Microbiology Commons^™

The Role Of Genomic Versatility In Multi-Niche Preferences Of Escherichia Coli, Gitanjali Nandakafle

Electronic Theses and Dissertations

Escherichia coli strains are naturally present as either commensals or pathogens in the gastrointestinal tract of mammals and some other vertebrates. Until recently, it was assumed that E. coli are solely associated with the gut and are unable to survive outside of a host for a long period of time, the basis of its use as an indicator organism. Recent reports suggest that E. coli can become naturalized to several tropical, subtropical or temperate soils and aquatic environments, where they have been isolated repeatedly. Several studies have shown that these strains are capable of surviving and proliferating in the environment …

Investigating Antibiotic Resistance In Urban Agricultural Environment Using Phenotypic, Genomic, And Metagenomic Tools, Abdullah Ibn Mafiz

Wayne State University Dissertations

Urban agricultural environment can be an important reservoir of antibiotic resistance and have great food safety and public health indications. This study was to investigate antibiotic-resistant bacteria and antibiotic resistance genes in urban agricultural environment using phenotypic, whole genome sequencing, and metagenomic tools. Three urban community gardens from metro Detroit were studied in two phases.

First phase of this study recovered a total of 207 soil bacteria from 41 soil samples collected from an urban agricultural garden. The most prevalent antibiotic resistance phenotypes demonstrated by Gram-negative bacteria was the resistance to ampicillin (94.2%), followed by chloramphenicol (80.0%), cefoxitin (79.5%), gentamicin …

The Effect Of Short-Term Supplementation Of Potato Starch And Vsl#3 On The Large Intestines Of Male C57bl/6 Mice, Kaitlyn R. Merz

Wayne State University Theses

The microbiome is extremely complex and presumed to be involved in several biological processes. Dysbiosis is associated with development of several diseases, therefore, eubiosis is essential for prevention and treatment, possibly achieved through prebiotic or probiotic supplementation. The objective of this study was to establish effects of short-term supplementation on large intestine microbiota, pH and inflammatory cytokines. Large intestines of 21 day old C57BL/6 male mice that were given a control diet or supplemented with 10% potato starch or VSL#3 short-term, were analyzed for shifts in bacteria, pH, and inflammatory cytokine concentration. Large intestine digesta bacteria concentration differed from feces …

Characterizing The Roles Of Staphylococcus Aureus Secreted Factors In Virulence And Modulation Of Innate Immune Cell Activity, Cameron Harvey

Master's Theses

Staphylococcus aureus is a prominent human pathogen that is responsible for a massive burden on healthcare. This thesis takes two approaches to characterize how S. aureus secreted factors subvert the innate immune response. First, characterization of the integral membrane protease 1984 showed that it regulates secretion of a putative lytic transglycosylase, IsaA, which is implicated in virulence. My results suggest IsaA and 1984 are capable of modulating immune responses that result in enhanced heart colonization in vivo. In addition, recent studies have uncovered TLR-independent pathways that induce inflammatory responses after S. aureus insult. Therefore, I hypothesized the bacterium secretes factors …

Exploring The Short-Term Effects Of Probiotic And Prebiotic Supplementation On The Microbiota And Physiology Of Male C57bl/6 Mice, Miguel Angel Rivas

Wayne State University Theses

The gut microbiome may play a role in the development of chronic diseases like obesity, diabetes, and heart disease. Diets including prebiotics or probiotics can alter the abundance of gut bacterial groups and have subsequent health effects. In this study we wanted to establish a method for comparing the benefits of commercial supplements that alter the microbiota by monitoring fecal microbial profiles in male C57BL/6 mice (n = 24) exposed to 15 days of dietary supplementation. A probiotic diet (VSL#3) and a prebiotic diet (potato starch) were compared to a standard diet (n = 8 for each group). Microbial profiles …

Coordination Of Different Ligands To Copper(Ii) And Cobalt(Iii) Metal Centers Enhances Zika Virus And Dengue Virus Loads In Both Arthropod Cells And Human Keratinocytes, Shovan Dutta, Michael J. Celestine, Supreet Khanal, Alexis Huddleston, Colin Simms, Jessa Faye Arca, Amlam Mitra, Loree Heller, Piotr Kraj, Michael Ledizet, John F. Anderson, Girish Neelakanta, Alvin A. Holder, Hameeda Sultana

