HARD TICKS (ACARI: IXODIDAE) INFESTING ARABIAN CAMELS (CAMELUS DROMEDARIUS) IN MEDINA AND QASSIM, SAUDI ARABIA.

Ixodid ticks are hematophagous obligatory ectoparasites that occur worldwide and transmit pathogens to humans and other vertebrates, causing economic livestock losses. The Arabian camel (Camelus dromedarius Linnaeus, 1758) is an important livestock animal in Saudi Arabia that is vulnerable to parasitism by ticks. The diversity and intensity of ticks on Arabian camels in certain localities in the Medina and Qassim regions of Saudi Arabia were determined. One hundred forty camels were examined for ticks, and 106 were infested (98 females, 8 males). A total of 452 ixodid ticks (267 males, 185 females) were collected from the infested Arabian camels. The tick infestation prevalence was 83.1% and 36.4% in female and male camels, respectively (female camels harbored significantly more ticks than did male camels). The recorded tick species were Hyalomma dromedarii Koch, 1844 (84.5%); Hyalomma truncatum Koch, 1844 (11.1%); Hyalomma impeltatum Schulze and Schlottke, 1929 (4.2%); and Hyalomma scupense Schulze, 1919 (0.22%). Hyalomma dromedarii was the predominant tick species in most regions, with a mean intensity of 2.15 ± 0.29 ticks/camel (2.5 ± 0.53 male ticks/camel, 1.8 ± 0.21 female ticks/camel). The proportion of male ticks was higher than that of female ticks (59.1 vs. 40.9%). To the best of our knowledge, this is the first survey of ixodid ticks on Arabian camels in Medina and Qassim, Saudi Arabia.

Ectoparasites and Intestinal Helminths of Pigeons in Medina, Saudi Arabia.

The prevalence of ectoparasites and intestinal helminths of different pigeon taxa in Medina, Saudi Arabia, with special emphasis on the feral pigeon, Columba livia domestica (Columbiformes: Columbidae), was evaluated. Fifty-four pigeons were examined externally for ectoparasites and 28 feral pigeons were examined for helminths. Two ectoparasites were recorded on feral C. l. domestica (Harami) pigeons, including the shaft louse Menopon gallinae (Phthiraptera: Menoponidae), and the pigeon fly, Pseudolynchia canariensis (Diptera: Hippoboscidae), with 100 and 88.90% prevalence, respectively. Ectoparasites were also collected from 5 other breeds of C. l. domestica (Pakistani, Farensi, Turki, Kori, and Qatifi). Menopon gallinae infected Pakistani, Farensi, and Turki pigeons with 100% prevalence. A third ectoparasite, the brown poultry louse, Goniodes dissimilis (Psocodea: Philopteridae), infected Farensi, Turki, and Kori pigeons at rates of 100, 50, and 50%, respectively. Qatifi pigeons were not infected with any ectoparasites. Two types of intestinal helminths were recovered from feral pigeons: cestodes of Raillietina spp. (Cyclophyllidea: Davaineidae) and nematodes of Ascaridia sp. (Ascaridida: Ascaridiidae) (with 10.71 and 3.57% prevalences, respectively). To the best of our knowledge, this is the first study to shed light on the parasites of pigeons in Medina, Saudi Arabia.

Schistosoma mansoni: Antiparasitic effects of orally administered Nigella sativa oil and/or Chroococcus turgidus extract.

Schistosoma mansoni is one of the parasites causing schistosomiasis, a disease which threatens millions of people all over the world. Traditional chemical drugs are not fully effective against schistosomaisis due to the evolving drug resistant worm strains, so exploring new remedies derived from natural products is a good way to fight schistosomiasis. In the present investigation two natural products, Nigella sativa oil and Chroococcus turgidus extract were used separately or in a combination to explore their effect on S. mansoni. The infected mice treated with Chroococcus turgidus extract or/and sativa seed oil showed a significant decrease in the total worm burden. The total number of deposited eggs by females of S. mansoni was significantly decreased in the liver of mice treated with Chroococcus turgidus extract or/and sativa seed oil. However, in the intestine, the number of eggs was significantly reduced in mice treated with algal extract and those treated with both algal extract and oil. Fecundity of female S. mansoni showed a significant decrease from mice treated with algal extract or/and sativa seed oil. According to SEM investigations the tegmental surface, oral and ventral suckers of worms also showed considerable changes; as the tubercles lost their spines, some are swollen and torn out. The suckers become edematous and enlarged while the tegmental surface is damaged due to the treatment with Chroococcus turgidus extract or/and sativa seed oil. In conclusion, the Nigella sativa oil and Chroococcus turgidus extract are promising natural compounds that can be used in fighting schistosomiasis.

