Site Infection Research Articles

Abstract A035: Infection of primary mammary fibroblasts with cytomegalovirus coordinately increases autotaxin-lysophosphatidate-inflammatory signaling, which could increase breast cancer metastasis

Abstract Background: Metastatic breast cancer is the most prevalent cause of mortality by cancer-related deaths in women. Our group showed that the 63% of Canadian breast cancer patients who were infected with CMV were 5.6-times more likely to develop Stage IV cancers with reduced relapse-free survival. Also, the metastatic phenotype of breast tumors and the number and sizes of lung metastases were increased in mice with latent infections. Fibroblasts are important sites of CMV infection. Cancer-associated fibroblasts (CAFs) are also major sites of autotaxin (ATX) secretion in breast tumors, whereas ATX production and CMV infection in breast cancer cells is negligible. ATX produces lysophosphatidate (LPA), which increases inflammatory cytokine production that stimulates further ATX secretion in a feedforward cycle. LPA promotes breast tumor growth and metastasis by signaling through six G protein-coupled receptors. Signaling is terminated by lipid phosphate phosphatases (LPPs)-1 and -3, which degrade LPA and are decreased in breast tumors. Hypothesis: Breast cancer metastasis could be increased by active CMV infection of CAFs through increased inflammation and LPA signaling. Results: Quiescent fibroblasts isolated and cultured from mammary tissue of non-tumor bearing mice (n>3) produced negligible quantities of ATX. LPA signaling was coordinately promoted in these primary fibroblasts infected for 48 h with 1 MOI of mouse CMV (n=3) with a 5-fold increase in mRNA for ATX (p=0.008), increased mRNAs for LPA2,3,4 receptors (p<0.05) and decreased mRNA expressions for LPP1 and LPP3 (p<0.05). An increase in the secretion of granulocyte monocyte-colony stimulating factor of 548 pg/ml (p=0.01) and Interleukin-6 by 8307 pg/ml (p=0.03) was observed post infection (n=5), thus creating a pro-inflammatory environment. Increased mRNA expression of fibroblast markers, including alpha-smooth muscle actin (p=0.005), fibroblast-associated protein (p=0.007), epidermal growth factor receptor (EGFR) (p=0.001) and transforming growth factor- ß receptor 1 (TGF-ßR1) (p=0.03) was also observed post-infection (n=3). The results were analyzed by student’s t-test. Assessment of these factors in breast cancer patients (n=1100) using the Tumor Immune Estimation Resource Analysis showed a positive correlation in the expression of EGFR and TGF-ßR1 with the LPA3,4 receptors (p<0.05). Conclusion: The changes in expression of ATX, LPA receptors and LPPs in CMV- infected fibroblasts are consistent with increased metastasis. Our results show that mCMV infection of primary mammary fibroblasts dramatically reprograms them to express CAF-like properties and promotes ATX-LPA-inflammatory signaling. CAFs are a major constituent of the tumor stroma. They promote tumor progression by secreting factors such as ATX, which increases metastasis, fibrosis and favors immunosuppression. Our results support the use of pharmacological agents to block signaling by the ATX-LPA-inflammatory cycle to treat breast and other cancers, especially for the majority of patients who are infected with CMV. Citation Format: Humayara Khan, Xiaoyun Tang, Frank Wuest, David N. Brindley, Denise G. Hemmings. Infection of primary mammary fibroblasts with cytomegalovirus coordinately increases autotaxin-lysophosphatidate-inflammatory signaling, which could increase breast cancer metastasis [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr A035.

Machine learning-based model for predicting the occurrence and mortality of nonpulmonary sepsis-associated ARDS.

