bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic analysis of synaptotagmin-7 function in synaptic vesicle exocytosis
Authors: Maximov Anton , Lao Ye , Li Hongmei , Chen Xiaocheng , Rizo Josep , Sørensen Jakob B. , Südhof Thomas C.
Published: February 2008

Synaptotagmin-7 is a candidate Ca
2+
sensor for exocytosis that is at least partly localized to synapses. Similar to synaptotagmin-1, which functions as a Ca
2+
sensor for fast synaptic vesicle (SV) exocytosis, synaptotagmin-7 contains C
2
A and C
2
B domains that exhibit Ca
2+
-dependent phospholipid binding. However, synaptotagmin-7 cannot replace synaptotagmin-1 as a Ca
2+
sensor for fast SV exocytosis, raising questions about the physiological significance of its Ca
2+
-binding properties. Here, we examine how synaptotagmin-7 binds Ca
2+
and test whether this Ca
2+
binding regulates Ca
2+
-triggered SV exocytosis. We show that the synaptotagmin-7 C
2
A domain exhibits a Ca
2+
-binding mode similar to that of the synaptotagmin-1 C
2
A domain, suggesting that the synaptotagmin-1 and -7 C
2
domains generally employ comparable Ca
2+
-binding mechanisms. We then generated mutant mice that lack synaptotagmin-7 or contain point mutations inactivating Ca
2+
binding either to both C
2
domains of synaptotagmin-7 or only to its C
2
B domain. Synaptotagmin-7-mutant mice were viable and fertile. Inactivation of Ca
2+
binding to both C
2
domains caused an ≈70% reduction in synaptotagmin-7 levels, whereas inactivation of Ca
2+
binding to only the C
2
B domain did not alter synaptotagmin-7 levels. The synaptotagmin-7 deletion did not change fast synchronous release, slow asynchronous release, or short-term synaptic plasticity of release of neurotransmitters. Thus, our results show that Ca
2+
binding to the synaptotagmin-7 C
2
domains is physiologically important for stabilizing synaptotagmin-7, but that Ca
2+
binding by synaptotagmin-7 likely does not regulate SV exocytosis, consistent with a role for synaptotagmin-7 in other forms of Ca
2+
-dependent synaptic exocytosis.
Distinctive microRNA signature of acute myeloid leukemia bearing cytoplasmic mutated nucleophosmin
Authors: Garzon Ramiro , Garofalo Michela , Martelli Maria Paola , Briesewitz Roger , Wang Lisheng , Fernandez-Cymering Cecilia , Volinia Stefano , Liu Chang-Gong , Schnittger Susanne , Haferlach Torsten , Liso Arcangelo , Diverio Daniela , Mancini Marco , Meloni Giovanna , Foa Robin , Martelli Massimo F. , Mecucci Cristina , Croce Carlo M. , Falini Brunangelo
Published: February 2008

Acute myeloid leukemia (AML) carrying
NPM1
mutations and cytoplasmic nucleophosmin (NPMc+ AML) accounts for about one-third of adult AML and shows distinct features, including a unique gene expression profile. MicroRNAs (miRNAs) are small noncoding RNAs of 19–25 nucleotides in length that have been linked to the development of cancer. Here, we investigated the role of miRNAs in the biology of NPMc+ AML. The miRNA expression was evaluated in 85 adult
de novo
AML patients characterized for subcellular localization/mutation status of
NPM1
and
FLT3
mutations using a custom microarray platform. Data were analyzed by using univariate
t
test within BRB tools. We identified a strong miRNA signature that distinguishes NPMc+ mutated (
n
= 55) from the cytoplasmic-negative (
NPM1
unmutated) cases (
n
= 30) and includes the up-regulation of
miR-10a
,
miR-10b
, several
let-7
and
miR-29
family members. Many of the down-regulated miRNAs including
miR-204
and
miR-128a
are predicted to target several
HOX
genes. Indeed, we confirmed that
miR-204
targets
HOXA10
and
MEIS1
, suggesting that the
HOX
up-regulation observed in NPMc+ AML may be due in part by loss of
HOX
regulators-miRNAs.
FLT3
-ITD+ samples were characterized by up-regulation of
miR-155
. Further experiments demonstrated that the up-regulation of
miR-155
was independent from
FLT3
signaling. Our results identify a unique miRNA signature associated with NPMc+ AML and provide evidence that support a role for miRNAs in the regulation of
HOX
genes in this leukemia subtype. Moreover, we found that
miR-155
was strongly but independently associated with
FLT3
-ITD mutations.
A
trans
-Golgi network golgin is required for the regulated secretion of TNF in activated macrophages
in vivo
Authors: Lieu Zi Zhao , Lock John G. , Hammond Luke A. , La Gruta Nicole L. , Stow Jennifer L. , Gleeson Paul A.
Published: February 2008

The transmembrane precursor of tumor necrosis factor-α (TNF) exits the
trans
-Golgi network (TGN) in tubular carriers for subsequent trafficking and delivery to the cell surface; however, the molecular machinery responsible for Golgi export is unknown. We previously reported that members of the TGN golgin family are associated with subdomains and tubules of the TGN. Here, we show that the TGN golgin, p230/golgin-245 (p230), is essential for intracellular trafficking and cell surface delivery of TNF in transfected HeLa cells and activated macrophages. Live-cell imaging revealed that TNF transport from the TGN is mediated selectively by tubules and carriers marked by p230. Significantly, LPS activation of macrophages resulted in a dramatic increase of p230-labeled tubules and carriers emerging from the TGN, indicating that macrophages up-regulate the transport pathway for TNF export. Depletion of p230 in LPS-stimulated macrophages reduced cell surface delivery of TNF by >10-fold compared with control cells. To determine whether p230 depletion blocked TNF secretion
in vivo
, we generated retrogenic mice expressing a microRNA-vector to silence p230. Bone-marrow stem cells were transduced with recombinant retrovirus containing microRNA constructs and transplanted into irradiated recipients. LPS-activated peritoneal macrophages from p230 miRNA retrogenic mice were depleted of p230 and had dramatically reduced levels of cell surface TNF. Overall, these studies have identified p230 as a key regulator of TNF secretion and have shown that LPS activation of macrophages results in increased Golgi carriers for export. Also, we have demonstrated a previously undescribed approach to control cytokine secretion by the specific silencing of trafficking machinery.
Symmetry of planar four-body convex central configurations
Authors: Albouy Alain , Fu Yanning , Sun Shanzhong
Published: February 2008

