Portal protein diversity and phage ecology

Oceanic phages are critical components of the global ecosystem, where they play a role in microbial mortality and evolution. Our understanding of phage diversity is greatly limited by the lack of useful genetic diversity measures. Previous studies, focusing on myophages that infect the marine cyanobacterium Synechococcus, have used the coliphage T4 portal-protein-encoding homologue, gene 20 (g20), as a diversity marker. These studies revealed 10 sequence clusters, 9 oceanic and 1 freshwater, where only 3 contained cultured representatives. We sequenced g20 from 38 marine myophages isolated using a diversity of Synechococcus and Prochlorococcus hosts to see if any would fall into the clusters that lacked cultured representatives. On the contrary, all fell into the three clusters that already contained sequences from cultured phages. Further, there was no obvious relationship between host of isolation, or host range, and g20 sequence similarity. We next expanded our analyses to all available g20 sequences (769 sequences), which include PCR amplicons from wild uncultured phages, non-PCR amplified sequences identified in the Global Ocean Survey (GOS) metagenomic database, as well as sequences from cultured phages, to evaluate the relationship between g20 sequence clusters and habitat features from which the phage sequences were isolated. Even in this meta-data set, very few sequences fell into the sequence clusters without cultured representatives, suggesting that the latter are very rare, or sequencing artefacts. In contrast, sequences most similar to the culture-containing clusters, the freshwater cluster and two novel clusters, were more highly represented, with one particular culture-containing cluster representing the dominant g20 genotype in the unamplified GOS sequence data. Finally, while some g20 sequences were non-randomly distributed with respect to habitat, there were always numerous exceptions to general patterns, indicating that phage portal proteins are not good predictors of a phage's host or the habitat in which a particular phage may thrive.

Expression of the Water Channel Protein Aquaporin-9 in Human Astrocytic Tumours: Correlation with Pathological Grade

This study investigated the expression of the water channel protein aquaporin-9 (AQP9) in 100 cases of human astrocytic tumour compared with normal brain tissue. AQP9 mRNA and protein were assessed using reverse transcription-polymerase chain reaction and Western blot, respectively. The expression of both AQP9 mRNA and protein in astrocytic tumours was significantly greater than in normal brain tissue and was positively correlated with pathological grade. No significant correlations were found between the level of AQP9 mRNA or protein expression and gender, age, tumour size or tumour site. This study indicates that AQP9 may play an important role in the malignant progression of brain astrocytic tumours and may, therefore, be useful as a biomarker in its diagnosis and as a new target for gene therapy. The molecular mechanisms by which AQP9 affects the proliferation and apoptosis of astrocytic tumours need to be studied further.

Maintenance treatment with budesonide 6 mg versus 9 mg once daily in patients with Crohn's disease in remission

BACKGROUND

In previous trials, budesonide 6 mg/day was able to prolong the time to relapse in patients with quiescent Crohn's disease and budesonide 9 mg/day was effective in active disease with limited side effects. The aim of this study was to compare the effectiveness of budesonide 9 mg vs 6 mg once daily on the maintenance of remission and occurrence of adverse events.

METHODS

Double-blind, randomised trial in patients with Crohn's disease in remission. Patients were randomised to receive 6 mg/day or 9 mg/day of budesonide (Budenofalk) without concomitant treatment for Crohn's disease. Endpoints were the time to relapse and relapse rates after one year.

RESULTS

Seventy-six patients were randomised to 6 mg/day and 81 patients to 9 mg/day. Survival analysis showed no differences in the time to relapse. One-year relapse rates were not significantly different (6 mg group 24%; 9 mg group 19%). Any adverse event was reported in 61 and 68% of patients in the 6 mg and 9 mg groups, respectively; none of the 12 serious adverse events were drug related.

CONCLUSION

The one-year relapse rates were low and not significantly different between the group of patients treated with budesonide 6 mg vs 9 mg/day. Also, time to relapse and the number of adverse events were similar in both treatment groups.

