Correlation between antimicrobial consumption and antimicrobial resistance of Pseudomonas aeruginosa in a hospital setting: a 10-year study

WHAT IS KNOWN AND OBJECTIVE

Antimicrobial resistance is one of the greatest threats to human health. One of the most important factors leading to the emergence of resistant bacteria is overuse of antibiotics. The purpose of this study was to investigate the correlation between antimicrobial usage and bacterial resistance of Pseudomonas aeruginosa (P. aeruginosa) over a 10-year period in the Clinical Center Niš, one of the biggest tertiary care hospitals in Serbia. We focused on possible relationships between the consumption of carbapenems and beta-lactam antibiotics and the rates of resistance of P. aeruginosa to carbapenems.

METHODS

We recorded utilization of antibiotics expressed as defined daily doses per 100 bed days (DBD). Bacterial resistance was reported as the percentage of resistant isolates (percentage of all resistant and intermediate resistant strains) among all tested isolates.

RESULTS AND DISCUSSION

A significant increasing trend in resistance was seen in imipenem (P < 0·05, Spearman ρ = 0·758) and meropenem (P < 0·05, ρ = 0·745). We found a significant correlation between aminoglycoside consumption and resistance to amikacin (P < 0·01, Pearson r = 0·837) and gentamicin (P < 0·01, Pearson r = 0·827). The correlation between the consumption of carbapenems and resistance to imipenem in P. aeruginosa shows significance (P < 0·01, Pearson r = 0·795), whereas resistance to meropenem showed a trend towards significance (P > 0·05, Pearson r = 0·607). We found a very good correlation between the use of all beta-lactam and P. aeruginosa resistance to carbapenems (P < 0·01, Pearson r = 0·847 for imipenem and P < 0·05, Pearson r = 0·668 for meropenem).

WHAT IS NEW AND CONCLUSION

Our data demonstrated a significant increase in antimicrobial resistance to carbapenems, significant correlations between the consumption of antibiotics, especially carbapenems and beta-lactams, and rates of antimicrobial resistance of P. aeruginosa to imipenem and meropenem.

Current and future anti-HER2 therapy in breast cancer

The therapeutic strategy for breast cancer with the use of targeted drugs is, at present, mainly focused on coping with HER2. Currently, lapatinib and trastuzumab are in widespread use. Virtually all completed and in progress clinical trials have demonstrated a significant enhancement in the rate of pathologic complete response (pCR), the primary endpoint in these studies, in cases of patients with HER2-positive breast cancer that received trastuzumab in the neoadjuvant setting. Use of lapatinib in the neoadjuvant setting should be considered experimental. When a 12-month course of trastuzumab was added to adjuvant chemotherapy, the disease-free survival (DFS) was greater and the overall survival (OS) was also greater. Although trastuzumab is approved as single-agent therapy, most patients are treated with trastuzumab plus cytotoxic agents. Trastuzumab, administered as single agent, produces durable objective responses and is well tolerated by women with HER2-overexpressing metastatic breast cancer that has progressed after chemotherapy for metastatic disease. Dual targeting approach with a combination of trastuzumab and lapatinib improved progression-free survival (PFS) as compared with lapatinib alone in patients with metastatic breast cancer who have not had a response to trastuzumab. The combination of pertuzumab plus trastuzumab plus docetaxel, as compared with placebo plus trastuzumab plus docetaxel, when used as first-line treatment for HER2-positive metastatic breast cancer, significantly prolonged PFS. Novel anti-HER2 targeted therapies are needed to utilise novel approaches to combat trastuzumab resistance.

Dietary flavonoid intake and colorectal cancer risk: evidence from human population studies

Flavonoids are biologically active polyphenolic compounds widely distributed in plants. More than 5000 individual flavonoids have been identified, which are classified into at least 10 subgroups according to their chemical structure. Flavonoids of 6 principal subgroups- flavonols, flavones, anthocyanidins, catechins, flavanones, and isoflavones- are relatively common in human diets. Flavonoids are a large and diverse group of phytochemicals and research into their anti-carcinogenic potential with animal and cellular model systems supports a protective role. Whether dietary intake of flavonoids is protective against colorectal cancer in humans cannot be easily extrapolated from cell line and animal findings. Epidemiological assessment of the relationship between dietary flavonoid intake and colorectal cancer is limited, with different case-control and cohort study design investigating different combinations of flavonoids. Epidemiologic studies on flavonoid intake and colorectal cancer risk that were conducted yielded inconsistent results, with positive, inverse, and null associations. Because only a very limited number of epidemiological studies have been conducted to examine the associations of dietary intake of flavonoids with colorectal cancer risk, it is premature to make public health recommendations at this time. However, the data to date are promising and emphasize the need for further investigation of these important bioactive plant compounds. This review summarises the epidemiological evidence from case-control and cohort studies on the associations of dietary flavonoid intake with the risk for colorectal cancer. The difficulties in investigating this topic and possibilities for further research are then discussed.