We study the relationship between the masses and the geometric properties of central configurations. We prove that, in the planar four-body problem, a convex central configuration is symmetric with respect to one diagonal if and only if the masses of the two particles on the other diagonal are equal. If these two masses are unequal, then the less massive one is closer to the former diagonal. Finally, we extend these results to the case of non-planar central configurations of five particles.
DNA polymerase γ inhibition by vitamin K3 induces mitochondria‐mediated cytotoxicity in human cancer cells
Authors: Sasaki Ryohei , Suzuki Yoko , Yonezawa Yuko , Ota Yosuke , Okamoto Yoshiaki , Demizu Yusuke , Huang Peng , Yoshida Hiromi , Sugimura Kazuro , Mizushina Yoshiyuki
Published: February 2008

Among the vitamin K (VK) compounds, VK3 exhibits distinct cytotoxic activity in cancer cells and is thought to affect redox cycling; however, the underlying mechanisms remain unclear. Here we demonstrate that VK3 selectively inhibits DNA polymerase (pol) γ, the key enzyme responsible for mitochondrial DNA replication and repair. VK3 at 30 µM inhibited pol γ by more than 80%, caused impairment of mitochondrial DNA replication and repair, and induced a significant increase in reactive oxygen species (ROS), leading to apoptosis. At a lower concentration (3 µM), VK3 did not cause a significant increase in ROS, but was able to effectively inhibit cell proliferation, which could be reversed by supplementing glycolytic substrates. The cytotoxic action of VK3 was independent of p53 tumor suppressor gene status. Interestingly, VK3 only inhibited pol γ but did not affect other pol including human pol α, pol β, pol δ, and pol ɛ. VK1 and VK2 exhibited no inhibitory effect on any of the pol tested. These data together suggest that the inhibition of pol γ by VK3 is relatively specific, and that this compound seems to exert its anticancer activity by two possible mechanisms in a concentration‐dependent manner: (1) induction of ROS‐mediated cell death at high concentrations; and (2) inhibition of cell proliferation at lower concentrations likely through the suppression of mitochondrial respiratory function. These findings may explain various cytotoxic actions induced by VK3, and may pave the way for the further use of VK3. (Cancer Sci 2008; 99: 1040–1048)
B‐1 lymphocytes increase metastatic behavior of melanoma cells through the extracellular signal‐regulated kinase pathway
Authors: Pérez Elizabeth Cristina , Machado Joel , Aliperti Fabiana , Freymüller Edna , Mariano Mario , Lopes José Daniel
Published: February 2008

Increasing evidence indicates that tumors require a constant influx of myelomonocytic cells to support their malignant behavior. This is caused by tumor‐derived factors, which recruit and induce functional differentiation of myelomonocytic cells, most of which are macrophages. Although myeloid lineages are the classical precursors of macrophages, B‐lymphoid lineages such as B‐1 cells, a subset of B‐lymphocytes found predominantly in pleural and peritoneal cavities, are also able to migrate to inflammatory sites and differentiate into mononuclear phagocytes exhibiting macrophage‐like phenotypes. Here we examined the interplay of B‐1 cells and tumor cells, and checked whether this interaction provides signals to influence melanoma cells metastases. Using in vitro coculture experiments we showed that B16, a murine melanoma cell line, and B‐1 cells physically interact. Moreover, interaction of B16 with B‐1 cells leads to up‐regulation of metastasis‐related gene expression (MMP‐9 and CXCR‐4), increasing its metastatic potential, as revealed by experimental metastases assays in vivo. We also provide evidence that B16 cells exhibit markedly up‐regulated phosphorylation of the extracellular signal–regulated kinase (ERK) when cocultured with B‐1 cells. Inhibition of ERK phosphorylation induced by B‐1 cells with inhibitors of MEK1/2 strongly suppressed the induction of MMP‐9 and CXCR‐4 mRNA expression and impaired the increased metastatic behavior of B16. In addition, constitutive levels of ERK1/2 phosphorylation in B‐1 cells are necessary for their commitment to affect the metastatic potential of B16 cells. Our findings show for the first time that B‐1 lymphocytes can contribute to tumor cell properties required for invasiveness during metastatic spread. (Cancer Sci 2008; 99: 920–928)
Role of Werner syndrome gene product helicase in carcinogenesis and in resistance to genotoxins by cancer cells
Authors: Futami Kazunobu , Ishikawa Yuichi , Goto Makoto , Furuichi Yasuhiro , Sugimoto Masanobu
Published: February 2008

