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Routine transfusion of Rh(D)-positive RBCs to Rh(D)-negative patients designated as do not resuscitate conserves Rh(D)-negative red blood cell inventory.

BACKGROUND: A minority of blood donors are Rh(D)-negative, and Rh(D)-negative red blood cell (RBC) products are often overutilized. As such, Rh(D)-negative RBCs may be difficult to maintain in blood bank inventory. STUDY DESIGN AND METHODS: We changed our blood bank laboratory policy to approve non-alloimmunized Rh(D)-negative patients to receive Rh(D)-positive RBCs for routine transfusion under defined criteria. Those criteria included Rh(D)-negative males (all ages) and females (aged >50 years) who were designated as do not resuscitate (DNR), either with or without intubation, in the electronic medical record. RESULTS: From August 15, 2024 through August 15, 2025, a total of 204 Rh(D)-negative patients met the above criteria and were approved to receive routine Rh(D)-positive RBC transfusions. Within that group, 23 patients received Rh(D)-positive RBCs. The remaining patients either did not require transfusion or were issued Rh(D)-negative RBC units. Since implementing this practice, a total of 68 Rh(D)-negative units were conserved during this time frame. Notably, 28 of the 68 units (41%) were type O, Rh(D)-negative. DISCUSSION: Rh(D)-positive RBCs can be routinely given to non-alloimmunized Rh(D)-negative patients who are not at risk for developing hemolytic disease of the fetus and newborn (HDFN). By creating clear guidelines for the routine administration of Rh(D)-positive RBCs to patients who are not at risk for HDFN, the inventory of Rh(D)-negative RBC units can be directed to those patients who would most benefit from this limited resource.

Erythrocytes

Reconsidering the definition of triple-negative breast cancer in the immune checkpoint inhibitor era: an optimal cut-off value for hormone receptor percentage of HER2-negative invasive breast cancer.

The optimal cut-off values of estrogen receptor (ER) and progesterone receptor (PgR) expression to define the positivity of ER and PgR have been under discussion for over a decade but remain controversial. The American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) and the St. Gallen International Expert Consensus recommended that breast cancers with ≥1% of ER or PgR expression should be considered hormone receptor (HR)-positive tumors but ER/PR expression of 1% to 10% should be reported as HR-low positive; however, among HER2-negative disease, data on the overall benefit of adjuvant endocrine therapies for patients with HR-low positive disease is limited, resulting in the revisiting of the definition of triple-negative breast cancer (TNBC). Defining HR-low positive disease by better understanding the biology is essential because of the recent advancement of neoadjuvant and adjuvant systemic therapy strategies, including immune checkpoint inhibitors (ICIs) for TNBC. Additionally, identifying who should be treated with adjuvant endocrine therapy, particularly those who have HR-low HER2-negative disease, which is currently treated as TNBC without adjuvant endocrine therapy, is a clinical unmet need. In clinical practice, treating physicians have tailored systemic treatment strategies using other clinical and pathological factors (i.e., age, grade, Ki-67, tumor size, lymph node involvement). There is no universal practice to treat patients with HR-low HER2-negative breast cancer. This review summarized the currently available data to define the clinically relevant optimal cut-off values of ER/PgR in neoadjuvant- and adjuvant-setting. We recommend considering creating a novel category of triple-negative like breast cancer (TN-like BC), which will require a therapeutic strategy different from conventional TNBC.

Humans

Diagnostic Accuracy of a CRISPR-Based Assay in Smear- and Culture-Negative Fungal Keratitis.