Regulation of adiponectin in adipocytes upon exposure to HIV-1

OBJECTIVES

Adipose dysregulation, dyslipidemia, and insulin resistance are hallmarks of HIV-related lipodystrophy. The precise mechanisms behind these disturbances are unknown. In HIV-infected patients, we previously demonstrated a strong relationship between lipodystrophy and levels of adiponectin, an adipose peptide implicated in regulation of glucose and lipid metabolisms. In this study we investigated the effect of HIV on adipocytes, to determine whether HIV can directly infect adipocytes and/or alter the regulation and secretion of the adipocyte-derived hormone adiponectin.

METHODS

Human subcutaneous preadipocytes and adipocytes were exposed to HIV-1 under various conditions. Adiponectin was measured in supernatants and cell lysates.

RESULTS

Although adipocytes expressed CD4, the major HIV receptor, they could not be infected in vitro. However, exposure to HIV dramatically increased the secretion of adiponectin from human adipocytes, in the absence of infection. This was exacerbated with sustained exposure to HIV in a transwell assay. Further, human peripheral mononuclear cells also produced adiponectin, but this was largely dependent upon T-cell activation.

CONCLUSIONS

We propose that the stimulation of adiponectin production by HIV can perturb adiponectin regulation, leading to substantially decreased levels upon viral suppression by antiretroviral therapy. These data suggest a potential molecular mechanism of adiponectin regulation in HIV-infected patients.

Expression of CD30 (Ber-H2) in nasopharyngeal carcinoma, undifferentiated type and lymphoepithelioma-like carcinoma. A comparison study with anaplastic large cell lymphoma

AIMS

Undifferentiated nasopharyngeal non-keratinizing carcinoma (UNPC), formerly known as lymphoepithelioma, frequently metastasizes at an early stage to regional lymph nodes and, thus, may be difficult to distinguish from Hodgkin's lymphoma (HL) or anaplastic large cell lymphoma (ALCL). CD30 expression is a useful diagnostic stain in both HL and ALCL, but its expression in UNPC deserves clarification. The aim of this study was to evaluate CD30 expression in UNPC and lymphoepithelioma-like carcinoma (LELC) from other anatomic locations and compare it with ALCL and squamous cell carcinoma (SCC).

METHODS AND RESULTS

CD30 immunoreactivity was examined in 38 cases of primary or metastatic UNPC, six cases of LELC, 10 cases of SCC and seven cases of ALCL. CD30 immunoreactivity was observed in four of 38 (10.5%) cases of UNPC. CD30 staining was absent in all cases of LELC (0/6) and SCC (0/10). All cases of ALCL (7/7) were strongly positive for CD30.

CONCLUSIONS

The majority of cases of UNPC are immunohistochemically negative for CD30; however, a small subset of cases expresses CD30 antigen. These findings provide additional evidence that CD30 expression is not restricted to neoplasms of lymphoid origin. This should be taken into consideration when interpreting CD30 immunohistology and the possibility of UNPC.

Biodiversity as a source of anticancer drugs

Natural Products have been the most significant source of drugs and drug leads in history. Their dominant role in cancer chemotherapeutics is clear with about 74% of anticancer compounds being either natural products, or natural product-derived. The biodiversity of the world provides a resource of unlimited structural diversity for bioprospecting by international drug discovery programs such as the ICBGs and NCDDGs, the latter focusing exclusively on anticancer compounds. However, many sources of natural products remain largely untapped. Technology is gradually overcoming the traditional difficulties encountered in natural products research by improving access to biodiverse resources, and ensuring the compatibility of samples with high throughput procedures. However, the acquisition of predictive biodiversity remains challenging. Plant and organism species may be selected on the basis of potentially useful phytochemical composition by consulting ethnopharmacological, chemosystematic, and ecological information. On the conservation/political front, the Convention on Biological Diversity (CBD) is allaying the anxiety surrounding the notion of biopiracy, which has defeated many attempts to discover and develop new natural products for human benefit. As it becomes increasingly evident and important, the CBD fosters cooperation and adaptation to new regulations and collaborative research agreements with source countries. Even as the past inadequacies of combinatorial chemistry are being analyzed, the intrinsic value of natural products as a source of drug leads is being increasingly appreciated. Their rich structural and stereochemical characteristics make them valuable as templates for exploring novel molecular diversity with the aim of synthesizing lead generation libraries with greater biological relevance. This will ensure an ample supply of starting materials for screening against the multitude of potentially "druggable" targets uncovered by genomics technologies. Far from being mutually exclusive, biodiversity and genomics should be the driving force of drug discovery in the 21st century.

