Helicobacter pylori apo-Fur Regulation Appears Unconserved Across Species

Shana Miles,Beth M. Carpenter,Hanan Gancz,D. Scott Merrell 한국미생물학회 2010 The journal of microbiology Vol.48 No.3

The Ferric Uptake Regulator (Fur) is a transcriptional regulator that is conserved across a broad number of bacterial species and has been shown to regulate expression of iron uptake and storage genes. Additionally, Fur has been shown to be an important colonization factor of the gastric pathogen Helicobacter pylori. In H. pylori, Fur-dependent regulation appears to be unique in that Fur is able to act as a transcriptional repressor when bound to iron as well as in its iron free (apo) form. To date, apo-regulation has not been identified in any other bacterium. To determine whether Fur from other species has the capacity for aporegulation, we investigated the ability of Fur from Escherichia coli, Campylobacter jejuni, Desulfovibrio vulgaris Hildenborough, Pseudomonas aeruginosa, and Vibrio cholerae to complement both iron-bound and apo-Fur regulation within the context of a H. pylori fur mutant. We found that while some Fur species (E. coli, C. jejuni, and V. cholerae) complemented iron-bound regulation, apo-regulation was unable to be complemented by any of the examined species. These data suggest that despite the conservation among bacterial Fur proteins, H. pylori Fur contains unique structure/function features that make it novel in comparison to Fur from other species.

Transcultural, Resistant, Everyday: New Photographic Histories of China and Japan

Shana J. Brown 고려대학교 민족문화연구원 2018 Cross-Currents Vol.0 No.26

These three books shed light on how much there is to celebrate in the trajectory from the Western-dominated photography of the mid-nineteenth century to the much more diffuse, diverse, and democratized photography of the twentieth. Not all photographers, or photographs, are benign. Just because an image is more similar to a selfie than an ethnographic type does not eliminate the potential for abuse. But few technologies have tied the world together so closely in our ability to imagine ourselves in affirming ways, as well as to preserve and complement others. Despite very dark chapters in the technology’s past, sometimes we take pictures because we like what we see...

Genomic versatility and functional variation between two dominant heterotrophic symbionts of deep-sea Osedax worms.

Goffredi, Shana K,Yi, Hana,Zhang, Qingpeng,Klann, Jane E,Struve, Isabelle A,Vrijenhoek, Robert C,Brown, C Titus Nature Publishing Group 2014 The ISME journal Vol.8 No.4

<P>An unusual symbiosis, first observed at ~3000 m depth in the Monterey Submarine Canyon, involves gutless marine polychaetes of the genus Osedax and intracellular endosymbionts belonging to the order Oceanospirillales. Ecologically, these worms and their microbial symbionts have a substantial role in the cycling of carbon from deep-sea whale fall carcasses. Microheterogeneity exists among the Osedax symbionts examined so far, and in the present study the genomes of the two dominant symbionts, Rs1 and Rs2, were sequenced. The genomes revealed heterotrophic versatility in carbon, phosphate and iron uptake, strategies for intracellular survival, evidence for an independent existence, and numerous potential virulence capabilities. The presence of specific permeases and peptidases (of glycine, proline and hydroxyproline), and numerous peptide transporters, suggests the use of degraded proteins, likely originating from collagenous bone matter, by the Osedax symbionts. (13)C tracer experiments confirmed the assimilation of glycine/proline, as well as monosaccharides, by Osedax. The Rs1 and Rs2 symbionts are genomically distinct in carbon and sulfur metabolism, respiration, and cell wall composition, among others. Differences between Rs1 and Rs2 and phylogenetic analysis of chemotaxis-related genes within individuals of symbiont Rs1 revealed the influence of the relative age of the whale fall environment and support possible local niche adaptation of 'free-living' lifestages. Future genomic examinations of other horizontally-propogated intracellular symbionts will likely enhance our understanding of the contribution of intraspecific symbiont diversity to the ecological diversification of the intact association, as well as the maintenance of host diversity.</P>

Epidemiologic Evidence of and Potential Mechanisms by Which Second-Hand Smoke Causes Predisposition to Latent and Active Tuberculosis

Xiyuan Bai,Shanae L. Aerts,Deepshikha Verma,Diane J. Ordway,Edward D. Chan 대한면역학회 2018 Immune Network Vol.18 No.3

Many studies have linked cigarette smoke (CS) exposure and tuberculosis (TB) infection and disease although much fewer have studied second-hand smoke (SHS) exposure. Our goal is to review the epidemiologic link between SHS and TB as well as to summarize the effects SHS and direct CS on various immune cells relevant for TB. PubMed searches were performed using the key words “tuberculosis” with “cigarette,” “tobacco,” or “second-hand smoke.” The bibliography of relevant papers were examined for additional relevant publications. Relatively few studies associate SHS exposure with TB infection and active disease. Both SHS and direct CS can alter various components of host immunity resulting in increased vulnerability to TB. While the epidemiologic link of these 2 health maladies is robust, more definitive, mechanistic studies are required to prove that SHS and direct CS actually cause increased susceptibility to TB.