Biological Sciences Faculty Publications

Trace elements such as copper and cobalt have been associated with virus-host interactions. However, studies to show the effect of conjugation of copper(II) or cobalt(III) metal centers to thiosemicarbazone ligand(s) derived from either food additives or mosquito repellent such as 2-acetylethiazole or citral, respectively, on Zika virus (ZIKV) or dengue virus (serotype 2; DENV2) infections have not been explored. In this study, we show that four compounds comprising of thiosemicarbazone ligand derived from 2-acetylethiazole viz., (E)-N-ethyl-2-[1-(thiazol-2-yl)ethylidene]hydrazinecarbothioamide (acetylethTSC) (compound 1), a copper(II) complex with acetylethTSC as a ligand (compound 2), a thiosemicarbazone ligand-derived from citral (compound 3) and a cobalt(III) complex …

Cyclic Adenosine Monophosphate Signaling In Mycobacterium Tuberculosis : New Insights Into A Universal Second Messenger, Richard Mcpherson Johnson

Legacy Theses & Dissertations (2009 - 2024)

Despite being the focus of intense research for many years Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), remains the deadliest bacterial pathogen plaguing mankind today. Humans are the sole host and reservoir for Mtb, and Mtb has coevolved closely with its human host for thousands of years. Mtb currently infects over two billion people worldwide and over 1.5 million people die from TB each year, arguably making Mtb the most successful bacterial pathogen on the planet.

Investigation Of The Ms2 Bacteriophage Capsid As An Mri-Capable, Brain-Targeted Nanoparticle Platform, Stephanie M. Curley

Legacy Theses & Dissertations (2009 - 2024)

Novel methods are needed to traverse the blood-brain barrier (BBB) and deliver drugs to specific targets in the brain. To this end, MS2 bacteriophage was explored as a multifunctional transport and targeting vector. The MS2 capsid exterior was modified with two different targeting moieties for delivery across the BBB and targeting specific regions of interest in the brain. Successful modification of MS2 capsids with a brain targeting peptide and NMDAR2D-targeting antibody was confirmed by immunoblotting and fluorescence detection. To measure transport efficiency of MS2 particles across an in vitro BBB model, a highly sensitive RT-qPCR protocol was developed and implemented. …

Non-Canonicaly Recruited Tcrαβcd8Αα Iels Recognize Microbial Antigens, Lukasz Wojciech, Edyta Szurek, Michal Kuczma, Anna Cebula, Wessam R. Elhefnawy, Maciej Pietrzak, Grzegorz Rempala, Leszek Ignatowicz

Computer Science Faculty Publications

In the gut, various subsets of intraepithelial T cells (IELs) respond to self or non-self-antigens derived from the body, diet, commensal and pathogenic microbiota. Dominant subset of IELs in the small intestine are TCRαβCD8αα⁺ cells, which are derived from immature thymocytes that express self-reactive TCRs. Although most of TCRαβCD8αα⁺ IELs are thymus-derived, their repertoire adapts to microbial flora. Here, using high throughput TCR sequencing we examined how clonal diversity of TCRαβCD8αα⁺ IELs changes upon exposure to commensal-derived antigens. We found that fraction of CD8αα⁺ IELs and CD4⁺ T cells express identical …

Surveillance Of South Dakota Mosquito Abundance, Infection Rate, And Insecticide Susceptibility, Geoffrey P. Vincent

Electronic Theses and Dissertations

The aim of this dissertation was to survey and evaluate the abundance, infection rate, and insecticide susceptibility of mosquito fauna present in South Dakota. Mosquito surveillance has been conducted across South Dakota to record and track potential West Nile virus (WNV) vectors from 2004 to 2017. The nuisance mosquito Aedes vexans was found to be the most abundant species overall in the state and most abundant in many of the regions. The WNV vector, Culex tarsalis, was found to be the second most abundant mosquito and the most abundant vector mosquito across the state. However, geospatial variation did exist between …

