patient. Three patients had previous cancer and radiotherapy history. The diagnosis (histological or radiological) were: 4 hemangiomas, 2 pleomorphic adenomas, 4 mucoepidermoid carcinomas, one acinar cell carcinoma and 1 primitive neuroectodermal tumor (PNET). No patient had metastasis at diagnosis. Preoperative fine needle aspiration (FNA) was performed in 6 patients with solid masses, being diagnostic in all cases. Eight patients underwent surgery. In two cases of total parotidectomy initial neuroapraxia appeared but none had permanent facial paralysis. There were no cases of Frey syndrome. The aesthetic results were good. There was only one tumor recurrence and all patients, except one who died of leukemia relapse, survive today.

CONCLUSIONS

Salivaly gland tumors are uncommon in pediatric age but their high rate of malignancy makes it necessary to establish a rapid diagnosis. In our experience, FNA showed a high sensitivity. For malignant tumors, definitive treatment is surgical excision, preserving the facial nerve whenever possible. For vascular tumors, surgery is reserved for cases refractory to medical treatment.

Nodulin 22, a novel small heat-shock protein of the endoplasmic reticulum, is linked to the unfolded protein response in common bean

The importance of plant small heat shock proteins (sHsp) in multiple cellular processes has been evidenced by their unusual abundance and diversity; however, little is known about their biological role. Here, we characterized the in vitro chaperone activity and subcellular localization of nodulin 22 of Phaseolus vulgaris (PvNod22; common bean) and explored its cellular function through a virus-induced gene silencing-based reverse genetics approach. We established that PvNod22 facilitated the refolding of a model substrate in vitro, suggesting that it acts as a molecular chaperone in the cell. Through microscopy analyses of PvNod22, we determined its localization in the endoplasmic reticulum (ER). Furthermore, we found that silencing of PvNod22 resulted in necrotic lesions in the aerial organs of P. vulgaris plants cultivated under optimal conditions and that downregulation of PvNod22 activated the ER-unfolded protein response (UPR) and cell death. We also established that PvNod22 expression in wild-type bean plants was modulated by abiotic stress but not by chemicals that trigger the UPR, indicating PvNod22 is not under UPR control. Our results suggest that the ability of PvNod22 to suppress protein aggregation contributes to the maintenance of ER homeostasis, thus preventing the induction of cell death via UPR in response to oxidative stress during plant-microbe interactions.

Transcript profiling of common bean nodules subjected to oxidative stress

Several environmental stresses generate high amounts of reactive oxygen species (ROS) in plant cells, resulting in oxidative stress. Symbiotic nitrogen fixation (SNF) in the legume-rhizobia symbiosis is sensitive to damage from oxidative stress. Active nodules of the common bean (Phaseolus vulgaris) exposed to the herbicide paraquat (1,1'-dimethyl-4,4'-bipyridinium dichloride hydrate), which stimulates ROS accumulation, exhibited reduced nitrogenase activity and ureide content. We analyzed the global gene response of nodules subjected to oxidative stress using the Bean Custom Array 90K, which includes probes from 30,000 expressed sequence tags (ESTs). A total of 4280 ESTs were differentially expressed in stressed bean nodules; of these, 2218 were repressed. Based on Gene Ontology analysis, these genes were grouped into 42 different biological process categories. Analysis with the PathExpress bioinformatic tool, adapted for bean, identified five significantly repressed metabolic pathways related to carbon/nitrogen metabolism, which is crucial for nodule function. Quantitative reverse transcription (qRT)-PCR analysis of transcription factor (TF) gene expression showed that 67 TF genes were differentially expressed in nodules exposed to oxidative stress. Putative cis-elements recognized by highly responsive TF were detected in promoter regions of oxidative stress regulated genes. The expression of oxidative stress responsive genes and of genes important for SNF in bacteroids analyzed in stressed nodules revealed that these conditions elicited a transcriptional response.

Detailed analysis of putative genes encoding small proteins in legume genomes

Diverse plant genome sequencing projects coupled with powerful bioinformatics tools have facilitated massive data analysis to construct specialized databases classified according to cellular function. However, there are still a considerable number of genes encoding proteins whose function has not yet been characterized. Included in this category are small proteins (SPs, 30-150 amino acids) encoded by short open reading frames (sORFs). SPs play important roles in plant physiology, growth, and development. Unfortunately, protocols focused on the genome-wide identification and characterization of sORFs are scarce or remain poorly implemented. As a result, these genes are underrepresented in many genome annotations. In this work, we exploited publicly available genome sequences of Phaseolus vulgaris, Medicago truncatula, Glycine max, and Lotus japonicus to analyze the abundance of annotated SPs in plant legumes. Our strategy to uncover bona fide sORFs at the genome level was centered in bioinformatics analysis of characteristics such as evidence of expression (transcription), presence of known protein regions or domains, and identification of orthologous genes in the genomes explored. We collected 6170, 10,461, 30,521, and 23,599 putative sORFs from P. vulgaris, G. max, M. truncatula, and L. japonicus genomes, respectively. Expressed sequence tags (ESTs) available in the DFCI Gene Index database provided evidence that ~one-third of the predicted legume sORFs are expressed. Most potential SPs have a counterpart in a different plant species and counterpart regions or domains in larger proteins. Potential functional sORFs were also classified according to a reduced set of GO categories, and the expression of 13 of them during P. vulgaris nodule ontogeny was confirmed by qPCR. This analysis provides a collection of sORFs that potentially encode for meaningful SPs, and offers the possibility of their further functional evaluation.

