Transthyretin V122I amyloidosis with clinical and histological evidence of amyloid neuropathy and myopathy

Hereditary transthyretin amyloidosis (ATTR) is a genetically and clinically heterogeneous disease manifesting with predominant peripheral and autonomic neuropathy; cardiomyopathy, or both. ATTR V122I is the most common variant associated with non-neuropathic familial amyloid cardiomyopathy. We present an unusual case of V122I amyloidosis with features of amyloid neuropathy and myopathy, supported by histological confirmation in both sites and diffuse tracer uptake on (99m)Tc-3,3-Diphosphono-1,2-Propanodicarboxylic acid (DPD) scintigraphy throughout skeletal and cardiac muscle. A 64 year old Jamaican man presented with cardiac failure. Cardiac MR revealed infiltrative cardiomyopathy; abdominal fat aspirate confirmed the presence of amyloid, and he was homozygous for the V122I variant of transthyretin. He also described general weakness and EMG demonstrated myopathic features. Sural nerve and vastus lateralis biopsy showed TTR amyloid. The patient is being treated with diflunisal, an oral TTR stabilising agent. Symptomatic myopathy and neuropathy with confirmation of tissue amyloid deposition has not previously been described. Extracardiac amyloidosis has implications for diagnosis and treatment.

Oculoleptomeningeal Amyloidosis associated with transthyretin Leu12Pro in an African patient

Oculoleptomeningeal amyloidosis is a rare manifestation of hereditary transthyretin (TTR) amyloidosis. Here, we present the first case of leptomeningeal amyloidosis associated with the TTR variant Leu12Pro mutation in an African patient. A 43-year-old right-handed Nigerian man was referred to our centre with rapidly progressive neurological decline. He presented initially with weight loss, confusion, fatigue, and urinary and erectile dysfunction. He then suffered recurrent episodes of slurred speech with right-sided weakness. He went on to develop hearing difficulties and painless paraesthesia. Neurological examination revealed horizontal gaze-evoked nystagmus, brisk jaw jerk, increased tone, brisk reflexes throughout and bilateral heel-shin ataxia. Magnetic resonance imaging showed extensive leptomeningeal enhancement. Cerebrospinal fluid analysis showed a raised protein of 6.4 g/dl. Nerve conduction studies showed an axonal neuropathy. Echocardiography was characteristic of cardiac amyloid. TTR gene sequencing showed that he was heterozygous for the leucine 12 proline mutation. Meningeal and brain biopsy confirmed widespread amyloid angiopathy. TTR amyloidosis is a rare cause of leptomeningeal enhancement, but should be considered if there is evidence of peripheral or autonomic neuropathy with cardiac or ocular involvement. The relationship between different TTR mutations and clinical phenotype, disease course, and response to treatment remains unclear.

Having our yards and sharing them too: the collective effects of yards on native bird species in an urban landscape

Residential yards comprise a substantial portion of urban landscapes, and the collective effects of the management of many individual yards may “scale up” to affect urban biodiversity. We conducted bird surveys and social surveys in Chicago-area (Illinois, USA) residential neighborhoods to identify the relative importance of yard design and management activities for native birds. We found that groups of neighboring yards, in the aggregate, were more important for native bird species richness than environmental characteristics at the neighborhood or landscape scale. The ratio of evergreen to deciduous trees in yards and the percentage of yards with trees and plants with fruits or berries were positively associated with native bird species richness, whereas the number of outdoor cats had a negative association. The number of birdfeeders was not an important predictor for native species richness. We also found that migratory birds were observed on transects with more wildlife-friendly features in yards, and nonnative birds were observed on transects with greater numbers of outdoor cats and dogs. Our results highlight the potential importance of residential matrix management as a conservation strategy in urban areas.

