A novel HLA-A allele, HLA-A*02:544

The novel allele HLA-A*02:544 has two nucleotide changes from its most closely related allele, HLA-A*02:148. Firstly at nucleotide 255 where C → T (codon 60 GAC → GAT), resulting in a non-coding change as GAC and GAT both code for the same amino acid aspartic acid. Secondly at nucleotide 368 where T → G (codon 98 TTT → TGT) resulting in a coding change, 98 phenylalanine is changed to cysteine.

Design of FeBi nanoparticles for imaging applications

A variety of imaging technologies are now routinely used in the medical field, their use being continuously enlarged through the development of contrast agents. Recently nanoparticles (NPs) proved efficient to improve imaging in vivo by increasing contrast and targeting capabilities. The current trend is now focused on the development of dual contrast agents combining two or more functionalities on the same NP. Motivated by this new challenge we developed FeBi NPs as new nanomaterials with potential application as a contrast agent for MRI and CT imaging. In addition to the well-known use of iron in the development MRI contrast agents, we chose Bi as a CT imaging agent rather than the more documented gold, because it possesses a larger X-ray attenuation coefficient and is much less expensive. Two sets of NPs, with sizes around 150 nm and 14 nm, were synthesized using organometallic approaches. In both cases, the NPs are spherical, and contain distinct domains of Fe and Bi, with the surface being enriched with Fe, and a hydrophobic coating. This coating differs from one sample to the other: the surfaces of the 150 nm large NPs are coated by amine ligands, while those of the 14 nm large NPs are coated by a mixture of an amine and its hydrochloride salt. Exchange of the surface ligands to afford water soluble NPs has been attempted. We show that only the larger NPs could be functionalized with water soluble ligands, which is in agreement with the lability of their initial surface coating. Colloidal aqueous solutions of FeBi NPs with glycoPEG ligands have been obtained.

Safe and efficient local gene delivery into skeletal muscle via a combination of Pluronic L64 and modified electrotransfer

Efficient DNA electrotransfer into muscles can be achieved by combining two types of electronic pulses sequentially: short high-voltage (HV) pulse for the cell electropermeabilization and long low-voltage (LV) pulse for the DNA electrophoresis into cells. However, the voltages currently applied can still induce histological and functional damages to tissues. Pluronic L64 has been considered as a molecule possessing cell membrane-disturbing ability. For these reasons, we hope that L64 can be used as a substitute for the HV pulse in cell membrane permeabilization, and a safe LV pulse may still keep the ability to drive plasmid DNA across the permeabilized membrane. In this work, we optimized the electrotransfer parameters to establish a safe and efficient procedure using a clinically applied instrument, and found out that the critical condition for a successful combination of electrotransfer with L64 was that the injection of plasmid/L64 mixture should be applied 1 h before the electrotransfer. In addition, we revealed that the combined procedure could not efficiently transfer plasmid into solid tumor because the uncompressed plasmid may rapidly permeate the leaky tumor vessels and flow away. Altogether, the results demonstrate that the combined procedure has the potential for plasmid-based gene therapy through safe and efficient local gene delivery into skeletal muscles.

Fusarium sp. infection in a patient with Acute Lymphoblastic Leukaemia

In the past two decades, Fusarium species have been increasingly recognized as serious pathogens in immunocompromised patients. The outcome of fusariosis in the context of severe persistent neutropaenia has been almost universally fatal. The treatment of fusariosis in immunocompromised patients remains a challenge and the prognosis of systemic fusariosis in this population remains poor. This report presents a case of fatal fusariosis in a 37- year-old patient who was diagnosed with precursor-B cell Acute Lymphoblastic Leukaemia (ALL).

Magnolol, a major bioactive constituent of the bark of Magnolia officinalis, exerts antiepileptic effects via the GABA/benzodiazepine receptor complex in mice

BACKGROUND AND PURPOSE

The aim of this study was to evaluate the anti-convulsant effects of magnolol (6, 6', 7, 12-tetramethoxy-2, 2'-dimethyl-1-β-berbaman, C18H18O2) and the mechanisms involved.

EXPERIMENTAL APPROACH

Mice were treated with magnolol (20, 40 and 80 mg·kg(-1)) 30 min before injection with pentylenetetrazol (PTZ, 60 mg·kg(-1), i.p.). The anti-seizure effects of magnolol were analysed using seizure models of behaviour, EEG and in vitro electrophysiology and c-Fos expression in the hippocampus and cortex.