Computed tomography angiography for the detection and characterization of intra-cranial aneurysms: Current status

Multidetector computed tomography angiography (MD-CTA) of the intra-cranial vessels is now a routine examination, and is becoming fully integrated into the imaging and treatment algorithm of patients presenting with acute subarachnoid haemorrhage in many centres in the UK and Europe. The development and current status of CTA for cerebral aneurysms, and the strengths and limitations of this technique are herein reviewed.

Computed tomography pseudofractures of the mid face and skull base

Thin-section multislice CT delineates numerous normal skull-base and mid-facial bony discontinuities. These represent sutures, fissures and neurovascular foramina or channels, and should be differentiated from fractures. This pictorial review describes and illustrates the characteristic location and multiplanar CT appearances of these structures. Their clinical significance in terms of pathological processes and surgical planning are discussed.

Caesarean scar pregnancy: a diagnosis to consider carefully in patients with risk factors

INTRODUCTION

Caesarean scar pregnancy is rare. A high index of suspicion is necessary to make the right diagnosis early.

CLINICAL PICTURE

Two women, each with a history of 1 previous caesarean delivery, were initially diagnosed with spontaneous abortion in progress when ultrasonography scan revealed the gestational sac to be in the lower uterine cavity. Subsequent ultrasound scans showed that the gestational sac was actually in the anterior uterine wall at the level of the uterine isthmus.

TREATMENT

Both women were managed successfully with intrasac methotrexate injection.

OUTCOME

We report 2 cases of caesarean scar pregnancies mistaken for spontaneous abortions by experienced ultrasonographers.

CONCLUSION

This highlights the difficulty in differentiating between these 2 diagnoses and the importance of having a high index of suspicion in women with risk factors.

The flight experiment ANITA--a high performance air analyser for manned space cabins

Analysing Interferometer for Ambient Air (ANITA) is a flight experiment as precursor for a permanent continuous trace gas monitoring system on the International Space Station (ISS). For over 10 years, under various ESA contracts the flight experiment was defined, designed, breadboarded and set up. For the safety of the crew, ANITA can detect and quantify quasi on-line and simultaneously 32 trace gases with ppm or sub-ppm detection limits. The self-standing measurement system is based on Fourier Transform Infrared Spectrometer (FTIR) technology. The system represents a versatile air monitor allowing for the first time the detection and monitoring of trace gas dynamics of a spacecraft atmosphere. It is envisaged to accommodate ANITA in a Destiny (US LAB) Express Rack on the ISS. The transportation to the ISS is planned with the first ATV 'Jules Verne'. The options are either the Space Shuttle or the Automated Transfer Vehicle.

Carpal tunnel syndrome due to gouty infiltration of the lumbrical muscles and flexor tendons

A case of gout first presenting as carpal tunnel syndrome due to intratendinous and lumbrical muscle involvement with tophi is reported. Surgical decompression with excision of tophi and diseased muscle produced symptomatic relief.

[Study on cytotoxicity to leukemia cell and enhancement of immunologic functions of jiexinkang]

Cytotoxicity to leukemia cell and enhancement of immunologic functions of jiexinkang (JXK, traditional Chinese medicine) were observed in 34 cases of leukemia in vitro. The results showed that the leukemia cytotoxicity in the group of vincristine combined with JXK was significantly higher than that in vincristine alone. It was also found among all the observed cases that 20 refractory or recurred patients resistant to vincristine showed an obvious intention of the anti-toxicity efficiency when JXK was added. Jiexinkang alone had anti-leukemia cell effect, too. We explored JXK effects on immunologic functions in mice, and found that IFNr and NK activities of normal and experimental model mice were significantly higher than those of control group(P < 0.01). The results indicate that JXK has an effect of anti-leukemia cell and may improve the cell-immunologic functions.

