151
|
Khan B, Khan AA, Khan MR. Pathogenic Variability Among Isolates of Meloidogyne javanica on Capsicum annum. J Nematol 2003; 35:430-432. [PMID: 19262775 PMCID: PMC2620690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
Meloidogyne javanica isolates were collected from nine districts of Uttar Pradesh. These isolates showed pathogenic variability when inoculated on the pepper cultivars California Wonder and Suryamukhi Green. Meloidogyne javanica that infected Suryamukhi Green but not California Wonder were designated as pepper race 1 and the populations that infected both the cultivars were designated pepper race 2. Race 1 was more frequent than race 2 in Almora, Pauri Garhwal, Basti, Gorakhpur, and Deoria, whereas race 2 was more frequent than race 1 in the Dehradun, Farrukhabad, Hardoi, and Sitapur districts. The overall frequencies were 70% and 30% for race 1 and race 2, respectively, in the study area.
Collapse
|
152
|
Khan AA, Abel PD, Chaudhary KS, Gulzar Z, Stamp GWH, Lalani EN. Inverse correlation between high level expression of cyclin E and proliferation index in transitional cell carcinoma of the bladder. Mol Pathol 2003; 56:353-61. [PMID: 14645699 PMCID: PMC1187355 DOI: 10.1136/mp.56.6.353] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/22/2003] [Indexed: 11/04/2022]
Abstract
BACKGROUND/AIMS Overexpression of the G1 cyclins, D1 and E, and/or downregulation of p27(Kip1) allow uncontrolled tumour cell proliferation. This study investigated the relation between these three cell cycle proteins and tumour proliferation in bladder cancer. METHOD Nuclear expression of cyclin D1, cyclin E, and p27(Kip1) was determined immunohistochemically in 52 primary transitional cell carcinomas, and the Ki-67 proliferation marker was also assessed. For each protein, the percentage of positive tumour cell nuclei was determined and analysed as a continuous variable. RESULTS Advancing tumour grade and pathological stage were accompanied by increasing proliferation indices, but decreasing p27(Kip1) and cyclin D1 expression, with no significant change in cyclin E expression. Overall, cyclin D1 and E expression did not correlate with proliferation. However, in cyclin D1 overexpressing tumours (> or = 5% nuclei positive), the level of cyclin D1 expression positively correlated with proliferation. The correlation between cyclin E expression and proliferation changed from positive to negative with increasing levels of cyclin E expression, accompanied by a coordinate increase in p27(Kip1) expression. Overall, there was an inverse association between p27(Kip1) expression and proliferation. However, a subset of tumours displayed high proliferation indices despite high p27(Kip1) expression. The G1 cyclin index (sum of the level of expression of cyclins D1 and E) correlated positively with proliferation in superficial but not muscle invasive tumours. This correlation was stronger when the G1 cyclin index was adjusted for p27(Kip1) expression. CONCLUSION These findings support a role for these proteins in the proliferation, differentiation, and progression of bladder transitional cell carcinomas.
Collapse
|
153
|
Rabbani MA, Khan AA, Ali SS, Ahmad B, Baig SM, Khan MA, Wasay M. Spectrum of complications and mortality of bacterial meningitis: an experience from a developing country. J PAK MED ASSOC 2003; 53:580-3. [PMID: 14765936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
OBJECTIVE The aim of this study was to obtain data on predisposing factors, causative organisms and their associated mortality and complications related to acute bacterial meningitis. METHODS The chart review of all patients in whom acute bacterial meningitis was diagnosed at The Aga Khan University Hospital from January 1995 through December 2001. RESULTS One hundred ninety-four patients were included in study. There were 146 males and 48 females. The mean age of our study population was 41 +/- 12.3 years. One hundred and ninety (97.9%) patients had community-acquired meningitis; only 4 (2.0%) patients developed meningitis nosocomially. The two most common predisposing factors were diabetes mellitus (13.9%) and otitis media (7.7%) among all 194 patients. A significant proportion of patients with complications had diabetes mellitus (24.6%, p < 0.001). CSF and blood cultures were positive in 53 (27.3%) and 42 (21.6%) patients respectively; there was no statistical difference found. The most common organisms isolated were Streptococcus pneumoniae in 35 (36.8%) patients followed by Neisseria meningitides in 30 (31.5%) patients. Approximately 68% of positive cultures yielded S. pneumoniae and N. meningitides (p < 0.0001). The overall mortality rate was 22.1%. The mortality rate for Streptococcus pneumoniae was 17.1%. The highest mortality was observed in patients with Pseudomonal meningitis where all four patients expired followed by mortality rate of 85.7% in Escherichia coli afflicted patients (p < 0.001). Complications occurred in 73 (37.6%) patients with persistent complications in 31 (42.4%) patients. Complications resolved in 34 (46.5%) patients. The most common complications were seizures (12.8%) and cranial nerve palsies (11.3%). Seizures were more likely to occur in older patients (p < 0.05) whereas hydrocephalus was more common in younger patients (p < 0.05). CONCLUSION Bacterial Meningitis remains a serious disease associated with substantial morbidity and mortality. Most cases are community acquired with S. Pneumoniae being the most common pathogen. Old age, diabetes mellitus, a positive culture, seizures as a complication and late stage in the disease are the important predictors of a poor outcome.
Collapse
|
154
|
Rekha T, Khan AA, Alavi A, Hussain MA, Habeeb A, Ahmed N, Habibullah CM. GENETIC FINE STRUCTURE ANALYSIS OF HELICOBACTER PYLORI ISOLATES BEFORE AND AFTER TREATMENT. Indian J Med Microbiol 2003. [DOI: 10.1016/s0255-0857(21)03066-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
155
|
Rekha T, Khan AA, Alavi A, Hussain MA, Habeeb A, Ahmed N, Habibullah CM. Genetic fine structure analysis of Helicobacter pylori isolates before and after treatment. Indian J Med Microbiol 2003; 21:166-71. [PMID: 17643012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
BACKGROUND Eradication of H. pylori infection cures peptic ulcer disease and conversely, relapse is associated with reappearance of H. pylori infection. However, it is not clear whether the recurrence of ulcers following H. pylori eradication is due to recrudescence (identical strain) of the previous infection or as a result of exogenous reinfection (different strain) by another strain. The aim of the present study was to analyze the FAFLP patterns of pre and post treatment H. pylori samples to check if the recurrence was due to recrudescence or reinfection. MATERIALS AND METHODS 24 of 30 duodenal ulcer (DU) subjects screened for H. pylori infection were positive for H. pylori infection. The treatment regime included pantoprazole, ciprofloxacin and amoxicillin. The patients were called for a repeat endoscopy after one month and screened for H. pylori infection. FAFLP analysis and PCR for the cagA and vacA gene was performed for the pre and post treatment samples. RESULTS Of the 24 positive H. pylori patients, only 6 were negative after treatment and the remaining 18 were positive for H. pylori infection. The analysis of the pre and post treatment samples of the 18 patients showed that the FAFLP profiles of the initial and follow-up pools were similar to one another. CONCLUSION It can be concluded that in the present series of patients, reinfection was due to recrudescence of infection due to incomplete eradication. The study also suggests that DNA fingerprinting by FAFLP provides discriminatory and complementary data for identifying strains of H. pylori while monitoring therapy.
Collapse
|
156
|
Khan AA, Khan SU, Hossain Z. Intrathoracic migration of a humeral orthopedic pin. THE JOURNAL OF CARDIOVASCULAR SURGERY 2003; 44:275-7. [PMID: 12813399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
Intrathoracic migration of orthopedic fixation pins occurs infrequently but can have dire consequences if not recognized. Described herein is the case of an orthopedic pin that migrated from the proximal humerus into lung parenchyma. After preoperative computed tomography and fluoroscopy, the pin was removed via thoracotomy.
