Macrolide resistance in Mannheimia haemolytica isolates associated with bovine respiratory disease from the German national resistance monitoring program GERM-Vet 2009 to 2020

Data collected from the German national resistance monitoring program GERM-Vet showed slowly increasing prevalence of macrolide resistance among bovine respiratory disease (BRD)-associated Pasteurellacae from cattle over the last decade. The focus of this study was to analyze the genetic basis of antimicrobial resistance (AMR) and the prevalence of multidrug-resistance (MDR)-mediating integrative and conjugative elements (ICEs) in 13 German BRD-associated Mannheimia haemolytica isolates collected between 2009 and 2020 via whole-genome sequencing. Antimicrobial susceptibility testing (AST) was performed via broth microdilution according to the recommendations of the Clinical and Laboratory Standards Institute for the macrolides erythromycin, tilmicosin, tulathromycin, gamithromycin, tildipirosin, and tylosin as well as 25 other antimicrobial agents. All isolates either had elevated MICs or were resistant to at least one of the macrolides tested. Analysis of whole-genome sequences obtained by hybrid assembly of Illumina MiSeq and Oxford Nanopore MinION reads revealed the presence of seven novel Tn7406-like ICEs, designated Tn7694, and Tn7724- Tn7729. These ICEs harbored the antimicrobial resistance genes erm(T), mef (C), mph(G), floR, catA3, aad(3")(9), aph(3')-Ia, aac(3)-IIa, strA, strB, tet(Y), and sul2 in different combinations. In addition, mutational changes conferring resistance to macrolides, nalidixic acid or streptomycin, respectively, were detected among the M. haemolytica isolates. In addition, four isolates carried a 4,613-bp plasmid with the β-lactamase gene blaROB - 1. The detection of the macrolide resistance genes erm(T), mef (C), and mph(G) together with other resistance genes on MDR-mediating ICEs in bovine M. haemolytica may explain the occurrence of therapeutic failure when treating BRD with regularly used antimicrobial agents, such as phenicols, penicillins, tetracyclines, or macrolides. Finally, pathogen identification and subsequent AST is essential to ensure the efficacy of the antimicrobial agents applied to control BRD in cattle.

P972 Quantitative methods for assessing contractile reserve in patients with diastolic heart failure

Aim

The effectiveness of isometric handgrip exercise on changes of cardiovascular hemodynamics parameter in patients with diastolic heart failure is unknown. We assessed the effect of several hemodynamic parameters and it changes during handgrip maneuvers in patients with different stages of diastolic heart failure during chemotherapy and their improvements after 4 months follow up (4mFU) treatment with single pill combination of ACE inhibitor ACE) and beta –blocker(BB) .Methods: The study population included 65 patients- female / mean age of 45 ± 12 years/ 55 with breast cancer and undergoing chemotherapy / 30 pts with HFpEF and 25 pts with HFmrEF / and 10 pts with HFnEF and without chemotherapy.The effect of handgrip maneuver on hemodynamic parameters were studied by speckle tracking echocardiography. Following maximal squeeze by 100%, during the next 3 minutes patients were instructed to apply pressure at 50%. The global longitudinal strain were extracted by 3, 4 and 2 chamber apical view images on 70-85 fr/s and MAP and HR were performed at basal level, 1st, 2nd and 3rd minutes during handgrip stress test. The contractility /force/ of LV were also calculate as ratio SBP / ESV . Patients with HFmrEF and HFpEF received for 4 months treatment with single pill combination ACE (perindorpril)/ BB (bisoprolol) 5/5 mg.Results:Heart rate(HR) and mean arterial pressure(MAP) increased significantly after handgrip maneuver / from 75 ±6 beats /min to 101 ±12 beats/ min, 109 ± 15 mmHg to 118 ± 19mmHg, p < 0,05 / .Pulmonary artery systolic(s) and diastolic (d) pressure(PAP),pulmonary capillary wedge pressure (PCWP) , cardiac index(CI) , LVEF did not change significantly(p > 0,5) after handgrip maneuvers . On the other hand, LV force (SBP/ ESV ratio) ,MAP and HR decreases significantly (p < 0,01) in group with HFmrEF. In same group were found significantly decreased GLVLS at 2nd and 3rd minutes during stress- test comparable with other 2 groups with HFpEF and HFnEF. After 4mFU and treatment with 5/5 mg doses combination of ACE / BB were found improvement in parameters: HR /p < 0,001/, MAP /p < 0.01/ and contractile reserve as well as LV force /p < 0, 01/ and GLVLS /p < 0,001/.Conclusion: Cardiovascular response to handgrip maneuver may be a marker of failure to respond to compensatory mechanisms. Patients with good LV reserve had a rise in stroke –work with little or no change in LVEDP. Patients with poor contractile reserve had a fall in stroke- work reserve together with a substantial rise in LVEDP. It is concluded that the stress imposed by sustained handgrip provides a simple test for evaluation of LV contractile reserve in patients, who will develop cardiotoxicity during chemotherapy treatment. The treatment with combination with small doses ACE/BB is a big challenge in patients with HFmrEF and HFpEF to improve the contractile reserve.