Werner syndrome (WS) is an autosomal recessive genetic disorder causing premature aging, and WRN has been identified as the causative gene of WS. The product of the WRN gene (WRN) acts as a DNA helicase with exonuclease activity, and data have accumulated showing that the WRN gene strongly participates in carcinogenesis: (1) the normal WRN gene likely participates in the immortalization of B‐lymphoblastoid cell lines through telomeric crisis caused by telomere shortening, (2) a much higher incidence of rare cancers occurs in WS patients than in other kinds of patients, and (3) levels of WRN expressed in virus‐transformed cells and cancer cells are usually markedly up‐regulated and are inversely correlated with the sensitivity of these cells against various genotoxins, including camptothecin. In this paper, we review the events that show a close correlation of the WRN gene and WRN with carcinogenesis and their underlying molecular mechanisms. (Cancer Sci 2008; 99: 843–848)
Cardiopulmonary bypass for surgical correction of congenital heart disease in children with sickle cell disease: a case series
Authors: Harban F. M. J. , Connor P. , Crook R. , Bingham R.
Published: February 2008

We present a series of three children with sickle cell disease aged 3 months, 3 weeks and 18 months, all presenting for cardiac surgery requiring cardiopulmonary bypass. The cardiac lesions were atrioventricular septal defect, transposition of the great arteries and ventricular septal defect, with sickle cell loads of 35%, 11% and 39% respectively at presentation. We calculated that the bypass circuit would provide sufficient volume to decrease sickle cell levels to safe values, so we decided to proceed to bypass without pre‐operative exchange transfusion, and modified the bypass technique so as to avoid the likely stimulants of a sickle cell crisis. Haemoglobin S levels after the start of bypass were significantly lower than before bypass, and remained low throughout the case and into the second postoperative day. By adopting this approach, we feel that we achieved a successful outcome with minimal distress to the children and their families.
Single 270 μg kg−1‐dose rFVIIa vs. standard 90 μg kg−1‐dose rFVIIa and APCC for home treatment of joint bleeds in haemophilia patients with inhibitors: a randomized comparison
Authors: YOUNG G. , SHAFER F. E. , ROJAS P. , SEREMETIS S.
Published: February 2008

Summary. Evidence suggests greater doses of recombinant activated factor VII (rFVIIa; NovoSeven®, Novo Nordisk A/S, Bagsværd, Denmark) than currently administered may result in enhanced haemostasis and convenience for patients with haemophilia A and B with inhibitors. This study evaluated efficacy and safety of rFVIIa and an activated prothrombin complex concentrate (APCC; Factor Eight Inhibitor Bypassing Activity [FEIBA]®, Baxter AG, Vienna, Austria) for controlling joint bleeds in a home‐treatment setting. Patients received each of three treatments in one of six possible sequences: 270 μg kg−1rFVIIa at hour 0 + placebo at hours 3 and 6, 90 μg kg−1rFVIIa at hours 0, 3 and 6, and 75 U kg−1APCC at hour 0. Efficacy was assessed by the requirement for additional haemostatics within 9 h and by a novel global response algorithm. The percentage of rFVIIa 270 μg kg−1group patients requiring additional haemostatics within 9 h (8.3%) was significantly lower than that for the APCC group (36.4%,P = 0.032). The percentage of rFVIIa 90 × 3 μg kg−1group patients requiring such rescue medication (9.1%) was also lower compared to the APCC group. This result approached, but did not reach statistical significance (P = 0.069). Both rFVIIa treatment groups showed similar use of rescue medication (8.3% and 9.1% of episodes for rFVIIa 270 μg kg−1and rFVIIa 90 × 3 μg kg−1groups respectively). No significant differences in treatment response were observed with the global response algorithm (P = 0.173). No safety issues were identified. A single dose of rFVIIa 270 μg kg−1is as safe and effective as rFVIIa 90 × 3 μg kg−1dosing, and may be considered a potentially more effective alternative to APCCs for the management of joint bleeding in this population.
Reliability and construct validity of the compatible MRI scoring system for evaluation of elbows in haemophilic children
Authors: DORIA A. S. , LUNDIN B. , MILLER S. , KILCOYNE R. , DUNN A. , THOMAS S. , RIVARD G. , MOINEDDIN R. , BABYN P.S. ,   EXPERT IMAGING WORKING GROUP OF THE INTERNATIONAL PROPHYLAXIS STUDY GROUP
Published: February 2008

Summary.  We assessed the reliability and construct validity of the Compatible MRI scale for evaluation of elbows, and compared the diagnostic performance of MRI and radiographs for assessment of these joints. Twenty‐nine MR examinations of elbows from 27 boys with haemophilia A and B [age range, 5–17 years (mean, 11.5)] were independently read by four blinded radiologists on two occasions. Three centres participated in the study: (Toronto, n = 24 examinations; Atlanta, n = 3; Cuiaba, n = 2). The number of previous joint bleeds and severity of haemophilia were reference standard measures. The inter‐reader reliability of MRI scores was substantial (ICC = 0.73) for the additive (A)‐scale and excellent (ICC = 0.83) for the progressive (P)‐scale. The intrareader reliability was excellent for both P‐scores (ICC = 0.91) and A‐scores (ICC = 0.93). The total P‐ and A‐scores correlated poorly (r = 0.36) or moderately (r = 0.54), but positively, with clinical‐laboratory measurements. The total MRI scores demonstrated high accuracy for discrimination of presence or absence of arthropathy [P‐scale, area‐under‐the‐curve (AUC) = 0.94 ± 0.05; A‐scale, AUC = 0.89 ± 0.06], as did the soft tissue scores of both scales (P‐scale, AUC = 0.90 ± 0.06; A‐scale, AUC = 0.86 ± 0.06). Areas‐under‐the‐curve used to discriminate severe disease demonstrated high accuracy for both P‐MRI scores (AUC = 0.83 ± 0.09) and A‐MRI scores (AUC = 0.87 ± 0.09), but non‐diagnostic ability to discriminate mild disease. Similar results were noted for radiographic scales. In conclusion, both MRI scales demonstrated substantial to excellent reliability and accuracy for discrimination of presence/absence of arthropathy, and severe/non‐severe disease, but poor to moderate convergent validity for total scores and non‐diagnostic discriminant validity for mild/non‐mild disease. Compared with radiographic scores, MRI scales did not perform better for discrimination of severity of arthropathy.
Congenital FX deficiency combined with other clotting defects or with other abnormalities: a critical evaluation of the literature
Authors: GIROLAMI A. , RUZZON E. , TEZZA F. , SCANDELLARI R. , SCAPIN M. , SCARPARO P.
Published: February 2008