Common bean (Phaseolus vulgaris L.) PvTIFY orchestrates global changes in transcript profile response to jasmonate and phosphorus deficiency

BACKGROUND

TIFY is a large plant-specific transcription factor gene family. A subgroup of TIFY genes named JAZ (Jasmonate-ZIM domain) has been identified as repressors of jasmonate (JA)-regulated transcription in Arabidopsis and other plants. JA signaling is involved in many aspects of plant growth/development and in defense responses to biotic and abiotic stresses. Here, we identified the TIFY genes (designated PvTIFY) from the legume common bean (Phaseolus vulgaris) and functionally characterized PvTIFY10C as a transcriptional regulator.

RESULTS

Nineteen genes from the PvTIFY gene family were identified through whole-genome sequence analysis. Most of these were induced upon methyl-JA elicitation. We selected PvTIFY10C as a representative JA-responsive PvTIFY gene for further functional analysis. Transcriptome analysis via microarray hybridization using the newly designed Bean Custom Array 90 K was performed on transgenic roots of composite plants with modulated (RNAi-silencing or over-expression) PvTIFY10C gene expression. Data were interpreted using Gene Ontology and MapMan adapted to common bean. Microarray differential gene expression data were validated by real-time qRT-PCR expression analysis. Comparative global gene expression analysis revealed opposite regulatory changes in processes such as RNA and protein regulation, stress responses and metabolism in PvTIFY10C silenced vs. over-expressing roots. These data point to transcript reprogramming (mainly repression) orchestrated by PvTIFY10C. In addition, we found that several PvTIFY genes, as well as genes from the JA biosynthetic pathway, responded to P-deficiency. Relevant P-responsive genes that participate in carbon metabolic pathways, cell wall synthesis, lipid metabolism, transport, DNA, RNA and protein regulation, and signaling were oppositely-regulated in control vs. PvTIFY10C-silenced roots of composite plants under P-stress. These data indicate that PvTIFY10C regulates, directly or indirectly, the expression of some P-responsive genes; this process could be mediated by JA-signaling.

CONCLUSION

Our work contributes to the functional characterization of PvTIFY transcriptional regulators in common bean, an agronomically important legume. Members from the large PvTIFY gene family are important global transcriptional regulators that could participate as repressors in the JA signaling pathway. In addition, we propose that the JA-signaling pathway involving PvTIFY genes might play a role in regulating the plant response/adaptation to P-starvation.

Dengue virus identification by transmission electron microscopy and molecular methods in fatal dengue hemorrhagic fever

Dengue virus is the most significant virus transmitted by arthropods worldwide and may cause a potentially fatal systemic disease named dengue hemorrhagic fever. In this work, dengue virus serotype 4 was detected in the tissues of one fatal dengue hemorrhagic fever case using electron immunomicroscopy and molecular methods. This is the first report of dengue virus polypeptides findings by electron immunomicroscopy in human samples. In addition, not-previously-documented virus-like particles visualized in spleen, hepatic, brain, and pulmonary tissues from a dengue case are discussed.

Changes in RACK1 expression induce defects in nodulation and development in Phaseolus vulgaris

RACK1 is a scaffold protein with the ability to interact in a regulated manner with a diverse number of ligands from distinct signal-transduction pathways. This assessment allowed us to infer that it may be involved in different processes such as nodulation. In a recent study we showed by silencing, that PvRACK1 has a pivotal role in cell expansion and in symbiosome and bacteroid integrity during nodule development in Phaseolus vulgaris. On the other hand, we have also observed that its over-expression provokes a dramatic phenotype in: (a) seedlings that have been exposed to heat, in which systemic necrosis is induced; and (b) in Agrobacterium rhizogenes-transformed roots, where nodulation is strongly inhibited and nodules show early senescent symptoms. These findings indicate that PvRACK1 may be an integrator of diverse signal-transduction pathways in processes as varied as nodulation, cell expansion, heat stress responses, and systemic activation of necrosis. 

[Treatment of loculated parapneumonic empyema. Video assisted thoracoscopy or fibrinolytics?]

OBJECTIVE

There is no consensus regarding the ideal treatment of loculated parapneumonic empyema (PPE). The aim of this study is to compare the effectiveness of drainage plus urokinase (DF) with video-assisted thoracoscopy (VATS).

MATERIAL AND METHODS

Retrospective review. Patients admitted with a PPE between January 2001 and July 2008. Loculated empyema was diagnosed by chest ultrasound and patients were treated with DF or VATS depending on the attending surgeon. Compared variables were: post-operative stay, total hospital stay, days of tube thoracostomy, post-operative fever and treatment failure.

RESULTS

One hundred and twenty one patients were admitted with the diagnosis of PPE. Seventeen patients were excluded from analysis because of simple parapneumonic effusions. Of the 104 patients included in the study, 47 were treated with urokinase and 57 with videothoracoscopy. No statistically significant differences (P>.05) were found between the median values in the DF and VATS groups for hospital stay (median 12 vs 12 days) or post-operative stay (median 9 vs 9 days). There were differences in duration of tube thoracostomy (median DF group 5 days, VATS, 4 days, P<.05) and in the post-operative fever (median 3 vs 2 days, p<0,05).Twenty two per cent of children needed a second procedure (14 patients of DF and 9 of VATS group, P=.09).

CONCLUSIONS

According to our experience, the results of DF and VATS for the treatment of loculated parapneumonic empyema are similar. Although there are no statistical differences, there seems to be a higher rate of failure, with the need of more procedures in the DF group. This difference does not affect the average total hospital stay.

