Search Results (48)

Platelet-rich plasma (PRP) has become an increasingly valuable biologic approach for personalized regenerative medicine because of its potent anti-inflammatory/healing effects. It is thought to be an excellent source of growth factors that can promote tissue healing and lessen fibrosis. Although this treatment has demonstrated effectiveness in numerous disease areas, its impact on pulmonary fibrosis (PF) caused by silver nanoparticles (AgNPs) via its antiapoptotic effects remains to be explored. AgNPs were synthesized biologically by Bacillus megaterium ATCC 55000. AgNP characterization was carried out via UV–Vis spectroscopy, X-ray diffraction (XRD), dynamic light scattering (DLS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) imaging to reveal monodispersed spheres with a mean diameter of 45.17 nm. A total of 48 male Wistar rats divided into six groups, with 8 rats per group, were used in the current study on the basis of sample size and power. The groups used were the PRP donor, control, AgNP, AgNP + PRP, AgNP + dexamethasone (Dexa) rat groups, and a recovery group. Body weights, hydroxyproline (HP) levels, and CASP3 and TWIST1 gene expression levels were assessed. H&E and Sirius Red staining were performed. Immunohistochemical studies for inducible nitric oxide synthase (iNOS) and cluster of differentiation 68 (CD68) with histomorphometry were conducted. A significant reduction in body weight (BWt) was noted in the AgNP group compared with the AgNP + PRP group (p < 0.001). HP, CASP3, and TWIST1 expression levels were significantly increased by AgNPs but decreased upon PRP (p < 0.001) treatment. Compared with those in the control group, the adverse effects of AgNPs included PF, lung alveolar collapse, thickening of the interalveolar septa, widespread lymphocytic infiltration, increased alveolar macrophage CD68 expression, and iNOS positivity in the cells lining the alveoli. This work revealed that PRP treatment markedly improved the histopathological and immunohistochemical findings observed in the AgNP group in a manner comparable to that of the Dexa. In conclusion, these results demonstrated the therapeutic potential of PRP in a PF rat model induced via AgNPs. This study revealed that PRP treatment significantly improved the histopathological and immunohistochemical alterations observed in the AgNP-induced group, with effects comparable to those of the Dexa. In conclusion, these findings highlight the therapeutic potential of PRP in a rat model of AgNP-induced PF. Full article

Background/Objectives: Background: COVID-19 pneumonia leads to alveolar collapse and parenchymal infiltration, contributing to lung volume loss and respiratory failure. Objectives: To quantify lung volume loss and recovery in moderate and severe cases, explore mechanisms of respiratory failure, and correlate imaging findings with histopathological changes. Methods: We retrospectively analyzed 43 patients with moderate/severe COVID-19. CT scans from the acute phase and at 3–12 months follow-ups were processed using 3D Slicer. Infiltrated (−650 to −200 HU) and collapsed (−200 to 0 HU) lung regions were quantified and summed to define the affected lung volume. CT severity scores and total affected percentage were compared with lung volume loss. Histopathological analysis of three autopsy cases was used to support imaging findings. Results: Median acute phase lung volume loss was 30.6%. Patients with <25%, 25–50%, and >50% affected lung had median losses of 6.5%, 35.7%, and 39.8%, respectively. Volume loss strongly correlated with affected lung percentage (r = 0.72, p < 0.000001) and moderately with CT severity score (r = 0.52, p < 0.01). Histology confirmed alveolar area reductions over 65% in infiltrated regions. Conclusions: Lung volume loss reflects both imaging severity and histopathological damage, offering insights into the mechanisms of COVID-19 respiratory failure. CT volumetry is a valuable tool for assessing parenchymal injury and monitoring recovery, and 3D Slicer provides an accessible platform for implementing this approach. Full article

Background: Alveolar ridge preservation (ARP) is widely used in clinical practice to prevent horizontal and vertical bone loss following tooth extraction. Conventional ARP uses a single coverage material with bone graft materials on a simple tooth extraction site. The objective of this study was to evaluate the clinical efficacy of a new double-layer ARP technique that additionally covers a collagen matrix at the top position, especially on the periodontally collapsed region following tooth extraction. Methods: In a clinical study process comparing our newly attempted ARP with the widely used conventional ARP, we discovered the clinical efficacy of our new ARP for specially selected cases. Because the extraction socket wall had collapsed and the entire ridge needed to be reconstructed, this procedure should be described as alveolar ridge augmentation. Results: Additional coverage of the collagen matrix protected the internal bone grafting and promoted external soft tissue regeneration and healing in sample cases. Conclusions: In conclusion, our procedure promotes the new generation of hard and soft tissues. It is particularly effective in regions requiring flapped surgery, such as areas with periodontal disease, long-span areas requiring multiple tooth extractions, and areas in which there is wide destruction of hard and soft tissues. Through this proof-of-concept case study, we aimed to standardize and evaluate this unprecedented surgical technique. Full article