Summary.  The presence of more than one congenital clotting defect in a given patient is a rare event but not an exceptional one. Combined defects of factor X (FX) are very rare because congenital isolated FX deficiency is by itself very rare. A perusal of personal files and of the literature has yielded 12 families with FX deficiency in which an association with another clotting factor deficiency was found. The associated defects were factor VII (FVII) or factor VIII (FVIII) or factor XII (FXII) deficiency. By far the most frequently associated was with FVII. Two forms of this association were found. In the first form there is casual association of both FVII and FX deficiency in the proband with independent recessive segregation of the two defects in other family members. The second form is because of abnormalities in chromosome 13 (deletions, translocations and so on) involving both FX and FVII genes. These genes are known to be very close and located on the long arm of chromosome 13 at about 13q34. In this form the hereditary pattern is autosomal dominant. Isolated FX deficiency and, more frequently, combined FX + FVII deficiency appear also associated with coagulation‐unrelated abnormalities (carotid body tumours, mitral valve prolapse, atrial septal defect, ventricular septal defect, thrombocytopenia absent radius (TAR) syndrome, mental retardation, microcephaly and cleft palate). Diagnosis of a combined clotting defect could be difficult on the basis of global tests. For example, both isolated FX deficiency and combined FX + FVII deficiency yield a prolongation of basal PTT and PT. Only specific assays could allow one to reach the correct diagnosis. In cases of casual association with other defects, it is also important to study family members, as the two defects should segregate independently.
Efficacy of factor VIII/von Willebrand factor concentrate Alphanate® in preventing excessive bleeding during surgery in subjects with von Willebrand disease
Authors: RIVARD G. E. , ALEDORT L. ,   THE ALPHANATE SURGICAL INVESTIGATORS
Published: February 2008

Summary.  The adequacy of perioperative haemostasis with a high‐purity, plasma‐derived factor VIII product containing von Willebrand factor was retrospectively evaluated in 39 patients with type 1, 2 or 3 von Willebrand disease who underwent 61 major or minor surgical or invasive procedures. Overall, 93.5% of the responses to treatment were rated as excellent or good by the physician investigators. These ratings were confirmed by an independent panel of physician referees.
Low‐dose immune tolerance induction for paediatric haemophilia patients with factor VIII inhibitors
Authors: UNUVAR A. , KAVAKLI K. , BAYTAN B. , KAZANCI E. , SAYLI T. , OREN H. , CELKAN T. , GURSEL T.
Published: February 2008

Summary.  The development of an inhibitor against factor VIII (FVIII) is a serious complication in children with haemophilia A. Immune tolerance induction (ITI) therapy is generally considered to be the best approach to eradicate the inhibitor. In this paper, the low‐dose (≤50 IU kg−1 twice or three times weekly with plasma‐derived factor concentrates) ITI regimen used in Turkey is discussed. This regimen was given to 21 haemophilia A patients with high titer inhibitors. The median age at the beginning of ITI was 9 years and exposure days were 25. The median pre‐ITI historical peak inhibitor titer, and inhibitor titer when ITI started were 80 BU (range 6.0–517), 19.2 BU (range 3.6–515), respectively. Complete immune tolerance was defined as the time at which at least two negative inhibitor assays was obtained with no anamnestic response. Our two cases were not reached in follow‐up period. Immune tolerance could be achieved in 5 of 19 (26.3%) patients within a median time of 6 months. Partial tolerance was obtained in 7 patients while treatment failed in spite of significant decreased inhibitor levels in the other patients. A relapse developed in one immune‐tolerized patient, one year later. The level of inhibitor titer at the beginning of ITI (≤10 BU), the pre‐ITI historical peak inhibitor titer (<50 BU), and the time between the first diagnosis inhibitor to starting ITI (<12 months) were main factors in the success (complete or partial tolerance) of ITI. In conclusion, the outcome of low‐dose ITI protocol was not satisfactory in this retrospective study.
Some recent developments regarding arthropathy and inhibitors in haemophilia
Authors: RODRIGUEZ‐MERCHAN E. C.
Published: February 2008

Summary.  In this paper, the most recent developments on arthropathy and inhibitors in haemophilia are reviewed. Firstly, early long‐term prophylaxis is strongly recommended in children with severe haemophilia. Secondly, in joint bleeds not responding to substitution of factor VIII to normal factor VIII levels angiographic embolization might be considered as a promising therapeutic option. Thirdly, recent data indicate disruption of normal development for adolescents with inhibitors. Fourthly, some case reports indicate the benefit of secondary prophylaxis with recombinant factor VIIa (rFVIIa) or factor eight inhibitor bypassing activity (FEIBA) in patients with severe haemophilia A and inhibitors. Finally, surgical procedures in haemophilia patients with factor inhibitors can be accomplished safely and effectively with FEIBA and/or rFVIIa, although the risk of complications is higher than in haemophilia patients without inhibitors.
Light‐chain‐restricted germinal centres in reactive lymphadenitis: report of eight cases
Authors: Nam‐Cha S H , San‐Millán B , Mollejo M , García‐Cosio M , Garijo G , Gomez M , Warnke R A , Jaffe E S , Piris M A
Published: February 2008

Aims:  Light‐chain‐restricted germinal centres are generally associated with the existence of a neoplastic lymphoproliferative disorder. The aim was to present a series of cases with persistent lymph node enlargement that featured some germinal centres showing light chain immunoglobulin restriction.