A new species of Oochoristica (Eucestoda: Cyclophyllidea) parasite of Agama mutabilis (Reptilia: Agamidae) from Egypt.

The morphological and morphometric characterization of Oochoristica mutabili, an anoplocephalid cestode infecting the small intestine of the Egyptian changeable lizard, Agama mutabilis (F: Agamidae) in South Sinai were described by light and scanning electron microscopy as a first description from this host in Egypt. Ten out of fifty six (17.9%) of the examined specimens were infected with Oochoristica. Strobila was 14.6 (11.5-22.3) mm long; composed of 34 (30-45) proglottids; 7 (6-11) undifferentiated, 8 (6-10) contained sexual primordia, 14 (13-20) mature and 5 (3-9) gravid. Scolex 324 (300-360) microm wide with four circular suckers measuring 100 (97-124) microm in diameter; neck region is evident. Genital pores irregularly alternating, situated in the anterior quarter of proglottid; testes in median mass situated in the posterior half of proglottid extending laterally to vitellarium; ovary bilobed and situated in the centre of proglottid, vitellaria entire, slightly wider than one lobe of the ovary. Gravid proglottids contained in a uterine capsule containing numerous oncospheres. The described parasite is compared with different species of the same genus from different hosts, it was found that morphometrically the present species was more or less different from the comparable species and the only morphologically similar species was O. parvovaria. Both species were similar in the presence of the cirrus sac, which lied anterior to the ovary, and the bilobed ovary situated in the center of proglottids. However, it can be differentiated by possessing more proglottids, fewer testes, and the lack of primordial development in immature proglottids of the comparable species.

Variation in apoptosis mechanisms employed by malaria parasites: the roles of inducers, dose dependence and parasite stages.

BACKGROUND: Plasmodium berghei ookinetes exhibit an apoptotic phenotype when developing within the mosquito midgut lumen or when cultured in vitro. Markers of apoptosis increase when they are exposed to nitric oxide or reactive oxygen species but high concentrations of hydrogen peroxide cause death without observable signs of apoptosis. Chloroquine and other drugs have been used to induce apoptosis in erythrocytic stages of Plasmodium falciparum and to formulate a putative pathway involving cysteine protease activation and mitochondrial membrane permeabilization; initiated, at least in the case of chloroquine, after its accumulation in the digestive vacuole causes leakage of the vacuole contents. The lack of a digestive vacuole in ookinetes prompted the investigation of the effect of chloroquine and staurosporine on this stage of the life cycle. Finally, the suggestion that apoptosis may have evolved as a strategy employed by ookinetes to increase the fitness of surviving parasites was explored by determining whether increasing the ecological triggers parasite density and nutrient depletion induced apoptosis. METHODS: Ookinetes were grown in culture then either exposed to hydrogen peroxide, chloroquine or staurosporine, or incubated at different densities and in different media. The proportion of ookinetes displaying positive markers for apoptosis in treated samples was compared with controls and results were analyzed using analysis of variance followed by a Turkey's test, or a Kruskal-Wallis test as appropriate. RESULTS: Hydrogen peroxide below 50 µM triggered apoptosis but cell membranes were rapidly compromised by higher concentrations, and the mode of death could not be defined. Both chloroquine and staurosporine cause a significant increase in ookinetes with condensed chromatin, caspase-like activity and, in the case of chloroquine, phosphatidylserine translocation and DNA fragmentation (not investigated for staurosporine). However, mitochondrial membrane potential remained intact. No relationship between ookinete density and apoptosis was detected but nutrient depletion significantly increased the proportion of ookinetes with chromatin condensation in four hours. CONCLUSIONS: It is proposed that both a mitochondrial and an amitochondrial apoptotic pathway may be involved, dependent upon the trigger that induces apoptosis, and that pathways may differ between erythrocytic stages and ookinetes, or between rodent and human malaria parasites.

Salmonella typhi infection complicated by rhabdomyolysis, pancreatitis and polyneuropathy.