Background/Objectives: The socket-shield technique (SST) was developed to preserve the facial/buccal portion of a tooth root to prevent post-extraction ridge resorption. It has gained attention for use in anterior implant sites, but its application in posterior sites remains unexplored. The aim of this case report was to report a proof-of-principle case using SST in a lower molar site and evaluate its effectiveness in preserving tissues. Methods: A 34-year-old non-smoking patient with a non-restorable mandibular first molar (tooth #36) underwent immediate implant placement with the SST. The tooth’s crown was removed, and the buccal segments of the roots were retained as “shields” while the implant was placed in the center of the socket. Preoperative and postoperative cone-beam CT (CBCT) scans and clinical exams were used to assess outcomes up to 12 months. Results: The SST procedure was completed uneventfully. CBCT after 4 months and 12 months showed minimal horizontal bone loss: ~0.2 mm at 4 months; ~0.1 mm additional loss by 12 months. The peri-implant soft tissue profile remained stable, and the implant achieved osseointegration with high primary and secondary stability. Conclusions: In this clinical case, the socket-shield technique effectively preserved alveolar bone and soft tissue contours in a molar extraction site, avoiding the ridge collapse often seen post-extraction. This suggests SST may be a viable tissue preservation approach in posterior sites; however, long-term follow-up and further studies are needed to confirm sustained outcomes and validate the technique’s predictability. Full article

Sepsis is a leading cause of death in hospitalized patients. The underlying pathophysiologic mechanisms of sepsis have not been fully elucidated thus far. The receptor of programmed cell death 1 (PD-1) and its ligand (PD-L1), in combination with the Toll-like receptors (TLRs), seem to contribute considerably in systematic responses during sepsis. Investigating the relationship between them and identifying potential target pathways is important in the future management of sepsis, especially in relation to acute lung injury. This study investigated the interactions between TLR-5, -6, and -9 and PD-1/PD-L1 expression in a septic mouse model. Sixty C57BL/6J mice were included and categorized in six study groups. Three sepsis (S) groups (24 h, 48 h, and 72 h) and three sham (Sh) groups (24 h, 48 h, and 72 h) were created. Cecal ligation and puncture (CLP) was utilized to simulate sepsis in the S groups. Hematological analysis and lung tissue histopathological analysis were performed after 24 h, 48 h, and 72 h. Significant decreases in S groups compared to Sh groups in WBC and lymphocyte counts at 24, 48, and 72 h were observed. Significant increases in S groups compared to Sh groups in RBC and monocyte counts, IL-6 and IL-10 levels, alveolar flooding, and alveolar collapse were demonstrated by histopathological analysis. This study suggested a strong correlation between TLR expression and PD-1/PD-L1 up-regulation in lung tissue during sepsis. These molecules, also, seem to contribute to the histopathological changes in lung tissue during sepsis, leading to acute lung injury. Full article

The alveolar ridge undergoes a loss in volume and atrophy after tooth extraction. Understanding the wound healing and bone regeneration process after tooth extraction is a key factor in the insertion of dental implants. Therefore, the aim of the present study was to analyze the socket healing process after the extraction of upper premolars based on cone beam computed tomography (CBCT) over six months. Special focus was placed on the morphological changes in the alveolar crest and within the socket. A retrospective analysis of patients in need of tooth extraction in the upper premolar region was performed in this study. All patients received flapless tooth extraction under local anesthesia and CBCT immediately after tooth extraction. Further CBCT analysis was performed after three months for the first group (n = 18) and after six months for the second group (n = 18). The results showed that all sockets underwent an inward movement of the defect walls towards the defect center, resulting in reduced total alveolar ridge volume and defect volume. This result was observed after three months and persisted after six months. The inward movement was quantified as a vertical socket collapse of up to 30.1 ± 9.0% after three months and 34.3 ± 6.7% after six months. The horizontal inward movement was quantified as a buccal socket collapse of 47.7 ± 12.3% after three months and 55.7 ± 29.1% after six months. New bone formation within the socket was evident, especially in the occlusal part of the socket. Additionally, bone formation was primarily observed as bone apposition along the socket walls and did not reach the defect center in most cases. The combination of socket collapse and bone apposition led to the formation of cavitations inside the socket that were mostly localized under the occlusal part. These novel findings with respect to socket collapse and formation of cavitation represent a paradigm shift and call for reconsidering the current understanding of socket healing. Based on the data, socket healing should be understood as a patient-specific process that requires 3D radiographic analysis for planning dental implants. Full article

