Gut Microbiota-Derived l-Histidine/Imidazole Propionate Axis Fights against the Radiation-Induced Cardiopulmonary Injury.

Radiation-induced cardiopulmonary injuries are the most common and intractable side effects that are entwined with radiotherapy for thorax cancers. However, the therapeutic options for such complications have yielded disappointing results in clinical applications. Here, we reported that gut microbiota-derived l-Histidine and its secondary metabolite imidazole propionate (ImP) fought against radiation-induced cardiopulmonary injury in an entiric flora-dependent manner in mouse models. Local chest irradiation decreased the level of l-Histidine in fecal pellets, which was increased following fecal microbiota transplantation. l-Histidine replenishment via an oral route retarded the pathological process of lung and heart tissues and improved lung respiratory and heart systolic function following radiation exposure. l-Histidine preserved the gut bacterial taxonomic proportions shifted by total chest irradiation but failed to perform radioprotection in gut microbiota-deleted mice. ImP, the downstream metabolite of l-Histidine, accumulated in peripheral blood and lung tissues following l-Histidine replenishment and protected against radiation-induced lung and heart toxicity. Orally gavaged ImP could not enter into the circulatory system in mice through an antibiotic cocktail treatment. Importantly, ImP inhibited pyroptosis to nudge lung cell proliferation after radiation challenge. Together, our findings pave a novel method of protection against cardiopulmonary complications intertwined with radiotherapy in pre-clinical settings and underpin the idea that gut microbiota-produced l-Histidine and ImP are promising radioprotective agents.

Risk factors and clinical features for post-transplant thoracic air-leak syndrome in adult patients receiving allogeneic haematopoietic stem cell transplantation.

Post-transplant thoracic air-leak syndrome (ALS) is rare but potentially life-threatening in patients receiving allogeneic haematopoietic stem cell transplantation (HSCT). Nevertheless, papers on thoracic ALS are limited, and this complication remains largely unknown. We reviewed 423 adult patients undergoing allogeneic HSCT from 2003 to 2014. Risk factors, clinical features and survival for thoracic ALS were collected and analysed. Thirteen out of 423 patients (3.1%) developed post-transplant thoracic ALS, including two ALS patients in the early phase. The median age at HSCT was 33 years among 13 patients with thoracic ALS. Male patients were predominant (69%). The median onset time was 253 days (range: 40-2680) after HSCT. Multivariate analysis revealed that grade III-IV acute graft-versus-host disease (GVHD) (p = 0.017), extensive chronic GVHD (cGVHD) (p = 0.019) and prior history of pulmonary invasive fungal infection (p = 0.007) were significant risk factors for thoracic ALS. In patients with cGVHD, those with thoracic ALS had a significantly worse survival than those without thoracic ALS (p = 0.04). Currently, published data analysing and exploring post-transplant thoracic ALS are limited. Our study employed a large patient cohort and determined the risk factors and clinical features for post-transplant thoracic ALS.

Metastatic abscess formation in a preexisting chest wall tumor: a rare initial presentation of Klebsiella pneumoniae liver abscess.

The common infectious agents in the chest wall include Mycobacterium tuberculosis, Actinomyces, fungi, Nocardia, Entamoeba histolytica, and other aerobes and anaerobes. Klebsiella pneumoniae is an uncommon etiological agent. We describe a case of ankylosing spondylitis in a 45-year-old man, who had exhibited a painless lump in the left posterior chest wall for 3 months and who presented with acute-onset pain, erythematous change, and fever in the 2 weeks before admission. Cultures of the blood and chest wall abscess both showed Gram-negative bacilli, which were classified as K. pneumoniae. A contrast-enhanced computed tomography scan of the abdomen revealed a nonenhancing cystic abscess measuring 4.9 × 6.5 × 6.4 cm in segment 6 of the liver and communicating with the chest wall. Drainage of the liver abscess under ultrasound guidance and open surgical drainage of the chest wall abscess combined with adequate antibiotic treatment resolved the abscess.

Pityrosporum ovale/orbiculare in papillomatous nevus cell nevi.

62% of 200 papillomatous nevus cell nevi compared to 45% of 40 seborrheic keratoses showed the presence of Pityrosporum ovale/orbiculare (Malassezia furfur) on their surface, supposedly representing a saprophytic state of the microorganisms in vivo. The papillomatous nevus cell nevi were of the compound or dermal type. Significant inflammation, dysplasia or major changes in color were absent. Electron microscopy revealed the characteristic, sometimes budding fungal cells. A relationship between the presence of Pityrosporum organisms and papillomatosis is discussed.