Renal transplantation in systemic amyloidosis-importance of amyloid fibril type and precursor protein abundance

Renal transplantation remains contentious in patients with systemic amyloidosis due to the risk of graft loss from recurrent amyloid and progressive disease. Outcomes were sought among all patients attending the UK National Amyloidosis Centre who received a renal transplant (RTx) between January 1978 and May 2011. A total of 111 RTx were performed in 104 patients. Eighty-nine percent of patients with end-stage renal disease (ESRD) due to hereditary lysozyme and apolipoprotein A-I amyloidosis received a RTx. Outcomes following RTx were generally excellent in these diseases, reflecting their slow natural history; median graft survival was 13.1 years. Only 20% of patients with ESRD due to AA, AL and fibrinogen amyloidosis received a RTx. Median graft survival was 10.3, 5.8 and 7.3 years in these diseases respectively, and outcomes were influenced by fibril precursor protein supply. Patient survival in AL amyloidosis was 8.9 years among those who had achieved at least a partial clonal response compared to 5.2 years among those who had no response (p = 0.02). Post-RTx chemotherapy was administered successfully to four AL patients. RTx outcome is influenced by amyloid type. Suppression of the fibril precursor protein is desirable in the amyloidoses that have a rapid natural history.

Scale-dependent neighborhood effects: shared doom and associational refuge

A resource's susceptibility to predation may be influenced by its own palatability and the palatability of its neighbors. We tested for effects of plant chemical defenses on seed survival by manipulating the frequency of palatable and less palatable sunflower seeds in food patches subject to harvest by fox squirrels (Sciurus niger) and gray squirrels (Sciurus carolinensis). We varied resource distributions at three scales: among stations (aggregates of patches ca. 50 m apart), among patches immediately adjacent to each other, and within patches. When food patches were segregated into high-palatability and low-palatability stations (Experiment 1), seeds suffered greater mortality at stations with high levels of palatable seeds. In the same experiment, within patches, squirrels selected strongly for palatable seeds over less palatable seeds. When high- and low-palatability food patches were placed together at the same stations (Experiment 2), increasing densities of co-occurring palatable seeds amplified the mortality of less palatable seeds, indicating "shared doom." When palatable and less palatable seeds were partitioned into micropatches (Experiment 3), associational effects disappeared, as predicted. Furthermore, selectivity in less palatable patches increased as the initial densities of palatable seeds increased, and selectivity in palatable patches decreased as the initial densities of less palatable seeds increased. Foraging theory predicts associational effects among prey that vary in palatability. Our results show how the type and magnitude of associational effects emerge from the interplay among the spatial scale of prey heterogeneity, the diet selection strategy, and the scale-dependent foraging responses of the consumer.

Solid organ transplantation in AL amyloidosis

Vital organ failure remains common in AL amyloidosis. Solid organ transplantation is contentious because of the multisystem nature of this disease and risk of recurrence in the graft. We report outcome among all AL patients evaluated at the UK National Amyloidosis Centre who received solid organ transplants between 1984 and 2009. Renal, cardiac and liver transplants were performed in 22, 14 and 9 patients respectively, representing <2% of all AL patients assessed during the period. One and 5-year patient survival was 95% and 67% among kidney recipients, 86% and 45% among heart recipients and 33% and 22% among liver recipients. No renal graft failed due to recurrent amyloid during median (range) follow up of 4.8 (0.2-13.3) years. Median patient survival was 9.7 years among 8/14 cardiac transplant recipients who underwent subsequent stem cell transplantation (SCT) and 3.4 years in six patients who did not undergo SCT (p = 0.01). Amyloid was widespread in all liver transplant recipients. Solid organ transplantation has rarely been performed in AL amyloidosis, but these findings demonstrate feasibility and support a role in selected patients.

Investigation of nicotine binding to THP-1 cells: evidence for a non-cholinergic binding site

