bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional activity of CD44 isoforms in haemopoiesis of the rat
Authors: Khaldoyanidi Sophia , Schnabel Doris , Föhr Nicole , Zöller Margot
Published: January 2007

Summary. Expression of CD44 is involved in the maturation as well as the homing of haemopoietic progenitor cells. Whether these processes are mediated by CD44 standard (CD44s) or variant (CD44v) isoforms is unknown. To assign functional activities of CD44 in haemopoiesis of the rat to distinct isoforms, ligand binding of haemopoietic progenitor cells was inhibited by monoclonal antibodies recognizing an epitope on CD44s (0x50) or CD44 exon v6 (1.1 ASML).

The vast majority of rat bone marrow cells (BMC) as well as stromal cells and non‐adherent cells in long‐term bone marrow culture (LTBMC) expressed CD44s. Bone marrow cells and non‐adherent cells in LTBMC, but not the stromal cells, also contained a population of large and granulated cells, which stained with anti‐CD44v6. In vivo and in vitro reconstitution experiments revealed that homing of BMC as well as settlement on stromal elements was influenced exclusively by anti‐CD44s, which also inhibited proliferation of progenitor cells. Anti‐CD44v6 had no influence on homing and seeding, but interfered with stroma formation and progenitor maturation. Finally. restoration of functional activity of T‐lineage cells was impaired in the presence of anti‐CD44v6.

The data indicate that CD44s and CD44v6 fulfilled distinct functions in haemopoiesis of the rat. Although CD44s facilitated homing and expansion of stem cells/progenitor cells, CD44v6 was involved in differentiation processes, particularly of lymphoid progenitor cells.
Shrinkage of initially very wet soil blocks, cores and clods from a range of European Andosol horizons
Authors: Bartoli F. , Begin J. C. , Burtin G. , Schouller E.
Published: January 2007

In advanced stages of volcanic ash soil formation, when more clay is formed, soil porosity values and soil water retention capacities are large and the soils show pronounced shrinkage on drying. Soil shrinkage is a key issue in volcanic soil environments because it often occurs irreversibly when topsoils dry out after changes from permanent grassland or forest to agriculture. European Andosols have developed in a wide range of climatic conditions, leading to a wide range in intensity of both weathering and organo‐mineral interactions. The question arises as to whether these differences affect their shrinkage properties. We aimed to identify common physically based shrinkage laws which could be derived from soil structure, the analysis of soil constituents, the selected sampling size and the drying procedure. We found that the final volumetric shrinkage of the initially field‐wet (56–86% of total porosity) or capillary‐wet (87–100% of total porosity) undisturbed soil samples was negatively related to initial bulk density and positively related to initial capillary porosity (volumetric soil water content of soil cores after capillary rise). These relationships were linear for the soil clods of 3–8 cm3, with final shrinkage ranging from 21.2 to 52.2%. For soil blocks of 240 cm3 and soil cores of 28.6 cm3 we found polynomial and exponential relationships, respectively, with thresholds separating shrinkage and nearly non‐shrinkage domains, and larger shrinkage values for the soil cores than for the soil blocks. For a given sample size, shrinkage was more pronounced in the most weathered and most porous Andosol horizons, rich in Al‐humus, than in the less weathered and less porous Andosol horizons, poor in Al‐humus. The Bw horizons, being more weathered and more porous, shrank more than the Ah horizons. We showed that the structural approach combining drying kinetics under vacuum, soil water analysis and mercury porosimetry is useful for relating water loss and shrinkage to soil structure and its dynamics. We also found that the more shrinkage that occurred in the Andosol horizon, the more pronounced was its irreversible mechanical change.
Changes in the macro‐pore structure of restored soil caused by compaction beneath heavy agricultural machinery: a morphometric study
Authors: Schäffer B. , Stauber M. , Müller R. , Schulin R.
Published: January 2007

Compaction can seriously degrade soil in modern agriculture. Soil that has been temporarily removed and stored is particularly sensitive to compaction when restored, although little is known about the structural changes in such soils under mechanical loads. We investigated the structural changes in a restored soil that had been gently cultivated for several years and then was trafficked by a heavy combine harvester, analysing the macro‐pore structure by quantitative morphometry of three‐dimensional microcomputed tomography images. Increased trafficking caused decreases in both the porosity and connectivity of the macro‐pores. The fraction of spherical pores (and thus the convexity of the pore space) and the mean pore separation were increased. Trafficking had no clear effect on the orientation of pores. While the mean pore diameter tended to decrease, biopores were more stable than interaggregate pores originating from the packing of soil aggregates. This is relevant for the development of structural stability in restored soils, as the macro‐pores consist mainly of interaggregate pores initially, whereas biopores develop and increase in proportion only gradually over time. Quantitative morphometry provides valuable morphological indices for the objective assessment of the macro‐pore structure and changes induced by compaction.
Characterization of Minaçu virus (Reoviridae: Orbivirus) and pathological changes in experimentally infected newborn mice
Authors: Martins Lívia C. , Diniz José A. P. , Silva Eliana V. P. , Barros Vera L. R. S. , Monteiro Hamilton A. O. , Azevedo Raimunda S. S. , Quaresma Juarez A. S. , Vasconcelos Pedro F. C.
Published: January 2007