PvRACK1 loss-of-function impairs cell expansion and morphogenesis in Phaseolus vulgaris L. root nodules

Receptor for activated C kinase (RACK1) is a highly conserved, eukaryotic protein of the WD-40 repeat family. Its peculiar β-propeller structure allows its interaction with multiple proteins in various plant signal-transduction pathways, including those arising from hormone responses, development, and environmental stress. During Phaseolus vulgaris root development, RACK1 (PvRACK1) mRNA expression was induced by auxins, abscissic acid, cytokinin, and gibberellic acid. In addition, during P. vulgaris nodule development, PvRACK1 mRNA was highly accumulated at 12 to 15 days postinoculation, suggesting an important role after nodule meristem initiation and Rhizobium nodule infection. PvRACK1 transcript accumulation was downregulated by a specific RNA interference construct which was expressed in transgenic roots of composite plants of P. vulgaris inoculated with Rhizobium tropici. PvRACK1 downregulated transcript levels were monitored by quantitative reverse-transcription polymerase chain reaction analysis in individual transgenic roots and nodules. We observed a clear phenotype in PvRACK1-knockdown nodules, in which nodule number and nodule cell expansion were impaired, resulting in altered nodule size. Microscopic analysis indicated that, in PvRACK1-knockdown nodules, infected and uninfected cells were considerably smaller (80 and 60%, respectively) than in control nodules. In addition, noninfected cells and symbiosomes in silenced nodules showed significant defects in membrane structure under electron microscopy analysis. These findings indicate that PvRACK1 has a pivotal role in cell expansion and in symbiosome and bacteroid integrity during nodule development.

A general method of protein purification for recombinant unstructured non-acidic proteins

Typical late embryogenesis abundant (LEA) proteins accumulate in response to water deficit imposed by the environment or by plant developmental programs. Because of their physicochemical properties, they can be considered as hydrophilins and as a paradigm of intrinsically unstructured proteins (IUPs) in plants. To study their biophysical and biochemical characteristics large quantities of highly purified protein are required. In this work, we report a fast and simple purification method for non-acidic recombinant LEA proteins that does not need the addition of tags and that preserves their in vitro protective activity. The method is based on the enrichment of the protein of interest by boiling the bacterial protein extract, followed by a differential precipitation with trichloroacetic acid (TCA). Using this procedure we have obtained highly pure recombinant LEA proteins of groups 1, 3, and 4 and one recombinant bacterial hydrophilin. This protocol will facilitate the purification of this type of IUPs, and could be particularly useful in proteomic projects/analyses.

[Robotic surgery: first pediatric series in Spain]

OBJECTIVES

Despite several surgical robots operating in Spain, the experience in pediatric pathology is limited. We found interesting to review the first full pediatric series in our country. We would like to share as well our views on the transition from conventional to robotic laparoscopy.

METHODS

Retrospective review of all the pediatric laparoscopic surgery assisted by the da Vinci robot (Intuitive Surgical), in our center, between April 2009 and February 2010.

RESULTS

8 patients were operated (7-15 years), with an average weight of 42 Kg (18 to 83 Kg). 11 procedures were performed: bilateral salpingo-oophorectomy (1), inguinal hernia (1), cholecystectomy (4), splenectomy (2), resection of pancreatic mass (1), fundoplication (1), adrenalectomy (1). All proceedings, except two, were completed with the robot. As complications, there was one intraoperative bleeding that required blood transfusion, and in the postoperative period, there was a surgical wound infection. There were no conversions to open surgery. The average time of preparation before surgery was 130 minutes. The three-dimensional vision and lack of tremor are the main advantages cited by all surgeons.

CONCLUSIONS

The learning curve of Robotic Surgery is shorter than that of conventional laparoscopy. Trained surgeons can perform complex procedures laparoscopically from the outset. The main difficulty in children is the proper planning of trocar placement, due to the smaller size of the surgical field. The organization of surgery is complex and success depends on close collaboration of all stakeholders.

[Cervical cystic lymphangioma: still a challenge]

INTRODUCTION

Cervical lymphangiomas can not only cause severe sequelae (aesthetic, phonatory or deglutory) but can also be life thereatening due to airway compresion or massive bleeding. This paper analyzes our surgical results, the value of prenatal diagnosis and the use of new techniques such as the EXIT procedure for airway control in sereve cases.

PATIENTS AND METHODS

We retrospectively reviewed the medical record of patients with cervical lymphangiomas treated in our center between 1986 and 2009, according to our Clinical Documentation Database. Data referred to prenatal diagnosis, intrapartum airway management, surgical procedures and morbidity, sclerosing substance infiltration and long term sequelae was analyzed.

RESULTS

Thirteen cases were identified. 53.8% of the patients were diagnosed by prenatal ultrasound, and MRI was performed in 46.1%. The tongue was affected in 30.7%, parotid glands in 38.4% and airway in 38.4%. Four EXIT procedures were carried out (nasotracheal intubation) and one emergency tracheotomy was needed. Five patients required more than one surgical prodedures, including partial glossectomy, with severe intraoperatory complications in 23% (bleeding, pharyngeal damage). In eight patients primary or adyuvant sclerotherapy was used. Three children with giant masses died, two due to intracystic bleeding and one from sepsis. Among the survivors, 50% have no sequelae.

CONCLUSIONS

Cervical lymphangiomas are a very sereve condition, not only due to possible airway compresion or massive bleeding but also becose of the severe secualaes they may cause. Tongue or parotid gland infiltration are difficult to treat. In severe cases diagnosed prenatally a close follow up in selected centers, with multidisciplinary teams consisting of obstetricians and pediatric surgeons, trained in the EXIT procedure is warranted. Despite therapeutic efforts the prognosis of large masses is still poor.