IMPORTANCE: Diagnosing fungal keratitis (FK) in patients with negative smear and culture results remains clinically challenging, highlighting the need for alternative diagnostic approaches. OBJECTIVE: To determine the diagnostic accuracy of the clustered regularly interspaced short palindromic repeats (CRISPR)-based Rapid Identification of Mycoses using CRISPR (RID-MyC) assay for detecting FK in patients with negative smear and culture results using in vivo confocal microscopy (IVCM) as the reference standard. DESIGN, SETTING, AND PARTICIPANTS: This prospective diagnostic accuracy study was conducted from December 2024 to March 2025 at Aravind Eye Hospital, a tertiary ophthalmology referral hospital in Coimbatore, India. Consecutive patients clinically suspected to have microbial keratitis with negative smear and culture results were eligible for inclusion. Data were analyzed from March 2025 to June 2025. INTERVENTIONS: All included participants underwent corneal scraping for RID-MyC assay and imaging by IVCM. MAIN OUTCOMES AND MEASURES: The primary outcomes were sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic concordance of the RID-MyC assay compared with IVCM results. RESULTS: Of 245 consecutive patients clinically suspected to have microbial keratitis, 82 were smear negative. After exclusions due to contraindications or positive subsequent cultures, 41 patients with smear- and culture-negative results were ultimately included in the final analysis. Of these 41 patients (mean [SD] age, 51.0 [14.6] years; 21 [51.2%] women), RID-MyC demonstrated sensitivity of 82.1% (95% CI, 63%-94%) and specificity of 76.9% (95% CI, 46%-95%). Positive predictive value was 88.5% (95% CI, 74%-95%) and negative predictive value was 66.7% (95% CI, 46%-82%). Concordance between RID-MyC and IVCM was observed in 33 cases (80.5%). Notably, prior antifungal treatment was most frequent (4 of 5 [80%]) among patients with positive IVCM but negative RID-MyC results. Conversely, all patients (3 of 3 [100%]) with negative IVCM but positive RID-MyC findings had smaller, peripheral, or paracentral lesions. CONCLUSIONS AND RELEVANCE: In this diagnostic study, in patients with smear- and culture-negative FK, the RID-MyC assay showed good diagnostic accuracy comparable with IVCM and was feasible in all cases, including those in whom imaging was not possible. With its rapid turnaround and minimal equipment needs, RID-MyC may serve as a practical adjunct to conventional diagnostics, particularly in high-burden, resource-limited settings where IVCM is unavailable or contraindicated.

Humans

The role of media in reducing and reinforcing stigma: A randomized controlled trial investigating the impact of positive and negative representations of visible difference.

OBJECTIVES: Individuals with visible differences often experience appearance-related stigma and discrimination, reinforced by negative media portrayals. In contrast, positive portrayals may challenge stereotypes and promote acceptance. This study examined whether exposure to positive, negative or neutral images of visible difference influences appearance-related stigma, body appreciation and broad conceptualizations of beauty. It was hypothesized that positive images would decrease stigma and increase body appreciation and broad conceptualizations of beauty, whereas negative images would increase stigma and reduce broad conceptualizations of beauty. DESIGN: An online randomized controlled experiment using a mixed repeated-measures design compared three conditions (positive, negative, neutral) across pre- and post-exposure. METHODS: A sample of 103 adults viewed 10 images of individuals with visible differences presented in one of three conditions: positive (positive captions), negative (villains with visible differences and negative captions) or neutral (without captions). Participants completed pre- and post-measures of appearance-related stigma, body appreciation and broad conceptualizations of beauty. Repeated-measures ANOVAs examined within- and between-group changes. RESULTS: Appearance-related stigma significantly increased in the negative condition, while remaining unchanged in the positive and neutral groups. Body appreciation significantly increased from pre- to post- across all conditions. No significant effects emerged for broad conceptualizations of beauty. CONCLUSIONS: Negative portrayals of visible difference may reinforce stigma, highlighting the need to discourage such depictions in media. While positive exposure did not significantly reduce stigma, viewing images of visible difference increased observers' body appreciation, indicating potential downward social comparison. Future research should explore strategies to strengthen stigma reduction and broaden conceptualizations of beauty.

Humans

How negative sampling shapes the performance of transcription factor binding site prediction models.

MOTIVATION: Transcription factors (TFs) are key players in gene regulation and development, where they activate and repress gene expression through DNA binding. Predicting transcription factor binding sites (TFBSs) has long been an active area of research, with many deep learning methods developed to tackle this problem. These models are often trained on TF ChIP-seq data, which is generally seen as only providing positive samples. The choice of datasets and negative sampling techniques is a critical yet often overlooked aspect of this work. RESULTS: In this study, we investigate the impact of different negative sampling techniques on TFBS prediction performance. We create high-quality test datasets based on ChIP-seq and ATAC-seq data, where true negatives can be identified as positions that are accessible but not bound by the TF in question. We then train models using various negative sampling techniques, including genomic sampling, shuffling, dinucleotide shuffling, neighborhood sampling, and cell line specific sampling, simulating cases where matching ATAC-seq data is not available. Our results show that, generally, metrics calculated on training datasets give inflated performance scores. Of the tested techniques, genomic sampling of negatives based on similarity to the positives performed by far the best, although still not reaching the performance of baseline models trained on high-quality datasets. Models trained on dinucleotide shuffled negatives performed poorly, despite being a common practice in the field. Our findings highlight the importance of carefully selecting negative sampling techniques for TFBS prediction, as they can significantly impact model performance and the interpretation of results. AVAILABILITY AND IMPLEMENTATION: The code used in this study is available at https://github.com/NatanTourne/TFBS-negatives (DOI: 10.5281/zenodo.18007567).

