Hypersensitivity pneumonitis secondary to lovebirds: a new cause of bird fancier's disease.

Hypersensitivity pneumonitis (HP) is an immunologically mediated lung disease due to the repetitive inhalation of antigens. Most new cases arise from residential exposures, notably to birds, and are thus more difficult to recognise. The present authors report a 59-yr-old male who complained of dyspnoea and cough while being treated with amiodarone. Pulmonary function tests revealed restriction and obstruction with low diffusing lung capacity for carbon monoxide and partial pressure of oxygen. A high-resolution computed tomography chest scan and bronchoalveolar lavage showed diffuse bilateral ground-glass attenuation and lymphocytic alveolitis, respectively. Initial diagnosis was amiodarone pulmonary toxicity, but because of a rapidly favourable evolution, this diagnosis was questioned. A careful environmental history revealed a close contact with lovebirds shortly before the onset of symptoms. Precipitins were strongly positive against lovebird droppings, but were negative against other avian antigens. The patient was diagnosed with hypersensitivity pneumonitis to lovebirds. Avoidance of lovebirds and steroid treatment led to rapid improvement. The present observation identifies a new causative agent for hypersensitivity pneumonitis and highlights the importance of a thorough environmental history and of searching for precipitins against antigens directly extracted from the patient's environment. These two procedures should allow a more precise classification of some cases of pneumonitis, and thus might avoid progression of active undiagnosed hypersensitivity pneumonitis to irreversible fibrosis or emphysema.

Malignant glioma after ependymoma: an unusual secondary malignancy

Purpose : Secondary malignancies (SM) are a known long-­‐term problem in children surviving brain tumors. We report on two unusual cases of SM observed after treatment of ependymoma. Case reports : 1. The first case is a female survivor of a low-­‐grade ependymoma (Grade II). She had been treated at the age of 3 months with surgery and chemotherapy. A relapse of the primary tumor happened two years later, which was completely removed and treated with local radiotherapy to the posterior fossa. Fifteen years after the first cancer, she developed a pontine glioma near the location of the previous radiotherapy. 2. The second case is a femal survivor of an ependymoma (Grade III) which was removed and irradiated when she was 4 years old. The child developed a pontine glioma near the location of the previous radiotherapy ten years after the diagnosis of the first cancer. Further extension of the disease showed after biopsy PNET-­‐ like features. Both patients passed away. Discussion and Conclusion : Second malignant neoplasia is a rare phenomenon and this risk should not overshadow the great success in treating cancer of childhood. Among the studied risk factors, young age and radiotherapy are well established. The reported patients were followed annually to ensure their remission and both developed symptoms and an unusual unreported secondary cancer a few months after the annual monitoring that was considered as normal. This issue highlights the complexity of monitoring cancer survivors and raises the question of the best way for their long-­‐term follow-­‐up.

Catabolite repression control of pyocyanin biosynthesis at an intersection of primary and secondary metabolism in Pseudomonas aeruginosa.

In Pseudomonas aeruginosa, the catabolite repression control (Crc) protein repressed the formation of the blue pigment pyocyanin in response to a preferred carbon source (succinate) by interacting with phzM mRNA, which encodes a key enzyme in pyocyanin biosynthesis. Crc bound to an extended imperfect recognition sequence that was interrupted by the AUG translation initiation codon.

Cryptic diversity among Western Palearctic tree frogs: postglacial range expansion, range limits, and secondary contacts of three European tree frog lineages (Hyla arborea group).

We characterize divergence times, intraspecific diversity and distributions for recently recognized lineages within the Hyla arborea species group, based on mitochondrial and nuclear sequences from 160 localities spanning its whole distribution. Lineages of H. arborea, H. orientalis, H. molleri have at least Pliocene age, supporting species level divergence. The genetically uniform Iberian H. molleri, although largely isolated by the Pyrenees, is parapatric to H. arborea, with evidence for successful hybridization in a small Aquitanian corridor (southwestern France), where the distribution also overlaps with H. meridionalis. The genetically uniform H. arborea, spread from Crete to Brittany, exhibits molecular signatures of a postglacial range expansion. It meets different mtDNA clades of H. orientalis in NE-Greece, along the Carpathians, and in Poland along the Vistula River (there including hybridization). The East-European H. orientalis is strongly structured genetically. Five geographic mitochondrial clades are recognized, with a molecular signature of postglacial range expansions for the clade that reached the most northern latitudes. Hybridization with H. savignyi is suggested in southwestern Turkey. Thus, cryptic diversity in these Pliocene Hyla lineages covers three extremes: a genetically poor, quasi-Iberian endemic (H. molleri), a more uniform species distributed from the Balkans to Western Europe (H. arborea), and a well-structured Asia Minor-Eastern European species (H. orientalis).

Do plants adjust their sex allocation and secondary sexual morphology in response to their neighbours?

