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Full-Text Articles in Organisms

Oxidative Stress Strongly Restricts The Effect Of Codon Choice On The Efficiency Of Protein Synthesis In Escherichia Coli, Lorenzo Eugenio Leiva, Sara Elgamal, Sebastian A. Leidel, Omar Orellana, Michael Ibba, Assaf Katz Nov 2022

Oxidative Stress Strongly Restricts The Effect Of Codon Choice On The Efficiency Of Protein Synthesis In Escherichia Coli, Lorenzo Eugenio Leiva, Sara Elgamal, Sebastian A. Leidel, Omar Orellana, Michael Ibba, Assaf Katz

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Introduction

The response of enterobacteria to oxidative stress is usually considered to be regulated by transcription factors such as OxyR and SoxR. Nevertheless, several reports have shown that under oxidative stress the levels, modification and aminoacylation of tRNAs may be altered suggesting a role of codon bias in regulation of gene expression under this condition.

Methods

In order to characterize the effects of oxidative stress on translation elongation we constructed a library of 61 plasmids, each coding for the green fluorescent protein (GFP) translationally fused to a different set of four identical codons.

Results

Using these reporters, we observed that …


Emergence Of A Multidrug-Resistant And Virulent Streptococcus Pneumoniae Lineage Mediates Serotype Replacement After Pcv13: An International Whole-Genome Sequencing Study, Stephanie W. Lo, Kate Mellor, Robert Cohen, Alba Redin Alonso, Sophie Belman, Narender Kumar, Paulina A. Hawkins, Rebecca A. Gladstone, Sadia Shakoor, Muhammad Imran Nisar Oct 2022

Emergence Of A Multidrug-Resistant And Virulent Streptococcus Pneumoniae Lineage Mediates Serotype Replacement After Pcv13: An International Whole-Genome Sequencing Study, Stephanie W. Lo, Kate Mellor, Robert Cohen, Alba Redin Alonso, Sophie Belman, Narender Kumar, Paulina A. Hawkins, Rebecca A. Gladstone, Sadia Shakoor, Muhammad Imran Nisar

Department of Pathology and Laboratory Medicine

Background: Serotype 24F is one of the emerging pneumococcal serotypes after the introduction of pneumococcal conjugate vaccine (PCV). We aimed to identify lineages driving the increase of serotype 24F in France and place these findings into a global context.
Methods: Whole-genome sequencing was performed on a collection of serotype 24F pneumococci from asymptomatic colonisation (n=229) and invasive disease (n=190) isolates among individuals younger than 18 years in France, from 2003 to 2018. To provide a global context, we included an additional collection of 24F isolates in the Global Pneumococcal Sequencing (GPS) project database for analysis. A Global Pneumococcal Sequence Cluster …


Frequency Of Bystander Exposure To Antibiotics For Enteropathogenic Bacteria Among Young Children In Low-Resource Settings, Elizabeth T. Rogawski Mcquade, Stephanie A. Brennhofer, Sarah E. Elwood, Timothy L. Mcmurry, Joseph A. Lewnard, Estomih R. Mduma, Sanjaya Shrestha, Najeeha Talat Iqbal, Pascal O. Bessong, Gagandeep Kang Sep 2022

Frequency Of Bystander Exposure To Antibiotics For Enteropathogenic Bacteria Among Young Children In Low-Resource Settings, Elizabeth T. Rogawski Mcquade, Stephanie A. Brennhofer, Sarah E. Elwood, Timothy L. Mcmurry, Joseph A. Lewnard, Estomih R. Mduma, Sanjaya Shrestha, Najeeha Talat Iqbal, Pascal O. Bessong, Gagandeep Kang

