Energy spectrum of cosmic-ray electrons at TeV energies

The very large collection area of ground-based gamma-ray telescopes gives them a substantial advantage over balloon or satellite based instruments in the detection of very-high-energy (>600 GeV) cosmic-ray electrons. Here we present the electron spectrum derived from data taken with the High Energy Stereoscopic System (H.E.S.S.) of imaging atmospheric Cherenkov telescopes. In this measurement, the first of this type, we are able to extend the measurement of the electron spectrum beyond the range accessible to direct measurements. We find evidence for a substantial steepening in the energy spectrum above 600 GeV compared to lower energies.

Limits on an energy dependence of the speed of light from a flare of the active galaxy PKS 2155-304

In the past few decades, several models have predicted an energy dependence of the speed of light in the context of quantum gravity. For cosmological sources such as active galaxies, this minuscule effect can add up to measurable photon-energy dependent time lags. In this Letter a search for such time lags during the High Energy Stereoscopic System observations of the exceptional very high energy flare of the active galaxy PKS 2155-304 on 28 July 2006 is presented. Since no significant time lag is found, lower limits on the energy scale of speed of light modifications are derived.

Complications of three sacrospinous ligament fixation techniques

OBJECTIVES

To compare the complications of three techniques used to pass the suture through the sacrospinous ligament when performing sacrospinous ligament fixation (SSLF): (1) the standard needle driver with direct visualization; (2) the Deschamps ligature carrier by palpation; and (3) the Miya hook ligature carrier by palpation.

MATERIALS AND METHODS

A retrospective chart review of 240 patients undergoing SSLF was performed. A standard needle driver with direct visualization was used for 46 patients; the Deschamps ligature carrier was used for 173, and the Miya hook for 21 patients. Intraoperative and postoperative complications were compared between the groups.

RESULTS

Twelve women (5%) had intraoperative and forty women (17%) had postoperative complications suspected directly from the suture placement. There was no statistically significant difference in the rate of total intraoperative complications among the three groups. The proportion of patients with postoperative complications that were felt to be directly related to the suture passage technique was significantly higher in the Deschamps group compared to the direct visualization group (18% vs 2%, P=0.002).

CONCLUSION

Passing the suture through the sacrospinous ligament under direct visualization may result in less intra and postoperative complications.

Determination of priority organic micro-pollutants in water by gas chromatography coupled to triple quadrupole mass spectrometry

A multiclass method has been developed for screening, quantification and confirmation of organic micro-pollutants in water by gas chromatography coupled to mass spectrometry with a triple quadrupole analyzer. The work has been focused on the determination of more than 50 compounds belonging to different chemical families: 19 organochlorine and organophosphorus insecticides, 6 herbicides, 7 polychlorinated biphenyls, 16 polycyclic aromatics hydrocarbons, 2 brominated diphenyl ethers, and 3 octyl/nonyl phenols and pentachlorobenzene. Most of these analytes are included in the list of priority substances in the framework on European Water Policy. Analyte extraction was performed by solid phase extraction using C18 cartridges, and five isotopically labeled standards were added before extraction as surrogates. Analyses were performed by gas chromatography with tandem mass spectrometry (MS/MS) in electron impact mode. Accuracy and precision were evaluated by means of recovery experiments using water samples fortified at two concentration levels (25 and 250 ng L(-1)), with satisfactory results for most of analytes. The excellent selectivity and sensitivity reached in selected reaction monitoring mode allowed us satisfactory quantification and confirmation at levels as low as 25 ng L(-1). Two MS/MS transitions were acquired for each analyte, using the Q/q intensity ratio as a confirmatory parameter. The method developed was applied to the analysis of surface, ground and wastewater samples collected from the Valencia Region (Spain). Analytical methodology using negative chemical ionization mode was also validated for the organochlorine compounds selected, showing a superior sensitivity and lower detection limits.