Surfactant proteins A and D (SP-A and SP-D) belong to the collectin subfamily of C-type oligomeric lectins. They are pattern-recognition molecules (PRMs), able to recognise pathogen- or danger-associated molecular patterns (PAMPs, DAMPs) in the presence of Ca²⁺ cations. That property enables opsonisation or agglutination of non-self or altered/abnormal self cells and contributes to their clearance. Like other collectins, SP-A and SP-D are characterised by the presence of four distinct domains: a cysteine-rich domain (at the N-terminus), a collagen-like region, an α-helical neck domain and a globular carbohydrate-recognition domain (CRD) (at the C-terminus). Pulmonary surfactant is a lipoprotein complex, preventing alveolar collapse by reducing surface tension at the air–liquid interface. SP-A and SP-D, produced by type II alveolar epithelial cells and Clara cells, are not only pattern-recognition molecules but also contribute to the surfactant structure and homeostasis. Moreover, they are expressed in a variety of extrapulmonary sites where they are involved in local immunity. The term “cancer” includes a variety of diseases: tumours start from uncontrolled growth of abnormal cells in any tissue which may further spread to other sites of the body. Many cancers are incurable, difficult to diagnose and often fatal. This short review summarises anti- and pro-tumorigenic associations of SP-A and SP-D as well as perspectives of their usefulness in cancer diagnosis and therapy. Full article

Background: A complement imbalance in lung alveolar tissue can play a deteriorating role in COVID-19, leading to acute respiratory distress syndrome (ARDS). CD55 is a transmembrane glycoprotein that inhibits the activation of the complement system at the intermediate cascade level, blocking the activity of the C3 convertase. Objective: In our study, lung specimens from COVID-19 and ARDS-positive COVID+/ARDS+ patients were compared with COVID-19 and ARDS-negative COVID–/ARDS– as well as COVID–/ARDS+ patients. Methods: Histochemical staining and immunolabeling of CD55 protein were performed. Results: The COVID–/ARDS– specimen showed higher expression and homogeneous distribution of glycosaminoglycans as well as compactly arranged elastic and collagen fibers of the alveolar walls in comparison to ARDS-affected lungs. In addition, COVID–/ARDS– lung tissues revealed stronger and homogenously distributed CD55 expression on the alveolar walls in comparison to the disrupted COVID–/ARDS+ lung tissues. Conclusions: Even though the collapse of the alveolar linings and the accumulation of cellular components in the alveolar spaces were characteristic of COVID+/ARDS+ lung tissues, evaluating CD55 expression could be relevant to understand its relation to the disease. Furthermore, targeting CD55 upregulation as a potential therapy could be an option for post-infectious complications of COVID-19 and other inflammatory lung diseases in the future. Full article

Administration of oxygen microbubbles (OMBs) has been shown to increase oxygen and decrease carbon dioxide in systemic circulation, as well as reduce lung inflammation and promote survival in preclinical models of hypoxia caused by lung injury. However, their impact on microenvironmental oxygenation remains unexplored. Herein, we investigated the effects of intraperitoneal administration of OMBs in anesthetized rats exposed to hypoxic ventilation (FiO₂ = 0.14). Blood oxygenation and hemodynamics were evaluated over a 2 h time frame, and then organ and tissue samples were collected for hypoxic and metabolic analyses. Data showed that OMBs improved blood SaO₂ (~14%) and alleviated tissue hypoxia within the microenvironment of the kidney and intestine at 2 h of hypoxia. Metabolomic analysis revealed OMBs induced metabolic differences in the cecum, liver, kidney, heart, red blood cells and plasma. Within the spleen and lung, principal component analysis showed a metabolic phenotype more comparable to the normoxic group than the hypoxic group. In the spleen, this shift was characterized by reduced levels of fatty acids and 2-hydroxygluterate, alongside increased expression of antioxidant enzymes such as glutathione and hypoxanthine. Interestingly, there was also a shuttle effect within the metabolism of the spleen from the tricarboxylic acid cycle to the glycolysis and pentose phosphate pathways. In the lung, metabolomic analysis revealed upregulation of phosphatidylethanolamine and phosphatidylcholine synthesis, indicating a potential indirect mechanism through which OMB administration may improve lung surfactant secretion and prevent alveolar collapse. In addition, cell-protective purine salvage was increased within the lung. In summary, oxygenation with intraperitoneal OMBs improves systemic blood and local tissue oxygenation, thereby shifting metabolomic profiles of the lung and spleen toward a healthier normoxic state. Full article