Department of Paediatrics and Child Health

Children in low-resource settings carry enteric pathogens asymptomatically and are frequently treated with antibiotics, resulting in opportunities for pathogens to be exposed to antibiotics when not the target of treatment (i.e., bystander exposure). We quantified the frequency of bystander antibiotic exposures for enteric pathogens and estimated associations with resistance among children in eight low-resource settings. We analyzed 15,697 antibiotic courses from 1,715 children aged 0 to 2 y from the MAL-ED birth cohort. We calculated the incidence of bystander exposures and attributed exposures to respiratory and diarrheal illnesses. We associated bystander exposure with phenotypic susceptibility of E. coli isolates in …


Cmv And Ebv Co-Infection In Hiv-Infected Children: Infection Rates And Analysis Of Differential Expression Of Cytokines In Hiv Mono- And Hiv-Cmv-Ebv Co-Infected Groups, Fizza Nazim, Hammad Afzal Kayani, Aspara Ali Nathwani, Fatima Mir, Syed Hani Abidi Aug 2022

Cmv And Ebv Co-Infection In Hiv-Infected Children: Infection Rates And Analysis Of Differential Expression Of Cytokines In Hiv Mono- And Hiv-Cmv-Ebv Co-Infected Groups, Fizza Nazim, Hammad Afzal Kayani, Aspara Ali Nathwani, Fatima Mir, Syed Hani Abidi

Department of Biological & Biomedical Sciences

Background: CMV and EBV co-infections can affect the HIV disease progression by modulating the immune system. The disease dynamics can differ in HIV-positive adults and children. In Pakistan, HIV is rapidly expanding, especially in children; however, the prevalence of CMV and EBV co-infection and the effect on immune modulation in HIV-positive children are not known. This study aimed to bridge this gap by estimating the rate of active CMV and EBV co-infection in HIV-positive children, followed by the analysis of differential expression of cytokines in HIV mono- and HIV/CMV/EBV co-infected children.
Methods: DNA samples from 319 HIV-positive children, previously recruited …


Incidence Of Typhoid And Paratyphoid Fever In Bangladesh, Nepal, And Pakistan: Results Of The Surveillance For Enteric Fever In Asia Project, Mohammad Tahir Yousafzai, Sadia Shakoor, Irum Fatima Dehraj, Junaid Mehmood, Rozina Thobani, Aneeta Hotwani, Najeeb Rehman, Seema Irfan, Abdul Momin Kazi, Mohammed J. Hunzai Jul 2022

Incidence Of Typhoid And Paratyphoid Fever In Bangladesh, Nepal, And Pakistan: Results Of The Surveillance For Enteric Fever In Asia Project, Mohammad Tahir Yousafzai, Sadia Shakoor, Irum Fatima Dehraj, Junaid Mehmood, Rozina Thobani, Aneeta Hotwani, Najeeb Rehman, Seema Irfan, Abdul Momin Kazi, Mohammed J. Hunzai

Department of Paediatrics and Child Health

Background: Precise enteric fever disease burden data are needed to inform prevention and control measures, including the use of newly available typhoid vaccines. We established the Surveillance for Enteric Fever in Asia Project (SEAP) to inform these strategies.
Methods: From September, 2016, to September, 2019, we conducted prospective clinical surveillance for Salmonella enterica serotype Typhi (S Typhi) and Paratyphi (S Paratyphi) A, B, and C at health facilities in predetermined catchment areas in Dhaka, Bangladesh; Kathmandu and Kavrepalanchok, Nepal; and Karachi, Pakistan. Patients eligible for inclusion were outpatients with 3 or more consecutive days of fever in the last 7 …


Resolving The Repression Pathway Of Virulence Gene Hila In Salmonella, Alexandra King, Lon Chubiz Phd, Brenda Pratte, Lauren Daugherty Jun 2022

Resolving The Repression Pathway Of Virulence Gene Hila In Salmonella, Alexandra King, Lon Chubiz Phd, Brenda Pratte, Lauren Daugherty

