Microbiology Commons^™

Comparison Of Two Methods (Precipitation Manual And Fully Automated Enzymatic) For The Analysis Of Hdl And Ldl Cholesterol, Jawaid Jabbar, Imran Siddiqui, Qaiser Raza

Department of Pathology and Laboratory Medicine

Objective:
To compare accuracy and throughput time for the measurement of HDL and LDL cholesterol by manual precipitation and fully automated enzymatic methods.
Methods:
Fifty, serum samples collected over a 4 months period (February - May 2004) were analyzed for HDL and LDL cholesterol by two different methods i.e. precipitation manual and automatic enzymatic method in the section of chemical pathology, Department of Pathology and Microbiology, Aga Khan University Hospital, Karachi Pakistan.
Results:
The mean standard deviation for HDL Cholesterol by precipitation method and automated method were 43.12 +/- 8.97mg/dl and 43.86 +/- 10.34mg/dl respectively (p-value = 0.301). The …

Antibiotic Resistant And Coliform Bacteria In The Ohio River; 2002 To 2004, Lisa Marie Smith

Theses, Dissertations and Capstones

During 2002 and 2003 samples, collected every five miles along the Ohio River, were analyzed for total cultivable bacteria, ciprofloxacin resistant bacteria, erythromycin resistant bacteria, tetracycline resistant bacteria, and fecal coliforms. During 2004 samples were analyzed for total cultivable bacteria, ciprofloxacin resistant bacteria, sulfamethizole resistant bacteria, tetracycline resistant bacteria, Virginiamycin resistant bacteria, total coliforms, and Escherichia coli. The objectives of this study were to systematically collect data on fecal coliforms, E. coli, and antibiotic resistant bacteria in the Ohio River and its major tributaries; to determine if antibiotic resistance populations are correlated to each other or to coliforms; and …

A Group M Consensus Envelope Glycoprotein Induces Antibodies That Neutralize Subsets Of Subtype B And C Hiv-1 Primary Viruses, Hua-Xin Lin, Laura L. Sutherland, Shi-Mao Xia, Mary E. Brock, Richard M. Scearce, Stacie Vanleeuwen, S. Munir Alam, Mildred Mcadams, Eric A. Weaver, Zenaido T. Camacho, Ben-Jiang Ma, Yingying Li, Julie M. Decker, Gary J. Nabel, David C. Montefiori, Beatrice H. Hahn, Bette T. Korber, Feng Gao, Barton F. Haynes

Nebraska Center for Virology: Faculty Publications

HIV-1 subtype C is the most common HIV-1 group M subtype in Africa and many parts of Asia. However, to date HIV-1 vaccine candidate immunogens have not induced potent and broadly neutralizing antibodies against subtype C primary isolates. We have used a centralized gene strategy to address HIV-1 diversity, and generated a group M consensus envelope gene with shortened consensus variable loops (CON-S) for comparative studies with wildtype (WT) Env immunogens. Our results indicate that the consensus HIV-1 group M CON-S Env elicited cross-subtype neutralizing antibodies of similar or greater breadth and titer than the WT Envs tested, indicating the …

Transposon Disruption Of The Complex I Nadh Oxidoreductase Gene (Snod) In Staphylococcus Aureus Is Associated With Reduced Susceptibility To The Microbicidal Activity Of Thrombin-Induced Platelet Microbicidal Protein 1, Arnold S. Bayer, Peter Mcnamara, Michael R. Yeaman, Natalie Lucindo, Tiffanny Jones, Ambrose L. Cheung

Dartmouth Scholarship

The cationic molecule thrombin-induced platelet microbicidal protein 1 (tPMP-1) exerts potent activity against Staphylococcus aureus. We previously reported that a Tn551 S. aureus transposon mutant, ISP479R, and two bacteriophage back-transductants, TxA and TxB, exhibit reduced in vitro susceptibility to tPMP-1 (tPMP-1(r)) compared to the parental strain, ISP479C (V. Dhawan, M. R. Yeaman, A. L. Cheung, E. Kim, P. M. Sullam, and A. S. Bayer, Infect. Immun. 65:3293-3299, 1997). In the current study, the genetic basis for tPMP-1(r) in these mutants was identified. GenBank homology searches using sequence corresponding to chromosomal DNA flanking Tn551 mutant strains showed that the fourth gene …