Binding Sites

Detection of Vi-negative Salmonella enterica serovar typhi in the peripheral blood of patients with typhoid fever in the Faisalabad region of Pakistan.

The synthesis and transportation proteins of the Vi capsular polysaccharide of Salmonella enterica serovar Typhi (serovar Typhi) are encoded by the viaB operon, which resides on a 134-kb pathogenicity island known as SPI-7. In recent years, Vi-negative strains of serovar Typhi have been reported in regions where typhoid fever is endemic. However, because Vi negativity can arise during in vitro passage, the clinical significance of Vi-negative serovar Typhi is not clear. To investigate the loss of Vi expression at the genetic level, 60 stored strains of serovar Typhi from the Faisalabad region of Pakistan were analyzed by PCR for the presence of SPI-7 and two genes essential for Vi production: tviA and tviB. Nine of the sixty strains analyzed (15%) tested negative for both tviA and tviB; only two of these strains lacked SPI-7. In order to investigate whether this phenomenon occurred in vivo, blood samples from patients with the clinical symptoms of typhoid fever were also investigated. Of 48 blood samples tested, 42 tested positive by fliC PCR for serovar Typhi; 4 of these were negative for tviA and tviB. Three of these samples tested positive for SPI-7. These results demonstrate that viaB-negative, SPI-7-positive serovar Typhi is naturally occurring and can be detected by PCR in the peripheral blood of typhoid patients in this region. The method described here can be used to monitor the incidence of Vi-negative serovar Typhi in regions where the Vi vaccine is used.

Bacterial Proteins

Hepatitis B virus genome mutations in precore and basal core promoter regions among HBeAg-negative chronic hepatitis B patients with high viral load in Indonesia.

Hepatitis B e antigen (HBeAg) is widely used as a marker for active HBV replication and serves as a surrogate for HBV DNA&#x2009;>&#x2009;200,000 IU/mL to determine eligibility for tenofovir disoproxil fumarate (TDF) prophylaxis to prevent vertical transmission, according to WHO guidelines. However, some HBeAg-negative patients still harbor high viral loads. Mutations in the precore (PC) and basal core promoter (BCP) regions may reduce or abolish HBeAg expression without necessarily suppressing viral replication. Next-generation sequencing (NGS)-based characterization of these mutations remains limited in Indonesia. This study aimed to analyze the mutation prevalence in the BCP and PC regions associated with HBeAg negativity in Indonesian patients. We conducted a cross-sectional study of 32 chronic HBV treatment-na&#xef;ve, unvaccinated patients with HBV DNA&#x2009;>&#x2009;200,000 IU/mL (16 HBeAg-negative, 16 HBeAg-positive) at Cipto Mangunkusumo General Hospital. BCP and PC mutations were analyzed using NGS, classifying mutations as major (mutation frequency index [MFI] &#x2265;20%) or minor (MFI 1-&#x2009;<&#x2009;20%). Associations were analyzed using the Chi-square or Fisher's exact test and p-values were adjusted using the Benjamini-Hochberg procedure. Among 29 major mutation sites, PC mutations A1846T/C and G1896A were more frequent in HBeAg-negative than HBeAg-positive patients (81.3% vs 6.3% and 75.0% vs 12.5%, respectively; all adjusted p&#x2009;=&#x2009;0.019). Combined analysis showed higher mutation frequencies in HBeAg-negative patients (93.8%, 81.3%, and 62.5% for A1846T/C, G1896A, and G1899A, respectively; all adjusted p&#x2009;=&#x2009;0.015). In conclusion, HBeAg-negative patients with high viral loads are strongly associated with PC mutations, particularly G1896A, A1846T/C, and G1899A. These exploratory findings provide regional NGS-based molecular evidence that established PC mutations may contribute to the coexistence of HBeAg negativity and continued high-level HBV replication in Indonesian patients. Larger studies incorporating broader virological and clinical comparison groups are required to determine the clinical significance of these findings.

Humans

TRIM63 Overexpression in FISH-Negative MiTF Family Altered Renal Cell Carcinoma (MiTF RCC).