Minaçu virus was isolated from Ochlerotatus scapularis (Diptera: Culicidae) in Minaçu, Goiás State, Brazil, in 1996. In attempting characterization of virus serological (hemagluttination inhibition, HI; indirect immunofluorescence assay, IFA), physicochemical [test for deoxycholate acid (DCA) sensitivity; polyacrylamide gel electrophoresis (PAGE)] tests and ultrastructural studies were made. Virus was also assayed in suckling mice after intracerebral inoculation of 0.02 ml and in VERO and C6/36 cells with 0.1 ml of viral suspension containing 105 LD50/ml. Inoculated and control systems were observed daily. Every 24 h, one control and two inoculated animals were killed for tissue testing, including histopathological changes by haematoxylin and eosin (HE)‐stained sections, which were semi‐quantified. Research into viral antigen in the tissues of mice [central nervous system (CNS), liver, heart, lungs, spleen and kidneys] was carried out by the immunohistochemical technique using the peroxidase system. The virus only replicated in VERO cells, with antigen positive by IFA. Positive complement fixation tests were only obtained using antiserum of Minaçu virus. Minaçu virus is DCA resistant; haemagglutinating activity was negative. By electronic microscopy non‐enveloped virus particles were 75 nm in diameter. PAGE analysis showed Minaçu virus genome profile with 10 RNA segments. Infected, non‐killed animals died 7 days after inoculation. Tissue lesions were observed in all organs, except the lungs. Intense lesions were observed in the CNS and the heart, where neurone and cardiocyte necroses, respectively, were noted. The liver, spleen and kidneys had moderate tissue changes. Viral antigens were more abundant in the CNS and the heart, and absent in the lungs. In conclusion, Minaçu virus belongs to the family Reoviridae, genus Orbivirus.
Modified method of AgNOR staining for tissue and interpretation in histopathology
Authors: Bukhari Mulazim Hussain , Niazi Shahida , Khan Saeed Akhter , Hashmi Ihsanulla , Perveen Shahida , Qureshi Shahzad Shafqat , Chaudhry Naseer Ahmed , Qureshi G. R. , Hasan Mumtaz
Published: January 2007

This study was conducted in the department of Pathology King Edward Medical University, from June to December 2002 to introduce the new method of AgNOR staining and its interpretation to increase its reliability. A total of 60 brain specimens were stained with modified AgNOR technique. The diagnosis of malignancy was made on H & E staining. AgNOR counts, variation in size and dispersion of AgNOR dots in cells were graded and compared in malignant and non‐malignant lesions. Modified method of AgNOR staining and interpretation was an easy, reliable and reproducible alternative to traditional AgNOR techniques for evaluating proliferation activity of cells in malignant and benign brain lesions. mAgNOR counts of different grades of astrocytoma (2.97 ± 0.96, 3.97 ± 0.43, 6.01 ± 2.74 and 8.01 ± 3.56) were significantly (P < 0.01) greater when compared with counts of normal brain (0.40 ± 0.01), and reactive gliosis (0.60 ± 0.01). AgNOR size and dispersion were of higher grade in a significantly greater proportion of malignancy when compared with benign conditions (P < 0.05). The AgNOR dots were brighter and more clear with modified staining when compared with previous studies. We conclude that modified AgNOR staining technique is simple, quick and reliable to evaluate cell proliferation by detecting AgNORs size and dispersion. In future, AgNOR size and dispersion should be considered rather than the count only. We recommend the use of morphometry for AgNOR size in future. We also recommend the use of modified AgNOR staining for obtaining sound and confidant results in routine paraffin sections.
Using a stochastic model to examine the ecological, economic and ethical consequences of population control in a charismatic invasive species: mute swans in North America
Authors: ELLIS MARTHA M. , ELPHICK CHRIS S.
Published: January 2007

Although invasive species are widely recognized as a threat to native ecosystems, control or eradication plans can create controversy, particularly when target species are considered attractive or desirable by members of the public. Detailed consideration of both biological and non‐biological criteria when evaluating management proposals can better inform managers working with controversial species.

In this study, alternative strategies for controlling introduced populations of mute swans Cygnus olor during the first few decades of population growth were compared in terms of ecological, economic and ethical considerations using a simple population model.

By quantifying parameter uncertainty with a stochastic model, we identified, in quantitative terms, management strategies that were predicted to have a high certainty of succeeding. Survival rates should be reduced by more than 17% to be 90% certain of a decline; reproductive rates would need to decline by more than 72% to achieve the same goal. Populations in which density dependence occurs are expected to need even greater effort for management to work.

Reducing survival rates was also more efficient economically; reducing population growth via reduced reproduction required three to four times more person‐days within the first year across a range of simulated growth rates.

Prolonging timelines for implementing management increased the number of swans that would have to be killed and the costs that would be required for reaching target population sizes.

Synthesis and applications. Because of controversy surrounding swan management, various considerations must be addressed when weighing control options. Our modelling suggests that, if a population is to be controlled, a period of intensive culling of adults will be the most efficient option in terms of biological effectiveness, economic costs and minimizing the total number of swans that ultimately are killed.
Mortality and prognostic factors in patients with obesity‐hypoventilation syndrome undergoing noninvasive ventilation
Authors: Budweiser S. , Riedl S. G. , Jörres R. A. , Heinemann F. , Pfeifer M.
Published: January 2007

Objectives.  The incidence of obesity‐hypoventilation syndrome (OHS) has greatly increased over time, but data on long‐term outcome are limited. We investigated survival and prognostic factors in these patients undergoing noninvasive positive pressure ventilation (NPPV).

Design.  Retrospective descriptive analysis of patients with OHS and NPPV up to 10 years.

Methods.  Long‐term mortality and predictors of survival were assessed. Additionally, we evaluated changes in lung function, blood gas and laboratory parameters 5.7 ± 2.5 months after initiation of NPPV.