KEY RESULTS

Magnolol at doses of 40 and 80 mg·kg(-1) significantly delayed the onset of myoclonic jerks and generalized clonic seizures, and decreased the seizure stage and mortality compared with those of the vehicle-treated animals. EEG recordings showed that magnolol (40 and 80 mg·kg(-1)) prolonged the latency of seizure onset and decreased the number of seizure spikes. The anti-epileptic effect of magnolol was reversed by the GABA(A)/benzodiazepine receptor antagonist flumazenil. Pretreatment with flumazenil decreased the effects of magnolol on prolongation of seizure latency and decline of seizure stage. In a Mg(2+)-free model of epileptiform activity, using multi-electrode array recordings in mouse hippocampal slices, magnolol decreased spontaneous epileptiform discharges. Magnolol also significantly decreased seizure-induced Fos immunoreactivity in the piriform cortex, dentate gyrus and hippocampal area CA1. These effects were attenuated by pretreatment with flumazenil.

CONCLUSIONS AND IMPLICATIONS

These findings indicate that the inhibitory effects of magnolol on epileptiform activity were mediated by the GABA(A) /benzodiazepine receptor complex.

Ear size as a predictor of chronological age

It is generally observed that older people have bigger ears and noses. Cartilage is known to alter in structure with age. We conducted a cross sectional study to verify the trend between age and the size of two cartilaginous structures, ear and nose. A total of 100 young individuals were compared to older individuals with respect to their ear and nose sizes. We found that the greatest correlation coefficient of age was with ear circumference, and the linear regression equation being: Ear circumference = 88.1 + (0.51 x subject's age). Except for the ear tragus, which correlated insignificantly with age, anatomical variables of the ear had higher correlation with age than anatomical variables of the nose. This study supports the view that as people age, their ears get larger, particularly the ear circumference, which increases on average 0.51 mm per year. This enlargement is likely associated with aging changes of collagen. The knowledge from this study allows us to calculate the age of an individual based on ear size: Subject's age = 1.96 x (Ear circumference in millimeters - 88.1).

The retinal "lozenge" or "dull macular reflex" in Alport syndrome may be associated with a severe retinopathy and early-onset renal failure

BACKGROUND AND AIMS

Alport syndrome is an inherited disease with renal failure, and often a hearing loss, lenticonus and dot-and-fleck retinopathy. A retinal "lozenge" or "dull macular reflex" has been described in some patients. This study determined the prevalence and significance of this sign.

METHODS

Twenty-three patients from 14 families with X linked Alport syndrome and seven from four families with autosomal recessive disease underwent slit-lamp biomicroscopy for lenticonus, direct and indirect ophthalmoscopy, and photography for the retinopathy.

RESULTS

The lozenge was present in five males (38%) but no females with X linked Alport syndrome, as well as one individual with recessive disease (1/7, 14%). It resulted from the sharp demarcation between the normal fovea and a perifoveal annnulus of confluent dots and flecks that were obvious with magnification of retinal photographs. The lozenge was first noted in adolescence and was always associated with early-onset renal failure, hearing loss and lenticonus.

CONCLUSION

Clinicians must be aware that the "lozenge" or "dull macular reflex" described in Alport syndrome is not a normal variant but reflects a severe, almost confluent perimacular dot and fleck retinopathy. This sign is useful diagnostically and also prognostically, since it is associated with early-onset renal failure.

The design, characteristics and predictors of mortality in the North of England Cellulitis Treatment Assessment (NECTA)

AIMS

Cellulitis is a common cause of acute medical admissions in UK hospitals. The factors that determine susceptibility to an acute admission or to mortality following hospital admission are poorly defined.

METHODS

We studied a retrospective cohort of 568 patients with a diagnosis of cellulitis between 1 January 2001 and 31 December 2003 in the north-east of England to see whether we could determine these factors. We collected data on the factors that were associated with acute hospital admissions and survival. We used a primary end-point of deaths within 1 year of admission for cellulitis.