Nicotine is known to modulate immune function, but reports have produced conflicting evidence as to whether nicotinic acetylcholine (nACh) receptors are responsible for these effects. This study was designed to examine the identity of nicotine-binding sites on immune cells using a human leukaemic monocytic cell line, THP-1, that is known to have functions that are modulated by nicotine. Binding studies were performed on THP-1 whole cells using [3H]nicotine as a probe to analyse any possible nicotine-binding sites on these cells. Saturation analysis of THP-1 cells revealed the presence of 2 distinct binding sites; one with a K(d1) of 3.5 +/- 2.1 x 10(-9) M and a B(max1) of 4100 +/- 560 sites/cell (designated the high-affinity site) and the other with a K(d2) of 27 +/- 9.2 x 10(-9) M and a B(max2) of 11,600 +/- 630 sites/cell (low-affinity site). Competition analysis revealed that one site had an affinity to a range of cholinergic ligands including epibatidine and cytisine. When saturation analysis of [3H](-)-nicotine to THP-1 cells was performed in the presence of 1 x 10(-6) M epibatidine, only one binding site was detected. Comparisons of K(d) and B(max) values showed that the high-affinity site was not occluded by epibatidine. No drugs tested displayed any affinity for the high-affinity site except the two enantiomers of nicotine. The high-affinity site was shown to be stereoselective for the (+)-enantiomer of nicotine as shown by K(i) values produced by competition analysis in the presence of 1 x 10(-6) M epibatidine. These values were 5.7 +/- 0.32 x 10(-11) M and 1.9 +/- 4.9 x 10(-9) M for (+)-nicotine and (-)-nicotine, respectively. This study presents evidence for a possible non-cholinergic binding site that may play a role in the mechanism of immunomodulation by nicotine.

Reactive oxygen species generation and histamine release by activated mast cells: modulation by nitric oxide synthase inhibition

1. We have examined the generation of intracellular reactive oxygen species (ROS) and release of histamine by rat peritoneal mast cells (RPMC) in response to stimulation with antigen (ovalbumin), compound 48/80, nerve growth factor (NGF) and substance P (SP). 2. We have also examined the effects of the non-specific nitric oxide synthase inhibitor, L-NAME (100 microM) upon the release of histamine and generation of intracellular ROS in response to the named secretagogues. 3. Ovalbumin (100 - 1000 microg ml-1), compound 48/80 (0.1 - 100 microg ml-1), NGF (0.1 - 100 microg ml-1), and SP (5 - 50 microM), caused a concentration-dependent release of histamine from RPMC. 4. Ovalbumin (1 ng ml-1 - 0.1 microg ml-1), compound 48/80 (1 - 100 microg ml-1), NGF (1 pg ml-1 - 1 microg ml-1), and SP (0.005 - 50 microM) caused a concentration-dependent generation of intracellular ROS by RPMC. 5. Pre-incubation of RPMC with L-NAME (100 microM) caused a significant enhancement of both histamine release and intracellular ROS from RPMC in response to ovalbumin, compound 48/80, NGF and SP. 6. Our data demonstrate that NGF, SP and ovalbumin are capable of causing intracellular ROS generation by RPMC at lower concentrations than those causing significant histamine release and we speculate that this may contribute to the activation of cytokine production. 7. The data also show that NO modulates histamine release, and ROS generation in response to the secretagogues used. This may have significance in pathologies where NO synthesis is decreased, leading to an increased activation of mast cells.

A comparison of the inhibitory effects of budesonide, beclomethasone dipropionate, dexamethasone, hydrocortisone and tixocortol pivalate on cytokine release from leukocytes recovered from human bronchoalveolar lavage

OBJECTIVE

The potency of budesonide, beclomethasone dipropionate (BDP), dexamethasone, hydrocortisone and tixocortol pivalate as inhibitors of interleukin-5 (IL-5) and interferon-gamma (IFNgamma) release from human bronchoalveolar lavage cells in vitro were compared.

METHODS

BAL leukocytes were obtained from patients undergoing bronchoscopy for diagnostic purposes. BAL leukocytes were activated with PHA (10 microg/ml) and PMA (10 ng/ml) and cultured for 48 h in the presence or absence of glucocorticoids. Culture supernatants were assayed for cytokines by ELISA.

RESULTS

Budesonide (10(-9) to 10(-7) M) and BDP (10(-8) to 10(-6) M) were the most potent glucocorticoids tested. Dexamethasone (10(-7) to 10(-5) M) was less potent, and the maximum inhibitory effect of dexamethasone was less than that produced by than budesonide or BDP. Tixocortol pivalate (10(-6) to 3 x 10(-5) M) caused a concentration-related inhibition of IL-5 release but only the highest concentration tested inhibited the release of IFNgamma. Hydrocortisone (10(-4) M) inhibited IL-5 and IFNgamma release.

CONCLUSION

We conclude that, unlike the other glucocorticoids tested, tixocortol pivalate appeared to be a selective inhibitor of IL-5 release. Possible mechanisms for this selectivity are discussed.