Results.  126 patients (BMI 44.6 ± 7.8 kg m−2; PaCO2 55.5 ± 7.7 mmHg) were followed for 41.3 ± 27.6 months. Upon follow‐up, blood gases (daytime and nighttime), as well as pulmonary function improved, whilst haemoglobin and BMI decreased (P < 0.001 each). Adherence to NPPV was high (94.5% continuing NPPV 6.5 ± 2.3 h day−1). All‐cause mortality was 12.7%, with 1‐, 2‐ and 5‐year survival of 97.1%, 92.0% and 70.2%, respectively. In univariate analysis, patients with PaO2 <50 mmHg, C‐reactive protein ≥ 5.1 mg L−1, leucocytes ≥ 7.8 × 103 μl−1, or pH ≥ 7.44 at baseline had poor prognosis (P < 0.05 each). In Cox multivariate analysis, PaO2, pH and leucocytes were independent predictors of mortality. Reduction in nocturnal PaCO2 by ≥23.0% and haemoglobin at follow‐up was associated with improved survival (P < 0.05 each) whilst a decrease in pH was a predictor of increased mortality. In contrast, neither baseline BMI nor its change was linked to survival.

Conclusion.  Gas exchange and lung function in OHS were improved after initiation of NPPV. Hypoxemia, high pH and elevated inflammation markers predicted poor survival. Overall, NPPV was well tolerated and survival was excellent when compared with data from historical matched controls.
Molecular dissection and expression of the LdK39 kinesin in the human pathogen, Leishmania donovani
Authors: Gerald Noel J. , Coppens Isabelle , Dwyer Dennis M.
Published: January 2007

In this study we show for the first time the intracellular distribution of a K39 kinesin homologue in Leishmania donovani, a medically important parasite of humans. Further, we demonstrated that this motor protein is expressed in both the insect and mammalian developmental forms (i.e. promastigote and amastigotes) of this organism. Moreover, in both of these parasite developmental stages, immunofluorescence indicated that the LdK39 kinesin accumulated at anterior and posterior cell poles and that it displayed a peripheral localization consistent with the cortical cytoskeleton. Using a molecular approach, we identified, cloned and characterized the first complete open reading frame for the gene (LdK39) encoding this large (> 358 kDa) motor protein in L. donovani. Based on these observations, we subsequently used a homologous episomal expression system to dissect and express the functional domains that constitute the native molecule. Cell fractionation experiments demonstrated that LdK39 was soluble and that it bound to detergent‐extracted cytoskeletons of these parasites in an ATP‐dependent manner. The cumulative results of these experiments are consistent with LdK39 functioning as an ATP‐dependent kinesin which binds to and travels along the cortical cytoskeleton of this important human pathogen.
Bacterial sensing of and resistance to gold salts
Authors: Checa Susana K. , Espariz Martín , Audero María E. Pérez , Botta Pablo E. , Spinelli Silvana V. , Soncini Fernando C.
Published: January 2007

The MerR family is a group of bacterial transcriptional regulators that respond to different environmental stimuli, such as heavy metals, oxidative stress or antibiotics. Here we characterize a new member of this family that is highly selective for Au ions. We show that this Salmonella regulator, named GolS, directly controls the expression of at least two transcriptional units specifically required for Au resistance. By chromosomal mutagenesis, we demonstrated that Au‐selectivity is accomplished by a metal‐binding motif in GolS. Among the monovalent metal‐ion sensing MerR regulators GolS clusters in a branch distant from enterobacterial CueR orthologues. We propose that GolS and its homologues evolved to cope with toxic concentration of Au ion, allowing microorganisms to withstand contaminated environments.
Scavenging of the cofactor lipoate is essential for the survival of the malaria parasite Plasmodium falciparum
Authors: Allary Marina , Lu Jeff Zhiqiang , Zhu Liqun , Prigge Sean T.
Published: January 2007

Lipoate is an essential cofactor for key enzymes of oxidative metabolism. Plasmodium falciparum possesses genes for lipoate biosynthesis and scavenging, but it is not known if these pathways are functional, nor what their relative contribution to the survival of intraerythrocytic parasites might be. We detected in parasite extracts four lipoylated proteins, one of which cross‐reacted with antibodies against the E2 subunit of apicoplast‐localized pyruvate dehydrogenase (PDH). Two highly divergent parasite lipoate ligase A homologues (LplA), LipL1 (previously identified as LplA) and LipL2, restored lipoate scavenging in lipoylation‐deficient bacteria, indicating that Plasmodium has functional lipoate‐scavenging enzymes. Accordingly, intraerythrocytic parasites scavenged radiolabelled lipoate and incorporated it into three proteins likely to be mitochondrial. Scavenged lipoate was not attached to the PDH E2 subunit, implying that lipoate scavenging drives mitochondrial lipoylation, while apicoplast lipoylation relies on biosynthesis. The lipoate analogue 8‐bromo‐octanoate inhibited LipL1 activity and arrested P. falciparum in vitro growth, decreasing the incorporation of radiolabelled lipoate into parasite proteins. Furthermore, growth inhibition was prevented by lipoate addition in the medium. These results are consistent with 8‐bromo‐octanoate specifically interfering with lipoate scavenging. Our study suggests that lipoate metabolic pathways are not redundant, and that lipoate scavenging is critical for Plasmodium intraerythrocytic survival.
Malignant predominantly minigemistocytic glioma in two infants: a distinctive glioma variant?
Authors: Haberler C. , Slavc I. , Czech T. , Prayer D. , Pirker C. , Budka H. , Hainfellner J. A.
Published: January 2007

