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  Citation statistics : Table of Contents
   2013| January-March  | Volume 31 | Issue 1  
    Online since March 15, 2013

 
 
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BRIEF COMMUNICATIONS
Evaluation of antigenicity and cell mediated immunity of Hepatitis E virus patients: Using non radioactive MTT assay
M Majumdar, R Ratho, Y Chawla, MP Singh
January-March 2013, 31(1):64-68
DOI:10.4103/0255-0857.108725  PMID:23508432
Hepatitis E virus (HEV) is an important cause of hepatitis in developing nations. Disease spans from asymptomatic infection to acute viral hepatitis (AVH) and acute liver failure (ALF). Cell-mediated immunity (CMI) is less studied. Studies document CMI in HEV patients using [ 3 H]-thymidine incorporation (radioactive in nature). The aim of this study was to evaluate the antigenicity of recombinant HEV ORF 2 peptide (452-617 a.a) (pORF2) by non-radioactive MTT assay and detecting the proliferation indices of primary PBMC culture. A total of 27 laboratory confirmed HEV patients (16 AVH and 11 ALF) and 20 apparently healthy individuals (HC) were included. PBMCs were isolated, plated and stimulated with pORF2. After an incubation of 4 days, cells were looked for blastogenic transformation and subjected to MTT assay. PI of AVH, ALF and healthy controls were found to be 3.249 ± 0.219, 1.748 ± 0.076 and 0.226 ± 0.017, respectively. PI of AVH Vs HC, ALF Vs HC and AVH Vs ALF were found to be significantly higher ( P < 0.0001). This study demonstrates MTT to be an adaptable technique to evaluate CMI in HEV patients. Recombinant pORF2 was found to be antigenic in nature and PBMCs from AVH patients were immunologically more reactive than ALF patients.
  5 3,029 147
Analysis of carbapenem-resistant Acinetobacter from a tertiary care setting in North India
N Sinha, J Agarwal, S Srivastava, M Singh
January-March 2013, 31(1):60-63
DOI:10.4103/0255-0857.108724  PMID:23508431
Multidrug-resistant (MDR) Acinetobacter baumannii is a worldwide concern as cause of serious nosocomial infections. We analysed 140 non-duplicate Acinetobacter sp. isolates from hospitalised patients in a tertiary care centre; 87% were MDR and 20% (28/140) meropenem resistant. Metallo-β-lactamase was produced by 16 of these, detected by ethylene-diamine-tetra-acetic acid disc synergy test. AmpC β-lactamase and efflux pump were present in 17 and 4 of the meropenem-resistant Acinetobacter, respectively. 9/16 MBL-positive isolates carried genes for carbapenem resistance as shown by polymerase chain reaction.
  3 3,602 582
ORIGINAL ARTICLES
Variables affecting the performance of galactomannan assay in high-risk patients at a Tertiary Care Centre in India
S Khanna, JK Oberoi, S Datta, S Aggarwal, C Wattal
January-March 2013, 31(1):34-39
DOI:10.4103/0255-0857.108717  PMID:23508427
Background: Diagnosis of invasive aspergillosis (IA) in immunocompromised patients using galactomannan ELISA (GM-ELISA) has shown variable sensitivity and specificity. Objectives: To assess the diagnostic performance of GM-ELISA and analyze the effect of decreasing the cut off value, neutropenia, antifungals and piperacillin-tazobactam (PTZ). Prognostic value using 30 day all-cause mortality was also determined. Materials and Methods: Serum samples from 81 patients categorized into "proven," "probable," and "possible," categories based on revised EORTC/MSG definitions were tested by GM-ELISA. Results: Sensitivity of GM-ELISA in proven, probable and possible cases was 91.7%, 84.6% and 83.3% respectively. At an index cut-off value of 0.5 an increased sensitivity with minimal loss of specificity was observed. Use of antifungals demonstrated a decrease in sensitivity in proven and possible cases whereas it remained unaffected in probable category. Specificity increased from 75% to 100% with a positivity criterion of >2 consecutive samples. Although an increase in specificity was observed in patients not receiving PTZ, it was not statistically significant. Serial GM index values increased significantly in neutropenic patients and were associated with a poor prognosis. Conclusions: GM-ELISA may be a useful diagnostic and prognostic modality for the detection of IA in high risk patients.