RESULTS

The characteristics that identified patients at high risk of mortality were present in 39.9% of the cohort studied. The four most common of these characteristics were lower limb oedema 30.1% (95% CI: -26.0 to 34.1), ulceration 24% (95% CI: -20.2 to 27.8), previous myocardial infarction (MI) 19.9% (95% CI: -16.3 to 23.4) and blunt injury 18.7% (95% CI: -15.3 to 22.2). Significant predictors of mortality were: patient's age (p < 0.001), presence of penetrating injury (p < 0.001), previous MI (p < 0.001), presence of liver disease (p = 0.003), presence of lower limb oedema (p = 0.01) and long-term use of drugs that caused sodium and water retention (p < 0.001). Treatment with i.v. flucloxacillin was found to be a significant predictor of survival (odds ratio = 3.43, z =3.42. p < 0.001) at 360 days.

CONCLUSION

Our results show that cellulitis as a cause of an acute medical admission may present with a variety of clinical features. Some of these clinical features can be used to predict mortality within 360 days of an acute hospital admission.

The effect of the major components of Salvia Miltiorrhiza Bunge on bone marrow cells

Salvia Miltiorrhiza Bunge (SMB), a traditional Chinese medicinal herb, has been alleged to support bone healing. However, the effects of the isolated major components of SMB on osseous cells and their corresponding effective doses are still unclear. In the present study, the effects of three components of SMB, including tanshinone IIA (Ts), salvianolic acid B (salB) and protocatechuic aldehyde (Pca), on mesenchymal bone marrow cells with the potential for osteoblastic differentiation were investigated. Various concentrations of Ts, salB and Pca were added to a rat bone marrow cell culture. The total metabolic activity and differentiation of bone marrow cells were evaluated by a metabolic assay and alkaline phosphatase (ALP) activity, respectively. The morphology and number of cells was observed by phase contrast microscopy and fluorescent microscopy after propidium iodide staining, respectively. Ts suppressed the growth and differentiation of bone precursor cells. SalB exhibited a biphasic effect: the high concentration of 160 microg/mL significantly depressed the population of bone marrow cells, however, lower concentrations (3-80 microg/mL) enhanced the total metabolic activity and their ALP expression. Pca suppressed the bone marrow cell population in a dose-dependent manner. Therefore, SalB has the potential to ameliorate bone healing by stimulating both the total metabolic activity and ALP activity of osteoblastic cells. Aqueous extracts, which preferably contain salB over Pca and are free of Ts therefore are recommended for bone formation.

Prospective prediction of spontaneous but not recurrent autoimmune diabetes in the non-obese diabetic mouse

AIMS/HYPOTHESIS

Type 1 diabetes is a T cell-mediated autoimmune disease with a clinically silent prodrome, during which prediction and treatment of disease are theoretically possible. Using retrospective analysis, spontaneous disease in the non-obese diabetic (NOD) mouse has been correlated with islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP)-reactive CD8+ T cells in the peripheral blood. In this study, we determined prospectively whether IGRP-reactive T cells in peripheral blood could predict disease occurrence. Since recurrent autoimmunity is an important contributor to transplant failure, we also determined whether failure of islet grafts (syngeneic and allogeneic) could be predicted by the presence of circulating autoreactive T cells.

MATERIALS AND METHODS

Peripheral blood samples were taken weekly from female NOD mice between the ages of 8 and 30 weeks and from NOD mice transplanted with NODscid islets. Peripheral blood cells and islet grafts were analysed for the presence of IGRP-reactive CD8+ T cells by flow cytometry.

RESULTS

Prospective analysis of peripheral blood IGRP-reactive T cells in the prediabetic period predicted disease development with a sensitivity of 100% and a specificity of 60%, resulting in positive and negative predictive values of 85 and 100%, respectively. Significant proportions of IGRP-reactive T cells were found in the grafts, but not in peripheral blood of NOD mice undergoing syngeneic and allogeneic rejection.

CONCLUSIONS/INTERPRETATION

The occurrence of spontaneous diabetes can be predicted prospectively by measuring peripheral blood autoreactive T cells. Rejection of syngeneic or allogeneic islets is associated with large populations of autoreactive CD8+ T cells within islets, suggesting that immunodominant autoreactive T cells during the prediabetic period are also responsible for autoimmune graft rejection.

