Comparison of Mycobacterium avium isolates from Greek AIDS and human immunodeficiency virus-negative patients by pulsed-field gel electrophoresis

Objective To compare the chromosomal types of Mycobacterium avium strains infecting HIV-negative and AIDS patients in Greece.
Methods In total, 41 Mycobacterium avium isolates, 23 from AIDS and 18 from HIV-negative patients, were compared by pulsed-field gel electrophoresis of genomic DNA after Xba I digestion. The majority (87%) of AIDS isolates were from disseminated infection, while the majority (61%) of HIV-negative isolates were from children with cervical lymphadenitis.
Results   Pulsed-field gel electrophoresis classified strains whose electrophoretic patterns were at least 85% similar into three clusters, A (four isolates), B (12 isolates), and C (15), while 10 isolates remained outside of these clusters. There was no statistically significant correlation of any PFGE cluster with a specific patient group. Within each patient group, no significant correlation of PFGE type with time, place of residence or, in the case of AIDS patients, hospital attended was observed.
Conclusions   Genotypic similarities between isolates responsible for disseminated infection in AIDS patients and lymphadenitis in HIV-negative children suggest that related strains, possibly from an environmental source, cause both types of infections.     

Working profiles of dental hygienists in public and private practice in Finland and Norway

Abstract: Aim: The aim was to compare the working profiles of Finnish and Norwegian dental hygienists in public and private practice. To this end, we compared the procedures performed, the type of patients and the time devoted to different tasks. Subjects and methods: A questionnaire survey was originally conducted among a representative sample of dental hygienists in Finland (n = 595) and all authorized dental hygienists in Norway (n = 1 138) in 2004. The questionnaires collected data on the dental hygienists’ age, gender, year of graduation, working experience, work sector (private or public), working time spent on different activities and patient groups. The questionnaire also assessed how frequently the dental hygienists performed 25 different treatment measures. Results: The Norwegian dental hygienists spent 45.4% of their clinical time on check‐ups, whereas the Finns spent 49.9% of their time scaling. Dental hygienists in Finland and Norway working in the public sector spent 42.9% and 74.6% of their working time dealing with children and youth respectively. Conclusions: The working profiles of dental hygienists in Finland and Norway were quite similar, although differences in distribution by activities, type of patients and treatment measures do exist. The main activity of the dental hygienists was clinical work. The most commonly practised clinical activity among Finnish dental hygienists was scaling, and among Norwegians, check‐ups. Public dental hygienists in both countries dealt mainly with children and youths. Oral hygiene instruction was the most commonly reported treatment measure among both Finns and Norwegians.     

Serum osteoprotegerin is a predictor for incident cardiovascular disease and mortality in a general population: the Tromsø Study

Summary. Background: Osteoprotegerin (OPG) concentration in serum is associated with the presence and severity of atherosclerosis. Objective: To investigate the association between serum osteoprotegerin and the risk of a future myocardial infarction, ischemic stroke and mortality in a general population. Patients/methods: OPG was measured in serum collected from 6265 subjects recruited from a general population without a prior myocardial infarction and ischemic stroke (the Tromsø Study). Incident myocardial infarction, ischemic stroke and mortality were registered during follow‐up. Cox regression models were used to estimate crude and adjusted hazard ratios and 95% confidence intervals (HR; 95% CI). Results: There were 575 myocardial infarctions, 284 ischemic strokes and 824 deaths (146 deaths as a result of ischemic heart disease, 78 deaths because of stroke and 600 deaths due to other causes) in the cohort during a median of 10.6 years of follow‐up. Serum OPG (per SD [1.13 ng mL^?1] increase in OPG) was associated with an increased risk of a myocardial infarction (1.20; 1.11–1.31), ischemic stroke (1.32; 1.18–1.47), total mortality (1.34; 1.26–1.42), death because of ischemic heart disease, (1.35; 1.18–1.54), stroke (1.44; 1.19–1.75) and non‐vascular causes (1.31; 1.22–1.41) after adjustment for age, gender, current smoking, systolic blood pressure, body mass index, high density lipoprotein cholesterol, total cholesterol, creatinine, high sensitivity C‐reactive protein (CRP) and diabetes mellitus or HbA1c > 6.1%. No association was detected between OPG and incident hemorrhagic stroke (1.02; 0.73–1.43). Conclusions: Serum OPG was associated with future risk of myocardial infarction, ischemic stroke, total mortality, mortality of ischemic heart disease, stroke and of non‐vascular causes independent of traditional cardiovascular risk factors.     

Platinum chemotherapy for BRCA1-related breast cancer: do we need more evidence?

