Germline development during embryogenesis of the larvacean, Oikopleura dioica.

Germ cells develop into eggs and sperms and represent a lineage that survives through multiple generations. Germ cell specification during embryogenesis proceeds through one of two basic modes: either the cell-autonomous mode or the inductive mode. In the cell-autonomous mode, specification of germ cell fate involves asymmetric partitioning of the specialized maternal cytoplasm, known as the germplasm. Oikopleura dioica is a larvacean (class Appendicularia) and a chordate. It is regarded as a promising animal model for studying chordate development because of its short life cycle (5 days) and small genome size (∼60 â€‹Mb). We show that their embryos possess germplasm, as observed in ascidians (class Ascidiacea). The vegetal cytoplasm shifted towards the future posterior pole before the first cleavage occurred. A bilateral pair of primordial germ cells (PGC, B11 â€‹cells) was formed at the posterior pole at the 32-cell stage through two rounds of unequal cleavage. These B11 â€‹cells did not undergo further division before hatching of the tadpole-shaped larvae. The centrosome-attracting body (CAB) is a subcellular structure that contains the germplasm and plays crucial roles in germ cell development in ascidians. The presence of CAB with germplasm was observed in the germline lineage cells of larvaceans via electron microscopy and using extracted embryos. The CAB appeared at the 8-cell stage and persisted until the middle stage of embryogenesis. The antigen for the phosphorylated histone 3 antibody was localized to the CAB and persisted in the PGC until hatching after the CAB disappeared. Maternal snail mRNA, which encodes a transcription factor, was co-localized with the antigen for the H3S28p antibody. Furthermore, we found a novel PGC-specific subcellular structure that we call the germ body (GB). This study thus highlights the conserved and non-conserved features of germline development between ascidians and larvaceans. The rapid development and short life cycle (five days) of O. dioica would open the way to genetically analyze germ cell development in the future.

Protein phosphatase 2A is essential to maintain meiotic arrest, and to prevent Ca2+ burst at spawning and eventual parthenogenesis in the larvacean Oikopleura dioica.

Unfertilized eggs of most animals are arrested at a certain point in the meiotic cell cycles. Reinitiation of meiosis and the start of embryogenesis are triggered by fertilization. This arrest is essential for preventing parthenogenetic activation and for promoting proper initiation of development by fertilization. In the larvacean Oikopleura dioica, which is a simple model organism for studies of chordate development, the unfertilized egg is arrested at metaphase of meiosis I. We show here that protein phosphatase 2A (PP2A) is essential for maintenance of meiotic arrest after spawning of oocytes. Knockdown (KD) of the maternal PP2A catalytic subunit, which was found in functional screening of maternal factors, caused unfertilized eggs to spontaneously release polar bodies after spawning, and then start pseudo-cleavages without fertilization, namely, parthenogenesis. Parthenogenetic embryos failed to undergo proper mitosis and cytokinesis because of lack of a centrosome, which is to be brought into the egg by a sperm. Activation of the KD oocytes was triggered by possible rise of ambient and intracellular pH upon their release from the gonad into seawater at spawning. Live recording of intracellular calcium level of the KD oocytes indicated that the pH rise caused an aberrant Ca2+ burst, which mimicked the Ca2+ burst that occurs at fertilization. Then, the aberrant Ca2+ burst triggered meiosis resumption through Calcium/calmodulin-dependent protein kinase (CaMK II). Therefore, PP2A is essential for maintenance of meiotic arrest and prevention of parthenogenesis by suppressing the aberrant Ca2+ burst at spawning.

Impact of Sarcopenia on Surgical Outcomes in Non-small Cell Lung Cancer.