The inhalation of gasoline vapors (GV) is associated with developing various pathologies. Particularly, oil refinery and gas station workers are at a greater risk of developing lung cancer, kidney cancer, bladder cancer, and hematological disorders, including acute myeloid leukemia. Therefore, preventing the harmful effects of GV and alleviating their consequences appear to be important and timely issues. In this study, we investigated the potential of vitamin D₃, turmeric powder, and their combination to ameliorate the toxicity of gasoline fumes in rats. Separate groups of animals fed with a standard rodent diet, with or without the supplementation of vitamin D₃ (750 IU/kg body weight) and/or turmeric powder (0.5%, w/w, in food), were untreated or treated with GV (11.5 ± 1.3 cm³/h/m³/day) for 30, 60, or 90 days. Changes in the body weight were monitored weekly. Histological, biochemical, and hematological parameters were determined at the end of each treatment period. While the exposure of rats to GV resulted in a time-dependent reduction in body weight, supplementation with vitamin D₃, but not with turmeric root powder or their combination, partially prevented weight loss. Macroscopical and histological analyses showed pronounced time-dependent changes in the organs and tissues of GV-treated rats. These included alveolar wall collapse in the lungs, the destruction of the lobular structure and hepatocytolysis in the liver, the shrinkage and fragmentation of glomeruli in the kidneys, and the disorganization of the lymphoid follicles in the spleen. However, co-treatment with the nutritional supplements tested, especially vitamin D₃, noticeably alleviated the above conditions. This was accompanied by a significant improvement in the blood chemistry and hematological parameters. Collectively, our results demonstrate that the harmful effects of environmental exposure to GV can be reduced upon supplementation of vitamin D₃. The fact that the protective activity of vitamin D₃ alone was higher than that of turmeric root powder or the combined treatment suggests that combinations of these supplements may not always be more beneficial than each agent applied separately. Full article

Lung aging triggers the onset of various chronic lung diseases, with alveolar repair being a key focus for alleviating pulmonary conditions. The regeneration of epithelial structures, particularly the differentiation from type II alveolar epithelial (AT2) cells to type I alveolar epithelial (AT1) cells, serves as a prominent indicator of alveolar repair. Nonetheless, the precise role of aging in impeding alveolar regeneration and its underlying mechanism remain to be fully elucidated. Our study employed histological methods to examine lung aging effects on structural integrity and pathology. Lung aging led to alveolar collapse, disrupted epithelial structures, and inflammation. Additionally, a relative quantification analysis revealed age-related decline in AT1 and AT2 cells, along with reduced proliferation and differentiation capacities of AT2 cells. To elucidate the mechanisms underlying AT2 cell functional decline, we employed transcriptomic techniques and revealed a correlation between inflammatory factors and genes regulating proliferation and differentiation. Furthermore, a D-galactose-induced senescence model in A549 cells corroborated our omics experiments and confirmed inflammation-induced cell cycle arrest and a >30% reduction in proliferation/differentiation. Physiological aging-induced chronic inflammation impairs AT2 cell functions, hindering tissue repair and promoting lung disease progression. This study offers novel insights into chronic inflammation’s impact on stem cell-mediated alveolar regeneration. Full article

