Heart failure in patients is associated with downregulation of mitochondrial quality control genes.

BACKGROUND: Mitochondrial dysfunction is one of key factors causing heart failure. We performed a comprehensive analysis of expression of mitochondrial quality control (MQC) genes in heart failure. METHODS: Myocardial samples were obtained from patients with ischemic and dilated cardiomyopathy in a terminal stage of heart failure and donors without heart disease. Using quantitative real-time PCR, we analysed a total of 45 MQC genes belonging to mitochondrial biogenesis, fusion-fission balance, mitochondrial unfolded protein response (UPRmt), translocase of the inner membrane (TIM) and mitophagy. Protein expression was analysed by ELISA and immunohistochemistry. RESULTS: The following genes were downregulated in ischemic and dilated cardiomyopathy: COX1, NRF1, TFAM, SIRT1, MTOR, MFF, DNM1L, DDIT3, UBL5, HSPA9, HSPE1, YME1L, LONP1, SPG7, HTRA2, OMA1, TIMM23, TIMM17A, TIMM17B, TIMM44, PAM16, TIMM22, TIMM9, TIMM10, PINK1, PARK2, ROTH1, PARL, FUNDC1, BNIP3, BNIP3L, TPCN2, LAMP2, MAP1LC3A and BECN1. Moreover, MT-ATP8, MFN2, EIF2AK4 and ULK1 were downregulated in heart failure from dilated, but not ischemic cardiomyopathy. VDAC1 and JUN were only genes that exhibited significantly different expression between ischemic and dilated cardiomyopathy. Expression of PPARGC1, OPA1, JUN, CEBPB, EIF2A, HSPD1, TIMM50 and TPCN1 was not significantly different between control and any form of heart failure. TOMM20 and COX proteins were downregulated in ICM and DCM. CONCLUSIONS: Heart failure in patients with ischemic and dilated cardiomyopathy is associated with downregulation of large number of UPRmt, mitophagy, TIM and fusion-fission balance genes. This indicates multiple defects in MQC and represents one of potential mechanisms underlying mitochondrial dysfunction in patients with heart failure.

Vitamin D Supplementation and Survival in Metastatic Colorectal Cancer.

BACKGROUND: Some studies have demonstrated that higher baseline plasma levels of 25-hydroxivitamin D [25(OH)D] are associated with a significant reduction in colorectal cancer (CRC) incidence. Patients with metastatic CRC (mCRC) tend to be vitamin D insufficient, but the effect of vitamin D on the survival of mCRC patients still remains uncertain. In this study, we evaluated the association between cholecalciferol 2,000 IU daily supplementation and survival of mCRC patients. METHODS: Seventy-two patients with mCRC were included. Seventy-one patients with 25(OH)D levels <75 nmol/l were randomized to receive standard chemotherapy or standard chemotherapy with cholecalciferol 2,000 IU daily. The primary endpoint was overall survival (OS) and the secondary endpoint was progression-free survival (PFS). The follow-up period was 46 mo. RESULTS: All but one patient (98.6%) was vitamin D insufficient. There was no statistically significant difference in OS or PFS between those who received vitamin D supplements and controls. CONCLUSIONS: The majority of patients with mCRC are vitamin D insufficient at the time of diagnosis. In our study, adding 2,000 IU of cholecalciferol daily for 2 yr to standard chemotherapy did not show any benefit in OS or PFS.

Mutation pattern of KRAS and BRAF oncogenes in colorectal cancer patients.

The aim of this study was to identify KRAS and BRAF gene mutations in colorectal cancer patients and to assess whether they are linked with clinicopathological features. The results of KRAS and BRAF mutation analysis could be used in the selection of patients for anti-EGFR therapy. All specimens were obtained during routine surgery of patients with colorectal carcinoma. The diagnoses were established by standard procedures and confirmed histopathologically. After DNA extraction, KRAS mutations were analyzed using quantitative real-time PCR and BRAF mutations were analyzed using real-time PCR by fluorescence melting curve analysis. Our results show that KRAS gene mutations were detected in 35.6% samples and the most frequent mutation was Gly12Val. BRAF gene mutation Val600Glu was detected in 8.5% samples. Statistical analysis revealed a significant association between the KRAS mutation and Dukes' stage (p=0.034), with the lowest frequency in Dukes'A, and between the KRAS mutation and histological grade (p=0.044), with no KRAS mutation found in poor differentiated tumors. The first data about KRAS and BRAF mutational status in the sample of Croatian population with colorectal cancer shows that the incidence of KRAS and BRAF mutations is within generally valid limits. Prospective studies are to be continued in order to determine whether these mutations contribute to progression of colorectal cancer.