BACKGROUND: Sarcopenia influences overall survival (OS) and tumor progression in non-small cell lung cancer (NSCLC) patients. However, the impact of postoperative complications and the outcome of limited surgery have not been highlighted. Therefore, the aim of this study is to elucidate the prognostic impact of sarcopenia on surgical outcomes. PATIENTS AND METHODS: This study included NSCLC patients who had undergone lung cancer resection between 2007 and 2017. Sarcopenia was confirmed based on computed tomography of the cross-sectional area of the psoas muscle at the third lumbar vertebra level. We used propensity score-matched analysis to elucidate the impact of sarcopenia on postoperative complications and limited surgery. RESULTS: A total of 391 patients were enrolled, including 198 sarcopenic patients. Multivariate analysis showed that sarcopenia was an independent unfavorable prognostic factor associated with OS and recurrence-free survival [hazard ratio (HR), 3.33, P < 0.001; HR, 2.76, P < 0.001, respectively]. Regarding the incidence of postoperative complications, there was no difference between sarcopenic and nonsarcopenic patients (69/198 versus 55/193, P = 0.19). After propensity score matching, among patients without sarcopenia, the 5-year OS was lower in those with limited surgery than in those with standard surgery (70.7% vs. 96.4%, P = 0.011). In contrast, among sarcopenic patients, there was no difference in the 5-year OS between patients with limited surgery and those with standard surgery (53.2% vs. 60.7%, P = 0.66). CONCLUSIONS: Sarcopenia is a prognostic predictor for poor OS and may contribute to the selection of limited surgery for sarcopenic patients. Preoperative assessment of sarcopenia may provide clinically important information.

The Prognostic Impact of Pericardial Fat Volumes in Resected Non-small Cell Lung Cancer.

BACKGROUND: Pericardial fat (PF) has not been considered a prognostic biomarker for overall survival (OS) in lung cancer. This study was designed to elucidate the impact of PF on prognosis of resected non-small cell lung cancer patients. METHODS: We retrospectively reviewed a total of 349 patients who underwent lung resection and received high-resolution computed tomography in our institute. PF volume was calculated. PF extended vertically from the diaphragm to the bifurcation of the right main pulmonary artery. Propensity score matched analysis was used to compare OS between the high- and low-PF groups. RESULTS: PF volume increased according to body mass index (p < 0.001). Receiver operating characteristics (ROC) curve analysis for 3-year OS showed the possibility of better predictivity of PF than body-mass index (area under the curve, 0.66 vs. 0.61, p = 0.010). Cutoff level of PF volume was determined based on the ROC with 122 cm3. Five-year OS was poorer in the low-PF group (63.5% vs. 73.4%; p = 0.002). After propensity score matching, each group consisted of 89 cases. Five-year OS was poorer in the low-PF group (66.5% vs. 82.7%; p = 0.008). A Cox proportional hazards model showed low-PF volume was associated with poorer OS (hazard ratio, 2.14; p = 0.009). The number of respiratory-related deaths was higher in the low-PF group (10/89 vs. 2/89, p = 0.032). CONCLUSIONS: Low-PF volume may be associated with poor OS with an increase in the number of respiratory-related deaths. Patients with low-PF volume require careful follow-up after surgery.

Impact of Postoperative Pneumonia Developing After Discharge on Long-Term Follow-up for Resected Lung Cancer.

BACKGROUND: Postoperative nosocomial pneumonia is a common immediate complication following lung resection. However, the incidence and mortality of pneumonia developing after discharge (PDAD) for lung-resected patients during long-term observation remain unclear. The aim of this study was to investigate the clinical features of PDAD in patients with resected lung cancer. METHODS: We conducted a retrospective cohort study of 357 consecutive patients with lung cancer who had undergone lung resection at a single institution, between April 2007 and December 2016. The clinical characteristics, pathological features, and overall survival were analyzed. Propensity score matched analysis was used for the evaluation of overall survival between PDAD and non-PDAD groups with adjusted relevant confounding factors. RESULTS: PDAD was observed in 66 patients (18.5%). The cumulative incidence of PDAD was 14.9% at 3 years and 21.6% at 5 years. Mortality of PDAD was 30.3%. Multivariate analysis demonstrated that the risk factors for PDAD were age (OR 1.07; P = 0.005), oral steroid use (OR 5.62; P = 0.046), and lower-lobe resection (OR 1.87; P = 0.034). After propensity score matching, 52 patients with PDAD and 52 patients without it were compared. The incidence of PDAD resulted in a worse 5-year overall survival (56.1 vs. 69.3%; P = 0.024). The Cox proportional hazards model indicated that PDAD was associated with poor overall survival (HR 1.99, P = 0.027). CONCLUSIONS: Our findings revealed a high incidence and mortality of PDAD among patients who had undergone lung resection with long-term follow-up. Therefore, PDAD could be associated with poorer overall survival.