INTRODUCTION: Typhoid is a common infection that can have serious complications. Here we present a severe case of Salmonella typhi infection complicated by rhabdomyolysis and acute kidney injury. CASE REPORT: A 42-year-old male presented with shortness of breath, generalized body aches and upper abdominal pain two weeks after returning from India. Investigations revealed severe metabolic acidosis (arterial blood pH 6.9), high serum creatinine (12.7 mg/dl), hyperuricemia (16.4 mg/dl), hypocalcemia (4.1 mg/dl), hyperphosphatemia (16.1 mg/dl), high serum amylase (1458 u/L), thrombocytopenia (59,000/mm3) and disturbed coagulation profile. The diagnosis of rhabdomyolysis was confirmed by an elevated creatine phosphokinase level of 17,000 U/L. The patient was started on hemodialysis, and two days later he developed broncho-pneumonia and required mechanical ventilation. Blood cultures grew Salmonella typhi; parenteral imipenem-cilastin and ciprofloxacin were initiated. After one week, the patient continued to have fever despite improvement of biochemical parameters and negative blood and stool cultures. Antibiotic drug-fever was suspected and antibiotics were stopped. Subsequently, fever and rash disappeared and the patient was switched to ceftazidime two days later. The patient eventually regained normal kidney function but continued to have weakness in both lower limbs. Electromyography (EMG) and nerve conduction studies revealed diffuse axonal sensorimotor polyneuropathy that progressively improved over time. CONCLUSION: Common infective agents, including salmonella typhi, can present in unusual ways. The possibility of a severe systemic infection being the underlying cause of rhabdomyolysis should not be overlooked. KEYWORDS: Acute Kidney Injury; Neuropathy; Rhabdomyolysis; Salmonellosis; Typhoid.

Human leukocyte antigens as a risk factor for the primary diseases leading to end stage renal disease in Egyptian patients.

The number of patients with end stage renal disease (ESRD) is increasing considerably worldwide. The incidence of ESRD is likely to be higher than that reported from the developed world, with diabetic nephropathy, hypertension and chronic glomerulonephritis being the most common causes in Egypt. The aim of the present study is to investigate the Human leukocyte antigens [HLA-A,-B and -DRB1 antigens] as a risk factor for the primary diseases leading to ESRD in Egyptian patients. Our study included a total of 457 individuals comprising 207 ESRD patients and 250 healthy controls were enrolled into the study. Class I [HLA-A and-B] typing was performed by complement-dependent cytotoxicity (CDC) method, while class II HLA-DRB1 typing was performed by low resolution polymerase chain reaction (PCR)-sequence-specific oligonucleotide probe [PCR-SSOP]. We found that the most common primary disease groups leading to ESRD classified as Diabetic nephropathy, hypertensive nephrosclerosis and chronic glomerulonephritis. HLA-A2, -B8 and DRB1*3 and HLA-DRB1*11 significantly correlated with diabetic nephropathy, respectively. B8-DR3 haplotype is susceptible to DM. In, conclusion, determination of HLA-A,-B and -DRB1 as a risk factor for primary diseases leading to ESRD might be beneficial in preventing progression to ESRD and recurrence of the primary disease post-transplantation.

Naturally occurring triggers that induce apoptosis-like programmed cell death in Plasmodium berghei ookinetes.

Several protozoan parasites have been shown to undergo a form of programmed cell death that exhibits morphological features associated with metazoan apoptosis. These include the rodent malaria parasite, Plasmodium berghei. Malaria zygotes develop in the mosquito midgut lumen, forming motile ookinetes. Up to 50% of these exhibit phenotypic markers of apoptosis; as do those grown in culture. We hypothesised that naturally occurring signals induce many ookinetes to undergo apoptosis before midgut traversal. To determine whether nitric oxide and reactive oxygen species act as such triggers, ookinetes were cultured with donors of these molecules. Exposure to the nitric oxide donor SNP induced a significant increase in ookinetes with condensed nuclear chromatin, activated caspase-like molecules and translocation of phosphatidylserine that was dose and time related. Results from an assay that detects the potential-dependent accumulation of aggregates of JC-1 in mitochondria suggested that nitric oxide does not operate via loss of mitochondrial membrane potential. L-DOPA (reactive oxygen species donor) also caused apoptosis in a dose and time dependent manner. Removal of white blood cells significantly decreased ookinetes exhibiting a marker of apoptosis in vitro. Inhibition of the activity of nitric oxide synthase in the mosquito midgut epithelium using L-NAME significantly decreased the proportion of apoptotic ookinetes and increased the number of oocysts that developed. Introduction of a nitric oxide donor into the blood meal had no effect on mosquito longevity but did reduce prevalence and intensity of infection. Thus, nitric oxide and reactive oxygen species are triggers of apoptosis in Plasmodium ookinetes. They occur naturally in the mosquito midgut lumen, sourced from infected blood and mosquito tissue. Up regulation of mosquito nitric oxide synthase activity has potential as a transmission blocking strategy.