Dissecting Rna Silencing Pathways In Sclerotinia Sclerotiorum, Pauline Mochama

Electronic Theses and Dissertations

RNA silencing, also known as RNA interference, is an essential mechanism in plants, animals and fungi that functions in gene regulation and defense against foreign nucleic acids. In fungi, RNA silencing has been shown to function primarily in defense against invasive nucleic acids. RNA-silencing- deficient fungi show increased susceptibility to virus infection. Plant pathogenic fungi also utilize RNA silencing to silence plant host immunity genes through the delivery of fungal small RNAs into plants. This cross-kingdom RNA silencing facilitates fungal infection of plants. Overall, these findings demonstrate the significant contributions of fungal RNA silencing pathways to fungal virulence and viral …

Replication, Virulence, And Pathogenesis Of Influenza Viruses, Chithra Chembil Sreenivasan

Electronic Theses and Dissertations

Influenza D virus (IDV) is a novel influenza virus that infects cattle and swine, with cattle as its primary host species. The goal of our first study was to investigate the replication and transmission of bovine IDV in guinea pigs. Following direct intranasal inoculation of animals, the virus was detected in nasal washes of infected animals during the first 7 days post-infection. High viral titers were obtained from nasal turbinates and lung tissues of directly inoculated animals. Further, bovine IDV was able to transmit from the infected guinea pigs to sentinel animals by means of contact and not by aerosol …

Waterborne Disease Reduction Using Evidence-Based Microbiology Verification In Lower Nyakach, Kenya, Richard R. Blodgett

Walden Dissertations and Doctoral Studies

Waterborne diseases continue to plague the poorest people in low-income countries and are estimated to cause 4,600,000 acute incidents of diarrhea resulting in over 2,000 deaths daily. A major challenge is performing microbiology tests to monitor drinking water quality. Friends of the Old (FOTO) implemented a novel strategy using evidence-based microbiology to educate communities about the relationship between contaminated water and disease. Two commercially available tests for E.coli, adapted for fieldwork, provided easily interpreted results of contamination that correlate with WHO's disease risk categories. Simple and effective household water treatment options 'solar pasteurization and/or chlorination' were provided to all 14,400 …

A Link Between Gut Microbes & Depression: Microbial Activation Of The Human Kynurenine Pathway, Christina Cobb

CMC Senior Theses

Our gut microbiota is involved in human development, nutrition, and the pathogenesis of gut disorders, but has more recently been implicated as a possible mechanism in the pathophysiology of several brain disorders, including disorders of mood and affect, such as depression. Researchers have referred to this dynamic, bidirectional signaling pathway between the gut and the brain as the “gut-brain axis.” However, most research on this axis has been limited to rodent studies, and there has been little insight into the mechanism behind it. I propose that the kynurenine pathway, where tryptophan is converted to kynurenine, is a compelling mechanism mediating …

Immunization By Radiotherapy: Enhancing An Immune-Mediated Abscopal Effect, Amy Steffen

Biology and Microbiology Graduate Students Plan B Research Projects

Radiotherapy aims to destroy tumors by inducing DNA damage in their cells at the local irradiation site. Its immune-mediated systemic effects, called abscopal effect, has shown to enhance anti-tumor immunity when combined with immune therapies and thus, have gained attention by researchers and clinicians to investigate. Below is a summary of the fundamentals of cancer and the immune system’s response to it, as well as the changes in the phenotype and microenvironment of tumor cells after exposure to radiation. Impacts of the abscopal effect and the induction of effective antitumor immunity with various immune therapy strategies will be outlined. The …

Increasing The Clinical Efficacy Of Radiotherapeutics For Solid Tumors By Inhibition Of Hypoxia Inducible Factor-1a, Austin Levi Walz

Biology and Microbiology Graduate Students Plan B Research Projects

Radiotherapy is commonly used in a variety of tumor types and is effective in control of long term progression and may be curative under certain circumstances. Radiotherapeutics have been shown to be the single most effective therapeutic for cancer and only account for 5% of the total cost. However, treatment of cells with radiation causes the tumor microenvironment to undergo changes and leads to cycles of hypoxia inside the tumor which allows for the cell to undergo angiogenesis, metastasize and may lead to repopulation of the tumor. Current systemic chemotherapeutics typically have an additive toxicity due to the unintended targeting …

A Review Of Multiple Sclerosis Treatments: Interferon Beta, Glatiramer Acetate, Fingolimod, And Natalizumab, Ryan Golden

