Effects of extremely low-frequency electromagnetic fields on Helicobacter pylori biofilm.

Current microbiology · 2010 · Mixed · Low evidence

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MixedLow evidencePaper 4404

Study snapshot

PublicationCurrent microbiology · 2010

Study typein_vitro

Reported directionMixed

Evidence ratingLow

Abstract

The aim of this work was to investigate the effects of exposure to extremely low-frequency electromagnetic fields (ELF-EMF) both on biofilm formation and on mature biofilm of Helicobacter pylori. Bacterial cultures and 2-day-old biofilm of H. pylori ATCC 43629 were exposed to ELF-EMF (50 Hz frequency-1 mT intensity) for 2 days to assess their effect on the cell adhesion and on the mature biofilm detachment, respectively. All the exposed cultures and the respective sham exposed controls were studied for: the cell viability status, the cell morphological analysis, the biofilm mass measurement, the genotypic profile, and the luxS and amiA gene expression. The ELF-EMF acted on the bacterial population during the biofilm formation displaying significant differences in cell viability, as well as, in morphotypes measured by the prevalence of spiral forms (58.41%) in respect to the controls (33.14%), whereas, on mature biofilm, no significant differences were found when compared to the controls. The measurement of biofilm cell mass was significantly reduced in exposed cultures in both examined experimental conditions. No changes in DNA patterns were recorded, whereas a modulation in amiA gene expression was detected. An exposure to ELF-EMF of H. pylori biofilm induces phenotypic changes on adhering bacteria and decreases the cell adhesion unbalancing the bacterial population therefore reducing the H. pylori capability to protect itself.

Machine Enhanced Logic

AI evidence extraction

Structured fields below were generated from the paper’s abstract and metadata to make the evidence easier to inspect. Automated extraction may be incomplete or incorrect; verify important details against the original paper.

Study typein_vitro

Effect directionmixed

PopulationHelicobacter pylori (ATCC 43629) cultures and 2-day-old biofilm

Sample sizeNot supplied

ExposureELF · 2 days

Evidence strengthLowConfidence: 78% · Peer reviewed: yes

Main findings

H. pylori cultures and 2-day-old biofilm exposed to ELF-EMF (50 Hz, 1 mT) for 2 days showed significant differences during biofilm formation in cell viability and morphotypes, with a higher prevalence of spiral forms in exposed samples (58.41%) versus controls (33.14%). For mature biofilm, no significant differences were found versus controls. Biofilm cell mass was significantly reduced in exposed cultures in both experimental conditions; no changes in DNA patterns were observed, and amiA gene expression was modulated.

Outcomes measured

Biofilm formation/cell adhesion
Mature biofilm detachment
Cell viability status
Cell morphology/morphotypes (spiral forms prevalence)
Biofilm mass (cell mass measurement)
Genotypic profile/DNA patterns
luxS gene expression
amiA gene expression

Limitations

Sample size not reported in abstract.
In vitro bacterial model; findings may not generalize beyond the experimental system.
Exposure metrics limited to frequency and magnetic flux density (no dosimetry beyond 1 mT reported).

View raw extracted JSON

{
  "study_type": "in_vitro",
  "exposure": {
    "band": "ELF",
    "source": null,
    "frequency_mhz": null,
    "sar_wkg": null,
    "duration": "2 days"
  },
  "population": "Helicobacter pylori (ATCC 43629) cultures and 2-day-old biofilm",
  "sample_size": null,
  "outcomes": [
    "Biofilm formation/cell adhesion",
    "Mature biofilm detachment",
    "Cell viability status",
    "Cell morphology/morphotypes (spiral forms prevalence)",
    "Biofilm mass (cell mass measurement)",
    "Genotypic profile/DNA patterns",
    "luxS gene expression",
    "amiA gene expression"
  ],
  "main_findings": "H. pylori cultures and 2-day-old biofilm exposed to ELF-EMF (50 Hz, 1 mT) for 2 days showed significant differences during biofilm formation in cell viability and morphotypes, with a higher prevalence of spiral forms in exposed samples (58.41%) versus controls (33.14%). For mature biofilm, no significant differences were found versus controls. Biofilm cell mass was significantly reduced in exposed cultures in both experimental conditions; no changes in DNA patterns were observed, and amiA gene expression was modulated.",
  "effect_direction": "mixed",
  "limitations": [
    "Sample size not reported in abstract.",
    "In vitro bacterial model; findings may not generalize beyond the experimental system.",
    "Exposure metrics limited to frequency and magnetic flux density (no dosimetry beyond 1 mT reported)."
  ],
  "evidence_strength": "low",
  "confidence": 0.78,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "extremely low-frequency electromagnetic fields",
    "ELF-EMF",
    "50 Hz",
    "1 mT",
    "Helicobacter pylori",
    "biofilm",
    "cell adhesion",
    "cell viability",
    "morphotypes",
    "amiA",
    "luxS"
  ],
  "suggested_hubs": []
}

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AI-extracted fields are generated from the abstract and metadata and may be incomplete or incorrect. This material is for informational purposes and is not medical advice.

Identifiers and source

DOI: 10.1007/s00284-009-9558-9
PubMed: 20033173

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