BACKGROUND AND AIMS: Changes in the sex allocation (i.e. in pollen versus seed production) of hermaphroditic plants often occur in response to the environment. In some homosporous ferns, gametophytes choose their gender in response to chemical cues sent by neighbours, such that spores develop as male gametophytes if they perceive a female or hermaphrodite nearby. Here it is considered whether a similar process might occur in the androdioecious angiosperm species Mercurialis annua, in which males co-occur with hermaphrodites; previous work on a Spanish population of M. annua found that individuals were more likely to develop as males at high density. METHODS: Using a novel approach to treat plants with leachate from pots containing males or hermaphrodites of M. annua, the hypothesis that individuals assess their mating opportunities, and adjust their sex expression accordingly, was tested through an exchange of chemical cues through the soil. KEY RESULTS: For the population under study, from Morocco, no evidence was found for soil-signal-dependent sex expression: neither sex ratios nor sex allocation differed among experimental treatments. CONCLUSIONS: The results imply either that the Moroccan population under study behaves differently from that previously studied in Spain (pointing to potential geographical variation in plasticity for sex expression), or that our method failed to capture the signals used by M. annua for adjustment of sex expression.

The interface between oral and systemic health: the need for more collaboration.

The focus of this review is to highlight the need for improved communication between medical and dental professionals in order to deliver more effective care to patients. The need for communication is increasingly required to capitalise on recent advances in the biological sciences and in medicine for the management of patients with chronic diseases. Improvements in longevity have resulted in populations with increasing special oral-care needs, including those who have cancer of the head and neck, those who are immunocompromised due to HIV/AIDS, advanced age, residence in long-term care facilities or the presence of life-long conditions, and those who are receiving long-term prescription medications for chronic conditions (e.g., anti-hypertensives, anticoagulants, immunosuppressants, antidepressants). These medications can cause adverse reactions in the oral cavity, such as xerostomia and ulceration. Patients with xerostomia are at increased risk of tooth decay, periodontal disease and infection. The ideal management of such individuals should involve the collaborative efforts of physicians, nurses, dentists and dental hygienists, thus optimising treatment and minimising secondary complications deriving from the oral cavity.

Ischemic cecal perforation secondary to ESWL of junctional stone in ureterosigmoidostomy (Mainz Pouch II).

We report an unusual case of ischemic cecal perforation after extracorporeal shock wave lithotripsy for an impacted stone at the distal end of the right ureter of a ureterosigmoidostomy in a 78-year-old female patient.

Extra-articular knee resection for a secondary chondrosarcoma evolving from an isolated enchondroma of the distal femur: A case report.

Introduction: Enchondromas are among the most current benign bone tumours. Malignant degeneration is extremely rare (<1%) and generally presents as a low grade chondrosarcoma. For localized grade 1 lesions, the treatment of choice is curettage. Wide excision and reconstruction is generally not necessary, unless locally advanced or more aggressive behaviour is suspected at presentation. Case report: A healthy 72 yo male presented with pain and recurrent knee joint effusion. X-rays show a classical central distal metaphyseal enchondroma of the femur associated with subtle osteolysis of the lateral condyle. MRI confirms the presence of a locally aggressive chondromatous lesion based in a classical enchondroma. Core needle biopsy revealed a grade 1 chondrosarcoma, which was in contrast to the radiological aggressiveness of the lesion. Total body CT-scan did not reveal metastatic disease. A wide resection was planned, as a high-grade lesion and joint contamination was suspected. We performed an extra-articular knee resection and reconstruction with a hinged modular total knee megaprosthesis. The definitive histology was grade 1 chondrosarcoma, the surgical margins were wide. The evolution was favourable and the patient was able to perform all his activities of daily living independently without pain at 6 weeks postop. Knee flexion reached 90°. The oncologic screening at 18 months did not show local or distant recurrence. Conclusion: Joints near a benign tumour that suddenly become symptomatic or present an effusion might indicate a malignant transformation. Wide resection and prosthetic reconstruction remains an effective treatment option even in low grade cartilaginous lesions if (1) the adjacent joint is contaminated, or (2) joint-sparing surgery would result in a severe functional impairment of the limb.

Inferring the degree of incipient speciation in secondary contact zones of closely related lineages of Palearctic green toads (Bufo viridis subgroup).

Reproductive isolation between lineages is expected to accumulate with divergence time, but the time taken to speciate may strongly vary between different groups of organisms. In anuran amphibians, laboratory crosses can still produce viable hybrid offspring >20 My after separation, but the speed of speciation in closely related anuran lineages under natural conditions is poorly studied. Palearctic green toads (Bufo viridis subgroup) offer an excellent system to address this question, comprising several lineages that arose at different times and form secondary contact zones. Using mitochondrial and nuclear markers, we previously demonstrated that in Sicily, B. siculus and B. balearicus developed advanced reproductive isolation after Plio-Pleistocene divergence (2.6 My, 3.3-1.9), with limited historic mtDNA introgression, scarce nuclear admixture, but low, if any, current gene flow. Here, we study genetic interactions between younger lineages of early Pleistocene divergence (1.9 My, 2.5-1.3) in northeastern Italy (B. balearicus, B. viridis). We find significantly more, asymmetric nuclear and wider, differential mtDNA introgression. The population structure seems to be molded by geographic distance and barriers (rivers), much more than by intrinsic genomic incompatibilities. These differences of hybridization between zones may be partly explained by differences in the duration of previous isolation. Scattered research on other anurans suggests that wide hybrid zones with strong introgression may develop when secondary contacts occur <2 My after divergence, whereas narrower zones with restricted gene flow form when divergence exceeds 3 My. Our study strengthens support for this rule of thumb by comparing lineages with different divergence times within the same radiation.