We report unusual distinctive histopathological features in malignant supratentorial tumours of two infants (patient 1: congenital, patient 2: 30 months). Both patients had paraventricularly located well‐delineated tumours. Gross total resection could be performed and postoperative chemotherapy was administered. At the last follow‐up, 18 (patient 1) and 10 months (patient 2) postoperatively, both patients were in continuous complete remission. Histologically, both tumours were characterized by high cellular density and monomorphic appearance. Tumour cells were small to medium‐sized and the majority of cells showed a distinctive minigemistocytic shape. A small fraction of cells lacked a distinct cytoplasm. Mitotic figures were abundant, tumour necrosis and hypertrophic vascular proliferations were absent. Immunohistochemically, the tumour cells expressed glial (GFAP, S100) and focally neuronal (NFP) proteins. Comparative genomic hybridization showed few, dissimilar chromosomal aberrations in the two tumours. Although sharp demarcation and monomorphic architecture of both tumours are reminiscent of a primitive neuroectodermal tumour, cytological and immunohistochemical glial differentiation refer to a glial tumour origin. To our knowledge the histopathological features of the described tumours do not correspond unequivocally to any established glioma variant and could represent a distinctive new glioma subtype.
Role of tumour necrosis factor α, but not of cyclo‐oxygenase‐2‐derived eicosanoids, on functional and morphological indices of dystrophic progression in mdx mice: a pharmacological approach
Authors: Pierno S. , Nico B. , Burdi R. , Liantonio A. , Didonna M. P. , Cippone V. , Fraysse B. , Rolland J.‐F. , Mangieri D. , Andreetta F. , Ferro P. , Camerino C. , Zallone A. , Confalonieri P. , De Luca A.
Published: January 2007

The role of tumour necrosis factor (TNF)‐α or cyclo‐oxygenase‐2 (COX‐2) eicosanoids in dystrophinopathies has been evaluated by chronically treating (4–8 weeks) adult dystrophic mdx mice with the anti‐TNF‐α etanercept (0.5 mg/kg) or the COX‐2 inhibitor meloxicam (0.2 mg/kg). Throughout the treatment period the mdx mice underwent a protocol of exercise on treadmill in order to worsen the pathology progression; gastrocnemious muscles from exercised mdx mice showed an intense staining for TNF‐α by immunohistochemistry. In vivo, etanercept, but not meloxicam, contrasted the exercise‐induced forelimb force drop. Electrophysiological recordings ex vivo, showed that etanercept counteracted the decrease in chloride channel function (gCl), a functional index of myofibre damage, in both diaphragm and extensor digitorum longus (EDL) muscle, meloxicam being effective only in EDL muscle. None of the drugs ameliorated calcium homeostasis detected by electrophysiology and/or spectrofluorimetry. Etanercept, more than meloxicam, effectively reduced plasma creatine kinase (CK). Etanercept‐treated muscles showed a reduction of connective tissue area and of pro‐fibrotic cytokine TGF‐β1 vs. untreated ones; however, the histological profile was weakly ameliorated. In order to better evaluate the impact of etanercept treatment on histology, a 4‐week treatment was performed on 2‐week‐old mdx mice, so to match the first spontaneous degeneration cycle. The histology profile of gastrocnemious was significantly improved with a reduction of degenerating area; however, CK levels were only slightly lower. The present results support a key role of TNF‐α, but not of COX‐2 products, in different phases of dystrophic progression. Anti‐TNF‐α drugs may be useful in combined therapies for Duchenne patients.
Haemonchus contortus intestine: a prominent source of mucosal antigens
Authors: JASMER D. P. , LAHMERS K. K. , BROWN W. C.
Published: January 2007

We sought to identify antigens from Haemonchus contortus, an abomasal nematode of small ruminants, that stimulate local (abomasal lymph node, ALN) CD4+ T lymphocyte responses during a primary infection. Results led to a focus on antigens from the parasite intestine. The H. contortus intestine proved to be a major source of antigens that stimulated ALN CD4+, CD25+ T lymphocyte responses during infections in lambs. When stimulated by intestinal antigens, ALN lymphocytes from these lambs expressed IL‐4 and IL‐13 transcripts, and, more variably, IFN‐γ. An immunoaffinity‐purified fraction, enriched for H. contortus apical intestinal membrane proteins, stimulated similar ALN responses. On further fractionation, antigens from six size classes (ranging from 30 to 200 kDa) also stimulated proliferation of ALN lymphocytes. Mass spectrometry analysis of these size classes identified several known apical intestinal membrane proteins from H. contortus. The results show that H. contortus intestinal antigens warrant investigation in strategies to induce mucosal immunity against this parasite. The specific proteins identified have value for this purpose. The results are in contrast with the now generalized idea that H. contortus intestinal antigens are ‘hidden’ from the host immune system, and this issue is discussed. The approach also has potential application to other gastrointestinal nematode parasites.
CCL2‐independent role of CCR2 in immune responses against Leishmania major
Authors: QUINONES M. P. , ESTRADA C. A. , JIMENEZ F. , MARTINEZ H. , WILLMON O. , KUZIEL W. A. , AHUJA S. K. , AHUJA S. S.
Published: January 2007

