Publications by authors named "Ragaa R Hamed"

Rhipicephalus (Boophilus) annulatus is a bloodsucking ectoparasite that causes severe production losses in the cattle industry. This study aims to evaluate the in vitro effects of tannic acid, hematin (GST inhibitors) and different plant extracts (rich in tannic acid) on the activity of the recombinant glutathione S-transferase enzyme of the Egyptian cattle tick R. annulatus (rRaGST), in order to confirm their ability to inhibit the parasitic essential detoxification enzyme glutathione S-transferase.

View Article and Find Full Text PDF

Infestation of cattle by ticks of Rhipicephalus spp. results in severe veterinary and economical losses. Identification of novel proteins from tick salivary glands will enhance our understanding of several aspects of tick physiology and will aid in the development of anti-tick vaccines.

View Article and Find Full Text PDF

The control of Rhipicephalus annulatus ticks in Egypt and other countries relies principally on the application of acaricides which have many drawbacks. Recently, cattle vaccination against ticks showed a potential unconventional approach to control ticks. As a target, salivary glands contain various proteins that may play specific roles during attachment, feeding and may modulate the immune system of the host.

View Article and Find Full Text PDF

In order to identify antigens that can help prevent camel tick infestations, three major glycoproteins (GLPs) about 97, 66 and 40 kDa in size were purified from adult and larval Egyptian ticks, Hyalomma (H.) dromedarii, using a single-step purification method with Con-A sepharose. The purified GLPs were evaluated as vaccines against camel tick infestation in rabbits.

View Article and Find Full Text PDF

Down syndrome (DS) is the phenotypic manifestation of trisomy 21. Our study was concerned with the characterization and purification of glutathione S-transferase enzyme (GST) from normal and Down syndrome (DS) erythrocytes to illustrate the difference in the role of this enzyme in the cell. Glutathione S-transferase and glutathione (GSH) was determined in ten DS and ten healthy children matched for age (3-10 years).

View Article and Find Full Text PDF
Article Synopsis
  • Scientists studied a special type of tick called Rhipicephalus annulatus and found a new protein they named Ra-sHSPII by using antibodies from rabbits.
  • This protein can help protect other proteins from getting damaged by heat, acting like a shield.
  • The researchers found that Ra-sHSPII reacts well with different tick proteins, showing it might be useful for understanding how ticks survive and protect themselves.
View Article and Find Full Text PDF
Article Synopsis
  • * The cloned GST gene was expressed in E. coli, purified, and demonstrated high activity on the substrate 1-chloro-2,4-dinitrobenzene (CDNB) with optimal function at pH 7.5, indicating its effectiveness as an enzyme.
  • * Immunoblotting analyzed the presence of GST in various B. annulatus tissues, showing similarities to GSTmu homologues in other tick species, but a lack of detection in Orn
View Article and Find Full Text PDF

The equilibrium unfolding of the major Physa acuta glutathione transferase isoenzyme (P. acuta GST(3)) has been performed using guanidinium chloride (GdmCl), urea, and acid denaturation to investigate the unfolding intermediates. Protein transitions were monitored by intrinsic fluorescence.

View Article and Find Full Text PDF

An intracellular glutathione transferase was purified to homogenity from the fungus, Mucor mucedo, using DEAE-cellulose ion-exchange and glutathione affinity chromatography. Gel filtration chromatography and SDS-PAGE revealed that the purified GST is a homodimer with approximate native and subunit molecular mass of 53 kDa and 23.4 kDa, respectively.

View Article and Find Full Text PDF

A PHP Error was encountered

Severity: Warning

Message: fopen(/var/lib/php/sessions/ci_session5c5b7j374vt1r45qefo3mc76trogcioi): Failed to open stream: No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 177

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)

Filename: Session/Session.php

Line Number: 137

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once