Molecular and conventional studies on staphylococcus aureus isolated from milk of subclinical bovine mastitis cases and associated dairy workers

Staphylococcus aureus [S.aureus] is the world over pathogen that causes a variety of infections in man and animals. Detection of S. aureus in collected milk samples from apparently normal animals and comparing their genotypic traits with those isolated from hands of dairy workers. A total of 160 apparently normal quarter foremilk samples, collected from 40 machine milking Friesian lactating cows from Aswan governorate, were cultivated on Baird Parker media. 40 swabs collected from dairy workers' hands or faces were streaked on mannitol salt egg yolk agar [MSEY agar]. Isolated Staphylococcus aureus strains were examined for coagulase slide test, Catalase and DNAase test. Staphylococcus aureus isolated were tested by a two multiplex PCR assays one of them was to detect 16SrRNA gene and coagulase [coa] gene. The second multiplex PCR was to clarify presence of Staphylococcus aureus entertoxins type A [SEA] and B [SEB] in positive coagulase S.aureus. For bovine milk, A prevalence rate of 40.6% and 45.0% of California mastitis test [CMT] and Somatic cell count [SCC] was detected respectively. Whereas, coagulase test was positive in 54.4% and 61.1% of bovine milk and dairy workers in the same sequence. 16Sr-RNA gene was positive in 100% of both bovine milk and dairy workers. But coagulase [Coa] gene was positive in 63.4% and 72.2% of milk and dairy workers respectively. SEA was positive in 21.8% and 38.8% of milk and dairy workers respectively, while SEB was positive in 30.1% and 50% in the same sequence. Testing milk [by CMT, SCC microbial isolation] for detection of subclinical mastitis is an essential part of daily evaluation record of each dairy farm. Detection of Staphylococcus aureus by PCR as well as entertoxins identification was found to be rapid, sensitive and accurate. Special concern should be directed to elucidate the kinetic transfer of Staphylococcus aureus between animals and human. Detection of Staphylococcus aureus entertoxin A and B was found to be easy and rapid by using PCR

Comparison of culture, direct antigen detection and PCR for diagnosis of pneumococcal pneumonia

Pneumonia due to Streptococcus pneumoniae [S.pneumoniae] is a major cause of morbidity and mortality among children and adults worldwide. Comparison of Culture, Direct Polysaccharide Antigen Detection and Polymerase chain Reaction 'PCR' for diagnosis of Pneumococcal Pneumonia. This study was conducted on 80 nasopharyngeal aspirates from children patients with community acquired pneumonia [CAP], admitted to Cairo university specialized Pediatric hospital [CUSPH]. Only samples of good quality and Significant counts of alpha haemolytic streptococci were subjected to optochin sensitivity, bile solubility test, pneumococcal antigen detection by latex and PCR. Significant counts of alpha haemolytic streptococci were isolated from-35 patients out of the original 80 patients. Out of 35 samples, 11 [31%] were optochin sensitive and bil soluble. Considering the optochin disc sensitivity test as a reference method, both Latex agglutination test and PCR had excellent sensitivity [100%] and good specificity: 62.5% for latex agglutination test and 79% for PCR. Culture and optochin sensitivity remain to be the definitive diagnostic test for streptococcus pneumoniae. Pneumococcal antigen detection by latex is a rapid screening test but should be combined with culture to avoid false positive results. PCR had good sensitivity and specificity, but it is difficult to be used for routine clinical diagnosis because of its relatively high cost and its tedious work that needs skilled personnel

Role of Chlamydia pneumoniae infection in Egyptian asthmatic patients

The role of respiratory infections in asthma is poorly understood. Chlamydia pneumoniae [C.pneumoniae] infection is claimed to be of importance for the development of asthma. This study was designed to investigate the role of Chlamydia pneumoniae infection in asthmatic patients in an attempt to understand its role in respiratory tract allergy. Forty adults and forty children with acute attack of asthma were included in our study in addition to ten healthy adults and ten healthy children as control group. Nasopharyngeal aspirates were taken from patients and controls and tested for the presence of Chlamydia pneumoniae by tissue culture and PCR. Six [15%] adult patients were positive by culture as well as PCR while two [5%] patients were positive by culture alone, in children, four [10%] patients were positive by both culture and PCR, only one [2.5%] patient was positive by culture alone. None of the control group gave positive result with culture or PCR. Taking chlamydia tissue culture as the reference method, the PCR sensitivity in adult group was 75% and in children 80% while the specificity in both groups was 100%. There is no statistically significant difference regarding the chlamydia positivity by culture and PCR between the patient group and the control group suggesting that C.pneumoniae may not play a significant role in the pathogenesis of asthma

Biological significance of stem cells [CD34 +] and vascular endothelial growth factor [VEGF] in the peripheral blood of patients with acute myocardial infarction

Reports on stem cell transplantation-an innovative approach to repair damaged myocardium following acute myocardial infarction [AMI]-have raised the question of a possible spontaneous mobilization of corresponding stem cells from the bone marrow of ischemic patients. Exposed to vascular endothelial-derived growth factor [VEGF], such cells would differentiate into myocardial cells within the infarcting myocardium, thus hopefully initiating the reparative process. The present work assessed the prevalence of marrow derived stem cells expressed in term of percent of CD34 + cells in the peripheral blood of patients sustaining AMI, as well as the serum level of VEGF needed for their differentiation into cardiac myocytes. We studied 21 male patients with AMI [mean age 52.5 +/- 8.9 years]. Myocardial infarction was anterior in 10 and inferior in 11 patients. Eleven healthy males [mean age 53.9 +/- 9.4 years] served as controls. Following admission, all patients and controls were subjected to clinical examination including 12-lead ECG with routine laboratory evaluation comprising total and differential CBC, hepatic and renal functions, as well as relevant cardiac serum enzymes with the latter repeatedly measured every 8 hours to detect the highest peak of CK. Specific laboratory measurements included flowcytometric analysis of peripheral blood mononuclear cells to detect CD34 + population and serum VEGF level by ETA on admission, 3 day, and prior to discharge. Comparing the mean percent values of CD34 + cells on admission [7.02 +/- 3.08], ischemic patients exhibited insignificantly higher levels of CD34 on the 3rd day [8.57 +/- 3.5] as well as on discharge [8.45 +/- 3.5]. The above mentioned values were also insignificantly different from samples withdrawn from control subjects [8.84 +/- 3.4]. However, CD34 cell population was positively correlated with the extent of myocardial damage expressed in terms of peak CK. Thus with an arbitrary limit of >/= 30% rise in CD34, two patients subgroups could be stratified, with 12 patients having >/= 30% rise in CD 34, exhibiting a peak CK of 2498.6 IU/L, and 9 patients showing < 30% rise in CD34 presenting a peak CK of 1312.9 IU/L. However this relationship was not of statistical significance. Serum VEGF surprisingly showed a trend towards decrease rather than increase when compared to control subjects [1.23 +/- 0.99 versus 2.79 +/- 1.67 respectively, p = 0.001], with the decline maintained over the 3rd day and prior to discharge in most patients, raising the issue of increased consumption during the process of stem cell differentiation. Acute myocardial infarction apparently initiated a series of molecular and biological events whereby continued mobilization of bone marrow stem cells [expressed by continuing rise of CD34 marker] was triggered. Subsequent homing into myocardium lead to continuous consumption of VEGF needed for their differentiation into cardiac myocytes. This phenomenon could be part of a spontaneous reparative process potentially raising hopes of therapeutic applications