Comparison Of Microbial Water Quality Parameters Of Four Geographically Similar Creeks In Northeast Tennessee, Kimberlee K. Hall, L. K. Gallagher, Brian G. Evanshen, Kurt J. Maier, Phillip R. Scheuerman

ETSU Faculty Works

Four creeks within the Watauga River watershed in Northeast Tennessee are routinely monitored for water quality assessments. To identify sources and monitor remediation, Sinking Creek, Cash Hollow Creek, Buffalo Creek and Boones Creek are monitored for chemical and microbial parameters. These parameters include phosphates, nitrates, BOD and fecal coliforms. Sinking Creek is a tributary of the Watauga River with 10 miles of impaired water. Cash Hollow Creek enters the Watauga River at river mile 11.4 with 3.4 miles of impaired water. Boones Creek contains 18.6 impaired miles while the status of water quality in Buffalo Creek is not yet determined. …

Molecular Epidemiology Of Antibiotic Resistant Salmonella Enterica Strains From Different Animal And Human Sources In Ireland, David George Lee

Theses

In this study, 176 isolates of Salmonella were collected from different laboratories in Ireland. All isolates were confirmed to be of the genus Salmonella by performing bacteriological and biochemical tests. Briefly, all isolates were cultured onto XLD agar after which pure cultures were verified and stocked at this institute. Definitive identification was carried out using the API 20-E system and a separate urease test was also performed on all isolates. After confirmation of the genus, all isolates were prepared for antibiotic susceptibility testing and r-types were determined using sixteen antibiotics. Depending on the antibiotic resistance profiles, isolates were selected for …

Comparison Study Of Sediment Microbial Enzyme Activities To Biochemical Oxygen Demand, Nitrate Concentration, Phosphate Concentration In The Sediments Of A Fecally-Contaminated Stream In Northeast Tennessee Relative To Season And Land Use, Brian G. Evanshen, Kurt J. Maier, Phillip R. Scheuerman

ETSU Faculty Works

Microbial metabolism reacts quickly to environmental conditions. These reactions are dependent on the need for nutrients and respiration and can be measured using an assay of individual microbial enzyme activities (MEA’s). In this study, we measured MEA’s in the sediments of a stream in northeast Tennessee that had an approved fecal coliform Total Maximum Daily Load (TMDL). These values were compared to biochemical oxygen demand (BOD), phosphate concentration and nitrate concentration in the water column of this stream. Comparisons were grouped by season and land use. Stream sediments and water were collected monthly for one year and then quarterly for …

Screening For Cystic Fibrosis: The Importance Of Using The Correct Tools, Uzma Shah, Tariq Moatter

Department of Pathology and Laboratory Medicine

Background: Cystic Fibrosis (CF) is a potentially lethal genetic disorder. The most frequent mutation worldwide in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene is designated as the Delta F508 mutation. This mutation was found in only 33% of Pakistani patients studied. Since the common Pakistani mutations remain to be identified, appropriate screening tools are required to identify disease. Sweat chloride determinations remain the gold standard for diagnosing CF. This study was done to emphasize the importance of using the correct tests.
Methods: The study was conducted at the Aga Khan University Hospital. The CFTR delta F508 mutation was tested …

M. Leprae Inhibits Apoptosis In Thp-1 Cells By Downregulation Of Bad And Bak And Upregulation Of Mcl-1 Gene Expression, Zahra Hasan, Mussarat Ashraf, Ali Tayyebi, Rabia Hussain

Department of Pathology and Laboratory Medicine

Background: Virulent Mycobacterium leprae interfere with host defense mechanisms such as cytokine activation and apoptosis. The mitochondrial pathway of apoptosis is regulated by the Bcl-2 family of proteins. Expression of Fas ligand and apoptotic proteins is found in leprosy lesions and M. leprae has been shown to activate pro-apoptotic Bcl-2 genes, Bak and Bax. However, the mechanism by which M. leprae modulates apoptosis is as yet unclear. We investigated expression of apoptotic genes in THP-1 monocytes in response to infection by M. leprae and non-pathogenic M. bovis BCG.
Results: M. leprae did not induce apoptosis in THP-1 cells, while BCG …