TFE3 and TFEB break-apart fluorescent in situ hybridization (FISH) assays are the "gold standard" for diagnostic confirmation of microphthalmia-associated transcription factor (MiTF) family-altered renal cell carcinoma (MiTF RCC), which includes TFE3-rearranged RCC and TFEB-altered RCC. However, FISH assays, for multiple reasons, may lead to equivocal or false-negative results, especially in cryptic fusions resulting from intrachromosomal inversions involving 5' partner genes, such as non-POU domain-containing octamer-binding protein (NONO); GRIPI-associated protein 1 (GRIPAP1); RNA-binding motif protein, X chromosome (RBMX); and RNA-binding motif protein 10 (RBM10). When FISH results are negative in cases with strong morphological suspicion of the listed tumor entities, pathologists may recommend targeted RT-PCR or panel-based RNA fusion sequencing for diagnostic confirmation. Our recent RNA in situ hybridization (RNA ISH)-based study demonstrated RNA expression of the tripartite motif containing 63 (TRIM63) to be highly enriched in TFE3-rearranged RCC and TFEB-altered RCC, including 2 FISH false-negative RCC cases harboring RBM10::TFE3 fusion. Based on these observations, we hypothesized that TRIM63 positivity could aid in diagnosing cases that are negative by conventional FISH assay but remain morphologically suspicious, representing an unmet clinical need in this area. We collected 20 RCC cases with morphological suspicion (with equivocal/indeterminate immunohistochemistry panel) of MiTF RCC, which were TRIM63 positive, negative/equivocal for TFE3/TFEB gene rearrangement by FISH, and underwent next-generation sequencing (NGS). On NGS correlation, 14 of 20 (70%) FISH-negative TRIM63-positive tumors harbored an MiTF gene rearrangement. In the remaining 6 cases, we were unable to fully ascertain the MiTF rearrangement status due to the inherent limitation of the NGS panel utilized. The cases with MiTF gene rearrangement include TFE3 rearrangement in 60% (12/20) and TFEB low-level copy gains (with an additional missense mutation in 1 case) in 10% (2/20) of samples. RBM10:TFE3 fusion was seen in 67% (8/12) of TFE3-rearranged RCC in this cohort. TRIM63 RNA ISH assay could aid in identifying cases that harbor TFE3 or TFEB rearrangement associated with false-negative or equivocal TFE3/TFEB FISH results, especially those involving gene fusions with a paracentric Xp11 inversion. Overall, employment of TRIM63 RNA ISH coupled with TFE3/TFEB FISH assays and follow-up genomic interrogation enhanced diagnostic accuracy for patients with MiTF RCC.

Carcinoma, Renal Cell

Unraveling the Role of Mutations Outside the Basal Promoter and Precore Regions in the HBeAg-Negative Stage of Chronic Hepatitis B.

Hepatitis B e antigen (HBeAg) seroconversion is a crucial event in the natural history of chronic hepatitis B virus (HBV) infection, marked by a significant decrease in viral load and the emergence of mutations that suppress HBeAg expression. However, these mutations alone do not fully account for the reduction in viral load. This study investigated the biological features and pathogenic roles of mutations outside the basal core promoter (BCP) and precore regions during the HBeAg-negative stage of chronic infection. Full-length HBV genomes from HBeAg-positive (n&#x2009;=&#x2009;180) and HBeAg-negative (n&#x2009;=&#x2009;328) genotype D datasets were analyzed, revealing significantly higher genomic heterogeneity in HBeAg-negative sequences compared with HBeAg-positive genomes (50.4&#x2009;&#xb1;&#x2009;16.0 vs. 26.6&#x2009;&#xb1;&#x2009;10.5 nucleotide changes per genome). Twenty-six hotspot amino acid mutations associated with the HBeAg-negative stage were identified, with over half located in the Core region. Subsequently, full-length HBV genomes from six HBeAg-negative patient-derived serum samples were obtained by PCR amplification followed by Sanger sequencing. Infectious clones generated from these genomes, each carrying between 21 and 66 amino acid substitutions, were characterized, showing that mutations in this stage differentially affected viral fitness in vitro by up- or downregulating HBV-DNA levels (ranging from 0.2 to 5 times those of the wild-type isolate), modulating capsid assembly, and altering the expression, secretion, and subcellular localization of viral proteins. In conclusion, while mutations in the BCP and precore regions are the primary drivers of HBeAg seroconversion, mutations outside these regions significantly influence HBV biology and potentially contribute to viral pathogenicity, underscoring the complex interplay between host and virus during the HBeAg-negative stage of chronic infection.

