A model for calculating beta exposure doses to tracheobronchial cells during movement of a point source

The article describes a model and method for calculating beta-exposure doses to secretory and basal cells of the tracheobronchial part of the respiratory tract when a point source of 1 Bq activity moves along the inner surface of respiratory formations. The calculations, that used for proposed model, were performed by using a 90Y point source as an example. The dose calculation model takes into account the speed o f movement of the radiation source in each respiratory formation, the size of the respiratory formations, and the depth of the secretory and basal cells. The dose calculation is based on the dose rate attenuation functions published by W. G. Cross et al. (DOI: 10.1097/00004032-199208000-00002). The calculations were performed for a cylindrical model of a respiratory formation. Two kinds of cells were considered for the dose estimation: cells irradiated without beta-particle exit into bronchial lumen (type 1 cells) and cells irradiated due to beta-par­ticle exit into bronchial lumen (type 2 cells). The results of calculations showed, that as far as the generation number increasing, the average irradiation doses of the type 1 cells are 10 or more times greater than those of the type 2 cells. With increasing generation number in the tracheobronchial tree, doses per cells increase by several orders of magnitude. The highest doses are formed in bronchioles of generations 9-15, reaching units and tens of mGy. In spite of the fact that the number of generation increases, the total number of irradiated cells decreases, the collective doses of irradiated cells (sum of doses to all cells of the respiratory formation) in the last generations are 30-50 times higher than the doses of the first generations. Thus, in case of a single point source, there is a significant (by many orders of magnitude) scatter of doses to individual cells in indi­vidual respiratory formation, as well as significant differences in average doses of trachea, individual bronchi and bronchioles.

Endobronchial Metastasis of Renal Carcinoma: A Case Report and Review of Previous Literature

The definition of endobronchial metastasis (EBM) lacks clarity because it is currently based on the judgments of surgeons; it is rare in patients with nonpulmonary malignancies. Although EBM represents an advanced stage of malignancy, it does not necessarily indicate a poorer prognosis than that for its primary tumors. The present study defines EBM as bronchoscopy-visible lesions with histologically confirmed primary extrapulmonary tumors, excluding those primary lung tumors with involvement of the bronchial lumen. A bronchoscopy and biopsy provide strong proof for diagnosis. Complete surgical resection is the best choice for patients with EBM. This study analyzed the case of a 69-year-old male patient who had undergone a radical left nephrectomy several years previously after the identification of a bronchoscopy-visible lesion in the left main bronchus. The lesion was initially diagnosed as an angiogenic tumor but was eventually confirmed by surgical biopsy as EBM from the left kidney. After diagnosis, the patient underwent a left pneumonectomy. The analysis of this case focused on diagnosis, symptoms, radiographic findings, treatment, and prognosis. A review of the previous literature relating to EBM was also conducted.