Modified whole-mount in situ hybridisation and immunohistochemistry protocols without removal of the vitelline membrane in the appendicularian Oikopleura dioica.

The appendicularian Oikopleura dioica is a planktonic chordate that retains a tadpole shape throughout its life. Its simple and transparent body, invariant cell lineages, fast development and available genome and transcriptome resources make it a promising model organism for research in developmental biology. However, large-scale analysis of gene expression in O. dioica is limited owing to the laborious and time-consuming process of manual removal of the vitelline membrane, because devitellinisation of pre-hatching embryos causes failure of normal development. Therefore, in this study, modified procedures were developed for whole-mount in situ hybridisation (WISH) and immunohistochemistry (WIHC). This protocol enables rapid mRNA or protein detection without a manual devitellination step for each specimen. The critical procedure is brief treatment of the vitelline membrane of living embryos with 0.05% actinase E before fixation. Two minutes of treatment was optimal for the penetration of antisense RNA probes and antibodies through the vitelline membrane. This WISH protocol was applicable for chromogenic and fluorescent tyramide signal amplification reactions. Using the new protocol, we found eight genes with tissue-specific expression in the tail muscle, trunk epidermis, heart, pharynx, oesophagus, stomach or gill openings of developing larvae. This procedure also allowed for the detection of exogenous FLAG-tagged histone-enhanced green fluorescent protein by WIHC using anti-FLAG antibody. This study provides a useful and convenient tool for studying spatial and temporal gene expression patterns in this simple chordate model and should facilitate handling large amounts of genetic data from transcriptome-based approaches and other techniques such as treatments with chemical inhibitors.

Bronchus sign on thin-section computed tomography is a powerful predictive factor for successful transbronchial biopsy using endobronchial ultrasound with a guide sheath for small peripheral lung lesions: a retrospective observational study.

BACKGROUND: Recent advances in bronchoscopy, such as transbronchial biopsy (TBB) using endobronchial ultrasonography with a guide sheath (EBUS-GS), have improved the diagnostic yield of small-sized peripheral lung lesions. In some cases, however, it is difficult to obtain adequate biopsy samples for pathological diagnosis. Adequate prediction of the diagnostic accuracy of TBB with EBUS-GS is important before deciding whether bronchoscopy should be performed. METHODS: We retrospectively reviewed 149 consecutive patients who underwent TBB with EBUS-GS for small-sized peripheral lung lesions (≤30 mm in diameter) from April 2012 to March 2013. We conducted an exploratory analysis to identify clinical factors that can predict an accurate diagnosis by TBB with EBUS-GS. All patients underwent thin-section chest computed tomography (CT) scans (0.5-mm slices), and the CT bronchus sign was evaluated before bronchoscopy in a group discussion. The final diagnoses were pathologically or clinically confirmed in all studied patients (malignant lesions, 110 patients; benign lesions, 39 patients). RESULTS: The total diagnostic yield in this study was 72.5% (95% confidence interval: 64.8-79.0%). Lesion size, lesion visibility on chest X-ray, and classification of the CT bronchus sign were factors significantly associated with the definitive biopsy result in the univariate analysis. In the multivariate analysis, only the CT bronchus sign remained as a significant predictive factor for successful bronchoscopic diagnosis. The CT bronchus sign was also significantly associated with the EBUS findings of the lesions. CONCLUSION: Our results suggest that the CT bronchus sign is a powerful predictive factor for successful TBB with EBUS-GS.

Examining How Interaural Differences Owing to Head Rotation during Walking Improve the Distance of Auditory Obstacle Perceptions among Individuals with Visual Impairment: A Case Study in Small-Scale Blind Group.