Humans

The clinical and electrocardiographic phenotype of patients with genotype-negative long QT syndrome.

BACKGROUND: Long QT syndrome (LQTS) is a genetic heart disease that increases the risk of ventricular arrhythmias and sudden cardia arrest. Despite advances in genetic testing, a small subset of patients with LQTS remain genetically elusive. OBJECTIVE: This study aimed to determine the prevalence and clinical characteristics of patients with a phenotype of LQTS but without a genotype. METHODS: This study aimed to identify phenotype-positive, genotype-negative patients with LQTS seen at Mayo Clinic (2000-2024). Retrospective data included demographics, clinical evaluations, electrocardiograms, and genetic results. Diagnosis adhered to established criteria, and genotype-negative LQTS was defined by the absence of pathogenic variants despite clinical presentation. RESULTS: The study included 1829 patients with LQTS. Of these, 1706 (93%) had pathogenic or likely pathogenic variants, and 95 patients (5%) had upgraded clinical variants of uncertain significance, leaving 32 (1.7%) with negative genetic tests. Among the genotype-negative patients, 17 underwent next-generation sequencing, identifying a genetic cause in 6 cases (0.3% of the total). The mean age at diagnosis for the remaining 26 patients was 25 &#xb1; 15 years, with 76% being women and an average initial corrected QT of 498 &#xb1; 41 ms. Fourteen patients (53%) experienced cardiac events prior to diagnosis, and 11 (44%) received an implantable cardioverter-defibrillator. The mean follow-up period was 8 &#xb1; 7 years. CONCLUSION: Genotype-negative LQTS accounted for < 2% of our cohort, highlighting diagnostic and management challenges. Comprehensive clinical evaluation and advanced genetic testing remain essential for accurate diagnosis and care.

Humans

Years of life lost in patients with a false-negative diagnosis of primary melanoma. A prospective study of the German Central Malignant Melanoma Registry involving 9063 patients over 28 years.

A false-negative diagnosis of cancer can lead to a delay in effective treatment and a poorer prognosis. Here, we use the example of cutaneous melanoma to examine how many years of life are lost after a false-negative diagnosis compared to a primarily correct diagnosis. From 1996 to 2015, 9,063 patients are prospectively registered in the German Central Malignant Melanoma Registry and followed up until December 2023. A false-negative diagnosis is found in 206 (2.3%) patients. The median time to correct diagnosis is 24.0 months. The 10-year recurrence-free survival probabilities are 32.9% for false-negative diagnoses and 76.2% for correct diagnoses (p&#x2009;<&#x2009;0.001). The 10-year melanoma-specific survival probabilities are 62.1% versus 85.0% (p&#x2009;<&#x2009;0.001). On average, each person with an initial false-negative diagnosis loses 8.2 years of life compared to people with a correct diagnosis. This high number of years of life lost raises the question of whether similar results also apply to other types of cancer.

Humans

A chromatin-informed transcriptional regulatory framework to stratify patients and guide therapy selection in triple-negative breast cancer.

Triple-negative breast cancer is an aggressive and heterogeneous breast cancer subtype with few effective targeted therapies and frequent resistance to chemotherapy. Here, we integrate transcriptional regulatory network inference with chromatin accessibility across a large-scale multi-system collection of primary tumors, patient-derived xenografts and model cell lines to quantify transcription factor activity and identify regulators that underpin triple-negative breast cancer identity. This approach prioritizes 94 high-confidence triple-negative breast cancer transcription factors whose activity capture inter-tumor heterogeneity and independently stratify patient outcome across clinical endpoints. Linking transcription factor activity to pharmacogenomic drug sensitivity profiles identifies reproducible drug-transcription factor associations across independent datasets, including NFE2L3 and CBFB activity as predictors of sensitivity to mTOR inhibition, which we validate in everolimus-treated triple-negative breast cancer patient-derived xenograft models. Collectively, we provide a transcriptional and chromatin-informed framework to capture triple-negative breast cancer regulatory state and expand transcription factor guided precision medicine to this breast cancer subtype.

Humans

Computed tomography-guided precision biopsy combined with metagenomic next-generation sequencing for etiological diagnosis in patients with blood culture-negative systemic infections.

