Project description:Case presentationA 56-year-old man presented to the lung nodule clinic with abnormal chest imaging prompted by a chronic cough and hemoptysis. Approximately 2.5 years earlier, while kneeling beside his car fixing a flat tire, he fell backwards while holding the tire cap in his mouth, causing him to inhale sharply and aspirate the cap. He immediately developed an intractable cough productive of flecks of blood. He presented to an emergency room but left before being seen because of a long wait time and his lack of health-care insurance. He self-medicated for severe cough and chest discomfort with codeine, eventually developing a dependency. Approximately 3 weeks after aspirating the tire cap, his cough became productive, and he developed fever and chills. His symptoms improved transiently with antibiotics and additional narcotics. Ultimately, his chronic cough with intermittent hemoptysis affected his ability to work, and 30 months later he sought medical attention and was diagnosed with pneumonia and reactive airway disease. He was prescribed doxycycline, steroids, inhaled albuterol, and dextromethorphan, with initial improvement, but his symptoms recurred multiple times despite quitting smoking, leading to repeated medication courses.
Project description:With improvement in the diagnosis and treatment of cystic fibrosis cases in recent years, the survival of these cases has been increased. On the other hand, an increasing number of cases are presented during adulthood. Here we report a 24-year-old man with a history of productive cough, bilateral paranasal sinusitis and polyps, and recurrent abdominal pain. Thoracic computed tomography revealed a bilateral scattered tree in bud pattern and some bronchiectatic changes. Semen analysis showed azoospermia. A sweat chloride test was >60 mEq/l in two occasions.
Project description:Platelets (small, anucleate cell fragments) derive from large precursor cells, megakaryocytes (MKs), that reside in the bone marrow. MKs emerge from hematopoietic stem cells in a complex differentiation process that involves cytoplasmic maturation, including the formation of the demarcation membrane system, and polyploidization. The main function of MKs is the generation of platelets, which predominantly occurs through the release of long, microtubule-rich proplatelets into vessel sinusoids. However, the idea of a 1-dimensional role of MKs as platelet precursors is currently being questioned because of advances in high-resolution microscopy and single-cell omics. On the one hand, recent findings suggest that proplatelet formation from bone marrow-derived MKs is not the only mechanism of platelet production, but that it may also occur through budding of the plasma membrane and in distant organs such as lung or liver. On the other hand, novel evidence suggests that MKs not only maintain physiological platelet levels but further contribute to bone marrow homeostasis through the release of extracellular vesicles or cytokines, such as transforming growth factor β1 or platelet factor 4. The notion of multitasking MKs was reinforced in recent studies by using single-cell RNA sequencing approaches on MKs derived from adult and fetal bone marrow and lungs, leading to the identification of different MK subsets that appeared to exhibit immunomodulatory or secretory roles. In the following article, novel insights into the mechanisms leading to proplatelet formation in vitro and in vivo will be reviewed and the hypothesis of MKs as immunoregulatory cells will be critically discussed.
Project description:Ischaemic colitis typically presents with an acute abdominal pain and distension with bloody diarrhoea. However, this can vary and the condition is frequently missed or misdiagnosed, especially if the patient presents with chronic symptoms. Herein, we report a case of chronic presentation of ischaemic colitis in a 48-year-old man with a history of myocardial infarction. This report highlights the importance of having ischaemic colitis as a differential diagnosis whenever a patient with a history of arteriosclerosis presents with atypical chronic abdominal pain.