A recent prospective clinical trial provides further evidence that breast cancers arising in germline BRCA1 mutation carriers are highly sensitive to cisplatin chemotherapy. The potential significance of these data for the management of patients with BRCA1-related and BRCA2-related breast cancer is discussed.In a previous issue of Breast Cancer Research Tomasz Byrski and colleagues present the results of a prospective phase II study of cisplatin in BRCA1-related metastatic breast cancer - that is, breast cancer arising in women with a germline mutation in BRCA1 [1]. They report evidence of substantial efficacy with an overall response rate of 80%, including 45% with complete response, and a time to progression of 12 months. The majority of patients in the study had triple receptor-negative breast cancer, and this time to progression compares favorably with median progression-free survival for triple receptor-negative breast cancer in contemporary series [2]. This study follows on from a retrospective study by the same group that reported a pathological complete response rate of 83% with neoadjuvant cisplatin chemotherapy, compared with a rate of 15% with nonrandomized comparator neoadjuvant chemotherapy [3].The molecular basis for these high response rates is well understood. Both BRCA1 and BRCA2 are required for DNA double-strand break repair by homologous recombination (HR-based DNA repair) [4,5]. Mutations in BRCA1 and BRCA2 inactivate protein function, and in cancer the wild-type allele is almost invariably lost, leading to a defect in HR-based DNA repair in the cancer. Platinum chemotherapy generates interstrand cross-links that can only be adequately repaired by HR-based DNA repair, and consequently BRCA1-deficient and BRCA2-deficient cells are highly sensitive to platinum chemotherapy both in vitro and in vivo. With high response rates in a prospective clinical trial, and a strong biological rationale, it is time to ask whether we are moving towards a new chemotherapy standard for BRCA1-related, and potentially by inference BRCA2-related, breast cancer or whether we need more evidence.The main strength of the current study is that it has been carried out at all. BRCA1 mutations account for a small proportion of patients with advanced breast cancer, even in countries with founder mutations, and this presents a substantial barrier to running studies testing standard chemotherapy. Use of the chemotherapy regimen outside the trial, and the wide availability of novel therapy trials competing for the same patients, add to the challenges of recruiting such trials. Nevertheless, the study by Byrski and colleagues is an open-label single-arm study of only 20 patients, with no central radiological confirmation of response rates, and both this study design and this size make a meaningful interpretation of progression-free survival very difficult. The study was in addition not prospectively registered in a clinical trial registry, removing one of the safeguards against publication bias.The study is dominated by women with three specific mutations in BRCA1 that represent the three founder mutations found in the Polish population [1], with over one-half being the single mutation 5382insC. One of these mutations, C61G, is predicted not to sensitize to cisplatin on the basis of preclinical data [6] yet cancers with this mutation appear to be just as sensitive to cisplatin in the study [1], a discrepancy for which it is important to understand the basis. Prior studies reported by this group have also been drawn from the Polish founder mutations, and we have limited data on the response of cancers with other BRCA1 mutations, and very limited data for BRCA2 mutations.Although the data for BRCA1/2-related breast are therefore relatively limited, there are substantial data on the sensitivity of BRCA1-related and BRCA2-related ovarian cancers to platinum-based chemotherapy [7,8]. BRCA1/2-related serous ovarian cancers are highly sensitive to platinum chemotherapy, and remain sensitive to repeat challenges with platinum chemotherapy, which likely explains the improved survival of BRCA1/2-related serous ovarian cancer compared with BRCA1/2 wild-type serous ovarian cancer [8].Should the accumulation of data, which includes this study by Byrski and colleagues, alter our approach to the treatment of BRCA1-related and BRCA2-related breast cancer? For patients with metastatic BRCA1-related breast cancer, although the data are limited, it seems clear that these patients should be offered the option of platinum-containing chemotherapy at some point during their treatment course. Whether platinum chemotherapy should be used as the first line in preference to other chemotherapy agents is unclear, and this is the subject of the BRCA trial ({"type":"clinical-trial","attrs":{"text":"NCT00321633","term_id":"NCT00321633"}}NCT00321633, {"type":"clinical-trial","attrs":{"text":"NCT00532727","term_id":"NCT00532727"}}NCT00532727) that randomizes first-line patients between carboplatin and docetaxel. For those with BRCA1 mutation-associated triple receptor-negative breast cancer and anthracycline-resistant and taxane-resistant disease, where there are few available active therapies, and the option of platinum-agent chemotherapy seems well founded.Whether the platinum agent should be cisplatin or whether carboplatin would have a similar response rate is unknown. Any difference in efficacy between the two drugs is likely to be small and may be outweighed by logistical and toxicity advantages for the patient. Whether patients with evidence of disease response and a long platinum-free interval (>6 months off chemotherapy) should be retreated with platinum-based chemotherapy on progression or whether they should be treated with alternative chemotherapy regimens remains unclear, and we await data to guide such decisions. Although there are few direct data on BRCA2-related breast cancer, the strength of the biological rational, the comparative data between BRCA1 and BRCA2 in ovarian cancer, and the evidence of poly(ADP ribose) polymerase (PARP) inhibitor efficacy in BRCA2-related breast cancer [9] all suggest that similar advice should apply to BRCA2-related breast cancer.What about the curative setting and patients receiving adjuvant or neoadjuvant chemotherapy? Here the data are less robust. Standard adjuvant anthracycline/taxane chemotherapy cures a substantial proportion of women with breast cancer, with evidence of better outcomes and therapy responses in the BRCA1/2 carrier population [10,11], so changes to this standard should only be made on the basis of strong evidence. At present the data to support platinum agents in this context are limited to retrospective analysis [3] or to prospective data for a very small number of patients [12]. Prospective studies are still required before routine practice changes in the curative setting. The one current exception to this is in the treatment of HER2-positive breast cancer in BRCA1/2 carriers. Relative equipoise has already been shown in the general breast cancer population for the TCH (docetaxel, carboplatin, trastuzumab) regimen compared with standard anthracycline-taxane-trastuzumab-based chemotherapy [13], and the TCH (docetaxel, carboplatin, trastuzumab) regimen presents an attractive option for BRCA1/2 carriers with HER2-positive breast cancer.PARP inhibitors target the same HR-based DNA repair defect as cisplatin chemotherapy, and there is evidence of efficacy for the PARP inhibitor olaparib in BRCA1-related and BRCA2-related breast cancer with substantial prior chemotherapy exposure [9]. PARP inhibitors target the DNA repair defect in a more specific fashion and are well tolerated without typical chemotherapy side effects [9]. The challenge in BRCA1/2-related advanced breast cancer is to develop and support a collaborative mechanism where patients can be identified and entered into randomized trials that test novel therapies such as PARP inhibitors, or mechanistically based chemotherapy, to robustly assess the efficacy relative to standard care, and therefore allow these patients to benefit from these BRCA1/2-focused treatments.     