The chemokine CCL2 (MCP‐1) and its receptor CCR2 modulate leucocyte migration and T helper differentiation. CCL2 or CCR2 knockout (KO) mice have divergent phenotypes following infection with the intracellular parasite Leishmania major (L. major). Compared to wild‐type (WT) mice, intradermally infected CCR2 KO mice in the L. major‐resistant C57BL/6j background become susceptible and fail to generate protective Th1 responses. In contrast, subcutaneously infected CCL2 KO mice in the L. major‐susceptible BALB/c background are resistant and exhibit reduced pathogenic Th2 responses. Here we explore two variables that may account for this contrasting outcome, namely background strain and route of infection. We found that the CCR2‐null state, both in the BALB/c and the C57BL/6j background, was associated with increased susceptibility to intradermal or subcutaneous L. major infection. Notably, the CCL2‐null state did not change the ability of C57BL/6j mice to mount protective responses following intradermal infection. Dual genetic inactivation of CCR2 and CCL2 in the L. major‐resistant C57BL/6j background resulted in a shift to a susceptible phenotype analogous to that of CCR2 KO in the C57BL/6j background. We concluded that CCL2‐independent effects of CCR2 are indispensable for the control of L. major infection and the generation of protective immune responses.
Jurassic‐to‐present thermal history of the central High Atlas (Morocco) assessed by low‐temperature thermochronology
Authors: Barbero Luis , Teixell Antonio , Arboleya María‐Luisa , Río Pedro del , Reiners Peter W. , Bougadir Blaid
Published: January 2007

Apatite fission track (AFT) and (U–Th)/He data from the High Atlas have been obtained for the first time to constrain the tectono‐thermal evolution of the central part of the chain. Results from Palaeozoic basement massifs indicate long residence at low temperatures, consistently with their original location out of the deepest Mesozoic rift troughs and indicating minor exhumation. The best rocks for extracting the Alpine history of the Atlas Mountains are Jurassic intrusives, which yield AFT ages centred on c. 80 Ma; thermal models based on AFT data and constrained by (U–Th)/He suggest that these ages are included in a slow cooling trend from intrusion age to c. 50 Ma ago that we attribute to post‐rift thermal relaxation. This is followed by a stability period of c. 30 Ma and then by a final exhumational cooling until present exposure. Eocene intrusives yield AFT ages similar to those of Rb–Sr and K–Ar suggesting rapid emplacement in the uppermost crust.
Associations between USF1 gene variants and cardiovascular risk factors in the Quebec Family Study
Authors: Choquette AC , Bouchard L , Houde A , Bouchard C , Pérusse L , Vohl M‐C
Published: January 2007

Cardiovascular (CVD) risk factors are under the influence of environmental and genetic factors. Human upstream transcription factor 1 gene (USF1) encodes for a transcription factor, which modulates the expression of genes involved in lipid and carbohydrate metabolic pathways. The aim of this study was to test the hypothesis that USF1 gene variants are associated with CVD risk factors in the Quebec Family Study (QFS). USF1 has been sequenced in 20 QFS subjects with high plasma apolipoprotein B100 (APOB) levels (>1.14 g/l) and small, dense low‐density lipoprotein (LDL) particles (≥250.7 Å and ≤255.9 Å), as well as in five subjects with larger LDL particles. Ten variants were identified in non‐coding regions of USF1. Two of these polymorphisms (intron 7 c.561–100 G>A, and exon 11 c.*187 C>T) as well as the c.‐56 A>G polymorphism, were genotyped and analyzed in 760 subjects from QFS. Association studies showed that women with c.561‐100 A/A and c.*187 T/T genotypes had more favorable adiposity indices (<0.04). In summary, significant associations between relatively common USF1 genetic variants and CVD risk factors were observed in French Canadians.
Rubber tree (Hevea brasiliensis) trunk phloem necrosis: aetiological investigations failed to confirm any biotic causal agent
Authors: Pellegrin F. , Duran‐Vila N. , Van Munster M. , Nandris D.
Published: January 2007

Trunk phloem necrosis (TPN) is currently a main constraint in rubber (Hevea brasiliensis) plantations. The apparent spread of the disease, from tree to tree along the planting line, strongly supported the implication of a pathogen that could be transmitted mechanically via the tapping knife. In order to detect a causal agent of the disease, studies focusing on characterization of the known mechanically transmitted pathogens (e.g. viroids, cryptic viruses or phytoplasma) were initiated. RNA strands of low molecular weight (200–400 and >500 bp) displaying structural similarities with viroids and viral dsRNAs were observed in various tested samples. However, attempts to show the potential role of these RNA molecules in the spread of the disease failed. First of all, there was no significant or reproducible correlation between the health status of the rubber trees sampled and these RNA molecules. Moreover, no sequence homology with known pathogens could be found when randomly amplified cDNA fragments isolated from trees presenting the disease symptoms were sequenced. In conclusion, the aetiological investigations, in order to show the presence of a pathogen responsible of the TPN disease, were non‐conclusive, which tends to disprove the hypothesis of a biotic causal agent.
Anatomical observations of Pseudomonas savastanoi on Rhamnus alaternus
Authors: Temsah M. , Hanna L. , Saad A. T.
Published: January 2007

Buckthorn (Rhamnus alaternus) was recently reported as a new host of Pseudomonas savastanoi. The main symptom on buckthorn is the formation of knots on stems, branches and occasionally on leaves. Knot formation and anatomical changes in host tissues induced by P. savastanoi were studied macroscopically and by light microscopy. Inoculation of buckthorn shoots with P. savastanoi initiated small green swellings that developed into normal size knots. The pathogen invades intercellular spaces of parenchyma tissues degrading cell walls and resulting in extensive cavities filled with bacterial cells. Many host cells contiguous to such cavities were plasmolysed and necrotic. Depending on the depth of the inoculation wound, parenchyma, cambium, ray parenchyma, and pith cells close to bacterial cavities enlarge and proliferate forming the fully grown knots. At later stages of knot development, the cambium appears dispersed in the knot and forms unoriented vascular tissues. Periderm surrounds bacterial cavities and outer layers of knots. These findings on buckthorn are compared with those reported to be caused by the same pathogen on ash, oleander and olive.
Diagnostic markers for Planococcus ficus (Signoret) and Planococcus citri (Risso) by random amplification of polymorphic DNA‐polymerase chain reaction and species‐specific mitochondrial DNA primers
Authors: Demontis M. A. , Ortu S. , Cocco A. , Lentini A. , Migheli Q.
Published: January 2007

