Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Khaled Zalata is active.

Publication


Featured researches published by Khaled Zalata.


Toxicology and Applied Pharmacology | 2011

Comparison of imatinib, nilotinib and silymarin in the treatment of carbon tetrachloride-induced hepatic oxidative stress, injury and fibrosis

Mohamed E. Shaker; Khaled Zalata; Wajahat Z. Mehal; Gamal Shiha; Tarek M. Ibrahim

Effective and well-tolerated anti-fibrotic drugs are currently lacking. Therefore, this study was carried out to investigate the potential anti-fibrotic effects of imatinib, nilotinib and silymarin on established hepatic fibrosis in the carbon tetrachloride (CCl(4)) rat model. Male Wistar rats received intraperitoneal injections of CCl(4) twice weekly for 8weeks, as well as daily intraperitoneal treatments of imatinib (10 and 20mg/kg), nilotinib (10 and 20mg/kg) and silymarin (100mg/kg) during the last 4weeks of CCl(4)-intoxication. At the end of the study, hepatic damage was evaluated by analysis of liver function tests and hepatic oxidative stress parameters. Hepatic fibrosis was evaluated by histopathology and morphometry, as well as collagen and 4-hydroxyproline contents. Nilotinib (20mg/kg) was the most effective treatment to counteract CCl(4)-induced hepatic injury as indicated by liver function tests and histopathology. Nilotinib (10mg/kg), nilotinib (20mg/kg) and silymarin (100mg/kg) treatments reduced the mean score of hepatic fibrosis by 31%, 68% and 47%, respectively, and hepatic collagen content by 47%, 49% and 18%, respectively in CCl(4)-treated rats. Hepatic morphometric evaluation and 4-hydroxyproline content revealed that CCl(4)-induced fibrosis was ameliorated significantly by nilotinib (20mg/kg) and imatinib (20mg/kg). Unlike nilotinib, imatinib (20mg/kg) showed some sort of hepatic injury evidenced by elevation of serum aminotransferases and total bilirubin levels, and hepatic total nitrate/nitrite content, as well as characteristic anisonucleosis visualized with the hematoxylin-eosin staining. In conclusion, this study provides the evidence that nilotinib exerts anti-fibrotic activity and suggests that it may be valuable in the treatment of hepatic fibrosis in humans.


Journal of Medical Virology | 2009

Response to pegylated interferon alfa-2a and ribavirin in chronic hepatitis C genotype 4

Hesham El Makhzangy; Gamal Esmat; Mohamed Said; Maissa El-Raziky; Soheir Shouman; Rasha Refai; C. Rekacewicz; Rita R Gad; Nicolas Vignier; Mohamed Abdel-Hamid; Khaled Zalata; Pierre Bedossa; Stanislas Pol; Arnaud Fontanet; Mostafa K. Mohamed

The safety and efficacy of pegylated interferon (PEG‐IFN) alfa‐2a and ribavirin were studied among patients treated for genotype 4 chronic hepatitis C. Ninety‐five patients with chronic hepatitis C genotype 4 were treated with PEG‐IFN alfa‐2a (180 µg/week) plus ribavirin (≥11 mg/kg/day) for 48 weeks. The primary end point was sustained virological response, defined as non‐detectable levels of HCV RNA at the end of follow up (week 72). The proportion with sustained virological response was 58/95 = 61.1% (95% CI = 50.5–70.9%). Side effects were generally mild, well managed by dose reductions (in 62% of patients); in only two patients were side effects sufficiently severe to require treatment interruption. Ninety percent of patients adhered to treatment up to week 12, and their sustained virological response rate was higher compared to non‐adherent (65% vs. 22%, respectively, P = 0.012). None of the patients who failed to achieve 1 log reduction of viral load by week 8 (n = 15), or 2 log reduction by week 12 (n = 17), had a sustained virological response. In conclusion, sustained virological response in genotype 4 Egyptian patients treated with PEG‐IFN alfa‐2a and ribavirin was estimated around 60%, intermediate between sustained virological response observed in genotype 1 and genotype 2–3 patients in Western countries. The early virological response (week 4 or week 8) should be investigated as a criterion to decide whether the patient may benefit from a shorter duration of therapy. J. Med. Virol. 81:1576–1583, 2009.


