For locally advanced rectal cancer,neoadjuvant chemoradiotherapy,followed by surgery and postoperative adjuvant chemotherapy has become a standard treatment mode.Neoadjuvant chemoradiotherapy can induce the tumors to shrink to different extent.Partial patients can obtain complete remission validated by postoperative pathological examination,which contributes to increasing the probability of radical surgery for rectal cancer patients,reducing the recurrence rate and improving the long-term clinical prognosis.In recent years,the prediction and evaluation of the clinical efficacy of neoadjuvant therapy has captivated widespread attentions from clinicians.In terms of imaging methods,conventional morphological imaging techniques cannot accurately assess the clinical efficacy of neoadjuvant chemoradiotherapy,whereas DWI-MRI,DCE-MRI,PET-CT and other functional imaging techniques can not only reflect the degree of tumor shrinkage,but also reveal the changes in the functional metabolism of tumors before and after treatment and yield higher accuracy.In this article,recent application of imaging techniques in the evaluation of clinical efficacy of neoadjuvant chemoradiotherapy for rectal cancer was reviewed.

Objective:To explore the HIV-1 drug resistance in patients with HIV/AIDS in Guilin city following the failure of antiretroviral treatment (ART).Methods:Plasma samples were collected from patients in Guilin who had received ART for more than 1 year and had a HIV viral load greater than or equal to 1 000 copies/ml from January 2019 to December 2023, and demographic information was also collected for HIV-1 genotype subtype analysis and drug resistance testing to determine the resistance mutation loci and the susceptibility of the strains to drugs.Results:A total of 766 patient samples with failed ART collection and successful amplification were collected, of which 536 (69.97%, 536/766) were male, with an average age of 53 years; a total of 8 HIV-1 subtypes were detected, with CRF01_AE (80.55%, 617/766), CRF07_BC (11.10%, 85/766) and CRF08_BC (6.92%, 53/766) predominated. The drug resistance analysis showed that the HIV-1 drug resistance rate was 34.86% (267/766), including nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs) and protease inhibitor (PI), with dual resistance to NRTIs/NNRTIs (48.31%, 129/267) and NNRTIs resistance (43.07%, 115/267) predominantly. A total of 37 resistance mutation sites were detected, 14 NRTIs-associated mutation sites mainly included M184V/I (47.57%, 127/267), K65R (18.73%, 50/267), K70E/N/T/G/R (13.11%, 35/267), etc., and 18 NNRTIs-associated mutation sites mainly included K103 N/R (56.93%, 152/267), V179 D/E/T (21.72%, 58/267), G190C/S/Q (17.23%, 46/267), and V106I/M (16.85%, 45/267), etc.; and 5 PIs-associated mutation sites was the highest with L10V/I mutation rate (3.00%, 8/267).Conclusions:HIV/AIDS patients in Guilin have shown favorable outcomes in antiviral therapy, with a relatively low overall incidence of drug resistance. However, it is essential to enhance surveillance to reduce the spread of drug-resistant strains in the future.