J Egypt Soc Parasitol. 2007 Apr ;37 (1):143-50
17580574 (P,S,G,E,B)
Detection of Entamoeba histolytica/dispar in stool specimens by
using enzyme-linked immunosorbent assay in the population of
Jeddah City, Saudi Arabia.
Abdulaziz B M Barnawi, Abulkader M Tonkal, Mahmoud A H Fouad, Faten A AlBraiken
Department of Medical Parasitology, Faculty of Medicine, King Abdul-Aziz University, Kingdom
of Saudi Arabia.
This study determined the prevalence of intestinal parasites, particularly pathogenic
Entamoeba sp.(E. histolytica), in patients attending three hospitals in Jeddah City, King
Abdulaziz University Hospital, King Abdulaziz Hospital and King Fahad Hospital for
gastro-intestinal troubles. 186 stool specimens were examined microscopically for
parasites and by ELISA kit (E. histolytica II) for true E. histolytica. 83 samples (44.6%)
were positive by microscopy for at least one parasite. Of which, 23 (12.4%) showed two
parasites and 15 (8.1%) three parasites. Eight different parasite species were
identified. The most prevalent were E. histolytica/dispar (n = 26, 31.3%) and Giardia
lamblia (n = 13, 15.7%). Others were Blastocytosis hominis (n = 12, 14.5%),
Entamoeba coli (n = 11, 13.3%), Trichuris trichuria (n = 8, 9.6%), Endolymax nana (n =
6, 7.2%), Hymenolepes nana (n = 4, 4.8%) and Chilomastix mesnili (n = 3, 3.6%). Only
five stool samples (19%) from those identified by microscopy to contain E.
histolytica/dispar, were E. histolytica positive by E. histolytica II ELISA. For the first time
to the authors' knowledge the true prevalence of E. histolytica in Saudi Arabia was
2.7%. E. histolytica II ELISA proved to be a highly useful technique to differentiate
pathogenic E. histolytica from non pathogenic E. dispar.
J Egypt Soc Parasitol. 2006 Dec ;36 (3):737-48
17153692 (P,S,G,E,B)
Detection of malaria in Saudi Arabia by real-time PCR
Manal B Jamjoom, Esam A Azhar, Abdul-Kader M Tonkol, Saeed A Al-Harthi,
Ibrahim M Ashankyty
Department of Medical Parisitology, Faculty of Medicine, King Abdulaziz University, Jeddah,
Saudi Arabia. mjamjoom@kau.edu.sa
Malaria transmission occurs in Saudi Arabia and mainly endemic in the lowlands of Asir
region, the Southwester Province. Imported cases have been reported. Sensitive
routine laboratory techniques for rapid and accurate malaria diagnosis are therefore
desirable to facilitate the identification of individuals infected with the malarial parasites
and to follow up the progress of treatment of such cases with appropriate drugs.
Traditional diagnosis, based on the microscopic examination of Giemsa-stained thick
and thin films remains the main standard method of diagnosis used for malaria
diagnosis in Saudi Arabia. Molecular diagnostic techniques based on the detection of
nucleic acids (as PCR; Real-time PCR) are now highly considered. Real time-PCR a
new methodology has been recently applied to detect human malaria. In this study a
total of forty four samples, using whole-blood, dried blood and thick smears were
examined by PCR and Real-time PCR. Both techniques showed a higher sensitivity
than the microscopy. Parasites were detected in twenty nine samples out of forty four,
compared to twenty six of thirty nine were positive with thin blood film. The real-time
PCR assay offers a practical and positive alternative for rapid and accurate diagnosis
for malaria infection. The application of such technique will be significantly valuable
especially for screening for malaria infection in endemic areas.
J Egypt Soc Parasitol. 2005 Apr ;35 (1):167-80
15881004 (P,S,G,E,B)
Early post-treatment immunoglobulin profile in human
schistosomiasis.
Amany A Abd El-Aal, Maha H El-Arousy, Asma'a M El-Gendy, Abdel-Kader Tunkul,
Soheir A Ismail, Ayman A El-Badry
Department of Parasitology, Faculty of Medicine, Cairo University, Cairo, Egypt.
In a trial at determining the most relevant immunoglobulin isotype that could reflect
success of praziquantel treatment, an ELISA using soluble egg antigen (SEA) was
applied on sera of Egyptian patients suffering from active intestinal schistosemiasis
without hepatic complications, determining the levels of IgE, IgA, IgM, IgG1, IgG2, IgG3
and IgG4 raised against the SEA, both, pre- and early post-treatment. The positive
results obtained to all anti-SEA immunoglobulin isotypes before treatment support the
usefulness of this technique in the diagnosis of schistosomiasis. Except for IgG3
subclass, a statistically significant correlation was found between egg output-reflecting
intensity of infection- and the different immunoglobulin levels, especially anti-SEA IgG4.
When repeating the assay 5-6 months after treatment, the immunoglobulin levels
showed either a rise (in case of IgE) or a drop (in case of IgA, IgM & IgG1-4), all of
statistical significance, yet, IgG1-4 were still positive. So, ELISA could not give a
definite indication of cure after anti-bilharzial treatment. IgE, IgG2 and IgG4 were
revealed to be the most significant immunoglobulin isotypes at the post-treatment level,
both statistically and due to their implications on resistance/ susceptibility to re-infection
and also due to the correlation of IgG4 with the tendency to develop periportal fibrosis.