Plasma membrane integrity and survival of melanoma cells after nanosecond laser pulses

Circulating tumor cells (CTCs) photoacoustic detection systems can aid clinical decision-making in the treatment of cancer. Interaction of melanin within melanoma cells with nanosecond laser pulses generates photoacoustic waves that make its detection possible. This study aims at: (1) determining melanoma cell survival after laser pulses of 6 ns at λ = 355 and 532 nm; (2) comparing the potential enhancement in the photoacoustic signal using λ = 355 nm in contrast with λ = 532 nm; (3) determining the critical laser fluence at which melanin begins to leak out from melanoma cells; and (4) developing a time-resolved imaging (TRI) system to study the intracellular interactions and their effect on the plasma membrane integrity. Monolayers of melanoma cells were grown on tissue culture-treated clusters and irradiated with up to 1.0 J/cm². Surviving cells were stained with trypan blue and counted using a hemacytometer. The phosphate buffered saline absorbance was measured with a nanodrop spectrophotometer to detect melanin leakage from the melanoma cells post-laser irradiation. Photoacoustic signal magnitude was studied at both wavelengths using piezoelectric sensors. TRI with 6 ns resolution was used to image plasma membrane damage. Cell survival decreased proportionally with increasing laser fluence for both wavelengths, although the decrease is more pronounced for 355 nm radiation than for 532 nm. It was found that melanin leaks from cells equally for both wavelengths. No significant difference in photoacoustic signal was found between wavelengths. TRI showed clear damage to plasma membrane due to laser-induced bubble formation.

A CFSE-based assay of proliferative response of lymphocytes to stimulation with dengue viruses

Dengue viruses (DENVs) are human pathogens that constitute a significant threat worldwide. Since they up-regulate MHC class I molecules; the cell-mediated immunity may play an important role in the defense against viruses. In this work, we tested a CFSE-based assay in determining proliferative response of lymphocytes isolated from mice or monkeys previously immunized with various DENV antigens to in vitro stimulation with DENVs. A positive proliferative response was obtained with lymphocytes of animals immunized with either live DENV-2 or its recombinant proteins. A similar result was also obtained with CD8+ T cells from mice immunized with live DENV-1 or DENV-2 following stimulation with homologous viruses. A comparison of the carboxyfluorescein diacetate succinimidyl ester (CFSE)-based and a 3H-thymidine incorporation-based assays of proliferative response of total lymphocytes showed a fair correlation of results of both assays. However, the CSFE-based assay offers in addition the determination of contribution of the CD8+ or other subsets of T cells to total proliferative response. These results represent the first and successful application of a CFSE-based assay to the evaluation of cell-mediated immunity to DENVs. This assay might be also exploited in testing candidate DENV vaccines.

Germination behavior, biochemical features and sequence analysis of the RACK1/arcA homolog from Phaseolus vulgaris

Partial peptide sequence of a 36 kDa protein from common bean embryo axes showed 100% identity with a reported beta-subunit of a heterotrimeric G protein from soybean. Analysis of the full sequence showed 96.6% identity with the reported soybean G(beta)-subunit, 86% with RACK1B and C from Arabidopsis and 66% with human and mouse RACK1, at the amino acid level. In addition, it showed 85.5, 85 and 83% identities with arcA from Solanum lycopersicum, Arabidopsis (RACK1A) and Nicotiana tabacum, respectively. The amino acid sequence displayed seven WD40 domains and two sites for activated protein kinase C binding. The protein showed a constant expression level but the mRNA had a maximum at 32 h post-imbibition. Western immunoblotting showed the protein in vegetative plant tissues, and in both microsomal and soluble fractions from embryo axes. Synthetic auxin treatment during germination delayed the peak of RACK1 mRNA expression to 48 h but did not affect the protein expression level while the polar auxin transport inhibitor, naphtylphtalamic acid had no effect on either mRNA or protein expression levels. Southern blot and genomic DNA amplification revealed a small gene family with at least one member without introns in the genome. Thus, the RACK1/arcA homolog from common bean has the following features: (1) it is highly conserved; (2) it is both soluble and insoluble within the embryo axis; (3) it is encoded by a small gene family; (4) its mRNA has a peak of expression at the time point of germination stop and (5) its expression is only slightly affected by auxin but unaffected by an auxin transport blocker.

[Current treatment of pediatric penetrating traumas]

INTRODUCTION

The traditional management of pediatric penetrating trauma has been wide surgical examination. However, the selective nonoperative management is increasing thanks to the precise diagnosis obtained from radiologic studies as CT scan. The purpose of this study is reviewing our experience in the last eight years with a less invasive management.

PATIENTS AND METHODS

We retrospectively reviewed (2000-2007) the patients with penetrating injuries of different parts of the body (excluding cranioencephalic traumatism) treated in our center and registered by the Clinical Documentation Unit. The variables collected and evaluated included age, mechanism of injury, kind of injury, diagnostic and therapeutic modalities and outcome.

RESULTS

There were 17 patients (median 9.5 years, range 4-17) with penetrating trauma. According the localization of injury the patients were divided into 4 groups: abdominal (17.6%), thoracic (23.5%), cervical (17.6%) and extremities (41.2%). The most frequent kind of injuries were: skin and muscle (with or without penetrating peritoneal or chest cavity, 52.9%) vascular or neurological structures (29.4%). We would like to highlight one case of cardiac perforation and taponade, one traqueal lesion and one case of external iliac vein injury. The injuries caused by glass (35.3%) and sharp arms (29,4%) were the most frequent mechanism. Simple suture and observation was treatment enough in 47.1%. Three patients required neural and vascular micro suture. One patient followed a thoracotomy procedure and other one, a sternotomy. It wasn't necessary any laparotomy. No patient died and 88% of the patients have no sequelae.

CONCLUSIONS

Most of the penetrating child traumas have good prognosis and are associated with few sequelae. Low energy thoracic and abdominal penetrating traumas can be managed conservatively when the patient is hemodiynamically stable and CT scan shows no organ injury, avoiding unnecessary surgical examinations.

