International Journal of Molecular and Clinical Microbiology
Volume:1 Issue: 1, Winter and Spring 2011

Meningococcal disease remains a significant global public health and is unique among causes of bacterial meningitis and sepsis where it not only causes sporadic disease but also outbreaks. Meningococcal disease has a rapid onset with high mortality. The understanding of immunopathogenesis is crucial for development of novel therapeutic strategies and vaccines designed against meningococcal disease. In this review, immunological aspects of meningococcal disease have been discussed and the immunopathogenesis of this disease is challenged.

Examples of inter- and intramolecular direct co-functioning of lectins and enzymes are summarized. The data indicate importance of lectin-enzyme relationships in molecular and clinical microbiology and medical biotechnology. Lectin-enzyme relationships have extended prospects in medicine and biotechnology.

Meningitis is an inflammation of the membranes that surround the brain and spinal cord, thereby involving the arachnoid, the pia and the cerebrospinal fluid (CSF). It is divided into viral and bacterial meningitis. For different reasons the diagnosis of bacterial meningitis is very important. The examination of CSF samples may provide information about causative microorganism. The sensivity of Gram-stained specimen of CSF ranges from 60% to 90%. CSF is continuously secreted by the choroids plexus and contains growth factors which are present under specific pathological conditions. As CSF is in close contact with the extracellular space of the brain, biochemical brain modifications could be reflected in the CSF and study of growth factor expression in the CSF might identify biomarkers of meningitis. As fibroblast growth factor-1 (FGF-1) is important in neural cell survival, we studied the changes in the total protein concentration (TPC) and FGF-1 expression in the CSF of normal control and patients with meningitis using Western blott. No significant increase in the CSF TPC in the patients with bacterial meningitis has been seen when compared to control group. However, significant increase in the CSF FGF-1 expression in the patients with meningitis has been seen as compared to control group. It is suggested that FGF-1 could be significantly involved in the pathophysiology of meningitis. we have also conclude that the FGF level in the CSF may provide additional information in the differential diagnosis of meningitis.

The major purpose of this study was isolation, identification and antimicrobial susceptibility of thermophilic Campylobacter spp. from different sources including domestic animals (cow, sheep, horses), poultry, river water and sewage in Tonekabon. Campylobacter spp. was isolated using prêt-KB method and identified by phenotyping tests. Antimicrobial susceptibility of the isolates against different antibiotics and Minimal Inhibitory Concentration (MIC) values were determined by disc diffusion and double dilution methods respectively. In general, 32 strains of thermophilic Campylobacter were isolated from all of the sources. The results obtained indicated that frequency of occurrence of Campylobacter in poultry was high and in sewage was low. In addition, thermophilic Campylobacter isolates were sensitive to Amikacin and Ciprofloxacin and resistant to Ampicillin, Amoxicillin, Penicillin, Amoxiclave and Vancomycin. The lowest values of MIC were found for Ciprofloxacin, while the highest value was found for Streptomycin. Overall, our observations, illustrated that pathogenic Campylobacter were existed in all of the sources in north of Iran. Furthermore, they were sensitive to Amikacin and Ciprofloxacin and resistant to β lactam antibiotics.

Tuberculosis (TB) is one of the most important AIDS associated infectious diseases worldwide. It is a leading cause of illness and death among people with HIV/AIDS in resource-poor areas of the world. The annual incidence of TB among indigenous Iranians stands at 14 cases per 100,000 inhabitants. This study aimed to identify Mycobacterium infection among Iranian HIV positive patients. Two sputum specimens were collected from smear positive AIDS patients. Samples were cultured on Lowenstein-Jensen media for three weeks. DNA was extracted from two samples based on van Embden protocol. To identify Mycobacterium tuberculosis complex, a PCR was conducted to amplify a 245 bp fragment of IS6110 element, followed by RD12 method to confirm PCR result. Whole DNA-RFLP with PvuII restriction enzyme was employed to genotype the cultured isolates. The results obtained by colonial morphology, PCR, and RD12 methods showed that both isolates were belonging to M. tuberculosis, and Genotyping of the isolates by RFLP technique displayed that two isolates were belonging to different strains of M. tuberculosis.