The ability of individuals with visual impairment to recognize an obstacle by hearing is called "obstacle sense". This ability is facilitated while they are moving, though the exact reason remains unknown. This study aims to clarify which acoustical factors may contribute to obstacle sense, especially obstacle distance perception. First, we conducted a comparative experiment regarding obstacle distance localization by individuals who are blind (N = 5, five men with blindness aged 22-42 (average: 29.8)) while they were standing and walking. The results indicate that the localized distance was more accurate while walking than while standing. Subsequently, the head rotation angle while walking and acoustic characteristics with respect to obstacle distance and head rotation angle were investigated. The peaks of the absolute head rotation angle during walking ranged from 2.78° to 11.11° (average: 6.55°, S.D.: 2.05°). Regarding acoustic characteristics, acoustic coloration occurred, and spectral interaural differences and interaural intensity differences were observed in the blind participants (N = 4, four men including two blind and two control sighted persons aged 25-38 (average: 30.8)). To determine which acoustic factors contribute, we examined the threshold of changes for interaural differences in time (ITD) and intensity (IID) (N = 11, seven men and four women with blindness aged 21-35 (average: 27.4)), as well as coloration (ICD) (N = 6, seven men and a woman with blindness aged 21-38 (average: 29.9))-depending on the head rotation. Notably, ITD and IID thresholds were 86.2 µs and 1.28 dB; the corresponding head rotation angles were 23.5° and 9.17°, respectively. The angle of the ICD threshold was 6.30° on average. Consequently, IID might be a contributing factor and ICD can be utilized as the cue facilitating the obstacle distance perception while walking.

Aqueous fraction of Sauropus androgynus might be responsible for bronchiolitis obliterans.

BACKGROUND AND OBJECTIVE: Bronchiolitis obliterans (BO) has been reported to develop following ingestion of Sauropus androgynus (SA), a leafy shrub distributed in Southeast Asia. Little is known about direct effects of SA on airway resident cells or haematopoietic cells in vitro. Identification of the SA component responsible for the development of BO would be an important key to elucidate its mechanism. We sought to elucidate the direct effects of SA on airway resident cells or haematopoietic cells and identify the SA element responsible for the pathogenesis of BO. METHODS: SA dry powder was partitioned into fractions by solvent extraction. Human and murine monocytic cells, epithelial cells and endothelial cells were cultured with SA solution or fractions eluted from SA. We also investigated the effect of SA in vivo using a murine BO syndrome (BOS) model. RESULTS: The aqueous fraction of SA induced significant increases of inflammatory cytokine and chemokine production from monocytic lineage cells. This fraction also induced significant apoptosis of endothelial cells and enhanced intraluminal obstructive fibrosis in allogeneic trachea allograft in the murine BOS model. We found individual differences in tumour necrosis factor α (TNF-α) production from monocytes of healthy controls stimulated by this aqueous fraction of SA, whereas it induced high-level TNF-α production from monocytes of patients with SA-induced BO. CONCLUSIONS: These results suggest that an aqueous fraction of SA may be responsible for the pathogenesis of BO.

Endothelial-mesenchymal transition in bleomycin-induced pulmonary fibrosis.

The pathological hallmark lesions in idiopathic pulmonary fibrosis are the fibroblastic foci, in which fibroblasts are thought to be involved in the tissue remodeling, matrix deposition, and cross-talk with alveolar epithelium. Recent evidence indicates that some fibroblasts in fibrosis may be derived from bone marrow progenitors as well as from epithelial cells through epithelial-mesenchymal transition. To evaluate whether endothelial cells could represent an additional source for fibroblasts, bleomycin-induced lung fibrosis was established in Tie2-Cre/CAG-CAT-LacZ double-transgenic mice, in which LacZ was stably expressed in pan-endothelial cells. Combined X-gal staining and immunocytochemical staining for type I collagen and alpha-smooth muscle actin revealed the presence of X-gal-positive cells in lung fibroblast cultures from bleomycin-treated mice. To explore the underlying mechanisms, by which loss of endothelial-specific markers and gain of mesenchymal phenotypes could be involved in microvascular endothelial cells, the effects of activated Ras and TGF-beta on the microvascular endothelial cell line MS1 were analyzed. Combined treatment with activated Ras and TGF-beta caused a significant loss of endothelial-specific markers, while inducing de novo mesenchymal phenotypes. The altered expression of these markers in MS1 cells with activated Ras persisted after withdrawal of TGF-beta in vitro and in vivo. These findings are the first to show that lung capillary endothelial cells could give rise to significant numbers of fibroblasts through an endothelial-mesenchymal transition in bleomycin-induced lung fibrosis model.

