(−)-Epigallocatechin-3-gallate (EGCG) attenuates peripheral nerve degeneration in rat sciatic nerve crush injury

Recently, we have shown that green tea (GT) consumption improves both reflexes and sensation in unilateral chronic constriction injury to the sciatic nerve. Considering the substantial neuroprotective properties of GT polyphenols, we sought to investigate whether (−)-epigallocatechin-3-gallate (EGCG) could protect the sciatic nerve and improve functional impairments induced by a crushing injury. We also examined whether neuronal cell apoptosis induced by the crushing injury is affected by EGCG treatment.     

Molecular characterization of Rhizoctonia solani isolates the incitant of soybean root rot

Rhizoctonia solani isolates used in this investigation were identified as anastomosis-4 (AG-40), collected from different localities from Assiut governorate in Egypt. Pathogenicity test of seven isolates of R. solani was evaluated on soybean Giza 111 cultivar under greenhouse conditions. All tested isolates were able to infect soybean plants causing root rot with different degrees of severities, isolate No. 1, 2 and 3 showed significantly highest root rot severity, while isolate No. 5 gave the lowest percentage of root rot rating. The sodium dodecyl sulphate polyacrylamide gel electrophoresis patterns were used to compare three isolates of R. solani. There are no variations among R. solani isolates except a few exceptions according to their protein patterns. DNA markers obtained from all isolates showed genetic similarity among different isolates obtained from different geographical regions barring few exceptions. Correlation between DNA patterns of R. solani isolates and their virulence was detected, but no correlation with anastomosis groups (AG).     

Azo dying of α-keratin material improves microbial keratinase screening and standardization

Microbial conversion through enzymatic reactions has received a lot of attention as a cost-effective and environmentally friendly way to recover amino acids and short peptides from keratin materials. However, accurate assessment of microbial keratinase activity is not straightforward, and current available methods lack sensitivity and standardization. Here, we suggest an optimized Azokeratin assay, with substrate generated directly from azo-dyed raw keratin material. We introduced supernatant filtration in the protocol for optimal stopping of keratinase reactions instead of the widely used trichloroacetic acid (TCA), as it generated biases and impacted the sensitivity. We furthermore suggest a method for standardization of keratinase activity signals using proteinase K, a well-known keratinase, as a reference enabling reproducibility between studies. Lastly, we evaluated our developed method with several bacterial isolates through benchmarking against a commercial assay (Keratin Azure). Under different setups, the Azokeratin method was more sensitive than commonly used Keratin Azure-based assays (3-fold). We argue that this method could be applied with any type of keratin substrate, enabling more robust and sensitive results which can be used for further comparison with other studies, thus representing an important progress within the field of microbial keratin degradation.     

Oxidative Stress Alters Physiological and Morphological Neuronal Properties

We investigated the effects of H₂O₂-induced oxidative stress on the delayed-rectifier current (IK_DR), neuronal physiological and morphological properties. Measurements were obtained from hippocampal CA1 neurons in control solution and from the same neurons after exposure to oxidative stress (short- and long-term H₂O₂ external applications at 0.1, 1, and 10 mM). With short-term (6 min) H₂O₂ (1 mM) treatment, IK_DR measured in the H₂O₂-containing solution (778 ± 23 pA, n = 20), was smaller than that measured in the control Ca²⁺-free Hepes solution (1,112 ± 38 pA, n = 20). Coenzyme Q₁₀ (0.1 mM) pretreatment prevented the H₂O₂-induced inhibition of IK_DR. With long-term (40, 80 min) H₂O₂ (0.1, 10 mM) treatment, the neuron lost its distinctive shape (rounded up) and the neurite almost disappeared. These results suggest that oxidative stress, which inhibits IK_DR, can alter neural activity. The morphological changes caused by H₂O₂ support the idea that oxidative stress causes intracellular damage and compromises neural function.     

In vitro activity of some natural honeys against Entamoeba histolytica and Giardia lamblia trophozoites

Considering the potentiality of honey in combating diseases, the present study was carried out aiming to assess the in vitro antiprotozoal activity of several honeys (Ziziphus spina-christi, Acacia nilotica, Acacia seyal, and Cucurbita maxima) against Entamoeba histolytica and Giardia lamblia by employing the sub-culture method. All the tested honeys inhibited the growth of trophozoites, and the level of inhibition varied according to the assayed concentrations and incubation times. Acacia seyal honey had completely stopped motility of E. histolytica trophozoites at a concentration ≤ 50 µg/ml after incubation for 72 h. Ziziphus spina-christi, Acacia seyal, and Acacia nilotica honeys had completely inhibited the growth of Giardia lamblia trophozoites at concentration ≤ 200 µg/ml after 72 h. These inhibitory activities were similar to that of Metronidazole? which showed IC₅₀ = 0.27. The mammalian cytotoxicity of these honeys against normal Vero cell line which determined by applying MTT method verified the nontoxicity of the examined honeys. Also the proximate composition of the samples indicated compliance with the natural honey standards. The findings of the study indicate the need for in vivo studies and further investigations to identify active principles with antiprotozoal activities from natural honeys.     