Undergraduate Research Symposium

Salmonella is a relatively abundant, virulent species of bacteria that is most known for spreading gastrointestinal diseases through food. These illnesses result in approximately 1.35 million infections, including over 25,000 hospitalizations each year, in the U.S. alone (CDC.gov). As antibiotic resistance becomes an increasingly urgent public health problem, the importance of developing alternative treatment methods is only becoming more crucial. One of the genes responsible for this virulence is known as hilA. HilA is the main transcriptional regulator of Salmonella Pathogenicity Island-1 gene (UniProt). SPI-1 plays an important role in the invasion of Salmonella into epithelial cells. The proteins encoded …


Effect Of Bovine Lactoferrin On Seroconversion Following Polio Vaccine Administration In Children: Protocol For A Double-Blinded Randomised Controlled Trial, Atif Habib, Sidrah Nausheen, Shanila Nooruddin, Tooba Javed, Tariq Samejo, Amjad Hussain, Suneeta Namdave, Sehrish Amirali, Muhammad Umer, Lumaan Sheikh May 2022

Effect Of Bovine Lactoferrin On Seroconversion Following Polio Vaccine Administration In Children: Protocol For A Double-Blinded Randomised Controlled Trial, Atif Habib, Sidrah Nausheen, Shanila Nooruddin, Tooba Javed, Tariq Samejo, Amjad Hussain, Suneeta Namdave, Sehrish Amirali, Muhammad Umer, Lumaan Sheikh

Department of Paediatrics and Child Health

Introduction: The oral polio vaccine (OPV) has substantial results in eliminating wild poliovirus and the vaccine of choice in polio eradication. However, the mucosal immunity induced by the OPV is still uncertain. Literature has shown that bovine lactoferrin (BLF) is a safe and useful protein found in cow's milk with extraordinary antimicrobial, antiviral, antiinflammatory and immune-modulatory functions that help children's gut to fight against micro-organisms like poliovirus. However, limited data exist regarding the effect of BLF on polio vaccine immune response. The primary objective is to evaluate the effect of BLF in enhancing mucosal and humoral immunity in children following …


The Discovery And Analysis Of Mycobacteriophage “Rita”, Anna Fakhri Apr 2022

The Discovery And Analysis Of Mycobacteriophage “Rita”, Anna Fakhri

Chemistry & Biochemistry Student Scholarship

Anna Fakhri ’24
Major: Biochemistry
Faculty Mentor: Dr. Kathleen Cornely, Chemistry and Biochemistry

Mycobacteriophage “Rita” was isolated on Mycobacterium smegmatis mc2155 from an enriched soil sample from North Easton, Massachusetts. As Rita infects Mycobacterium smegmatis, further study of the phage was completed in order to determine its ability to be utilized in phage therapy for infections caused by pathogenic Mycobacterium, such as Mycobacterium tuberculosis and Mycobacterium abscessus. Once isolated, the phage DNA was analyzed through PCR to determine the phage belonged to cluster F and subcluster F1. The phage DNA was sequenced, and a genome annotation was completed. The annotation …


Predominantly Methicillin-Susceptible S. Aureus Bacteria Found In Csp Students’ S. Aureus Strains, Roma Ambo Apr 2022

Predominantly Methicillin-Susceptible S. Aureus Bacteria Found In Csp Students’ S. Aureus Strains, Roma Ambo

Research and Scholarship Symposium Posters

Positive Staphylococcus aureus strains from CSP students were tested for methicillin resistance (MRSA) using the Kirby-bauer assay. Kirby-bauer assay technique was used to determine the sensitivity of staphylococcus aureus bacteria against oxacillin. MRSA infection is the result of a bacteria that has built resistance against the antibiotics used to treat staph infections. The results of this experiment concludes that majority of the strains tested are methicillin-susceptible S. aureus (MSSA).