Erythromycin-induced CXCR4 expression on microvascular endothelial cells.

Although stromal-derived factor-1 (SDF-1) via its cognate receptor CXCR4 is assumed to play a critical role in migration of endothelial cells during new vessel formation after tissue injury, CXCR4 expression on endothelial cells is strictly regulated. Erythromycin (EM), a 14-membered ring macrolide, has an anti-inflammatory effect that may account for its clinical benefit in the treatment of chronic inflammatory diseases. However, the effects of EM on endothelial cells and especially their expression of CXCR4 have not been fully evaluated. In this study, we demonstrated that EM markedly induced CXCR4 surface expression on microvascular endothelial cells in vitro and lung capillary endothelial cells in vivo. This ability to induce CXCR4 surface expression on endothelial cells was restricted to 14-membered ring macrolides and was not observed in other antibiotics including a 16-membered ring macrolide, josamycin. Furthermore, this EM-induced expression of CXCR4 on endothelial cells was functionally significant as demonstrated by chemotaxis assays in vitro. These findings suggest that EM-induced CXCR4 surface expression on endothelial cells may promote migration of CXCR4-expressing endothelial cells into sites of tissue injury, which may be associated with the known anti-inflammatory activity of this macrolide.

Long-term impact of complications after lung resections in non-small cell lung cancer.

BACKGROUND: Postoperative complications after lung resection are common and fatal. The immediate effects of postoperative complications are related to poor prognosis; however, the long-term effects have not been assessed. Thus, this investigation aimed to clarify the long-term effects of postoperative complications among patients with resected non-small cell lung cancer (NSCLC). METHODS: This retrospective cohort study included 345 patients with resected NSCLC from a single institution. We used the Clavien-Dindo classification to classify postoperative complications. Postoperative complications were defined as complications with a Clavien-Dindo grade of ≥2. The Kaplan-Meier method was used to evaluate survival. Prognostic factors were analyzed using a Cox proportional hazard model. RESULTS: There were 110 patients with postoperative complications (31.9%). The 5-year overall survival (OS), recurrence-free survival (RFS), and cause-specific survival (CSS) rates were significantly lower in patients with complications than in those without complications [OS: 66.1%, 95% confidence interval (CI): 55.4-74.8% vs. 78.0%, 95% CI: 71.8-83.1%, P=0.001; RFS: 48.8%, 95% CI: 38.1-58.7% vs. 70.8%, 95% CI: 64.2-76.4%, P<0.001; CSS: 82.7%, 95% CI: 72.8-89.3% vs. 88.2%, 95% CI: 82.8-92.0%, P=0.005]. The 5-year OS was lower in the pulmonary complication group than in the other complication group (58.1%, 95% CI: 40.0-72.4% vs. 70.5%, 95% CI: 56.6-80.6%, P=0.033). Postoperative complications were indicated as a poor prognostic factor for OS (hazard ratio, 1.67; 95% CI: 1.11-2.53; P=0.002). CONCLUSIONS: Postoperative complications were associated with unfavorable OS because of the worse prognosis of postoperative pulmonary complications.

Postoperative C-reactive Protein Is a Predictive Biomarker for Survival After Non-small Cell Lung Cancer Resection.

