Ultrastructural pathology of the upper respiratory tract of rabbits experimentally infected with Pasteurella multocida A:3

Twenty-four 8 to 9 week-old Pasteurella multocida-free rabbits were divided into three equal groups, the first group was pretreated with hydrocortisone and inoculated intranasally with pasteurella multocida serotype A:3. The second group was inoculated intranasally with P. multocida without hydrocortisone treatment. The third group was inoculated with phosphate buffered saline only and used as a control group. Pasteurella multocida was isolated from the nasal cavity of all infected rabbits in group 1 and 2 and from the trachea of seven rabbits in group 1 and five rabbits in group 2. This study was conducted to observe the ultrastructural changes of the upper respiratory tract of hydrocortisone treated and non-treated rabbits infected with P. multocida serotype A:3. The ultrastructural changes detected in infected rabbits were ciliary destruction and deciliation of the ciliated epithelial cells, cellular swelling, goblet cell hyperplasia and endothelial cell damage. Pasteurella multocida was observed attached to the degenerated cilia,microvilli and mucus. Pasteurella multocida infection was associated with inflammatory responses, which may have caused tissue damage. It is possible that hydrocortisone modulates the severity of infection as an immune suppressor and an inhibitor of goblet cell secretion

Molecular characterization of horseshoe crab anti-lipopolysaccharide factor C-peptide for hybridization-based detection method of gram negative bacteria.

Recent advances in molecular techniques have revolutionized the detection of microorganism. The development of a molecular-based technique for detection of the three different targets of Enterbacteriacae was undertaken. Primer and probe were designed based on specific pepted of novel hemolymph protein of horseshoe crabs (Factor C anti-LPS) Tachypleus tridentatus that is believed to be involved in the binds to the lipopolysaccharide of Escherichia coli, Salmonella and Vibrio cholerae. The aim of our study the exploit part of cell wall polysaccharide in the development of improved detection method based on molecular approaches. In the gene detection assay, Lipopolysaccharide gene of Salmonella, V. cholera and E. coil were hybridized to anti-LPS factor gene found in the biolysate of the marine animals. The wzm and wzt genes encoding O-polysaccharide genes were amplified in these pathogens and the LPS factor C were amplified from the marine lysate. Development of a PCR-based technique for detection of the food-borne pathogens particularly Sa Salmonella, V. cholera and E. coil were achieved. Thus rapid, sensitive and reliable techniques for the detection of food-borne pathogens developed

Detection of diarrheagenic Escherichia coli isolated using molecular approaches.

Escherichia coli strains are among the major bacterial causes of diarrheal illness. There are now seven classes of diarrheagenic E. coli (DEC), namely enteropathogenic E. coli (EPEC), enterohaemorrhagic E. coli (EHEC), enteroinvasive E. coli (EIEC), enterotoxigenic E. coli (ETEC), enteroaggregative E. coli (EAEC), diarrhea-associated hemolytic E. coli (DHEC) and Cytolethal Distending Toxin (CDT)-producing E. coli. Due to the need for costly and labor-intensive diagnostic procedures, identification of DEC is difficult at standard laboratories. Therefore, Polymerase Chain Reaction (PCR) or dot blot has been used for genetic detection of DEC of 25 E. coli isolates from different sources. Amplification of eae (277 bp), bfp (266 bp), stx1 (154 bp), EAST (94 bp), stx2 (698 bp) and elt (450 bp) genes of a single product in separate reactions was produced. PCR showed ability to amplify and detected genes of the most common important categories of diarrheagenic E. coli isolates of different sources, it is possible implementation of this technique to diagnosis water, foodborne outbreaks related to E. coli. Dots blot and sequence analysis used to confirm the results of PCR

Ultrastructural Observation of Nasal and Pulmonary Intracellular Pasteurella multocida A:3 in Rabbits

Sixteen 8- to 9-week-old Pasteurella multocida-free rabbits were divided into two equal groups. Eight rabbits in one group were inoculated intranasally with P. multocida type A:3. The other eight were inoculated intranasally with phosphate-bu¡ered saline and used as controls. Nasal swabs taken before and after inoculation were cultured for bacterial isolation. Post-mortem nasal swabs and lung samples were cultured for bacteriological isolation. Nasal mucosa and lung samples were collected and processed for transmission electron microscopy. Pasteurella multocida was isolated from the nasal cavity of all infected rabbits and from the lungs of four infected rabbits. Degenerative ultrastructural changes in epithelial cells and endothelial cells were seen in the infected rabbits. Deciliation of the cilated epithelium and hyperplasia of the goblet cells in the nasal mucosa were noted. Thickening of the alveolar septa due to hyperplasia of type II pneumocytes, swelling of the endothelial lining of capillaries and in¢ltration of in£ammatory cells were also observed. Intracellular invasion of the nasal epithelial cells and of type II pneumocytes by the organism was observed. Coccobacilli were observed in membrane-bound vacuoles in the cytoplasm of these cells. The vacuoles were adjacent to the host-cell mitochondria and some of these vacuoles appeared to be fused to the mitochondrial membrane. Some type I pneumocytes with intracellular membrane-bound vacuoles containing bacterial cells showed protrusions, which appeared to detach into the alveolar lumina. These results indicated that P. multocida serotype A:3 in rabbits can invade the epithelial cell and cause structural changes in the interstitium, epithelium and endothelium. Heterophils and macrophages appear to play important roles in tissue injury