Collapse
|
157
|
Nawaz MS, Khan SA, Khan AA, Nayak R, Steele R, Paine D, Jones R. Molecular characterization of fluoroquinolone-resistant Campylobacter spp. isolated from poultry. Poult Sci 2003; 82:251-8. [PMID: 12619802 DOI: 10.1093/ps/82.2.251] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Campylobacteriosis, an infectious disease caused by Campylobacter jejuni and Campylobacter coli, is treated by fluoroquinolone antibiotics in clinical practices. However, use of these drugs in animal husbandry may select for fluoroquinolone-resistant campylobacters and, thereby, compromise the clinical treatment of infection. In this study, 21 fluoroquinolone-resistant campylobacters were isolated from poultry samples. Morphological and biochemical characteristics indicated that 19 isolates were C. jejuni and two were C. coli. All isolates were resistant to multiple antibiotics but sensitive to chloramphenicol and gentamicin. These isolates were characterized at the molecular level by amplifying the flagellin gene (flaA) by PCR. The PCR protocol amplified a 1.7-kb flaA gene from all isolates. RFLP analysis of the 1.7-kb amplicons after digestion with DdeI yielded four distinct patterns. The 21 fluoroquinolone-resistant campylobacter isolates were further characterized by pulsed-field gel electrophoresis (PFGE) and compared with the PFGE patterns of nine fluoroquinolone-sensitive campylobacter strains. Four of the 21 fluoroquinolone-resistant isolates were untypable by the PFGE protocol. The PFGE analysis with SalI or SmaI indicated that seven or five, respectively, of the 17 resistant isolates had identical macrorestriction profiles (mrps). However, PFGE analysis with a combination of SalI and SmaI indicated that four of the 17 isolates had similar macrorestriction profiles. The PFGE patterns of the 17 fluoroquinolone-resistant isolates were different from the nine sensitive campylobacter strains.
Collapse
|
158
|
Khan AA, Shah SWH, Alam A, Butt AK, Shafqat F. Efficacy of Rigiflex balloon dilatation in 12 children with achalasia: a 6-month prospective study showing weight gain and symptomatic improvement. Dis Esophagus 2003; 15:167-70. [PMID: 12220427 DOI: 10.1046/j.1442-2050.2002.00246.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Achalasia cardia is a disease of adolescents and is rare in children. In total, 12 children with primary achalasia, with a mean age of 10.8 +/- 2 years, were prospectively evaluated for the efficacy of a 30-mm-diameter Rigiflex balloon for relief of symptoms and weight gain after 1 and 6 months of follow up. The 12 children were evaluated and treated for achalasia, with pneumatic balloon dilatation, from January 1998 to December 2000. They were studied for basal, 1-, and 6-month post-dilatation composite symptoms for dysphagia, regurgitation, night cough and heartburn. Basal and 5-min post-dilatation barium swallow were obtained to compare barium height and width for efficacy of dilatation and to evaluate for complications. There were no complications. Barium height, width, composite symptom score and weight improved significantly up to the 6-month follow up. Rigiflex balloon dilatation of 30-mm diameter is safe and effective in children with achalasia.
Collapse
|
159
|
Bhattacharya P, Jacks G, Ahmed KM, Routh J, Khan AA. Arsenic in groundwater of the Bengal delta plain aquifers in Bangladesh. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2002; 69:538-545. [PMID: 12232725 DOI: 10.1007/s00128-002-0095-5] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
160
|
Khan AA, Coppock RW, Schuler MM, Geleta L. Biochemical changes as early stage systemic biomarkers of petroleum hydrocarbon exposure in rats. Toxicol Lett 2002; 134:195-200. [PMID: 12191878 DOI: 10.1016/s0378-4274(02)00188-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Crude and refined petroleum contain a complex mixture of aliphatic, aromatic, polyaromatic and heterocyclic hydrocarbon compounds. The objective of our research was to investigate early-stage biochemical changes in rats exposed to low dosages of petroleum hydrocarbons. The animals were repeatedly exposed, per oral by gavage, to low dosages (0.5-2.5 ml/kg) of an Alberta crude oil (ACO) and their general health and systemic biochemical parameters were assessed. Rats exposed to these doses of ACO did not show any apparent symptoms of intoxication. Similarly, no significant changes were observed in clinical parameters of systemic impairment. Systemic biochemical assessment has shown that ACO exposure caused marked changes in the activities of several cytochrome P-450 (CYP)-linked polysubstrate monooxygenase enzymes in liver, kidney and lung tissues. Exposure to ACO caused dose-dependent increases in the hepatic activities of ethoxyresorufin-O-deethylase, a CYP 1A1/A2-linked enzyme; pentoxyresorufin-O-dealkylase, a CYP 2B-linked enzyme, and ethoxycoumarin-O-deethylase, a CYP 2B/1A-linked enzyme. Temporal assessment showed that these systemic biochemical changes were reversible in nature. Analysis of biomarker chemicals provided evidence that in exposed animals petroleum hydrocarbons were mainly distributed in the adipose tissues.
Collapse
|
161
|
Shakoor MA, Ahmed MS, Kibria G, Khan AA, Mian MAH, Hasan SA, Nahar S, Hossain MA. Effects of cervical traction and exercise therapy in cervical spondylosis. BANGLADESH MEDICAL RESEARCH COUNCIL BULLETIN 2002; 28:61-9. [PMID: 12825763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/21/2023]
Abstract
A randomised clinical trial was conducted in the Department of Physical Medicine, Chittagong Medical College Hospital from July, 2001 to June, 2002. The objectives of the study were to find out the effects of cervical traction (CT) and exercise on the patients with chronic cervical spondylosis. A total of 199 patients with cervical spondylosis were included in the clinical trial. One hundred patients were treated with cervical traction plus exercise and 99 patients were treated with non-steroidal anti-inflammatory drug (NSAID). Posture correction advice was given to all patients. The patients were treated for 6 weeks. There was a marked improvement in both the groups after treatment (P<0.001). But there was nearly significant difference regarding improvement in treatment with CT plus exercise than with NSAID (P = 0.06). The results indicate that the improvement of the patients with chronic cervical spondylosis was more in CT plus exercise than analgesics. So, CT & neck muscle strengthening exercise may have some more beneficial effects than NSAIDs on chronic cervical spondylosis.
Collapse
|
162
|
Walia S, Shi L, Khan AA, Joshi B, Chaudry GR. Sequence analysis and molecular characterization of a nitrocatechol dioxygenase gene from Pseudomonas putida. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2002; 37:379-391. [PMID: 12081029 DOI: 10.1081/pfc-120004478] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A Pseudomonas putida capable of degrading polychlorinated biphenyl was also found to transform 4-nitrocatechol to 3-nitro-2-hydroxy-6-oxohexa-2,4-dienoic acid (NHODA). Crude cell extract of this bacterium exhibited an enzyme (nitrocatechol dioxygenase, Ndo) activity catalyzing this transformation. The gene encoding Ndo was cloned in E. coli. The cloned gene (ndo) expressed in E. coli had enzyme activity that degraded not only 4-nitrocatechol but also 4-chlorocatechol, 4-methylcatechol, 2,3-dihydroxybiphenyl, and 4'-chloro-2,3-dihydroxybiphenyl. Nucleotide sequence analysis of the cloned ndo exhibited an open reading frame of 939 base pairs. This sequence can encode a 313 amino acids protein of approximately molecular weight of 35 kd, which was confirmed by in vitro transcription and translation assay and SDS-PAGE analysis. A putative ribosomal binding site (GAGGAGA) was present 7 base pairs upstream from the AUG start codon and a promotor site homologous to E. coli '-10' and '-35' regulatory region was located at '-123' and '-174' area of our clone with sequences of TTGAAG and GTGACA, respectively. The deduced amino acid sequence showed 69% homology with Cdo from Burkholderia cepacia AAI. A unique insertion of 21 amino acids was found towards the N-terminal of the Ndo. Expression of ndo in strain OU83 was repressed in presence of 3-chlorobenzoic acid as judged by the decrease in the expression of ndo specific transcript.
Collapse
|
163
|
Khan AA, Nawaz MS, Khan SA, Steele R. Detection and characterization of erythromycin-resistant methylase genes in Gram-positive bacteria isolated from poultry litter. Appl Microbiol Biotechnol 2002; 59:377-81. [PMID: 12111173 DOI: 10.1007/s00253-002-1013-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2001] [Revised: 03/13/2002] [Accepted: 03/22/2002] [Indexed: 10/27/2022]
Abstract
The epidemiology of four erythromycin-resistant methylase ( erm) genes, ermA, ermB, ermC and msrA, was determined in erythromycin-resistant staphylococci, enterococci and streptococci isolated from poultry litter. All isolates were resistant to multiple antibiotics. Southern hybridization indicated that 4 of the 20 staphylococci contained the ermC gene on plasmids: on a 2.2 kb plasmid in Staphylococcus hominis and S. sciuri, on a 6.0 kb plasmid in S. xylosus, and on a 7.0 kb plasmid in S. lentus. In 16 of the 20 staphylococci, the ermA gene was harbored exclusively on the chromosome, as a double chromosomal insert on 8.0 and 6.2 kb EcoRI fragments. None of the staphylococci harbored the msrA gene. Dot-blot analysis indicated that all enterococci and streptococci hybridized with a biotinylated ermB gene probe. Southern hybridization indicated that only 2 of the 19 erythromycin-resistant enterococci contained the ermB gene on plasmids. The gene was localized on 4.0 kb and 5.9 kb plasmids, respectively, in two Enterococcus faecium isolates. Results from our studies indicate that the patterns of occurrence of erm genes, the sizes of the plasmids and the copy numbers of the inserts were different from the existing information on the presence of erm genes in clinical strains of Staphylococcus spp.