Identification and characterization of a nodH ortholog from the alfalfa-nodulating Or191-like rhizobia

Nodulation of Medicago sativa (alfalfa) is known to be restricted to Sinorhizobium meliloti and a few other rhizobia that include the poorly characterized isolates related to Rhizobium sp. strain Or191. Distinctive features of the symbiosis between alfalfa and S. meliloti are the marked specificity from the plant to the bacteria and the strict requirement for the presence of sulfated lipochitooligosaccharides (Nod factors [NFs]) at its reducing end. Here, we present evidence of the presence of a functional nodH-encoded NF sulfotransferase in the Or191-like rhizobia. The nodH gene, present in single copy, maps to a high molecular weight megaplasmid. As in S. meliloti, a nodF homolog was identified immediately upstream of nodH that was transcribed in the opposite direction (local synteny). This novel nodH ortholog was cloned and shown to restore both NF sulfation and the Nif+Fix+ phenotypes when introduced into an S. meliloti nodH mutant. Unexpectedly, however, nodH disruption in the Or191-like bacteria did not abolish their ability to nodulate alfalfa, resulting instead in a severely delayed nodulation. In agreement with evidence from other authors, the nodH sequence analysis strongly supports the idea that the Or191-like rhizobia most likely represent a genetic mosaic resulting from the horizontal transfer of symbiotic genes from a sinorhizobial megaplasmid to a not yet clearly identified ancestor.

Nanoparticles: pharmacological and toxicological significance

Nanoparticles are tiny materials (<1000 nm in size) that have specific physicochemical properties different to bulk materials of the same composition and such properties make them very attractive for commercial and medical development. However, nanoparticles can act on living cells at the nanolevel resulting not only in biologically desirable, but also in undesirable effects. In contrast to many efforts aimed at exploiting desirable properties of nanoparticles for medicine, there are limited attempts to evaluate potentially undesirable effects of these particles when administered intentionally for medical purposes. Therefore, there is a pressing need for careful consideration of benefits and side effects of the use of nanoparticles in medicine. This review article aims at providing a balanced update of these exciting pharmacological and potentially toxicological developments. The classes of nanoparticles, the current status of nanoparticle use in pharmacology and therapeutics, the demonstrated and potential toxicity of nanoparticles will be discussed.

Senescence-associated genes induced during compatible viral interactions with grapevine and Arabidopsis

The senescence process is the last stage in leaf development and is characterized by dramatic changes in cellular metabolism and the degeneration of cellular structures. Several reports of senescence-associated genes (SAGs) have appeared, and an overlap in some of the genes induced during senescence and pathogen infections has been observed. For example, the enhanced expression of SAGs in response to diseases caused by fungi, bacteria, and viruses that trigger the hypersensitive response (HR) or during infections induced by virulent fungi and bacteria that elicit necrotic symptoms has been observed. The present work broadens the search for SAGs induced during compatible viral interactions with both the model plant Arabidopsis thaliana and a commercially important grapevine cultivar. The transcript profiles of Arabidopsis ecotype Uk-4 infected with tobacco mosaic virus strain Cg (TMV-Cg) and Vitis vinifera cv. Carménère infected with grapevine leafroll-associated virus strain 3 (GLRaV-3) were analysed using microarray slides of the reference species Arabidopsis. A large number of SAGs exhibited altered expression during these two compatible interactions. Among the SAGs were genes that encode proteins such as proteases, lipases, proteins involved in the mobilization of nutrients and minerals, transporters, transcription factors, proteins related to translation and antioxidant enzymes, among others. Thus, part of the plant's response to virus infection appears to be the activation of the senescence programme. Finally, it was demonstrated that several virus-induced genes are also expressed at elevated levels during natural senescence in healthy plants.