Methods and results:  A series of six reactive lymphadenitis and two Castleman’s disease cases was analysed by immunohistochemistry, IgH‐polymerase chain reaction (PCR) and microdissected PCR. In all cases some germinal centres contained a population of plasma cells and plasmacytoid germinal centre cells showing light chain immunoglobulin restriction. In three cases the monotypic cells also showed distinct Bcl‐2 expression. Two of the cases showed a predominant IgH rearrangement on a florid polyclonal background and one had an IgH monoclonal rearrangement, as revealed by PCR. Microdissected germinal centre PCR revealed a dominant repeated band in one of three cases and in another case a non‐repeated clonal peak was observed. One of the patients developed a follicular lymphoma, which became evident from a subsequent biopsy.

Conclusions:  These findings may be a manifestation of an underlying disorder in the regulation of the immune response, or an exaggeration of the germinal centre oligoclonal nature. This should be taken into account in the differential diagnosis of follicular hyperplasia.
Sporadic paediatric and adult Burkitt lymphomas share similar phenotypic and genotypic features
Authors: Chuang S‐S , Huang W‐T , Hsieh P‐P , Jung Y‐C , Ye H , Du M‐Q , Lu C‐L , Cho C‐Y , Hsiao S‐C , Hsu Y‐H , Lin K‐J
Published: February 2008

Aims:  To characterize the clinicopathological features of sporadic Burkitt lymphoma (BL).

Methods and results:  A retrospective study of 17 paediatric and 14 adult BLs with history and histopathology review, immunohistochemistry, Epstein–Barr virus (EBV) in situ hybridization (EBER) and fluorescence in situ hybridization. There was no statistically significant difference in gender, frequency of central nervous system (CNS) involvement and leukaemic change at presentation, or frequency of CD10+/Bcl‐2−/Bcl‐6+ (88% versus 86%), Ki67 labelling index, EBER (24% versus 21%), or C‐MYC translocation (100% versus 92%) between paediatric and adult tumours. Correct pretreatment diagnoses were made in 13/17 (76%) paediatric and in 9/14 (64%) adult tumours. Twenty‐eight patients received chemotherapy including 13/16 (81%) paediatric and 3/12 (25%) adult patients with appropriate regimens; 16 (57%) received CNS prophylaxis. The 1‐ and 5‐year overall survival (OS) rates for paediatric patients were 80% and 50%, respectively, whereas 1‐year OS for adults was 15%.

Conclusions:  Sporadic paediatric and adult BLs were phenotypically and genotypically similar. The significant prognosticators were age (P = 0.001), with or without CNS prophylaxis (P = 0.004), and CNS involvement (P = 0.008) and leukaemic change (P = 0.019) in disease course. The poor outcome in adult patients might be related to incorrect diagnosis and inappropriate treatment.
Prognosis in human melanoma: PAR‐1 expression is superior to other coagulation components and VEGF
Authors: Depasquale I , Thompson W D
Published: February 2008

Aims: Two hundred and four accessible cases of malignant melanoma from the Grampian region of Scotland, collected over a period of 4 years, with minimum follow‐up of 2 years, were studied for coagulation factors and vascular endothelial growth factor (VEGF) expression as potential prognostic markers. The aim was to allow comparison with previous work using microvessel density on the same cases.

Methods and results: Immunohistochemistry for VEGF, tissue factor (TF), fibrin and protease‐activated thrombin receptor (PAR)‐1 in 204 cases of melanoma was performed, and intensity of expression scored. Chalkley microvessel counts (MVD) were obtained for the tumour edge. TF expression and presence of fibrin correlated well with Breslow thickness and ulceration, reaching statistical significance, but surprisingly not for metastatic recurrence. Fibrin was variably present in over half the cases, located at the invasive edge, ulcerated surface and between tumour cell surfaces. In a few cases fibrin was within tumour cells, typically co‐located with melanin and confirmed by electron microscopy. In contrast, immunohistochemistry for PAR‐1 produced statistically significant results, correlating expression with Breslow thickness (P ≤ 0.001), ulceration (P = 0.001) and recurrence (P ≤ 0.005). Intensity of reactivity of VEGF correlated significantly with Breslow thickness, Clark level, ulceration and MVD, but not for metastatic recurrence.

Conclusions: It appears paradoxical that VEGF expression is not more predictive of recurrence, but even low expression may be sufficient for tumour angiogenesis and other factors must govern tumour aggression. Antagonism of VEGF may still prove a successful adjunct in future therapeutic trials. Both MVD and PAR‐1 can be used as adjuncts to Breslow thickness and ulceration as prognostic indicators for melanoma, as they appear to give independent information for all thicknesses. PAR‐1 expression is the best antibody marker of recurrence risk from those studied. It remains to be seen whether this methodology can predict response to novel antiangiogenic therapies currently entering trial.
Regional and environmental effects on the species richness of mammal assemblages
Authors: Hortal Joaquín , Rodríguez Jesús , Nieto‐Díaz Manuel , Lobo Jorge M.
Published: February 2008

Aim  Variation in species richness has been related to (1) environmental conditions (water, energy and habitat characteristics) and (2) regional differences (contingent historical events and regional particularities that result in differences between regional faunas acting at broad extents). Whereas climatic factors have been widely studied, the effects of regional differences are less often quantified. This work aims to characterize global trends in the species richness of mammal assemblages with respect to both current and historical influences.

