Bacteria have been found to play major roles in many physiologic/disease processes including cancer. The presence of bacteria within brain tumors has never been explored. The aim of this study was to examine the microbiome of Glioblastoma. A cohort of 40 glioblastoma samples (FFPE), from two medical centers served for DNA extraction using a specialized extraction protocol that includes a bead beating step to ensure complete bacterial DNA recovery. A set of negative controls was introduced at different steps of the assay to identify and monitor contaminating bacterial DNA. We measured the levels of bacterial DNA in the samples using a RT-qPCR assay, amplifying the bacterial 16S rRNA gene and detected bacterial DNA in over 40% of the samples. To characterize the bacterial taxa that are present in GBM tumors, we applied 16S DNA sequencing on the samples. After implementing a stringent set of filters on the sequencing data, eliminating contaminating signal, we detected a total of 22 bacterial taxa in GBM tumors. To visualize bacteria in GBM tissues and learn about their localization within the tissue we used immunohistochemistry staining with anti-lipopolysaccharide (LPS) and anti-lipoteichoic acid (LTA) antibodies detecting gram negative and gram positive bacteria (correspondingly). Bacteria were also visualized by staining bacterial RNA using a 16S rRNA in situ hybridization assay. Staining of a human GBM tissue microarray (TMA) containing 32 cases of GBM showed that the majority of cases stained positive for LPS and ~40% were positive for 16S rRNA staining. Bacterial LPS and 16S rRNA were localized mainly inside the tumor cells. Our study demonstrates, for the first time, that bacteria or bacterial components are present in human Glioblastoma tumors. We are currently expanding our study cohort in order to better define the bacteria found within glioblastoma samples and assess their possible effects

Auditory training (AT) has limited generalization to non-trained stimuli. Therefore, in the current study, we tested the effect of stimuli similar to that used in daily life: sentences in background noise. The sample consisted of 15 Hebrew-speaking adults aged 61–88 years with bilateral hearing impairment who engaged in computerized auditory training at home four times per week over a two-month period. Significant improvements were observed in sentences comprehension (Hebrew AzBio (HeBio) sentences test) with both four-talker-babble-noise (4TBN) and speech-shaped-noise (SSN) and in words comprehension (consonant-vowel-consonant (CVC) words test), following one month of AT. These improvements were sustained for two months after completing the AT. No evidence of spontaneous learning was observed in the month preceding training, nor was there an additional training effect in the additional month. Participants’ baseline speech perception abilities predicted their post-training speech perception improvements in the generalization tasks. The findings suggest that top-down generalization occurs from sentences to words and from babble noise to SSN and quiet conditions. Consequently, synthetic training tasks focusing on sentence-level comprehension accompanied by multi-talker babble noise should be prioritized. Moreover, an individualized approach to AT has demonstrated effectiveness and should be considered in both clinical and research settings.

Implementation of chaotic signals and of chaotic sequences in Code Division Multiple Access (CDMA) communication systems is considered. The performance of such CDMA direct sequence spread spectrum systems is analyzed based on the cross correlation between the chaotic signals (sequences). The cross correlation is found to be between the upper bounds obtained for m-sequences and for Gold sequences. Receiver architectures which exploits the self synchronization feature of chaotic systems are proposed, for a single user receiver and for a two users receiver. In a two users network, with negligible background noise, the performance of the self synchronized two users receiver is superior to the performance of the conventional single user receiver.

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