[Five years of renal trauma in a paediatric trauma center: new tools in the diagnostic and therapeutic process]

INTRODUCTION

There is general agreement in the conservative management of most renal traumas, but questions like the role of angiography are still controversial. Our objective is to review the paediatric renal trauma characteristics, propose a therapeutic protocol and suggest new therapeutic tools.

MATERIAL AND METHODS

Retrospective review of clinical records (epidemiology, diagnostic methods, renal injury grade according to the AAST Organ Injury Scale, treatment and follow up) of the paediatric renal injuries at Vail d'Hebron Hospital in the last 5 years. Outline of a diagnostic-therapeutic protocol consistent with the literature.

RESULTS

Since 2001, 18 cases of paediatric renal trauma have been diagnosed. Median of age was 10 years (range 2-17). Renal injury grade was: I (4), II (5), III (4), IV (4), V (1). Main mechanisms of injury were car and motorcicle accidents (4), fall (3), bicycle (3) and sports (3). There were different severity associated injuries in 10 patients. Abdominal exploration was normal in 6 cases, and in 5 (including the grade V injury) hematuria was absent or was microscopic. Mean hematocrit and hemoglobine were 34.5% y 11.8 g/dl. Abdominal CT was performed in all cases, detecting injuries that were unnoticed with ultrasound exploration. Complications were: renal artery pseudoaneurism (1), urinoma (1), uretero-pelvic joint disruption (1), arterial hypertension (3), renal colic (1). Management was: conservative in 13 cases, angiography in 4 (2 embolizations of bleeding vessels, 1 pseudoaneurism embolization, 1 placement of endovascular stents in an injury of the arterial intima), delayed surgery in 2 (1 nefrectomy, 1 uretero-pyeloplasty). All of them received prophylactic antibiotics; 10 had self-limited fever with negative cultures. Only in 2 cases DMSA at 6 months was inferior to 20%. There were no deaths.

CONCLUSIONS

In paediatric patients, there can be severe renal injuries despite absence of hematuria and a normal physical exam and hemogram. Abdominal CT with endovenous contrast is the keystone of diagnosis, and identifies vascular injuries that might need immediate treatment, like renal ischemia. Angiography is an important tool to consider in case of persistent bleeding or renal infarctation.

Fast, efficient and reproducible genetic transformation of Phaseolus spp. by Agrobacterium rhizogenes

This transformation procedure generates, with high efficiency (70-90%), hairy roots in cultivars, landraces and accessions of Phaseolus vulgaris (common bean) and other Phaseolus spp. Hairy roots rapidly develop after wounding young plantlets with Agrobacterium rhizogenes, at the cotyledon node, and keeping the plants in high-humidity conditions. Callogenesis always precedes hairy-root formation, and after 15 days, when roots develop at wounded sites, the stem with the normal root is cleaved below the hairy root zone. Transgenic roots and nodules co-transformed with a binary vector can be easily identified using a reporter gene. This procedure, in addition to inducing robust transgenic hairy roots that are susceptible to being nodulated by rhizobia and to fixing nitrogen efficiently, sets the foundation for a high-throughput functional genomics approach on the study of root biology and root-microbe interactions. This protocol can be completed within 30 days.

Agrobacterium rhizogenes transformation of the Phaseolus spp.: a tool for functional genomics

A fast, reproducible, and efficient transformation procedure employing Agrobacterium rhizogenes was developed for Phaseolus vulgaris L. wild accessions, landraces, and cultivars and for three other species belonging to the genus Phaseolus: P. coccineus, P. lunatus, and P. acutifolius. Induced hairy roots are robust and grow quickly. The transformation frequency is between 75 and 90% based on the 35-S promoter-driven green fluorescent protein and beta-glucuronidase expression reporter constructs. When inoculated with Rhizobium tropici, transgenic roots induce normal determinate nodules that fix nitrogen as efficiently as inoculated standard roots. The A. rhizogenes-induced hairy root transformation in the genus Phaseolus sets the foundation for functional genomics programs focused on root physiology, root metabolism, and root-microbe interactions.

Profilin tyrosine phosphorylation in poly-L-proline-binding regions inhibits binding to phosphoinositide 3-kinase in Phaseolus vulgaris

The profilin family consists of a group of ubiquitous highly conserved 12-15 kDa eukaryotic proteins that bind actin, phosphoinositides, poly-l-proline (PLP) and proteins with proline-rich motifs. Some proteins with proline-rich motifs form complexes that have been implicated in the dynamics of the actin cytoskeleton and processes such as vesicular trafficking. A major unanswered question in the field is how profilin achieves the required specificity to bind such an array of proteins. It is now becoming clear that profilin isoforms are subject to differential regulation and that they may play distinct roles within the cell. Considerable evidence suggests that these isoforms have different functional roles in the sorting of diverse proteins with proline-rich motifs. All profilins contain highly conserved aromatic residues involved in PLP binding which are presumably implicated in the interaction with proline-rich motif proteins. We have previously shown that profilin is phosphorylated on tyrosine residues. Here, we show that profilin can bind directly to Phaseolus vulgaris phosphoinositide 3-kinase (PI3K) type III. We demonstrate that a new region around Y72 of profilin, as well as the N- and C-terminal PLP-binding domain, recognizes and binds PLP and PI3K. In vitro binding assays indicate that PI3K type III forms a complex with profilin in a manner that depends on the tyrosine phosphorylation status within the proline-rich-binding domain in profilin. Profilin-PI3K type III interaction suggests that profilin may be involved in membrane trafficking and in linking the endocytic pathway with actin reorganization dynamics.