ObjectiveTo evaluate the diagnostic efficacy of computed tomography-guided percutaneous biopsy combined with metagenomic next-generation sequencing in patients with blood culture-negative systemic infections and to assess the clinical impact of using this combined strategy for etiological confirmation and guidance of targeted antimicrobial therapy.MethodsThis single-center retrospective observational cohort study enrolled 78 patients who met the Sepsis-3 consensus criteria for suspected systemic infection and had negative conventional microbiological work-ups (at least two sets of blood cultures) between April 2022 and March 2025. All patients underwent computed tomography-guided biopsy of radiologically identified infectious foci, with specimens processed concurrently for conventional culture and metagenomic next-generation sequencing. Diagnostic performance was benchmarked against the final comprehensive clinical diagnosis, and the influence of metagenomic next-generation sequencing findings on antimicrobial therapy modification was analyzed. Sample size calculation, based on a prior study estimating an metagenomic next-generation sequencing detection rate of 85% (&#x3b1;&#x2009;=&#x2009;0.05, &#x3b2;&#x2009;=&#x2009;0.2), indicated a minimum of 68 cases; accordingly, 78 patients were enrolled.ResultsComputed tomography-guided biopsy was technically successful in all 78 patients (100%). The pathogen detection rate of metagenomic next-generation sequencing (91.0%, 71/78) was significantly higher than that of conventional culture (55.1%, 43/78; p&#x2009;<&#x2009;0.001). Using the final clinical diagnosis as the reference standard, metagenomic next-generation sequencing achieved a sensitivity of 94.7% (95% confidence interval: 86.9-98.5), specificity of 100.0% (95% confidence interval: 29.2-100.0), positive predictive value of 100.0% (95% confidence interval: 94.9-100.0), and negative predictive value of 42.9% (95% confidence interval: 9.9-81.6). Among the 35 culture-negative specimens, metagenomic next-generation sequencing established a definitive microbiological diagnosis in 28 cases (80.0%) and detected polymicrobial infections in 11 cases (14.1% of the cohort). Antimicrobial therapy was rationally adjusted based on metagenomic next-generation sequencing results in 69.2% (54/78) of the patients.ConclusionsThe integration of computed tomography-guided precision biopsy with metagenomic next-generation sequencing offers a highly effective diagnostic approach for blood culture-negative systemic infections. This synergistic strategy improves etiological diagnosis by providing high-yield target specimens that enable comprehensive, unbiased pathogen screening, facilitates differentiation between infectious and non-infectious etiologies, and supplies critical evidence for guiding precision antimicrobial therapy. These findings highlight the growing role of interventional radiology in the contemporary framework of precision infectious disease management.

Humans

Total Synthesis and Structural Revision of Rhabdobranin Reveals a Cryptic Gram-Negative Antibiotic.

Gram-negative bacteria present a major clinical challenge but also remain an underexplored source of antibacterial natural products. Resistance-guided genome mining of the entomopathogenic symbiont Xenorhabdus identified the rdb biosynthetic gene cluster, which encodes a putative prodrug antibiotic, pre-rhabdobranin. However, the inability to isolate the proposed active metabolite, rhabdobranin, has prevented direct functional evaluation. Here we report a convergent total synthesis of the proposed structure of pre-rhabdobranin B, which revealed a stereochemical misassignment at the N-terminal arginine residue. Synthesis of both rhabdobranin epimers showed that, although they are nearly indistinguishable by standard analytical methods, inversion at this single stereocenter has a pronounced effect on antibacterial activity. Biological evaluation of the revised rhabdobranin structure revealed potent antibacterial activity against Gram-negative pathogens, including WHO critical-priority carbapenem-resistant Klebsiella pneumoniae. Cellular and biochemical profiling implicated inhibition of protein biosynthesis as its principal antibacterial mechanism. We further show that the GNAT-family acetyltransferase RdbK N-acetylates rhabdobranin, attenuating its activity and establishing a secondary self-resistance mechanism. These findings validate resistance-gene-guided discovery in Gram-negative symbionts as a strategy for uncovering cryptic antibiotics and identify rhabdobranin as a promising scaffold for Gram-negative antibiotic development.

Anti-Bacterial Agents

Negative descriptors in electronic health records of patients with diabetes.