Molecular characterization of Pasteurella multocida isolates from rabbits

Forty isolates of Pasteurella multocida from healthy (17 isolates) and diseased (23 isolates) rabbits were assayed for the presence of plasmids in seeking to determine whether any correlation exists between the presence of plasmids and health status, sensitivity to antimicrobial agents, capsular and somatic type, and the anatomic site of isolation. Six isolates were found harboring plasmids. A similar ladder pattern ranging from 18 to 3 megadalton (Mda) were found in three isolates recovered from diseased rabbits. One band of molecular weight 6.6 Mda was shared by four of five (4/5) isolates from the diseased rabbits. No correlation was found between the presence of the common plasmids and serotype, resistance to antimicrobial agents, and anatomic sites from which the bacteria were cultured. Random amplification polymorphic DNA was applied to subtype all the isolates of P. multocida. Two single primers were tested for their abilities to generate individual fingerprints by using PCR. Primer 1 grouped the isolates into 7 profiles, and primer 2 grouped them into 15. Random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) results show the presence of a wide heterogeneity within P. multocida isolates. Therefore RAPD-PCR is an efficient technique to detect the DNA polymorphism and could be used to discriminate P. multocida of rabbit isolates together with serologic typing

In vitro antigenicity and cross-reaction of the outer membrane proteins of Pasteurella haemolytica A2, A7 and A9

The outer membrane proteins of Pasteurella haemolytica A2, A7 and A9 were subjected to SDS-PAGE and immunoblotting. The molecular weights of the polypeptide bands ranged between 33 to 97 kDa. The major polypeptide bands for P. haemolytica A2 were 33.4, 39.2 and 45 kDa while the minor polypeptide bands were 50, 58.7, 66.2, 84.7 and 97.4 kDa. Analysis of the outer membrane proteins of P. haemolytica A7 revealed two major protein bands of 33.4 and 45 kDa and three minor polypeptide of 40, 50 and 66.2 kDa. There were three major (33.4, 37.5 and 45 kDa) and one minor protein band (50 kDa) in the outer membrane proteins of P. haemolytica A9. There was one major protein band from each of the P. haemolytica A2, A7 and A9, which was unique to the respective serotype and appeared to represent the respective serotype. These were the 39.2 kDa band for P. haemolytica A2, the 40 kDa band for P. haemolytica A7 and the 37.5 kDa band for P. haemolytica A9. Following homologous immunoblot, all the serotypes showed pronounced antigenicity at the 30 kDa band. Heterologous immunoblot using the antiserum of P. haemolytica A2 did not reveal any antigenic band of P. haemolytica A9 but revealed antigenic bands at 30 and 31 kDa of P. haemolytica A7. Heterologous immunoblot using the antiserum of P. haemolytica A7 revealed antigenic band at 30 kDa of all the three serotypes while the antiserum of P. haemolytica A9 failed to reveal any common antigenic band between all three serotypes. Thus, the 30 kDa band of P. haemolytica A7 may be a suitable candidate for a sub-unit Vaccine against pneumonic pasteurellosis of sheep and goats

The impact of covid-19 lockdown on glycemic control and lifestyle changes in children and adolescent with type 1 diabetes mellitus: a systematic review

Background: The World Health Organization has declared the SARS-CoV-2 outbreak as a pandemic on 11th March 2020. As a measure to prevent the spread of COVID-19, many countries have implemented a lockdown order. The restriction led to lifestyle changes and further affected glycaemic control in children and adolescents with type 1 diabetes mellitus. Thus, this systematic review aims to evaluate the impact of COVID-19 lockdown on glycaemic control and lifestyle changes in children and adolescents with type 1 diabetes mellitus. Method: We systematically identified studies by searching Scopus, Pubmed Central, Oxford Academy, Google Scholar, JSTOR and included 17 studies. Levels of HbA1c, blood glucose readings, time in range (TIR), time below range (TBR), time above range (TAR) and glucose standard deviation (SD) were our primary outcomes. Result: A total of 17 studies are included in our research. Regarding the glycaemic control, n=7 (41 %) studies showed significant improvement in glycaemic outcomes. However, n=3 (18 %) research noticed a deterioration of glycaemic control during the lockdown. Furthermore, there were some studies, n=7 (41%) showed no significant changes. Most of the children and adolescents with type 1 diabetes mellitus had lifestyle changes during this lockdown. It was observed that different countries demonstrate different findings in which studies from Italy and the UK show improvement while studies from KSA, Japan and Egypt show deterioration of glycaemic outcomes. Conclusion: The number of studies that showed children and adolescents with improved glycaemic control is similar to the number of studies that showed no significant changes. Thus, further research on a broader scale is recommended