Design Clues From Functional Constraints And Broadly Neutralizing Antibodies, Tongqing Zhou, Ling Xu, Barna Dey, Ann J. Hessell, Shahzad Majeed, Donald Van Ryk, Shi-Hua Xiang, Xinzhen Yang, Mei-Yun Zhang, Michael B. Zwick, James Arthos, Dennis R. Burton, Dimiter S. Dimitrov, Joseph Sodroski, Richard Wyatt, Gary J. Nabel, Peter D. Kwong

Nebraska Center for Virology: Faculty Publications

No abstract provided.

Cross-Subtype T-Cell Immune Responses Induced By A Human Immunodeficiency Virus Type 1 Group M Consensus Env Immunogen, Eric A. Weaver, Zenaido T. Camacho, Fatiha Moukdar, Hua-Xin Liao, Ben-Jiang Ma, Mark Muldoon, James Theiler, Gary J. Nabel, Norman L. Letvin, Bette T. Korber, Beatrice H. Hahn, Barton F. Haynes, Feng Gao, Zhongjing Lu

Nebraska Center for Virology: Faculty Publications

The genetic diversity among globally circulating human immunodeficiency virus type 1 (HIV-1) strains is a serious challenge for HIV-1 vaccine design. We have generated a synthetic group M consensus env gene (CON6) for induction of cross-subtype immune responses and report here a comparative study of T-cell responses to this and natural strain env immunogens in a murine model. Three different strains of mice were immunized with CON6 as well as subtype A, B, or C env immunogens, using a DNA prime-recombinant vaccinia virus boost strategy. T-cell epitopes were mapped by gamma interferon enzyme-linked immunospot analysis using five overlapping Env peptide …

The Analysis And Characterisation Of Rotavirus And Norovirus Circulating In The South Of Ireland, Norma Reidy

Theses

On average more than 3,000 cases of rotavirus diarrhea are detected annually amongst Irish children less than 3 years of age. Rotavirus disease occurs mainly during the winter months, with peak infections detected from February to April. The symptoms of disease are diarrhea and dehydration, with 80% of patients requiring hospitalisation, The mean duration of hospitalisation is 3-4 days, with an average cost per day of €409. Eighteen percent of infections were detected in infants less than 6 months of age, suggesting inadequate maternal derived protection from existing strains, or the existence of novel strains in Ireland with little or …

Validity Of Frozen Section In The Diagnosis Of Breast Lumps: 5 Years Experience At The Aga Khan University Hospital., Naila Kayani, Nuzhat Sultana

Department of Pathology and Laboratory Medicine

Abstract

Objective: To determine the accuracy of frozen section in the diagnosis of breast lump. Methods: Frozen section diagnosis given in consecutive breast biopsies performed in 5 years in our laboratory was evaluated against the final pathology report of permanent sections. Results: The Aga Khan University Hospital Lab receives more than 400 cases per year for frozen section. Three hundred and nineteen consecutive frozen sections of breast lumps examined from 1999-2003 were considered for analysis. Age of patients ranged between 22 and 90 years (mean age 49 years). In 316 cases (99%) there was no difference between the frozen section …

Rhamnolipids Modulate Swarming Motility Patterns Of Pseudomonas Aeruginosa, Nicky C. Caiazza, Robert M. Q. Shanks, G. A. O'Toole

Dartmouth Scholarship

Pseudomonas aeruginosa is capable of twitching, swimming, and swarming motility. The latter form of translocation occurs on semisolid surfaces, requires functional flagella and biosurfactant production, and results in complex motility patterns. From the point of inoculation, bacteria migrate as defined groups, referred to as tendrils, moving in a coordinated manner capable of sensing and responding to other groups of cells. We were able to show that P. aeruginosa produces extracellular factors capable of modulating tendril movement, and genetic analysis revealed that modulation of these movements was dependent on rhamnolipid biosynthesis. An rhlB mutant (deficient in mono- and dirhamnolipid production) and …

Heterotopic Glial Tissue In Tonsil: A Case Report, Nausheen Yaqoob, Zubair Ahmed, Akhtar Husain

Department of Pathology and Laboratory Medicine

We describe a six month old boy with a mass in the left tonsil. It was present since birth and was enlarging progressively. It was completely excised. Histopathology showed a choristoma of neural origin composed of glial cells--astrocytes in a fibrillary background, and a choroid plexus. Immunohistochemistry confirmed the findings.