Characterisation Of Drug-Resistant Mycobacterium Tuberculosis Mutations And Transmission In Pakistan, Gary Napier, Anwar Sheed Khan, Abdul Jabbar, Muhammad Tahir Khan, Sajid Ali, Muhammad Qasim, Noor Mohammad, Rumina Hasan, Zahra Hasan, Susana Campino Apr 2022

Characterisation Of Drug-Resistant Mycobacterium Tuberculosis Mutations And Transmission In Pakistan, Gary Napier, Anwar Sheed Khan, Abdul Jabbar, Muhammad Tahir Khan, Sajid Ali, Muhammad Qasim, Noor Mohammad, Rumina Hasan, Zahra Hasan, Susana Campino

Department of Pathology and Laboratory Medicine

Tuberculosis, caused by Mycobacterium tuberculosis, is a high-burden disease in Pakistan, with multi-drug (MDR) and extensive-drug (XDR) resistance, complicating infection control. Whole genome sequencing (WGS) of M. tuberculosis is being used to infer lineages (strain-types), drug resistance mutations, and transmission patterns-all informing infection control and clinical decision making. Here we analyse WGS data on 535 M. tuberculosis isolates sourced across Pakistan between years 2003 and 2020, to understand the circulating strain-types and mutations related to 12 anti-TB drugs, as well as identify transmission clusters. Most isolates belonged to lineage 3 (n = 397; 74.2%) strain-types, and were MDR (n = …


Urinary Incontinence: Understanding The Silent Plight Of Women, Yasmin Nadeem Parpio, Anmol Minaz, Sonia Ijaz Haider Apr 2022

Urinary Incontinence: Understanding The Silent Plight Of Women, Yasmin Nadeem Parpio, Anmol Minaz, Sonia Ijaz Haider

School of Nursing & Midwifery

Urinary incontinence (UI) is defined as the complaint of involuntary loss of urine. UI affects both men and women but is more common in women. It has been identified as a World Health Organization priority. The burden related to UI at local, national, and global levels is huge and its impact in terms of physical, social, mental, and financial aspects makes it a concerning issue. However, there exist several barriers in terms of knowledge and attitude in seeking healthcare among women experiencing UI. This calls upon a multi-disciplinary approach involving professionals from different disciplines and tackling it with collaborative and …


A Streptococcus Pneumoniae Lineage Usually Associated With Pneumococcal Conjugate Vaccine (Pcv) Serotypes Is The Most Common Cause Of Serotype 35b Invasive Disease In South Africa, Following Routine Use Of Pcv, Kedibone M. Ndlangisa, Mignon Du Plessis, Stephani Lo, Linda De Gouveia, Chrispin Chaguza, Martin Antonio, Brenda Kwambana-Adams, Jennifer Cornick, Dean B. Everett, Sadia Shakoor Apr 2022

A Streptococcus Pneumoniae Lineage Usually Associated With Pneumococcal Conjugate Vaccine (Pcv) Serotypes Is The Most Common Cause Of Serotype 35b Invasive Disease In South Africa, Following Routine Use Of Pcv, Kedibone M. Ndlangisa, Mignon Du Plessis, Stephani Lo, Linda De Gouveia, Chrispin Chaguza, Martin Antonio, Brenda Kwambana-Adams, Jennifer Cornick, Dean B. Everett, Sadia Shakoor

Department of Pathology and Laboratory Medicine

Pneumococcal serotype 35B is an important non-conjugate vaccine (non-PCV) serotype. Its continued emergence, post-PCV7 in the USA, was associated with expansion of a pre-existing 35B clone (clonal complex [CC] 558) along with post-PCV13 emergence of a non-35B clone previously associated with PCV serotypes (CC156). This study describes lineages circulating among 35B isolates in South Africa before and after PCV introduction. We also compared 35B isolates belonging to a predominant 35B lineage in South Africa (GPSC5), with isolates belonging to the same lineage in other parts of the world. Serotype 35B isolates that caused invasive pneumococcal disease in South Africa in …


Etiology, Clinical Characteristics, And Outcome Of Infective Endocarditis: 10-Year Experience From A Tertiary Care Center In Pakistan, Sara Salim Ali, Imran Ahmed Qureshi, Ahmed Ayaz, Ainan Arshad, Awais Farhad, Bushra Jamil, Muhammad Rizwan Sohail Mar 2022