Collapse
|
164
|
Butt AK, Khan AA, Khan AA, Izhar M, Alam A, Shah SWH, Shafqat F. Correlation of Helicobacter pylori in dental plaque and gastric mucosa of dyspeptic patients. J PAK MED ASSOC 2002; 52:196-200. [PMID: 12174490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
OBJECTIVE To establish the prevalence of Helicobacter pylori colonization of dental plaque and its correlation with Helicobacter pylori infection of the antral mucosa in patients with symptomatic dyspepsia. METHODS Seventy eight adult dyspeptic patients undergoing upper gastrointestinal tract endoscopy were prospectively enrolled. Four air dried dental plaque cytology slides and four gastric antral mucosal biopsies were stained with Giemsa stain. CLO test was used for detection of urease activity of Helicobacter pylori in the dental plaque specimens and antral mucosal biopsies. Data on endoscopic findings and orodental hygiene were recorded. RESULTS Dental plaque colonization using CLO test and cytology was found to be 100% and 88% respectively. Antral biopsy for H. pylori was positive in 61% cases by CLO test and 57% cases on histopathology. Forty four out of 69 patients (63%) had both dental plaque and antral biopsy positive for H. pylori. No patient with negative dental plaque cytology was positive for H. pylori in gastric mucosa. A statistically significant correlation was found between H. pylori colonization of dental plaque and gastric antrum. The sensitivity and specificity of dental plaque cytology in diagnosing H. pylori antral colonization was 100% and 26% while the positive and negative predictive values were 64% and 100% respectively. CONCLUSION The prevalence of H. pylori in dental plaque of patients with dyspepsia was very high in our patients indicating it to be a major reservoir of infection.
Collapse
|
165
|
Khan AA, Brown J, Faulkner K, Kendler D, Lentle B, Leslie W, Miller PD, Nicholson L, Olszynski WP, Watts NB, Hanley D, Hodsman A, Josse R, Murray TM, Yuen K. Standards and guidelines for performing central dual X-ray densitometry from the Canadian panel of International Society for Clinical Densitometry. J Clin Densitom 2002; 5:247-57. [PMID: 12357062 DOI: 10.1385/jcd:5:3:247] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2002] [Accepted: 03/04/2002] [Indexed: 11/11/2022]
Abstract
The International Society for Clinical Densitometry (ISCD) is a multidisciplinary nonprofit global organization formed to ensure excellence in densitometry imaging, interpretation, and application. The Canadian panel of the ISCD represents ISCD in Canada and oversees Canadian bone densitometry certification programs. The standards of care from the Canadian panel of the ISCD have been developed in order to establish the minimum level of acceptable performance for the practice of bone densitometry in Canada. A variety of techniques are available for skeletal assessment of bone mineral density, which vary in accuracy, precision, and clinical utility as well as availability. This article focuses on central dual X-ray absorptiometry in adults and does not address densitometry in the pediatric population. Other technologies will be addressed in a subsequent article.
Collapse
|
166
|
Khan AA, Brown J, Faulkner K, Kendler D, Lentle B, Leslie W, Miller PD, Nicholson L, Olszynski WP, Watts NB. Standards and guidelines for performing central dual X-ray densitometry from the Canadian Panel of International Society for Clinical Densitometry. J Clin Densitom 2002; 5:435-45. [PMID: 12665644 DOI: 10.1385/jcd:5:4:435] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2002] [Accepted: 03/04/2002] [Indexed: 11/11/2022]
Abstract
The International Society for Clinical Densitometry (ISCD) is a multidisciplinary nonprofit global organization formed to ensure excellence in densitometry imaging, interpretation, and application. The Canadian panel of the ISCD represents ISCD in Canada and oversees Canadian bone densitometry certification programs. The standards of care from the Canadian panel of the ISCD have been developed in order to establish the minimum level of acceptable performance for the practice of bone densitometry in Canada. A variety of techniques are available for skeletal assessment of bone mineral density, which vary in accuracy, precision, and clinical utility as well as availability. This article focuses on central dual X-ray absorptiometry in adults and does not address densitometry in the pediatric population. Other technologies will be addressed in a subsequent article.
Collapse
|
167
|
Khan AA, Nawaz MS, Robertson L, Khan SA, Cerniglia CE. Identification of predominant human and animal anaerobic intestinal bacterial species by terminal restriction fragment patterns (TRFPs): a rapid, PCR-based method. Mol Cell Probes 2001; 15:349-55. [PMID: 11851378 DOI: 10.1006/mcpr.2001.0383] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Identification of predominant human and animal intestinal tract anaerobes by conventional methods is cumbersome, time-consuming and less sensitive as compared to molecular methods. We have developed a molecular technique to identify most of the abundant intestinal microflora by polyermase chain reaction (PCR) amplification of a 16S rRNA gene fragment using a pair of universal PCR primers. The forward PCR primer was labelled with 6-carboxyfluorescein amino hexy (6-FAM) fluorescent dye to detect the terminal fragment of the PCR products after digestion with restriction enzymes. The PCR products were purified and digested with restriction enzymes and were analysed by capillary electrophoresis using an automated DNA sequencer. The data was analysed with GeneScan software 2.1. Eleven bacteria (Eubacterium biforme, E. limosum, Peptostreptococcus productus, Lactobacillus acidophilus, Bacteroides thetaiotaomicron, B. vulgatus, B. distasonis, Clostridium clostridiiforme, C. leptum, C. perfringens and Escherichia coli) that are predominant in human and animal intestinal tract were successfully identified by this rapid molecular technique. This protocol is rapid, accurate, sensitive and capable of identifying multiple organisms in a single sample.
Collapse
|
168
|
Wu J, Khan AA, Shih CY T, Shih DS. Cloning and sequence determination of a gene encoding an osmotin-like protein from strawberry (Fragaria X ananassa Duch.). DNA SEQUENCE : THE JOURNAL OF DNA SEQUENCING AND MAPPING 2001; 12:447-53. [PMID: 11913795 DOI: 10.3109/10425170109084473] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Osmotin and osmotin-like proteins (OLPs) are pathogenesis-related (PR) proteins, whose synthesis is normally stimulated upon infection of plants by pathogens. A strawberry genomic clone containing an osmotin-like protein (OLP) gene was isolated and sequenced. This clone contains an open reading frame of 681 nucleotides without any intron. The predicted amino acid sequence of the protein shares high degrees of homology with a number of other OLPs and related proteins, of which several are known to have antifungal activities. Southern hybridization analysis of strawberry genomic DNA suggested that the OLP is coded by a multi-gene family. Results from reverse transcriptase-polymerase chain reaction indicated that this OLP gene is expressed in uninfected strawberry plants.
Collapse
|
169
|
Dionne RA, Khan AA, Gordon SM. Analgesia and COX-2 inhibition. Clin Exp Rheumatol 2001; 19:S63-70. [PMID: 11695255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
While non-steroidal anti-inflammatory drugs (NSAIDs) are the mainstay of therapy for the management of acute pain and rheumatoid arthritis, toxicity associated with chronic administration limits their benefit-to-risk relationship in many patients. A series of studies is reviewed that assesses the relationship between cytokines released at the site of tissue injury and NSAID analgesia, and the in vivo selectivity of a selective cyclooxygenase (COX)-2 inhibitor (celecoxib) in comparison to a dual COX-1/COX-2 inhibitor (ketorolac). Three replicate studies in the oral surgery model of acute pain used submucosal microdialysis sample collection for the measurement of prostaglandin E2 (PGE2; a product of both COX-1 and COX-2) and thromboxane B2 (as a biomarker for COX-1 activity) with parallel assessments of pain. The time course of PGE2 production was consistent with early release due to COX-1 activity followed by increased production 2-3 hours after surgery, consistent with COX-2 expression. Ketorolac 30 mg at pain onset suppressed both pain and peripheral PGE2 levels. Ketorolac 1 mg either at the site of injury or intramuscularly also produced analgesia but without any effect on peripheral PGE2 levels. Celecoxib selectively suppressed PGE2 but not TxB2 at time points consistent with COX-2 activity, while producing analgesia. These studies demonstrate the ability to assess the time course and selective effects of COX-2 inhibitors in vivo and suggest that suppression of COX-2 mediated PGE2 is temporally related to NSAID analgesia.