  3 2,936 271
Changing patterns and trends of multidrug-resistant tuberculosis at referral centre in Northern India: A 4-year experience
AK Maurya, AK Singh, M Kumar, J Umrao, S Kant, VL Nag, RAS Kushwaha, TN Dhole
January-March 2013, 31(1):40-46
DOI:10.4103/0255-0857.108720  PMID:23508428
Purpose: India has a high burden of drug-resistant tuberculosis (TB), although there is little data on multidrug-resistant tuberculosis (MDR-TB). Although MDR-TB has existed for long time in India, very few diagnostic laboratories are well-equipped to test drug sensitivity. The objectives of this study were to determine the prevalence of MDR-TB, first-line drug resistance patterns and its changing trends in northern India in the 4 years. Materials and Methods: This was a prospective study from July 2007 to December 2010. Microscopy, culture by Bactec460 and p-nitro-α-acetylamino-β-hydroxypropiophenone (NAP) test was performed to isolate and identify Mycobacterium tuberculosis (M. tb) complex (MTBC). Drug sensitivity testing (DST) was performed by 1% proportional method (Bactec460) for four drugs: Rifampicin, isoniazid, ethambutol and streptomycin. Various clinical and demographical profiles were evaluated to analyse risk factors for development of drug resistance. Results: We found the overall prevalence rate of MDR-TB to be 38.8%, increasing from 36.4% in 2007 to 40.8% in 2010. we found that the prevalence of MDR-TB in new and previously treated cases was 29.1% and 43.3% ( P < 0.05; CI 95%). The increasing trend of MDR-TB was more likely in pulmonary TB when compared with extra-pulmonary TB ( P < 0.05; CI 95%). Conclusions: we found a high prevalence (38.8%) of MDR-TB both in new cases (29.1%) and previously treated cases (43.3%).This study strongly highlights the need to make strategies for testing, surveillance, monitoring and management of such drug-resistant cases.
  3 5,265 542
Detection of plasmid-mediated AmpC β-lactamase in Escherichia coli and Klebsiella pneumoniae
NO Yilmaz, N Agus, E Bozcal, O Oner, A Uzel
January-March 2013, 31(1):53-59
DOI:10.4103/0255-0857.108723  PMID:23508430
Background: Detecting plasmid-mediated AmpC (pAmpC) β-lactamase-producing organism is important for optimal infection control and providing accurate and effective treatment option for physicians. Objectives: The aim of this study was to investigate the prevalence of pAmpC β-lactamase and compare the results of boronic acid (BA) disk test with other phenotypic tests detecting AmpC positive isolates. Materials and Methods: A total of 273 clinical isolates of Klebsiella pneumoniae (n: 82) and Escherichia coli (n: 191) were analysed. The presence of pAmpC β-lactamase was determined by BA disk test, cefoxitin (FOX) screening test, modified three dimensional test (M3DT), and multiplex polymerase chain reaction (PCR). Pulsed-field gel electrophoresis was performed to evaluate the genetic similarities between isolates. To detect extended spectrum β-lactamases (ESBL) in the presence of AmpC β-lactamase, ESBL confirmation test was carried out with and without BA solution. Results: Of the 273 strains tested, 127 strains were found FOX resistant, 114 were positive by M3DT, 108 were positive in BA disk test, and the multiplex PCR detected 24 pAmpC β-lactamase-positive isolate. The prevalence of AmpC-producing strains was 10.9% in E. coli and 3.6% in K. pneumoniae in the tested population by PCR. CIT and MOX group genes were predominant type in these strains. Conclusion: These results emphasize that clinical laboratories should consider testing the presence of pAmpC enzymes particularly in FOX-resistant isolates, and BA disk test will improve detection of this emerging resistance phenotype.
  3 6,467 587
BRIEF COMMUNICATIONS
Outbreak of scrub typhus in the North East Himalayan region-Sikkim: An emerging threat
S Gurung, J Pradhan, PY Bhutia
January-March 2013, 31(1):72-74
DOI:10.4103/0255-0857.108729  PMID:23508434
Scrub typhus is an acute febrile illness that is known to be endemic in the South East Asian countries and the Western Pacific region. We here report an outbreak in the tiny Himalayan state of Sikkim. Patients with pyrexia of unknown origin were evaluated. They were screened by Weil-Felix test and the rapid immunochromatographic method. Samples that were positive by either Weil-Felix agglutination test or by rapid immunochromatography were confirmed by IgM enzyme-linked immunosorbent assay (ELISA). A total 204 samples were screened. Sixty-three patients were confirmed positive among which 42 were male and 21 were female. Effective management and early administration of antibiotics will help prevent the complications and mortality associated with scrub typhus.
