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Abstract Novel advances in the field of brain imaging have enabled the unprecedented clinical application of various imaging modalities to facilitate disease diagnosis and treatment. Electrical impedance tomography (EIT) is a functional imaging technique that measures the transfer impedances between electrodes on the body surface to estimate the spatial distribution of electrical properties of tissues. EIT offers many advantages over other neuroimaging technologies, which has led to its potential clinical use. This qualitative review provides an overview of the basic principles, algorithms, and system composition of EIT. Recent advances in the field of EIT are discussed in the context of epilepsy, stroke, brain injuries and edema, and other brain diseases. Further, we summarize factors limiting the development of brain EIT and highlight prospects for the field. In epilepsy imaging, there have been advances in EIT imaging depth, from cortical to subcortical regions. In stroke research, a bedside EIT stroke monitoring system has been developed for clinical practice, and data support the role of EIT in multi-modal imaging for diagnosing stroke. Additionally, EIT has been applied to monitor the changes in brain water content associated with cerebral edema, enabling the early identification of brain edema and the evaluation of mannitol dehydration. However, anatomically realistic geometry, inhomogeneity, cranium completeness, anisotropy and skull type, etc., must be considered to improve the accuracy of EIT modeling. Thus, the further establishment of EIT as a mature and routine diagnostic technique will necessitate the accumulation of more supporting evidence.

Background: There are increasing concerns towards the transmission of extended spectrum-β-lactamases (ESBL)-producing Enterobacteriaceae in hospital intensive care units (ICUs) at obstetrics & gynaecology departments. The aim of this study was to determine the clinical characteristics and prevalence of ESBL-producing Escherichia coli (E. coli) and Enterobacter cloacae (E. cloacae) isolates collected from ICUs at obstetrics & gynaecology departments in a tertiary care hospital, China. This study also explored the treatment options for E. coli and E. cloacae infections. Methods: E. coli and E. cloacae isolates from ICU samples were identified by using the Vitek 2 Compact System with the GN and ASTGN13 cards. Antimicrobial susceptibility profiles were determined by using the broth microdilution method. Double-disk synergy test (DDST) was performed to screen for ESBLs and combined with the EDTA-disc synergy to detect the production of carbapenemase. Enterobacterial repetitive intergenic consensus (ERIC)-PCR was applied to investigate the clonality of the isolates. Results: A total of 223 strains isolated from 283 hospitalized patients in the ICU with nosocomial infections between 2017 and 2019 were analyzed. Of these, 104 isolates were classified as E. coli and 103 isolates as E. cloacae by the VITEK GNI system. Of the 207 isolates, 131 (63.3%) were separated from sputum or tracheal secretions. ESBL-screen positive was 45.2% (47/104) for E. coli, and 44.7% (46/103) for E. cloacae. Resistance rates of ESBL-producing E. coli and E. cloacae isolates were 95.5% and 91.3% for ampicillin, respectively; 80.6% and 76.1% for ampicillin/tazobactam; 88.1% and 28.3% for ciprofloxacin; 89.6% and 15.2% for levofloxacin; 34.3% and 45.7% for netilmicin; 82.1% and 41.3% for compound sulfamethoxazole; 20.9% and 43.5% for amikacin; 58.2% and 37.0% for gentamicin; 20.9% and 69.6% for piperacillin/tazobactam. Additionally, all ESBL-producing isolates were fully resistant to cefazolin, cefuroxime, ceftazidime, ceftriaxone, cefepime, and aztreonam. On the other hand, isolates were fully susceptible to imipenem and meropenem. Results of ERIC-PCR in all of ESBL-producing E. coli isolates exhibited 11 distinct patterns with a similarity coefficient of 0.8. Only one distinct ERIC pattern was observed amongst the 46 strains of ESBL-producing E. cloacae. Analysis of ERIC patterns demonstrated that there was an outbreak of nosocomial infection of ESBL-producing E. coli and E. cloacae in obstetrics & gynecology ICU of this hospital. Discussion: Our data indicate that the ESBL-producing E. coli and E. cloacae are circulating in the ICU and constitute a major source infection spread. It is necessary to increase surveillance of infections in the ICU and develop adequate infection prevention strategies.

Background: We investigated the susceptibility patterns and genotype of extended-spectrum-beta-lactamase (ESBL)-producing Klebsiella pneumoniae isolates. Methods: A prospective survey of K. pneumoniae-infected patients was conducted in obstetrics & gynaecology settings in three associated hospitals of a university in China from 2017 to 2019. All isolates were identified as K. pneumoniae by the conventional standard procedures and confirmed by use of the VITEK GNI system. Susceptibility to 16 antimicrobial agents of ESBLs was determined by way of a screening procedure using discs. PCR amplification of bla genes, and sequencing of PCR products were performed to determine their molecular types. Results: A total of 518 of K. pneumoniae were isolated from sputum specimens in three affiliated hospitals. Out of these, 158 strains were ESBL producers and 64 strains were non-ESBL producers from the first hospital; 114 strains were positive for producing ESBLs and 60 strains were negative for ESBLs in the second hospital, and 86 strains were ESBL producer and 36 strains were negative from the third hospital. bla gene contents showed that 88 strains (24.6%) carried the blaT⁢E⁢M-2 gene, and 74 strains (20.1%) contained the blaS⁢H⁢V-3 gene, 44 strains (12.3%) had the blaC⁢T⁢X-M-2 gene, 42 strains (11.7%) had the blaC⁢T⁢X-M-4 gene, 38 strains (10.6%) harboured blaC⁢T⁢X-M-5 and blaC⁢T⁢X-M-8 genes, and 29 (9.5%) strains contained blaC⁢T⁢X-M-15 gene. Also, 20 (5.6%) strains contained blaO⁢X⁢A-1. The co-existence of blaC⁢T⁢X-M-15 and blaS⁢H⁢V-3 was identified in 20 strains (5.6%), 12 strains (3.3%) co-existed with blaS⁢H⁢V-3 and blaT⁢E⁢M-2, 14 isolates (3.9%) harboured blaT⁢E⁢M-2 and blaC⁢T⁢X-M-15, eight isolates (2.2%) possessed blaS⁢H⁢V-3, blaT⁢E⁢M-2, and blaC⁢T⁢X-M-15. Discussion: The high prevalence of ESBLs in K. pneumoniae isolates with diverse enzyme gene types indicated the need for screening the changes in ESBL-producing isolates in this region.

Radiation therapy is a common treatment modality for patients with malignant tumors of the head and neck, chest and axilla. However, radiotherapy inevitably causes damage to normal tissues at the irradiated site, among which damage to the brachial plexus nerve(BP) is a serious adverse effect in patients receiving radiation therapy in the scapular or axillary regions, with clinical manifestations including abnormal sensation, neuropathic pain, and dyskinesia, etc. These adverse effects seriously reduce the living quality of patients and pose obstacles to their prognosis. Therefore, it is important to elucidate the mechanism of radiation induced brachial plexus injury (RIBP) which remains unclear. Current studies have shown that the pathways of radiation-induced BP injury can be divided into two categories: direct injury and indirect injury, and the indirect injury is closely related to the inflammatory response, microvascular damage, cytokine production and other factors causing radiation-induced fibrosis. In this review, we summarize the underlying mechanisms of RIBP occurrence and possible effective methods to prevent and treat RIBP.