Introduction: Although various surgical techniques have been utilized in the reconstruction of severely resorbed alveolar bone, its regeneration is still regarded as a major challenge. Most of the surgical techniques used in advanced ridge augmentation have the disadvantages of prolonging the patient’s edentulous healing and increasing the need for surgical revisits because simultaneous implant placement is not allowed. This report presents a new and simplified method for advanced ridge augmentation, which utilizes a vertical tenting device. Case Presentation: The first case presented the reconstruction of the mandibular posterior region with severely resorbed alveolar bone due to peri-implantitis using tenting pole abutment for ridge augmentation. The second and third cases presented three-dimensional ridge augmentations in severely resorbed ridges due to periodontitis. The last case presented horizontal ridge augmentation using a vertical tenting device. All cases were performed under local anesthesia. Implants were simultaneously placed in the bone defect area. A vertical tensioning device was then connected to the implant platform to minimize the collapse of the bone graft during the bone regeneration period due to the contraction of the soft tissue matrix. A sticky bone graft was transplanted onto the exposed surface of the implant and on top of the vertical tensioning device. After covering with an absorbable barrier membrane, the soft tissues were sutured without tension. Conclusions: In all cases, prosthetic restorations were provided to patients after a bone grafting period of 5–6 months, leading to a rapid restoration of masticatory function. Results tracked for up to 6 years revealed observed stable reconstruction of the alveolar bone. The use of a vertical tenting device can prevent the collapse of biomaterials in the augmented ridge during the healing period, leading to predictable outcomes when achieving three-dimensional ridge augmentation. Full article

Pulmonary fibrosis, severe alveolitis, and the inability to restore alveolar epithelial architecture are primary causes of respiratory failure in fatal COVID-19 cases. However, the factors contributing to abnormal fibrosis in critically ill COVID-19 patients remain unclear. This study analyzed the histopathology of lung specimens from eight COVID-19 and six non-COVID-19 postmortems. We assessed the distribution and changes in extracellular matrix (ECM) proteins, including elastin and collagen, in lung alveoli through morphometric analyses. Our findings reveal the significant degradation of elastin fibers along the thin alveolar walls of the lung parenchyma, a process that precedes the onset of interstitial collagen deposition and widespread intra-alveolar fibrosis. Lungs with collapsed alveoli and organized fibrotic regions showed extensive fragmentation of elastin fibers, accompanied by alveolar epithelial cell death. Immunoblotting of lung autopsy tissue extracts confirmed elastin degradation. Importantly, we found that the loss of elastin was strongly correlated with the induction of neutrophil elastase (NE), a potent protease that degrades ECM. This study affirms the critical role of neutrophils and neutrophil enzymes in the pathogenesis of COVID-19. Consistently, we observed increased staining for peptidyl arginine deiminase, a marker for neutrophil extracellular trap release, and myeloperoxidase, an enzyme-generating reactive oxygen radical, indicating active neutrophil involvement in lung pathology. These findings place neutrophils and elastin degradation at the center of impaired alveolar function and argue that elastolysis and alveolitis trigger abnormal ECM repair and fibrosis in fatal COVID-19 cases. Importantly, this study has implications for severe COVID-19 complications, including long COVID and other chronic inflammatory and fibrotic disorders. Full article

Artificial intelligence (AI) can make intelligent decisions in a manner akin to that of the human mind. AI has the potential to improve clinical workflow, diagnosis, and prognosis, especially in radiology. Acute respiratory distress syndrome (ARDS) is a very diverse illness that is characterized by interstitial opacities, mostly in the dependent areas, decreased lung aeration with alveolar collapse, and inflammatory lung edema resulting in elevated lung weight. As a result, lung imaging is a crucial tool for evaluating the mechanical and morphological traits of ARDS patients. Compared to traditional chest radiography, sensitivity and specificity of lung computed tomography (CT) and ultrasound are higher. The state of the art in the application of AI is summarized in this narrative review which focuses on CT and ultrasound techniques in patients with ARDS. A total of eighteen items were retrieved. The primary goals of using AI for lung imaging were to evaluate the risk of developing ARDS, the measurement of alveolar recruitment, potential alternative diagnoses, and outcome. While the physician must still be present to guarantee a high standard of examination, AI could help the clinical team provide the best care possible. Full article

The objective of this study was to investigate the preventive effects of polysaccharides extracted from the roots of Arctium lappa (ALP) against acute lung injury (ALI) models induced by lipopolysaccharide (LPS). The polysaccharides were extracted and characterized, and their anti-inflammatory and antioxidant capacities were assessed. The findings demonstrated that ALP could mitigate the infiltration of inflammatory cells and reduce alveolar collapse in LPS-induced ALI in mice. The expression levels of the pro-inflammatory factor TNF-α decreased, while the anti-inflammatory factor IL-10 increased. Furthermore, the administration of ALP improved the activities of lung antioxidant enzymes, including SOD, GSH, and CAT, and lowered MDA levels. These results suggest that ALP exhibits a preventive effect on ALI and has potential as an alternative treatment for lung injury. Full article