[Hirschsprung-neurointestinal dyspasia: diferential diagnosis and reliability of diagnostic procedures]

The suspicion of Hirschsprung's disease (HD) or Neurointestinal Dysplasia (NID) arises with the appearance of a common symtomatology : delay in meconium evacuation, abdominal distention, vomiting, intestinal occlusion and ultimately, chronic constipation. The need to perform a correct differential diagnosis between both pathologies is essential, given that the treatment of HD is surgical while NID is expectant. The objective of this paper is to define the necessity of using or not all the diagnostic tests simultaneously to obtain a precise diagnosis. The authors performed a complete clinical review of a series of 42 HD and 18 NID analysing the results of diagnostic procedures (Radiology / transition zone, anorrectal manometry / absence of anal inhibitory reflex, and suction biopsy / AcHE study). The authors concluded that is necessary to perform all the three diagnostic procedures simultaneously in all patients with symtomatology given that not one test has the capacity to provide a diagnosis alone. Anorectal manometry has proven to be the most reliable test to diagnose HD. The authors agree with the guidelines published by Meier Ruge in 2004 to diagnose NID.

Development of a nasal vaccine for chronic hepatitis B infection that uses the ability of hepatitis B core antigen to stimulate a strong Th1 response against hepatitis B surface antigen

There are estimated to be 350 million chronic carriers of hepatitis B infection worldwide. Patients with chronic hepatitis B are at risk of liver cirrhosis with associated mortality because of hepatocellular carcinoma and other complications. An important goal, therefore, is the development of an effective therapeutic vaccine against chronic hepatitis B virus (HBV). A major barrier to the development of such a vaccine is the impaired immune response to HBV antigens observed in the T cells of affected patients. One strategy to overcome these barriers is to activate mucosal T cells through the use of nasal vaccination because this may overcome the systemic immune downregulation that results from HBV infection. In addition, it may be beneficial to present additional HBV epitopes beyond those contained in the traditional hepatitis B surface antigen (HbsAg) vaccine, for example, by using the hepatitis B core antigen (HBcAg). This is advantageous because HBcAg has a unique ability to act as a potent Th1 adjuvant to HbsAg, while also serving as an immunogenic target. In this study we describe the effect of coadministration of HBsAg and HBcAg as part of a strategy to develop a more potent and effective HBV therapeutic vaccine.

Immunological characterization of two hepatitis B core antigen variants and their immunoenhancing effect on co-delivered hepatitis B surface antigen

The hepatitis B virus (HBV) core and surface antigens are potent immunogens in animal models and humans. They have been used in vaccine studies for prevention or therapy of HBV diseases and also as carrier molecules in new developments. In this study we explored the nasal immunogenicity of two different variants of the recombinant complete nucleocapsid (HBcAg) as well as their adjuvant effect on hepatitis B surface antigen (HBsAg). To characterize the immune response, the serum IgG antibody response was tested during one year against both antigens, and the serum and vaginal secretions were tested for recognition of linear epitopes of HBcAg for both HBcAg variants. The results obtained evidenced that the intranasal immunogenicity of both HBcAg variants was similar and high, developing early and long lasting IgG responses. A similar recognition pattern to all sera and vaginal washes samples was generated by the two variants of HBcAg, also similar to a pool of human anti-HBcAg positive sera. A synergistic effect in the enhancement of the immunogenicity for both antigens was evidenced in the combined formulation after nasal administration. Taken together, these results would be of interest in the design of more potent therapeutic and preventive vaccines complementing systemic and mucosal responses.

Memory immune response generated inCercopithecus aethiopsagainst meningococcal polysaccharide serogroup C conjugate vaccine

The chemical conjugation of bacterial polysaccharide to carrier proteins has proved to be an efficient tool to improve the immunological response against these bacterial antigens. In this study, we characterized the antibody response generated in a non-human primate model against the meningococcal capsular polysaccharide serogroup C (CCPS) conjugated to the P64k protein. Similar to licensed vaccines the CCPS conjugate is able to generate a good memory immune response with antibody titers threefold higher than the free CCPS. Three different ELISA protocols were used to measure the antibody response and the importance of the coating antigen was demonstrated. The ELISA using the derivatized CCPS showed the best results and had a high correlation with the bactericidal activity. The antibodies elicited showed a high protective capacity when assayed in the infant rat protection model.

Discriminative capacity of calcaneal quantitative ultrasound and of osteoporosis and fracture risk factors in postmenopausal women with osteoporotic fractures

Bone fragility fractures constitute the principal complication of osteoporosis. The identification of individuals at high risk of sustaining osteoporotic fractures is important for implementing preventive measures. The purpose of this study is to analyze the discriminative capacity of a series of osteoporosis and fracture risk factors, and of calcaneal quantitative ultrasound (QUS), in a population of postmenopausal women with a history of osteoporotic fracture. A cross-sectional analysis was made of a cohort of 5195 women aged 65 or older (mean +/- SD: 72.3 +/- 5.4 years) seen in 58 primary care centers in Spain. A total of 1042 women (20.1%) presented with a history of osteoporotic fracture. Most fractures (93%) were non-vertebral. Age-adjusted odds ratios corresponding to each decrease in one standard deviation of the different QUS parameters ranged from 1.47 to 1.55 (P < 0.001) for fractures. The age-adjusted multivariate analysis yielded the following risk factors independently associated with a history of osteoporotic fracture: number of fertile years, a family history of fracture, falls in the previous year, a history of chronic obstructive airway disease, the use of antiarrhythmic drugs, and a low value for any of the QUS parameters. The area under the receiver operating characteristic curve of the best model was 0.656. In summary, a series of easily assessable osteoporotic fracture risk factors has been identified. QUS was shown to discriminate between women with and without a history of fracture, and constitutes a useful tool for assessing fracture risk. Various of the vertebral and hip fracture risk factors frequently cited in North American and British populations showed no discriminative capacity in our series--thus suggesting that such factors may not be fully applicable to our population and/or to the predominant type of fractures included in the present study.

