TAP1 gene polymorphisms and nasopharyngeal carcinoma risk in a Tunisian population

To find out whether polymorphisms 333-Ile/Val and 637-Asp/Gly of the transporter part of the antigen processing 1 gene (TAP1) are associated with the development of nasopharyngeal carcinoma (NPC), we studied a total of 374 subjects (209 patients and 165 controls). We used the amplification refractory mutation system polymerase chain reaction (ARMS-PCR) method for analyzing the TAP1 gene polymorphisms. We found a significant difference between the patients and the controls in both the TAP1 codon 333 and codon 637 (P = 0.009 and P = 0.002, respectively). We also found that genotypes with the A allele were present in 206 patients with NPC and 155 controls (98.5 vs. 93.9%; P = 0.032; OR = 4.43) and that genotypes with the B allele were more often present in the control group (45 vs. 32%; P = 0.004; OR = 0.48), suggesting a significant positive association of the A allele with NPC risk and a protective role of the B allele. We have observed an association between the distribution of TAP1 alleles and the NPC patient's age at onset, compared with controls. These results back up the fact that the etiology of NPC in intermediate-risk countries is completely different in each peak of age prevalence and that each peak may possess its own particular oncogenic mechanism.     

Antenatal diagnosis of sacrococcygeal teratomas: prognostic features

During a 6-year span the prenatal ultrasound diagnosis of a sacrococcygeal mass was made eight times at the High-Risk Perinatal Centers of Case Western Reserve University. The gestational age at the time of diagnosis ranged from 21 to 35 weeks. In one of the pregnancies, the affected fetus was one of a set of fraternal twins. Two patients were delivered vaginally and five were delivered by cesarean section. One fetus died in utero. In seven the diagnosis of sacrococcygeal teratoma (SCT) was confirmed histologically. In the eighth the lesion was a fungating malignant melanoma of the lower sacral region. The decision as to mode of delivery was made based on the size of the tumor relative to the biparietal diameter and fetal presentation. Four of the six remaining patients with SCT survived. In the three with fatal outcome, the ratio of infant weight to tumor weight was below 1.7. This measurement is a clear indication of the very large size of these lesions. The increased blood flow through these tumors can lead to fetal cardiac failure, hydrops, and death. With the almost routine use of ultrasound, more SCT may be identified antenatally. Included in this group and referred to tertiary care centers will be nonviable fetuses as well as very small fetuses with exceptionally large tumors; this will raise the overall mortality in this group of patients traditionally regarded by pediatric surgeons as having a good outlook.     

Matrix metalloproteinase-1 (-1607) 1G/2G and -9 (-1562) C/T promoter polymorphisms: susceptibility and prognostic implications in nasopharyngeal carcinomas

BACKGROUND: Matrix metalloproteinases (MMPs) are proteolytic enzymes that play important roles in tumor invasion and metastasis by degrading extracellular matrix components. Genetic variations in promoter regions of MMP genes, affecting their expression, have been associated with susceptibility to cancers. The aim of this study was to investigate the susceptibility and prognostic implications of the MMP-1 (-1607) 1G/2G and MMP-9 (-1562) C/T polymorphisms in nasopharyngeal carcinomas. METHODS: The variation of the MMP-1 and MMP-9 promoter regions in 174 patients with NPC and 171 healthy control subjects was investigated. Association of the clinico-pathologic parameters and the genetic markers with the rates of the nasopharyngeal carcinoma-specific overall survival and the disease-free survival were assessed using univariate and multivariate analyses. RESULTS: No association was found between genetic variation in MMP-9 and the risk of NPC occurrence. In contrast, a significantly increased risk of NPC was associated with the homozygous MMP-1 (-1607) 2G2G genotype (OR=2.27; p=0.02). A significant association was also found between the 2G2G genotype and the aggressive forms of NPC as defined by large tumor size (T3-T4), lymph node metastasis and advanced stages (III-IV) at the time of diagnosis. Moreover, an association was ascertained between the MMP-1 polymorphism and gender (OR=2.90; p=0.02). In univariate analysis, the MMP-1 (-1607) 2G allele showed a significant association with reduced disease-free survival for NPC patients (p=0.03). CONCLUSIONS: The genetic variation in MMP-1 may represent a marker for the increased risk of nasopharyngeal carcinoma.     

