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European Journal of Pharmaceutical... May 2024In development of inhaled drugs- and formulations the measured concentration in the systemic circulation is often used as a surrogate for local dosimetry in the lungs....
BACKGROUND
In development of inhaled drugs- and formulations the measured concentration in the systemic circulation is often used as a surrogate for local dosimetry in the lungs. To further elucidate regional differences in the fate of drugs in the lungs, different aerodynamic sizes of aerosols have been used to target major airway regions. An alternative approach to achieve regional targeting of aerosols, is to use a defined aerosol bolus together with a bolus breath hold strategy. A small volume of test aerosol is intercalated and stopped at different penetration depths, to achieve increased drug deposition at chosen lung locations. Drug permeation from the lung regions is then investigated by repeatedly sampling venous blood from the systemic circulation. The PreciseInhale® (PI) exposure platform was developed to allow generation of aerosols from different sources, including clinical inhalers, into a holding chamber, for subsequent use with alternative exposure modules in vitro and in vivo. In the current first-in-human study was investigated the feasibility of a new clinical exposure module added to the PI system. By extracting aerosol puffs from a medical inhaler for subsequent delivery to volunteers, it was possible to administer whole lung exposures, as well as regional targeting exposures.
METHODS
Aerosols containing 250 µg/25 µg fluticasone propionate (FP)/salmeterol xinafoate (SMX) were automatically actuated and extracted from the pressurized Metered Dose Inhaler (pMDI) Evohaler Seretide forte into the PI system's holding chamber, then administered to the healthy volunteers using controlled flowrate and volume exposure cycles. Two main comparisons were made by measuring the systemic PK response: I. One label dose directly from the inhaler to the subject was compared to the same dose extracted from the pMDI into the PI system and then administered to the subject. II A small aerosol bolus at a penetration level in the central airways was compared to a small aerosol bolus at a penetration level in the peripheral lung.
RESULTS AND CONCLUSIONS
When one inhaler dose was administered via the PI system, the absorbed dose, expressed as AUC24, was approximately twice as high and the CV was less than half, compared to direct inhalation from the same pMDI. Bolus breath hold targeting of drugs from the same aerosol mixture to the peripheral lung and the central airways showed a difference in their appearance in the systemic circulation. Normalized to the same deposited dose, SMX had a 57 % higher C in the peripheral lung compared to the central airways. However, from 6 to 24 h after dosing the systemic concentrations of SMX from both regions were quite similar. FP had parallel concentrations curves with a 23 % higher AUC24 in the peripheral lung with no noticeable elevation around C. The permeability of these two substances from similar sized aerosols was indeed higher in the thinner air/blood barriers of the peripheral lung compared to the central airways, but differences as measured on the venous side of the circulation were not dramatic. In conclusion, the PI system provided better control of actuation, aspiration, and dispensation of aerosols from the clinical inhaler and thereby delivered higher quality read outs of pharmacokinetic parameters such as t, C, and AUC. Improved performance, using PI system, can likely also be employed for studying regional selectivity of other responses in the lungs, for use in drug development.
PubMed: 38460609
DOI: 10.1016/j.ejps.2024.106742 -
Cureus Mar 2024Metaplastic breast carcinoma (MBC) is very rare among all invasive breast carcinomas, accounting for less than 1.0% of them. MBCs are classified into five subtypes,...
