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Full-Text Articles in Microbiology

Genotyping And Drug Resistance Patterns Of M. Tuberculosis Strains In Pakistan., Mahnaz Tanveer, Zahra Hasan, Amna R Siddiqui, Asho Ali, Akbar Kanji, Solomon Ghebremicheal, Rumina Hasan Dec 2008

Genotyping And Drug Resistance Patterns Of M. Tuberculosis Strains In Pakistan., Mahnaz Tanveer, Zahra Hasan, Amna R Siddiqui, Asho Ali, Akbar Kanji, Solomon Ghebremicheal, Rumina Hasan

Department of Pathology and Laboratory Medicine

Background:The incidence of tuberculosis in Pakistan is 181/100,000 population. However, information about transmission and geographical prevalence of Mycobacterium tuberculosis strains and their evolutionary genetics as well as drug resistance remains limited. Our objective was to determine the clonal composition, evolutionary genetics and drug resistance of M. tuberculosis isolates from different regions of the country.

Methods:

M. tuberculosis strains isolated (2003-2005) from specimens submitted to the laboratory through collection units nationwide were included. Drug susceptibility was performed and strains were spoligotyped.

Results:

Of 926 M. tuberculosis strains studied, 721(78%) were grouped into 59 "shared types", while 205 (22%) were identified …


Effects Of Shielding Adenoviral Vectors With Polyethylene Glycol On Vector-Specific And Vaccine-Mediated Immune Responses, Eric A. Weaver, Michael A. Barry Dec 2008

Effects Of Shielding Adenoviral Vectors With Polyethylene Glycol On Vector-Specific And Vaccine-Mediated Immune Responses, Eric A. Weaver, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Many individuals have been previously exposed to human adenovirus serotype 5 (Ad5). This prior immunity has long been known to hinder its use for gene therapy and as a gene-based vaccine. Given these immunogenicity problems, we have tested whether polyethylene glycol (PEG) can blunt immune effects against Ad5 during systemic and mucosal vaccination. Ad5 vectors were covalently modified with 5-, 20-, and 35-kDa linear PEG polymers and evaluated for their ability to produce immune responses against transgene antigen products and the vector itself. We show that shielding Ad5 with different-sized PEGs generally reduces transduction and primary antibody responses by the …


Prevalence And Factors Associated With Intestinal Parasitic Infection Among Children In An Urban Slum Of Karachi., Vikram Mehraj, Juanita Hatcher, Saeed Akhtar, Ghazala Rafique, Mohammad Asim Beg Nov 2008

Prevalence And Factors Associated With Intestinal Parasitic Infection Among Children In An Urban Slum Of Karachi., Vikram Mehraj, Juanita Hatcher, Saeed Akhtar, Ghazala Rafique, Mohammad Asim Beg

Department of Pathology and Laboratory Medicine

Background:Intestinal parasitic infections are endemic worldwide and have been described as constituting the greatest single worldwide cause of illness and disease. Poverty, illiteracy, poor hygiene, lack of access to potable water and hot and humid tropical climate are the factors associated with intestinal parasitic infections. The study aimed to estimate prevalence and identify factors associated with intestinal parasitic infections among 1 to 5 years old children residing in an urban slum of Karachi Pakistan. Methods And Principal
Findings:A cross sectional survey was conducted from February to June 2006 in Ghosia Colony Gulshan Town Karachi, Pakistan. A simple random …


Global Analysis Of Gene Expression Changes During Retinoic Acid-Induced Growth Arrest And Differentiation Of Melanoma: Comparison To Differentially Expressed Genes In Melanocytes Vs Melanoma, Mary H. Estler, Goran Boskovic, James Denvir, Sarah Miles, Donald A. Primerano, Richard M. Niles Oct 2008

Global Analysis Of Gene Expression Changes During Retinoic Acid-Induced Growth Arrest And Differentiation Of Melanoma: Comparison To Differentially Expressed Genes In Melanocytes Vs Melanoma, Mary H. Estler, Goran Boskovic, James Denvir, Sarah Miles, Donald A. Primerano, Richard M. Niles

Biochemistry and Microbiology

BACKGROUND: The incidence of malignant melanoma has significantly increased over the last decade. Some of these malignancies are susceptible to the growth inhibitory and pro-differentiating effects of all-trans-retinoic acid (RA). The molecular changes responsible for the biological activity of RA in melanoma are not well understood.