Cyanobacterial extracts containing microcystins affect the growth,nodulation process and nitrogen uptake of faba bean (<Emphasis Type="Italic">Vicia faba</Emphasis> L., Fabaceae)

The use of irrigation water containing cyanobacterial toxins may generate a negative impact in both yield and quality of agricultural crops causing significant economic losses. We evaluated the effects of microcystins (MC) on the growth, nodulation process and nitrogen uptake of a Faba bean cultivar (Vicia faba L., Fabaceae), particularly the effect of MC on rhizobia-V. faba symbiosis. Three rhizobial strains (RhOF4, RhOF6 and RhOF21), isolated from nodules of local V. faba were tested. The exposure of rhizobia to MC showed that the toxins had a negative effect on the rhizobial growth especially at the highest concentrations of 50 and 100 μg/l. The germination of faba bean seeds was also affected by cyanotoxins. We registered germination rates of 75 and 68.75% at the toxin levels of 50 and 100 μg/l as compared to the control (100%). The obtained results also showed there was a negative effect of MC on plants shoot, root (dry weight) and total number of nodules per plant. Cyanotoxins exposure induced a significant effect on nitrogen assimilation by faba bean seedlings inoculated with selected rhizobial strains RhOF6 and RhOF21, while the effect was not significant on beans seedling inoculated with RhOF4. This behavior of tolerant rhizobia-legumes symbioses may constitute a very important pathway to increase soil fertility and quality and can represent a friendly biotechnological way to remediate cyanotoxins contamination in agriculture.     

Influence of HLA disparity, immunosuppressive regimen used, and type of kidney allograft on production of anti-HLA class-I antibodies after transplant and occurrence of rejection

We studied the effects of HLA disparity, immunosuppressive regimen used, and the type of kidney allograft on production of anti-HLA antibodies after transplant and the occurrence of rejection episodes. Five living-unrelated donors and 4 living-related donors kidney recipients received quadruple therapy (including sirolimus and mycophenolate mofetil). Fifteen living-unrelated donors and 19 living-related donors received triple therapy (excluding sirolimus). A single bolus of 4 to 6 mg/kg rabbit anti-human T-lymphocyte immune serum was included with both regimens. Recipients were studied over a 3-year period. Human leukocyte antigen profiles were determined by DNA (SSP) typing, and anti-HLA class-I antibodies were determined by the complement-dependent microcytotoxicity assay and an enzyme-linked immunosorbent assay. The degree of HLA disparity did not appear to affect anti-HLA antibody production or the occurrences of rejection episodes. None of the patients who received quadruple therapy developed anti-HLA class-I antibodies. Two living-unrelated donors and 2 living-related donors recipients who received triple therapy developed anti-HLA class-I antibodies. One of the 2 living-unrelated donors antibody-positive patients rejected the kidney and returned to dialysis, and the other patient has normal graft function 3 years after the transplant. The 2 living-related donors patients with normal graft function were antibody-positive 1 year after the transplant but were antibody-negative at 2 and 3 years after transplant. Sirolimus appeared to inhibit production of antibodies after transplant. Moreover, use of present day immunosuppressive agents diminishes the role of HLA matching in relation to the occurrence of rejection episodes.     

