[Application of electrical impedance tomography in pulmonary rehabilitation]

Pulmonary rehabilitation is a comprehensive and individualized intervention for patients suffering from respiratory dysfunction due to various diseases. This approach has been highly valued and implemented by clinical medical professionals. However, the lack of equipment and real-time monitoring of ventilatory lung function during pulmonary rehabilitation treatment is a challenge. In addition, there is a need for improved methods that can directly guide physiotherapists to provide precise treatment. Electrical impedance tomography (EIT) is a novel medical imaging technology that allows real-time monitoring of lung ventilation status. It is currently being translated from basic research into clinical applications and is widely used in respiratory disease, particularly in critical care respiratory management. However, there is a lack of reports on pulmonary rehabilitation guidance and outcome evaluation. This article aimed to provide a comprehensive review of this field, with the aim of generating more ideas for clinical research and further improving individualized treatment in the field of pulmonary rehabilitation.

[A survey on clinical practice of tracheostomy decannulation in medical institutions at all levels across the country]

Objective: A questionnaire survey was conducted on the clinical practice of tracheostomy decannulation among medical staff in medical institutions at all levels across the country. Methods: The questionnaire was determined by literature review and expert consultation to investigate the clinical practice of tracheostomy decannulation among medical staff in comprehensive and rehabilitation hospitals of different levels across the country and the factors considered when deciding to decannulate. Statistical methods used χ² test and one-way ANOVA. Results: A total of 570 questionnaires were collected from all over the country, with 463 valid questionnaires. The survey results showed that the most important factors in clinical practice to determine the decannulation of the tracheostomy tube were upper airway patency, cough effectiveness, level of consciousness and oxygenation. Before decannulation, 220 (47.50%) would choose to change to metal cannula, and 384 (82.90%) would routinely occlude the tube. 294 (63.50%) thought that re-intubation within 24 hours after decannulation of the tracheostomy tube was failure of decannulation. The decannulation failure rate was mostly 2%-5%. Conclusions: Upper airway patency, cough effectiveness, level of consciousness and oxygenation were important factors when considering decannulation. Reintubation within 24 hours of decannulation was defined as failure by the majority of respondents.

Norwalk virus genome cloning and characterization

Major epidemic outbreaks of acute gastroenteritis result from infections with Norwalk or Norwalk-like viruses. Virus purified from stool specimens of volunteers experimentally infected with Norwalk virus was used to construct recombinant complementary DNA (cDNA) and derive clones representing most of the viral genome. The specificity of the clones was shown by their hybridization with post- (but not pre-) infection stool samples from volunteers infected with Norwalk virus and with purified Norwalk virus. A correlation was observed between the appearance of hybridization signals in stool samples and clinical symptoms of acute gastroenteritis in volunteers. Hybridization assays between overlapping clones, restriction enzyme analyses, and partial nucleotide sequence information of the clones indicated that Norwalk virus contains a single-stranded RNA genome of positive sense, with a polyadenylated tail at the 3' end and a size of at least 7.5 kilobases. A consensus amino acid sequence motif typical of viral RNA-dependent RNA polymerases was identified in one of the Norwalk virus clones. The availability of Norwalk-specific cDNA and the new sequence information of the viral genome should permit the development of sensitive diagnostic assays and studies of the molecular biology of the virus.

In situ hybridization for quantitative assay of infectious hepatitis A virus

A method of in situ hybridization using single-stranded RNA probes of opposite polarity for quantitative enumeration of hepatitis A virus (HAV) in infected cells has been developed. Kinetic experiments showed that foci of infected cells appeared as early as day 2 postinfection. The absence of foci in cells examined immediately after virus adsorption indicated that foci detected subsequently were related to viral replication. Foci were detected by hybridization with RNA probes complementary to HAV genomic RNA but not with RNA probes identical to HAV genomic RNA. The number of foci observed was linearly related to the HAV dose inoculated. Focus formation was reduced when a virus inoculum was pretreated with guinea pig anti-HAV hyperimmune serum but not when it was pretreated with preimmune serum. The high resolution of hybridization signals and relative rapidity of the test indicated that this technique will be useful for measuring serum neutralizing antibodies and for quantitative assay of infectious HAV.