RESULTS: In an analysis of sequential global gene expression changes during a 4-48 h RA treatment of B16 mouse melanoma cells, we found that RA increased the expression of 757 genes and decreased the expression of 737 genes. We also compared the gene expression profile (no RA treatment) between non-malignant melan-a mouse melanocytes and …


Time Trends In The Incidence Of Cancer Cervix In Karachi South, 1995-2002, Yasmin Bhurgri, Shahid Pervez, Naila Kayani, Muneeza Afif, Imran Tahir, Kauser Nazir, Ahmed Usman, Naveen Faridi, Hadi Bhurgri, Jawaid Malik, Imtiaz Bashir, Asif Bhurgri, Rashida Ahmed, Sheema H Hasan, Mohammad Khurshid, S. M. H. Zaidi Jul 2008

Time Trends In The Incidence Of Cancer Cervix In Karachi South, 1995-2002, Yasmin Bhurgri, Shahid Pervez, Naila Kayani, Muneeza Afif, Imran Tahir, Kauser Nazir, Ahmed Usman, Naveen Faridi, Hadi Bhurgri, Jawaid Malik, Imtiaz Bashir, Asif Bhurgri, Rashida Ahmed, Sheema H Hasan, Mohammad Khurshid, S. M. H. Zaidi

Department of Pathology and Laboratory Medicine

Introduction:The objective of the study was to determine the trends of cancer cervix in Karachi South during an eight (1995-2002) year period. Methododology: Cancer cervix cases recorded at Karachi Cancer Registry during 1st January 1995 to 31st December 2002 were analyzed. Trends were studied by analyzing the age standardized incidence rates (ASR)s in 2 time periods, 1995-97 and 1998-2002.

Results:

Cancer cervix ranked sixth in the 1995-97 period the age standardized incidence rate (ASR) world and crude incidence rate (CIR) per 100,000 were 6.81 and 3.22. It reached the fifth ranking in the 1998-2002 period with an ASR and …


Emergence Of Carbapenem Resistant Gram Negative And Vancomycin Resistant Gram Positive Organisms In Bacteremic Isolates Of Febrile Neutropenic Patients: A Descriptive Study., Seema Irfan, Faiza Idrees, Vikram Mehraj, Faizah Habib, Salman Adil, Rumina Hasan Jun 2008

Emergence Of Carbapenem Resistant Gram Negative And Vancomycin Resistant Gram Positive Organisms In Bacteremic Isolates Of Febrile Neutropenic Patients: A Descriptive Study., Seema Irfan, Faiza Idrees, Vikram Mehraj, Faizah Habib, Salman Adil, Rumina Hasan

Department of Pathology and Laboratory Medicine

Background:This study was conducted to evaluate drug resistance amongst bacteremic isolates of febrile neutropenic Patients with particular emphasis on emergence of carbapenem resistant Gram negative bacteria and vancomycin resistant Enterococcus species.

Methods:

A descriptive study was performed by reviewing the blood culture reports from febrile neutropenic Patients during the two study periods i.e., 1999-00 and 2001-06. Blood cultures were performed using BACTEC 9240 automated system. Isolates were identified and antibiotic sensitivities were done using standard microbiological procedures.