Hypotensive, vasorelaxant and cardiodepressant activities of the ethanol extract of Sideritis raeseri spp. raeseri Boiss & Heldr

Sideritis raeseri spp. raeseri Boiss & Heldr is a native plant from the Mediterranean region that is used due to its medicinal and culinary properties. The aim of this study was to evaluate the effects of ethanol extract of S. raeseri on the blood pressure, vascular and cardiac contractions. Arterial blood pressure was registered directly from the carotid artery in the anaesthetized rabbits. Aortic rings and the spontaneously beating atria were mounted in tissue bath. An intravenous injection of extract of S. raeseri (0.025-7.5 mg/kg) caused a dose dependent decrease of the arterial pressure and heart rate, with EC(50) value of 24.31±3.87 mg/kg and 88.14±7.51 mg/kg, respectively. In aortic preparations precontracted with KCl (80 mM), the extract of S. raeseri (0.005-1.5 mg/ml) elicited a vasodilatator action (EC(50) 0.11±0.008 mg/ml). In spontaneously beating rat atria, the extract of S. raeseri (0.005-1.5 mg/ml) produced decrease of chronotropic and inotropic activity (with EC(50) value of 0.63±0.03 mg/ml and 0.40±0.08 mg/ml). Administration of verapamil induced inhibition of force and rate of the atrial contraction. These results demonstrate that the ethanol extract of Sideritis raeseri spp. raeseri Boiss & Heldr can produce hypotension, vasodilatation, negative chronotropic and inotropic effects.

Case-control design as investigative approach to assessing cancer etiology: development and future perspectives

The case-control method evolved out of analyses of series of cases. The analytic form of the case-control study can be found in the 19th century medical literature, but did not appear to be viewed as a special or distinct methodology. The first modern case-control study was the Janet Lane-Claypon's study of breast cancer in 1926, but the design was used only sporadically in medicine until 1950, when 4 published casecontrol studies linked smoking and lung cancer. These 1950s studies synthesized the essential elements of the case-control comparison, produced a conceptual shift within epidemiology, and laid the foundation for the rapid development of the case-control design in the subsequent half century. The powerful consistency of these case-control studies, and the replication of their findings in later prospective studies, promoted the general acceptance of the case-control study as a scientific tool in clinical research. Newer case-control studies have benefited from the advances in design, execution and analysis since 1950s. These advances include more rigorous selection and matching of case and control population, improved interviewing techniques, location of the design within a general framework of epidemiologic strategies for relating exposure to disease, understanding of the measures of effect, and application of increasingly sophisticated statistical procedures to findings. This review traces the development and future perspectives of the case-control design to assessing cancer etiology. With illustrations drawn primarily from the literature on its use and the value of its results to unravelling the etiology of malignant diseases, we tried to explore if the case-control approach firmly ensconced in epidemiology as investigational tool and rivals in importance the more straightforward cohort approach.

Survival of Campylobacter jejuni in chicken meat, chicken skin and chicken liver at low temperatures

The aim of this study was to determine survival of Campylobacter jejuni (C. jejuni) in chicken meat, chicken skin medallions and chicken liver contaminated with this bacterium at +4 °C and -20 °C, after 24 hours of incubation. The survival of C. jejuni at +4 °C, -20 °C in chicken meat, chicken skin medallions and chicken liver were examined after 24 hours of incubation with C. jejuni. All samples were previously tested for the presence of Campylobacter species according to ISO 10272-1:2006. After 24 hours of incubation at +4 ° C, the number of survived C. jejuni in chicken meat slightly decreased on both non-selective and selective plates, but still in range of 10. After 24 hours of incubation at -20 ° C, the number of survived C. jejuni in chicken meat was in range of 10 cfu/ml on non-selective plate, with complete absence of growth on selective plate. After 24 hours of incubation, the number of survived C. jejuni in chicken liver increased on selective and non-selective plates (>10) at +4 ° C, while at -20 ° C there were no C. jejuni survived on both plates. 24 hours of incubation at both temperatures did not much influence the number of C. jejuni in chicken meet, while chicken skin medaillons allowed increase of the number of bacteria. Incubation of chicken liver at + 4° C allowed bacterial multiplication, while incubation at -20 ° C caused absence of survival (Tab. 1, Ref. 12).