Metaplastic breast carcinoma (MBC) is very rare among all invasive breast carcinomas, accounting for less than 1.0% of them. MBCs are classified into five subtypes, including mixed MBC - where the mix might be multiple metaplastic elements or a mixture of epithelial and mesenchymal elements. Overall survival for mixed MBC tends to correlate with a significantly worse outcome. Therefore, an early accurate diagnosis and surgical treatment for mixed MBCs must allow for an improved quality of life and better prognosis. However, there have not been many recently published papers describing the detailed cytological features of mixed MBCs on fine-needle aspiration (FNA) specimens. A 60-year-old female presented with a history of a hard breast mass on the left lateral side, showing an ill-defined and marginally enhanced tumor nodule on magnetic resonance imaging. The cytologic specimens of FNA contained a large number of three-dimensional, cohesive and sheet-like clusters, or non-cohesive single cells, of highly atypical spindled sarcomatoid to oval epithelioid cells having hyperchromatic pleomorphic nuclei and mitotic figures, in a necrotic and hemorrhagic background. A small amount of osteoid matrix-like substance was rarely seen, associated with a very small number of osteoclast-like giant cells. We first interpreted it as an invasive breast carcinoma of high grade. A mastectomy was performed, and a gross examination of the neoplasm revealed a hemorrhagic solid tumor lesion with a gray-whitish cut surface, measuring approximately 35 × 24 × 21 mm in diameter. On a microscopic examination, the tumor was predominantly composed of the proliferation of highly atypical oval to spindled cells predominantly in a sarcomatous growth fashion with focal production of chondroid and osteoid matrix, peripherally coexisted with a smaller volume of conventional invasive breast carcinoma. Immunohistochemistry showed that the sarcomatous tumor cells were specifically positive for vimentin, α-smooth muscle actin, or epithelial membrane antigen. Therefore, we finally made a diagnosis of invasive mixed MBC with heterologous mesenchymal differentiation and conventional adenocarcinomatous elements. To the best of our knowledge, this would most recently be the first case report of mixed MBC with heterologous mesenchymal differentiation and conventional adenocarcinomatous elements, with a focus on its FNA cytomorphologic findings. We should be aware that owing to its characteristic cytological features, cytopathologists might be able to make a correct diagnosis of MBC, based on multiple and adequate samplings.
PubMed: 38601424
DOI: 10.7759/cureus.55926 -
Respirology Case Reports Mar 2024Cryoprobes represent an option for bronchial foreign body removal in cases of bronchial obstruction due to viscous substances such as mochi at body temperature.
Cryoprobes represent an option for bronchial foreign body removal in cases of bronchial obstruction due to viscous substances such as mochi at body temperature.
PubMed: 38476667
DOI: 10.1002/rcr2.1322 -
The Journal of International Medical... Jun 2024A few cases have shown that bee stings can be linked to coronary stent thrombosis. However, instances of recurrent myocardial infarction resulting from bee stings among...
A few cases have shown that bee stings can be linked to coronary stent thrombosis. However, instances of recurrent myocardial infarction resulting from bee stings among patients who have successfully undergone revascularization treatment are rare. This case report describes a man in his early 60s who experienced an acute myocardial infarction. The left anterior descending coronary artery was revascularized by a drug-eluting stent. Just 1 week later, the patient experienced a second acute myocardial infarction and it occurred immediately after a bee sting. Angiography revealed stent thrombosis so thrombus aspiration was performed. Subsequently, the blood flow in the stent was unobstructed. Follow-up coronary angiography 1 year later revealed no signs of restenosis within the stent. Hymenoptera venoms contains thrombogenic substances that might lead to acute stent thrombosis.
Topics: Humans; Male; Myocardial Infarction; Insect Bites and Stings; Bees; Animals; Middle Aged; Coronary Angiography; Drug-Eluting Stents
PubMed: 38844785
DOI: 10.1177/03000605241259428 -
Respiration; International Review of... 2024Bronchopleural fistula (BPF) with empyema caused by severe necrotizing pulmonary infection is a complicated clinical problem that is often associated with poor general...
Inverted Placement of Endoscopic One-Way Endobronchial Valve Combined with Gelfoam in the Closure of Bronchopleural Fistula with Empyema in a Mechanically Ventilated Patient: A Case Report.
Bronchopleural fistula (BPF) with empyema caused by severe necrotizing pulmonary infection is a complicated clinical problem that is often associated with poor general condition so surgical interventions cannot be tolerated in most cases. Here, we present the successful management of multiple BPF with empyema in a mechanically ventilated patient with aspiration lung abscess. Occlusion utilizing Gelfoam followed by endobronchial valves (EBVs) implanted inverted via bronchoscope decreased the air leaking significantly and made intrapleural irrigation for empyema achievable and safe. This is the first report of a novel way of EBV placement and the combination use with other occlusive substances in BPF with empyema in a patient on mechanical ventilation. This method may be an option for refractory BPF cases with pleural infection.
Topics: Humans; Gelatin Sponge, Absorbable; Respiration, Artificial; Bronchial Fistula; Pleural Diseases; Empyema
PubMed: 38330927
DOI: 10.1159/000535478