Liver International | 2008

Predictors of a sustained virological response in patients with genotype 4 chronic hepatitis C

Rita R Gad; Sylvia Males; Hesham El Makhzangy; Soheir Shouman; Aboubakr Hasan; Mohamed Attala; Mostafa El Hoseiny; Khaled Zalata; Mohamed Abdel-Hamid; Arnaud Fontanet; Mostafa K. Mohamed; Gamal Esmat

Objectives: To determine the clinical, biological, virological and histological predictive factors associated with a sustained virological response (SVR) to combined interferon therapy among Egyptian patients infected by genotype 4 hepatitis C virus (HCV).


Journal of Viral Hepatitis | 2012

Role of Helicobacter pylori in patients with HCV-related chronic hepatitis and cirrhosis with or without hepatocellular carcinoma: possible association with disease progression.

Gamal Esmat; Mahmoud El-Bendary; S. Zakarya; M. A. Ela; Khaled Zalata

Summary.  The discovery of Helicobacter hepaticus as a causal agent of hepatitis and hepatocellular carcinoma (HCC) in mice has stimulated interest in looking for Helicobacter species in human liver samples. In this study, we searched for association between H. pylori and HCV‐related liver disease. Liver specimens were collected from eighty‐five patients; they were divided into five different groups according to liver pathology (METAVIR system). Group I (the 1st control group) consisted of 16 patients with chronic hepatitis C without histological activity. Group II consisted of 25 patients with chronic active hepatitis C, Group III, 17 patients with HCV‐related cirrhosis and Group IV, 16 patients with HCV‐related cirrhosis and HCC. Group V (2nd control group) consisted of 11 patients suffering from gastro duodenal and gall bladder diseases but negative for HCV. All cases were tested by polymerase chain reaction on liver samples for the presence of H. pylori DNA Cag A gene. Routine biochemical, radiological and RT‐PCR for HCV RNA were also performed for all cases. The positivity of H. pylori PCR CagA gene in liver tissue was directly proportional to the severity of liver pathology, this being 75%, 52.9% and 32% in groups IV, III and II, respectively, which was more significant than the 1st and 2nd control groups (P < 0.001). There was a significant difference between H. pylori PCR values when compared to METAVIR staging (F) in different groups (P = 0.001). Helicobacter pylori PCR (Cag A gene) was positive in about 28.2% cases of late fibrosis (F3 + F4) while positivity was (5.9%) in early fibrosis (F1 + F2) (P = 0.0001). There was significant difference between H. pylori PCR (Cag A gene) in liver tissue and METAVIR activity in different groups (P = 0.002) as most of H. pylori PCR–positive cases were METAVIR activity A1 and A2 (15.3% and 12.9%, respectively). There was no association between H. pylori PCR and quantitative HCV RNA (P = 0.531). Also there was no significant difference of Child‐Pugh staging in the H. pylori PCR–positive group when compared to the negative group (P = 0.996). There may be an association between the presence of H. pylori (Cag A gene) in the liver and disease progression in HCV‐related chronic hepatitis and cirrhosis with and without HCC.


Pathology Research and Practice | 2012

Molecular subtypes of breast carcinoma in Egyptian women: clinicopathological features.

Amira Kamal El-Hawary; Ahmed Abbas; Ahmed K. A. El-Sayed; Khaled Zalata

Breast carcinoma may be classified into distinct molecular subtypes based on immunohistochemical markers for estrogen, progesterone and Her-2/neu receptors. The aim of the study was to identify the clinicopathological features of the molecular subtypes of breast carcinoma in our locality. A total of 274 surgically resected breast carcinomas were selected from the files of the Dr. KRZ referral pathology laboratory, Mansoura, Egypt, and the Pathology Department of Mansoura University. Molecular subtypes were classified into luminal A, luminal B, Her-2/neu-expressing and triple-negative. Clinicopathological and histological features of molecular subtypes were analyzed. Luminal A subtype was the most prevalent (41.2%), followed by triple-negative subtype (28.5%), then Her2-expressing subtype (19.4%) and luminal B subtype (13.9%). The commonest histological type was infiltrating duct carcinoma (83.2%), followed by infiltrating lobular carcinoma (9.1%) and medullary carcinoma (3.2%). The luminal A subtype was significantly correlated to low tumor grade, lower number of positive lymph nodes metastasis, absence of both necrosis and syncytial growth pattern. We concluded that the commonest molecular subtype of invasive breast carcinoma among Egyptian women is luminal subtype A, which displayed favorable features. Triple-negative subtype and medullary carcinomas are present in a ratio higher than in western countries.