Conclusively, although not having defined a particular Ig isotype as marker for cure, yet
it exposed the urge for early post-treatment determination of IgE and IgG4 isotypes,
which could serve as markers for picking up high risk patients susceptible to reinfection
or liable to develop bilharzial periportal fibrosis, and who might benefit from a second
course of specific treatment.
J. of Al-Azhar Medical Faculty (Girls), Vol. 26, No. 1,(January) 2005,
ISSN 1110-2381
"Preliminary Study on the Effect of Ziziphus spina Christi.
On Selected Leishmania spp.",
A. M. Tonkal, H. S. Salem, M. B. Jamjoom, A. M. Altaieb and H. A. Al-Bar,
Preliminary Study on the Effect of Ziziphus spina Christi. On Selected
Leishmania spp
‫دراسة أولية عن تأثير نبات السدر على بعض طفيليات الليشمانيا‬
Document Language : Arabic
Abstract : Please see attache file
Publishing Year : 2005 AH
Added Date : Friday, June 13, 2008
Researchers
A. M. Tonkal Researcher Halbar@kau.edu.sa ‫عبد القادر تنكل‬
M. B. Jamjoom Researcher Halbar@kau.edu.sa ‫منال جمجمو‬
A. M. Altaieb Researcher Halbar@kau.edu.sa ‫ألطاف طيب‬
H. S. Salem Researcher halbar@kau.edu.sa ‫هالة سالم‬
‫كامل البحث المنشور باللغة اإلنجليزية‬Preliminary Study on Zizphus effect.doc doc
‫ كامل البحث المنشور باللغة العربية‬.doc doc ‫دراسة أولية حول تأثير نبات السدر‬
J Egypt Soc Parasitol. 2005 Dec ;35 (3):809-18
16333890 (P,S,G,E,B)
Cell death pattern in cerebellum neurons infected with Toxoplasma
gondii
Samar el-Sagaff, Hala Said Salem, Wafa Nichols, Abdel Kader Tonkel, Najlaa Y A AboZenadah
Department of Anatomy, Faculty of Medicine, King Abdel Aziz University, Jeddah, Saudi Arabia.
There is a demand for studying the role of Toxoplasma gondii in cell death seeking
aiding prevention of the disease. The neuro-pathological changes in the cerebellum
cortex in case of acquired toxoplasmosis had been studied. Adult Balb C mice were
infected by intra peritoneal injection of T. gondii RH strain. Immuno-histochemical
expression of pro apoptotic marker Bax had been applied in parallel with Hematoxylin
and Eosin stain to study the layers of cerebellum cortex. The focal necrosis in the
cerebellum was expressed. Necrosis was explained on the basis of hypoxic ischemia
resulting from existing vasculitis followed the infection. Purkinje cell layer was markedly
affected in the form of disfiguring and focal loss of cells with apoptotic and necrotic
changes. Thinning of both the molecular and internal granular layers was recorded
morphometricly. Morphometric study reveals non significant change in the ratio
between the viable to non viable cells in all cerebellum layers among experimental and
control groups though the Purkinje cell layer was mostly affected. Statistical significant
changes in depth proportion of molecular layer: Internal granular (ML: IGL) layers was
noted in experimental and control group (p= .05). Bax expression was not coexisting
with the result of H & E stained cells. The hypothesis emphasizes that toxoplasmosis
resist apoptosis seeking its benefit, and apoptosis followed toxoplasmosis may be due
to another protein rather than Bax.
Clinical and Experimental Immunology: Volume 137 (1) July 2004 p19-23
Mast cells at the host-pathogen interface: host-protection
versus immune evasion in leishmaniasis
SAHA, B.*; TONKAL, A. M. D. J.†; CROFT, S.†; ROY, S.‡
*National
Centre for Cell Science, Ganeshkhind, Pune, India
‡Indian Institute of Chemical Biology, Kolkata, India
†London School of Hygiene and Tropical Medicine, London, UK
SUMMARY
Infection of a susceptible host with Leishmania, a protozoan parasite, causes the
disease leishmaniasis, which is characterized by neutrophil, eosinophil, macrophage,
lymphocyte and mast cell infiltration into the infected tissue followed by parasite growth.
Although the roles played by other cells in leishmaniasis are known, the role of mast
cells remains to be ascertained. Here, we demonstrate that Leishmania regulates mast
cell infiltration to the site of infection, mast cell production and mast cell function
resulting in differential growth of the parasite in resistant (C57BL/6 or CBA/T6T6) and
susceptible (BALB/c) macrophages. An interleukin-3-dependent augmentation in mast
cell committed progenitors is observed in BALB/c but not in C57BL/6 mice during
Leishmania infection. The mast cell supernatants inhibit IFN-γ-dependent restriction of
Leishmania growth in macrophages in BALB/c mice whereas the reverse phenomenon
occurs in C57BL/6 mice. Our data reveals a different facet of host-pathogen interaction.
Copyright © 2004 Blackwell Publishing Ltd.