BICD1 and Chromosome 18 Polymorphisms Associated With Recipients' Telomere Length Affect Kidney Allograft Function After Transplantation

BACKGROUND

Reports regarding recipient's nonmodifiable genetic factors affecting telomerase activity and thus allograft function are lacking. Therefore the aim of this study was to analyze the associations between recipients' rs2735940 hTERT, rs2630578 BICD1, and rs7235755 chromosome 18 polymorphisms and kidney function after transplantation.

METHODS

The study enrolled 119 white Polish kidney allograft recipients (64 men, 55 women; overall mean age, 47.3 ± 14.0 y). To identify genotypes of the studied polymorphisms, real-time polymerase chain reaction was performed.

RESULTS

There were statistically significant differences in distribution of rs7235755 chromosome 18 polymorphism genotypes and alleles between recipients with delayed graft function (DGF) and without DGF (P = .03). The presence of A allele was significantly associated with higher risk of DGF occurrence (AA + GA vs GG: OR, 3.25 [95% CI, 1.16-9.14]; P = .02; GA vs GG: OR, 4.00 [1.35-11.82]; P = .01). Analysis of the rs2630578 BICD1 gene polymorphism genotypes revealed statistically significant differences in long-term creatinine concentrations. The presence of C allele of this polymorphism was significantly associated with higher creatinine concentrations 24, 36, and 18-48 months after transplantation (GC + CC vs GG: P = .008, P = .008, and P = .01, respectively).

CONCLUSIONS

Recipients' polymorphisms of genes associated with telomere length, BICD1 and chromosome 18, but not hTERT, affect kidney allograft early and long-term function after transplantation. There is an urgent need for explanation of these observations in genome-wide association studies.

Gromerulocystic Kidney Disease in a Transplanted Kidney: Case Report

The patient was a 28-year-old man with chronic kidney disease in stage 5 and in the course of chronic membranoroliferative glomerulonephritis. The patient was treated for a period of 2 months using peritoneal dialysis. In September 2014, he had a kidney transplant from a deceased donor. Four months after transplantation the patient was admitted to the hospital for a protocol biopsy. His creatinine was 1.5 mg/dL and urea was 59 mg/dL, urinalysis was normal in blood count with a normocytic anemia-hemoglobin level of 7.8 mmol/L. We obtained a histopathological evaluation of the cortex and medulla of the kidney. Glomeruli dilatation of Bowman space with reduced glomerular capillary tufts was found in the section. Histopathological evaluation indicated gromerulocystic kidney disease in a transplanted kidney.

Oxidative stress indices in rats under immunosuppression

Immunosuppressants lead to generation of reactive oxygen species (ROS). Oxidative stress (OxS) can initiate chronic allograft nephropathy (CAN). The most active antioxidant enzymes, superoxide dysmutase (SOD) and catalase (CAT), are present in erythrocytes. Glutathione peroxidase (GPx) is produced in the proximal tubules of nephrons. Malonyldialdehyde (MDA) concentrations are a marker of OxS intensity in plasma. In vitro and animal model studies have shown increased or decreased OxS during treatment with tacrolimus (Tac) or cyclosporine (CyA). Results obtained in humans after solid organ transplantation have been contradictory, because of confounding factors such as ischemia-reperfusion injury, donor and recipient ages, endothelial injury, and comorbidity. The aim of this study was to assess the intensity of OxS among rats under chronic immunosuppression (IS) without a transplantation. We examined 49 male Wistar rats. IS started at 12 weeks of age was continued for 6 months: group I were controls (n=7); group II, Tac+sirolimus (Rapamycin [Rapa])+corticosteroids (CS; n=6); group III, CyA+Rapa+CS (n=4 of which 2 died); group IV, Rapa+mycophenolate mofetil (MMF)+CS (n=6); group V, CyA+MMF+CS (n=6); group VI, CsA+MMF+CS for 3 months followed by conversion to Rapa (n=6); group VII, Tac+MMF+CS (n=6 rats); and group VIII, Tac+MMF+CS for 3 months followed by conversion to Rapa (n=6). The drug doses were as follows: Tac 4 mg/kg/d; MMF 20 mg/kg/d; CyA 5mg/kg/d; Rapa 0.5 mg/kg/d; and CS 4 mg/kg/d. Multiple regression analysis revealed that all IS drugs decreased GPx activity (P<.001) except CS, which increased it (P<.0001). Multiple regression analysis showed that CsA and Tac decreased plasma MDA concentrations (P<.01), whereas CS increased them (P<.05). In conclusion, all IS drugs except CS damage proximal tubules of nephrons.