Collapse
|
170
|
Khan AA, Wang RF, Cao WW, Doerge DR, Wennerstrom D, Cerniglia CE. Molecular cloning, nucleotide sequence, and expression of genes encoding a polycyclic aromatic ring dioxygenase from Mycobacterium sp. strain PYR-1. Appl Environ Microbiol 2001; 67:3577-85. [PMID: 11472934 PMCID: PMC93058 DOI: 10.1128/aem.67.8.3577-3585.2001] [Citation(s) in RCA: 164] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mycobacterium sp. strain PYR-1 degrades high-molecular-weight polycyclic hydrocarbons (PAHs) primarily through the introduction of both atoms of molecular oxygen by a dioxygenase. To clone the dioxygenase genes involved in PAH degradation, two-dimensional (2D) gel electrophoresis of PAH-induced proteins from cultures of Mycobacterium sp. strain PYR-1 was used to detect proteins that increased after phenanthrene, dibenzothiophene, and pyrene exposure. Comparison of proteins from induced and uninduced cultures on 2D gels indicated that at least six major proteins were expressed (105, 81, 52, 50, 43, and 13 kDa). The N-terminal sequence of the 50-kDa protein was similar to those of other dioxygenases. A digoxigenin-labeled oligonucleotide probe designed from this protein sequence was used to screen dioxygenase-positive clones from a genomic library of Mycobacterium sp. strain PYR-1. Three clones, each containing a 5,288-bp DNA insert with three genes of the dioxygenase system, were obtained. The genes in the DNA insert, from the 5' to the 3' direction, were a dehydrogenase, the dioxygenase small (beta)-subunit, and the dioxygenase large (alpha)-subunit genes, arranged in a sequence different from those of genes encoding other bacterial dioxygenase systems. Phylogenetic analysis showed that the large alpha subunit did not cluster with most of the known alpha-subunit sequences but rather with three newly described alpha subunits of dioxygenases from Rhodococcus spp. and Nocardioides spp. The genes from Mycobacterium sp. strain PYR-1 were subcloned and overexpressed in Escherichia coli with the pBAD/ThioFusion system. The functionality of the genes for PAH degradation was confirmed in a phagemid clone containing all three genes, as well as in plasmid subclones containing the two genes encoding the dioxygenase subunits.
Collapse
|
171
|
Burgess SS, Adams MA, Turner NC, Beverly CR, Ong CK, Khan AA, Bleby TM. An improved heat pulse method to measure low and reverse rates of sap flow in woody plants. TREE PHYSIOLOGY 2001; 21:589-598. [PMID: 11390303 DOI: 10.1093/treephys/21.9.589] [Citation(s) in RCA: 147] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The compensation heat pulse method (CHPM) is of limited value for measuring low rates of sap flow in woody plants. Recent application of the CHPM to woody roots has further illustrated some of the constraints of this technique. Here we present an improved heat pulse method, termed the heat ratio method (HRM), to measure low and reverse rates of sap flow in woody plants. The HRM has several important advantages over the CHPM, including improved measurement range and resolution, protocols to correct for physical and thermal errors in sensor deployment, and a simple linear function to describe wound effects. We describe the theory and methodological protocols of the HRM, provide wound correction coefficients, and validate the reliability and accuracy of the technique against gravimetric measurements of transpiration.
Collapse
|
172
|
Khan EI, Amjad N, Khan AA. Anaesthetic management for a patient with severe multiple sclerosis. J PAK MED ASSOC 2001; 51:231-3. [PMID: 11475781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
|
173
|
Khan AA, Bose C, Yam LS, Soloski MJ, Rupp F. Physiological regulation of the immunological synapse by agrin. Science 2001; 292:1681-6. [PMID: 11349136 DOI: 10.1126/science.1056594] [Citation(s) in RCA: 146] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
T cell activation is dependent on both a primary signal delivered through the T cell receptor and a secondary costimulatory signal mediated by coreceptors. Although controversial, costimulation is thought to act through the specific redistribution and clustering of membrane and intracellular kinase-rich lipid raft microdomains at the contact site between T cells and antigen-presenting cells. This site has been termed the immunological synapse. Endogenous mediators of raft clustering in lymphocytes have not been identified, although they are essential for T cell activation. We now demonstrate that agrin, an aggregating protein crucial for formation of the neuromuscular junction, is also expressed in lymphocytes and is important in reorganization of membrane lipid microdomains and setting the threshold for T cell signaling. Our data show that agrin induces the aggregation of signaling proteins and the creation of signaling domains in both immune and nervous systems through a common lipid raft pathway.
Collapse
|
174
|
El Sayed KA, Hamann MT, Hashish NE, Shier WT, Kelly M, Khan AA. Antimalarial, antiviral, and antitoxoplasmosis norsesterterpene peroxide acids from the Red Sea sponge Diacarnus erythraeanus. JOURNAL OF NATURAL PRODUCTS 2001; 64:522-524. [PMID: 11325240 DOI: 10.1021/np000529+] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A new norsesterterpene acid, named muqubilone (1), along with the known sigmosceptrellin-B and muqubilin were isolated from the Red Sea sponge Diacarnus erythraeanus. The structure determination of 1 was based primarily on 1D and 2D NMR analyses. Sigmosceptrellin-B exhibits significant in vitro antimalarial activity against Plasmodium falciparum (D6 and W2 clones) with IC(50) values of 1200 and 3400 ng/mL, respectively. Muqubilin and 1 show in vitro antiviral activity against herpes simplex type 1 (HSV-1) with ED(50) values of 7.5 and 30 microg/mL, respectively. Muqubilin and sigmosceptrellin-B display potent in vitro activity against Toxoplasma gondii at a concentration of 0.1 microM without significant toxicity.
Collapse
|
175
|
Khan AA, Coppock RW, Schuler MM. Effects of multiple exposures of small doses of Pembina Cardium crude oil and diesel in rats. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2001; 40:418-424. [PMID: 11443375 DOI: 10.1007/s002440010192] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2000] [Accepted: 09/15/2000] [Indexed: 05/23/2023]
Abstract
In lands used for agricultural purposes, petroleum- or diesel-contaminated wastes and accidental spills of crude oil at some drilling sites pose exposure risks for occupational public, livestock, and wildlife. This study has assessed the effects of an Alberta crude oil, Pembina Cardium crude oil (PCCO), and a commercial diesel fuel #2 (CDF-2) in Sprague-Dawley rats after repeated exposures at small dose levels. Rats were given by gavage on day 1, 3, 5, and 8 specified dosages of either the control vehicle, methylcellulose (MC) (1.25 ml/kg), or PCCO (0.25-1.25 ml/kg), or CDF-2 (1.25 ml/kg). Exposure of rats to these dose levels of the test substances caused no overt symptoms of intoxication. A small but statistically significant increase in liver somatic index was observed in rats exposed to 1.25 ml/kg doses of PCCO and CDF-2; however, kidney somatic index was not significantly affected by these treatments. Blood analyses for hematological and clinical indicators of systemic impairments did not show any significant changes (p > 0.05) between the control and PCCO- or CDF-2-exposed rats. Biochemical assessment of liver and kidney tissues showed that compared to the control group, the PCCO- and CDF-2-exposed groups had a marked and significant increase (p < 0.05) in the hepatic activity of ethoxyresorufin-O-deethylase (EROD, a cytochrome P-450 [CYP] 1A1/A2-linked enzyme). In PCCO-exposed rats, the induction of EROD was dose-dependent. Exposure of rats with PCCO and CDF-2 also caused dose-related increases from the unexposed (control) or MC dosed rats in (1) hepatic activities of aryl hydrocarbon hydroxylase (AHH, a CYP 1A1-linked enzyme), ethoxycoumarin-O-deethylase (ECOD, a CYP 2B/1A-linked enzyme), glutathione transferase (GT), and NADPH-catalyzed microsomal lipid peroxidation; and (ii) ECOD activity in kidneys. The induction of hepatic CYP-linked enzymatic activities by PCCO and CDF-2 could be due to de novo synthesis of selected isoforms, as evidenced by the relative differences in the inhibition of EROD activity with 7,8-benzoflavone or metyrapone.