Abstract:  Planococcus ficus (Signoret) and Planococcus citri (Risso) (Hom., Pseudococcidae) are important phytophagous components in different agroecosystems. The two species may coexist in the same environment and are most difficult to distinguish by morphological features. The aim of this study was to find genetic markers suitable for distinguishing P. ficus from P. citri, to assist in the rapid identification of field specimens. By using synthetic sex pheromone‐baited traps, pure male populations of both species were collected from a vineyard and from a citrus orchard in northern Sardinia, Italy. Individual males of citrus and vine mealybugs were preliminarily examined by the random amplification of polymorphic DNA (RAPD) technique. Among twelve 10‐mer random primers, the oligonucleotide OPL‐12 generated several markers suitable for distinguishing between the two species. This primer was then used to characterize individual males and females of both mealybug species collected near pheromone‐baited traps in vineyards and orange orchards from different geographic areas. Reference samples from other regions of southern Italy were also included. A clear differentiation of the two species was accomplished according to their pattern of amplification, thus confirming a high level of intra‐specific genetic homogeneity. Consequently, two fragments of the cytochrome c oxidase I gene from P. citri and P. ficus were compared and two pairs of species‐specific polymerase chain reaction (PCR) primers were developed based on diverging sequences. These primers allowed sensitive and reliable PCR identification of both males and females of P. citri and of P. ficus of different geographic origin.
Onion aphid (Neotoxoptera formosana) attractants, in the headspace of Allium fistulosum and A. tuberosum leaves
Authors: Hori M.
Published: January 2007

Abstract:  Attractancy of Allium fistulosum L. and Allium tuberosum Rottl. to adult apterae of the onion aphid, Neotoxoptera formosana (Takahashi), an oligophagous aphid pest of Allium crops, was investigated with a Y‐tube olfactometer. The aphids were significantly attracted to both A. fistulosum and A. tuberosum. The headspace components of both plants were extracted with solid‐phase microextraction (SPME) and analysed by gas chromatography‐mass spectrometry (GC‐MS). The main volatile components of A. fistulosum were dipropyl disulphide (relative contents: 67%), 1‐propenyl propyl disulphide (23%) and dipropyl trisulphide (6%). In the headspace of A. tuberosum, diallyl disulphide was detected as the main component (58%). Attractancy of dipropyl disulphide, dipropyl trisulphide and diallyl disulphide to the aphids was examined with the Y‐tube olfactometer. The aphids were significantly attracted to dipropyl trisulphide and diallyl disulphide at a concentration of 0.01%. Dipropyl disulphide did not significantly attract the aphids at any concentrations tested. It was revealed that attractancy of A. fistulosum and A. tuberosum was caused by dipropyl trisulphide and diallyl disulphide, respectively. The findings suggest that N. formosana uses these sulphur compounds, characteristic components of Allium plants, as olfactory cues to find the host plants.
Recurrent respiratory infections and phagocytosis in childhood
Authors: DON MASSIMILIANO , FASOLI LOLITA , GREGORUTTI VIVIANA , PISA FEDERICA , VALENT FRANCESCA , PRODAN MARIO , CANCIANI MARIO
Published: January 2007

Background: About 10% of pre‐school children has recurrent respiratory infections (RRI), which could be related to environmental and/or immunological factors. The aim of the present study has been to evaluate the impact of phagocytosis (FAG) and reactive oxygen intermediates (ROI) production deficiencies on pediatric RRI by the measurement of FAG and ROI activity of the polymorphonuclear neutrophils.

Methods: Serum immunoglobulins, IgG subclasses, lymphocytic subpopulations, FAG and ROI tests were measured in 90 children with RRI, in a moment of well‐being and off all medications for at least 4 weeks. FAG and ROI tests were also measured in 19 healthy children.

Results: FAG (91.4 ± 11.5%) and ROI (81.8 ± 17.5%) of patients resulted in significantly decreased measurements compared to the control values (95.2 ± 1.8% and 89.7 ± 4.8%, respectively). No significant difference was manifest between the mean values of FAG and ROI tests among the patients when they were divided for age (above and below 6 years). A significant decreased likelihood of abnormal ROI (odds ratio, 0.3; 95% confidence interval, 0.07–0.97) was found in the patients with low IgA.

Conclusions: The authors’ results permit only to suppose an etiological role of FAG and ROI deficiencies of polymorphonuclear neutrophils in the genesis of pediatric RRI, irrespective of the age of the patients, and further studies are necessary for confirmation.
Increased incidence of congenital hypothyroidism due to iodine deficiency
Authors: SAG˘LAM HALIL , BÜYÜKUYSAL LEVENT , KÖKSAL NILGÜN , ERCAN I˙LKER , TARIM ÖMER
Published: January 2007

Background: The incidence of congenital hypothyroidism (CH) is expected to be elevated in iodine‐deficient areas. In this study, the authors aimed to determine the incidence of transient and permanent CH in a large city which is known to be in the zone of moderate iodine deficiency.

Methods: Newborn babies in Bursa, Turkey, were screened by measurement of serum thyroid‐stimulating hormone (TSH) obtained by heel prick. The babies who had a serum TSH >20 mIU/L were recalled for measurement of T4 and TSH in venous serum.