Mureinolytic ability of the rumen ciliate Diploplastron affine

Rumen ciliate protozoa intensively engulf bacteria. However, their ability to utilize murein which is the main polysaccharide of bacterial cell wall has hardly been recognized. The present study concerns the ability of the rumen protozoa Diploplastron affine to digest and ferment murein. The ciliates were isolated from the rumen fluid and grown in vitro or inoculated into the rumen of defaunated sheep. The results of long-term cultivation of protozoa showed a positive correlation between their number and murein content in the culture medium. It was also found that bacteria-free D. affine ciliates incubated with or without murein produced volatile fatty acids at the rate of 12.3 and 8.7 pmol/h per protozoan, respectively, acetic, butyric and propionic acids being the three main acids released to the medium. Enzyme studies performed with the use of protozoan cell extract prepared from bacteria-free ciliates degraded murein at a rate of 25 U/mg protein per h; two mureinolytic enzymes were identified by zymographic technique in the examined preparation.

The ability of the rumen protozoan Eudiplodinium maggii to utilize chitin

The ability was determined of the rumen ciliate Eudiplodinium maggii to utilize chitin from fungal cell wall. Cultivation experiments shoved that the population concentration (number of ciliates in vitro) was positively correlated with chitin doses. Cell extract prepared from the bacteria-free ciliates degraded colloidal chitin releasing 2.0 micromol reducing sugar per mg protein per h. End products of this reaction were chitotriose and N-acetylglucosamine. Incubation of the bacteria-free ciliates with chitin resulted in an increase in the concentration of acetic, propionic and butyric acids in the incubation medium. The production rate of total volatile fatty acids (VFA) by ciliates incubated with and without chitin was 45.0 and 30.5 pmol VFA per protozoan, respectively, the molar proportion of particular acids remaining unchanged.

The activity of erythrocyte sodium-proton exchanger in women with pregnancy- induced hypertension

BACKGROUND

Hypertension that develops after 20 gestational weeks and is defined as pregnancy-induced hypertension (PIH). The main cause of PIH is vasoconstriction and the thickening of vascular media, which decreases vascular capacity and increases peripheral resistance. One of the theories postulated to explain this phenomenon is that a transmembrane sodium transport disorder causes an increase in intracellular sodium concentration. In the latest literature, special attention is paid to the role of the increased intracellular sodium concentration in the pathogenesis of essential hypertension (EH). One of the best documented phenotypes for EH is the increased activity of the sodium-proton exchanger (NHE). The aim of this study was to assess if increased NHE activity could be the mechanism responsible for the development of PIH.

SUBJECTS AND METHODS

The study included 30 women: 10 pregnant women with PIH after gestational week 30, 10 women with physiological pregnancy after 30 gestational weeks, and 10 healthy non-pregnant women. NHE activity was determined according to Orlov's method as amiloride-sensitive H(+) efflux from acid-loaded cells.

RESULTS

The NHE activity in the group of women with PIH was significantly higher than that in women with physiological pregnancy: 10.09 +/- 1.65 vs. 6.81 +/- 2.3 mmol/L RBC/h (p < 0.049) and in the group of non-pregnant women: 10.09 +/- 1.65 vs. 7.56 +/- 1.66 mmol/L RBC/h (p < 0.029). Erythrocyte NHE activity did not differ in the group of women with physiological pregnancy and in the group of non-pregnant women.