  2 4,321 446
CASE REPORTS
Cryptococcus laurentii Fungemia
P Banerjee, M Haider, V Trehan, B Mishra, A Thakur, V Dogra, P Loomba
January-March 2013, 31(1):75-77
DOI:10.4103/0255-0857.108731  PMID:23508435
In the last few years there has been an increasing incidence of infection due to non-neoformans Cryptococcus spp. especially in immunocompromised host. Cryptococcus laurentii is a non-neoformans Cryptococcus which has rarely been known to cause bacteremia and pulmonary infection in humans. Here we report a case of fungemia due to Cryptococcus laurentii.
  2 10,427 244
ORIGINAL ARTICLES
A new approach of real time polymerase chain reaction in detection of vancomycin-resistant enterococci and its comparison with other methods
A Tripathi, SK Shukla, A Singh, KN Prasad
January-March 2013, 31(1):47-52
DOI:10.4103/0255-0857.108721  PMID:23508429
Background: Vancomycin-resistant enterococci (VRE) are third leading cause of nosocomial infection. Therefore, an effective, accurate and early detection of VRE along with their minimum inhibitory concentrations (MICs) is required to initiate appropriate therapy and thus better patient outcome. Objective: To detect VRE by real time quantitative polymerase chain reaction (Q-PCR) and to compare the results with chrom ID (C-ID) VRE and PCR. Further the study also determined the fold change of vanA gene by Q-PCR in different groups of VRE isolates classified on the basis of glycopeptides MIC range. Subjects and Methods: A total of 145 (80 VRE and 65 vancomycin-susceptible enterococci) clinical isolates were included in the study. After the screening of VRE isolates MICs were determined by E-test and agar dilution method. Further VRE was confirmed by vanA and vanB specific PCR and Q-PCR. Results: The sensitivity and specificity of C-ID VRE was 100% and 95.38%. However, sensitivity and specificity of conventional and Q-PCR were found to be 100%. Conventional and Q-PCR confirmed that our all isolates were vanA type. Mean R value was significantly higher ( P < 0.001) in group I (MIC > 1024 μg/ml) when compared to group II (MIC 512-1024 μg/ml) and group III (MIC < 512 μg/ml) isolates. The mean R was also significantly higher in group II when compared to group III isolates ( P = 0.038). Conclusion: Q-PCR is a rapid technique to detect vanA in enterococci along with their MIC range, thus it might be helpful to decide the treatment modalities of infections caused by VRE.
  2 3,343 401
Comparison of two recombinant systems for expression of cholera toxin B subunit from Vibrio cholerae
M Boustanshenas, B Bakhshi, M Ghorbani, D Norouzian
January-March 2013, 31(1):10-14
DOI:10.4103/0255-0857.108705  PMID:23508422
Purpose: The aim of this study was to assess the production of recombinant cholera toxin B subunit (rCTB) protein in two different expression systems (pAE_ctxB and pQE_ctxB constructs) in Escherichia coli BL21 (DE3). Materials and Methods: The ctxB fragment was amplified from Vibrio cholerae O 1 ATCC14035 and cloned in pGETM-T easy vector after which it was transformed to E. coli Top 10F' and grown on LB-ampicillin agar medium. Sequence analysis confirmed the complete ctxB gene sequence in the construct which was further subcloned to pQE-30 vector. The construct was subsequently transformed to E. coli M15 (pREP4). The recombinant pAE_ctxB and pQE_ctxB were transformed to competent E. coli BL21 (DE3) cells to express CTB protein. Result: Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed the maximum expression of rCTB in both systems at 5 h after induction and western blot analysis confirmed the presence of recombinant CTB in blotting membranes. Conclusion: Expression of rCTB in pAE_ctxB construct was more efficient (15-fold) than pQE_ctxB, and it seems that Lac UV5 in E. coli BL21 (DE3) is more compatible with the former construct. This expression system can be used to produce recombinant CTB in high yield which may enable us to study the oral tolerance or mucosal adjuvant properties of rCTB using animal models.