Carboxy-terminally truncated Dengue 4 virus envelope glycoprotein expressed in Pichia pastoris induced neutralizing antibodies and resistance to Dengue 4 virus challenge in mice

We have expressed a recombinant Dengue 4 virus envelope glycoprotein (E4rec), truncated at its C-terminus by 53 amino acids, in Pichia pastoris. The presence of E4rec was confirmed by Western-blot using anti-DEN 4 hyper immune mouse ascitic fluid. E4rec migrated during SDS-PAGE as a 64 kDa protein. Treatment with endoglycosidases showed that the E protein was modified by the addition of short mannose chains and the absence of hyperglycosylation. When administered to BALB-C mice, E4rec elicited a DEN 4 neutralizing antibody response haemagglutination inhibition antibodies and specific memory T cell response. Mice immunized were also significantly protected against lethal DEN 4 virus challenge (86.6%, p < 0.001).

A recombinant envelope protein from Dengue virus purified by IMAC is bioequivalent with its immune-affinity chromatography purified counterpart

Semi-purified DEN-4 envelope protein, obtained in Pichia pastoris, was capable of generating neutralising and protecting antibodies after immunisation in mice. Here we compared two purification processes of this recombinant protein using two chromatographic steps: immune-affinity chromatography and immobilised metal ion adsorption chromatography (IMAC). The protein purified by both methods produced functional antibodies reflected by titres of haemagglutination inhibition and neutralisation. IMAC could be used as an alternative for high scale purification.

Safety and preliminary immunogenicity of the recombinant outer membrane protein P64k of Neisseria meningitidis in human volunteers

P64k is a meningococcal protein from Neisseria meningitidis that has been obtained by recombinant DNA technology. Recombinant P64k has been extensively characterized by physicochemical and immunological methods. Lately this protein has been found to act as a versatile immunological carrier for weak antigens in mice. In the present work, a Phase I clinical trial was carried out in healthy volunteers who received three inoculations of either placebo or recombinant P64k (20 or 50 microg). No severe adverse events occurred during the trial. Only mild adverse events in ten volunteers were observed. At 1 month after the third dose, 15 out of 18 volunteers (83.3%) who received the recombinant antigen had a P64k-specific antibody titre > or =1:100, as detected by ELISA. A fourth dose, given 9 months after the third one, elicited a potent booster immune response in P64k vaccinees. Accordingly, these P64k formulations were considered safe and immunogenic in healthy human volunteers.

Immunogenicity of recombinant class 1 protein from Neisseria meningitidis refolded into phospholipid vesicles and detergent

The possibility of eliciting bactericidal antibodies against a recombinant class 1 protein (P1) from Neisseria meningitidis, joined to the first 45 amino acids of the neisserial LpdA protein (PM82), was examined. P1 was produced in Escherichia coli as intracellular inclusion bodies, from which it was purified and reconstituted by (a) inclusion into phospholipid vesicles and detergent and (b) refolding in 0.1% SDS. When Balb/c mice were immunised, high titres of subtype-specific bactericidal antibodies against P1 were obtained in both cases. These results suggest that in spite of being a denaturing agent, it is possible to use SDS to reconstitute the P1 protein in a conformation that exposes the immunodominat regions.

Biochemical characterization of profilin from seeds of Phaseolus vulgaris L

The isoform composition of the 14.4 kDa profilin polypeptide was analyzed in seeds, leaves, flowers, roots and root-nodules from Phaseolus vulgaris L. Isoforms of pIs approximately 4.4-5 were present in all the tissues analyzed. The biochemical features of the protein present in seed tissue were determined. Seed profilin bound to Phenyl-Sepharose under low salt conditions which suggested a hydrophobic interaction; however, it was not associated with microsomal membranes nor it partitioned as a hydrophobic protein in Triton X-114. Fractions eluting from poly-L-proline or Phenyl-Sepharose columns contained well detectable amounts of profilin but no actin, suggesting that most of the protein was not present as profilactin in the seed. However, seed profilin appeared to be in some kind of complex since several molecular weight species were observed on native gels. In addition, profilin was found preferentially in the embryo axis and light microscopic immunolocalization showed a cytoplasmic distribution in this tissue.

P64k meningococcal protein as immunological carrier for weak immunogens

Previously, the P64k meningococcal protein, an antigen of 64 kDa expressed in Escherichia coli, has been extensively characterized. We have successfully conjugated several synthetic peptides and meningococcal group C polysaccharide to P64k. In three out of four model peptides, the murine humoral immune response against the homologous peptide, evaluated after three doses of conjugate, was higher in the animals immunized with the coupled peptide than in those that received free peptide. The fourth and largest was immunogenic by itself. Similarly, the antigroup C polysaccharide levels reached by conjugated polysaccharide were significantly higher than those produced against unconjugated polysaccharide. As a carrier for one of the peptides, P64k was compared with bovine serum albumin (BSA) and tetanus toxoid (TT), being able to induce slightly higher or similar antipeptide antibody levels than these well-establish protein carriers. Our results suggest that recombinant P64k protein could be a readily available immunological carrier, as efficient as other commonly used large carrier molecules.