The objective was to establish a machine learning-based model for predicting the occurrence and mortality of nonpulmonary sepsis-associated ARDS. 80% of sepsis patients selected randomly from the MIMIC-IV database, without prior pulmonary conditions and with nonpulmonary infection sites, were used to construct prediction models through machine learning techniques (including K-nearest neighbour, extreme gradient boosting, support vector machine, deep neural network, and decision tree methods). The remaining 20% of patients were utilized to validate the model's accuracy. Additionally, local data were employed for further model validation. A total of 11,409 patients were included, with the most common type of infection being bloodstream infection. A total of 7,632 (66.9%) patients developed nonpulmonary sepsis-associated ARDS (NPS-ARDS). Patients with NPS-ARDS had significantly longer ICU stays (6.2 ± 5.2 days vs. 4.4 ± 3.7 days, p < 0.01) and higher 28-day mortality rates (19.5% vs. 14.9%, p < 0.01). Both internal and external validation demonstrated that the model constructed with the extreme gradient boosting method had high accuracy. In the internal validation, the model predicted NPS-ARDS and mortality in such patients with accuracies of 77.5% and 71.8%, respectively. In the external validation, the model predicted NPS-ARDS and mortality in these patients with accuracies of 78.0% and 81.4%, respectively. The model established via the extreme gradient boosting method can predict the occurrence and mortality of nonpulmonary sepsis-associated ARDS to a certain extent.

Antibiotic-Augmented Chemodynamic Therapy for Treatment of Helicobacter pylori Infection in the Dynamic Stomach Environment.

Helicobacter pylori (H. pylori) is one of the main causes of peptic ulcer disease and gastric cancer. The overuse of antibiotics leads to bacterial drug resistance and disruption to the gut microbiome. Herein, a nanoparticle (TA-FeHMSN@Amox) was developed, comprising amoxicillin (Amox)-loaded iron-engineered hollow mesoporous silica as the core and a metal-polyphenol shell formed by tannic acid (TA) and Fe3+. In acidic stomach conditions, TA-FeHMSN@Amox generates bactericidal ·OH through Fenton/Fenton-like reactions of the degraded product Fe2+ and hydrogen peroxide (H2O2) at the infection site, achieving chemodynamic therapy (CDT). Moreover, released amoxicillin enhances therapeutic efficacy by impeding the self-repair of the bacterial cell wall damaged by CDT, overcoming the limitations of ineffective CDT under conditions lacking sufficient acidity and H2O2. The acidity-responsive CDT combined with reduced antibiotic usage ensures superior in vivo therapeutic efficacy and biocompatibility with intestinal flora, providing a highly potent strategy for treating H. pylori infections in the dynamic stomach environment.

Health care workers hospitalized for COVID-19 in Liberia: who were they, and what were their outcomes?

Background Sustaining a ‘fit-for-purpose’ health workforce requires a better understanding of the health care worker cadres that are affected during pandemics and their outcomes. In hospitalized health care workers with confirmed COVID-19 between March 2020 and May 2023 in Liberia, we determined the hospitalization and case fatality rates, type of health care worker cadres affected, their demographic and clinical characteristics and hospital exit outcomes. Methods This was a cohort study using routine data extracted from hospitalization forms for health care workers in 24 designated COVID-19 treatment facilities. Results Of the 424 health care workers with COVID-19, hospitalization rates progressively declined between 2020 and 2023, (P&lt;0.001) with the highest rates in 2020 (24/1,000 health care workers) and 2021 (14/1,000 health care workers). Case fatality was 2% in both 2020 and 2021 with no deaths thereafter. Among those hospitalized, the highest proportions were nursing cadres with 191(45%), physicians with 63 (15%) and laboratory technicians with 42 (10%). The most frequent reported site for COVID-19 infection was the health facility (326, 89%). COVID-19 vaccination coverage in health care workers was 20%. The majority (91%) of hospitalizations were for mild symptomatic infections. Even in referral centres (n-52), 18 (35%) were for mild infections. Of the 424 who were hospitalized, 412 (97%) recovered, 9 (2%) died and 3 (1%) either left against medical advice or absconded. Of the nine deaths, none were vaccinated, seven had moderate-to-severe disease but were not referred to specialized COVID-19 treatment centers. Conclusions The hospitalized health care workers for COVID-19 were predominantly clinical and laboratory personnel who were mostly unvaccinated, and health facilities were hot-spots for contracting infections. The triage and referral system was weak with unnecessary hospitalization of mild infections. This study provides useful insights for outbreak preparedness including priority vaccination and improving health care worker safety in Liberia.