Biology and Microbiology Graduate Students Plan B Research Projects

Multiple Sclerosis (MS) is an autoimmune disease in which the body’s own immune system works to demyelinate the myelin sheaths in the central nervous system. The beginning of the review will concentrate on the history of MS while also describing how MS, the disease, differs from that of normal immune responses. The review then shifts to the four different stages of MS and how to differentiate between the stages, since the treatment options are often dependent on the stage of MS that the patient is in. The main focus of this review is to take an in depth look on …

A Biological Review Of Mental Illness: An Overview Of Genetics And Pathophysiology Of Schizophrenia, Major Depression, And Addiction, Christopher R. Angerhofer

Biology and Microbiology Graduate Students Plan B Research Projects

Novel approaches in understanding mental illness present solutions to current issues in treatment and diagnosis. With advancements in genetics and neurology, the etiology and pathophysiology of mental illness is slowly unwrapping. In discovering biomarkers for depression, addiction, and schizophrenia, the precision for preventing, diagnosing, and treating these disorders increases. The aim of this paper is to review current research for addiction, major depression, and schizophrenia in genetics and physiology, while also clarifying the need for reclassifying mental illness as diseases with a pathophysiological basis, not syndromal, idiopathic disorders. Mental illness is dynamic in that it encompasses both environmental and biological …

Mild Traumatic Brain Injuries And Cte: A Review Highlighting The Connection Between The Two, Leandre Kennedy

Biology and Microbiology Graduate Students Plan B Research Projects

Chronic Traumatic Encephalopathy (CTE) is a traumatic brain injury based disease that is garnering a lot of attention in the United States. The purpose of this paper is to conduct an extensive review of the information available about the condition. Recently there has been a limited amount of published information and treatment opportunities are rare since the only way of diagnosing has come post mortem. Various literary reviews and experiments were analyzed for appropriate information regarding CTE’s pathology and treatments and only peer reviewed published works were allowed in this paper. This resulted in promising information about the disease and …

The Response Of Unpolarized Macrophages (Raw 264.7)/Keratinocytes (Pam-212) Monolayer And Co-Culture System To Herpes Simplex Virus Type 1 (Hsv-1) Replication During The Infection., Fahad Mohammed Alradi

Browse all Theses and Dissertations

Keratinocytes and neurons cells are the main target for Herpes Simplex Virus Type 1 (HSV-1) invasion. Moreover, keratinocytes are the most abundant cell types in the epidermis layer in the skin. Therefore, they are the first cells to encounter HSV-1 in the primary infection. Next, the virus reaches the nerve endings and is transferred to neuronal cells as a result from the primary infection. In between these two events, innate immune cells including monocytes and macrophages response is activated and recruited to the infection site. In this study, keratinocytes (PAM-212) and murine macrophage (RAW 264.7) cell lines were utilized to …

Virus Production And Cell Viability Of Hsv-1-Infected Murine Keratinocytes (Hel-30) Co-Cultured With Murine Macrophages (Raw 264.7), Barry Graffagna

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Keratinocytes are the most abundant type of cell in the outer layer of skin, the epidermis, and provide barrier against pathogens from invading. However, Herpes Simplex Virus Type 1 (HSV-1) targets these keratinocytes for infection, and later infects neurons to establish lifelong latency. The keratinocytes stimulate the innate immune system to engage and to destroy the virus. Among the cells of the innate immune system to respond to the viral invasion is the macrophage. In this study, RAW 264.7 macrophage and HEL-30 keratinocyte monolayers were challenged in vitro with HSV-1 at a multiplicity of infection (MOI) of 0.1 to investigate …

Marine Bioactives From Saccharina Latissima, Orlaith O'Connell

Masters

Due to rapid global urbanization and therefore increased adoption of a 'Westernized' lifestyle, including decreased physical activity and increased consumption of highly processed and refined foods with a high sugar, fat and salt content, prevalence of gastrointestinal disorders are on the rise. Inflammatory bowel disease (IBD) in particular is closely associated with this type of lifestyle. IBD is a term used to describe chronic inflammatory conditions which affects all or parts of the gastrointestinal tract. It includes conditions such as Crohn's Disease, which affects all the gastrointestinal tract and Ulcerative Colitis which mainly affects the colan. Due to the role …