European Journal of Radiology | 2011

Diagnosis and quantification of hepatic fibrosis in children with diffusion weighted MR imaging

Ahmed Abdel Khalek Abdel Razek; Ahmed Abdalla; Eman Omran; Abeer Fathy; Khaled Zalata

PURPOSE To evaluate the accuracy of diffusion weighted MR imaging in diagnosis and quantification of hepatic fibrosis in children with chronic hepatitis. MATERIALS AND METHODS Sixty-three consecutive children (40 boys, 23 girls, median age 9.3 years), with chronic hepatitis and thirty age matched volunteers underwent diffusion weighted MR imaging of the liver using a single shot echoplanar imaging with b-value=0, 250, and 500s/mm(2). Liver biopsy was obtained with calculation of METAVIR score. The ADC value of the liver was correlated with METAVIR score. Receiver operating characteristic curve was done for diagnosis and grading of hepatic fibrosis. RESULTS There was statistical difference in the mean ADC value between volunteers and patients with hepatic fibrosis (P=0.001) and in patients with different grades of METAVIR scores (P=0.002). There was correlation between the mean ADC value and METAVIR score (r=0.807, P=0.001). The cut off point to predict fibrosis (1.7×10(-3)mm(2)/s) revealed 83% accuracy, 85% sensitivity, 82% specificity, 83% PPV, and 85% NPV. The area under the curve was 0.91 for F1, 0.85 for F2, 0.86 for F3 and 0.90 for F4. CONCLUSION The apparent diffusion coefficient value is a promising quantitative parameter used for diagnosis and quantification of hepatic fibrosis in children with chronic hepatitis.


Diagnostic Pathology | 2011

An inexpensive method of small paraffin tissue microarrays using mechanical pencil tips

Abdelhadi M. Shebl; Khaled Zalata; Maha M Amin; Amira Kamal El-Hawary

BackgroundTissue microarray technology has provided a high throughput means of evaluating potential biomarkers in archival pathological specimens. This study was carried out in order to produce tissue microarray blocks using mechanical pencil tips without high cost.MethodConventional mechanical pencil tips (Rotring Tikky II Mechanical Pencil 1.0 mm) were used to cut out 1 mm wax cylinders from the recipient block, creating from 36 to 72 holes. Three cores of tumor areas were punched out manually by using the mechanical pencil tips from donor paraffin embedded tissue blocks and transferred to the holes of the paraffin tissue microarrays.ResultsThis technique was easy and caused little damage to the donor blocks. We successfully performed H&E slides and immunodetection without substantial tissue cylinder loss.ConclusionOur mechanical pencil tip technique is the most inexpensive easy technique among the literature. It also takes a reasonable amount of time and reduces antibody consumption during immunohistochemistry


Clinical and Experimental Pharmacology and Physiology | 2014

Tracking anti‐fibrotic pathways of nilotinib and imatinib in experimentally induced liver fibrosis: An insight

Gamal Shiha; Nashwa Abu-Elsaad; Khaled Zalata; Tarek M. Ibrahim

The tyrosine kinase inhibitors imatinib and nilotinib have been suggested to have promising antifibrotic activity in experimental models of liver fibrosis. The aim of the present study was to investigate new pathways underlying this beneficial effect. Hepatic injury was induced in male Wistar rats by intraperitoneal injection of CCl4 for 12 weeks. During the last 8 weeks of treatment, rats were also injected daily intraperitoneally with 20 mg/kg imatinib or 20, 10 or 5 mg/kg nilotinib. At the end of treatment, effects on fibrosis were assessed by measuring serum fibrotic markers and profibrogenic cytokines, as well as by histopathological examination. Possible anti‐inflammatory effects were estimated by measuring levels of inflammatory cytokines in liver tissue. Liver expression of α‐smooth muscle actin, transforming growth factor (TGF)‐β1 antibodies and platelet‐derived growth factor receptor β (PDGFRβ) was evaluated by immunohistochemical staining techniques. Nilotinib (5 and 10 mg/kg) significantly (P < 0.05) decreased all serum fibrotic markers measured, but 20 mg/kg of either nilotinib or imatinib had limited effects. At all doses tested, nilotinib significantly (P < 0.05) decreased the CCl4‐induced increases in tissue inflammatory cytokines. Furthermore, 5 and 10 mg/kg nilotinib significantly decreased TGF‐β1 levels and tissue expression of its antibody, as well expression of PDGFRβ. In conclusion, low doses (5 and 10 but not 20 mg/kg) of nilotinib, rather than imatinib, can control hepatic fibrosis by regulating levels of proinflammatory cytokines, primarily interleukin (IL)‐1 and IL‐6. Nilotinib also controls the signalling pathways of profibrogenic cytokines by lowering TGF‐β1 levels and decreasing expression of PDGFRβ.