Spontaneous brain abscess formation: challenge of a shifting pathogen spectrum over the last 21 years - a single center experience.

Spontaneous intracerebral abscess formation is a rare condition presenting with a disabling sequela. The origin of infection can either be primary or secondary to an infection at another location. The site of primary infection - due to the proximity, often the oral cavity, the sinuses, and the orbit - determines the causative pathogens. Treatment often combines surgical and antimicrobial therapies. To determine the microbiology and respective changes and treatment outcome, we performed this retrospective monocentric cohort study of patients requiring surgical treatment of brain abscesses. Patients undergoing surgical treatment of a primary intracranial abscess between January 2000 and January 2021 in the Department of Neurosurgery, Freiburg University Hospital were included. Demographic, clinical and imaging data were extracted from patients' medical records and databases. Treatment approaches were also analyzed, and surgical therapy and antibiotic therapy were reported. Outcome was assessed by the modified Rankin score (mRS) and was dichotomized into good (mRS 0-3) and poor (mRS 4-6) outcome. We included 65 patients with spontaneous intracerebral abscess that were treated with neurosurgical intervention at our institution. Analysis of the causative pathogens showed an increasing dominance of rare pathogens such as fungi, parasites, mycobacteria and anaerobes. Outcome measured by the mRS was similar from 2005 to 2021. The pathogen spectrum of spontaneous intracerebral abscess at our institution is shifting with rarer pathogens being increasingly detected. This retrospective analysis highlights the need for microbiological diagnosis and of combined surgical and antibiological treatment.

Single-cell transcriptomics unveils skin cell specific antifungal immune responses and IL-1Ra- IL-1R immune evasion strategies of emerging fungal pathogen Candida auris.

Candida auris is an emerging multidrug-resistant fungal pathogen that preferentially colonizes and persists in skin tissue, yet the host immune factors that regulate the skin colonization of C. auris in vivo are unknown. In this study, we employed unbiased single-cell transcriptomics of murine skin infected with C. auris to understand the cell type-specific immune response to C. auris. C. auris skin infection results in the accumulation of immune cells such as neutrophils, inflammatory monocytes, macrophages, dendritic cells, T cells, and NK cells at the site of infection. We identified fibroblasts as a major non-immune cell accumulated in the C. auris infected skin tissue. The comprehensive single-cell profiling revealed the transcriptomic signatures in cytokines, chemokines, host receptors (TLRs, C-type lectin receptors, NOD receptors), antimicrobial peptides, and immune signaling pathways in individual immune and non-immune cells during C. auris skin infection. Our analysis revealed that C. auris infection upregulates the expression of the IL-1RN gene (encoding IL-1R antagonist protein) in different cell types. We found IL-1Ra produced by macrophages during C. auris skin infection decreases the killing activity of neutrophils. Furthermore, C. auris uses a unique cell wall mannan outer layer to evade IL-1R-signaling mediated host defense. Collectively, our single-cell RNA seq profiling identified the transcriptomic signatures in immune and non-immune cells during C. auris skin infection. Our results demonstrate the IL-1Ra and IL-1R-mediated immune evasion mechanisms employed by C. auris to persist in the skin. These results enhance our understanding of host defense and immune evasion mechanisms during C. auris skin infection and identify potential targets for novel antifungal therapeutics.

Early prediction of Mycobacterium tuberculosis transmission clusters using supervised learning models.

Identifying individuals with tuberculosis (TB) with a high risk of onward transmission can guide disease prevention and public health strategies. Here, we train classification models to predict the first sampled isolates in Mycobacterium tuberculosis transmission clusters from demographic and disease data. We find that supervised learning, in particular balanced random forests, can be used to develop predictive models to identify people with TB that are more likely associated with TB cluster growth, with good model performance and AUCs of ≥ 0.75. We also identified the most important patient and disease characteristics in the best performing classification model, including host demographics, site of infection, TB lineage, and age at diagnosis. This framework can be used to develop predictive tools for the early assessment of potential cluster growth to prioritise individuals for enhanced follow-up with the aim of reducing transmission chains.