Metanephric Adenoma: A Rare Benign Renal Tumour, Nausheen Yaqoob, Jai Pal Paryani, Naila Kayani, Mohammad Zafar Rafique, Raziuddin Biyabani

Department of Pathology and Laboratory Medicine

Metanephric adenoma is a rare benign renal tumour. We are reporting one histologically proven such case in a 23 year old male from Afghanistan. He presented with severe right flank pain since 3 weeks. Nephrectomy was done and histopathology was consistent with the diagnosis of metanephric adenoma. This novel renal mass has been reported to have benign clinical course despite its symptomatic presentation and large tumour size. There is no distinguishing radiological feature with can differentiate it from malignant tumours. So far, a uniformly benign clinical course has been associated with Metanephric adenoma, but given its relatively recent identification and …

Lymphoepithelioma-Like Carcinoma Of Urinary Bladder: (Lelca), Nausheen Yaqoob, Naila Kayani, Jaipal Piryani, Mohammad Nasir Sulaiman, Sheema H. Hasan

Department of Pathology and Laboratory Medicine

Lymphoepithelioma-like carcinoma of the bladder (LELCA) is an uncommon neoplasm of the urinary bladder and up till now only 49 cases have been reported in the English literature. It is imperative to distinguish between lymphoepithelioma-like carcinoma and malignant lymphoma as primary bladder lymphoma is extremely rare. We report a case of a 55 year old lady who presented with the complaint of burning micturition and gross hematuria for the past 5 months. There were no other known comorbids. Pelvic ultrasound was normal. Cystoscopy showed a 4x4 cm sessile mass in the bladder. Histopathological examination was consistent with the diagnosis of …

Sara Positively Controls Bap-Dependent Biofilm Formation In Staphylococcus Aureus, María P. Trotonda, Adhar C. Manna, Ambrose L. Cheung, Iñigo Lasa, José R. Penadés

Dartmouth Scholarship

The biofilm-associated protein Bap is a staphylococcal surface protein involved in biofilm formation. We investigated the influence of the global regulatory locus sarA on bap expression and Bap-dependent biofilm formation in three unrelated Staphylococcus aureus strains. The results showed that Bap-dependent biofilm formation was diminished in the sarA mutants by an agr-independent mechanism. Complementation studies using a sarA clone confirmed that the defect in biofilm formation was due to the sarA mutation. As expected, the diminished capacity to form biofilms in the sarA mutants correlated with the decreased presence of Bap in the bacterial surface. Using transcriptional fusion and …

Mannose Binding Lectin Genotypes Influence Recovery From Hepatitis B Virus Infection, Chloe L. Thio, Timothy L. Mosbruger, Jacquie Astemborski, Spencer Greer, Gregory D. Kirk, Stephen J. O'Brien, David L. Thomas

Biology Faculty Articles

Mannose binding lectin (MBL) is a central component of the innate immune response and thus may be important for determining hepatitis B virus (HBV) persistence. Since single-nucleotide polymorphisms (SNPs) in the gene encoding MBL (mbl2) alter the level of functional MBL, we hypothesized that mbl2 genotypes are a determinant of HBV persistence or recovery from viral infection. We tested this hypothesis by using a nested case control design with 189 persons with HBV persistence matched to 338 individuals who had naturally recovered from HBV infection. We determined genotypes of two promoter and three exon 1 SNPs in mbl2 …

To Compare The Total Cholesterol And Hdl-Cholesterol Before And After Ultra-Centrifugation In Lipemic Samples, Jawaid Jabbar, Imran Siddiqui, Syed Qaiser Raza, Ayaz Baig