Location  All terrestrial biogeographical realms except Antarctica.

Methods  Species richness in checklists from 224 sites distributed worldwide were investigated by partitioning the variation between a general set of habitat/climate factors, biogeographical regions, and their overlaps. Additional analyses studied the specific overlaps of region, water and energy. Data were also divided according to area to determine if the strength of these effects varies according to the size of sites.

Results  Environmental effects explained 38% of richness variation across all sites, whereas environmentally independent regional effects explained 11% and the overlap between region and environment explained 13%. Results were similar when only larger sites (between 1000 km2 and 10,000 km2) were considered. However, the importance of the overlap between region and all environmental variables was greater in smaller sites (between 100 km2 and 1000 km2). In contrast, the specific importance of water and energy variables and their overlap with region was greater in larger sites. The strength of the independent effect of region remained almost invariant regardless of the size of the sites studied.

Main conclusions  The relationship between species richness and climate varies with scale and among regions. Although environmental variables are the strongest correlates of richness, the unique history and physiographic characteristics of a region produce differences between the richness of mammal assemblages and their response to environmental gradients. The importance of environmental variables varies with scale: climatic gradients are more important at coarse grain (larger sites), possibly as a result of their effects on species ranges, whereas habitat type is more important at the smaller sites, where the importance of ecological interactions increases. Therefore, regional differences and the scale at which richness is measured should be taken into account when evaluating species richness–energy hypotheses.
Burning seeds: germinative response to heat treatments in relation to resprouting ability
Authors: Paula S. , Pausas J. G.
Published: February 2008

In Mediterranean fire‐prone ecosystems, plant species persist and regenerate after fire by resprouting, by recruiting new individuals from a seed bank (post‐fire seeding), or by both resprouting and post‐fire seeding. Since species with resprouting ability are already able to persist in fire‐prone ecosystems, we hypothesize that they have been subjected to lower evolutionary pressure to acquire traits allowing or enhancing post‐fire recruitment. Consequently, we predict that the germination of non‐resprouters is more likely to be increased or at least unaffected by heat than the germination of resprouters.

To test this hypothesis we compiled published experiments carried out in Mediterranean Basin species where seeds were exposed to different heat treatments. We compared the probability of heat‐tolerant germination (i.e. heated seeds had greater or equal germination than the control), the probability of heat‐stimulated germination (i.e. heated seeds had greater germination than the control) and the stimulation magnitude (differences in proportion of germination of the heated seeds in relation to the untreated seeds, for heat‐stimulated treatments) between resprouters and non‐resprouters.

Non‐resprouters showed higher probability of heat‐tolerance, higher probability of heat‐stimulation and higher stimulation magnitude even when phylogenetic relatedness was considered. Differences between life‐forms and post‐fire seeding ability do not explain this pattern.

Non‐resprouters appear to have a greater capacity to both (i) persist after fire by means of recruiting (greater heat‐tolerance) and (ii) increase their population after fire (greater heat‐stimulated germination), than resprouters.

Synthesis. Our results contribute to understanding the factors that condition the evolution of fire‐persistence plant traits and support the hypothesis that resprouting and post‐fire recruitment are negatively associated in Mediterranean Basin flora.
Raven's Coloured Progressive Matrices as a measure of cognitive functioning in Cerebral Palsy
Authors: Pueyo R. , Junqué C. , Vendrell P. , Narberhaus A. , Segarra D.
Published: February 2008

Background  Cognitive dysfunction is frequent in Cerebral Palsy (CP). CP motor impairment and associated speech deficits often hinder cognitive assessment, with the result being that not all CP studies consider cognitive dysfunction. Raven's Coloured Progressive Matrices is a simple, rapid test which can be used in persons with severe motor impairment and speech limitations. We studied whether this test can offer a reliable measure of cognitive functioning in CP.

Method  Visuoperceptual, language, memory and frontal lobe functions were evaluated in 30 participants with severe motor impaired CP and a variety of speech difficulties. The relationship between Raven's Coloured Progressive Matrices and a variety of tests was analysed.

Results  Raven's Coloured Progressive Matrices performance was associated with visuoperceptual, language, visual and verbal memory but not with frontal functions. Receptive vocabulary and visuospatial measures were the best predictors of Raven's Coloured Progressive Matrices raw scores.

Conclusions  Raven's Coloured Progressive Matrices is a fast, easy‐to‐administer test able to obtain a measure related with linguistic, visuoperceptual, and memory cognitive functioning in persons with CP despite their motor and speech disorders.
Multiple sclerosis in Gypsies from southern Spain: prevalence, mitochondrial DNA haplogroups and HLA class II association
Authors: Fernández O. , Fernández V. , Martinez‐Cabrera V. , Mayorga C. , Alonso A. , León A. , Arnal C. , Hens M. , Luque G. , De Ramón E. , Caballero A. , Leyva L.
Published: February 2008