Gene expression associated with compatible viral diseases in grapevine cultivars

Viral diseases affect grapevine cultures without inducing any resistance response. Thus, these plants develop systemic diseases and are chronically infected. Molecular events associated with viral compatible infections responsible for disease establishment and symptoms development are poorly understood. In this study, we surveyed viral infection in grapevines at a transcriptional level. Gene expression in the Vitis vinifera red wine cultivars Carménère and Cabernet-Sauvignon naturally infected with GLRaV-3 were evaluated using a genome-wide expression profiling with the Vitis vinifera GeneChip from Affymetrix. We describe numerous genes that are induced or repressed in viral infected grapevines leaves. Changes in gene expression involved a wide spectrum of biological functions, including processes of translation and protein targeting, metabolism, transport, and cell defense. Considering cellular localization, the membrane and endomembrane systems appeared with the highest number of induced genes, while chloroplastic genes were mostly repressed. As most induced genes associated with the membranous system are involved in transport, the possible effect of virus in this process is discussed. Responses of both cultivars are analyzed and the results are compared with published data from other species. This is the first study of global gene profiling in grapevine in response to viral infections using DNA microarray.

Selective inhibition of phosphodiesterase-4 ameliorates chronic colitis and prevents intestinal fibrosis

The phosphodiesterase-4 (PDE4) inhibitors may be an important target in the treatment of several inflammatory conditions. The anti-inflammatory effect of PDE4 inhibitors bears similarities with that of steroids, without interfering with the hypophysary-adrenal-axis. We compared the effect of rolipram, a selective PDE4 inhibitor, with steroids on the clinical course of experimental colitis induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS). Three groups of rats (n = 20) received TNBS. One group received methylprednisolone from day 7, another group received rolipram from the same day, and control group received no further treatment. On days 14 and 21 after TNBS instillation, sets of 10 rats underwent colonic dialysis to measure eicosanoid release. Colonic lesions were blindly scored, and colons were homogenized for quantification of myeloperoxidase (MPO) activity and collagen content. Concentration of tumor necrosis factor alpha (TNF-alpha) and transforming growth factor beta1 (TGF-beta1) in colonic tissue was also measured. Both treatments reduced significantly the eicosanoid release and MPO activity. On day 14, both rolipram and methylprednisolone significantly reduced TNF-alpha content, but TGF-beta1 was only inhibited by rolipram. On day 21, lesion scores and collagen content were significantly reduced only in rolipram-treated group. In conclusion, PDE4 inhibition by rolipram markedly ameliorates the course of chronic colitis and it is superior to methylprednisolone in preventing late collagen deposition.

[Hypovolemic shock during surgery caused by a rectus sheath hematoma]

Prophylactic treatment with low molecular weight heparins (LMWH) is currently widely used to prevent thromboembolic events. However, such treatment is not free of risk. Among the possible complications described is rectus sheath hematoma. We report the case of a patient undergoing surgery for a hypophysial adenoma approached by the transsphenoidal route. He received LMWH prophylaxis for thromboembolism and showed a tendency to hypotension during surgery. The patient's condition deteriorated to hypovolemic shock accompanied by episodes of atrial fibrillation with rapid ventricular response. With the transfusion of medications, blood products and plasma volume expanders, the patient was stabilized and surgery was completed. A computed tomography scan then revealed a hematoma occupying the greater part of the left anterior rectus muscle. With conservative wait-and-see treatment the abdominal symptoms disappeared and the hematoma gradually receded until fully resolved. Spontaneous rectus sheath hematoma is a rare condition. Presentation is quite nonspecific and computed tomography is needed for reaching a firm diagnosis. When a hematoma is large, the initial clinical picture may include hypovolemic shock, which may develop during surgery if the hematoma is not diagnosed early. Intraoperative management will be much more difficult than it would have been if diagnosis and treatment had taken place before the operation.

