Decreased serum level of soluble-leptin-receptor in patients with systemic lupus erythematosus.

BACKGROUND: There is some evidence suggesting that leptin and its negative regulator, soluble-leptinreceptor (SLR) may be able to influence inflammatory and autoimmune processes. METHODS: In this study, several variables including socio-demographics, health-related habits, depression score, serum molecules and blood parameters besides the SLR level were evaluated in patients with SLE (SLE-patients) and healthy controls. RESULTS: The patients had significantly lower SLR level and higher depression score than the controls and both of these variables have a significant association with the occurrence of disease in logistic regression model. Moreover, the results of Pearson correlation analysis showed that patients' SLR level was negatively correlated with their weights and BDI scores. CONCLUSION: For the first time, this study indicated a lower level of SLR in SLE-patients and suggested that lower concentrations of SLR in these patients may be implicated in the pathogenesis of SLE.

Strain-specific SCAR markers for the detection of Trichoderma harzianum AS12-2, a biological control agent against Rhizoctonia solani, the causal agent of rice sheath blight.

In order to identify a specific marker for T. harzianum AS12-2, a strain capable of controlling rice sheath blight caused by Rhizoctonia solani, UP-PCR was performed using five universal primers (UP) both separately and in pairwise combinations. The application of two UP primers resulted in the amplification of unique fragments from the genomic DNA of T. harzianum AS12-2, clearly distinguishing it from other Trichoderma strains. The unique fragments had no significant sequence homology with any other known sequence available in databases. Based on the sequences of the unique fragments, 14 oligonucleotide primers were designed. Two primer sets amplified a fragment of expected size from the DNA of strain T. harzianum AS12-2 but not from any other examined strains belonging to T. harzianum, to other Trichoderma species assayed, or to other common fungi present in paddy fields of Mazandaran province, Iran. In conclusion, SCAR (sequence characterized amplified regions) markers were successfully identified and rapid, reliable tools were provided for the detection of an effective biocontrol Trichoderma strain, which can facilitate studies of its population dynamics and establishment after release into the natural environment.

Head and neck squamous cell carcinoma is not associated with interleukin-18 promoter gene polymorphisms: a case-control study.

OBJECTIVE: To investigate the association of two functional single nucleotide polymorphisms in the promoter region of the interleukin-18 gene, at positions -607 and -137, with head and neck squamous cell carcinoma. DESIGN: Genomic deoxyribonucleic acid was extracted, by the salting-out method, from peripheral blood leukocytes. Single nucleotide polymorphisms of the interleukin-18 gene at positions -607 (cytosine/adenine) and -137 (guanine/cytosine) were analysed by sequence-specific polymerase chain reaction. SUBJECTS: One hundred and eleven patients (86 men and 25 women; mean age 56.7+/-13.7 years) and 212 regional controls (165 men and 47 women; mean age 53.3+/-12.2 years) were studied. Control subjects comprised healthy volunteers or cancer-free individuals presenting with otolaryngological disease. The diagnosis of squamous cell carcinoma was confirmed histopathologically. Various clinical parameters were collected at diagnosis, including tumour site, tumour size, lymph node involvement, distant metastasis and stage. RESULTS: There was no significant association between the allele, genotype or haplotype frequencies of the two single nucleotide polymorphisms of the interleukin-18 promoter and the head and neck squamous cell carcinoma susceptibility or clinical parameters at diagnosis. CONCLUSION: Interleukin-18 polymorphisms at positions -607 and -137 did not confer susceptibility to head and neck squamous cell carcinoma in southern Iranian patients.

Promoter polymorphism of transforming growth factor-beta1 gene and ulcerative colitis.