Breast cancer in women under 40 years of age

PURPOSE

It is widely believed that breast cancer in young women is characterized by a relatively unfavorable prognosis and unusual pathological features. The aim of this study was to investigate clinicopathological and biological characteristics in young patients with breast cancer.

METHODS

The study enrolled 1029 consecutive female breast cancer patients who were admitted to the Clinical Centre Nis between July 2002 and December 2008.

RESULTS

91 (8.8%) patients were under and 938 (91.2%) were over 40 years. The mean age was 35.9 years for those under 40 years and 58.3 for those older than 40 years. In both patient groups, left breast was most commonly involved; the most common primary tumor site was the upper lateral quadrant; the most common histological type was ductal carcinoma; histological and nuclear grade 2 was most common. In the younger group of patients, the proportion of patients with T3 and T4 disease was higher (13.0 vs. 9.3% and 16.5 vs. 12.0%), the number of patients with histological and nuclear grade 3 disease was higher (27.5 vs. 24.7% and 37.4 vs. 33.2%), the proportion of patients with 4-9 and >10 positive lymph nodes was higher (22.6 vs. 18.3% and 7.1 vs. 4.0%), and the percentage of family history of breast cancer was higher (5.5 vs. 3.1%), without statistically significant differences between the two age groups. Patients in the younger age group exhibited higher estrogen (ER)/progesterone (PR) receptor negativity (32.6 vs. 24.4%) (p<0.05).

CONCLUSION

Although uncommon, breast cancer in young women is worth special attention. The underlying causes of the disease must be investigated in large population- based studies in the future.

Effects of anthocyanins and anthocyanin-rich extracts on the risk for cancers of the gastrointestinal tract

Anthocyanins are the largest group of water-soluble pigments in the plant kingdom. Anthocyanins are responsible for most of the red, blue, and purple colors of fruits, vegetables, flowers, and other plant tissues or products. In recent years, numerous studies have shown that anthocyanins display a wide range of biological activities. This review summarises recent literature evidence on the association of anthocyanins and anthocyanin-rich extracts consumption with the risk for gastrointestinal tract cancer, concentrating on the results from in vivo animal model tumor systems, as well as data from human epidemiological studies. Potential cancer chemopreventive activities of anthocyanins were revealed from in vitro studies. In vivo animal model tumor systems showed that dietary anthocyanins inhibit cancers of the gastrointestinal tract. Some epidemiological studies have revealed protective effects of anthocyanins consumption on gastrointestinal cancer risk in humans. Pharmacokinetic data indicate that absorption of anthocyanins into the bloodstream of rodents and humans is minimal, suggesting that they may have little efficacy in tissues other than the gastrointestinal tract and skin. Future studies should be undertaken to determine if the anticancer effects of anthocyanins are due to the parent compounds and/or to their metabolites.

Clinical and biological characteristics of breast cancer

PURPOSE

in view of the crucial importance of early detection and diagnosis of breast cancer for subsequent treatment and prognosis, the aim of this study was to identify clinical and biological characteristics of breast cancer at the time of diagnosis.

METHODS

the study enrolled 449 breast cancer patients in Clinical Centre Nis. Results were analyzed using Student's t-test for paired and unpaired samples, chi-square test, Mantel- Haenszel test and Fisher's test of exact probability.

RESULTS

The average patient age was 56.2 ± 12 years (range 23-85). Seventyhorbar;three percent of the affected women were postmenopausal and 8.3% below 40 years of age. Operable disease was identified in 78% of the cases, and metastatic in 3.6%. TNM clinical stage IIA was identified in 27.6% of the patients, T2 in 49.2% and Tis in 0.9%. Almost 44% had negative axillary lymph nodes. Most common monolocalization of metastatic disease was the liver and the supraclavicular lymph nodes, and combined localization was the liver and bones. Histologic and nuclear grades 2 and ductal carcinoma were most common. Estrogen receptor positive (ER+) status was 3-fold higher than ER negative (ER-) status. Human epidermal growth factor receptor 2 (HER2) positive patients were most commonly ER-. The most common primary tumor site was the upper lateral quadrant. Left breast was more commonly involved. Radical surgery was the most common type of operation.