A non-invasive system for assessment of aortic stiffness in clinical practice

Previously aortic stiffness is frequently assessed through pulse pressure and pulse wave velocity (PWV) measurements. However, these methods need aortic pressure obtained by catheterization. A new model has been developed to rapidly determine the aortic pressure profile and simultaneously calculate aortic stiffness. Comparison between the aortic pressure result obtained from this and catheterization data demonstrates good agreement, while this method is non-invasive. This totally non-invasive method should be useful in assessing arteriosclerotic disease in clinical setting.

Establishment and comprehensive analysis of a new human transformed follicular lymphoma B cell line, Tat-1

A spontaneously EBV transformed follicular lymphoma (FL) cell line, Tat-1, was established from the lymph node biopsy specimen of a patient with B cell FL, grade 1 in transformation to high grade disease. Tat-1 cells expressed lymphoid markers and developed tumor masses in immunodeficient mice. Bcl-2, Bcl-X(L), Bax and p53 protein expression was revealed by Western blotting. Flow cytometric analysis confirmed P-gp expression. Cytogenetically, the Tat-1 cell line showed identical chromosomal alterations to that of the initial biopsy specimen, among which the most notable were the t(14;18) typical of FL and additional abnormalities involving chromosomes 1, 8 and 13. Multicolor FISH analysis delineated all abnormalities, including a t(1p;8q), a der(8)(8q24::14q32::18q21) and a der(13)(13q32::8q24::14q32::18q21). Further FISH investigations using a locus-specific probe cocktail containing c-myc, IgH and bcl-2 revealed fusion of these three loci on the derivatives 8 and 13, in addition to the derivative 14 IgH/bcl-2 fusion and an extra copy of c-myc on derivative chromosome 1. These results demonstrate an additional example of the deregulation of bcl-2 and c-myc expression through recombination with a single IgH enhancer region. The unusual molecular features of the Tat-1 cell line render it a unique tool for studies focused on cytogenetic alterations, expression of multidrug resistance phenotype and expression of anti-apoptotic proteins in FL.

Detection of dengue viral RNA in Aedes aegypti (Diptera: Culicidae) exposed to sticky lures using reverse-transcriptase polymerase chain reaction

Active surveillance for dengue (DEN) virus infected mosquitoes can be an effective way to predict the risk of dengue infection in a given area. However, doing so may pose logistical problems if mosquitoes must be kept alive or frozen fresh to detect DEN virus. In an attempt to simplify mosquito processing, we evaluated the usefulness of a sticky lure and a seminested reverse-transcriptase polymerase chain reaction assay (RT-PCR) for detecting DEN virus RNA under laboratory conditions using experimentally infected Aedes aegypti (L.) mosquitoes. In the first experiment, 40 male mosquitoes were inoculated with 0.13 microl of a 10(4) pfu/ml DEN-2 stock solution. After a 7-d incubation period, the mosquitoes were applied to the sticky lure and kept at room temperatures of 23-30 degrees C. Following 7, 10, 14, and 28 d application, 10 mosquitoes each were removed from the lure, pooled, and assayed for virus. DEN virus nucleic acid was clearly detectable in all pools up to 28 d after death. A second study evaluated sensitivity and specificity using one, two, and five DEN-infected mosquitoes removed after 7,10, 14, 21, and 30 d application and tested by RT-PCR. All four DEN serotypes were individually inoculated in mosquitoes and evaluated using the same procedures as experiment 1. The four serotypes were detectable in as few as one mosquito 30 d after applications to the lure with no evidence of cross-reactivity. The combination of sticky lures and RT-PCR show promise for mosquito and dengue virus surveillance and warrant further evaluation.

Expansion of the antigenic repertoire of a single T cell receptor upon T cell activation

Activated T cells and their naive precursors display different functional avidities for peptide/MHC, but are thought to have identical antigenic repertoires. We show that, following activation with a cognate mimotope (NRP), diabetogenic CD8(+) T cells expressing a single TCR (8.3) respond vigorously to numerous peptide analogs of NRP that were unable to elicit any responses from naive 8.3-CD8(+) T cells, even at high concentrations. The NRP-reactive, in vivo activated CD8(+) cells arising in pancreatic islets of nonobese diabetic mice are similarly promiscuous for peptide/MHC, and paradoxically this promiscuity expands as the aviditiy of the T cell population for NRP/MHC increases with age. Thus, activation and avidity maturation of T lymphocyte populations can lead to dramatic expansions in the range of peptides that elicit functional T cell responses.