Impacts Of Trace Metal Pollution, Urbanization And Aquifer Recharge On Spokane River Macroinvertebrates, Carolyn K. Connelly

EWU Masters Thesis Collection

This study analyzed macroinvertebrate communities of the Spokane River to determine: 1) accumulation of toxic trace metals in macroinvertebrate tissue, 2) effects of aquifer recharge, and 3) impact of urbanization. I predicted that aquifer inflows of cold, clean water would mitigate effects of pollution, and that reaches above the City of Spokane would be less negatively affected by urbanization; both were unsupported. I also predicted that effects of toxic trace metals would decrease within distance downstream; this prediction was supported. I sampled 12 riffles of the Spokane River between the Washington/Idaho border and Riverside State Park in late summer 2010. …

Monitoring The Influx Of Marine Derived Nitrogen And Characterizing Soil Food Webs Of Riparian Zones Of The Elwha River Watershed, Wa, Usa., Wendal R.H. Kane

EWU Masters Thesis Collection

Nitrogen is often the most limiting nutrient to productivity in terrestrial ecosystems, and can have large effects on ecosystem processes. Two sources of nitrogen to Pacific Northwest riparian areas are marine derived nitrogen (MDN) via anadromous pacific salmon and symbiotic nitrogen fixation via Alnus rubra. The recent removal of two large dams on the Elwha River, WA, opened up ~60 km of previously inaccessible river habitat for pacific salmon. I used naturally abundant stable nitrogen isotopes (denoted as ‰ δ15N) to establish baseline data to monitor the influx of MDN to riparian zones of Elwha River tributaries, post dam removal. …

Relationships Between Factors Influencing Biofilm Formation And Pathogen Retention In Complex Rhizosphere Microbial Communities, Aaron Coristine

Theses and Dissertations (Comprehensive)

Riparian wetlands are unique habitats facilitating all forms of life. The riverbanks of these environments provide ideal conditions for bacteria, plants, and higher organisms. Of particular interest to this research was the variation in microbial community structure at high, intermediate and poor water quality impacted areas. Assessing the capabilities of plants to retain microbial pathogens was identified. Root systems and corresponding soil are ideal locations for bacterial deposition, resulting in attachment at these areas. Biofilm production in these regions is important for long-term establishment, leading to persistence and potential naturalization. Opportunistic pathogens originating from mammalian fecal matter are introduced into …

Bioinformatic Interrogation Of Phosphonate Tailoring Pathways, Monica Papinski

Theses and Dissertations (Comprehensive)

Phosphonates represent an underexploited class of natural products despite their tremendous potential for use in medicine and agriculture. Even less characterized are phosphonate-containing macromolecules such as cell wall lipids and glycans, distinguished by a P-C bond known to provide stability towards hydrolysis. Despite some progress made in revealing cell wall phosphonate tailoring (Pnt) pathways, several barriers impede the discovery and characterization of novel phosphonate biosynthetic pathways. Specifically, a large diversity of gene composition and arrangement is evident surrounding key genes established to participate in phosphonate tailoring pathways, which are identified alongside the presence of the ppm gene encoding the P-C …

Metabolic Engineering Of Synechococcus Elongatus Pcc 7942 For Mycosporine-2-Glycine Production Under Salt Stress Condition, Panwad Pingkhanont

Chulalongkorn University Theses and Dissertations (Chula ETD)