Lung Histopathology in Baclofen Intoxication

The aim of the study: to assess the lung histopathology in acute intoxication with baclofen alone and its combination with alcohol (in the same dose) 3 hours after the ingestion.Materials and methods. The study was performed on 15 male Wistar rats weighing 290-350 g and aged 20 weeks. The animals were divided into 3 groups, 5 animals each: control group that included intact rats; Group 1 composed of rats received baclofen alone; Group 2 that included rats received a combination of baclofen and ethanol. Baclofen was administered orally at a dose of 85 mg/kg animal weight under anesthesia (chloralose), and 40% ethanol, 7 ml/kg animal weight, was orally administered along with baclofen at the same dose. Animals of all groups were sacrificed after 3 hours by overdosing anesthetic agent. Lung tissue samples were examined by light microscopy using a video system at x400 magnification. The following histological characteristics were evaluated: circulatory disorders (engorged capillaries and venules, hemorrhages in interalveolar septa and alveoli, sludge), atelectasis (including partial), emphysema, cellular response (increased WBCs in the interalveolar septal area), thickening of interalveolar septa due to edema, epithelial desquamation into bronchial lumen. The diameter of alveoli and thickness of interalveolar septa were measured.Results. Three hours after the baclofen administration, circulatory disorders in the lungs (engorged venules and capillaries, hemorrhages in the interalveolar septa, sludge), emphysema, atelectasis (complete and partial) as well as cellular response (leucocyte infiltration of interalveolar septa) were detected. In the Group 2, baclofen resulted in circulatory disorders (engorged venules and capillaries, sludge), emphysema, atelectasis (complete and incomplete), cellular response (infiltration with leukocytes), as well as fluid in the lumen of bronchioles. In Group 1, the alveolar diameter was significantly larger than in the control group and Group 2, while the thickness of the interalveolar septa was lower. In group 2, alveolar diameter was significantly less than in group 1, but still greater than in the control group. The thickness of the interalveolar septa in group 2 was significantly greater than in the control group and group 1.Conclusion. After administration of baclofen alone and in combination with ethanol, the following alterations were found in the lungs: circulation disorders (venular and capillary engorgement, sludge), increased vascular permeability because of developing hypoxia, leukocyte infiltration of interalveolar septa. The monitoring of morphological alterations may aid in evaluating the severity of pathological processes in intoxication with baclofen alone and in combination with ethanol and in determining the method of intoxication (baclofen alone or in combination with ethanol).

Airway inflammation in patients with bronchiectasis

Bronchiectasis is a chronic lung disease characterized by an abnormal dilation of the bronchial lumen caused by weakening or destruction of the muscle or elastic components of the bronchial wall, decreased mucous clearance and frequent infections of the respiratory tract. The golden standard for bronchiectasis diagnosis is high-resolution computed tomography (HRCT) of the chest. Inflammation holds a central role in the development of structural lung changes, as well as airway and lung parenchyma damage. Infection and colonization of the respiratory tract contribute to increased inflammation and further damage to the lung. Upon entry into the respiratory tract, the pathogens activate epithelial cells, macrophages and dendritic cells. Activated inflammatory cells secrete chemical mediators which activate the immune response and thus allow the phagocytosis of pathogens. Early diagnosis, appropriate treatment and interruption of the vicious circle between infection and inflammation in patients suffering from bronchiectasis, prevent the development of structural changes to the airways.

Recurrent hemoptysis caused by arteriovenous malformation

Pulmonary arteriovenous malformation is a rare disorder of pulmonary vascularization. We are going to describe the case of recurring hemoptysis with a patient who was diagnosed late with pulmonary AV malformation. The 68-yearold patient was hospitalized for the fourth time in the Clinic for Pulmonology, Clinical Center of Kragujevac due to recurring hemoptysis. Bronchoscopy was conducted which showed no signs of bleeding nor new changes in the bronchial lumen. MSCT of the chest eliminated the possibility of bronchiectasis as the cause for hemoptysis. Chest MSCT was repeated, and it was without evolutionary aspect when compared to the previous one. In April 2019, at the Military Medical Academy in Belgrade, the patient had bronchoscopy performed, the results were normal, and the examination was completed with exploration, along with selective angiography, where AV shunt could be seen on the left side. Since the diameter of the left bronchial artery was less than 2 mm, it was not possible to place the micro-catheter and do embolization, but hemostasis was done by manual compression, which lasted for 10 minutes. After six months of follow-up examinations, no complications were registered with the patient. The method of choice for diagnosing PAV malformation is bronchial angiography, while other chest radiographic methods are not reliable. Embolization is the method of choice for treating this disorder.