Anaerobic bacteria in dentoalveolar abscesses

The present study was initiated to determine the bacteriology of 40 orofacial abscesses of dental origin in patients who had taken antibiotics for several days. Bacteria were isolated from all but 2 specimens. Aerobic or facultative anaerobic bacteria were isolated in 21 cases, obligate anaerobic bacteria in 17 cases, whereas in 11 cases, polymicrobial growth was revealed. The average number of bacterial species was 2.1 per specimen. Gram positive aerobic micro-organisms predominated, namely, Staphylococcus epidermidis followed by Streptococci (group A) and Staphylococcus aureus. Among obligate anaerobes, Gram positive micro-organisms, peptostreptococci and peptococci were more often isolated, in the following decreasing order: Ps. productus, Ps. intermedius, Ps. parvulus, Ps. anaerobius, Pc. constellatus, Pc. prevotii. Gram negative anaerobic rods were detected in a small number of cases, namely B. corrodens, B. fragilis, B. melaninogenicus, B. ochraceus, B. oralis. Quantitative determination did not show any meaningful difference between aerobic and anaerobic isolates. Susceptibility tests against a series of antibiotics showed that ampicillin was the most active in aerobes and cefoxitin in anaerobes.     

Use of the Complete Rockall Score and the Forrest Classification to Assess Outcome in Patients with Non-variceal Upper Gastrointestinal Bleeding Subject to After-hours Endoscopy: A Retrospective Cohort Study

Objectives:

To evaluate the usefulness of the Forrest classification and the complete Rockall score with customary cut-off values for assessing the risk of adverse events in patients with upper gastrointestinal bleeding (UGI-B) subject to after-hours emergency oesophago-gastro-duodenoscopy (E-EGD) within six hours after admission.

Methods:

The medical records of patients with non-variceal UGI-B proven by after-hours endoscopy were analysed. For ''high risk'' situations (Forrest stage Ia–IIb/complete Rockall score > 2), univariate analysis was conducted to evaluate odds ratio for reaching the study endpoints (30-day and one-year mortality, re-bleeding, hospital stay ≥ 3 days).