CONCLUSION

These results seem to suggest that erythrocyte NHE activity is elevated in PIH pregnancies.

Low frequency of the CHEK2*1100delC mutation among breast cancer probands from three regions of Poland

The 1100delC germline mutation of the CHEK2 gene appears to contribute significantly to the overall breast cancer incidence in some West and North European countries, but seems to be much less frequent among breast cancer patients from other regions of Europe. In the present study we found, respectively, 3/487, 1/296 and 0/279 carriers of this mutation among breast cancer patients from the East-Central, South-East and West-Central regions of Poland. Two carriers of the 1100delC mutation were found among 120 patients with bilateral breast cancer, but only one had a previous family incidence of breast cancer. We found no carriers among 182 patients with unilateral breast cancer with family history of this tumor and among 64 patients with breast cancer and a second primary tumor at an other site. We conclude that the 1100delC mutation of the CHEK2 gene contributes little to the overall breast cancer burden in Poland, including familial cases of this malignancy. Further studies are still needed to evaluate the contribution of this mutation to the development of bilateral breast tumors.

The presence of hereditary BRCA1 gene mutations in women with familial breast or ovarian cancer and the frequency of occurrence of these tumours in their relatives

In 48 women with familial breast cancer as well as in 22 women with familial ovarian cancer, the presence of pathogenic mutations in BRCA1 gene were found in 35.4% and 54.6% of patients, respectively. From the patients with mutations we created two groups: the CaM--probands with breast cancer and CaOv--probands with ovarian cancer. The probands with breast cancer were younger by a mean of five years than the probands with ovarian cancer (p = 0.048).

METHODS

The PCR-SSCP procedure was used to find mutations in the BRCA1 gene. Fragments suspected of mutation were subjected to nucleotide sequencing.

RESULTS

In the CaM group, which consisted of 17 women with breast cancer, the following mutations in the BRCA1 gene were detected: 5382insC, T300G, 3819del5 and IVS20+60ins12. The probands of the CaM group and their relatives developed a total of 49 breast and ovarian cancers. Among all these tumours the breast cancers of the probands made up 34.7%, the breast cancers of proband relatives made up 57.1% and the ovarian cancers of probands and their relatives made up only 8.2%. The CaOv group consisted of 12 probands with ovarian cancers in whom we detected only two kinds of mutations: 5382insC and 185delAG. The probands of the CaOv group and their relatives developed a total of 38 ovarian and breast cancers. Among all these tumours the ovarian cancers of the probands made up 31.6%, the ovarian cancers of their relatives made up 34.2% and the breast cancers of the relatives 34.2% of tumours. In the probands with breast or ovarian cancer the predominant mutation was 5382insC--in the BRCA1 gene detected in 76.5%, and 91.7%, respectively. Despite the predominant presence of the same mutation in probands from both groups the ratio of the number of breast cancers to the number of ovarian cancers in their relatives differed significantly (p = 0.0003).

CONCLUSION

This data shows that the presence of the 5382insC mutation in the BRCA1 gene is not always associated with the development of ovarian cancer. It is very likely that the development of ovarian cancer requires some additional factor, which was common among the familial ovarian cancer patients, and was almost inexistent among the familial breast cancer patients. On the other hand, the development of ovarian cancer at a later age than breast cancer in probands suggests that some factors exist which slow down the development of ovarian cancer or which accelerate the development of breast cancer.

BRCA2 germline mutations in male breast cancer patients in the Polish population

Breast cancer is a rare disease in men. Germ-line mutations in BRCA2 and androgen receptor (AR) genes are thought to be responsible for a proportion of male breast cancer cases. The present study was performed on a series of 37 consenting patients not selected for family history of breast/ovarian cancer. The entire coding region of the BRCA2 gene and two exons of the AR gene were analyzed for germ-line mutations to evaluate the association between BRCA2 and AR genes and male breast cancer in Poland. We identified four frameshift mutations (11%) in exons 10, 11, 17 and 18, two of them were novel: 6495del3insC and 8457insA. Three missense unclassified variants (8%) of the BRCA2 gene were also identified. The frequencies of missense alterations were examined in a set of 200 chromosomes. No alteration of the AR gene was found. We did not observe much difference in clinicopathological features between carriers and non-carriers of BRCA2 mutations. Five of 37 patients (14%) had a family history of breast cancer, in one first- or second-degree relative, among the latter was one mutation carrier. The results of this study suggest that germ-line BRCA2 mutations account for rather small proportion of male breast cancer in Poland.