Etiology, Clinical Characteristics, And Outcome Of Infective Endocarditis: 10-Year Experience From A Tertiary Care Center In Pakistan, Sara Salim Ali, Imran Ahmed Qureshi, Ahmed Ayaz, Ainan Arshad, Awais Farhad, Bushra Jamil, Muhammad Rizwan Sohail

Medical College Documents

This study was conducted to assess the clinical characteristics, causative agents, complications, and outcomes of infective endocarditis (IE) among patients presenting to our tertiary care center over the last decade. This retrospective cohort study included all adult patients admitted to the Aga Khan University Hospital with the diagnosis of IE over a ten-year period from 2010 to 2020. Outcomes variables included complications during hospitalization, surgical intervention, mortality, and length of stay. We identified a total of 305 cases out of which 176 (58%) were males and 129 (42%) were females. The mean age of the patients was 46.9±18.8 years. 95 …


Catheter-Associated Urinary Tract Infections: Patient Characteristics, Treatment, And Clinical Outcomes In One South Texas Acute Care Hospital, Kimberly A. Ambrosini, Jose Campo Maldonado Feb 2022

Catheter-Associated Urinary Tract Infections: Patient Characteristics, Treatment, And Clinical Outcomes In One South Texas Acute Care Hospital, Kimberly A. Ambrosini, Jose Campo Maldonado

MEDI 9331 Scholarly Activities Clinical Years

Background: Catheter-associated urinary tract infections (CA-UTIs) account for 40 percent of nosocomial infections worldwide. Their elimination is at the forefront of quality improvement in one South Texas acute care hospital.

Methods: Over a period of 6 months, five CA-UTIs occurred in one South Texas acute care hospital. These cases were identified via regular surveillance by Infection Prevention staff and the Laboratory Department of the hospital. This research reviews patient age, sex, length of stay, bacteria contracted, appropriate antibiotic use, patient characteristics, and overall outcomes.

Results: Between the months of July and December 2021, 5 CAUTIs were contracted. Patients …


Contact Dermatitis Due To Personal Protective Equipment Use And Hygiene Practices During The Covid-19 Pandemic: A Systematic Review Of Case Reports, Zouina Sarfraz, Azza Sarfraz, Muzna Sarfraz, Miguel Felix, Jonathan A. Bernstein, Luz Fonacier, Ivan Cherrez-Ojeda Feb 2022

Contact Dermatitis Due To Personal Protective Equipment Use And Hygiene Practices During The Covid-19 Pandemic: A Systematic Review Of Case Reports, Zouina Sarfraz, Azza Sarfraz, Muzna Sarfraz, Miguel Felix, Jonathan A. Bernstein, Luz Fonacier, Ivan Cherrez-Ojeda

Department of Paediatrics and Child Health

Background: Prolonged use of personal protective equipment (PPE) may lead to contact dermatitis during the coronavirus disease 19 (COVID-19) pandemic. This paper aims to identify the causative factors of contact dermatitis from PPE and hygiene practices.
Methods: The search was conducted adhering to PRISMA 2020 guidelines. A Delphi process was employed to ensure that the aims of this study were met. PubMed and Web of Science databases were systematically searched through September 12, 2021, using search terms: Contact dermatitis, case report, covid-19. The findings were tabulated as author/year, gender, age, presentation, cause, dermatological diagnosis, testing modality, provided treatment, symptom resolution …


Distribution Of Serotypes And Antibiotic Resistance Of Invasive Pseudomonas Aeruginosa In A Multi-Country Collection, Shamima Nasrin, Nicolas Hegerle, Shaichi Sen, Joseph Nkeze, Sunil Sen, Jasnehta Permala-Booth, Myeongjin Choi, James Sinclair, Milagritos D. Tapia, Sadia Shakoor Jan 2022