Prevalence of hyperkalemia among hemodialysis patients in Egypt.

INTRODUCTION: Hyperkalemia is a frequent problem in patients with end stage renal disease (ESRD) on maintenance hemodialysis and is often attributed as a cause of deaths in these patients. The aim of this study was to estimate the prevalence of hyperkalemia among Egyptian hemodialysis patients. PATIENTS AND METHODS: 400 ESRD patients on maintenance hemodialysis were enrolled in the study. They were allowed their usual diets and medications during the study periods. For all patients, history and clinical examinations and serum potassium level was measured three times--pre- and post-1st session and pre-next session--at two successive sessions of hemodialysis. RESULTS: The results of this study showed that the prevalence of hyperkalemia was 41.2%, 6.5%, and 66.9% of pre- and post-dialysis and before the next session of dialysis, respectively. Hyperkalemia significantly correlates with potassium-rich diets, non-compliant patients, two sessions of hemodialysis per week, and constipation in ESRD patients during the study periods. Serum potassium level was significantly higher in anuric ESRD patients than those who had residual renal function, patients using acetate dialysate than those using bicarbonate dialysate, and patients with low blood flow rate than those with higher blood flow rates. There was a non-significant correlation between serum potassium and ACEls, B-blockers, or diabetes. CONCLUSION: Hyperkalemia is a frequent problem in patients with end stage renal disease in Egypt. Hyperkalemia significantly correlates with a potassium-rich diet and inadequate dialysis either by prescription or non-compliance. Thrice weekly bicarbonate dialysis with higher blood pump flow rate had better elimination of potassium.

Effect of recombinant human erythropoietin on insulin resistance in hemodialysis patients.

Insulin resistance is a characteristic feature of uremia. Insulin resistance and concomitant hyperinsulinemia are present irrespective of the type of renal disease. Treatment with recombinant human erythropoietin (rHuEPO) was said to be associated with improvement in insulin sensitivity in uremic patients. The aim of this study was to compare insulin resistance in adult uremic hemodialysis (HD) patients including diabetic patients treated with or without rHuEPO. A total of 59 HD patients were studied, patients were divided into 2 groups of subjects: 30 HD patients on regular rHuEPO treatment (group A), and 29 HD patients not receiving rHuEPO (group B) diabetic patients were not excluded. Full medical history and clinical examination, hematological parameters, lipid profile, serum albumin, parathyroid horomone, Kt/V, fasting glucose, and insulin levels were measured in all subjects. Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) was used to compare insulin resistance. The results of this study showed that the mean insulin level of HD patients treated with rHuEPO (group A) (17.5 +/- 10.6 microU/mL) was significantly lower than patients without rHuEPO (group B) (28.8 +/- 7.7 microU/mL), (P<0.001). Homeostasis Model Assessment of Insulin Resistance levels in group A were significantly lower than in group B (3.8 +/- 2.97, 7.98 +/- 4.9, respectively, P<0.001). Insulin resistance reflected by HOMA-IR levels among diabetic patients in group A was significantly lower than among diabetic patients in group B (3.9 +/- 3.2, 9.4 +/- 7.2, respectively, P<0.001). Also, HOMA-IR levels among nondiabetic patients in group A were significantly lower than among nondiabetic patients in group B (3.7 +/- 2.85, 6.9 +/- 1.43, respectively, P<0.01). We found a statistically significant negative correlation between duration of erythropoietin treatment, fasting blood glucose, insulin levels, and insulin resistance (r=-0.62, -0.71, and -0.57, P<0.001). Patients treated with rHuEPO showed less insulin resistance compared with patients not treated with rHuEPO in diabetic and nondiabetic patients and, duration of erythropoietin treatment is negatively correlated with insulin levels and insulin resistance in HD patients.