  2 5,931 203
Prevalence of biofilm-producing Staphylococcus epidermidis in the healthy skin of individuals in Tamil Nadu, India
CA EL Farran, A Sekar, A Balakrishnan, S Shanmugam, P Arumugam, J Gopalswamy
January-March 2013, 31(1):19-23
DOI:10.4103/0255-0857.108712  PMID:23508424
Purpose: Staphylococcus epidermidis is a major commensal bacteria. Various strains of S. epidermidis are capable of forming biofilms by attaching to several surfaces. Biofilm-forming ability of this organism is found to be associated with many hospital-acquired infections and can even impair wound healing. S. epidermidis strains producing polysaccharide-biofilms possess the intercellular adhesion (ica) operon while strains forming the protein adhesion-mediated biofilms possess the accumulation associated protein (aap) gene. We screened for biofilm-forming S. epidermidis in the skin of healthy individuals in Tamil Nadu in order to determine the risk of acquiring S. epidermidis infections in hospital settings. Materials and Methods: Skin swabs were taken from seventy two subjects residing in Chennai with healthy skin who showed no visible signs of skin lesions or allergies. S. epidermidis was isolated from 58 samples out of the 72 collected. The presence of ica operon in S. epidermidis isolates was determined by PCR and biofilm production was examined using quantitative tissue culture plate assay. Results: Majority of the samples (47/72; 65.3%) showed pure S. epidermidis growth, (14/72; 19.4%) showed pure Staphylococcus aureus growth and the remainder (11/72; 15.3%) showed mixed growth. Biofilm-forming S. epidermidis were found in the majority of samples (53/58; 91.4%) and ica operon was detected in 19 samples out of 58 (32.8%) which is a significantly higher percentage when compared to other studies conducted at different parts of the globe ( P = 0.0003). Conclusion: We inferred that ica operon and biofilm-forming S. epidermidis are common in the healthy skin of individuals in Tamil Nadu. Measures have to be taken to reduce the risk of hospital-acquired S. epidermidis infections.
  2 4,129 602
Multiple virulence factors regulated by quorum sensing may help in establishment and colonisation of urinary tract by Pseudomonas aeruginosa during experimental urinary tract infection
P Gupta, RK Gupta, K Harjai
January-March 2013, 31(1):29-33
DOI:10.4103/0255-0857.108715  PMID:23508426
Purpose: Damage caused by an organism during infection is attributed to production of virulence factors. Different virulence factors produced by the organism contribute to its pathogenicity, individually. During infectious conditions, role of virulence factors produced by the pathogen is different, depending upon the site of involvement. Pseudomonas aeruginosa is an opportunistic nosocomial pathogen known to cause infections of the respiratory tract, burn wound, urinary tract and eye. Importance of virulence factors produced by P. Aeruginosa during infections such as keratitis, burn wound and respiratory tract is known. The present study was designed to understand the importance of different virulence factors of P. aeruginosa in urinary tract infection in vivo. Materials and methods: An ascending urinary tract infection model was established in mice using standard parent strain PAO1 and its isogenic mutant, JP2. Mice were sacrificed at different time intervals and renal tissue homogenates were used for estimation of renal bacterial load and virulence factors. Results: Both parent and mutant strains were able to reach the renal tissue. PAO 1 PAO1was isolated from renal tissue till day 5 post-infection. However, the mutant strain was unable to colonise the renal tissue. Failure of mutant strain to colonise was attributed to its inability to produce protease, elastase and rhamnolipid. Conclusion: This study suggests that protease, elastase and rhamnolipid contribute to pathogenesis and survival of P. aeruginosa during urinary tract infection.
  2 3,727 368
CASE REPORTS
First case report of acute hemorrhagic leukoencephalitis following Plasmodium vivax infection
V Venugopal, M Haider
January-March 2013, 31(1):79-81
DOI:10.4103/0255-0857.108736  PMID:23508437
Acute hemorrhagic leukoencephalitis (AHLE, Hurst's disease) is a rare hyperacute variant of acute disseminated encephalomyelitis (ADEM) characterized by severe, rapidly progressive clinical illness and hemorrhagic necrosis of white matter. Like ADEM, it is often preceded by viral illness or vaccination. Plasmodium vivax infection is usually uncomplicated and non-fatal with only a handful of reports of central nervous system complications. In this article, we report a previously unknown association between AHLE and P. vivax infection.