Collapse
|
176
|
Khan SA, Khan AA, Nawaz MS, DePaola A, Andrews A, Cerniglia CE. DNA packaging and developmental intermediates of a broad host range Vibrio vulnificus bacteriophage 71A-6. Mol Cell Probes 2001; 15:61-9. [PMID: 11292322 DOI: 10.1006/mcpr.2000.0344] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The structural intermediates in the capsid assembly and DNA packaging pathway of Vibrio vulnificus bacteriophage 71A-6, a rod-shaped double-stranded DNA podovirus, were isolated by ultracentrifugation and studied by electron microscopy, SDS-PAGE and pulsed-field gel electrophoretic analysis. Bacteriophage 71A-6 synthesized rod-shaped capsids (mean length=200+/-8 nm; mean width=47+/-3 nm n=50) during its development. Several host proteins that probably help in the assembly and maturation of the capsids were attached to these capsids as spherical structures. A capsid-DNA or DNA packaging complex that consisted of the mature capsids, DNA and a 42.5-kDa protein was also isolated. The size of the capsids increased in length and decreased in width (mean length=220+/-8 nm; mean width=45+/-3 nm n=50) either during or after the DNA packaging. The capsid fractions contained about 12 phage structural proteins and eight host proteins. At least three proteins were tentatively identified: a 38.5-kDa major capsid protein, a 35.2-kDa tail protein and 42.5-kDa packaging initiator or terminator protein. The size of the bacteriophage 71A-6 genome was determined to be 143.0-kb by pulsed-field gel electrophoresis. The total mass of all the mature phage proteins corresponded to only 14.0% of the coding capacity of phage genome.
Collapse
|
177
|
El Sayed KA, Kelly M, Kara UA, Ang KK, Katsuyama I, Dunbar DC, Khan AA, Hamann MT. New manzamine alkaloids with potent activity against infectious diseases. J Am Chem Soc 2001; 123:1804-8. [PMID: 11456797 DOI: 10.1021/ja002073o] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The isolation of the new enantiomers of 8-hydroxymanzamine A (1), manzamine F (2), along with the unprecedented manzamine dimer, neo-kauluamine from an undescribed genus of Indo-Pacific sponge (family Petrosiidae, order Haplosclerida) is reported. The relative stereochemistry of neo-kauluamine was established through detailed analysis of NOE-correlations combined with molecular modeling. The significance of the manzamines as in vivo antimalarial agents with superior activity to the clinically used drugs artemisinin and chloroquine is discussed along with the activity in vitro against the AIDS-opportunistic infectious diseases tuberculosis and toxoplasmosis. Reexamination of the sponges identified as Prianos, and Pachypellina, in earlier publications has confirmed that these are members of the same genus as the sponge described here, but differ at the species level.
Collapse
|
178
|
Shih CY, Khan AA, Jia S, Wu J, Shih DS. Purification, characterization, and molecular cloning of a chitinase from the seeds of Benincasa hispida. Biosci Biotechnol Biochem 2001; 65:501-9. [PMID: 11330660 DOI: 10.1271/bbb.65.501] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A chitinase was purified from the seeds of Benincasa hispida, a medicinal plant also called white gourd, and a member of the Cucurbitaceae family. Purification was done by using a procedure consisting of only two fractionation steps: an acid denaturation step followed by ion-exchange chromatography. The sequence of the N-terminal forty amino acid residues was analyzed and the sequence indicated that the enzyme is a class III chitinase. The enzyme, which is a basic chitinase, is one of at least five chitinases detected in the seed extract of B. hispida. Like other class III chitinases, this enzyme also has lysozyme activity. A genomic clone of the gene encoding the enzyme was isolated and sequenced. The gene has the potential to encode a protein of 301 amino acid residues. The deduced amino acid sequence of the protein, as expected from the N-terminal amino acid sequence, shares high degrees of similarity with other class III chitinases.
Collapse
|
179
|
Khan AA, Kazmi K. Risk stratification after acute myocardial infarction. J PAK MED ASSOC 2001; 51:92-4. [PMID: 11321882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
|
180
|
Butt AK, Khan AA, Suleman BA, Bedi R. Randomized clinical trial of Helicobacter pylori from dental plaque. Br J Surg 2001; 88:206. [PMID: 11167867 DOI: 10.1046/j.1365-2168.2001.01684.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
181
|
Khan AA, Slifer TR, Araujo FG, Remington JS. Activity of gatifloxacin alone or in combination with pyrimethamine or gamma interferon against Toxoplasma gondii. Antimicrob Agents Chemother 2001; 45:48-51. [PMID: 11120943 PMCID: PMC90238 DOI: 10.1128/aac.45.1.48-51.2001] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The activity of gatifloxacin against Toxoplasma gondii, either alone or in combination with pyrimethamine or gamma interferon (IFN-gamma), was examined in vitro and in vivo. In vitro, gatifloxacin significantly inhibited intracellular replication of tachyzoites of the RH strain with a 50% inhibitory concentration of 0.21 microg/ml at 48 h after addition of the drug to the cultures. Toxicity for host cells was not observed at this concentration. A synergistic effect (combination indices < 0.5) was demonstrated in vitro following 48 h of treatment with the combination of gatifloxacin and pyrimethamine (1:1 ratio). Doses of gatifloxacin of 100 and 200 mg/kg of body weight/day administered orally to mice for 10 days resulted in significant (P values of 0.056 and <0.0001, respectively) prolongation in time to death following infection with a lethal inoculum of tachyzoites. A dose of 400 mg/kg resulted in 20% survival (P = 0.0001). Mortality was 100% in untreated control mice and in mice treated with 25 or 50 mg/kg/day. Treatment of infected mice with a combination of gatifloxacin at 200 mg/kg/day and pyrimethamine at 12.5 mg/kg/day resulted in 85% survival, whereas 100 and 80% of mice treated with gatifloxacin alone or pyrimethamine alone, respectively, died (P < 0.0001). Moreover, a gatifloxacin dose of 200 mg/kg/day administered orally for 10 days plus 2 microg of recombinant murine IFN-gamma/day administered intraperitoneally for 10 days resulted in significant survival compared with IFN-gamma alone (P < 0.0001) or gatifloxacin alone (P < 0.007).
Collapse
|
182
|
Akram DS, Qureshi H, Mahmud A, Khan AA, Kundi Z, Shafi S, Olowokure B, Weil J, Bock H, Yazdani I. Seroepidemiology of varicella-zoster in Pakistan. THE SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH 2000; 31:646-9. [PMID: 11414405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
The availability of safe and effective vaccines has renewed interest in the epidemiology of varicella worldwide. To date published data on the epidemiology of varicella in Pakistan is very scarce. Therefore, we conducted a study to determine the age-specific seroprevalence rate of varicella-zoster virus (VZV) antibodies in Pakistan. Between December 1997 and March 1998, 1,509 healthy volunteers aged between 1 month and 30 years were recruited from the Islamabad, Karachi, Lahore and Rawalpindi areas. Demographic information, socioeconomic status and past medical history were obtained by questionnaire. Serum samples were assayed for IgG antibodies against VZV by enzyme-linked immunosorbent assay. Overall 41.8% (600/1,435) of those tested were found to be seropositive for VZV antibodies. No difference was found in results obtained from the different cities. A higher seroprevalence was observed among women (45.2%) compared to men (39.6%). Seroprevalence rates increased with age and were 28.4% in those aged 0-5 years, 41.5% in the 6-10 year age group, 42.5% in the 11-15 year age group, 46.7% in the 16-20 year age group and 53.6% in those aged 21-30 years. Socioeconomic status was not a significant risk factor for VZV seropositivity. This is the first report of the seroepidemiology of VZV in Pakistan. The results indicate that seroprevalence of VZV increases with age in the Pakistani population studied. As in other tropical countries, there is greater susceptibility to varicella among the adolescent and young adult population. The results of this study suggest that these at-risk groups should be included in vaccination programs aimed at reducing the public health impact of varicella.