Prevalence of asymptomatic chlamydial urethritis in military recruits in the Celje region, Slovenia.

The aim of this research was to evaluate the prevalence of asymptomatic chlamydial urethritis in military recruits in the Celje region (population 300,000), Slovenia. A first-void urine specimen was tested for Chlamydia trachomatis using the polymerase chain reaction assay. The research was supported by a questionnaire to obtain information on sexual behaviour of the participants. In the cross-sectional study from 1999 to 2001, 1272 asymptomatic recruits were included. None had received antibiotics in the previous two weeks. The mean age was 19.9 years. At the time of their first sexual experience the mean age was 16.6 years, whereas the age of their female sexual partners was 17.1 years. During their first sexual intercourse 77% of recruits used contraception (condom, diaphragm, contraceptive pill), most of those a condom (86%). The prevalence of asymptomatic chlamydial urethritis was 2.6% (95% confidence interval: 1.7 to 3.5). The mean age of those infected was 19.8 years. At the time of their first sexual experience the mean age was 16.2 years, whereas the age of their female sexual partners was 16.9 years. During their first sexual intercourse 57% of infected subjects used protection, half of which was a condom. Those who never or only occasionally used condoms were at a greater risk of being infected with C. trachomatis (adjusted odds ratio 2.04).

Kidney ischaemia-reperfusion injury and polyribosome structure.

BACKGROUND: Inhibition of protein synthesis and polyribosome disaggregation are the early events in cell injury provoked by various pathogenic mechanisms, including energy depletion. Polyribosome disaggregation might be expected to occur during ischaemia-reperfusion injury due to ischaemic energy depletion, but also due to detrimental effects of reactive oxygen species on various macromolecules and cellular structures. METHODS: Mouse kidney ischaemia-reperfusion injury was provoked by temporary clamping of the renal artery. The polyribosome sedimentation pattern was analyzed by sucrose density centrifugation of kidney postmitochondrial supernatant. RESULTS AND CONCLUSIONS: Ischaemia for 5 min in the mouse kidney provoked polyribosome disaggregation and an increase of monomer ribosome fraction which was augmented during 10-360 min of reperfusion. Recovery of polyribosome aggregates appeared between 6 and 24 h of reperfusion. Cycloheximide pretreatment prevented only polyribosome disaggregation caused by ischaemia and not that caused by reperfusion. This indicates different mechanisms of polyribosome disaggregation during ischaemia and reperfusion. It probably occurs in the former due to inhibition of initiation of translation, resulting in accumulation of unprogrammed monomer ribosomes, and in the latter due to the splitting of mRNA and breakdown of polyribosomes. Reperfusion did not increase ribonuclease activity in kidney cytosol, but increased the tissue concentration of malonaldehyde, indicating an augmentation in oxygen free radical generation. Possibly these may have caused a non-enzymatic breakdown of polyribosomes. However, pretreatment with allopurinol did not prevent polyribosome breakdown during ischaemia-reperfusion injury.

[Methemoglobinemia caused by accidental poisoning with metolachlor and metobromuron]. / Methemoglobinemija uzrokovana akcidentalnom intoksikacijom metolaklorom i metobromuronom.

An 81-year-old man was admitted in the emergency department approximately four hours after accidental, ingestion of an unknown quantity of herbicide "Galex 500 EC". This product contains 25% of metolachlor and 25% of metobromuron dissolved in xylene. In spite of the fact that the combination of aniline and urea-substituted derivatives is widely used in agriculture as herbicide, there are very few data available about their harmful effects on humans. These agents appear to be mildly toxic, and rarely has a major systemic effect been reported after the poisoning. On admittance, our patient showed remarkable cyanosis and his methaemoglobin level was 38.4% of the total haemoglobin, rising next day to 46.2%. Only mild transient signs of hypoxic effects on central nervous system were observed and the laboratory findings indicated mild haemolysis. Methylene blue was applied intravenously in a dose of 1.5 mg/kg (10 ml, 1% solution) on the second day of admission. Administration of methylene blue was very effective and the patient was discharged from the hospital fully recovered.