Ammonium alters creatine transport and synthesis in a 3D culture of developing brain cells, resulting in secondary cerebral creatine deficiency.

Hyperammonemic disorders in pediatric patients lead to poorly understood irreversible effects on the developing brain that may be life-threatening. We showed previously that some of these NH4+-induced irreversible effects might be due to impairment of axonal growth that can be protected under ammonium exposure by creatine co-treatment. The aim of the present work was thus to analyse how the genes of arginine:glycine amidinotransferase (AGAT) and guanidinoacetate methyltransferase (GAMT), allowing creatine synthesis, as well as of the creatine transporter SLC6A8, allowing creatine uptake into cells, are regulated in rat brain cells under NH4+ exposure. Reaggregated brain cell three-dimensional cultures exposed to NH4Cl were used as an experimental model of hyperammonemia in the developing central nervous system (CNS). We show here that NH4+ exposure differentially alters AGAT, GAMT and SLC6A8 regulation, in terms of both gene expression and protein activity, in a cell type-specific manner. In particular, we demonstrate that NH4+ exposure decreases both creatine and its synthesis intermediate, guanidinoacetate, in brain cells, probably through the inhibition of AGAT enzymatic activity. Our work also suggests that oligodendrocytes are major actors in the brain in terms of creatine synthesis, trafficking and uptake, which might be affected by hyperammonemia. Finally, we show that NH4+ exposure induces SLC6A8 in astrocytes. This suggests that hyperammonemia increases blood-brain barrier permeability for creatine. This is normally limited due to the absence of SLC6A8 from the astrocyte feet lining microcapillary endothelial cells, and thus creatine supplementation may protect the developing CNS of hyperammonemic patients.

Analysis of secondary growth in the Arabidopsis shoot reveals a positive role of jasmonate signalling in cambium formation.

After primary growth, most dicotyledonous plants undergo secondary growth. Secondary growth involves an increase in the diameter of shoots and roots through formation of secondary vascular tissue. A hallmark of secondary growth initiation in shoots of dicotyledonous plants is the initiation of meristematic activity between primary vascular bundles, i.e. in the interfascicular regions. This results in establishment of a cylindrical meristem, namely the vascular cambium. Surprisingly, despite its major implications for plant growth and the accumulation of biomass, the molecular regulation of secondary growth is only poorly understood. Here, we combine histological, molecular and genetic approaches to characterize interfascicular cambium initiation in the Arabidopsis thaliana inflorescence shoot. Using genome-wide transcriptional profiling, we show that stress-related and touch-inducible genes are up-regulated in stem regions where secondary growth takes place. Furthermore, we show that the products of COI1, MYC2, JAZ7 and the touch-inducible gene JAZ10, which are components of the JA signalling pathway, are cambium regulators. The positive effect of JA application on cambium activity confirmed a stimulatory role of JA in secondary growth, and suggests that JA signalling triggers cell divisions in this particular context.

Leptin and smoking cessation: secondary analyses of a randomized controlled trial assessing physical activity as an aid for smoking cessation.

BACKGROUND: Smokers have a lower body weight compared to non-smokers. Smoking cessation is associated with weight gain in most cases. A hormonal mechanism of action might be implicated in weight variations related to smoking, and leptin might be implicated. We made secondary analyses of an RCT, with a hypothesis-free exploratory approach to study the dynamic of leptin following smoking cessation. METHODS: We measured serum leptin levels among 271 sedentary smokers willing to quit who participated in a randomized controlled trial assessing a 9-week moderate-intensity physical activity intervention as an aid for smoking cessation. We adjusted leptin for body fat levels. We performed linear regressions to test for an association between leptin levels and the study group over time. RESULTS: One year after smoking cessation, the mean serum leptin change was +3.23 mg/l (SD 4.89) in the control group and +1.25 mg/l (SD 4.86) in the intervention group (p of the difference < 0.05). When adjusted for body fat levels, leptin was higher in the control group than in the intervention group (p of the difference < 0.01). The mean weight gain was +2.91 (SD 6.66) Kg in the intervention and +3.33 (SD 4.47) Kg in the control groups, respectively (p not significant). CONCLUSIONS: Serum leptin levels significantly increased after smoking cessation, in spite of substantial weight gain. The leptin dynamic might be different in chronic tobacco users who quit smoking, and physical activity might impact the dynamic of leptin in such a situation. CLINICAL TRIAL REGISTRATION NUMBER: NCT00521391.