Results:

During the study period (75 months), 86 cases (85 patients) met the inclusion criteria. Patients ''age was 66.36 ± 14.38 years; 60.5% were male. Mean duration of hospital stay was 15.21 ± 19.24 days. Mortality rate was 16.7% (30 days) and 32.9% (one year); 14% of patients re-bled. Univariate analysis of post-endoscopic Rockall score ≥ 2 showed an odds ratio of 6.09 for death within 30 days (p = 0.04). No other significant correlations were found.

Conclusion:

In patients with UGI-B subject to after-hours endoscopy, a ''high-risk'' Rockall score permits an estimation of the risk of death within 30 days but not of re-bleeding. A ''high-risk '' Forrest score is not significantly associated with the study endpoints.     

The influence of scapular depression on upper limb neurodynamic test responses

Objectives

Upper limb neurodynamic testing (ULNT) can be used clinically to assist in identifying neural tissue involvement in patients with upper quarter pain and dysfunction. Consideration for scapular positioning is a crucial component of ULNT standardization, as variations in positioning may dramatically impact sensory and motor responses. This study aimed to determine if there was a meaningful difference in test outcomes when the ULNT was performed in alternative scapular positions.

Methods

This cross-sectional study included 40 asymptomatic individuals. Repeated ULNT testing was performed on the dominant limb with the scapula blocked in neutral (ULNTb) and in scapular depression (ULNTd). Sensory responses, muscle activity, and range of motion outcomes were compared between the two test variations.

Results

Pre-positioning in scapular depression (ULNTd) led to reduced elbow extension range of motion, provoked greater upper trapezius muscle activity and an earlier onset and broader area of sensory responses compared to ULNTb.

Discussion

During ULNTb, the limbs were taken further into range and elicited reduced muscle activation and more localized sensory response providing a less vigorous version of the test. This study demonstrates that scapular positioning has a meaningful impact on ULNT test outcomes in healthy, asymptomatic individuals. The ULNTd can be considered a more vigorous version that may be appropriate when the cervical motions commonly utilized for structural differentiation are limited or contraindicated.     

GES-13, a β-Lactamase Variant Possessing Lys-104 and Asn-170 in Pseudomonas aeruginosa

GES-13 β-lactamase, a novel GES variant possessing Lys-104 and Asn-170, was identified in Pseudomonas aeruginosa. bla_GES-13 was the single gene cassette of a class 1 integron probably located in the chromosome. GES-13 efficiently hydrolyzed broad-spectrum cephalosporins and aztreonam. Imipenem was a potent inhibitor of GES-13 but was not hydrolyzed at measurable rates.GES-type β-lactamases are a distinct branch of class A enzymes of unknown origin. Ten GES variants (GES-1 to -9 and GES-11) differing by one to three amino acid residues have been described (7). bla_GES genes are commonly carried by integrons found in various species, predominantly Pseudomonas aeruginosa and Klebsiella pneumoniae (11). GES β-lactamases all exhibit extended-spectrum properties, hydrolyzing oxyimino-cephalosporins. However, differences in the substrate spectra have been observed. Variants with either Asn (GES-2) or Ser (GES-4, -5, and -6) at Ambler''s position 170 are of special clinical interest since they exhibit increased carbapenemase activity compared to the remaining GES enzymes that possess Gly-170 (1, 12, 15, 16). Substitution of Lys for Glu-104 in various GES enzymes, such as GES-3 and GES-7, may enhance hydrolysis of ceftazidime (3, 14, 17). Notably, GES-4, an enzyme possessing Ser-170, Lys-104, and Thr-62, exhibits significant cefoxitin hydrolysis, in contrast to most GES variants that exhibit either weak activity or are virtually inactive against this substrate (16). Also, a Gly-to-Ser or -Ala substitution at position 243 in GES-9 (9) and GES-11 (6), respectively, confers increased activity against aztreonam. In this report, we describe GES-13, a novel GES variant from P. aeruginosa possessing both Lys-104 and Asn-170.P. aeruginosa NL68 was a bla_GES-positive isolate identified during a screening for acquired carbapenemase genes in multidrug-resistant microorganisms collected during 2007 and 2008 at Evgenidion General Hospital in Athens, Greece. The isolate was considered responsible for a respiratory tract infection in a surgical patient in October 2008. P. aeruginosa NL68 was resistant to penicillins, penicillin-inhibitor combinations, ceftazidime, cefepime, aztreonam, imipenem, and meropenem, as determined by a microdilution technique (Table ​(Table1)1) (2). Disk diffusion tests showed that the isolate was also resistant to fluoroquinolones and aminoglycosides (data not shown).

TABLE 1.

Susceptibilities of GES-type β-lactamase-producing bacterial strains to β-lactam antibiotics