Selective Unilateral Inner Hair Cell Injury: A Case Report

Jain Mehulla,Yasmin Shana,Prakash Sumanth Chakkere,Jain Chandni 대한청각학회 2023 Journal of Audiology & Otology Vol.27 No.4

Sensorineural hearing loss (SNHL) is known to be associated with lesions at various sites, including outer hair cell (OHC) and inner hair cell (IHC) injury, as well as auditory dyssynchrony or vestibulocochlear nerve tumors. Therefore, it is important to establish the differential diagnosis of SNHL, which however is particularly challenging in patients with unilateral SNHL. The test battery approach is effective for accurate diagnosis in such cases. In this report, we discuss the usefulness of the test battery approach to accurately detect the site of the lesion in a patient with unilateral hearing loss. A 14-year-9-month-old adolescent who observed decreased hearing sensitivity in the left ear accompanied by difficulty with understanding speech at a distance was diagnosed with unilateral hearing loss in the left ear. In this report, we describe a rare and diagnostically challenging case of unilateral SNHL in a patient with normal OHC function and selective injury to IHCs, which was diagnosed using a test battery approach.

Spatiotemporal Mapping Reveals Regional Gastrointestinal Dysfunction in mdx Dystrophic Mice Ameliorated by Oral L-arginine Supplementation

( Kristy Swiderski ),( Rebecka Bindon ),( Jennifer Trieu ),( Timur Naim ),( Shana Schokman ),( Mathusi Swaminathan ),( Anita J L Leembruggen ),( Elisa L Hill-yardin ),( Rene Koopman ),( Joel C Bornste 대한소화기 기능성질환·운동학회 2020 Journal of Neurogastroenterology and Motility (JNM Vol.26 No.1

Background/Aims Patients with Duchenne muscular dystrophy exhibit significant, ongoing impairments in gastrointestinal (GI) function likely resulting from dysregulated nitric oxide production. Compounds increasing neuronal nitric oxide synthase expression and/or activity could improve GI dysfunction and enhance quality of life for dystrophic patients. We used video imaging and spatiotemporal mapping to identify GI dysfunction in mdx dystrophic mice and determine whether dietary intervention to enhance nitric oxide could alleviate aberrant colonic activity in muscular dystrophy. Methods Four-week-old male C57BL/10 and mdx mice received a specialized diet either with no supplementation (control) or supplemented (1 g/kg/day) with L-alanine, L-arginine, or L-citrulline for 8 weeks. At the conclusion of treatment, mice were sacrificed by cervical dislocation and colon motility examined by spatiotemporal (ST) mapping ex vivo. Results ST mapping identified increased contraction number in the mid and distal colon of mdx mice on control and L-alanine supplemented diets relative to C57BL/10 mice (P < 0.05). Administration of either L-arginine or L-citrulline attenuated contraction number in distal colons of mdx mice relative to C57BL/10 mice. Conclusions GI dysfunction in Duchenne muscular dystrophy has been sadly neglected as an issue affecting quality of life. ST mapping identified regional GI dysfunction in the mdx dystrophic mouse. Dietary interventions to increase nitric oxide signaling in the GI tract reduced the number of colonic contractions and alleviated colonic constriction at rest. These findings in mdx mice reveal that L-arginine can improve colonic motility and has potential therapeutic relevance for alleviating GI discomfort, improving clinical care, and enhancing quality of life in Duchenne muscular dystrophy.

Nearshore waves and longshore sediment transport along Rameshwaram Island off the east coast of India

Gowthaman, Rajamanickam,Kumar, V. Sanil,Dwarakish, Gowdagere Siddaramaish,Shanas, P.R.,Jena, Basanta Kumar,Singh, Jai The Society of Naval Architects of Korea 2015 International Journal of Naval Architecture and Oc Vol.7 No.6

Wave-induced Longshore Sediment Transport (LST) play an important role in the dynamics of the Dhanushkodi sandspit located southeast of Rameshwaram. The LST along the Dhanushkodi coast is studied based on data collected simultaneously in Gulf of Mannar (GoM) and Palk Bay (PB) using directional waverider buoys. The numerical model REF/DIF1 was used to calculate the nearshore waves and the LST rate was estimated using three different formulae. The model validation was done based on the measured nearshore waves using InterOcean S4DW. Numerical model LITPACK was also used for simulating non-cohesive sediment transport and the LITLINE module was used to study the shoreline evolution over 5 years. Low net annual LST along PB (${\sim}0.01{\times}10^6m^3$) compared to the GoM region ($0.3{\times}10^6m^3$) were due to the weak waves. Accretion in the region led to growth of the Dhanushkodi sandspit by 65 m during the period 2010-2015.

Nearshore waves and longshore sediment transport along Rameshwaram Island off the east coast of India

Rajamanickam Gowthaman,V. Sanil Kumar,Gowdagere Siddaramaish Dwarakish,P.R. Shanas,Basanta Kumar Jena,Jai Singh 대한조선학회 2015 International Journal of Naval Architecture and Oc Vol.7 No.6

Wave-induced Longshore Sediment Transport (LST) play an important role in the dynamics of the Dhanushkodi sandspit located southeast of Rameshwaram. The LST along the Dhanushkodi coast is studied based on data collected simultaneously in Gulf of Mannar (GoM) and Palk Bay (PB) using directional waverider buoys. The numerical model REF/DIF1 was used to calculate the nearshore waves and the LST rate was estimated using three different formulae. The model validation was done based on the measured nearshore waves using InterOcean S4DW. Numerical model LITPACK was also used for simulating non-cohesive sediment transport and the LITLINE module was used to study the shoreline evolution over 5 years. Low net annual LST along PB (~ 0.01×106 m3) compared to the GoM region (0.3×106 m3) were due to the weak waves. Accretion in the region led to growth of the Dhanushkodi sandspit by 65 m during the period 2010-2015.