Department of Pathology and Laboratory Medicine

Objective: It is an everyday routine in laboratories to encounter interference in the analysis of lipids. These likely interferences (hemolysis, icterus and lipemia) are countered by asking physicians and patients to send fresh and properly collected samples. At the Aga Khan University (AKU) Laboratory, we receive 2-3 lipemic/turbid samples per day. Previously it was our departmental policy to advise these patients to go for lipoprotein electrophoresis, which though accurate was time consuming and not cost effective. We therefore studied ultra centrifugation/airfuge as an alternate method to clear lipid interference and provide accurate, reliable and cost effective results.
Methods: Daily 2-3 …

Requirements For Vibrio Cholerae Hapr Binding And Transcriptional Repression At The Hapr Promoter Are Distinct From Those At The Apha Promoter, Wei Lin, Gabriela Kovacikova, Karen Skorupski

Dartmouth Scholarship

Virulence gene expression in certain strains of Vibrio cholerae is regulated in response to cell density by a quorum-sensing cascade that influences the levels of the LuxR homolog HapR through small regulatory RNAs that control the stability of its message. At high cell density, HapR represses the expression of the gene encoding the virulence gene activator AphA by binding to a site between −85 and −58 in the aphA promoter. We show here that a second binding site for HapR lies within the hapR promoter from which it functions to repress its own transcription. This site, as determined by gel …

Ductal Carcinoma In Situ (Dcis) In Karachi, Naila Kayani, Yasmin Bhurgri

Department of Pathology and Laboratory Medicine

Objective:
To study the frequency of ductal carcinoma in situ (DCIS) in a large pathology series. DCIS is a proliferation of non-invasive, malignant epithelial cells within the ductolobular system of the breast. It is a heterogeneous entity with several morphologic variants that differ in gross appearance, growth pattern, cytologic features, mammography, and malignant potential.
Methods:
The data of The Aga Khan University' Pathology Department, diagnosed on the basis of histopathology, during a 6-year period (1st January 1998 to 31st December 2003) was reviewed, all cases of DCIS studied, and data was analyzed with the help of analytical software SPSS.
Results: …

Trefoil Factor 2 (Tff2) Deficiency In Murine Digestive Tract Influences The Immune System, M. Baus- Loncar, J. Schmid, El-Nasir Lalani, I. Rosewell, R. A. Goodlad, H. G.W. Stamp, N. Blin, T. Kayademir

Department of Pathology and Laboratory Medicine

Background & Aims:

The gastrointestinal trefoil factor family (TFF1, TFF2, TFF3) peptides are considered to play an important role in maintaining the integrity of the mucosa. The physiological role of TFF2 in the protection of the GI tract was investigated in TFF2 deficiency.

Methods:

TFF2-/- mice were generated and differential expression of various genes was assessed by using a mouse expression microarray, quantitative real time PCR, Northern blots or immunohistochemistry.

Results:

On an mRNA level we found 128 differentially expressed genes. We observed modulation of a number of crucial genes involved in innate and adaptive immunity in the TFF2-/- mice. …

Insertional Polymorphisms Of Endogenous Feline Leukemia Viruses, Alfred L. Roca, William G. Nash, Joan C. Menninger, William J. Murphy, Stephen J. O'Brien

Biology Faculty Articles

The number, chromosomal distribution, and insertional polymorphisms of endogenous feline leukemia viruses (enFeLVs) were determined in four domestic cats (Burmese, Egyptian Mau, Persian, and nonbreed) using fluorescent in situ hybridization and radiation hybrid mapping. Twenty-nine distinct enFeLV loci were detected across 12 of the 18 autosomes. Each cat carried enFeLV at only 9 to 16 of the loci, and many loci were heterozygous for presence of the provirus. Thus, an average of 19 autosomal copies of enFeLV were present per cat diploid genome. Only five of the autosomal enFeLV sites were present in all four cats, and at only one …

Sara Is An Essential Positive Regulator Of Staphylococcus Epidermidis Biofilm Development, Maria A. Tormo, Miguel Marti, Jaione Valle, Adhar C. Manna