  1 4,643 174
Dipylidium caninum infection in a child: A rare case report
MV Narasimham, P Panda, I Mohanty, S Sahu, S Padhi, M Dash
January-March 2013, 31(1):82-84
DOI:10.4103/0255-0857.108738  PMID:23508438
Dipylidiasis is a zoonotic parasitic infestation caused by the dog tapeworm Dipylidium caninum. Human dipylidiasis has been rarely reported in English literature. Young children are mostly at risk of acquiring the infection due to their close association with dogs and cats. We report a rare case of Dipylidium caninum infection in a 4 year old male child. The diagnosis was based on microscopic examination of stool. Confirmation of the proglottid segments was done by histopathological examination. To the best of our knowledge this is the first human case of Dipylidium caninum reported from this part of the country.
  1 9,107 160
Primary meningococcal arthritis of sacroiliac joint: A rare case report
S Sahu, I Mohanty, MV Narasimham, S Pasupalak, B Parida
January-March 2013, 31(1):87-89
DOI:10.4103/0255-0857.108743  PMID:23508440
Infection of the sacroiliac joint is a rare entity. Clinical signs and symptoms are usually nonspecific and result in delayed diagnosis. We report a rare case of primary meningococcal arthritis of right sacroiliac joint in an 11-year-old male child. Synovial fluid aspirated from the joint space showed Gram-negative diplococci which were confirmed as Neisseria meningitidis by culture and necessary biochemical tests followed by serogrouping by using polyvalent antisera. He was treated successfully with antibiotics.
  1 2,247 110
CORRESPONDENCE
Microfilaruria with intermittent chyluria in pregnancy: An unusual association
M Pujani, S Agarwal, A Jain
January-March 2013, 31(1):100-101
DOI:10.4103/0255-0857.108761  PMID:23508449
  1 1,748 96
BRIEF COMMUNICATIONS
Detection and characterisation of rotaviruses from children less than 5 years hospitalised with acute gastroenteritis in Nagercoil
S Babji, R Arumugam, A Peters, S Ramani, G Kang
January-March 2013, 31(1):69-71
DOI:10.4103/0255-0857.108727  PMID:23508433
Group A rotavirus continues to be the major cause of severe gastroenteritis in young children in developing countries. In this study, we report the prevalence and genotype of rotaviruses identified from children <5 years of age hospitalised with acute gastroenteritis from Nagercoil, Tamil Nadu from 2007-2010. From the 139 children included in the study, 71 samples (51%) were positive by ELISA and 65 samples were positive by PCR-based methods. G1P[8] (44.6%) was the most commonly identified genotype. In addition, we report detection of rotavirus in two of three CSF samples from children with seizures.
  - 2,208 266
CASE REPORTS
Cefotaximase and AmpC-producing Shigella flexneri in case of dysentery from southern India
S Oommen, PM Sivan Pillai, S Sushamabai, P Jose Paul
January-March 2013, 31(1):77-79
DOI:10.4103/0255-0857.108734  PMID:23508436
Diarrhoea and dysentery caused by Shigella spp. are major public health concerns. Emerging multidrug resistance (MDR) in this pathogen further complicates this disease. Extended spectrum β-lactamases (ESBLs) have been described in this pathogen, which significantly compromises the treatment options for shigellosis. The usual ESBLs seen are sulfhydryl variable (SHV)-type; cefotaximases (CTX-M) are very uncommonly detected. Here, we report a CTX-M type and AmpC-producing Shigella flexneri from a three-year-old boy residing in Central Kerala, South India.
  - 2,187 164
Pulmonary hydatid disease with coexistent aspergillosis: An incidental finding
S Agarwal, S Bohara, A Thakran, P Arora, R Singh, PN Agarwal
January-March 2013, 31(1):85-86
DOI:10.4103/0255-0857.108740  PMID:23508439
There are only a few case reports in the literature on the coexistence of aspergillosis and echinococcosis. We report a case of a 45-year-old immunocompetent patient who presented with a history of intermittent fever and cough with haemoptysis. Chest x-ray and CECT showed a large cystic lesion in right lower lobe with multiple floating membranes. Histopathological examination of cyst wall revealed the laminated membrane of hydatid cyst along with infiltration of its wall with septate fungal hyphae with acute angle branching suggestive of aspergillosis.