Abstract 4136884: Incidence and Characteristics of Peri-Procedural Complications of Cardiac Implantable Electrical Devices in Breast Cancer Survivors

Introduction: Breast cancer (BC) is the most common non-cutaneous cancer in women. Several BC treatments increase the risk of conduction abnormalities and heart failure, potentially requiring cardiac implantable electrical devices (CIEDs). Due to vascular access devices, surgical management, and chest wall radiation, these patients are subject to upper extremity vascular alterations. There is limited data regarding CIED use in this population. Research question: Do patients with BC and CIEDs have different procedural approaches or complications compared to the general population? Aims: This study aimed to evaluate CIED placement and periprocedural complications in patients with a history of BC. Methods: This was a retrospective study of CIEDs placed at our institution between 2005 and 2023. Patients with a diagnosis of BC prior to time of placement were included. Complications included those within 30 days of the procedure. Results: We analyzed 109 female patients (median age of 73 years, IQR 66-80) who received pacemaker (PPM, 58.7%), cardiac resynchronization therapy defibrillator (CRT-D, 22%), implantable cardioverter defibrillator (ICD, 16.5%), or cardiac resynchronization therapy pacemaker (CRT-P, 2.8%). The median time from cancer diagnosis to device placement was 13 years (IQR 7-21). Oncologic therapies are included in Figure 1. In patients with unilateral cancer, most devices (78.4%) were placed contralaterally, with 32% of all devices being right sided. Anatomy related to chemotherapy port altered intraoperative approach in 2 cases and bilateral lymph node dissection necessitated subcutaneous ICD in 1 case. Complications were noted in 12 patients (11%) and included hematoma, lead revision, upper extremity DVT, pericardial effusion, stress cardiomyopathy, perforation, site infection, and worsening of chronic lymphedema. Conclusions: BC survivors undergoing CIED placement appear to be at higher risk of periprocedural complications when compared to the general population. They are more likely to undergo right sided device placement to avoid vascular access ipsilateral to prior surgery or radiation. Further studies are required to understand the long-term outcomes of CIED placement in this cohort of patients.

The antimicrobial potential of traditional remedies of Indigenous peoples from Canada against MRSA planktonic and biofilm bacteria in wound infection mimetic conditions.

Methicillin-resistant Staphylococcus aureus (MRSA) is the leading cause of wound infections, often progressing into serious invasive bloodstream infections. MRSA disproportionately affects Indigenous peoples in Canada with higher rates of skin and wound infections, an example of persistent gaps in health outcomes between Indigenous and non-Indigenous peoples precipitated by the legacy of colonialism. Conversely, Indigenous peoples have long used natural remedies for infections and other diseases; however, their knowledge was rarely considered for modern medicine. The stagnant antibiotic discovery pipeline and alarming rise of resistance to current antibiotics prompted us to turn to Indigenous medicine as an untapped source of antimicrobials. As such, we collected and prepared 85 extracts of medicinal plants of value to Indigenous peoples spanning the Canadian Prairies. We explored the antimicrobial potential of these extracts against MRSA under wound infection-mimetic conditions compared with culture media typically used to study bacterial antibiotic responses and biofilms but not adequately representative of infection sites. We identified extracts with MRSA growth inhibitory [e.g., bergamot, dock, gaillardia, and dandelion extracts] and biofilm prevention and eradication [e.g., gumweed extracts] activities. Extracts, including those of chokecherry, hoary puccoon, and Northern bedstraw, were only active under wound infection-mimetic conditions, highlighting the benefit of antibiotic discovery under host-relevant conditions. Testing growth inhibitory extracts against an S. aureus cross-resistance platform suggested that they act through mechanisms likely distinct from known antibiotic classes. Together, through an interdisciplinary partnership leveraging Western approaches and traditional Indigenous knowledge, we identified plant extracts with promising antimicrobial potential for drug-resistant MRSA wound infections.IMPORTANCEWe explored the antimicrobial potential of traditional Indigenous remedies against MRSA under wound infection-mimetic conditions. We chose to tackle MRSA wound infections because they constitute an Indigenous health priority, ensuring mutual benefits and reciprocity, which are important principles in partnerships between Indigenous and non-Indigenous researchers. Our partnerships strive to serve as steps towards reconciliation with Indigenous peoples in Canada and a roadmap inspiring similar interdisciplinary collaborations to tackle other healthcare priorities. We identified extracts with promising antibacterial growth inhibitory, biofilm prevention, and eradication activities against MRSA. The antimicrobial potential of some extracts was only observed under wound infection-mimetic conditions, a proof-of-concept that screening under infection-mimetic conditions reveals novel activity undetected under standard conditions. The natural product antimicrobial extracts discovered herein warrant further investigation into their mode of action and chemical composition; they may address the dire need for new antimicrobial and anti-biofilm activity to counter the AMR crisis.