Distribution Of Serotypes And Antibiotic Resistance Of Invasive Pseudomonas Aeruginosa In A Multi-Country Collection, Shamima Nasrin, Nicolas Hegerle, Shaichi Sen, Joseph Nkeze, Sunil Sen, Jasnehta Permala-Booth, Myeongjin Choi, James Sinclair, Milagritos D. Tapia, Sadia Shakoor

Department of Pathology and Laboratory Medicine

Background: Pseudomonas aeruginosa is an opportunistic pathogen that causes a wide range of acute and chronic infections and is frequently associated with healthcare-associated infections. Because of its ability to rapidly acquire resistance to antibiotics, P. aeruginosa infections are difficult to treat. Alternative strategies, such as a vaccine, are needed to prevent infections. We collected a total of 413 P. aeruginosa isolates from the blood and cerebrospinal fluid of patients from 10 countries located on 4 continents during 2005-2017 and characterized these isolates to inform vaccine development efforts. We determined the diversity and distribution of O antigen and flagellin types and …


Eng 300: The Efficacy Of Bacteriophage & Lysin Antimicrobials In Industrial & Commercial Settings, Bella Norman Jan 2022

Eng 300: The Efficacy Of Bacteriophage & Lysin Antimicrobials In Industrial & Commercial Settings, Bella Norman

English 100-200-300 Conference

No abstract provided.


Identification Of A Rickettsial Endosymbiont In A Soft Tick Ornithodoros Turicata Americanus, Lichao Liu, Daniel E. Sonenshine, Hameeda Sultana, Girish Neelakanta Jan 2022

Identification Of A Rickettsial Endosymbiont In A Soft Tick Ornithodoros Turicata Americanus, Lichao Liu, Daniel E. Sonenshine, Hameeda Sultana, Girish Neelakanta

Biological Sciences Faculty Publications

Bacterial endosymbionts are abundantly found in both hard and soft ticks. Occidentia massiliensis, a rickettsial endosymbiont, was first identified in the soft tick Ornithodoros sonrai collected from Senegal and later was identified in a hard tick Africaniella transversale. In this study, we noted the presence of Occidentia species, designated as Occidentia-like species, in a soft tick O. turicata americanus. Sequencing and phylogenetic analyses of the two genetic markers, 16S rRNA and groEL confirmed the presence of Occidentia-like species in O. turicata americanus ticks. The Occidentia-like species was noted to be present in all developmental stages …


Tick Transmission Of Borrelia Burgdorferi To The Murine Host Is Not Influenced By Environmentally Acquired Midgut Microbiota, Sukanya Narasimhan, Nallakkandi Rajeevan, Morven Graham, Ming-Jie Wu, Kathleen Deponte, Solenne Marion, Orlanne Masson, Anya J. O'Neal, Daniel E. Sonenshine, Erol Fikrig Jan 2022

Tick Transmission Of Borrelia Burgdorferi To The Murine Host Is Not Influenced By Environmentally Acquired Midgut Microbiota, Sukanya Narasimhan, Nallakkandi Rajeevan, Morven Graham, Ming-Jie Wu, Kathleen Deponte, Solenne Marion, Orlanne Masson, Anya J. O'Neal, Daniel E. Sonenshine, Erol Fikrig

Biological Sciences Faculty Publications

Background

Ixodes scapularis is the predominant tick vector of Borrelia burgdorferi, the agent of Lyme disease, in the USA. Molecular interactions between the tick and B. burgdorferi orchestrate the migration of spirochetes from the midgut to the salivary glands—critical steps that precede transmission to the vertebrate host. Over the last decade, research efforts have invoked a potential role for the tick microbiome in modulating tick-pathogen interactions.

Results

Using multiple strategies to perturb the microbiome composition of B. burgdorferi-infected nymphal ticks, we observe that changes in the microbiome composition do not significantly influence B. burgdorferi migration from the midgut, invasion of …