Patterns of co-existence between humans and mammals in Yemen: some species thrive while others are nearly extinct

This paper describes the results of a camera-trapping study in Hawf, eastern Yemen, of the relationships between human presence and the richness, diversity and distribution of wild medium-sized and large mammals. The study comprised 3,351 trap-nights over 225.3 km² during which 963 captures of 14 mammalian species and 985 captures of humans were obtained. Human presence was positively linked with species richness and diversity, but only when the number of human captures was ≤100 captures/site. At higher numbers of human captures, the positive trend reversed and only three species (wolf, fox and porcupine) succeeded in dominating their communities. Human presence was also strongly and positively associated with colonization and occupancy of some species, but decreased their detection probabilities. Contrary to expectations, human presence did not affect activity patterns of species. Co-existence between human presence and mammals caused by resource sharing, viz. establishment and use of same trails and water sources, attraction to livestock, garbage and food leftovers, is discussed. In contrast, the leopard, wild cat, Nubian ibex and mountain gazelle are severely depleted. Co-existence between humans and mammals has significant implications for proper management and wildlife conservation in unprotected human-dominated landscapes, protected areas and buffer zones of developing countries such as Yemen.     

Genomic profiling of solid tumors harboring BRD4-NUT and response to immune checkpoint inhibitors

BackgroundThe translocation t(15:19) produces the oncogenic BRD4-NUT fusion which is pathognomonic for NUT carcinoma (NC), which is a rare, but extremely aggressive solid tumor. Comprehensive genomic profiling (CGP) by hybrid-capture based next generation sequencing of 186+ genes of a cohort of advanced cancer cases with a variety of initial diagnoses harboring BRD4-NUT may shed further insight into the biology of these tumors and possible options for targeted treatment.Case presentationThirty-one solid tumor cases harboring a BRD4-NUT translocation are described, with only 16% initially diagnosed as NC and the remainder carrying other diagnoses, most commonly NSCLC—NOS (22%) and lung squamous cell carcinoma (NSCLC-SCC) (16%). The cohort was all microsatellite stable and harbored a low Tumor Mutational Burden (TMB, mean 1.7 mut/mb, range 0–4). In two index cases, patients treated with immune checkpoint inhibitors (ICPI) had unexpected partial or better responses of varying duration. Notably, four cases – including the two index cases - were negative for PD-L1 expression. Neo-antigen prediction for BRD4-NUT and then affinity modeling of the peptide-MHC (pMHC) complex for an assessable index case predicted very high affinity binding, both on a ranked (99.9%) and absolute (33 nM) basis.ConclusionsCGP identifies BRD4-NUT fusions in advanced solid tumors which carry a broad range of initial diagnoses and which should be re-diagnosed as NC per guidelines. A hypothesized mechanism underlying responses to ICPI in the low TMB, PD-L1 negative index cases is the predicted high affinity of the BRD4-NUT fusion peptide to MHC complexes. Further study of pMHC affinity and response to immune checkpoint inhibitors in patients with NC harboring BRD4-NUT is needed to validate this therapeutic hypothesis.     

The nitrone spin trap PBN alters the cellular response to H(2)O(2): activation of the EGF receptor/ERK pathway

The nitrone spin trap PBN has been shown to protect neuronal cells from reactive oxygen species both in culture and in vivo. As an approach to understanding the molecular mechanisms by which PBN may function to protect cells, we examined whether PBN alters the cellular response to reactive oxygen species. H(2)O(2) stimulation of PC-12 cells results in weak activation of both the ERK and JNK signal transduction pathways. PBN pretreatment of PC-12 cells, followed by H(2)O(2) stimulation, results in strong and selective activation of the pro-survival ERK pathway. H(2)O(2) induction of ERK activity in PBN-pretreated cells was shown to be dependent on extracellular Ca(+2) influx. Further analysis of the ERK pathway showed that in PBN-pretreated cells, EGF receptor and the adapter protein SHC were phosphorylated in a Ca(+2)-dependent, ligand-independent manner following H(2)O(2) stimulation. Interestingly, H(2)O(2) stimulation of PBN-pretreated cells results in only 30% of the increase in intracellular Ca(+2) as compared to untreated cells following H(2)O(2) stimulation. These data suggest a model in which PBN attenuates H(2)O(2)-induced Ca(+2) entry, yet magnifies or alters Ca(+2) action, resulting in the activation of the EGF receptor/ERK pathway.