BACKGROUND/AIM: Preoperative C-reactive protein (CRP) is well recognized as a prognostic factor of non-small cell lung cancer (NSCLC). The present study aimed to elucidate the prognostic impact of postoperative CRP in patients with NSCLC following lung resection. PATIENTS AND METHODS: We retrospectively reviewed 336 patients with NSCLC treated with lung resection. CRP levels were measured at postoperative week 6 (CRP6w; range: 4-8 weeks). Patients were divided into two groups based on CRP6w median value (5.0 mg/l); the 5-year overall survival (OS) as well as the recurrence-free survival (RFS) was evaluated in both groups. RESULTS: Five-year OS and RFS were worse in the high-CRP6w group than in the low-CRP6w group (62.9% vs. 82.9%; p<0.001, 48.4% vs. 76.1%; p<0.001, respectively). Subgroup analysis for pathological stage I and ≥II also revealed worse OS in the high-CRP6w group. Multivariate analysis revealed an association between high CRP6w and worse OS (hazard ratio, 2.23; p<0.001). CONCLUSION: CRP6w may serve as a prognostic biomarker in patients with resected NSCLC.

Prognostic Impact of Postoperative C-reactive Protein for Non-small Cell Lung Cancer Following Lobectomy.

BACKGROUND/AIM: C-reactive protein (CRP) is associated with cancer progression; however, the prognostic impact of postoperative CRP remains controversial. The aim of this study was to investigate the prognostic significance of postoperative CRP in patients with resected non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: A total of 198 consecutive patients with NSCLC that had undergone lobectomy were retrospectively reviewed. CRP was measured on postoperative days 1, 3, and 5. Patients were divided into two groups according to the median of CRP on postoperative day 3 (CRP3); the high and low CRP3 groups (n=99, respectively). RESULTS: Five-year overall survival was significantly higher in the high CRP3 group than the low CRP3 (75.3% vs. 86.5%; p=0.016), as was the 5-year recurrence-free survival (62.7% vs. 73.0%; p=0.016). Multivariate analysis revealed that high CRP3 was associated with a favorable prognosis (hazard ratio(HR)=0.36; p<0.001). CONCLUSION: High CRP3 may be a favorable prognostic predictor in patients with NSCLC following lobectomy.

Impact of the favorable prognosis of patients with lung cancer adjoining bullae.

BACKGROUND: Lung cancer adjoining bullae (LC-AB) is an uncommon manifestation. The clinical characteristics and prognosis of LC-AB remain unclear. The aim of this study is to investigate the clinical features and overall survival (OS) of patients with LC-AB following lung resection compared to non-LC-AB group. METHODS: We retrospectively investigated 291 consecutive patients with lung cancer who underwent curative resection in a single institution between April 2007 and March 2015. A total of LC-AB was 52 patients. LC-AB was determined using thin slice computed tomography (CT) imaging and pathological findings. Survival analysis was calculated using the Kaplan-Meier method. We used a Cox proportional hazards model for the univariate and multivariate analysis to identify prognostic factors. RESULTS: The LC-AB group showed a higher frequency of younger patients (P=0.017), former or current smokers (P=0.011), men (P=0.021), tumor location in the upper lobe (P=0.031), moderately or poorly differentiated tumor histology (P<0.001), pleural indentation (P=0.007), and non-adenocarcinoma histology (P=0.016) than the non-LC-AB group. The 5-year survival and recurrence-free survival (RFS) rates were significantly higher in the LC-AB group than the non-LC-AB group (88.5% vs. 74.9%, P=0.010, 75.4% vs. 61.3%, P=0.030, respectively). Multivariate analysis using a Cox proportional hazard model of OS showed that LC-AB was an independent prognostic factor [hazard ratio (HR): 0.30, 95% confidence interval (CI): 0.12-0.77, P=0.012]. CONCLUSIONS: Patients with LC-AB had better OS than those with non-LC-AB. Thus, LC-AB may be an independent favorable prognostic factor following curative resection.

DNA interference-mediated screening of maternal factors in the chordate Oikopleura dioica.

The maternal contribution to the oocyte cytoplasm plays an important role during embryogenesis because it is involved in early cell fate specification and embryonic axis establishment. However, screening projects targeting maternal factors have only been conducted in a limited number of animal models, such as nematodes, fruit flies, and zebrafish, while few maternal genes have been analysed because of difficulties encountered in inhibiting gene products already expressed in the ovaries. Therefore, simple and efficient methods for large-scale maternal screening are necessary. The appendicularian Oikopleura dioica is a planktonic tunicate member of the chordates. Gonadal microinjection and a novel gene knockdown method, DNA interference (DNAi), have been developed for use in this animal with the aim of inhibiting gene functions during oogenesis within the gonad. In this study, we adapted these methods for large-scale maternal factor screening, and observed malformation phenotypes related to some maternal factors. Approximately 2000 (56.9%) ovary-enriched gene products were screened, of which the knockdown of seven encoding genes resulted in various abnormalities during embryonic development. Most of these were related to microtubules and cell adhesion-related proteins. We conclude that DNAi is a potentially powerful screening tool for the identification of novel maternal factors in chordates.