BACKGROUND: Negative descriptors in electronic health records (EHR) contribute to worse health outcomes; studies show they are also more prevalent in EHRs of women and racial minorities and affect downstream research biases. Similar and unique patterns of negative descriptors may also exist in the records of blind patients, including those with diabetic retinopathy. Diabetic retinopathy is a preventable but leading cause of blindness in the US that is disproportionally high among women and racial and ethnic minorities. METHODS: Using EHR from a large medical center, we created "matched" cohorts of patients with a type 2 diabetes-only diagnosis and patients with a diagnosis of diabetic retinopathy. We identified previously used and new, disability and patient-related negative descriptors and assessed patterns of biased language in the EHR, comparing patients by retinopathy diagnosis (yes/no), and changes in patterns of language usage pre- and post- the retinopathy diagnosis. We also assessed differences between patients with type 2 diabetes at the intersection of blindness (ie, retinopathy diagnosis) and self-reported gender and race and ethnicity marginalization. RESULTS: The EHRs of patients with diabetic retinopathy were significantly more likely than those of patients with diabetes-only diagnoses to contain biased language, across queried negative descriptors. The biasing language was consistently more prevalent in EHRs of patients with diabetic retinopathy identifying as women, Black/African Americans and Hispanic compared to White men and more likely to occur following patients' retinopathy diagnosis. CONCLUSIONS: Our study indicates the presence of both disability- and intersectional biases in EHRs. We discuss findings' implications and suggest steps to address them.

Humans

The Impact of Baseline Negative Emotions on Postoperative Quality of Life in Adolescent Idiopathic Scoliosis Patients: A 2-Year Follow-Up Study.

OBJECTIVE: Adolescent idiopathic scoliosis (AIS) is a three-dimensional spinal deformity that develops during puberty without a clear etiology. Beyond physical manifestations, AIS severely impacts adolescents' psychological and social well-being, leading to anxiety, depression, and low self-esteem. While advancements in surgical techniques have enhanced objective outcomes, existing studies on AIS have primarily focused on objective indices, with limited attention to the long-term impact of preoperative negative emotions on patient-reported subjective quality of life. METHODS: This was a retrospective cohort study. A total of 112 eligible AIS patients who underwent posterior spinal correction surgery between April and August 2023 were enrolled. Inclusion criteria included confirmed AIS, completion of 2-year follow-up, and informed consent; exclusion criteria included missing imaging/questionnaire data, comorbid psychiatric/neurological diseases, or prior spinal surgery. Patients were grouped using the Hospital Anxiety and Depression Scale (HADS) administered on admission. Quality of life was assessed preoperatively and 2&#x2009;years postoperatively using the Scoliosis Research Society-22 (SRS-22, evaluating self-image, mental health, pain, function, treatment satisfaction) and Short Form 36 Health Survey (SF-36, assessing 8 physical and mental health dimensions). Statistical analysis was performed via SPSS, using independent t-tests, paired t-tests, Mann-Whitney U test, and chi-square test. p&#x2009;<&#x2009;0.05 was considered significant. RESULTS: There were no significant differences in baseline characteristics (age, gender, BMI, surgical parameters, scoliosis type, preoperative/postoperative Cobb angles) between the two groups (all p&#x2009;>&#x2009;0.05). Preoperatively, SRS-22 and SF-36 scores showed no inter-group differences (all p&#x2009;>&#x2009;0.05). Postoperatively, the Negative Emotion Group had significantly lower scores in SRS-22 mental health (3.9&#x2009;&#xb1;&#x2009;0.3 vs. 4.5&#x2009;&#xb1;&#x2009;0.2) and treatment satisfaction (4.0&#x2009;&#xb1;&#x2009;0.3 vs. 4.6&#x2009;&#xb1;&#x2009;0.7), as well as SF-36 general health (68.6&#x2009;&#xb1;&#x2009;6.4 vs. 79.7&#x2009;&#xb1;&#x2009;13.3), role-emotional (61.3&#x2009;&#xb1;&#x2009;9.3 vs. 70.8&#x2009;&#xb1;&#x2009;9.7), and mental health (61.8&#x2009;&#xb1;&#x2009;14.3 vs. 68.9&#x2009;&#xb1;&#x2009;10.7) (all p&#x2009;<&#x2009;0.05); no inter-group differences were observed in physical function-related dimensions. Both groups showed significant improvements in physical function-related dimensions postoperatively. The Non-Negative Emotion Group also exhibited significant improvements in SRS-22 self-image/pain and SF-36 bodily pain (all p&#x2009;<&#x2009;0.05), while the Negative Emotion Group showed no significant improvements in these dimensions. CONCLUSIONS: Preoperative anxiety and depression do not affect the recovery of physical function in AIS patients after spinal correction surgery but significantly impede improvements in subjective quality of life dimensions, including mental health and treatment satisfaction. These findings highlight the need to integrate psychological assessment and targeted interventions into the perioperative management of AIS. Such a patient-centered approach will help optimize both physical and psychological outcomes, ultimately achieving comprehensive rehabilitation for AIS adolescents.