Results:

Seven twenty six febrile neutropenic Patients were admitted during the study period. A total of 5840 blood cultures were received, off …


Mechanisms Of T Helper Cell Modulation In A Simulated Space Radiation Environment, Asma Rizvi Jun 2008

Mechanisms Of T Helper Cell Modulation In A Simulated Space Radiation Environment, Asma Rizvi

Loma Linda University Electronic Theses, Dissertations & Projects

Exposure to solar particle events (SPEs) poses the most serious threat to astronaut health. Due to this radiation environment, exploration of the solar system beyond Earth’s orbit entails many risks for the crew on these deep space missions. Depression or dysfunction of the immune system is a major concern due to its high radio-sensitivity; potential consequences include overwhelming infection, development of cancer, fibrosis, and poor wound healing. Astronauts are also exposed to low dose/low dose rate (LDR) radiation. A three month stay at the international space station exposes them to ~ 0.05 Gy of radiation.

C57BL/6 mice received LDR gamma-radiation …


Precipitating Factors Of Hepatic Encephalopathy In Patients With Chronic Liver Disease At Civil Hospital Karachi, Dileep K Rohra, Jaipal, Ameer A Khowaja, Khalid Mahmood, Kanya Lal Ahuja Feb 2008

Precipitating Factors Of Hepatic Encephalopathy In Patients With Chronic Liver Disease At Civil Hospital Karachi, Dileep K Rohra, Jaipal, Ameer A Khowaja, Khalid Mahmood, Kanya Lal Ahuja

Department of Biological & Biomedical Sciences

No abstract provided.


Diagnostic Tool For Glanzmann's Thrombasthenia Clinicopathologic Spectrum, Natasha Bahadur Ali, Bushra Moiz, Mohammad Usman Shaikh, Salman Adil, Bushra Rizvi, Yasmeen Rahman Feb 2008

Diagnostic Tool For Glanzmann's Thrombasthenia Clinicopathologic Spectrum, Natasha Bahadur Ali, Bushra Moiz, Mohammad Usman Shaikh, Salman Adil, Bushra Rizvi, Yasmeen Rahman

Department of Pathology and Laboratory Medicine

Objective: To platelet aggregometry and describe the clinical spectrum of Glanzmann's thrombasthenia diagnosed by platelet aggregometry.
Study design: A case-series.
Place and duration of study: This study was carried out at the clinical laboratories at the Aga Khan University Hospital, Karachi from January 2003 to January 2006.
Patients and methods: All patients irrespective of age and gender presenting with bleeding symptoms and having normal platelet count were evaluated. Demographic details, relevant clinical history along with results of complete blood count, bleeding time and platelet aggregation studies were retrieved through computerized data base and evaluated for the diagnosis of Glanzmann's thrombasthenia. …


Role Of Transient Receptor Potential Canonical-6 (Trpc6) Channel In Metastasis Of Glioblastoma Multiforme, Rajarajeshwari Venkataraman Jan 2008

Role Of Transient Receptor Potential Canonical-6 (Trpc6) Channel In Metastasis Of Glioblastoma Multiforme, Rajarajeshwari Venkataraman

Electronic Theses and Dissertations

Glioblastoma multiforme (GBM) is one of the extremely fatal brain tumors. The main reason that makes it so lethal is its capability to invade and spread to other parts of CNS producing secondary tumors. Among other factors hypoxia, reduced oxygen availability, is linked to higher metastatic potential of cancers. Hypoxia causes numerous changes in genome and proteome of the cell. These changes help a normal cell to adapt to nutritional deficiency, but the same changes can increase the malignancy and metastasis in tumor cells. Extensive research by a number of curious scientists reveal that various pathways involving numerous proteins cross-talk …


Development Of An Immunofluorescence Assay Using Recombinant Proteins Expressed In Insect Cells To Screen And Confirm Presence Of Human Herpesvirus 8-Specific Antibodies, Veenu Minhas, Lynsey N. Crosby, Kay L. Crabtree, Saul Phiri, Tendai J. M'Soka, Chipepo Kankasa, William J. Harrington, Charles D. Mitchell, Charles Wood Jan 2008

Development Of An Immunofluorescence Assay Using Recombinant Proteins Expressed In Insect Cells To Screen And Confirm Presence Of Human Herpesvirus 8-Specific Antibodies, Veenu Minhas, Lynsey N. Crosby, Kay L. Crabtree, Saul Phiri, Tendai J. M'Soka, Chipepo Kankasa, William J. Harrington, Charles D. Mitchell, Charles Wood