Collapse
|
183
|
Khan AA, Aoki S, Boyd G, Burkhalter R, Ejiri S, Fukugita M, Hashimoto S, Ishizuka N, Iwasaki Y, Kanaya K, Kaneko T, Kuramashi Y, Manke T, Nagai K, Okawa M, Shanahan HP, Ukawa A, Yoshie T. Dynamical quark effects on light quark masses. PHYSICAL REVIEW LETTERS 2000; 85:4674-4677. [PMID: 11082624 DOI: 10.1103/physrevlett.85.4674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2000] [Indexed: 05/23/2023]
Abstract
Light quark masses are calculated in lattice QCD with two degenerate flavors of dynamical quarks. The calculations are made with improved actions with lattice spacing a = 0.22-0.11 fm. In the continuum limit we find m(M&Smacr;)(ud)(2 GeV) = 3.44(+0.14)(-0.22) MeV using the pi and rho meson masses as physical input, and m(M&Smacr;)(s)(2 GeV) = 88(+4)(-6) MeV or 90(+5)(-11) MeV with the K or straight phi meson mass as additional input. The quoted errors represent statistical and systematic combined, the latter including those from continuum and chiral extrapolations, and from renormalization factors. Compared to quenched results, two flavors of dynamical quarks reduce quark masses by about 25%.
Collapse
|
184
|
Iyer RN, Khan AA, Gupta A, Vajifdar BU, Lokhandwala YY. L-carnitine moderately improves the exercise tolerance in chronic stable angina. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 2000; 48:1050-2. [PMID: 11310378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
OBJECTIVES To study the safety and efficacy (with reference to exercise ECG testing) of oral L-carnitine in chronic stable angina. METHODS Forty-seven patients, 30 men and 17 women, aged 56 +/- 8 years, were randomized to receive L-carnitine (n = 28) or placebo (n = 19) in the dose of 2 g/day for 3 months. The adjuvant treatment was not changed during the study. Patients were evaluated by computerized stress test (CST) done at the beginning and end of the trial. The parameters assessed were exercise duration, time to onset of ST changes, total ST score at peak exercise, rate-pressure product at peak exercise, and time needed for the ST changes to recover to baseline. RESULTS The two groups were comparable at the beginning of the study. There was no change in the CST parameters in the placebo group at the end of 3 months. In the L-carnitine group there was a statistically significant improvement in the exercise duration from 7.8 +/- 2.2 min to 8.6 +/- 1.8 min (p = 0.006) and in the time needed for the ST changes to revert to baseline from 7.2 +/- 3.9 min to 5.7 +/- 3.8 min (p = 0.019). No change was noted in the time to onset for ST depression, ST score and double product. There were no systemic adverse effects or coronary events in either group. CONCLUSION Oral L-carnitine is safe and moderately improves the duration of exercise and time to recovery of ST changes in patients with chronic stable angina.
Collapse
|
185
|
Khan AA, Eid RA, Hamdi A. Structural changes in the tunica intima of varicose veins: a histopathological and ultrastructural study. Pathology 2000; 32:253-7. [PMID: 11186421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Many factors have been implicated in the aetiology of varicose veins; however, there is ample evidence implicating that the defect is in the wall of the lower limb veins. In order to know the pathological changes in the tunica intima of varicose veins, the smooth muscle cells (SMCs), collagen and elastin of varicose and control patients were studied by light and electron microscopy. The morphological changes in the SMCs, collagen and elastin point to a possible secretory or phagocytic role of the SMCs in producing abnormal immature collagen or elastin fibres or in modulation of function of SMCs due to excessive production of extracellular matrix (ECM).
Collapse
|
186
|
Tahir MA, Herrera RJ, Khan AA, Kashyap VK, Duncan G, Barna C, Budowle B, Rowold DJ, Amjad M, Sinha S. Distribution of HLA-DQA1, polymarker, CSF1PO, vWA, TH01, TPOX, D16S539, D7S820, D13S317, and D5S818 alleles in East Bengali and West Punjabi populations from Indo-Pak Subcontinent. J Forensic Sci 2000; 45:1320-3. [PMID: 11110191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Blood samples were collected from 115 individuals residing in the Pakistani state of West Punjab and 81 Bengali individuals residing in the state of East Bengal, India. These samples were analyzed for the loci HLA-DQA1, PM (LDLR, GYPA, HBGG, D7S8, and GC) and eight short tandem repeats: CSF1PO, TPOX, THO1, vWA, D16S539, D7S820, D13S317, and D5S818. Departures from Hardy-Weinberg (HWE) were observed in Punjabi population at LDLR, THO1, D13S317, D5S818, and D16S539 and at CSF1PO and THO1 in Bengali population.
Collapse
|
187
|
Khan AA, Slifer TR, Araujo FG, Suzuki Y, Remington JS. Protection against lipopolysaccharide-induced death by fluoroquinolones. Antimicrob Agents Chemother 2000; 44:3169-73. [PMID: 11036044 PMCID: PMC101624 DOI: 10.1128/aac.44.11.3169-3173.2000] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Because fluoroquinolones have an immunomodulatory effect on cytokine production by lipopolysaccharide (LPS)-treated human monocytes, we examined the effect of fluoroquinolones on the survival of mice injected with a lethal dose of LPS. Trovafloxacin (100 mg/kg), ciprofloxacin (250 mg/kg), and tosufloxacin (100 mg/kg) protected 75% (P = 0.0001), 25% (P = 0.002), and 50% (P = 0.002), respectively, of mice against death. The fluoroquinolones significantly reduced serum levels of interleukin-6 and tumor necrosis factor alpha in LPS-treated mice. The protective effects of fluoroquinolones in LPS-induced shock in mice may also occur in humans.
Collapse
|
188
|
Wang RF, Wennerstrom D, Cao WW, Khan AA, Cerniglia CE. Cloning, expression, and characterization of the katG gene, encoding catalase-peroxidase, from the polycyclic aromatic hydrocarbon-degrading bacterium Mycobacterium sp. strain PYR-1. Appl Environ Microbiol 2000; 66:4300-4. [PMID: 11010873 PMCID: PMC92299 DOI: 10.1128/aem.66.10.4300-4304.2000] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A 81-kDa protein from Mycobacterium sp. strain PYR-1 was expressed in response to exposure of the strain to the polycyclic aromatic hydrocarbon pyrene and recovered by two-dimensional gel electrophoresis. The N-terminal sequence of the protein indicated that it was similar to catalase-peroxidase. An oligonucleotide probe designed from this sequence was used to screen a genomic library of Mycobacterium sp. strain PYR-1, and a positive clone, containing a part of the gene encoding the 81-kDa protein, was isolated. A gene-walking technique was used to sequence the entire gene, which was identified as katG for catalase-peroxidase. The deduced KatG protein sequence showed significant homology to KatGII of Mycobacterium fortuitum and clustered with catalase-peroxidase proteins from other Mycobacterium species in a phylogenetic tree. The katG gene was expressed in Escherichia coli to produce a protein with catalase-peroxidase activity. Since the induction of this catalase-peroxidase occurred in pyrene-induced cultures and the exposure of these cultures to hydrogen peroxide reduced pyrene metabolism, our data suggest that this enzyme plays a role in polycyclic aromatic hydrocarbon metabolism by strain PYR-1.
Collapse
|
189
|
Nawaz MS, Khan SA, Khan AA, Khambaty FM, Cerniglia CE. Comparative molecular analysis of erythromycin-resistance determinants in staphylococcal isolates of poultry and human origin. Mol Cell Probes 2000; 14:311-9. [PMID: 11040095 DOI: 10.1006/mcpr.2000.0320] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The ermA, ermB, ermC and msrA/msrB genes were detected in multidrug-resistant Staphylococcus spp. strains by PCR. Among 25 human clinical staphylococcal isolates the ermA, ermB, ermC and the msrA/msrB genes were detected in 88, 72, 4 and 100% of the strains, respectively. Among 24 poultry isolates the ermA, ermB, ermC and the msrA/msrB genes were detected in 100, 16.6, 50 and 12.5% of the strains, respectively. The ermA gene was found exclusively on the chromosome, whereas the ermC gene was found on 2.4-4.2 kb plasmids. Restriction fragment length polymorphism (RFLP) analysis of the ermA gene with Eco RI revealed five patterns (25.0, 21.0, 10.5, 6.2 and 4. 8 kb) for the clinical strains and two (8.0 and 6.2 kb) for the poultry strains. The 6.2 kb RFLP pattern, in both the poultry and human clinical isolates, indicates a common lineage for the ermA gene.