Results: A total of 11 770 newborns were screened over a period of 9 years. The incidence of CH was found to be 1/840. However, after excluding the transient cases, permanent CH was diagnosed in 1/2354. It was impossible to distinguish transient patients from permanent CH by initial laboratory tests (P > 0.05). The estimated power of the study in determining the incidence of CH in the population was 90% (P < 0.05).

Conclusion: The authors conclude that the incidence of CH is very high in their population which warrants a country‐wide neonatal screening program. Since transient cases cannot be distinguished and untreated transient hypothyroidism may also cause mental retardation, treatment must be started as early as possible with frequent monitoring to optimize the outcome and identify the transient patients.
C117T variant in the SMN1 gene found in the Japanese population
Authors: SADEWA AHMAD HAMIM , HARADA YOSUKE , SASONGKO TEGUH HARYO , MATSUO MASAFUMI , NISHIO HISAHIDE
Published: January 2007

Background: The SMN genes are closely related to the development of spinal muscular atrophy (SMA); mutated SMN1 causes SMA and functional SMN2 modifies the severity of SMA. SMN1 and SMN2 are almost identical, being distinguished by only five base pair substitutions located at the 3’‐end of the genes. Recently, a synonymous DNA variant, C117T, has been identified at the first codon of SMN2 exon 2a in the Caucasian population. It is still a question whether the variant is specific to the Caucasian population, and whether it is found only in SMN2. In order to address these questions, Japanese populations were screened for the presence of C117T in the SMN genes.

Methods: To detect the C117T variant in a Japanese population, polymerase chain reaction–restriction fragment length polymorphism was performed in 33 SMA patients homozygous for SMN1 deletion and 106 control individuals. Reverse transcription–polymerase chain reaction (RT‐PCR) was performed to clarify whether the variant affects the splicing process of the SMN1 gene.

Results: The C117T variant was found in one out of 33 Japanese SMA patients (3.0%) and in seven out of 106 Japanese control individuals (6.6%). There was no significant difference between frequencies in the present data and those reported from the Caucasian population. Notably, the C117T variant was also detected in the SMN1 gene; a control individual with homozygous SMN2 deletion was found to have the variant on one of the SMN1 genes. RT‐PCR indicated that this variant of the SMN1 gene was normally transcribed and did not affect the splicing process in this individual.

Conclusions: The C117T variant was found not only in the Caucasian population, but also in the Japanese population. In addition, the variant was not specific to SMN2: it was also found in SMN1. RT‐PCR indicated that the variant did not affect the splicing process.
Clinical sepsis in neonates is responsible for the lower prevalence of developing allergy
Authors: RYOZAWA MANAMI , MATSUBARA TOMOYO , ICHIYAMA TAKASHI , UMEDA KAORU , FURUKAWA SUSUMU
Published: January 2007

Background: The hygiene hypothesis proposes an association between the change in exposure to microbes and the increased incidence of atopic disease. The purpose of the present study was to perform a prospective epidemiological study of the effect of perinatal infection on the development of allergy.

Methods: Eight hundred and ten children were born at Umeda Gynecological Hospital in Yamaguchi prefecture in Japan between April 1997 and March 1998. A questionnaire survey on the development of allergic diseases was sent by mail in 2002. The presence or absence of neonatal infectious disease (clinical sepsis) and maternal complications during the gestational period and delivery, and the incidence of bacterial infection during the perinatal period, were investigated by examining hospital records.

Results: Data were obtained for 410 children (51%). One hundred and forty‐eight children (36.1%) developed allergic diseases. Among children whose mothers had allergies, the percentage of children who developed allergic disease(s) was significantly lower in children who had had clinical sepsis in the neonatal period than in those without clinical sepsis (26.1% vs 49.7%, P < 0.03).

Conclusions: Clinical sepsis in neonates might reduce the risk of developing allergic diseases in early childhood in children whose mothers have allergies.
Changing trend of neonatal infection: Experience at a newly established regional medical center in Korea
Authors: PARK CHAN‐HOO , SEO JI‐HYUN , LIM JAE‐YOUNG , WOO HYANG‐OK , YOUN HEE‐SHANG
Published: January 2007

Background: The purpose of the present paper was to study the natural history of neonatal sepsis in a newly established neonatal intensive care center that started in 1988 at Gyeongsang National University Hospital 9 (GNUH) in Chinju city, Korea.

Methods: Neonates admitted to GNUH neonatal intensive care unit (NICU) between January 1988 and December 1997 were included. All organisms detected on blood and cerebrospinal fluid cultures were recorded. Neonatal sepsis was defined as ‘clinical signs suggestive of sepsis with a positive blood and/or cerebrospinal fluid culture during the neonatal period’. Temporal trends and the distribution of pathogens in identified septic patients during the aforementioned period were studied descriptively.

Results: Between January 1988 and 31 December 1997, 3327 neonates were admitted to the center. A total of 6.7% of neonates (224/3327) had at least one positive blood culture. The vast majority (62%) of septic cases were caused by Gram‐positive organisms. Coagulase‐negative staphylococci (CONS) were the most common pathogens (24% of all infections, 38% of Gram‐positive infections). The pathogen associated with the highest mortality was Klebsiella pneumoniae (25%, 10/39). Sepsis as a result of Gram‐negative pathogens (especially K. pneumoniae) were involved in outbreaks that occurred for a few years during the study interval.