Metastatic squamous cell carcinoma of the lung mimicking multiple bone abscesses.

Squamous cell carcinoma of the lung is known to metastasize to the bones, but a presentation similar to bone abscess is rare. We encountered a case with bone metastases that mimicked bone abscess, which delayed the diagnosis of squamous cell lung carcinoma. A 67-year-old man presented with a left upper lung infiltrate and lytic lesions on the left first rib and right fifth rib. In consideration of a possible infectious process, cultures of the aspirate from the right fifth rib lesion and blood were taken; however, results were non-specific. Thereafter, bronchoscopic biopsy of the left upper lung nodule and ultrasound-guided biopsy of the right fifth rib lesion yielded a diagnosis of squamous cell lung carcinoma with bone metastases. Metastatic squamous cell lung carcinoma may have imaging characteristics of bone abscess and should be considered in the differential diagnosis of such lesions.

[Moderately differentiated adenocarcinoma of the lung presenting as multiple pulmonary metastases with thin-walled cavities].

A 63-year-old woman was admitted because of diabetes mellitus and abnormal chest radiographic findings. Computed tomographic scan showed a large mass in the S1 region of the right lung and many pulmonary nodules with thin-walled cavities in both lung fields. A transbronchial biopsy specimen revealed moderately differentiated adenocarcinoma of bronchial gland origin. The patient could not receive systemic chemotherapy because of her poor physical status, and died of respiratory failure due to advanced pulmonary metastases. Histopathological examination of an autopsy specimen confirmed the diagnosis of primary bronchial adenocarcinoma with multiple cavitary metastases. The cavity wall consisted of moderately differentiated adenocarcinoma cells, and central necrosis with neutrophil infiltration and fibrin precipitation were recognized. These findings suggest that the mechanism of cavity formation in this case may depend on the ischemic tumor necrosis or colliquative tumor necrosis associated with neutrophil infiltration into the central portion of metastatic lesion.

Three Adult Cases of HPV-B19 Infection with Concomitant Leukopenia and Low Platelet Counts.

We encountered three adult patients with flu-like symptoms diagnosed with human parvovirus B19 (HPV-B19) infection. Blood serum analysis also revealed leukopenia, with white blood cell counts (WBCs) of 1,000-2,000/mL and low platelet counts of 89-150 × 10(9)/L. Typical skin rash was absent in one patient. Bone marrow examination of another patient showed hypoplastic marrow with <5% blast cells. All patients recovered without administration of granulocyte colony-stimulating factor (G-CSF). Therefore, HPV-B19 infection with leukopenia should be considered in adult patients with leukopenia during erythema infectiosum epidemics, even if typical clinical findings (ie, skin rash) are absent. Further, the fact that three cases were observed over the stated time period at our hospital, which is located in Nagoya city, showed a transition to a slightly higher level of incidence than the annual average.

Gonococcal endocarditis in a 47-year-old Japanese man.

A 47-year-old sexually active Japanese man was admitted with a persistent fever and weight loss. A physical examination revealed a cardiac murmur. A transthoracic echocardiogram was nondiagnostic, although blood cultures grew Neisseria gonorrhoeae. Gonococcal endocarditis was diagnosed based on the modified Duke criteria. The administration of antimicrobial therapy resulted in an adequate initial resolution; however, two months after completing the therapy, the patient developed cardiac failure. Severe aortic regurgitation was identified, and the patient underwent emergent aortic valve replacement. Despite the rarity of gonococcal endocarditis, this disease should nevertheless be considered in patients presenting with a fever, cardiac murmur and a consistent sexual history.