Avoiding Free Nipple Grafts During Reduction Mammaplasty in Patients With Gigantomastia

Excessive breast hypertrophy or gigantomastia (>2000 g excision of tissue per breast) has traditionally been approached with breast amputation and free nipple grafting during reduction mammaplasty procedures. Disadvantages of free nipple grafts include loss of sensation, poor projection, uneven nipple-areolar complex pigmentation, and loss of lactation. We report our experiences utilizing the inferior pedicle technique of reduction mammaplasty with successful preservation of the nipple-areola complex for patients with gigantomastia. Between 2001 and 2003, 15 patients (ages 19--45) were identified with gigantomastia through review of pathology and operative reports. The inferior pedicle technique was performed in all cases by the attending staff assisted by plastic surgery residents. Patients were followed regularly from 1 week up to 1 year postoperatively. All patients reported relief from the physical sequelae of breast hypertrophy. One patient experienced bilateral partial nipple desquamation; she maintained sensation throughout and healed well with moist dressings. Otherwise, there were no complications and all patients achieved satisfactory esthetic outcomes. Our results suggest that inferior pedicle technique can be successfully performed in patients with gigantomastia. Breast amputation with free nipple grafting need not be considered standard practice for this patient population. Maintaining a wider pedicle base and meticulous intraoperative handling of the pedicle may contribute to the increased viability of the nipple-areolar complex during these cases.

Impairment of health-related quality of life in patients with inflammatory bowel disease: a Spanish multicenter study

BACKGROUND

Inflammatory bowel disease impairs patients' perception of health and has a negative impact on health-related quality of life (HRQOL). Most studies include patients from a single hospital. This may bias limit results through the use of small patient samples and/or samples within a restricted disease spectrum.

METHODS

HRQOL was measured in patients with ulcerative colitis (UC) and Crohn's disease (CD) from 9 hospitals located in different geographical areas in Spain using 2 questionnaires: the Spanish version of the Inflammatory Bowel Disease Questionnaire (IBDQ) and the EuroQol. Results are expressed as medians.

RESULTS

The study included 1156 patients (528 patients with UC and 628 with CD; median age, 35 yr; slight predominance of women, 617 versus 539). HRQOL worsened in parallel with disease severity to a similar extent in both UC (IBDQ scores of 6.1, 4.7, and 4.0 for the 3 disease severity groups, respectively) and CD (IBDQ scores of 6.1, 5.0, and 4.1, respectively). A similar inverse relation between clinical activity and quality of life was observed when EuroQol preference values were used. All 5 dimensions of the IBDQ showed significantly lower scores in patients with active UC and CD than in patients in remission. The pattern of scores by IBDQ dimensions differed between patients in relapse (who scored worse on the digestive symptoms dimension) and patients in remission. Variables related with disease activity, time of evolution since diagnosis and female sex, were significantly associated with having a worse perception of HRQOL. The type of disease or geographical area of residence did not influence results on the IBDQ.

CONCLUSIONS

UC and CD impair patients' HRQOL, and the degree of impairment depends on disease activity but is independent of the type of disease and place of residence.

[Clinical and electroencephalographic aspects of late infantile neuronal ceroid lipofuscinosis]

AIMS

In this paper we describe the clinical characteristics, and particularly the epileptic seizures and electroencephalographic findings, in 15 patients with a pathology diagnosis of late infantile neuronal ceroid lipofuscinosis (NCL).

PATIENTS AND METHODS

Nine female and six male patients were studied and their clinical records covering the period February 1990 to June 2003 were analysed. Neuroimaging, neurometabolic studies, ERG, PE and repeated EEG were carried out in all cases.

RESULTS

The mean age on onset of the disease was 3 years (range: 1-5 years). The initial symptom was epilepsy in all cases. Massive myoclonias and myoclonic-atonic seizures were the most frequent kinds of attacks. Focal myoclonias were observed in six patients. Other types of epileptic seizures observed included generalised tonic-clonic, absence, motor focal and complex focal. The epileptic seizures were resistant to therapy. Progressive neurological and visual impairment, pyramidal and cerebellar signs, as well as mental retardation were present in all cases. Intercritical EEG recordings showed diffuse paroxysms with spike and polyspike waves, multifocal spikes and, less often, focal spikes that were predominant in posterior regions. Photostimulation showed high amplitude (300-450) occipital spikes during the application of light stimulation between 1 and 8 Hz. ERG, VEP and SSEP results were pathological. Images showed signs of brain and cerebellar atrophy. Seven of the patients died between 8.5 and 11 years of age.