Humans

scFANCL: Dual contrastive learning with false-negative correction at cell level for single-cell RNA-seq clustering.

BACKGROUND: Single-cell RNA sequencing (scRNA-seq) enables cellular characterization at single-cell resolution. However, its high dimensionality, sparsity, and noise make clustering challenging. Approaches utilizing contrastive learning and data augmentation have been introduced to improve representation quality for scRNA-seq clustering. In particular, dual contrastive frameworks combining instance- and cluster-level objectives can capture both cell-cell similarities and inter-cluster variations. However, existing dual contrastive frameworks focus primarily on discrete cluster boundaries, neglecting the biological continuity inherent in scRNA-seq data. METHODS: We propose scFANCL, a dual contrastive framework designed to capture biological continuity in scRNA data. Rather than treating all non-augmented samples as negatives, scFANCL applies a cosine-similarity-based threshold to exclude cells of the same type from the negative pool, preserving continuous transcriptional relationships among them while maintaining inter-cluster separation. RESULTS: Extensive experiments across seven publicly available scRNA-seq datasets demonstrated that scFANCL achieves competitive clustering performance compared with existing baseline methods, consistently yielding high ARI and NMI scores across datasets of varying size and complexity. Ablation studies further confirmed the contribution of the false negative filtering component, showing measurable improvements over variants without filtering. Downstream analyses further suggest that the learned embeddings may reflect biologically meaningful transcriptional transitions, including continuous differentiation trajectories within related cell types. The source code is available at https://github.com/mjuailab/scFANCL . CONCLUSIONS: scFANCL addresses a key limitation of conventional contrastive learning by applying a cosine-similarity-based threshold to exclude cells of the same type from the negative pool, thereby preserving biological continuity within cell types while maintaining inter-cluster separation. Evaluations across seven benchmark scRNA-seq datasets demonstrate competitive clustering performance, with learned embeddings capturing biologically meaningful transcriptional structure and characteristics of rare cell populations.

Clustering Algorithms

Cefiderocol susceptibility rates in carbapenem-resistant Gram-negative bacteria in a comparative, multicenter surveillance study in China.

BACKGROUND: Cefiderocol is a siderophore cephalosporin with potent, broad spectrum of activity against carbapenem-resistant (CR) Gram-negative bacteria. The objective of this surveillance study was to assess cefiderocol susceptibility in molecularly characterized CR Gram-negative pathogens collected from hospitalized patients across China. METHODS: Susceptibility testing was performed by the broth microdilution method according to Clinical and Laboratory Standards Institute guidelines, using pre-prepared frozen 96-well microtiter Thermo Fisher plates. Susceptibilities to cefiderocol and most comparators were determined by Clinical and Laboratory Standards Institute breakpoints, to tigecycline by US Food and Drug Administration breakpoints, and to colistin by European Committee on Antimicrobial Susceptibility Testing criteria. Carbapenemases were identified by whole-genome sequencing and polymerase chain reaction. RESULTS: Of 149 CR Klebsiella pneumoniae, 95.3% were susceptible to cefiderocol (OXA-48-positive 100% [n = 15]; IMP-positive 100% [n = 9]; KPC-positive 95.4% [n = 108]; NDM-positive 88.2% [n = 17]) and against 103 NDM-positive CR Escherichia coli, cefiderocol susceptibility was 45.6%. Among comparator antibiotics, ceftazidime-avibactam was only active against K. pneumoniae carbapenemase-positive and OXA-48-positive K. pneumoniae isolates. Susceptibilities to tigecycline and colistin were between 22.2% and 97.1% and between 88.2% and 100% across CR Enterobacterales with different carbapenemases, respectively. High cefiderocol susceptibility rates were found for CR Pseudomonas aeruginosa (98.4%), CR Acinetobacter baumannii (99.6%), and Stenotrophomonas maltophilia (99.6%). Among comparator antibiotics, only colistin showed high activity against CR P. aeruginosa (99.2%) and CR A. baumannii (99.2%). CONCLUSIONS: Cefiderocol susceptibility rates were &#x2265;88% against a collection of carbapenemase-positive CR Gram-negative isolates, except for lower susceptibility in NDM-positive CR E. coli isolates. Continuous monitoring of cefiderocol susceptibility is warranted.

Cefiderocol