Transformation zone at the vallate papillae: a significant source of papillomavirus infection at the base of the tongue?

The aim of this study was to investigate whether the base of the tongue harbours a transformation zone (TZ), i.e., an initiation site for papillomavirus infection, analogous to that in the uterine cervix by examining the histological structure of Von Ebner's gland ducts in the vallate papillae. Immunohistochemical staining and immunofluorescence techniques were used to detect markers associated with the uterine cervical TZ in the vallate papillae, and these results were compared with those in uterine cervical tissue. Additionally, tongue samples from mouse papillomavirus (MmuPV1)-infected mice were analysed to test our hypothesis. The specific expression of CK17 in the squamous epithelium of the vallate papillae indicated the presence of immature squamous epithelium, arising from the transformation of reserve cells in this region. Moreover, a s determined using virus-infected mice, the TZ at the base of the tongue was a significant site for papilloma virus infection. This is the first study to reveal the presence of a TZ in the vallate papillae, as determined by the presence of reserve cells and immature squamous epithelium, suggesting that the base of the tongue is a significant site for papillomavirus infection. This finding provides an entry point for the early prevention and diagnosis of HPV-associated lesions in the oropharynx.

Zucchini yellow mosaic virus-induced hypersensitive response is associated with pathogenesis-related 1 protein expression and confers resistance in watermelon.

The pathogenesis-related 1 gene of watermelon responds to the infection of ZYMV and contributes to the resistance of its host. Zucchini yellow mosaic virus (ZYMV; family Potyviridae) is a single-stranded positive-sense RNA virus that is a serious threat to cucurbits. Previously, we observed a hypersensitivity response (HR) in the systemic leaves of the 938-16-B watermelon line infected with ZYMV, distinct from the typical HR at infected sites. In this study, we confirmed that ZYMV accumulation in 938-16-B was significantly lower than in the susceptible line H1. Upon inoculation, the entry of ZYMV-eGFP into mesophyll cells is restricted into necrotic spots in leaves, indicating that resistance to ZYMV in 938-16-B is linked to the HR. Further, grafting experiments between 938-16-B and susceptible varieties were performed, and revealed an HR induction in susceptible varieties, suggesting the transfer of resistance signal(s) from 938-16-B to susceptible varieties. Through RNA-sequencing and proteomics analyses of the H1 scions on 938-16-B rootstock, a pathogenesis-related 1 (ClPR1) gene was identified. Specifically, ClPR1 expression is unique to ZYMV-infected 938-16-B. Repression of the expression of ClPR1 prevents an HR in 938-16-B. Conversely, overexpression of ClPR1 in susceptible varieties significantly reduces ZYMV accumulation, but an HR was not induced in susceptible line. Besides the virus, jasmonic acid (JA) can also trigger an HR in 938-16-B. Intriguingly, the expression of ClPR1 (Cla97C02G034020) is induced in both of 938-16-B and H1 by MeJA, rather than salicylic acid. These results suggest that HR is associated with the expression of ClPR1 and contributes to resistance to ZYMV in 938-16-B.

Miniature Robots for Battling Bacterial Infection.

Micro/nanorobots have shown great promise for minimally invasive bacterial infection therapy. However, bacterial infections usually form biofilms inside the body by aggregation and adhesion, preventing antibiotic penetration and increasing the likelihood of recurrence. Moreover, a substantial portion of the infection happens in those hard-to-access regions, making delivery of antibiotics to infected sites or tissues difficult and exacerbating the challenge of addressing bacterial infections. Micro/nanorobots feature exceptional mobility and controllability, are able to deliver drugs to specific sites (targeted delivery), and enhance drug penetration. In particular, the emergence of bioinspired microrobot surface design strategies have provided effective alternatives for treating infections, thereby preventing the possible development of bacterial resistance. In this paper, we review the recent advances in design, mechanism, and actuation modalities of micro/nanorobots with exceptional antimicrobial features, highlighting active therapy strategies for bacterial infections and derived complications at various organs, from the laboratory bench to in vivo applications. The current challenges and future research directions in this field are summarized. Those breakthroughs in micro/nanorobots offer a huge potential for clinical translation for bacterial infection therapy.

Perioperative Management of Takayasu Arteritis for Cardiac Surgery - Review and Single-Center Experience.

Takayasu arteritis (TAK) is classified as a large vessel vasculitis and often causes vascular stenosis, occlusion, and aneurysm formation. Although the principal treatment for TAK involves suppressing inflammation with glucocorticoids, the emergence of biological disease-modifying antirheumatic drugs has considerably changed the treatment landscape of TAK in recent years. Several biological disease-modifying antirheumatic drugs, such as tocilizumab (TCZ), have shown promising effects on TAK in clinical studies. Cardiologists and cardiovascular surgeons encounter patients receiving these drugs who require catheterization, endovascular treatment, or cardiovascular surgery. However, in patients treated with glucocorticoids and TCZ, there needs to be greater awareness of more complications than usual after surgery, such as delayed wound healing, systemic infection, and surgical site infection. In addition, in patients receiving TCZ, inflammatory markers, such as C-reactive protein, may not increase when complications arise from infection. Unfortunately, there are no guidelines or solid evidence that have clearly defined the optimal perioperative treatment strategy for patients with TAK who require cardiovascular surgery. This article reviews the evidence and our recent experience supporting the perioperative use of TCZ, and proposes a protocol that can reduce complications in patients with TAK undergoing invasive cardiovascular treatment.

Oral Administration of Zinc Sulfate with Intramuscular Foot-and-Mouth Disease Vaccine Enhances Mucosal and Systemic Immunity

Background/Objectives: Foot-and-mouth disease (FMD) remains a significant global threat to livestock farming. Current commercial FMD vaccines present several challenges, including the risk of infection and adverse injection site reactions due to oil-based adjuvants. The complex immune environment of the gut-associated lymphoid tissue has the potential to induce broad and diverse immune responses. Therefore, we aimed to explore the potential of zinc sulfate as an oral adjuvant to enhance intestinal mucosal immunity and complement the effects of intramuscular (IM) FMD vaccination. Methods: We conducted serological analyses on mice and pigs, measuring secretory IgA (sIgA) levels and evaluating the expression of mucosal immunity-related genes in pigs. These assessments were used to investigate the systemic and mucosal immune responses induced by oral zinc sulfate administration in combination with an IM FMD vaccine. Results: This combination strategy significantly increased structural protein antibody titers and virus neutralization titers in experimental animals (mice) and target animals (pigs) across early, mid-, and long-term periods. Additionally, this approach enhanced the expression of key cytokines associated with mucosal immunity and increased sIgA levels, which are critical markers of mucosal immunity. Conclusions: Oral zinc sulfate administration may synergize with inactivated FMD vaccines, leading to sustained and enhanced long-term immune responses. This novel strategy could reduce the frequency of required vaccinations or allow for a lower antigen dose in vaccines, effectively stimulating the mucosal immune system and boosting systemic immunity. This approach has the potential to improve the overall efficacy of commercial FMD vaccines.

New insights on extramedullary granulopoiesis and neutrophil heterogeneity in the spleen and its importance in disease.