Nebraska Center for Virology: Faculty Publications

Human herpesvirus 8 (HHV-8), or Kaposi’s sarcoma (KS)-associated herpesvirus, has been linked to all forms of KS. The results of most current serological assays for the detection of HHV-8-specific antibodies have low levels of concordance among themselves. To establish a sensitive and specific testing strategy that can be used to screen for HHV-8-specific antibodies, three HHV-8 proteins, ORF65, ORF73, and K8.1A, were expressed by using baculoviral vectors in insect cells and incorporated into a monoclonal antibodyenhanced immunofluorescence assay (mIFA) termed the Sf9 three-antigen mIFA. The results obtained by this mIFA were compared to those obtained by a standard mIFA with …


Small-Molecule Cd4 Mimics Interact With A Highly Conserved Pocket On Hiv-1 Gp120, Navid Madani, Arne Schön, Amy M. Princiotto, Judith M. Lalonde, Joel R. Cpurter, Takahiro Soeta, Danny Ng, Liping Wang, Evan T. Brower, Shi-Hua Xiang, Young Do Kwon, Chih-Chin Huang, Richard Wyatt, Peter D. Kwong, Ernesto Freire, Amos B. Smith Iii, Joseph Sodroski Jan 2008

Small-Molecule Cd4 Mimics Interact With A Highly Conserved Pocket On Hiv-1 Gp120, Navid Madani, Arne Schön, Amy M. Princiotto, Judith M. Lalonde, Joel R. Cpurter, Takahiro Soeta, Danny Ng, Liping Wang, Evan T. Brower, Shi-Hua Xiang, Young Do Kwon, Chih-Chin Huang, Richard Wyatt, Peter D. Kwong, Ernesto Freire, Amos B. Smith Iii, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

Human immunodeficiency virus (HIV-1) interaction with the primary receptor, CD4, induces conformational changes in the viral envelope glycoproteins that allow binding to the CCR5 second receptor and virus entry into the host cell. The small molecule NBD-556 mimics CD4 by binding the gp120 exterior envelope glycoprotein, moderately inhibiting virus entry into CD4-expressing target cells, and enhancing CCR5 binding and virus entry into CCR5-expressing cells lacking CD4. Studies of NBD-556 analogues and gp120 mutants suggest that: 1) NBD-556 binds within the Phe 43 cavity, a highly conserved, functionally important pocket formed as gp120 assumes the CD4- bound conformation; 2) the NBD-556 …


The Human Immunodeficiency Virus Type 1 Envelope Confers Higher Rates Of Replicative Fitness To Perinatally Transmitted Viruses Than To Nontransmitted Viruses, Xiaohong Kong, John T. West, Hong Zhang, Danielle M. Shea, Tendai J. M’Soka, Charles Wood Jan 2008

The Human Immunodeficiency Virus Type 1 Envelope Confers Higher Rates Of Replicative Fitness To Perinatally Transmitted Viruses Than To Nontransmitted Viruses, Xiaohong Kong, John T. West, Hong Zhang, Danielle M. Shea, Tendai J. M’Soka, Charles Wood

Nebraska Center for Virology: Faculty Publications

Selection of a minor viral genotype during perinatal transmission of human Immunodeficiency virus type 1

(HIV-1) has been observed, but there is a lack of information on the correlation of the restrictive transmission

with biological properties of the virus, such as replicative fitness. Recombinant viruses expressing the enhanced

green fluorescent protein or the Discosoma sp. red fluorescent (DsRed2) protein carrying the V1 to V5

regions of env from seven mother-infant pairs (MIPs) infected by subtype C HIV-1 were constructed, and

competition assays were carried out to compare the fitness between the transmitted and nontransmitted

viruses. Flow cytometry was used to …


Varying Efficiency Of Long-Term Replication Of Papillomaviruses In Saccharomyces Cerevisiae, Adam J. Rogers, Malte Loggen, Karen Lee, Peter C. Angeletti Jan 2008