Dartmouth Scholarship

Staphylococcus epidermidis biofilm formation is associated with the production of the polysaccharide intercellular adhesin (PIA)--poly-N-acetylglucosamine polysaccharide (PNAG) by the products of the icaADBC operon. Recent evidence indicates that SarA, a central regulatory element that controls the production of Staphylococcus aureus virulence factors, is essential for the synthesis of PIA/PNAG and the ensuing biofilm development in this species. Based on the presence of a sarA homolog, we hypothesized that SarA could also be involved in the regulation of the biofilm formation process in S. epidermidis. To investigate this, we constructed nonpolar sarA deletions in two genetically unrelated S. epidermidis clinical strains, …

Identification Of A Tcpc-Tcpq Outer Membrane Complex Involved In The Biogenesis Of The Toxin-Coregulated Pilus Of Vibrio Cholerae, Niranjan Bose, Ronald K. Taylor

Dartmouth Scholarship

The toxin-coregulated pilus (TCP) of Vibrio cholerae and the soluble TcpF protein that is secreted via the TCP biogenesis apparatus are essential for intestinal colonization. The TCP biogenesis apparatus is composed of at least nine proteins but is largely uncharacterized. TcpC is an outer membrane lipoprotein required for TCP biogenesis that is a member of the secretin protein superfamily. In the present study, analysis of TcpC in a series of strains deficient in each of the TCP biogenesis proteins revealed that TcpC was absent specifically in a tcpQ mutant. TcpQ is a predicted periplasmic protein required for TCP biogenesis. Fractionation …

Mechanisms Of Cell Death Initiated In Herpes Simplex Virus Thymidine Kinase Expressing Colon Tumor Cells Treated With Ganciclovir And Ucn-01, Christina Elizabeth Ahn

Theses and Dissertations in Biomedical Sciences

Metastatic colon carcinoma is the second leading cause of death from malignancy in the United States, and development of more effective treatments is essential. Heterologous expression of Herpes Simplex Virus Thymidine Kinase (HSVtk) in combination with the prodrug, ganciclovir (GCV), has shown great promise for the genetic therapy of many cancers, but most patients have had only a partial or minimal response to the therapy. After screening a panel of two drug combinations, our laboratory has shown that the combination of GCV and the protein kinase inhibitor UCN-01 (7-hydroxystaurosporine) enhances tumor cell death more effectively than either drug alone. However …

Psychomotor Skills For The Undergraduate Medical Curriculum In A Developing Country--Pakistan, Rashida Ahmed, Zoon Naqvi, Ineke Wolfhagen

Department of Pathology and Laboratory Medicine

Objective: To identify essential psychomotor skills for all the medical graduates of an undergraduate programme in Pakistan.
Materials and Methods: Twenty-five physicians practising in a tertiary care centre and ninety primary care physicians used a Likert's scale, ranging from "very essential" to"not required at all", to mark 99 psychomotor skills in the undergraduate medical curriculum in Pakistan.
Results: Overall the opinions of both the groups about the essential skills matched except for a few areas.
Conclusion: This study provides baseline data about psychomotor skills that a medical graduate in developing countries should be able to perform. Further studies will be …

Ovarian Primary Neuroendocrine Carcinoma Of Non-Small Cell Type: Report Of An Extremely Rare Neoplasm, Zubair Ahmed, Kanwal Aftab, Naila Kayani

Department of Pathology and Laboratory Medicine

Paraffin block sections of a uterus and ovarian mass from a 31 year old female were sent for second opinion to the Pathology Laboratory of Aga Khan University. Histologic examination and immunohistochemical features gave a diagnosis of primary neuroendocrine carcinoma of non-small cell type admixed with benign mucinous cystadenoma. This is a rare tumour with only eight being reported in literature.

A Three-Component Regulatory System Regulates Biofilm Maturation And Type Iii Secretion In Pseudomonas Aeruginosa, Sherry L. Kuchma, John P. Connolly, George A. O'Toole

Dartmouth Scholarship

Biofilms are structured communities found associated with a wide range of surfaces. Here we report the identification of a three-component regulatory system required for biofilm maturation by Pseudomonas aeruginosa strain PA14. A transposon mutation that altered biofilm formation in a 96-well dish assay originally defined this locus, which is comprised of genes for a putative sensor histidine kinase and two response regulators and has been designated sadARS. Nonpolar mutations in any of the sadARS genes result in biofilms with an altered mature structure but do not confer defects in growth or early biofilm formation, swimming, or twitching motility. After …