Profilin in Phaseolus vulgaris is encoded by two genes (only one expressed in root nodules) but multiple isoforms are generated in vivo by phosphorylation on tyrosine residues

Actin-binding proteins such as profilins participate in the restructuration of the actin cytoskeleton in plant cells. Profilins are ubiquitous actin-, polyproline-, and inositol phospholipid-binding proteins, which in plants are encoded by multigene families. By 2D-PAGE and immunoblotting, we detected as much as five profilin isoforms in crude extracts from nodules of Phaseolus vulgaris. However, by immunoprecipitation and gel electrophoresis of in vitro translation products from nodule RNA, only the most basic isoform of those found in nodule extracts, was detected. Furthermore, a bean profilin cDNA probe hybridised to genomic DNA digested with different restriction enzymes, showed either a single or two bands. These data indicate that profilin in P. vulgaris is encoded by only two genes. In root nodules only one gene is expressed, and a single profilin transcript gives rise to multiple profilin isoforms by post-translational modifications of the protein. By in vivo 32P-labelling and immunoprecipitation with both, antiprofilin and antiphosphotyrosine-specific antibodies, we found that profilin is phosphorylated on tyrosine residues. Since chemical (TLC) and immunological analyses, as well as plant tyrosine phosphatase (AtPTP1) treatments of profilin indicated that tyrosine residues were phosphorylated, we concluded that tyrosine kinases must exist in plants. This finding will focus research on tyrosine kinases/tyrosine phosphatases that could participate in novel regulatory functions/pathways, involving not only this multifunctional cytoskeletal protein, but other plant proteins.

Characterisation of the lpdA gene from Neisseria meningitidis by polymerase chain reaction, restriction fragment length polymorphism and sequencing

P64k protein from Neisseria meningitidis is well recognised in sera from individuals convalescent from meningococcal disease or vaccinated with the Cuban antimeningococcal vaccine VA-MENGOC-BC. The presence of the protein in more than 80 meningococcal strains has also been verified. It is immunogenic in animal models and the antibodies elicited show bactericidal activity against meningococci. To further investigate at the molecular level whether lpdA, the gene coding for P64k protein, is conserved among different N. meningitidis strains, a total of 20 strains isolated from different geographic areas were differentiated on the basis of restriction fragment length polymorphism (RFLP) patterns after polymerase chain reaction (PCR) amplification of the lpdA gene and restriction endonuclease digestion with HpaII. Although a total of five different PCR-RFLP patterns were present, nucleotide sequence determination showed that identity levels were as high as 93-99% among the N. meningitidis strains analysed.

Expression in Escherichia coli of the lpdA gene, protein sequence analysis and immunological characterization of the P64k protein from Neisseria meningitidis

By making use of recombinant DNA technology it is possible to characterize meningococcal outer membrane proteins (OMPs) capable of stimulating a host immune response. The lpdA gene, which codes for an OMP (P64k) from Neisseria meningitidis, was cloned in Escherichia coli. The recombinant protein was recognized by sera from patients convalescing from meningococcal disease. The monoclonal antibodies obtained against the recombinant protein recognized the natural protein on a Western blot, and monoclonal antibody 114 was assayed in ELISA with a panel of 85 N. meningitidis strains. The protein was recognized in 81 strains (95.3%); the strains that were not recognized were neither epidemic nor isolated from systemic disease. The complete amino acid sequence of P64k was obtained by automatic sequencing and MS.

A novel cancer vaccine composed of human-recombinant epidermal growth factor linked to a carrier protein: report of a pilot clinical trial

BACKGROUND

There is evidence of a relationship between epidermal growth factor (EGF) and tumor cell proliferation, such as the overexpression of EGF receptor (EGF-R) in different human tumors, which makes this system an interesting target for cancer treatment. Up to now, passive immunotherapy with monoclonal antibodies against the EGF-R has been assayed in clinics. Our approach consists of active immunotherapy with human EGF (hu-EGF). We conducted a pilot clinical trial to define the safety, toxicity and immunogenicity of vaccination with hu-EGF coupled to a carrier protein.

PATIENTS AND METHODS

Ten patients with histologically-proven malignant carcinomas (colon, lung, stomach and prostate) in advanced clinical stages were enrolled. Patients were immunized twice (on days 0 and 15) with hu-EGF linked to either tetanic toxoid (TT, five patients) or P64K Neisseria Meningitidis recombinant protein (P64k, five patients), intradermically, using aluminium hydroxyde as adjuvant.

RESULTS

In both groups 60% of patients developed anti-EGF antibody titers without evidence of toxicity. Secondary reactions were very mild, limited to erythema and itching at the site of injection, which disappeared without medication.

CONCLUSIONS

We conclude that the proposed vaccination with hu-EGF was well tolerated and that antibody titers against self EGF were developed. The results of this trial may be useful in the design of new clinical trials with higher dose immunization protocols and using more effective adjuvants.

Sequence analysis of the structural tbpA gene: protein topology and variable regions within neisserial receptors for transferrin iron acquisition

The gene coding for the 98-kDa meningococcal outer membrane transferrin binding protein 1 (TbpA) from strain B385 was cloned and sequenced. Sequence comparison among its deduced aminoacid sequence and those from TbpA and the closely related LbpA (lactoferrin binding protein) gene from three different meningococcal strains, and four isolates from two other bacterial pathogens, showed that TbpA variability is confined to five specific segments, designated VR1 (199-287), VR2 (306-381), VR3 (480-546), VR4 (618-651) and VR5 (681-708). The third VR was the most variable among strains both at the nucleotide and amino acid levels. Six additional tbpA genes from different meningococcal strains were cloned and its VR3 sequence determined. On the basis of this data we were able to cluster tbpA genes in two groups: D (bearing a deletion in VR3) and N (nondeleted); all N and D strains belonging to the groups of high or low molecular weight transferrin receptor isotype, respectively. However, by phenogram analysis, the prototypical strain M982 (Group II) was clustered with M990 (B16B6 isotype, Group I). These results point to the existence of important exposed regions as well as to the possibility of horizontal gene exchange involving this locus. A topology model with 14 exposed loops and 28 membrane spanning segments was postulated. According to this tentative analysis, TbpA as well as LbpA proteins should form a gated channel in the neisserial outer membrane. The variable regions were located in the fifth, sixth, eighth, 10th and 11th loops respectively. Among TbpAs VR1, VR2, and VR3 resulted the most relevant regions.