Varying Efficiency Of Long-Term Replication Of Papillomaviruses In Saccharomyces Cerevisiae, Adam J. Rogers, Malte Loggen, Karen Lee, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

Human papillomaviruses (HPVs) replicate in mitotically active basal keratinocytes. Two virally encoded proteins, E1, a helicase, and E2, a transcription factor, are important players in replication and maintenance of HPV episomes. We previously showed that HPV16 could replicate stably in Saccharomyces cerevisiae [Angeletti, P.C., Kim, K., Fernandes, F.J., and Lambert, P.F. (2002)] and we identified cis-elements that mediate replication and maintenance [J. Virol. 76(7), 3350-3358.; Kim, K., Angeletti, P.C., Hassebroek, E.C., and Lambert, P.F. (2005)]. Here, we demonstrate that although multiple HPV genomes replicate stably in yeast, they do so with differing long-term efficiency; HPV6-Ura3 is replicated at the …


A Versatile Assay For The Identification Of Rna Silencing Suppressors Based On Complementation Of Viral Movement, Jason G. Powers, Tim L. Sit, Feng Qu, T. Jack Morris, Kook-Hyung Kim, Steven A. Lommel Jan 2008

A Versatile Assay For The Identification Of Rna Silencing Suppressors Based On Complementation Of Viral Movement, Jason G. Powers, Tim L. Sit, Feng Qu, T. Jack Morris, Kook-Hyung Kim, Steven A. Lommel

Nebraska Center for Virology: Faculty Publications

The cell-to-cell movement of Turnip crinkle virus (TCV) in Nicotiana benthamiana requires the presence of its coat protein (CP), a known suppressor of RNA silencing. RNA transcripts of a TCV construct containing a reporter gene (green fluorescent protein) (TCV-sGFP) in place of the CP open reading frame generated foci of three to five cells. TCV CP delivered in trans by Agrobacterium tumefaciens infiltration potentiated movement of TCV-sGFP and increased foci diameter, on average, by a factor of four. Deletion of the TCV movement proteins in TCV-sGFP (construct TCVΔ92-sGFP) abolished the movement complementation ability of TCV CP. Other known suppressors of …


Effects Of Shielding Adenoviral Vectors With Polyethylene Glycol On Vector-Specific And Vaccine-Mediated Immune Responses, Eric A. Weaver, Michael A. Barry Jan 2008

Effects Of Shielding Adenoviral Vectors With Polyethylene Glycol On Vector-Specific And Vaccine-Mediated Immune Responses, Eric A. Weaver, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Many individuals have been previously exposed to human adenovirus serotype 5 (Ad5). This prior immunity has long been known to hinder its use for gene therapy and as a gene-based vaccine. Given these immunogenicity problems, we have tested whether polyethylene glycol (PEG) can blunt immune effects against Ad5 during systemic and mucosal vaccination. Ad5 vectors were covalently modified with 5-, 20-, and 35-kDa linear PEG polymers and evaluated for their ability to produce immune responses against transgene antigen prod- ucts and the vector itself. We show that shielding Ad5 with different-sized PEGs generally reduces transduction and primary antibody responses by …


Detection And Molecular Epidemiological Analysis Of Acute Gastroenteritis Viruses In The South Of Ireland, Grainne Lennon Jan 2008

Detection And Molecular Epidemiological Analysis Of Acute Gastroenteritis Viruses In The South Of Ireland, Grainne Lennon

Theses

Rotavirus infections are considered to be the most common cause of severe gastroenteritis in children under the age of 5 years, and are responsible for up to 611,000 deaths annually, mainly in developing countries. From 1997 to 1999, 16 hospital laboratories in the Republic of Ireland reported to detection of 4,643 cases of rotaviral disease, while in 2004 and 2005 and increase of 1,600 and 2,251 rotavirus cases were reported. These rotavirus cases have a significant impact on the healthcare system with the minimum cost per case being €728.40. A large percentage of the infections were reported in neonates, suggesting …