AIM: To elucidate the possible difference in two promoter polymorphisms of the transforming growth factor-beta1 (TGF-beta1) gene (-800G > A, -509C > T) between ulcerative colitis (UC) patients and normal subjects. METHODS: A total of 155 patients with established ulcerative colitis and 139 normal subjects were selected as controls. Two single nucleotide polymorphisms within the promoter region of TGF-beta1 gene (-509C > T and -800G > A) were genotyped using PCR-RFLP. RESULTS: There was a statistically significant difference in genotype and allele frequency distributions between UC patients and controls for the -800G > A polymorphism of the TGF-beta1 gene (P < 0.05). The frequency of the TGF-beta1 gene polymorphism at position -800 showed that the AA genotype and the allele A frequencies significantly differed between the patients and healthy controls (P < 0.05). At position -509, there was no statically significant difference in genotype and allele frequency between the patients and control subjects. CONCLUSION: The results of our study indicate that there is a significant difference in both allele and genotype frequency at position -800G > A of TGF-beta1 gene promoter between Iranian patients with UC and normal subjects.

Association of IL-18 promoter polymorphisms with predisposition to Type 1 diabetes.

AIMS: IL-18, a potent IFN-gamma-inducing cytokine, is capable of polarizing the immune response to a Th1 phenotype. Recent studies have demonstrated an association between single-nucleotide polymorphisms located at positions -607 (A/C) and -137 (C/G) in the promoter region of IL-18 gene and Type 1 diabetes. The aim of the present study was to determine whether the same polymorphisms of the gene were associated with Type 1 diabetes in Iranians. METHODS: In 112 patients with Type 1 diabetes and 194 non-diabetic control subjects, these two single-nucleotide polymorphisms were analysed by sequence-specific PCR. RESULTS: Allele and genotype frequencies of the IL-18 gene polymorphisms were similar in the whole group of Type 1 diabetic patients and controls. However, categorizing patients according to age at onset of diabetes revealed a significant difference in distribution of the genotypes at position -137 between patients with older age at onset (> 15 years) (GG 49%, GC 34%, CC 17%) and control subjects (GG 57.7%, GC 36.6%, CC 5.7%) (P = 0.027). Frequency of the C allele at position -137 was significantly higher in these patients than in controls (P = 0.038). Moreover, there was an association between -607AA/-137CC genotype combination and susceptibility to Type 1 diabetes in this subgroup of patients (pc = 0.027). CONCLUSIONS: The results of this study show that polymorphisms of IL-18 promoter confer susceptibility to Type 1 diabetes in Iranian individuals with onset at older ages. Further investigations are necessary to clarify the effect of IL-18 variants on immune regulation.

Sheath rot of rice in Iran.

Sheath rot of rice occurs in most rice-growing regions of the world. It usually causes yield losses from 20 to 85%. Sheath rot was reported from Iran in 1993. Year after year, the number of diseased plants increased in the Northern Iran. In summer of 2001, these symptoms were observed in most fields: lesions occur on the upper leaf sheaths, especially the flag leaf sheath. As the disease progresses, lesions enlarge and coalesce and may cover most of the leaf sheath. Panicle may fail to completely or at all. Brown or partially brown not filled or partially filled grain is also associated with infection of the panicle. A whitish powdery growth may be found inside affected sheaths. Infected plants were collected and trasferred to laboratory. Small pieces of diseased tissues were washed under tap water for one hour. Then tissues were placed on WA and incubated at 25 degrees C. These isolates were purified and identified as: Sarocladium oryzae, Fusarium udum, F. semitectum, F. avenaceum, F. flocciferum, F. graminearum, Bipolaris oryzae, Alternaria padwickii, Rhizoctonia solani, Paecilomyces sp., Nigrospora sp. and Trichoderma sp. This is the first report of F. udum in Iran. Also this is the first report that rice is the host for F. semitectum, F. avenaceum and F. flocciferum in Iran. Pathogenicity tests were conducted in glass house. Following species were found to be associated with sheath rot of rice: S. oryzae, F. graminearum, F. udum, F. avenaceum, B. oryzae, A. padwickii. This is the first report in the world that F. udum and A. padwickii are the causal agents of the sheath rot on rice plants.