Occasional reports have mentioned the prevalence of multiple sclerosis (MS) among Gypsies, and no studies have examined to date the prevalence of MS or human leukocyte antigen (HLA) genetics associations in the Spanish Gypsy population. We decided to study the prevalence, mitochondrial DNA (mtDNA) haplogroups and HLA class II distribution among gypsies with MS in southern Spain. We searched for Gypsy MS patients and studied HLA class II alleles by polymerase chain reaction with sequence‐specific oligonucleotide (PCR/SSO) probe hybridization or sequence‐specific primers amplification. An additional study of the mtDNA haplogroups by sequencing of the hypervariable segments of the control region was also performed to provide details of their ethnic origin. Estimated prevalence of MS in the Gypsy population in Malaga was 52/100,000. No significant differences were found in mtDNA between Gypsy MS patients and Gypsy controls. DRB1*1501, DQB1*0602 and DQB1*0608 alleles were the only positive HLA association with MS. The Gypsies in our series have the same anthropological origin as other European gypsy groups, as shown by mtDNA haplogroups. Although interpreted with great caution because of the small sample size, we found that the prevalence of MS in Gypsies in Malaga is not as low as that in Central Europe, although it is significantly less than that found in Caucasians from Spain (75–79/100,000). DQB1*0602 was the strongest positive association found with Gypsy MS patients, and DRB1*1501‐DQB1*0602 was the most frequent haplotype in this group.
Clostridium difficile colitis in lung transplantation
Authors: Gunderson C.C. , Gupta M.R. , Lopez F. , Lombard G.A. , LaPlace S.G. , Taylor D.E. , Dhillon G.S. , Valentine V.G.
Published: February 2008

Purpose. Clostridium difficile colitis (CDC) is the most common nosocomial infection of the gastrointestinal tract in patients with recent antibiotic use or hospitalization. Lung transplant recipients receive aggressive antimicrobial therapy postoperatively for treatment and prophylaxis of respiratory infections. This report describes the epidemiology of CDC in lung recipients from a single center and explores possible associations with bronchiolitis obliterans syndrome (BOS), a surrogate marker of chronic rejection.

Methods. Patients were divided into those with confirmed disease (CDC+) and those without disease (CDC−) based on positive C. difficile toxin assay. Because of a bimodal distribution in the time to develop CDC, the early postoperative CDC+ group was analyzed separately from the late postoperative CDC+ cohort with respect to BOS development.

Results. Between 1990 and 2005, 202 consecutive patients underwent 208 lung transplantation procedures. Of these, 15 lung recipients developed 23 episodes of CDC with a median follow‐up period of 2.7 years (range, 0–13.6). All patients with confirmed disease had at least 1 of the following 3 risk factors: recent antibiotic use, recent hospitalization, or augmentation of steroid dosage. Of the early CDC+ patients, 100% developed BOS, but only 52% of the late CDC+ patients developed BOS, either preceding or following infection.

Conclusion. CDC developed in 7.4% of lung transplant patients with identified risk factors, yielding a cumulative incidence of 14.7%. The statistical association of BOS development in early CDC+ patients suggests a relationship between early infections and future chronic lung rejection.
Molecular Detection of Colletotrichum lindemuthianum by Duplex PCR
Authors: Wang W. , Tang J. H. , Wang Y. C.
Published: February 2008

A duplex PCR technique was developed to detect the pathogenic fungus Colletotrichum lindemuthianum infection in the tissues of common bean. Based on the differences of 24 internal transcribed spacer, DNA sequences of Colletotrichum spp. retrieved from GeneBank database, one pair of specific primers of CY1/CY2 (CY1: 5′‐CTT TGT GAA CAT ACC TAA CC‐3′; CY2: 5′‐GGT TTT ACG GCA GGA GTG‐3′), was designed. The CY1/CY2 primers amplified a single PCR product of 442 bp only from C. lindemuthianum and Colletotrichum orbiculare, not from any other tested species. By using random amplification of polymorphic DNA technique, a product closely associated with C. lindemuthianum was generated. This product was cloned, sequenced and used for designing a species‐specific primers of CD1/CD2 (CD1: 5′‐ACC TGG ACA CAT AAG TCA AAG‐3′; CD2: 5′‐CAA CAA TGC CAG TAT CAG AG‐3′). The CD1/CD2 primers could distinguish C. lindemuthianum from C. orbiculare by a 638 bp PCR band. A duplex PCR method, combining both primers of CY1/CY2 and CD1/CD2, was used to detect C. lindemuthianum infection. The sensitivity of the detection with this PCR method was 1 pg of pure genomic DNA from the pathogen. Therefore, the PCR‐based methods could be used for accurate and rapid detection of C. lindemuthianum from common bean.
SYSTEMIC ADMINISTRATION OF Zn2+DURING THE REPERFUSION PHASE OF TRANSIENT CEREBRAL ISCHAEMIA PROTECTS RAT HIPPOCAMPUS AGAINST IRON‐CATALYSED POSTISCHAEMIC INJURY
Authors: Helal Gouda K
Published: February 2008

The aim of the present study was to test the protective role of intravenous Zn2+against iron‐catalysed reperfusion injury in the hippocampus of ischaemic rats.

One hundred adult male Wistar albino rats were randomly divided into five groups. Rats in the first group were subjected to surgery (sham operation) without induction of cerebral ischaemia and injected with normal saline (i.v.). The second group of sham‐operated rats were injected with 6 mg/kg, i.v., ZnCl2. In the third group, rats were subjected to cerebral ischaemia for 60 min. Animals in the fourth group were subjected to cerebral ischaemia for 60 min followed by 8 h reperfusion. In the fifth group, rats were subjected to cerebral ischaemia for 60 min, followed by 8 h reperfusion with injection of a single dose of ZnCl2(6 mg/kg, i.v.) during the first 5 min of the reperfusion period. After reperfusion, animals were killed, their brains were dissected out on ice and the two hippocampi from each animal were isolated and analysed.

Cerebral ischaemia induced an increase in the iron content, lipidic peroxidation, apoptosis and metallothionein (MT) in the hippocampus. These effects were significantly increased in the hippocampus of ischaemic rats subjected to 8 h reperfusion compared with ischaemic non‐reperfused rats. Intravenous administration of ZnCl2decreased the accumulation of iron, lipidic peroxidation and apoptosis produced by reperfusion, but increased the level of MT.

