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A simple model describing the most significant impact of electromagnetic heating on pathogen-containing aerosols is presented. While the physics of ohmic heating are well understood, the connection between the unsteady temperature increase with net pathogen inactivation in an aerosolized electrolyte solution over a range of frequencies is not clear. The model is composed of two parts: a thermal model of electromagnetic heating of the droplets and a survival model describing the active pathogen population as a function of time. The droplets of saline solution, whose electrical conductivity depends on salt concentration and carrier frequency, are assumed to be small enough so that ambient air flows are sufficient to counter gravity, and the droplets are assumed to be equally spaced. As the droplets move with the ambient air, energy transport is limited to conduction, and within an adiabatic system, the mean spatial mode dominates the thermal transients of the air-droplet system. The kill rate of the pathogen depends on temperature, and the result of our thermal model informs the pathogen population through the Arrhenius kill rate. The model shows strong qualitative agreement with microwave inactivation of MS2 bacteriophages in aerosolized droplets. Inactivation is improved with larger electric field amplitudes, even for small duty cycles. We show that for a range of viruses with known activation energy, the thermal inactivation mechanism is more reliable for viruses with larger activation energy. [ABSTRACT FROM AUTHOR]

Background: Helicobacter pylori cure rates vary in different geographical regions because of differences in hosts as well as in H. pylori strains. Objective: To review systematically all available data in the literature to determine H. pylori eradication rates in The Netherlands. Methods: A search of all published trials on H. pylori eradication therapy performed in The Netherlands was conducted via electronic database search, hand-searching of abstracts from scientific meetings and checking reference lists of pharmaceutical companies. Full papers and abstracts were included. Data on anti-H. pylori therapies were pooled based on duration and combination of drugs. Only triple and quadruple eradication regimens were studied. Dual therapies were excluded, except for ranitidine bismuth citrate-based dual therapies. Results: We analysed 38 study arms, involving 2197 patients. Twenty different pooled regimens were studied with a mean intention-to-treat eradication rate of 83% (range 35-96%). There were no significant differences in the percentage of patients that stopped treatment due to adverse events between the groups. In these pooled regimens only bismuth combined with tetracycline and metronidazole for 1 or 2 weeks was significantly lower in efficacy in metronidazole-resistant strains than in metronidazole-sensitive strains. The prevalence of metronidazole-resistant strains in The Netherlands showed large regional differences (7-50%). Conclusions: A therapy should be tested in a defined population before becoming standard. Several eradication regimens studied in The Netherlands yield acceptable cure rates of 80% or more on an intention-to-treat basis. We advise taking the local prevalence of metronidazole resistance into account when choosing a first-line eradication regimen. [ABSTRACT FROM AUTHOR]

H. pylori infection is a very common infection of the human stomach, related to various diseases such as gastritis, ulcerative disease of the duodenum and stomach, mucosa associated lymphoid tissue lymphomas and gastric cancer. It is generally accepted that the majority of related diseases is curable once H. pylori infection is successfully eradicated. H. pylori eradication will only be achieved after administration of combination therapies including antibiotics and antacids. Resistance to metronidazole and clarithromycin is an emerging problem, leading to impairment of eradication efficacy, irrespective of the regimen administered. Eradication regimens consisting of three or four anti-H. pylori drugs are the most efficacious. Given the easy use and high convenience to the patients and the high efficacy, 1-week proton pump inhibitor (PPI)-triple therapy is preferred as the first-line therapy. Alternatively, bismuth triple therapy or the combination of antacids and bismuth triple therapy can be prescribed; however, these regimens are less convenient to the patients, the course is prolonged or the side effects occur more frequently compared with PPI-triple therapy.

The number of female residents in the Netherlands has steadily increased in recent years. Due to the increased time on waiting lists to enter residency programmes and to the increased duration of training, female residents will be older during their residencies. This will probably result in an increased number of pregnancies during residencies. A questionnaire regarding pregnancy during residency was sent to 191 residents in two university hospitals in the Netherlands. The response rate was 74.3%. Fifty percent of the male and only 19% of the female residents had children. No negative effects of a pregnancy on their training were experienced or anticipated by the residents. However, a negative effect on the functioning of the department was expected. No formal provisions, like replacements were available and many solutions to replace pregnant colleagues depended on the flexibility of the colleagues. The wish to have children was high and equally distributed among male and female residents, 92% and 96%, resp. Given the difficulty to seek a permanent position and to have children after residency, the choice of many female residents will be to have their children during residency. This increase in number of pregnancies requires anticipation of the residency programme directors. They should take the lead in proposing adequate regulations.