A rare and fatal respiratory disease: bronchial Dieulafoy’s disease

A 66-year-old woman had two severe episodes of massive hemoptysis without any premonitory symptoms, with approximately 400–500 ml blood each time. Bronchoscopic exam revealed a smooth and pulsatile protrusion that was approximately 8–10 mm in diameter found at the beginning of the right middle lobe bronchus in the bronchial lumen. The protrusion arose from the surface with absolutely normal mucosa. Selective bronchial arteriography showed that elongated, tortuous, and dilated branches of the bronchial artery in the region of the middle lobe bronchus. Further bronchial arterial embolization (BAE) is recommended, although the patient currently has no active bleeding. Bronchial Dieulafoy’s disease (BDD) is a rare and life-threatening disease. Selective bronchial arteriography is a diagnostic tool to detect and locate abnormal arteries. There is no unified guideline or expert consensus on the treatment of BDD. Selective BAE or surgical resection is usually used as a first-line treatment to control hemoptysis. The reviews of this paper are available via the supplemental material section.

Morpho-biochemical and immunohematologic features of calves infected with the agent of viral diarrhea

Тhe key direction of scientific research is considered to be the study of the characteristics of the course and manifestation of the disease, as well as the determination of virulent properties of pathogens. Calves infected with the agent of viral diarrhea were chosen as a model for study of the infectious process. The study summarizes the pathogenetic mechanisms of development and expression of viral diarrhea. Clinical, biochemical, and immunehematologic features of the disease were specified. data on morphological changes in parenchymal organs of diseased animals were found. Changes in protein, lipid, mineral metabolism, and electrolyte balance indices associated with increased activity of lactate dehydrogenase are considered to be metabolic features of VD. Immunologic research showed a shift in the process of lymphocyte differentiation with activation of the b-cell link of immunity and a decline in the phagocytic index. Calves infected with VD revealed signs of structural immunodeficiency, which is morphologically confirmed by the decrease of most of the lymphoid follicles of the spleen. The lungs displayed signs of catarrhal and purulent bronchitis, manifested by hyperplasia of the bronchial epithelium, desquamation of the epithelium and accumulation of exudate in the bronchial lumen and peribronchial edema. Evidence of serous lymphadenitis were registered in the lymph nodes associated with reduction of subcapsular lymphoid follicles, both in the subcapsular and central sinuses. They were accompanied by the growth of connective tissue in the stroma of the organ.

Expression Level of MiRNA-126 in Serum Exosomes of Allergic Asthma Patients and Lung Tissues of Asthmatic Mice

Background: To investigate MiRNA-126 amounts in serum exosomes from allergic asthma patients as well as lung tissues of asthmatic mice, evaluating the expression of its target gene DNMT1 in mouse specimens. Methods: MiRNA-126 amounts in serum exosomes from asthmatic patients were detected by real-time PCR. The mouse model of allergic asthma was established by OVA-sensitization, and allergic symptoms were recorded; serum IL-4 and sIgE level evaluation (ELISA), broncho alveolar lavage fluid (BALF) cell count and H&E staining were performed to assess airway inflammation. MiRNA-126 and DNMT1 levels in the lung of asthmatic and control mice were detected by real-time PCR; DNMT1 protein levels were detected by immunoblot. Results: MiRNA-126 amounts in peripheral blood exosomes from patients with allergic asthma were significantly higher than that of healthy volunteers (P<0.05). The frequencies of scratching of both sides of the nose and sneezing were elevated within 10 min of excitation in asthmatic rats compared with controls. Meanwhile, OVA-sIgE and IL-4 levels were significantly higher in asthmatic animals than controls (P<0.05). In the asthma group, narrowed bronchial lumen and thickened wall were observed, and bronchial and peripheral vessels showed overt inflammatory cell infiltration. Eosinophil, neutrophil and mast cell amounts in the BALF of asthmatic mice were significantly higher than control values. Furthermore, lung miRNA-126 expression in asthmatic mice was significantly higher than that of controls. Finally, DNMT1 mRNA and protein levels were significantly lower in asthmatic animals compared with controls (P < 0.01). Conclusion: MiRNA-126 is highly expressed in serum exosomes from allergic asthma patients and lung tissues of asthmatic mice, suggesting that it may be involved in the pathogenesis of bronchial asthma.