Cluster headache due to structural lesions: A systematic review of published cases

BACKGROUND Cluster headache(CH)is a severe incapacitating headache disorder.By definition,its diagnosis must exclude possible underlying structural conditions.AIM To review available information on CLH caused by structural lesions and to provide better guides in the distinguishing process and to ensure that there is not a potentially treatable structural lesion.METHODS We conducted a systematic review of 77 published cases of symptomatic CH and cluster-like headache(CLH)in PubMed and Google Scholar databases.RESULTS Structural pathologies associated with CH were vascular(37.7%),tumoral(32.5%)and inflammatory(27.2%).Brain mass-like lesions(tumoural and inflammatory)were the most common diseases(28.6%),among which 77.3%lesions were at the suprasellar(pituitary)region.Cases of secondary CH related to sinusitis rose dramatically,occupying 19.5%.The third most common disease was internal carotid artery dissection,accounting for 14.3%.Atypical clinical features raise an early suspicion of a secondary cause:Late age at onset and eye and retroorbital pains were common conditions requiring careful evaluation and were present in at least one-third of cases.Abnormal neurological examination was the most significant red flag for impaired cranial nerves.CLH patients may be responsive to typical CH treatments;therefore,the treatment response is not specific.CLH can be triggered by contralateral structural pathologies.CLH associated with sinusitis and cerebral venous thrombosis required more attention.CONCLUSION Since secondary headache could perfectly mimick primary CH,neuroimaging should be conducted in patients in whom primary and secondary headaches are suspected.Cerebral magnetic resonance imaging scans is the diagnostic management of choice,and further examinations include vessel imaging with contrast agents and dedicated scans focusing on specific cerebral areas(sinuses,ocular and sellar regions).Neuroimaging is as necessary at follow-up visits as at the first observation.

Protocol for the application of cooperative MIMO based on clustering in sparse wireless sensor networks

Wireless sensor networks （WSN） using cooperative multiple-input multiple-output （MIMO） communication are effective tools to collect data in several environments. However, how to apply cooperative MIMO in WSN remains a critical challenge, especially in sparse WSN. In this article, a novel clustering scheme is proposed for the application of cooperative MIMO in sparse WSN by extending the traditional low-energy adaptive clustering hierarchy （LEACH） protocol. This clustering scheme solves the problem that the cluster heads （CH） cannot find enough secondary cluster heads （SCH）, which are used to cooperate and inform multiple-antenna transmitters with CHs. On the basis of this protocol, the overall energy consumption of the networks model is developed, and the optimal number of CHs is obtained. The simulation results show that this protocol is feasible for the sparse WSN. The simulation results also illustrate that this protocol provides significant energy efficiencies, even after allowing for additional overheads.

Global regulation of fungal secondary metabolism in Trichoderma reesei by the transcription factor Ypr1,as revealed by transcriptome analysis

Trichoderma reesei Rut-C-30 is a well-known robust producer of cellulolytic enzymes,which are used to degrade lignocellulosic biomass for the sustainable production of biofuels and biochemicals.However,studies of its sec-ondary metabolism and regulation remain scarce.Ypr1 was previously described as a regulator of the biosynthesis of the yellow pigment sorbicillin(a bioactive agent with great pharmaceutical interest)in T.reesei and several other fungi.However,the manner in which this regulator affects global gene transcription has not been explored.In this study,we report the effect of Ypr1 on the regulation of both the secondary and primary metabolism of T.reesei Rut-C30.A global gene transcription profile was obtained using a comparative transcriptomic analysis of the wild-type strain T.reesei Rut-C-30 and its ypr1 deletion mutant.The results of this analysis suggest that,in addition to its role in regulating sorbicillin and the major extracellular(hemi)cellulases,Ypr1 also affects the transcription of genes encoding several other secondary metabolites.Although the primary metabolism of T.reeseiΔypr1 became less active compared with that of T.reesei Rut-C-30,several gene clusters involved in its secondary metabolism were activated,such as the gene clusters for the biosynthesis of specific polyketides and non-ribosomal peptides,together with the“sorbicillinoid-cellulase”super cluster,indicating that specific secondary metabolites and cellulases may be co-regulated in T.reesei Rut-C-30.The results presented in this study may benefit the development of genetic engineering strategies for the production of sorbicillin by T.reesei Rut-C-30,and provide insights for enhancing sorbicillin production in other filamentous fungal producers.