Collapse
|
190
|
Khan SA, Nawaz MS, Khan AA, Steele RS, Cerniglia CE. Characterization of erythromycin-resistant methylase genes from multiple antibiotic resistant Staphylococcus spp isolated from milk samples of lactating cows. Am J Vet Res 2000; 61:1128-32. [PMID: 10976747 DOI: 10.2460/ajvr.2000.61.1128] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To isolate and characterize erythromycin-resistant methylase genes in multiple-antibiotic resistant staphylococci isolated from milk samples. ANIMALS 300 lactating cows. PROCEDURE 23 erythromycin-resistant staphylococci were isolated from milk samples of 300 lactating cows. The prevalence of erythromycin-resistant methylase (erm) genes, ermC and ermA genes, and the multicomponent macrolide efflux pump in staphylococci msrA genes were identified and characterized by use of multiplex polymerase chain reaction (PCR), Southern hybridization, restricted fragment length polymorphism (RFLP) analysis, and dot-blot hybridization. RESULTS Biochemical characterization indicated that 3 of 23 (13%) isolates were coagulase-positive Staphylococcus aureus, and the rest were coagulase-negative. Multiplex PCR resulted in amplification of a 520-base pair (bp) region of the ermC gene from the cell lysates of a strain of S simulans M-21 and S sciuri M-28. The ermC gene in both isolates was found on a 3-kilobase plasmid. The ermA gene was found on the chromosome of 21 isolates, and 6 RFLP patterns were observed. None of the isolates harbored the msrA gene. CONCLUSIONS Erythromycin-resistant Staphylococcus spp isolated from milk samples of lactating cows may serve as reservoirs of erm genes homologous to those described in human isolates. However, the chromosomal insert patterns and prevalence of these genes, the sizes of plasmids harboring the genes, and the number of inserts of the genes (copy number) may differ from that of human isolates.
Collapse
|
191
|
Khan AA, Araujo FG, Craft JC, Remington JS. Ketolide ABT-773 is active against Toxoplasma gondii. J Antimicrob Chemother 2000; 46:489-92. [PMID: 10980181 DOI: 10.1093/jac/46.3.489] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
ABT-773 is active in vitro and in vivo against Toxoplasma gondii. It inhibited replication of RH strain tachyzoites in human foreskin fibroblasts. Mice infected intraperitoneally with tachyzoites and treated orally with 25, 50 or 100 mg/kg/day of ABT-773 for 10 days had 20% (P: = 0.016), 50% (P: = 0.003) and 100% (P: = 0.001) survival, respectively. Remarkable and highly significant survival was also noted in mice infected orally with strain C56 cysts and treated with ABT-773. Thus, ABT-773 may be useful for therapy of human toxoplasmosis.
Collapse
|
192
|
Wang RF, Cao WW, Khan AA, Cerniglia CE. Cloning, sequencing, and expression in Escherichia coli of a cytochrome P450 gene from Cunninghamella elegans. FEMS Microbiol Lett 2000; 188:55-61. [PMID: 10867234 DOI: 10.1111/j.1574-6968.2000.tb09168.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
A polyclonal antibody against microsomes of a fungus, Cunninghamella elegans, was used to screen a C. elegans cDNA library. A cDNA clone, containing an open reading frame (ORF) encoding a protein of 389 amino acids (aa), was obtained. GenBank comparison (BLAST) showed that the protein was closely related to P450 because a heme-binding region, which is highly conserved in all P450 sequences, was found in the ORF protein. Using an oligo probe designed from this C. elegans heme-binding region to rescreen the cDNA library, we obtained three new clones. Sequence comparison showed that the three clones, with different length cDNA inserts, were from the same mRNA of the C. elegans P450 gene. One clone had the full C. elegans P450 gene, encoding 473 aa with a molecular mass of 54958.60, whereas the 389 was a part of the 473 aa without the N-terminal. The entire C. elegans P450 gene was successfully subcloned and overexpressed in a plasmid-Escherichia coli system (pQE30). Immunostaining with three antibodies (CYP1A1, CYP2E1, and CYP3A1) against mammalian P450 enzymes and benzidine staining for hemoproteins showed positive results for the recombinant protein expressed in E. coli. A phylogenetic tree was constructed by comparison of other fungal P450s to the C. elegans sequence. The C. elegans P450 clustered close to the cyp51 family and was named cyp509A1 by the International Committee on the Nomenclature for Cytochrome P450 Enzymes.
Collapse
|
193
|
Blackshaw S, Sawa A, Sharp AH, Ross CA, Snyder SH, Khan AA. Type 3 inositol 1,4,5-trisphosphate receptor modulates cell death. FASEB J 2000; 14:1375-9. [PMID: 10877830 DOI: 10.1096/fj.14.10.1375] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Mechanisms accounting for the cellular entry of calcium that mediates cellular proliferation and apoptosis have been obscure. Previously we reported selective augmentation of type 3 inositol (1,4,5) trisphosphate receptors (IP(3)R3) in lymphocytes undergoing programmed cell death, which was prevented by antisense constructs to IP(3)R3. We now report increases in mRNA and protein levels for IP(3)R3 associated with cell death in several apoptotic paradigms in diverse tissues. Elevations of IP(3)R3 occur during developmental apoptosis in early postnatal cerebellar granule cells, dorsal root ganglia, embryonic hair follicles, and intestinal villi. Neurotoxic damage elicited by the glutamate agonist kainate is also associated with IP(3)R3 augmentation. In chick dorsal root ganglia neurons undergoing apoptosis due to deprivation of nerve growth factor, levels of IP(3)R3 are selectively increased and cell death is selectively prevented by antisense oligonucleotides to IP(3)R3. Thus, IP(3)R3 appears to participate actively in cell death in a diversity of tissues.
Collapse
MESH Headings
- Animals
- Apoptosis/drug effects
- Apoptosis/physiology
- Calcium Channels/genetics
- Calcium Channels/metabolism
- Chick Embryo
- Ganglia, Spinal/cytology
- Ganglia, Spinal/drug effects
- Ganglia, Spinal/metabolism
- Gene Expression Regulation, Developmental
- Inositol 1,4,5-Trisphosphate/metabolism
- Inositol 1,4,5-Trisphosphate Receptors
- Kainic Acid/pharmacology
- Nerve Growth Factor/pharmacology
- Neurons/cytology
- Neurons/drug effects
- Neurons/metabolism
- Oligonucleotides, Antisense/pharmacology
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Cytoplasmic and Nuclear/metabolism
- Tissue Distribution
Collapse
|
194
|
Khan AA, Slifer TR, Araujo FG, Remington JS. Effect of quinupristin/dalfopristin on production of cytokines by human monocytes. J Infect Dis 2000; 182:356-8. [PMID: 10882624 DOI: 10.1086/315655] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2000] [Revised: 03/22/2000] [Indexed: 11/03/2022] Open
Abstract
The effect of the novel streptogramin antibiotic quinupristin/dalfopristin (synercid) on cytokine production in vitro was examined in monocytes obtained from healthy human volunteers and stimulated with either lipopolysaccharide or heat-killed Staphylococcus aureus (Pansorbin). Synercid at concentrations that are achievable in humans (1, 5, and 10 microgram/mL) significantly suppressed production of interleukin (IL)-1alpha, IL-1beta, IL-6, IL-10, granulocyte-macrophage colony-stimulating factor, and tumor necrosis factor-alpha in a concentration-dependent manner. Thus, synercid possesses significant immunomodulatory activity, in addition to its antimicrobial activity.