Analytical Cellular Pathology | 2005

p53, Bcl-2 and C-Myc Expressions in Colorectal Carcinoma Associated with Schistosomiasis in Egypt

Khaled Zalata; Wesam A. Nasif; Si-Chun Ming; Mahmoud Lotfy; Nadia Nada; Nabil Gad El-Hak; Stephen H. Leech

Background and Aims: Oncogenes and tumor suppressor genes expression are well described in bladder cancer associated with schistosomiasis especially in Egypt. Scarce studies were directed to colorectal cancer (CRC) associated with Schistosoma mansoni (S. mansoni). Apoptosis (programmed cell death) and the genes regulating this process (e.g., Bcl-2) have recently become a focus of interest in the study of cancer development and progression. In the present study, we aimed to investigate the expression pattern of p53, Bcl-2 and C-Myc in CRC tissues obtained from Egyptian colorectal cancer patients divided in two different groups, one associated with Schistosoma mansoni (CRC-Sm) and the other without Schistosoma mansoni (CRC-NSm). Methods: Seventy-five CRC tumors containing 36 draining lymph node metastatic tumors were immunohistochemically stained using specific monoclonal antibodies for p53, Bcl-2 and C-Myc, in addition the apoptotic activity of these tumors were analyzed. Results and Conclusions: Regardless of the S. mansoni infection, the obtained Results showed that the apoptotic activity was more evident in p53 diffuse positive tumors (P=0.021). There was a significant correlation between p53 diffuse positive staining and Bcl-2 positive immunostaining (P=0.011). Signet ring cell carcinoma and mucinous adenocarcinoma exhibited both intense C-Myc expression than non-mucinous carcinoma (P=0.001). When adjusting for S. mansoni infection, 58.3% of CRC-Sm cases were Bcl-2 positive compared to only (33.3%) of CRC-NSm (P=0.046). Apoptotic activity was more evident in the latter group than of CRC-Sm tumors (P=0.009). p53 and C-Myc expressions were found insignificantly different in CRC-Sm compared with CRC-NSm (P>0.05). These observations suggest that the genotoxic agents produced endogenously through the course of schistosomiasis mansoni may play a role in CRC-Sm pathogenesis through the dysregulation of apoptosis by alteration the expression pattern of Bcl-2 protein differently from CRC-NSm suggesting a different biological behavior.


Cytokine | 2013

CXCL10 antagonism and plasma sDPPIV correlate with increasing liver disease in chronic HCV genotype 4 infected patients

Dina Ragab; Melissa E. Laird; Darragh Duffy; Armanda Casrouge; Rasha Mamdouh; Amal Abass; Dina El. Shenawy; Abdelhadi M. Shebl; Wagdi Elkashef; Khaled Zalata; Mostafa Kamal; Gamal Esmat; Philippe Bonnard; Arnaud Fontanet; Mona Rafik; Matthew L. Albert

Egypt has the highest prevalence of hepatitis C virus infection worldwide. CXCL10 is a potent chemoattractant that directs effector lymphocytes to sites of inflammation. It has been reported that plasma CXCL10 is processed by dipeptidylpeptidase IV (DPPIV) thus leading to the generation of an antagonist form. Using Luminex-based immunoassays we determined the concentration of different forms of CXCL10 (total, agonist, and antagonist). We also evaluated plasma soluble DPPIV (sDPPIV) concentration and plasma dipeptidylpeptidase (DPP) activity. Using flow cytometry and immunohistochemistry, we analyzed the distribution of lymphocyte subsets. Plasma CXCL10 was elevated in chronic HCV patients, however the agonist form was undetectable. Increased sDPPIV concentration and DPP activity supported the NH2-truncation of CXCL10. Finally, we demonstrated an increased frequency of CXCR3(+) cells in the peripheral blood, and low numbers of CXCR3(+) cells within the lobular regions of the liver. These findings generalize the observation of chemokine antagonism as a mechanism of immune modulation in chronic HCV patients and may help guide the use of new therapeutic immune modulators.

Collaboration


Dive into the Khaled Zalata's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge