Search Results (76)

Cat bites frequently lead to polymicrobial infections due to deep puncture wounds that inoculate oral flora into poorly oxygenated tissues. While Pasteurella multocida is the most commonly implicated organism, environmental and atypical pathogens may also play a role, yet often go unrecognized. This article reports a rare case of polymicrobial septic arthritis caused by a domestic cat bite in an immunocompetent adult, with isolation of Rahnella aquatilis, a freshwater-associated Enterobacterales species not previously reported in this context. A 33-year-old immunocompetent male presented with acute hand swelling, pain, and functional impairment within 24 h of the bite. Emergency surgery revealed purulent tenosynovitis and arthritis. Intraoperative cultures identified R. aquatilis, P. multocida, and Pantoea agglomerans. Identification was performed using MALDI-TOF MS. The R. aquatilis isolate was susceptible to beta-lactams (excluding ampicillin), quinolones, and co-trimoxazole. The patient received amoxicillin–clavulanic acid and fully recovered within two weeks. This is the first reported case of joint infection involving R. aquatilis following a cat bite. It highlights the importance of considering environmental Enterobacterales in animal bite wounds, and the utility of advanced microbiological tools for detecting uncommon pathogens. Broader awareness may improve diagnosis and guide targeted therapy in polymicrobial infections. Full article

Background: Staphylococcus aureus is a significant pathogen causing both local and systemic infections in children, with deep tissue involvement leading to severe complications. This study aimed to assess clinical manifestations and identify risk factors for deep tissue involvement in pediatric S. aureus infections. Methods: All children between 1 month and 18 years who had S. aureus growth in blood, pus, or joint fluid culture were included. Results: A total of 61 patients (median age 55 months) were included, with 22.9% having deep tissue infections. Osteoarticular infections, pyomyositis, and pulmonary involvement were common. Deep-seated infections were significantly associated with community-acquired infections and positive hemocultures after 72 h (p < 0.01). Laboratory results showed significantly higher levels of C-reactive protein, sedimentation rate, D-dimer, and fibrinogen in the group with deep-seated infections (p = 0.02, p = 0.018, p = 0.01, and p = 0.015, respectively). The decision tree model showed that the first indicator of deep-seated infection was a D-dimer level above 1.15 mg/L, followed by a fibrinogen level above 334 mg/dL. Conclusions: Deep-seated S. aureus infections are more frequently associated with community-acquired cases, persistent hemoculture positivity, and methicillin-susceptible Staphylococcus aureus (MSSA) strains. Additionally, elevated D-dimer and fibrinogen levels may serve as valuable markers for identifying deep-seated infections in pediatric patients. Full article

As potable water becomes limited, alternative water sources, such as reclaimed wastewater, for crop irrigation have gained attention. However, reclaimed wastewater for irrigation may expose edible crops to compounds of emerging concern (CECs), which may include pharmaceutics, hazardous waste, and volatile substances. Of these CECs, carbamazepine (CBZ) is of particular interest because only 7% of CBZ is filtered out during traditional wastewater treatment processing methods. Two trials were designed to evaluate the uptake and partitioning of CBZ in lettuce grown in a deep-water culture system (DWC) at low and high concentrations. The first trial (0 µg L⁻¹, 12.5 µg L⁻¹, 25 µg L⁻¹, and 50 µg L⁻¹) of CBZ had few effects on lettuce (Lactuca sativa var. capitata) growth, and low concentrations of accumulated CBZ were found in lettuce tissues. As a result, increased concentrations of CBZ were used in the second trial (0 mg L⁻¹, 21 mg L⁻¹, 41 mg L⁻¹, and 83 mg L⁻¹). Greater amounts of CBZ accumulated in plant tissues and the application of higher rates of CBZ negatively affected the growth and overall health of the lettuce. Further research is needed to determine the impacts of CECs on plant uptake and growth, as well as the environmental conditions. Full article

Background: Diabetic foot osteomyelitis (DFO) is a serious complication of diabetic foot ulcers (DFUs) that contributes to high morbidity and an increased risk of lower extremity amputation. While bone biopsy cultures are considered the gold standard for identifying causative pathogens, their invasive nature limits widespread clinical use. This study evaluates the microbiological concordance between deep tissue and bone cultures in diagnosing DFO. Methods: A retrospective analysis was conducted on 107 patients with DFO who underwent simultaneous deep tissue and bone biopsy cultures. Patient demographics, ulcer classification, and microbiological culture results were recorded. The agreement between deep tissue and bone cultures was assessed to determine the diagnostic utility of deep tissue sampling. Results: The overall concordance between deep tissue and bone cultures was 51.8%. Staphylococcus aureus was the most frequently isolated pathogen in both culture types and had the highest agreement rate (44.4%). Concordance rates were lower for Gram-negative bacteria (31.9%) and other Gram-positive microorganisms (24.2%). In 21.2% of the cases, pathogens were isolated only from deep tissue cultures, while 16.5% had positive bone cultures but negative deep tissue cultures. Conclusions: Deep tissue cultures demonstrate moderate microbiological concordance with bone biopsy in the diagnosis of DFO, particularly in cases with monomicrobial Staphylococcus aureus infection. While bone biopsy remains the gold standard, deep tissue cultures may be a practical alternative when bone sampling is not feasible or for patients unsuitable for surgery. However, their limited reliability in detecting Gram-negative and polymicrobial infections underscores the need for more accurate, less invasive diagnostic tools. Future research should focus on validating molecular and advanced diagnostic methods to improve clinical decision-making and patient outcomes in DFO. Full article

Background/Objectives: Despite the introduction of innovative therapeutics, lung cancer is still the leading cause of cancer-related death. For this reason, lung cancer still requires deep characterization to identify cellular and molecular targets that can be used to develop novel therapeutic strategies. Three-dimensional cellular models, including patient-derived organoids (PDOs), represent useful tools to study lung cancer biology and may be employed in the future as predictive tools in therapeutic decisions. However, the successful establishment of lung cancer organoids cultures that faithfully represent the respective patient tissues is still challenging due to low success rate and/or overgrowth of normal airway epithelial cells. Methods: We set up a two-step protocol that allows for establishing both short-term and long-term 3D cultures, with different characteristics and success rates. Results: Cancer tissue-originated spheroids (CTOSs) show a 100% success rate and allow for the concomitant isolation of autologous tumor infiltrating leukocytes (TILs). On the contrary, PDOs can be expanded for a medium-long term and bio-banked but retain a lower success rate and the possibility of contamination with normal airway epithelial cells. To overcome these problems, we set up an optimal medium formulation and we implemented rigorous quality controls, leading to a substantial improvement in the success rate of tumoral PDO establishment. Conclusions: Overall, this protocol guarantees flexibility and reliability, also providing useful guidelines for quality control checks to support different experimental settings. The setting up of a robust protocol for lung cancer PDO culture establishment and expansion is a key requirement for their employment both in cancer research and as predictive tools in clinical practice. Full article

Nuclear protein delivery underlies an array of biotechnological and therapeutic applications. While many variations of protein delivery methods have been described, it can still be difficult or inefficient to introduce exogenous proteins into plants. A major barrier to progress is the cell wall which is primarily composed of polysaccharides and thus only permeable to small molecules. Here, we report a partial enzymatic cell wall digestion-mediated uptake method that efficiently delivers protein into the nucleus of plant cells. Such a method allowed efficient nuclear delivery of green fluorescent protein (GFP) flanked by two nuclear localization sequences (NLS) into Arabidopsis thaliana epidermal root cells without the usual need for large doses of nanoparticles or tissue cultures. We also show that switching from daylight to far-red light-grown conditions promotes effective protein penetration into deep cell layers. This study establishes that a partial enzymatic cell wall degradation could be applied to other cell organelles by changing the localization sequence, paving the way toward the rational engineering of plants. Full article

Pythiosis, a rare and formidable infectious disease caused by Pythium insidiosum, is characterized by profound uncertainties in achieving definitive diagnoses, suboptimal outcomes, and an exceptionally high mortality rate. Here, we present a rare case of human spinal pythiosis in southern China. With advanced metagenomic sequencing technology, Pythium insidiosum was pinpointed as the causative pathogen. We discovered that the inoculation of either tissue fragments or homogenate yielded more successful results and enabled a moderate extension of the culture duration to 5–10 days through an exhaustive comparison of diverse inoculation and culture conditions for general clinical specimens. A pronounced genetic affinity of the isolated strain towards the Pythium insidiosum strain MCC 13 was detected after a comprehensive whole-genome sequencing analysis. Antifungal agents exhibited negligible sensitivity towards Pythium insidiosum in an antimicrobial susceptibility test. Conversely, antibacterial agents such as oxazolidinones, tetracyclines, macrolides, and amphenicols demonstrated varying degrees of sensitivity, albeit with most of their minimum inhibitory concentrations (MICs) substantially surpassing the safe concentration ranges for effective clinical treatment. Notably, tigecycline stood out as a promising candidate, exhibiting favorable therapeutic effects at moderate concentrations, making it a potential drug of choice for the control of pythiosis. A combined susceptibility test suggested that combinations of tetracyclines with macrolides, oxazolidinones, and amphenicols exhibited synergistic antibacterial effects, with the combination of doxycycline and trimethoprim–sulfamethoxazole (TMP-SMX) in particular playing a pivotal role. To our surprise, the MICs of iron chelators, specifically deferiprone and deferoxamine, against the strain were exceedingly low, which led to the speculation that exogenous iron chelators may have competitively inhibited the iron-chelating enzymes of the strain. The research derived from this single, rare case has certain limitations, but considering that there are currently no reports of invasive infections of deep organs in humans caused by Pythium insidiosum, the above findings can offer novel insights into the treatment of invasive pythiosis. Combination therapy based on tetracyclines, especially tigecycline, the use of TMP-SMX, and the adjunctive use of iron chelators, represent promising approaches to tackle the clinical challenges in the treatment of invasive pythiosis. However, further studies, including similar cases of spinal pythiosis and in vivo trials, are still needed to validate them. In addition, while paying attention to the therapeutic potentials of the above plans, we should also closely monitor the risks and side effects that may arise from excessive MICs or the expanded use of related drugs during the treatment process. Full article

Medical device companies and regulatory bodies rely on a nondestructive bacterial sampling technique specified by the American Society for Testing and Materials (ASTM E1173-15) to test preoperative skin preparations (PSPs). Despite the widespread use of PSPs, opportunistic skin-flora pathogens remain the most significant contributor to surgical site infections, suggesting that the ASTM testing standard may be underreporting true dermal bioburden. We hypothesized that ASTM E1173-15 may fail to capture deep skin-dwelling flora. To test this hypothesis, we applied ASTM E1173-15 and a full-thickness skin sampling technique, which we established previously through application to the backs of seven pigs (Yorkshire/Landrace hybrid) following a clinically used PSP (4% chlorhexidine gluconate). The results showed that samples quantified using the full-thickness skin method consistently cultured more bacteria than the ASTM standard, which principally targeted surface-dwelling bacteria. Following PSP, the ASTM standard yielded 1.05 ± 0.24 log₁₀ CFU/cm², while the full-thickness tissue method resulted in 3.24 ± 0.24 log₁₀ CFU/cm², more than a 2 log₁₀ difference (p < 0.001). Immunofluorescence images corroborated the data, showing that Staphylococcus epidermidis was present in deep skin regions with or without PSP treatment. Outcomes suggested that a full-thickness sampling technique may better evaluate PSP technologies as it resolves bioburdens dwelling in deeper skin regions. Full article

Wound healing is important for skin after deep injuries or burns, which can lead to hospitalization, long-term morbidity, and mortality. In this field, tissue-engineered skin substitutes have therapy potential to assist in the treatment of acute and chronic skin wounds, where many requirements are still unmet. Hence, in this study, a novel type of biocompatible ternary polymer hybrid hydrogel scaffold was designed and produced through an entirely eco-friendly aqueous process composed of carboxymethyl cellulose, chitosan, and polyvinyl alcohol and chemically cross-linked by citric acid, forming three-dimensional (3D) matrices, which were biofunctionalized with L-arginine (L-Arg) to enhance cellular adhesion. They were applied as bilayer skin biomimetic substitutes based on human-derived cell cultures of fibroblasts and keratinocytes were seeded and grown into their 3D porous structures, producing cell-based bio-responsive hybrid hydrogel scaffolds to assist the wound healing process. The results demonstrated that hydrophilic hybrid cross-linked networks were formed via esterification reactions with the 3D porous microarchitecture promoted by foam templating and freeze-drying. These hybrids presented chemical stability, physicochemical properties, high moisture adsorption capacity, surface properties, and a highly interconnected 3D porous structure well suited for use as a skin substitute in wound healing. Additionally, the surface biofunctionalization of these 3D hydrogel scaffolds with L-arginine through amide bonds had significantly enhanced cellular attachment and proliferation of fibroblast and keratinocyte cultures. Hence, the in vivo results using Hairless mouse models (an immunocompromised strain) confirmed that these responsive bio-hybrid hydrogel scaffolds possess hemocompatibility, bioadhesion, biocompatibility, adhesiveness, biodegradability, and non-inflammatory behavior and are capable of assisting the skin wound healing process. Full article

To investigate the effects of predation by the paddle crab Charybdis japonica on the culture and survival of scallops (Mizuhopecten yessoensis) during bottom culture, we investigated the behavioral characteristics of three sizes (small, medium, and large) of scallops in response to exposure to crabs. We found that scallops escaped from crab predation by continuous shell closure or movement. Shell closure force increased with scallop size, and scallops of the same size that were stimulated by the presence of crabs closed their shell more frequently than control scallops. We also measured the activities of superoxide dismutase, catalase, arginine kinase, and octopine dehydrogenase in the gill, adductor muscle, and mantle of scallops before and after exposure to predation. Tissues that showed significant differences between control and test specimens were selected for deep sequencing of the transcriptome to identify and validate the key genes that were sensitive to predation. We found that when M. yessoensis is stimulated by the presence of predators, its behavioral characteristics and related physiological and ecological indexes undergo significant changes. The results are relevant for developing specifications for M. yessoensis seedling casting during bottom culture. Full article

Percutaneous implants osseointegrated into the residuum of a person with limb amputation need to provide mechanical stability and protection against infections. Although significant progress has been made in the biointegration of percutaneous implants, the problem of forming a reliable natural barrier at the level of the surface of the implant and the skin and bone tissues remains unresolved. The use of a microporous implant structure incorporated into the Skin and Bone Integrated Pylon (SBIP) should address the issue by allowing soft and bone tissues to grow directly into the implant structure itself, which, in turn, should form a reliable barrier to infections and support strong osseointegration. To evaluate biological interactions between dermal fibroblasts and MC3T3-E1 osteoblasts in vitro, small titanium discs (with varying pore sizes and volume fractions to achieve deep porosity) were fabricated via 3D printing and sintering. The cell viability MTT assay demonstrated low cytotoxicity for cells co-cultured in the pores of the 3D-printed and sintered Ti samples during the 14-day follow-up period. A subsequent Quantitative Real-Time Polymerase Chain Reaction (RT-PCR) analysis of the relative gene expression of biomarkers that are associated with cell adhesion (α2, α5, αV, and β1 integrins) and extracellular matrix components (fibronectin, vitronectin, type I collagen) demonstrated that micropore sizes ranging from 200 to 500 µm of the 3D printed and sintered Ti discs were favorable for dermal fibroblast adhesion. For example, for representative 3D-printed Ti sample S6 at 72 h the values were 4.71 ± 0.08 (α2 integrin), 4.96 ± 0.08 (α5 integrin), 4.71 ± 0.08 (αV integrin), and 1.87 ± 0.12 (β1 integrin). In contrast, Ti discs with pore sizes ranging from 400 to 800 µm demonstrated the best results (in terms of marker expression related to osteogenic differentiation, including osteopontin, osteonectin, osteocalcin, TGF-β1, and SMAD4) for MC3T3-E1 cells. For example, for the representative 3D sample S4 on day 14, the marker levels were 11.19 ± 0.77 (osteopontin), 7.15 ± 0.29 (osteonectin), and 6.08 ± 0.12 (osteocalcin), while for sintered samples the levels of markers constituted 5.85 ± 0.4 (osteopontin), 4.45 ± 0.36 (osteonectin), and 4.46 ± 0.3 (osteocalcin). In conclusion, the data obtained show the high biointegrative properties of porous titanium structures, while the ability to implement several pore options in one structure using 3D printing makes it possible to create personalized implants for the best one-time integration with both skin and bone tissues. Full article

Background: Metastatic tumors of the oro-facial tissuesare rare, with an incidence ranging between 1% and 8% of all oral malignant tumors. Generally reported with a peak of incidence in the 5–7th decades but possibly occurring at any age, metastases may represent the first sign of an occult cancer or manifest in patients with an already known history of a primary carcinoma, mostly from the lungs, kidney, prostate, and colon/rectum in males, and the uterus, breast, lung, and ovary in females. In the oro-facial tissues, the most involved sites are the oral mucosa, gingiva/jawbones, tongue, and salivary glands. Methods: A broad and deep literature review with a comprehensive analysis of the existing research on oro-facial metastases from renal-cell carcinoma (RCC) was conducted by searching the most used databases, with attention also paid to the clear-cell histological variant, which is the most frequent one. Results: Among the 156 analyzed studies, 206 cases of oro-facial metastases of renal cancer were found in patients with an average age of 60.9 years (145 males, 70.3%; 61 females, 29.6%). In almost 40% of the cases, metastasis represented the first clinical manifestation of the primary tumor, and 122 were histologically diagnosed as clear-cell renal-cell carcinoma (ccRCC) (59.2%). The tongue was involved in most of the cases (55 cases, 26.7%), followed by the gingiva (39 cases, 18.9%), mandible (35 cases, 16.9%), maxilla (23 cases, 11.1%), parotid gland (22 cases, 10.6%), buccal mucosa (11 cases, 5.3%), lips (7 cases, 3.3%), hard palate (6 cases, 2.8%), soft palate, masticatory space, and submandibular gland (2 cases, 0.9%), and lymph nodes, tonsils, and floor of the mouth (1 case, 0.4%). Among the 122 ccRCCs (84 males, 68.8%; 38 females, 31.1%), with an average age of 60.8 years and representing in 33.6% the first clinical manifestation, the tongue remained the most frequent site (31 cases, 25.4%), followed by the gingiva (21 cases, 17.2%), parotid gland (16 cases, 13.1%), mandibular bone (15 cases, 12.2%), maxillary bone (14 cases, 11.4%), buccal mucosa and lips (6 cases, 4.9%), hard palate (5 cases, 4%), submandibular gland and soft palate (2 cases, 1.6%), and lymph nodes, tonsils, oral floor, and masticatory space (1 case, 0.8%). The clinical presentation in soft tissues was mainly represented by a fast-growing exophytic mass, sometimes accompanied by pain, while in bone, it generally presented as radiolucent lesions with ill-defined borders and cortical erosion. Conclusions: The current comprehensive review collected data from the literature about the incidence, site of occurrence, age, sex, and survival of patients affected by oro-facial metastases from renal-cell carcinoma, with particular attention paid to the cases diagnosed as metastases from clear-cell renal-cell carcinoma, which is the most frequent histological variant. Clinical differential diagnosis is widely discussed to provide clinicians with all the useful information for an early diagnosis despite the effective difficulties in recognizing such rare and easily misdiagnosed lesionsTheir early identification represents a diagnostic challenge, especially when the clinical work-up is limited to the cervico–facial region. Nevertheless, early diagnosis and recently introduced adjuvant therapies may represent the key to better outcomes in such patients. Therefore, general guidelines about the clinical and radiological identification of oro-facial potentially malignant lesions should be part of the cultural background of any dentist. Full article