Neutrophils are traditionally viewed as uncomplicated exterminators that arrive quickly at sites of infection, kill pathogens, and then expire. However, recent studies employing modern transcriptomics coupled with novel imaging modalities have discovered that neutrophils exhibit significant heterogeneity within organs and have complex functional roles ranging from tissue homeostasis to cancer and chronic pathologies. This has revised the view that neutrophils are simplistic butchers, and there has been a resurgent interest in neutrophils. The spleen was described as a granulopoietic organ more than 4 decades ago, and studies indicate that neutrophils are briefly retained in the spleen before returning to circulation after proliferation. Transcriptomic studies have discovered that splenic neutrophils are heterogeneous and distinct compared with those in blood. This suggests that a unique hematopoietic niche exists in the splenic microenvironment, i.e., capable of programming neutrophils in the spleen. During severe systemic inflammation with an increased need of neutrophils, the spleen can adapt by producing neutrophils through emergency granulopoiesis. In this review, we describe the structure and microanatomy of the spleen and examine how cells within the splenic microenvironment help to regulate splenic granulopoiesis. A focus is placed on exploring the increase in splenic granulopoiesis to meet host needs during infection and inflammation. Emerging technologies such as single-cell RNA sequencing, which provide valuable insight into splenic neutrophil development and heterogeneity, are also discussed. Finally, we examine how tumors subvert this natural pathway in the spleen to generate granulocytic suppressor cells to promote tumor growth.

Diabetic Foot Infection: Understanding the Disease its Diagnosis and Prevention

The purpose of this manuscript is to provide a thorough overview of current concepts regarding the evaluation and management of diabetic foot infections. One of the most serious and frequent complications that patients with diabetes mellitus come across is diabetic foot infections. A comprehensive investigation of the literature on diabetic foot infections has been conducted, with a focus on the Diabetes mellitus, pathophysiology, identifiable risk factors, evaluation (including physical examination and laboratory values), treatment approaches, and determining the infection's severity. Preventing severe limb loss and maintaining function are the goals of treating diabetic foot infections. Most diabetic foot infections are caused by polymicrobial organisms. It is probable that a variety of gram-positive and gram-negative aerobes are present at the infection site. Controlling the infection and avoiding more morbidity requires early lesion detection, timely initiation of the proper antibiotic therapy, and surgical excision of necrotic tissue and bone.

Clinical characteristics and bloodstream infection pathogens by gram-negative bacteria in different aged adults: A retrospective study.

This study aims to determine the characteristics and distribution of pathogenic bacteria in bloodstream infections (BSIs) by gram-negative bacteria in adults. One hundred seventy-one adult patients with BSIs who were treated at the Affiliated Hospital of Chengde Medical College between January 2018 and January 2020 were included in this study. The patients were assigned to the young- and middle-aged group and elderly group based on age. General patient data were analyzed. More elderly patients had BSIs and gram-negative bacteria than young- and middle-aged patients. The incidence of underlying diseases in elderly patients was significantly higher than the young- and middle-aged patients (P < .01). The composition of Brucella spp. was significantly different between the elderly group and young- and middle-aged group (P < .05). There were significantly more gallbladder infections in the elderly group than the young- and middle-aged group, and significantly fewer elderly patients had no definite infection sites than the young- and middle-aged group (P < .05). The incidence of complications and in-hospital mortality in the elderly group was higher than the young- and middle-aged group (P < .05). BSIs caused by gram-negative bacteria mainly involved elderly patients. BSIs were characterized by complications and a poor prognosis, as well as pathogenic bacteria and primary infection sites.

The burden and distribution of cystic echinococcosis in Bhutan: a retrospective study.

Cystic echinococcosis (CE), caused by Echinococcus granulosus s.l. is a neglected zoonosis posing a significant public health challenge. Little is known about human CE in Bhutan. This study was conducted to gain an understanding of the burden, distribution, and potential risk factors of CE in Bhutan. From January 2015 to December 2019 data from Jigme Dorji Wangchuck National Referral Hospital (JDWNRH) and 6 other district-level hospitals were reviewed. Descriptive statistics were used to summarize the data. DALYs and Poisson regression models were used to estimate the burden and explore the relationship between cases and possible risk factors. A total of 159 cases were recorded. Most cases (145) were admitted to the surgical ward and 14 cases were referred to India. The average annual incidence was 4.4 cases per 100 000 population. The burden of disease was estimated to be approximately 39 DALYs per year for treatment-seeking cases, or possibly 80 DALYs per year including non-treatment seeking cases. This translates to approximately to 5.2 DALYs and 10.2 per 100 000 per year respectively. The commonest sites of infection were the liver (78%) and lungs (13%). Most cases were treated with surgery (>82%), and more than 47% were admitted to the hospital for >4 days. Policy interventions targeting community engagement, awareness, education, high risk occupational groups, females, and those living in the endemic districts of the central and western regions may yield larger gains. More studies and the institution of a surveillance system can help better guide policy interventions.