Conclusions: The major outcome of this review was the emergence of CONS in the NICU during a relatively short period of time (10 years) as a common neonatal pathogen. This observation is similar to the experience of other centers over the last two decades.
Microbial community structure of ethanol type fermentation in bio‐hydrogen production
Authors: Ren Nanqi , Xing Defeng , Rittmann Bruce E. , Zhao Lihua , Xie Tianhui , Zhao Xin
Published: January 2007

Three continuous stirred‐tank reactors (CSTRs) were used for H2production from molasses wastewater at influent pH of 6.0–6.5 (reactor A), 5.5–6.0 (reactor B), or 4.0–4.5 (reactor C). After operation for 28 days, the microbial community formed ethanol type (C), propionate type (A) and ethanol‐butyrate‐mixed type (B) fermentation. The H2production rate was the highest for ethanol type fermentation, 0.40 l (g VSS)−1 day−1or 0.45 l H2 (g COD removed)−1. Microbial community dynamics and diversity were analysed using double‐gradient denaturing gradient gel electrophoresis (DG‐DGGE). Denaturing gradient gel electrophoresis profiles indicated that the community structures changed quickly in the first 14 days. Phylogenetic analysis indicated that the dominant bacterial groups were low G+C Gram‐positive bacteria,Bacteroides,γ‐ProteobacteriaandActinobacteria;α‐Proteobacteria,β‐Proteobacteria,δ‐ProteobacteriaandSpirochaeteswere also presented as minor groups in the three reactors. H2‐producing bacteria were affiliated withEthanoligenens,Acetanaerobacterium,Clostridium,Megasphaera,CitrobacterandBacteroides.An ethanol‐based H2‐producing bacterium,Ethanoligenens harbinenseCGMCC1152, was isolated from reactor C and visualized using fluorescencein situhybridization (FISH) to be 19% of the eubacteria in reactor C. In addition, isoenzyme activity staining for alcohol dehydrogenase (ADH) supported that the majority of ethanol‐producing bacteria were affiliated withEthanoligenensin the microbial community.
Methane‐derived carbon flows through methane‐oxidizing bacteria to higher trophic levels in aquatic systems
Authors: Deines Peter , Bodelier Paul L. E. , Eller Gundula
Published: January 2007

Recent investigations have shown that biogenic methane can be a carbon source for macro invertebrates in freshwater food webs. Stable carbon isotopic signatures, used to infer an organism's food source, indicated that methane can play a major role in the nutrition of chironomid larvae. However, the pathway of methane‐derived carbon into invertebrate biomass is still not confirmed. It has been proposed that chironomid larvae ingest methane‐oxidizing bacteria (MOB), but this has not been experimentally demonstrated to date. Using 13C‐labelled methane we could show for the first time that chironomid larvae assimilate methane‐derived carbon through MOB. Chironomid larval biomass was significantly 13C‐enriched after dwelling for 10 days in lake sediment enriched with labelled methane. Moreover, phospholipid fatty acids diagnostic for MOB were detected in larval tissue and were significantly 13C‐enriched, which encompasses the 13C‐uptake predicted for a methane‐based nutrition. Additionally, chironomid larvae fed on sediment and water‐column derived MOB biomass.
Biogeochemistry and biodiversity of methane cycling in subsurface marine sediments (Skagerrak, Denmark)
Authors: Parkes R. John , Cragg Barry A. , Banning Natasha , Brock Fiona , Webster Gordon , Fry John C. , Hornibrook Ed , Pancost Richard D. , Kelly Sam , Knab Nina , Jørgensen Bo B. , Rinna Joachim , Weightman Andrew J.
Published: January 2007

This biogeochemical, molecular genetic and lipid biomarker study of sediments (∼4 m cores) from the Skagerrak (Denmark) investigated methane cycling in a sediment with a clear sulfate‐methane‐transition zone (SMTZ) and where CH4 supply was by diffusion, rather than by advection, as in more commonly studied seep sites. Sulfate reduction removed sulfate by 0.7 m and CH4 accumulated below. 14C‐radiotracer measurements demonstrated active H2/CO2 and acetate methanogenesis and anaerobic oxidation of CH4 (AOM). Maximum AOM rates occurred near the SMTZ (∼3 nmol cm−3 day−1 at 0.75 m) but also continued deeper, overall, at much lower rates. Maximum rates of H2/CO2 and acetate methanogenesis occurred below the SMTZ but H2/CO2 methanogenesis rates were × 10 those of acetate methanogenesis, and this was consistent with initial values of 13C‐depleted CH4 (δ13C c.−80‰). Areal AOM and methanogenic rates were similar (∼1.7 mmol m−2 day−1), hence, CH4 flux is finely balanced. A 16S rRNA gene library from 1.39 m combined with methanogen (T‐RFLP), bacterial (16S rRNA DGGE) and lipid biomarker depth profiles showed the presence of populations similar to some seep sites: ANME‐2a (dominant), ANME‐3, Methanomicrobiales, Methanosaeta Archaea, with abundance changes with depth corresponding to changes in activities and sulfate‐reducing bacteria (SRB). Below the SMTZ to ∼1.7 m CH4 became progressively more 13C depleted (δ13C −82‰) indicating a zone of CH4 recycling which was consistent with the presence of 13C‐depleted archaeol (δ13C −55‰). Pore water acetate concentrations decreased in this zone (to ∼5 μM), suggesting that H2, not acetate, was an important CH4 cycling intermediate. The potential biomarkers for AOM‐associated SRB, non‐isoprenoidal ether lipids, increased below the SMTZ but this distribution reflected 16S rRNA gene sequences for JS1 and OP8 bacteria rather than those of SRB. At this site peak rates of methane production and consumption are spatially separated and seem to be conducted by different archaeal groups. Also AOM is predominantly coupled to sulfate reduction, unlike recent reports from some seep and gassy sediment sites.