ไมโครสปอรีน-ไลก์ อะมิโน แอซิด (MAAs) เป็นกลุ่มของสารเมแทบอไลต์ทุติยภูมิ สังเคราะห์โดยจุลินทรีย์และสาหร่ายหลายชนิด สารกลุ่มนี้มีหน้าที่สำคัญในการคัดกรองรังสียูวี และยังมีหน้าที่อื่นๆ ได้แก่ การต้านอนุมูลอิสระ ปกป้องเซลล์จากภาวะเครียด และควบคุมการออสโมซิส โดยไมโครสปอรีน-2-ไกลซีน (M2G) เป็นหนึ่งในสารกลุ่ม MAAs ที่มีความสามารถในการต้านอนุมูลอิสระมากกว่าสารอื่นๆ ในกลุ่มเดียวกัน ดังนั้นจึงเป็นที่สนใจที่จะเพิ่มการผลิต M2G เพื่อนำไปประยุกต์ใช้ในอุตสาหกรรมความงาม และเวชสำอาง ในการศึกษานี้ประสบความสำเร็จในการแสดงออกของยีนในชีวสังเคราะห์ M2G (Ap3858-3855) จาก Aphanothece halophytica ในไซยาโนแบคทีเรียน้ำจืด Synechococcus elongatus PCC 7942 จากการวิเคราะห์การถอดรหัสของยีน Ap3858-3855 พบว่า ยีนทั้ง 4 ยีนนี้เป็น monocistronic mRNA heterologous expression ของยีน Ap3858-3855 ใน S. elongatus พบว่าทุกยีนมีการแสดงออกมากขึ้นภาวะเครียดจากเกลือ NaCl ยีน Ap3857 แสดงออกเพิ่มมากที่สุด 2.39 ± 0.25 เท่า และภายใต้ภาวะเครียดจากเกลือ KCl ยีน Ap3856 แสดงออกเพิ่มมากที่สุด 3.70 ± 0.35 เท่า ระดับการแสดงออกของยีนที่เกี่ยวข้องกับภาวะเครียดออกซิเดชั่น (sodB, cat และ tpxA) ในเซลล์แสดงออก พบว่าภายใต้ภาวะเครียดจากเกลือ NaCl มีเพียงยีน tpxA แสดงออกมากขึ้น 4.58 ± 0.58 เท่า ขณะที่ภาวะเครียดจากเกลือ KCl กระตุ้นการแสดงออกของ sodB และ tpxA 4.09 ± 0.86 และ 11.81 ± 1.02 เท่า ตามลำดับ ส่วนการแสดงออกของยีนที่เกี่ยวข้องกับสารออสโมไลท์ ได้แก่ Synpcc7942_0808 และ …

Characterizing Immune Response To Hiv-1 Infection In Bicd2-Knockout Cells, Omar Abdel-Rahim

Master's Theses

An important part of the HIV-1 infection cycle is the attachment of the intracellular viral core to the host microtubule network, facilitated by attachment of the viral capsid to cargo adaptor proteins. One such cargo adaptor is Bicaudal D Homolog Protein 2 (BICD2). BICD2 can attach to both the HIV-1 capsid and the dynein/dynactin complex and facilitate the trafficking of the viral core towards the host nucleus. Removal of BICD2 can disrupt this viral translocation, resulting in an elevated immune response that impairs productive HIV-1 infection. In my research, we investigated what viral particles are detected in the absence of …

Effects Of Voluntary Physical Rehabilitation On Neurogenesis In Svz And Functional Recovery After Ischemic Stroke, Anuranjani Balakrishnan

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Stroke is the leading cause of long-term disability and 87% of all strokes are due to ischemic strokes. In this current study, we examined whether voluntary physical rehabilitation can influence neurogenesis (measured by Doublecortin) in the subventricular zone and show improved motor functional recovery in 10-12 month female rats after ischemia. We saw a significant increase in the neurogenesis (measured by doublecortin) of all three regions (anterior, middle and posterior) of SVZ in the rehab animals compared to control group when using a two-way variance ANOVA test, although we were unable to see significant differences in paired t-tests of similar …

Size-Dependent Inhibitory Effects Of Antibiotic Drug Nanocarriers Against Pseudomonas Aeruginosa, Feng Ding, Preeyaporn Songkiatisak, Pavan Kumar Cherukuri, Tao Huang, Xiao-Hong Nancy Xu

Chemistry & Biochemistry Faculty Publications

Multidrug membrane transporters (efflux pumps) are responsible for multidrug resistance (MDR) and the low efficacy of therapeutic drugs. Noble metal nanoparticles (NPs) possess a high surface-area-to-volume ratio and size-dependent plasmonic optical properties, enabling them to serve both as imaging probes to study sized-dependent MDR and as potential drug carriers to circumvent MDR and enhance therapeutic efficacy. To this end, in this study, we synthesized three different sizes of silver nanoparticles (Ag NPs), 2.4 ± 0.7, 13.0 ± 3.1, and 92.6 ± 4.4 nm, functionalized their surface with a monolayer of 11-amino-1-undecanethiol (AUT), and covalently conjugated them with antibiotics (ofloxacin, Oflx) …