High frequency of recurrent mutations in BRCA1 and BRCA2 genes in Polish families with breast and ovarian cancer

Germ-line mutations in BRCA1 and BRCA2 genes result in a significantly increased risk of breast and ovarian cancer. Other genes involved in an increased predisposition to breast cancer include the TP53 gene, mutated in Li-Fraumeni syndrome. To estimate the frequency of germ-line mutations in these three genes in Upper Silesia, we have analyzed 47 breast/ovarian cancer families from that region. We found five different disease predisposing mutations in 17 (36%) families. Twelve families (25.5%) carried known BRCA1 mutations (5382insC and C61G), four families (8.5%) carried novel BRCA2 mutations (9631delC and 6886delGAAAA), and one family (2%) harbored novel mutation 1095del8 in the TP53 gene, which is the largest germline deletion in coding sequence of this gene identified thus far. The 5382insC mutation in BRCA1 was found in 11 families and the 9631delC mutation in BRCA2 occurred in three families. These two mutations taken together contribute to 82% of all mutations found in this study, and 30% of the families investigated harbor one of these mutations. The very high frequency of common mutations observed in these families can only be compared to that reported for Ashkenazi Jewish, Icelandic, and Russian high-risk families. This frequency, however, may not be representative for the entire Polish population. The observed distribution of mutations will favor routine pre-screening of predisposed families using a simple and cost-effective test.

Biomechanics of the pulmonary autograft valve in the aortic position

Pulmonary autograft valve replacement has been simulated by implanting the pulmonary valve into the aortic position of the same cadaver heart from both human and porcine sources. The forces acting on the pulmonary valve leaflets have been calculated on the basis of a triaxial ellipsoid mathematical model. These forces on the pulmonary autograft valve were shown to be essentially similar to those previously reported for aortic valve leaflets. Biomechanical measurements have been made on the simulated autograft valves and on the isolated pulmonary valve cusps. The tensile strengths of the pulmonary valve cusps in both circumferential and radial directions were roughly three times greater than those of aortic valve cusps. This indicated the ability of the pulmonary valves to accept, ab initio, aortic valve closing pressures. Pressure-induced changes in dimension, calculated on the basis of diameters of the simulated pulmonary autograft root, also indicated that the distensibility of the autograft valve was limited. It reached a maximum at 30 mm Hg (4 kPa) without any suggestion of further distension to the point of distortion and incompetence. The combination of the calculated forces acting on the valve and the biomechanical measurements have shown that pulmonary valves used as autograft aortic valve replacements are able to tolerate aortic pressures from the time of implantation. These experimental results from simulated autografts support the clinical use of this valve over the past 13 years.

[Prevention of epilepsy in children following birth trauma]

In a group of 120 children with prenatal and postnatal trauma 31 children with epileptic seizures were found who accounted for 25.8% of neuropsychiatric complications in this group. Epilepsy was more frequent in children with a history of asphyxia than after other forms of perinatal trauma. Seizures were observed either immediately after birth or up to the age of 100 months. In children with delayed onset of seizures evidence of abnormal behaviour with excessive motor agitation, sleep and appetite disturbances was found from the very birth. Besides prophylactic measures applied to avoid complications of pregnancy and labour it is indispensable to separate the children with perinatal trauma and group them for further neuropsychiatric observation in outpatient clinics and to begin treatment which may prevent development of frank epilepsy in at least a part of these children and may contribute to better rehabilitation of brain-damaged children.