Protective Role of Native Rhizospheric Soil Microbiota Against the Exposure to Microcystins Introduced into Soil-Plant System via Contaminated Irrigation Water and Health Risk Assessment

Microcystins (MCs) produced in eutrophic waters may decrease crop yield, enter food chains and threaten human and animal health. The main objective of this research was to highlight the role of rhizospheric soil microbiota to protect faba bean plants from MCs toxicity after chronic exposure. Faba bean seedlings were grown in pots containing agricultural soil, during 1 month under natural environmental conditions of Marrakech city in Morocco (March–April 2018) and exposed to cyanobacterial extracts containing up to 2.5 mg·L⁻¹ of total MCs. Three independent exposure experiments were performed (a) agricultural soil was maintained intact “exposure experiment 1”; (b) agricultural soil was sterilized “exposure experiment 2”; (c) agricultural soil was sterilized and inoculated with the rhizobia strain Rhizobium leguminosarum RhOF34 “exposure experiment 3”. Overall, data showed evidence of an increased sensitivity of faba bean plants, grown in sterilized soil, to MCs in comparison to those grown in intact and inoculated soils. The study revealed the growth inhibition of plant shoots in both exposure experiments 2 and 3 when treated with 2.5 mg·L⁻¹ of MCs. The results also showed that the estimated daily intake (EDI) of MCs, in sterilized soil, exceeded 2.18 and 1.16 times the reference concentrations (0.04 and 0.45 µg of microcysin-leucine arginine (MC-LR). Kg⁻¹ DW) established for humans and cattle respectively, which raises concerns about human food chain contamination.     

Test–retest and intra-observer repeatability of two-, three- and four-dimensional perineal ultrasound of pelvic floor muscle anatomy and function

The aims of the present study were to evaluate test–retest intra-observer repeatability of ultrasound measurement of the morphology and function of the pelvic floor muscles (PFMs). Seventeen subjects were tested twice. Two-, three- and four- dimensional ultrasound recorded cough, huff, muscle morphology and PFM contraction, respectively. Analyses were conducted offline. Measurements of levator hiatal dimensions demonstrated intra-class correlation coefficient (ICC) values of 0.61, 0.72, 0.86 and 0.92, for the anterior-posterior dimension, transverse dimension, resting area and narrowing during contraction, respectively. Muscle thickness showed variable reliability. ICC values for measurement of the position of the bladder neck were 0.86 and 0.82 at rest, in the vertical and horizontal direction. Displacement of the bladder neck during contraction, huff and cough demonstrated ICC values of 0.56, 0.59 and 0.51, respectively. Perineal ultrasound is a reliable method for measuring most of the tested parameters of morphology and function of the PFMs.     

Phytotoxic effects of cyanobacteria extract on the aquatic plant Lemna gibba: microcystin accumulation, detoxication and oxidative stress induction

The occurrence of toxic cyanobacteria in the aquatic environment constitutes a serious risk for the ecological balance and the functioning of ecosystems. The presence of cyanotoxins in ecosystems could have eventual adverse effects on aquatic plants, which play an important biological role as primary producers. The original aim of this study was to investigate microcystin (MC) accumulation, detoxication and oxidative stress induction in the free-floating aquatic vascular plant Lemna gibba (Duckweed, Lemnaceae). Experiments were carried out with a range of MC levels, obtained from toxic Microcystis culture extracts (0.075, 0.15, 0.22 and 0.3 microg equiv.MC-LR mL(-1)). During chronic exposure of the plant to MC, we examined the growth, photosynthetic pigment contents and also the physiological behavior related to toxin accumulation, possible biodegradation and stress oxidative processes of L. gibba. For the last reason, changes in peroxidase activity and phenol compound content were determined. This is a first report using phenol compounds as indicators of biotic stress induced by MC contamination in aquatic plants. Following MC exposure, a significant decrease of plant growth and chlorophyll content was observed. Also, it was demonstrated that L. gibba could take up and bio-transform microcystins. A suspected MC degradation metabolite was detected in treated Lemna cells. In response to chronic contamination with MCs, changes in the peroxidase activity and qualitative and quantitative changes in phenolic compounds were observed after 24h of plant exposure. The physiological effects induced by chronic exposure to microcystins confirm that in aquatic ecosystems plants coexisting with toxic cyanobacterial blooms may suffer an important negative ecological impact. This may represent a sanitary risk due to toxin bioaccumulation and biotransfer through the food chain.