Several reports have indicated that infection with Non-Tuberculosis Mycobacteria (NTM) is increasing worldwide. Therefore, monitoring species causing micobacterial infection in any region is of great importance. This study was going to detect, differentiate, and identify pathogenic mycobacteria in primary clinical samples. Eighty samples collected from tuberculosis suspected patients in Isfahan/Iran were included in this study. The clinical samples were processed for Acid Fast Bacilli (AFB), culture and PCR-PFLP procedures. A 342 bp fragment of rpoB gene was PCR amplified and the products were digested with HindII restriction enzyme to discriminate between tuberculosis and non-tuberculosis mycobacteria. The PCR products were then digested with HaeIII restriction enzyme to identify the species. Of 80 studied samples, 8 showed AFB on microscopy, 9 were cultured positive for mycobacteria, and 32 (40%) were shown positive by PCR. Moreover, 2 specimens were infected with mycobacterium other than tuberculosis. Further digestion with the enzyme HaeIII showed that one of these samples was Mycobacterium leprae and the other one was Mycobacterium kansasii. The results obtained by this study show that similar to many other regions, nontuberclusis mycobaceria infection is increasing in the studied region, although its prevalence in Isfahan is yet lower than the southern parts of Iran.

Gingivitis is an inflammatory destructive disease mainly caused by microbial plaques. Gram-positive and gram-negative bacilli or cocci have been isolated from dental plaque and gingivitis. This study was going to isolate and characterize the pathogenic bacteria from gingival of 100 patients with oral gingivitis. Enriched and specific media used for isolation of bacteria. Identification of isolated bacteria performed via gram staining and biochemical tests. 361 strains comprising 55.98% Streptococci, 2.62% Staphylococcus aureus, 4.22% gram-negative cocci, 26.38% gram-positive bacilli, 0.03% gram-positive filamentous bacteria, 1.3% gram-negative bacilli, 1.3% yeasts, and 1.3% gram-negative filamentous bacteria were isolated. Streptococcus sanguis, Streptococcus mitis, and Streptococcus mutans were the most frequent species among isolated streptococci. The results of present study indicate that a wide range of pathogenic bacteria are responsible for destructions of gingival among Iranian patients. Because of the communication ability of these infections, the diagnosis and treatment of the patients is necessary according to the public health care systems.

Hepatitis C virus (HCV) is a major global health problem and one of the most common causes of chronic liver diseases. The current study was carried out to investigate the ability of High Resolution Melting (HRM) method in HCV genotyping. 40 HCV-Positive sera with unknown and 12 sera with known HCV genotypes were collected from different clinical laboratories in Tehran as well as Rasht in north of Iran. The RT-PCR was performed on RNA extracted from each sample. The first PCR amplification product was used as template for second run in a Nested-PCR followed by HRM method. Unknown genotypes were determined with comparing of their normalized and difference graphs with those obtained by known genotypes as standard. All results were confirmed by direct sequencing. In a comparison between results obtained by HRM method and those of direct sequencing, only 2 out of 40 samples with unclear HCV genotypes had been incorrectly genotyped by HRM method. The results obtained by this study show that HRM can be introduced as a simple, fast, and reliable method for HCV genotyping in clinical laboratories.

Meningitis is one of the most common infectious cerebral nervous system (CNS), defined as an inflammation of the meninges. It is clinically categorized into a chronic and acute based on the acuity of symptoms. Vomiting, bulging fontanel and fever are the main symptoms in the patients with meningitis. Bacterial meningitis is a severe, potentially life-threatening infection that is associated with high rates of morbidity and disability in survivors. The examination of cerebrospinal fluid (CSF) is a keystone in diagnostic procedure for patients with suspected meningitis. CSF contains cytokines and changes in the levels of cytokines have been shown in some neurological diseases. In this study, the total protein contents (TPC) and NGF concentration in the CSF of normal subjects and patients with bacterial meningitis was measured using enzyme linked immunosorbent assay (ELISA). CSF was obtained by lumbar puncture. No significant change in the TPC has been seen between two groups. We have also shown that the concentration of NGF in the CSF of patients with meningitis is higher than in normal control. The data from this study indicate that NGF is a constant component of human CSF. It is also concluded that high concentration of CSF NGF may be partly related to the pathophysiology of meningitis.