Occupational and personal risk factors for musculo-skeletal disorders in fertilizer plant workers

The aim of this study was to evaluate the impact of some personal and work-related risk factors for the occurrence and development of MSDs as well as to assess the prevalence and relative risk by means of odds ratio and 95% confidence interval.

SUBJECTS

Of this comprehensive cross-sectional study were 921 workers and employees from the four main departments of the plant. The following complex of methods was applied: personal anamnesis, occupational history, physical examination, clinical laboratory testing, anthropometric examination, conventional radiography and statistical methods.

RESULTS

Age is the first risk factor, discussed by authors. The data showed highly significant differences in the prevalence of MSDs--9.48% in the risk group versus 1.97% in the reference group (OR 5.21, 95% CI 2.42-11.61). Gender is the second risk factor strongly related to MSDs in combination with age. The prevalence of MSDs is higher for women over 40 years that for men over 40 years: OR is 6.43 with 95% CI 1.73-28.23 versus OR 4.66 with 95% CI 1.80-12.77). Obesity is the third risk factor for MSDs. The data showed highly significant differences in the prevalence of MSDs--7.03% in risk group versus 3.08% in reference group, OR 2.38 with 95% CI 1.10-5.30. Smoking for more than 20 years also increases the risk of developing MSDs. At this stage of the research, there is no proof of the impact of hypercholesterolemia, non-occupational or work-related strain on the development of MSDs. The authors' conclusion is that these results may support programs for health promotion and health prevention.

Back disorders (low back pain, cervicobrachial and lumbosacral radicular syndromes) and some related risk factors

The AIM of this study was to estimate the prevalence rates of low back pain (LBP), cervicobrachial and lumbosacral radicular syndromes (CBR and LSRS) in workers from a fertilizer plant and also to analyze the impact of several important work-related and non-occupational risk factors. SUBJECTS of this comprehensive cross-sectional study were 898 workers and employees from the four main departments of the plant. The following complex of methods was applied: neurologic history, complete neurologic status and statistical method.

RESULTS

Age is the first risk factor, discussed by authors. The data showed highly significant differences in the prevalence of CBS-16.2% in the risk group vs. 10.0% in the referent group (OR 1.73, 95% CI 1.14-2.63); LBP-25.8% vs. 17.0% (OR 1.70, 95% CI 1.21-2.38) and LSRS-16.0% vs. 5.8% (OR 3.09, 95% CI 1.89-5.08). Gender is the second risk factor strongly related to LBP, CBS and LSRS. The prevalence of radicular syndromes is higher for women that for men: OR for CBS is 3.27 and 1.93 for LSRS. There is an interesting trend in the case of combined impact of age and gender among men and women of 40 or under and over 40--the risk, estimated by OR, is higher. In men over 40, overweight, obesity and heaviness of smoking, estimated by duration of smoking and daily cigarette consumption (more than 20 years and more than 20 cigarettes per day), increase the risk of developing back disorders (BD). At this stage of the research, there is no proof of the impact of hypercholesterolemia, non-occupational or work-related strain on the development of BD. The authors' CONCLUSION is that these results may support programs for health promotion and health prevention.

[The neurological screening of workers in the manufacture of copper and aluminum rolled wire]

The screening of the nervous system function in 42 workers of copper rolled wire [correction of valzdrat] production and in 34 workers of aluminium rolled wire [correction of valzdrat] production was performed in 1992 and 1993 too; 52 healthy military men were investigated as control group. Target neurological anamnesis, internal and detailed neurological status were carried out. Symptoms of radiculopathy, neurasthenic syndrome and signs of generalized neurovegative dystonia were established in both studies--1992 and 1993. It is suggested that an further detailed investigation (including psychometric tests) is needed to verify of refute the neurotoxic effect of copper and aluminium.

Vibration disease: plasma electrolytes and trace elements

102 patients with vibration disease (mean age 46 +/- 7, length of service in different jobs using vibration tools 17 +/- 7 years) were studied. Plasma electrolytes and trace elements (sodium, potassium, calcium, magnesium, phosphorus, chloride, iron, copper, zinc, cobalt and manganese) and plasma osmolality were investigated, as well as some specific tests indicative of vibration exposure--cold provocation test, vibration sense, thermoasymmetry (left/right hand), skin electric resistance and hand and finger blood flow (Doppler-ultrasound sonometry). In a large number of patients increased values for the following variables were found--magnesium in 43%, zinc in 45%, cobalt in 57%, manganese in 70% and plasma osmolality in 66%. It is suggested that vibration affects mineral metabolism. However, these disturbances in mineral metabolism are secondary to other pathological changes in the body.