Collapse
|
195
|
Ahmed M, Khan AA, Siddiqi T, Ikram M, Mian MY. A comparison of dissection-method and diathermy tonsillectomies. J PAK MED ASSOC 2000; 50:215-6. [PMID: 10992695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
OBJECTIVE To compare the dissection and diathermy methods of tonsillectomy and evaluate their advantages and disadvantages during surgery and convalescence. METHODS AND SETTING Patients who had tonsillectomy at Aga Khan University Hospital, between January 1994-December 1997. RESULTS Four year retrospective analysis was done of 200 patients who underwent tonsillectomy by either electrocautery or dissection method. One hundred and eleven underwent tonsillectomy by electrocautery and the other 79 had their tonsils removed by dissection-method and 2 had a combination of both. The average intra-operative blood loss was 10 ml with cautery and 65 ml with dissection method. The average operative time was 15.7 minutes with cautery and 26.9 minutes for dissection. We found higher amounts of blood loss and intra-operative time with dissection method than electrocautery. In comparing diathermy dissection method tonsillectomies, there was marked diffference between two, in peri-operative blood loss and operative time. CONCLUSION Although post-operative bleeding, pain and infection are complications of both techniques and in our study their incidence in similar in both, but intra-operative blood loss and time are two important factors, based on which we can conclude that electrocautery technique is a more effective technique in our set up.
Collapse
|
196
|
Abstract
Numerous investigators have studied and reported the antigenic reactivity of venoms from the species of snakes belonging to a genus or a family. However, there is very little published data on the inter-family antigenic cross reactivity among the venoms of snakes and absolutely no data on venoms from other sources such as honey bee, scorpion and toad. This report describes the antigenic and immunological cross reactivity among the venoms of snakes from major families: Crotalidae, Elapidae, Viperidae, Hydrophiidae and venoms from honey bee, scorpion and toad. The homologous polyclonal antisera versus snake venoms showed high reactivity to the respective venoms and varying degree to other venoms revealing the inter-family antigenic cross-reactivity. Surprisingly, venoms from bee, scorpion and toad showed antigenic cross reactivity to snake venoms. Antisera against snake venoms reacted immunologically to venoms from bee and scorpion but toad venom reacted only to anti C. atrox venom. The immunological cross reactivity among singular toxins, cobratoxin, ricin A, botulinum A and cholera was studied by using respective polyclonal antibodies. Immunological high cross reactivity was observed between bee venom and anti ricin, similarly between anti botulinum and cobratoxin. Bee venom reacted immunologically to all anti-toxins.
Collapse
|
197
|
Khan AA, Bergstrom GC, Nelson JC, Sorrells ME. Identification of RFLP markers for resistance to wheat spindle streak mosaic bymovirus (WSSMV) disease. Genome 2000; 43:477-82. [PMID: 10902711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Wheat spindle streak mosaic bymovirus (WSSMV) causes an economically important disease of winter wheat in Europe and North America. Artificial inoculation with this virus to identify resistant wheat genotypes is difficult. This study was conducted to identify restriction fragment length polymorphism (RFLP) markers associated with resistance to this disease. A population, consisting of 104 F5 recombinant inbred lines from a cross between hexaploid Triticum aestivum cultivars 'Geneva' (resistant) and 'Augusta' (susceptible), was evaluated for WSSMV symptoms under field conditions for four years. Two linked markers on the long arm of chromosome 2D, Xbcd1095 and Xcdo373, were determined to be associated with WSSMV resistance by bulked segregant analysis of the 10 most resistant and 10 most susceptible lines. Marker Xcdo373 accounted for 79% and Xbcd1095 for 73% of the phenotypic variation. Our results suggest that resistance to WSSMV in this population is qualitative in nature and is controlled by few genes. These markers should be useful in the development of wheat cultivars resistant to WSSMV and perhaps also to wheat yellow mosaic bymovirus (WYMV).
Collapse
|
198
|
Khan SA, Nawaz MS, Khan AA, Cerniglia CE. Transfer of erythromycin resistance from poultry to human clinical strains of Staphylococcus aureus. J Clin Microbiol 2000; 38:1832-8. [PMID: 10790109 PMCID: PMC86602 DOI: 10.1128/jcm.38.5.1832-1838.2000] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The transfer of ermA and ermC genes, the two most common resistance determinants of erythromycin resistance, was studied with Luria-Bertani broth in the absence of additional Ca(2+) or Mg(2+) ions. Fifteen human and five poultry isolates of Staphylococcus aureus, which were resistant to erythromycin but carried different genetic markers for erythromycin resistance, were used for conjugation. Since both the donors (Amp(s)-Tet(r)) and recipients (Amp(r)-Tet(s)) were resistant to erythromycin, the transconjugants were initially picked up as ampicillin- and tetracycline-resistant colonies. The resistance transfer mechanisms of the chromosomally located erythromycin rRNA methylase gene ermA and the plasmid-borne ermC gene were monitored by a multiplex PCR and gene-specific internal probing assay. Four groups of transconjugants, based upon the transfer of the ermA and/or ermC gene, were distinguished from each other by the use of this method. Selective antibiotic screening revealed only one type of transconjugant that was resistant to ampicillin and tetracycline. A high frequency of transfer (4.5 x 10(-3)) was observed in all of the 23 transconjugants obtained, and the direction of tetracycline and erythromycin resistance marker transfer was determined to be from poultry to clinical isolates. The transfers of the ermA and ermC genes were via transposition and transformation, respectively.
Collapse
|
199
|
San Pedro EC, Mountz JM, Ojha B, Khan AA, Liu HG, Kuzniecky RI. Anterior cingulate gyrus epilepsy: the role of ictal rCBF SPECT in seizure localization. Epilepsia 2000; 41:594-600. [PMID: 10802766 DOI: 10.1111/j.1528-1157.2000.tb00214.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PURPOSE The goal of this report is to demonstrate the utility of ictal brain single photon emission tomography (SPECT) in a 39-year-old man with complex partial seizures arising from the anterior cingulate gyrus. Seizures originating from the anterior cingulate gyrus are difficult to localize because they have variable ictal semiology, are usually brief, and have rapid cortical propagation. METHODS Clinical neurologic examination, electroencephalography, extended video-electroencephalography with scalp and sphenoidal electrodes, magnetic resonance imaging, computed tomography, and ictal brain SPECT with Tc-99m HMPAO were performed to identify the seizure focus. The patient's regional cerebral blood flow (rCBF) findings were compared with those of eight normal controls, and changes in rCBF were assessed by comparing the patient's ictal scan with those of normal controls at rest by using statistical parametric mapping (SPM). RESULTS Clinical and neurologic evaluations failed to demonstrate the epileptogenic focus. Ictal rCBF brain SPECT showed a focal region of hyperperfusion in the anterior cingulate gyrus. By using SPM, the ictal blood flow increase in the right anterior cingulate gyrus (x, y, z, -6, 42, 24 mm) was found to be statistically significant when compared with normal controls (z score, 4.88, p < 0.001). Subdural EEG recordings with intracranial electrodes positioned over this location confirmed that the cingulate gyrus was the origin of the seizures, and surgical resection resulted in >90% seizure reduction. CONCLUSIONS We concluded that ictal brain SPECT localization in conjunction with subdural electrode confirmation is a useful test in the presurgical evaluation of difficult to localize cingulate epilepsy.
Collapse
|
200
|
Khan AA, Nawaz MS, Khan SA, Cerniglia CE. Detection of multidrug-resistant Salmonella typhimurium DT104 by multiplex polymerase chain reaction. FEMS Microbiol Lett 2000; 182:355-60. [PMID: 10620692 DOI: 10.1111/j.1574-6968.2000.tb08921.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Salmonella typhimurium definitive type 104 (DT104) is a virulent pathogen for humans and animals with many strains having multiple drug resistance characteristics. The organism typically carries resistance to ampicillin, chloramphenicol, florfenicol, streptomycin, sulfonamides, and tetracycline (ACSSuT-resistant). A multiplex PCR method was developed to simultaneously amplify four genes, florfenicol (flo(st)), virulence (spvC), invasion (invA), and integron (int) from S. typhimurium DT104 (ACSSuT-type). Twenty-two ACSSuT-resistant DT104 isolates in our collection gave 100% positive reactions to this PCR assay by amplifying 584-, 392-, 321- and 265-bp PCR products, using primers specific to the respective target genes. One Salmonella strain DT23, ACSSuT-resistant, phage type 711 failed to amplify the 584-bp fragment, indicating that this method is specific for DT104-type ACSSuT-resistant S. typhimurium strains. One clinical and one bovine ASSuT-resistant strains that were sensitive to chloramphenicol and florfenicol did not yield a 584-bp fragment, indicating the absence of the flo(st) gene. This method will be useful for rapid identification of ACSSuT-type DT104 strains from clinical, food and environmental samples.
Collapse
|