Data from the present study suggest that, after 1 h ischaemia, there is an increase in the permeability of the blood–brain barrier and this allows penetration of i.v. injected ZnCl2, which can induce expression of brain MT, increase the anti‐oxidant capacity and diminish iron‐catalysed lipid peroxidation and apoptosis. This may give new insights as to how to improve the outcome for stroke patients.
DIAPHRAGM MUSCLE STRIP PREPARATION FOR EVALUATION OF GENE THERAPIES IN mdx MICE
Authors: Faulkner John A , Ng Rainer , Davis Carol S , Li Sheng , Chamberlain Jeffrey S
Published: February 2008

Duchenne muscular dystrophy (DMD), a severe muscle wasting disease of young boys with an incidence of one in every 3000, results from a mutation in the gene that encodes dystrophin. The absence of dystrophin expression in skeletal muscles and heart results in the degeneration of muscle fibres and, consequently, severe muscle weakness and wasting. The mdx mouse discovered in 1984, with some adjustments for differences, has proven to be an invaluable model for scientific investigations of dystrophy.

The development of the diaphagm strip preparation provided an ideal experimental model for investigations of skeletal muscle impairments in structure and function induced by interactions of disease‐ and age‐related factors. Unlike the limb muscles of the mdx mouse, which show adaptive changes in structure and function, the diaphragm strip preparation reflects accurately the deterioration in muscle structure and function observed in boys with DMD.

The advent of sophisticated servo motors and force transducers interfaced with state‐of‐the‐art software packages to drive complex experimental designs during the 1990s greatly enhanced the capability of the mdx mouse and the diaphragm strip preparation to evaluate more accurately the impact of the disease on the structure–function relationships throughout the life span of the mouse.

Finally, during the 1990s and through the early years of the 21st century, many promising, sophisticated genetic techniques have been designed to ameliorate the devastating impact of muscular dystrophy on the structure and function of skeletal muscles. During this period of rapid development of promising genetic therapies, the combination of the mdx mouse and the diaphragm strip preparation has provided an ideal model for the evaluation of the success, or failure, of these genetic techniques to improve dystrophic muscle structure, function or both. With the 2 year life span of the mdx mouse, the impact of age‐related effects can be studied in this model.
Fire season effects on the recruitment of non‐sprouting serotinous Proteaceae in the eastern (bimodal rainfall) fynbos biome, South Africa
Authors: HEELEMANN STEFFEN , PROCHEŞ ŞERBAN , REBELO ANTHONY G. , Van WILGEN BRIAN W. , POREMBSKI STEFAN , COWLING RICHARD M.
Published: February 2008

Abstract  Research in Mediterranean‐climate shrublands in both South Africa and Australia shows that recruitment of proteoid shrubs (non‐sprouting, serotinous Proteaceae) is best after warm‐season (summer and autumn) fires and worst after cool‐season (winter and spring) ones. This pattern has been attributed to post‐dispersal seed attrition as well as size of pre‐dispersal seed reserves. Here we investigate patterns of post‐fire recruitment for four proteoid species in the eastern part of South Africa's fynbos biome, which has a bimodal (spring and autumn) rainfall regime. Despite the lack of significant differences in recruitment between cool‐ and warm‐season burns, we find some evidence for favourable recruitment periods following fires in spring and autumn, immediately before, and coinciding with, the bimodal rainfall peaks. This suggests that enhanced recruitment is associated with conditions of high soil moisture immediately after the fire, and that rapid germination may minimize post‐dispersal seed attrition. In two of the species, we also find a shift from peak flowering in winter and spring in the Mediterranean‐climate part of the fynbos biome, to summer and autumn flowering in the eastern part. Because these two species are only weakly serotinous, warm‐season flowering would result in maximal seed banks in spring, which could explain the spring recruitment peak, but not the autumn one. We conclude that eastern recruitment patterns differ significantly from those observed in the western and central parts of the biome, and that fire management protocols for the east, which are currently based on data and experience from the winter‐rainfall fynbos biome, need to be adjusted accordingly. Fire managers in the eastern fynbos biome should be less constrained by requirements to burn within a narrow seasonal range, and should therefore be in a better position to apply the required management burns.
Changes in understorey plant species richness following logging and prescribed burning in shrubby dry sclerophyll forests of south‐eastern Australia
Authors: PENMAN TRENT D. , BINNS DOUG L. , SHIELS ROY J. , ALLEN RUTH M. , KAVANAGH RODNEY P.
Published: February 2008

Abstract  The impacts of prescribed burning and timber harvesting on species diversity have been the subject of considerable debate. The temporal and spatial scale of these disturbances often presents major limitations to many studies. Here we present the medium‐term results of a planned long‐term study examining the impacts of logging and prescribed burning on the understorey floristic richness in shrubby dry sclerophyll forest in the south‐east of New South Wales, Australia. Generalized estimating equations were used to model the effect of environmental factors and disturbance variables on species richness at the coupe (∼30 ha) and plot (∼0.01 ha) scale. At the plot scale, fire effects on separate components of the vegetation were broadly consistent with other studies, with frequent fire resulting in a relative increase of species richness for species less than 1 m in height and a decline of larger species taller than this height. At the coupe scale, there was no decline in richness of larger shrub species, possibly owing to the spatial heterogeneity of fire frequency at this scale. Logging resulted in significantly greater species richness in the shrub layer, but had no significant effect on species richness in the ground layer. During the study period, there was a general decline in plant species richness at both coupe and plot scales which occurred independently of imposed management regimes. This is thought to be related to a natural succession following wildfire, and may be due to the absence of high‐intensity fire in the study area since 1973, or to an effect related to season of burning.