CONCLUSIONS

Late infantile NCL must be considered in the case of a child aged between 1 and 5 years who presents seizures that are predominantly generalised myoclonias and myoclonic-atonic, in association with progressive neurological deterioration including pyramidal, cerebellar and visual signs and an EEG trace showing occipital paroxysms triggered by low frequency photostimulation.

[Preoperative lymphoscintigraphy to identify the sentinel lymph node in breast cancer]

INTRODUCTION

The preoperative lymphoscintigraphy to the Sentinel Node Biopsy (SNB) can reproduce the lymphatic drainage of the tumour in breast cancer.

OBJECTIVES

To establish the pattern of lymphatic drainage of the mammary tumors by means of isotopic lymphoscintigraphy and determine the factors that could influence the negativity of the scintigraphy.

METHODS

121 patients with breast cancer who were going to undergo mammary surgery were studied with SNB. One day before the operation, 37 MBq 99mTc-colloidal sulphide colloid in a volume of 2 ml was injected in peritumoral tissue. Mammary lymphoscintigraphies were performed at 30 minutes and 18 hours P.I., in ANT and OA projections of the corresponding chest. After, the clinical-biological parameters and their influence on the result of the lymphoscintigraphy were analyzed.

RESULTS

The scintigraphy were positive in 85 % of the patients. The axillary chain was observed in 97 % and the internal mammary chain in 11 %. The factors associated to the absence of visualization of the sentinel node were: older than 50 years (94 %), menopause (89 %), tumoral size > or = 2 cm (67 %), axillary metastases (67 %), the overexpression of C-erbB-2 oncoprotein (44 %) and proliferative activity > 10 % (67 %).

CONCLUSIONS

The peritumoral injection of the radiocolloid establishes the lymphatic drainage pattern in the patients with breast cancer. Its absence of visualization can be associated to circumstances like: age > or = 50 years, menopause, tumoral size > or = 2 cm, axillary metastases, tumoral overexpression of the C-erbB-2 oncoprotein and high proliferative activity of the mammary tumor.

A catalogue of molecular, physiological and symbiotic properties of soybean-nodulating rhizobial strains from different soybean cropping areas of China

We have analysed 198 fast-growing soybean-nodulating rhizobial strains from four different regions of China for the following characteristics: generation time; number of plasmids; lipopolysaccharide (LPS), nodulation factors (LCOs) and PCR profiles; acidification of growth medium; capacity to grow at acid, neutral, and alkaline pH; growth on LC medium; growth at 28 and 37 degrees C; melanin production capacity; Congo red absorption and symbiotic characteristics. These unbiased analyses of a total subset of strains isolated from specific soybean-cropping areas (an approach which could be called "strainomics") can be used to answer various biological questions. We illustrate this by a comparison of the molecular characteristics of five strains with interesting symbiotic properties. From this comparison we conclude, for instance, that differences in the efficiency of nitrogen fixation or competitiveness for nodulation of these strains are not apparently related to differences in Nod factor structure.

Detection and monitoring of clonality in peripheral blood and bone marrow of patients with B-cell lymphoproliferative disorders

Bone marrow (BM) is accepted as the tissue of choice for the detection of monoclonal populations in leukemias and lymphomas; however, obtaining BM can be painful and traumatic for the patients. Although it is possible to detect clonality in peripheral blood (PB) samples, there are no reports comparing the results observed from BM with those from PB. Lymphoblastic leukemias and lymphomas are derived from B-lymphocytes in 80% of cases. In the early stages of their maturation, the immunoglobulin heavy chain genes (IgH) undergo rearrangements among their V, D, and J segments, giving rise to the Complementarity Determining Regions (CDR). Of these, CDR3 is unique for each lymphocyte and therefore it can be used as a tumour-specific marker in these malignant disorders. Among the 104 patients from whom we obtained pre-treatment paired samples of PB and BM, 94 (90.4%) showed concordant results. Similarly, at the end of treatment, 40 of 44 patients (90.9%) showed this concordance. During treatment only 24 patients were monitored and monoclones disappeared in 12 patients; in the other half, they persisted either partial or totally. We demonstrate that the detection and monitoring of monoclonal populations in the PB, in comparison with BM, was achieved with a statistical sensitivity of 90% and specificity of 92%.