  - 2,913 127
CORRESPONDENCE
Candidemia caused by amphotericin B and Fluconazole resistant Candida auris
S Sarma, N Kumar, S Sharma, D Govil, T Ali, Y Mehta, A Rattan
January-March 2013, 31(1):90-91
DOI:10.4103/0255-0857.108746  PMID:23508441
  - 3,518 251
Isolation and characterization of the first vancomycin-dependent Enterococcus from India
T Banerjee, S Anupurba
January-March 2013, 31(1):91-92
DOI:10.4103/0255-0857.108747  PMID:23508442
  - 1,629 209
Corrections in molecular characterization of S. aureus
VA Kumar
January-March 2013, 31(1):92-92
DOI:10.4103/0255-0857.108748  PMID:23508443
  - 1,352 117
Iodine-glycerol as an alternative to lactophenol cotton blue for identification of fungal elements in clinical laboratory
R Vignesh, CR Swathirajan, S Solomon, EM Shankar, KG Murugavel, I Paul, G Waldrop, SS Solomon, P Balakrishnan
January-March 2013, 31(1):93-94
DOI:10.4103/0255-0857.108752  PMID:23508444
  - 5,672 218
Breast abscess: Sole manifestation of Salmonella typhi infection
A Banu, MMN Hassan, M Anand
January-March 2013, 31(1):94-95
DOI:10.4103/0255-0857.108753  PMID:23508445
  - 2,299 152
Detection of N. gonorrhoeae and C. trachomatis infection using urine sample from symptomatic high-risk women by APTIMA Combo2 assay
AR Risbud, G Rao, A Das, P Narayanan, P Prabhakar
January-March 2013, 31(1):96-97
DOI:10.4103/0255-0857.108756  PMID:23508446
  - 1,654 137
Evaluation of a commercially available polyvinylidene fluoride membrane filtration system for water decontamination
MR Francis, S Roy, R Sarkar, V Balraj, G Kang
January-March 2013, 31(1):97-98
DOI:10.4103/0255-0857.108758  PMID:23508447
  - 1,832 85
Occupational exposure to Human Immunodeficiency Virus infection: A case missed is a life lost
SA Ganju, S Bhagra, RC Guleria, V Sharma, AK Kanga
January-March 2013, 31(1):98-99
DOI:10.4103/0255-0857.108760  PMID:23508448
  - 1,453 142
EDITORIAL
Challenges to pneumococcal vaccine in India
R Kanungo
January-March 2013, 31(1):1-2
DOI:10.4103/0255-0857.108701  PMID:23508420
  - 7,186 792
ERRATUM
Erratum

January-March 2013, 31(1):104-104
PMID:23508450
  - 753 65
ORIGINAL ARTICLES
Alteration in sample preparation to increase the yield of multiplex Polymerase Chain Reaction assay for diagnosis of genital ulcer disease
G Rao, A Das, P Prabhakar, V Nema, AR Risbud
January-March 2013, 31(1):15-18
DOI:10.4103/0255-0857.108709  PMID:23508423
Purpose: Genital Ulcer Disease (GUD) is common sexually transmitted infection (STI). Multiple studies have shown that GUDs are strongly associated with the transmission and the acquisition of HIV infection. An accurate diagnosis of common etiology of GUD namely Herpes, syphilis and Chancroid is possible using Multiplex PCR (M-PCR). However, frequent presence of Polymerase Chain Reaction inhibitors in the ulcer swab specimen limits the performance of the assay. In order to overcome this problem, alternative specimen preparation method was used. Materials and Methods: To determine the common etiology, GUD specimens obtained under an STI operations research study were tested with M-PCR after the samples were prepared using Roche Amplicor specimen preparation kit. PCR inhibiting samples were identified from that, which showed negative results. These samples were subjected to phenol-chloroform extraction and ethanol precipitation before the conduct of M-PCR on them. Results: Of the 237 GUD specimens tested, in 145 etiologies could be detected, whereas 92 samples were found negative. Further spiking with one of the target DNA, 128 of the negative samples were found to contain the inhibitors. These 126 samples were then subjected to phenol chloroform extraction and ethanol precipitation followed by M-PCR. Using this method for sample preparation, etiology could be determined in 46 (23%) additional samples. This success rate of altered sample preparation method has been lower than that has reported. Conclusion: The results indicate that sample preparation using phenol chloroform extraction and ethanol precipitation, prior to M-PCR helps to eliminate the inhibitors and increase the yield of the assay. However, being a laborious procedure, it may be used for samples giving negative results after the screening by Roche Amplicor specimen preparation kit.