CONCLUSION

in view of the unfavorable age of patients at the time of diagnosis and clinical and biological tumor characteristics, the results confirmed that it is of vital importance to provide breast cancer prevention, screening, and to organize breast cancer units according EUSOMA guidelines.

Hormone sensitivity of primary breast carcinoma

PURPOSE

This study was designed to evaluate hormonal sensitivity of primary breast cancer by way of determination of estrogen receptors (ER) and progesterone receptors (PR) status as an important prognostic and predictive parameter of breast cancer.

METHODS

The study enrolled 449 breast cancer patients surgically treated at the Surgical Clinic Nis, in a period covering 3 years, who continued treatment at the Clinic of Oncology, Clinical Centre Nis. All of the patients were divided into 4 groups depending on the positive or negative status of ER and PR, and 2 subgroups, those with positive or negative HER2 status. Standard descriptive statistical parameters were calculated and several types of tests were applied: Student's t-test for paired and unpaired samples, chi-square test, Mantel- Haenszel test, Fisher's test of exact probability and binary logistic regression model.

RESULTS

The level of ER and PR status positively correlated with patient age, postmenopausal status, lower clinical stage, lower histologic grade (HG) and nuclear grade (NG) and better prognosis. Amplification/overexpression of HER2 positively correlated with premenopausal status and ER negative breast cancer phenotype. According to the model of binary logistic regression, clinical stage and NG of the breast primary were significantly associated with hormonal sensitivity of the tumor.

CONCLUSION

Measurements of receptor macromolecules in clinical oncology is very important, especially in breast cancer patients. ER and PR analysis is an integral part of breast cancer study since it can provide information essential for both treatment and prognosis.

Risk factors for breast cancer: a hospital-based case-control study

PURPOSE

The factors responsible for the genesis of breast cancer remain unclear. A case-control study was undertaken to investigate the possibility of an association between hypothesized risk factors and the development of breast cancer in Serbia.

PATIENTS AND METHODS

This hospital-based case-control study comprised 120 new breast cancer cases and 120 hospital controls matched with respect to age (+/- 2 years). This study used a targeted and detailed questionnaire to obtain information from respondents. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated from multivariate conditional logistic regression models.

RESULTS

Five independent predictors of breast cancer were: delayed age at first birth (OR=6.1, 95% CI=4.2-12.4), alcohol consumption (OR=4.8, 95% CI=1.9-12.4), family history of breast cancer in 2nd degree relatives (OR=2.5, 95% CI=1.4-4.3), never having breastfed (OR=5.2, 95% CI=1.4-18.5) and maternal death in childhood (OR=3.3, 95% CI=1.2-8.6).

CONCLUSION

The results of this study confirmed that the aetiology of breast cancer in Serbia, as elsewhere, is complex. More research is needed to understand the interactions between factors that could affect vulnerability to breast cancer.

Suicide in the elderly 60 years of age and over in the south-east part of Serbia

Some previous investigations indicated that economic crisis (inflation in Serbia 1993/94) have great influence on increasing suicide rates in Serbia. After that suicide decreased, despite the war and bombing in 1999, specially among the elderly people. A total of 453 suicides were registered on the territory of south-eastern Serbia during 1995-2001 years. Of them 295 (65.1%) were aged over 60 years. Generally linear trends of suicide among both genders from 1995 to 2001 decreased, but the slope of decreasing was grater among males than among females. The highest rates among the both genders were registered in the years with the maximum number of suicides, but the linear trends of rates have statistically important correlation with time (r>0.5). Average annual suicide rate among males was 42.5, and among women it was 18.7. The highest average annual suicide rate among men was observed in the age group 75 years and over (93.3), and the lowest in the age group 65-69 (20.6). Among males, in the all age group linear trends of suicide rates decreased, with the highest slope among 75 years and over and the lowest among 65-69 years. The highest suicide rate among females was registered in age group 75 years and over (25.6), the lowest in the age group 65-69 (13.5). The linear trends are similar as among males: downward trend was observed among all aged groups, with the highest slope among women 75 years and over. The most common way of suicide among men was hanging up (63%), poisoning and by firearms. There were no statistical differences between way of suicide and age groups. The most frequent way of suicide among females was hanging up (55%), poisoning (25%) and drowning (12%). There were statistically significant differences in drowning between age groups, 70-74 and 75 and over (p<0.05), and between poisoning and age groups 60-64 years and 75 years and over. Poisoning and drowning are statistically more frequent among women than among men.