A New Technique for the Measurement of the Dynamic Evolution of Surface Tension

We develop a novel technique which deduces the surface tension in air of a fluid as a function of surface age, beginning at age zero. The technique utilizes pointwise measurements of perpendicular free surface profiles of a steady oscillating jet corresponding to a discretization interval on the order of 0.1 ms. We implement the technique on constant-surface-tension test fluids (100% ethanol and 15% ethanol/85% water by volume) to demonstrate the extent to which the technique can qualitatively capture that the surface tensions of these fluids are constant in time, and quantitatively produce values of these constants consistent with static measurements. We then implement the technique on jets of two agricultural surfactant mixtures, Triton X-405 and Triton X-100, and quantitatively deduce the decay of surface tension as a function of surfactant concentration.

Frataxin expression rescues mitochondrial dysfunctions in FRDA cells

Friedreich's ataxia (FRDA) is the result of mutations in the nuclear-encoded frataxin gene, which is expressed in mitochondria. Several lines of evidence have suggested that frataxin is involved in mitochondrial iron homeostasis. We have transfected the frataxin gene into lymphoblasts of FRDA compound heterozygotes (FRDA-CH) with deficient frataxin expression to produce FRDA-CH-t cells in which message and protein are rescued to near-physiological levels. FRDA-CH cells were more sensitive to oxidative stress by challenge with free iron, hydrogen peroxide and the combination, consistent with a Fenton chemical mechanism of pathophysiology, and this sensitivity was rescued to control levels in FRDA-CH-t cells. Iron challenge caused increased mitochondrial iron levels in FRDA-CH cells, and a decreased mitochondrial membrane potential (MMP), both of which were rescued in FRDA-CH-t cells. The rescue of the low MMP, and high mitochondrial iron concentration by frataxin overexpression suggests that these cellular phenotypes are relevant to the central pathophysiological process in FRDA which is aggravated by exposure to free iron. However, even at physiological iron concentrations, FRDA-CH cells had decreased MMP as well as lower activities of aconitase and ICDH (two enzymes supporting MMP), and twice the level of filtrable mitochondrial iron (but no increase in total mitochondrial iron), and the observed phenotypes were either fully or partially rescued in FRDA-CH-t cells. Free iron is known to be toxic. The observation that frataxin deficiency (either directly or indirectly) causes an increase in filtrable mitochondrial iron provides a new hypothesis for the mechanism of cell death in this disease, and could be a target for therapy.

[Determination of chloramphenicol in chloramphenicol and dexamethasone sodium phosphate ear drops by first derivative spectrometry]

Determination of chloramphenicol in the ear drops by first derivative spectrometry was studied. The detecting wavelength was 303.0 nm. The linear range was 0-65.2 micrograms.ml-1 (r = 0.9999). The average recovery was 99.84%, RSD = 0.37% (n = 8). The method is simple and accurate.

Coping with chronic pain: a comparison of two measures

Cognitive-behavioral models of chronic pain hypothesize that how a person copes with pain influences how well he or she adjusts to the pain. Several measures have been developed to assess pain coping, but no studies have yet examined whether these measures are complementary or redundant. In the current study, two pain coping measures (the Chronic Pain Coping Inventory, CPCI, and the Coping Strategies Questionnaire, CSQ) were completed by a large number (N=564) of primarily male veterans referred to a chronic pain program. Regression analyses indicated that the CPCI scales did not contribute unique variance to the prediction of depression over and above the CSQ scales. The CSQ Catastrophizing scale was the single most powerful predictor of depression, although several other CSQ scales (Coping Self-Statements, Diverting Attention, and Increasing Behavioral Activities) also contributed. Both the CPCI and the CSQ contributed unique variance to the prediction of disability, although the CPCI scales appear to be more strongly related to disability than the CSQ scales. The CPCI Guarding scale was the single most powerful predictor of disability of all the coping responses assessed in this study. Other scales predicting disability were the CPCI Seeking Social Support, the CSQ Catastrophizing, and the CSQ Increasing Behavioral Activities. While both CSQ and CPCI contribute unique but modest variance to the prediction of pain severity, the CSQ Catastrophizing scale was the single most powerful predictor of pain severity. The findings of this study are consistent with cognitive-behavioral models of pain. Future research will need to determine whether changes in coping responses (catastrophizing and guarding, in particular) merely reflect, or actually influence, adjustment to chronic pain. In the meantime, clinicians would be wise to give these coping responses particular attention in chronic pain programs.