  - 2,187 161
Evaluation and characterisation of A and B fragments of Corynebacterium diphtheriae toxin towards recombinant diphtheria vaccine
S Abulmagd, M Emara, S Aziz, R El-Domany
January-March 2013, 31(1):3-9
DOI:10.4103/0255-0857.108702  PMID:23508421
Background: Diphtheria is a highly communicable disease caused by toxin-producing strains of Corynebacterium diphtheriae. Objectives: To evaluate the efficacy of A and B subunits of diphtheria toxin (DT-A, DT-B) as potential vaccines against C. diphtheriae. A culture of C. diphtheriae (strain PW 8) was grown on Loeffler plates while Lingood medium was used for production of diphtheria toxin (DT). Materials and Methods: DT was purified and digested to obtain pure DT-A and DT-B and detoxified to obtain diphtheria toxin. Four groups of mice were immunised with different antigens (Ag) of C. diphtheriae. Results: The antibody (Ab) titres were significantly increased with immunised groups subsequent to three injections. On the other hand, Ab titres were estimated after the three immunisations and the levels of different Ab isotypes were comparatively measured. The levels of various isotypes immune responses showed variation between immunised groups where the IgG subclasses were significantly increased mainly with DPT immunised group. The IgM and IgA were significantly increased with DT-A more than others. Additionally, the evaluation of the cellular immune responses demonstrated that spleen cells from DPT and DT-A groups gave highly significant proliferative response with production of high levels of IL-2 and IFN-γ (Th1/Th2). Separation and purification of DT gene were performed using polymerase chain reaction (PCR) and sub-cloned in pGEM-T vector, for further studying of recombinant vaccine. Conclusion: Our results showed the possibility to prepare a potent recombinant vaccine containing whole DT gene or DT-A against C. diphtheriae or could be used in treatment of cancer as it give high levels of IL-2 and IFN-γ.
  - 5,291 464
Multiplex polymerase chain reaction using insertion sequence 6110 (IS6110) and mycobacterial protein fraction from BCG of Rm 0.64 in electrophoresis target genes for diagnosis of tuberculous lymphadenitis
K Sharma, N Gupta, A Sharma, G Singh, PK Gupta, A Rajwanshi, SC Varma, M Sharma
January-March 2013, 31(1):24-28
DOI:10.4103/0255-0857.108714  PMID:23508425
Purpose: Tubercular lymphadenitis (TBLA) is a common manifestations of extrapulmonary tuberculosis (EPTB) accounting for 30-40% of cases. Prompt diagnosis and timely initiation of anti-tubercular therapy (ATT) is the key for successful clinical outcome. This study was carried out to evaluate multiplex polymerase chain reaction (MPCR) using MPB64 and IS6110, and compare with the conventional methods for rapid diagnosis of TBLA. Materials and Methods: In our study, lymph node fine-needle aspirates of patients were evaluated for TBLA. They were classified as Group I: TBLA group, divided into (a) Confirmed TBLA cases (n0 = 80): Culture/smear-positive or cytological examination showing presence of epithelioid cell granuloma with or without multinucleate giant cell and caseation necrosis with presence of AFB, and (b) suspected TBLA cases ( n = 30): Culture/smear-negative and cytological examination showing presence of epithelioid cell granuloma and response to ATT and Group II (Control) (n = 25): Patients of lymphadenopathy confirmed to be caused by other diseases such as sarcoidosis, lymphoma, etc., All samples were subjected to conventional tests and MPCR. For MPCR we used Mycobacterium tuberculosis-specific deoxyribonucleic acid sequences specific for the MPB64 and IS6110 region. Results: In the confirmed TBLA group, Ziehl-Neelsen (ZN) smear, cytology, culture, and MPCR positivity was 30%, 70%, 26.3%, and 91.3% respectively. In the suspected TBLA group, smear and culture were negative, and sensitivity of cytology and MPCR was 73.3% and 86.6%, respectively. In the control group all tests were found to be negative, thus giving a specificity of 100% to all the tests in the study. Conclusion: In conclusion, techniques like MPCR with high sensitivity and specificity can play an important role in rapid diagnosis of TBLA.
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RESEARCH SNIPPETS
Research snippets
P Desikan
January-March 2013, 31(1):102-103
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2004 - Indian Journal of Medical Microbiology
Published by Wolters Kluwer - Medknow

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