FIGO Save the Mothers Initiative: the Central America and USA collaboration

The American College of Obstetricians and Gynecologists (ACOG) and the Central American Federation of Associations and Societies of Obstetrics and Gynecology (FECASOG), as a part of the FIGO Save the Mothers Initiative, undertook a pilot project to improve provision of basic emergency obstetric care in selected departments in four Central American countries. This article describes the process of the development and implementation of the project. Preliminary results suggest that the capacity to provide this care has been improved by the training of healthcare personnel.

Therapeutic effect of phenantroline in two rat models of inflammatory bowel disease

BACKGROUND

Phenantroline is a zinc-chelator that inhibits biological activities of matrix metalloproteinases (MMPs). Over-expression of MMPs can accelerate tissue destruction and disrupt subsequent tissue repair. The effects of phenantroline in two rat models of inflammatory bowel disease (IBD) are evaluated: transmural colitis induced by trinitrobenzensulphonic acid (TNBS) and distal colitis caused by dextran sulphate sodium (DSS).

METHODS

Transmural colitis was induced by TNBS in two groups of 15 rats each, and distal colitis was induced by DSS in two other groups of 15 rats each. Phenantroline was administered by oral gavage at 20 mg kg(-1) day(-1) to the test groups, whereas matched control groups received oral vehicle. On the last day of dosing, rats were subjected to intracolonic dialysis under anaesthesia for assessment of luminal eicosanoid release (PGE2, TXB2 and LTB4) and euthanized. Colons were removed and lesions were blindly scored according to macroscopic and histological scales. Myeloperoxidase (MPO) activity was measured in homogenates of colonic tissue.

RESULTS

In the TNBS model, phenantroline treatment significantly reduced colonic strictures; in the DSS model, phenantroline significantly decreased scores of epithelial injury. In both models, the levels of PGE2, TXB2 and LTB4 and tissue MPO were not significantly altered.

CONCLUSIONS

Although phenantroline did not modify the activity of inflammatory mediators, this compound substantially reduced intestinal injury associated with tissue remodelling.

Chromatin and histones from Giardia lamblia: a new puzzle in primitive eukaryotes

The three deepest eukaryote lineages in small subunit ribosomal RNA phylogenies are the amitochondriate Microsporidia, Metamonada, and Parabasalia. They are followed by either the Euglenozoa (e.g., Euglena and Trypanosoma) or the Percolozoa as the first mitochondria-containing eukaryotes. Considering the great divergence of histone proteins in protozoa we have extended our studies of histones from Trypanosomes (Trypanosoma cruzi, Crithidia fasciculata and Leishmania mexicana) to the Metamonada Giardia lamblia, since Giardia is thought to be one of the most primitive eukaryotes. In the present work, the structure of G. lamblia chromatin and the histone content of the soluble chromatin were investigated and compared with that of higher eukaryotes, represented by calf thymus. The chromatin is present as nucleosome filaments which resemble the calf thymus array in that they show a more regular arrangement than those described for Trypanosoma. SDS-polyacrylamide gel electrophoresis and protein characterization revealed that the four core histones described in Giardia are in the same range of divergence with the histones from other lower eukaryotes. In addition, G. lamblia presented an H1 histone with electrophoretic mobility resembling the H1 of higher eukaryotes, in spite of the fact that H1 has a different molecular mass in calf thymus. Giardia also presents a basic protein which was identified as an HU-like DNA-binding protein usually present in eubacteria, indicating a chimaeric composition for the DNA-binding protein set in this species. Finally, the phylogenetic analysis of selected core histone protein sequences place Giardia divergence before Trypanosoma, despite the fact that Trypanosoma branch shows an acceleration in the evolutionary rate pointing to an unusual evolutionary behavior in this lineage.