[Current use of bisphosphonates in clinical oncology]. / Primjena bifosfonata u internistickoj onkologiji.

Bisphosphonates represent nowadays a standard therapy of tumor induced hypercalcemia and are progressively more used in the treatment of tumor bone metastatic disease. Among several bisphosphonates, pamidronate is one of the most commonly used in clinical practice, so we also used it in succesful treatment of patients with breast cancer bone metastases. It has been shown that pamidronate reduces the frequency of hypercalcemia, bone pain and pathological fractures, although the mechanisms by which these effects are achieved are not completely clarified. Bisphosphonates are also important not only in treating patients with present metastases but also in prevention, or at least, delay of bone metastases onset. Recently, there are clinical trials examining the so called adjuvant therapy, that means the use of bisphosphonates in prevention of bone metastases in high risk breast cancer patients without distant metastases. In addition to breast cancer, multiple myeloma is another area of successful bisphosphonate application. In this paper we present some of the clinical results following the use of pamidronate in breast cancer- and hypernephroma-patients with hypercalcemia.

Changes in serum lipid and lipoprotein levels in postmenopausal patients with node-positive breast cancer treated with tamoxifen.

Tamoxifen has been used for a long time as an adjuvant hormonal treatment in breast cancer patients. We studied 62 newly diagnosed postmenopausal women, aged 50-79 years, with node-positive breast cancer and receiving adjuvant tamoxifen (20 mg per day). Total serum cholesterol, triglycerides, HDL-cholesterol, LDL-cholesterol, VLDL-cholesterol, apo AI, apo AII, apo B and Lp(a) were determined before the surgery and 3, 6, 9, 12 and 24 months after starting tamoxifen treatment. Tamoxifen significantly reduced total serum cholesterol (6.13+/-1.20 mmol/L vs 5.21+/-1.05 mmol/L) (P <0.01), LDL-cholesterol (3.72+/-0.70 mmol/L vs 2.93+/-0.51) (P <0.01) and Lp(a) (0.11+/-0.07 g/L vs 0.02+/-0.01 g/L) (P < 0.01). There were no changes in triglycerides or HDL-cholesterol serum levels during tamoxifen treatment. The results indicate that an additional beneficial effect of adjuvant tamoxifen therapy may be that it decreases cardiovascular risk in such patients.

[Hormonal therapy with aromatase inhibitor in advanced breast cancer]. / Hormonsko lijecenje uznapredovalog raka dojke blokatorom aromataze.

We investigated the aminogluthetimide therapy effect on 30 postmenopausal women with advanced breast cancer previously treated with tamoxifen as a first-line hormonal treatment. Aminogluthetimide exhibits anticancer effect by inhibition of aromatase enzyme which plays a key role in the conversion of androgen to estrogen in peripheral adipose tissue. This pathway presents the main source of estrogen in postmenopausal women. Mean duration of the treatment was 14.3 months. Complete remission has been achieved in 10% of all patients, and partial remission in 16.6%. Mean duration of free intervals was 16.1 months in the group with ER+/PgR+ hormonal status, which is significantly longer compared to the ER+/PgR- and ER-/PgR+ groups where it was 11.8 months (p < 0.01). Aminogluthetimide treatment led to significant decrease in estradiol (E2) and dehydroepiandrosterone-sulphate (DHAS) levels in plasma. Thus, the effect of aminogluthetimide therapy as a second-line hormonal therapy has a benefit in the treatment of metastatic hormon-dependent breast cancer patients.

Haematological features of the population of the area of Croatia, Yugoslavia, endemic for Balkan nephropathy.

Normochromic, normocytic anaemia is a sign recognized as essential for the diagnosis of Balkan endemic nephropathy, although its relationship to the disease is still unclear. The aim of this study was to investigate whether a random sample of the population of a village endemic for nephropathy differed from the population of a village with no clinical case of nephropathy with respect to certain basic haematological parameters. During a screening campaign in 1984, 133 blood samples were collected from the endemic village and 40 from the nonendemic village and analysed for a number of haematological parameters; in 1991, 449 samples were collected in the endemic village and 156 in the nonendemic village and analysed for haemoglobin content and red blood cell count. Whereas in 1984 the haemoglobin content and red blood cell count were significantly lower in the endemic village (p less than 0.01), in 1991 the erythrocyte count was much lower in the nonendemic village and there was no difference in haemoglobin concentration. Several controversial explanations, all of them speculative, are offered.