There is great interest in developing effective therapies for the treatment of skin wounds accompanied by deep tissue losses and severe infections. We have attempted to prepare biohybrids formed of agglomerates of mesenchymal stem cells (MSCs) with gelatin hydrogel beads (GEL beads) delivering bacteriophages (phages) as antibacterial agents and/or basic fibroblast growth factor (bFGF) for faster and better healing, providing combined therapies for these types of skin wounds. The gelatin beads were produced through a two-step process using basic and/or acidic gelatins with different isoelectric points. Escherichia coli (E. coli) and its specific T4 phages were propagated. Phages and/or bFGF were loaded within the GELs and their release rates and modes were obtained. The phage release from the basic GEL beads was quite fast; in contrast, the bFGF release from the acidic GEL beads was sustained, as anticipated. MSCs were isolated from mouse adipose tissues and 2D-cultured. Agglomerates of these MSCs with GEL beads were formed and maturated in 3D cultures, and their time-dependent changes were followed. In these 3D culture experiments, it was observed that the agglomerates with GEL beads were very healthy and the MSCs formed tissue-like structures in 7 days, while the MSC agglomerates were not healthy and shrunk considerably as a result of cell death. Full article

Clostridial myonecrosis, commonly known as gas gangrene (GG), is a rapidly progressing and potentially fatal bacterial infection that primarily affects muscle and soft tissue. In the United States, the incidence of GG is roughly 1000 cases per year, while, in developing countries, the incidence is higher. This condition is most often caused by Clostridium perfringens, a Gram-positive, spore-forming anaerobic bacterium widely distributed in the environment, although other Clostridium species have also been reported to cause GG. The CP genome contains over 200 transport-related genes, including ABC transporters, which facilitate the uptake of sugars, amino acids, nucleotides, and ions from the host environment. There are two main subtypes of GG: traumatic GG, resulting from injuries that introduce Clostridium spores into deep tissue, where anaerobic conditions allow for bacterial growth and toxin production, and spontaneous GG, which is rarer and often occurs in immunocompromised patients. Clostridium species produce various toxins (e.g., alpha, theta, beta) that induce specific downstream signaling changes in cellular pathways, causing apoptosis or severe, fatal immunological conditions. For example, the Clostridium perfringens alpha toxin (CPA) targets the host cell’s plasma membrane, hydrolyzing sphingomyelin and phosphatidylcholine, which triggers necrosis and apoptosis. The clinical manifestations of clostridial myonecrosis vary. Some patients experience the sudden onset of severe pain, swelling, and muscle tenderness, with the infection progressing rapidly to widespread tissue necrosis, systemic toxicity, and, if untreated, death. Other patients present with discharge, pain, and features of cellulitis. The diagnosis of GG primarily involves clinical evaluation, imaging studies such as X-rays, computer tomography (CT) scans, and culture. The treatment of GG involves surgical exploration, broad-spectrum antibiotics, antitoxin, and hyperbaric oxygen therapy, which is considered an adjunctive treatment to inhibit anaerobic bacterial growth and enhance the antibiotic efficacy. Early recognition and prompt, comprehensive treatment are critical to improving the outcomes for patients affected by this severe and life-threatening condition. Full article

Necrotizing fasciitis (NF) is a life-threatening soft-tissue infection affecting the deep fascia and subcutaneous tissue. It is characterized by a fulminant course and high mortality rates. NF of the head and neck is very rare, with most cases being odontogenic in origin. The purpose of this study is to comprehensively review the most important features of cervical necrotizing fasciitis (CNF) in adults and add our experience in the management of this entity. The most common isolated organisms are Streptococcus spp. and Staphylococcus spp. If the infection progresses to descending mediastinitis, the prognosis becomes very poor. Since the initial clinical features can be similar to those of a non-necrotizing deep cervical infection, a high degree of suspicion is critical for an early diagnosis. A computed tomography scan is essential for the diagnosis and to define the extent of the infection/rule out descending mediastinitis. Early and aggressive surgical debridement of all compromised tissue and antibiotic therapy and fluid resuscitation are essential and should not wait for bacterial culture results. Despite prompt and adequate treatment, the mortality of CNF can be as high as 35%. Full article