Liver cyst penetration of antibiotics at the target site of infection: a randomized pharmacokinetic trial.

The EASL cystic liver disease guideline states that drug penetration at the site of infection (liver cyst) is essential for successful treatment, but pharmacokinetic (PK) data on cyst penetration are limited. This study aims to investigate tissue penetration of four antibiotics in non-infected liver cysts and explores influencing factors. We performed a prospective, randomized single-dose PK-study. Before percutaneous drainage of a non-infected liver cyst, an intravenous (IV) dose of either ciprofloxacin and piperacillin/tazobactam (group 1); or co-trimoxazole (trimethoprim/sulfamethoxazole) and doxycycline (group 2) was given. Cyst fluid was collected during drainage. Blood samples were obtained before, during and after drainage (within 12 h). Drug concentrations were measured with a validated LC-MS/MS. Primary outcome was liver cyst penetration, defined as the cyst-fluid-to-plasma concentration ratio (%) expressed as median (IQR). We included 20 patients, and 21 liver cysts were drained (group 1: n = 11, group 2: n = 10). Median drained cyst volume was 700 mL. Median time between infusion and drainage was 139 min (IQR 120-188 min). Median cyst-fluid-to-plasma concentration ratio was 4.2% (IQR 1.6%-8.9%) for ciprofloxacin, 0.3% (IQR 0.0%-1.3%) for piperacillin, 0.2% (IQR 0.0%-1.3%) for tazobactam, 12.2% (IQR 6.3%-16.1%) for trimethoprim, 0.4% (IQR 0.2%-3.8%) for sulfamethoxazole and 1.6% (IQR 0.9%-2.3%) for doxycycline. Time between trimethoprim infusion and cyst drainage was correlated with increased cyst-fluid-to-plasma concentration ratio (P < 0.01). Trimethoprim and ciprofloxacin have the highest penetration ratios amongst antibiotics tested. We found that liver cyst penetration varies widely between drugs after a single IV dose. NTR8499The trial was originally registered in the Netherlands Trial Register (ID: NL7290), which was converted to the International Clinical Trials Registry Platform in 2022.

A Mucous Permeable Local Delivery Strategy Based on Manganese-Enhanced Bacterial Cuproptosis-like Death for Bacterial Pneumonia Treatment.

Bacterial pneumonia is one of the most challenging global infectious diseases with high morbidity and mortality. Considering the antibiotic abuse and resistance of bacterial biofilms, a variety of metal-based materials have been developed. However, due to the high oxygen environment of the lungs, some aerobic infection bacteria have high tolerance to oxygen and ROS, and most of the metal-based materials based on ROS may not achieve good therapeutic effects. Inspired by the sensitivity of cuproptosis to aerobic respiratory cells, we designed a copper composite antibacterial nanoparticle and found that it can effectively induce cuproptosis-like death in the aerobic bacteria of the lungs. To address the challenge of in vivo application of cuproptosis, manganese dioxide was first incorporated to deplete protective glutathione, which can interact with copper and thus hinder the interaction of copper with proteins and assist in antibacterial action through immune enhancement. Cuproptosis-like death also requires a large number of copper ions. To meet this demand, we deliver positively hydrophilic modified composite nanoparticles that effectively penetrate the lung mucus layer directly to the lungs through local administration, and the copper ions are further released rapidly by the acidic environment at the infected site, which can further destroy bacterial biofilms in synergy with manganese. This drug-delivery system can effectively treat pneumonia caused by aerobic bacteria and avoid systemic toxicity that can be caused by large doses of copper.