Yusuke Naito

Procalcitonin-guided antibiotic therapy in aspiration pneumonia and an assessment of the continuation of oral intake

BACKGROUND Procalcitonin-guided antibiotic therapy for community-acquired pneumonia is effective and safe. However, the usefulness of procalcitonin for aspiration pneumonia and its nutrition-related outcomes are unknown. METHODS We conducted a noninferiority randomized controlled study in patients with aspiration pneumonia who were admitted to our hospital between September 2010 and January 2012. We randomly assigned 105 patients to groups with different durations of antibiotic therapy based on the procalcitonin levels upon admission (procalcitonin group) or according to the standard guidelines (control group). The primary endpoints were relapse of aspiration pneumonia and death within 30 days, with a predefined noninferiority boundary of 10%. Secondary endpoints included duration of antibiotic exposure. Furthermore, we conducted a retrospective analysis of the prognostic factors that determined continuation of oral nutritional intake, relapse of pneumonia, and in-hospital death. RESULTS The rate of relapse and death within 30 days were similar in the procalcitonin and control groups (25% versus 37.5%; difference, -12.5%; 95% confidence interval, -30.9% to 5.9%). Procalcitonin-guided antibiotic therapy significantly shortened the median duration of antibiotic exposure (5 versus 8 days; p<0.0001); however, the continuation of oral intake was not increased (56% versus 50%; p=0.54). A multivariable analysis showed a significant association between the continuation of oral nutritional intake and the body mass index upon admission. CONCLUSIONS Procalcitonin-guided antibiotic therapy for aspiration pneumonia can shorten the duration of antibiotic exposure, but it does not increase the continuation of oral intake (UMIN000004800).

Endothelin B receptor-mediated encephalopathic events in mouse sepsis model.

AIMS We evaluated whether pathophysiological events in the brain in sepsis are mediated by ET-1/ETB receptor axis. MAIN METHODS We prepared raw fecal fluid from soft stool of mice. Mice were randomly divided into three groups: pre-PBS+raw fecal fluid group (Sepsis, easy stool method (ESM) group); pre-BQ788+raw fecal fluid group (BQ group); and pre-BQ788+PBS group (PBS group). According to each experimental condition, PBS or BQ788 was intravenously injected into mice prior to intraperitoneal administration of fecal fluid or PBS. All groups of mice were sacrificed at 8h after administration, and then brain samples were prepared. KEY FINDINGS In the ESM group, an increase of apoptotic neuroblasts was demonstrated in the subgranular zone of the hippocampal dentate gyrus, enhanced expression of c-FOS was observed in arginine-vasopressin-containing neurons in the hypothalamic paraventricular nucleus, and various cytokines involving TNF-α were upregulated in the brain, compared with those in the PBS group. In the region corresponding to their findings, the number of reactive microglia and vascular leakage was markedly increased. BQ788 inhibited the induction of c-FOS expression, neuroblast apoptosis, cytokine upregulation and reactive microglia without affecting vascular leakage. SIGNIFICANCE We demonstrated that BQ788 could protect the brain from the following sepsis-associated pathophysiological output: neural cell death, inflammatory response and the Hans Selyes environmental stress reaction.

Genetic and Pharmacological Inhibition of p38α Improves Locomotor Recovery after Spinal Cord Injury

One of the mitogen-activated protein kinases, p38α plays a crucial role in various inflammatory diseases and apoptosis of various types of cells. In this study, we investigated the pathophysiological roles of p38α in spinal cord injury (SCI), using a mouse model. Lateral hemisection at T9 of the SC was performed in wild type (WT) and p38α+/- mice (p38α-/- showed embryonic lethality). p38α+/- mice showed a better functional recovery from SCI-associated paralyzed hindlimbs compared to WT mice at 7 days post-injury (dpi), which remained until 28 dpi (an end time point of monitoring the behavior). In histopathological analysis at 28 dpi, there was more axonal regeneration with remyelination on the caudal side of the lesion epicenter in p38α+/- mice than in WT mice. At 7 dpi, infiltration of inflammatory cells into the lesion and expression of cytokines in the lesion were reduced in p38α+/- mice compared with WT mice. At the same time point, the number of apoptotic oligodendrocytes in the white matter at the caudal boarder of the lesion of p38α+/- mice was lower than that of WT mice. At 14 dpi, more neural and oligodendrocyte precursor cells in the gray matter and white matter, respectively, were observed around the lesion epicenter of p38α+/- mice compared with the case of WT mice. At the same time point, astrocytic scar formation was less apparent in p38α+/- than in WT mice, while compaction of inflammatory immune cells associated with the wound contraction was more apparent in p38α+/- than in WT mice. Furthermore, we verified the effectiveness of oral administration of SB239063, a p38α inhibitor on the hindlimb locomotor recovery after SCI. These results suggest that p38α deeply contributes to the pathogenesis of SCI and that inhibition of p38α is a beneficial strategy to recovery from SCI.

Idiopathic bronchocentric granulomatosis in an asthmatic adolescent.

Bronchocentric granulomatosis in asthmatic patients has been generally considered to be associated with allergic bronchopulmonary aspergillosis and represent a histopathologic manifestation of fungal hypersensitivity. Here we report a case of an idiopathic bronchocentric granulomatosis in a 17-year-old man with a history of asthma. He was admitted to the hospital with a fever and cough, and a chest CT scan showed peribronchial consolidation in the pulmonary parenchyma, which was unresponsive to antibiotic therapy. The pathological findings obtained by video-assisted thoracoscopic lung biopsy revealed necrotizing granulomatous inflammation centered on bronchi and bronchioles and there was no evidence of fungal colonization, resulting in a diagnosis of idiopathic bronchocentric granulomatosis. Systemic corticosteroid therapy led to clinical and radiological recovery. Physicians should take into account the possibility of the idiopathic process in bronchocentric granulomatosis of asthmatic patients.