The clinical impact of preoperative body composition differs between male and female colorectal cancer patients

AIM

Patient body composition is an important indicator of metabolic status and is associated with cancer progression. Because body composition varies between men and women, we aimed to examine the difference in clinical impact of preoperative body composition according to sex.

METHOD

We used an integrated dataset of 559 colorectal cancer (CRC) patients. The association between preoperative body composition indices [body mass index (BMI), visceral to subcutaneous fat area ratio (VSR) and skeletal muscle index (SMI)] and patient outcome, clinicopathological factors and preoperative inflammation and nutritional status was analysed, comparing men and women.

RESULTS

Preoperative low BMI and low SMI in men was significantly associated with unfavourable overall survival (OS) [BMI: hazard ratio (HR) 2.22, 95% CI 1.28-4.14, P = 0.004; SMI: HR 2.54, 95% CI 1.61-4.07, P < 0.001] and high VSR in women was significantly associated with unfavourable OS (HR 1.79, 95% CI 1.03-3.02, P = 0.040). Additionally, low SMI in men was significantly associated with deeper tumour invasion and greater distant metastasis and high VSR in women was significantly associated with advanced age, right-sided tumour, lower total lymphocyte count and lower albumin levels. Interestingly, low BMI in men was significantly associated with deeper tumour invasion, but also with favourable inflammation and nutritional status (lower C-reactive protein and higher albumin).

CONCLUSION

The clinical impact of preoperative body composition differed between men and women: SMI in men and VSR in women were good prognosticators. Our findings may provide a novel insight for CRC treatment strategies.

Platelet count and mean platelet volume are associated with not only bone, soft tissue, and lymph node metastases but also with malignant pleural effusion in lung cancer patients

An increased platelet count is often observed in lung cancer patients. Whether and how the platelets affect cancer progression have yet to be established. The aim of the study was to investigate the involvement of the platelet count and mean platelet volume (MPV) in the prognosis and progression of lung cancer patients. This retrospective study included 146 patients with newly diagnosed primary lung cancer. The platelet count and MPV were measured before invasive diagnostic procedures and treatment. These platelet indices, overall survival of the patients, and tumor metastases for each organ were analyzed. On Kaplan-Meier survival analysis, the overall survivals of patients with platelet counts ≤ 244.0 × 109/L or MPV > 9.7 fL were longer than those of patients with platelet counts > 244.0 × 109/L or MPV ≤ 9.7 fL. Cox regression analysis showed that poor performance status, increased platelet count, and increased C-reactive protein were independent prognostic factors. The platelet indices were associated with metastases to bone, soft tissue, and lymph node, in addition to malignant pleural effusion. Increased platelet count and decreased MPV were unfavorable prognostic factors for patients with lung cancer, and they were involved in bone, soft tissue, and lymph node metastases and malignant pleural effusion.

The impact of preoperative anaemia and anaemic subtype on patient outcome in colorectal cancer

AIM

Preoperative anaemia is associated with adverse outcomes in colorectal cancer (CRC). To clarify the reason for this we aimed to comprehensively assess the association of preoperative anaemia with tumour characteristics, host systemic inflammation and nutrition status, and perioperative blood transfusion.

METHOD

We used an integrated database of 592 CRC patients. The association of preoperative anaemic subtype, calculated from haemoglobin and erythrocyte mean corpuscular volume levels, with patient outcome, preoperative serum data relating to systemic inflammation and nutrition and perioperative blood transfusion was analysed.

RESULTS

Preoperative anaemia was significantly associated with poorer overall survival and relapse-free survival (RFS); in particular microcytic anaemia had a trend to poorer RFS than other forms of anaemia (P = 0.0648). In addition, preoperative anaemia was significantly correlated with right-sided tumours, greater depth of tumour invasion, use of neoadjuvant chemotherapy, poorer prognostic nutritional index and higher modified Glasgow Prognostic Score (mGPS). Microcytic anaemia in particular had a strong association with a greater depth of tumour invasion (P = 0.0072) and higher mGPS (P = 0.0058) than other causes of anaemia. Perioperative blood transfusion for CRC patients with anaemia was associated with adverse outcomes.

CONCLUSIONS

Preoperative anaemia, especially microcytic anaemia, was associated with poor patient outcomes, possibly due to poor systemic inflammatory and nutritional status, and it was not improved by perioperative blood transfusion. Our data suggest that preoperative anaemia and the anaemic subtype may serve as an easily available predictor of outcome in CRC.

Minimally invasive esophagectomy may contribute to long-term respiratory function after esophagectomy for esophageal cancer

Evidence suggests that minimally invasive esophagectomy has several advantages with regard to short-term outcomes, compared to open esophagectomy in esophageal cancer patients. However, the impact of minimally invasive esophagectomy on long-term respiratory function remains unknown. The objective of this study is to assess the association between use of the minimally invasive esophagectomy and long-term respiratory dysfunction in esophageal cancer patients after esophagectomy. This retrospective single institution study using prospectively collected data included 87 consecutive esophageal cancer patients who had undergone esophagectomy. All patients underwent a respiratory function test before, and one year after esophagectomy. Logistic regression analysis was used to compute the hazard ratio for long-term respiratory dysfunction. Minimally invasive esophagectomies were performed in 53 patients, and open esophagectomies in 34 patients. The two groups showed no significant differences in terms of postoperative complications and postoperative course. Nor were any differences observed between the two groups in terms of volume capacity (L) and forced expiratory volume 1.0 (L) before esophagectomy (P > 0.34). However, one year after esophagectomy, the decreases in volume capacity and forced expiratory volume 1.0 were significantly less in the minimally invasive esophagectomy group than in the open esophagectomy group (P = 0.04 and P = 0.007, respectively). Multivariate analyses revealed that minimally invasive esophagectomy was an independent favorable factor for maintenance of forced expiratory volume 1.0 (hazard ratio = 0.17, 95% confidence interval 0.04-0.71; P = 0.01). Minimally invasive esophagectomy may be an independent favorable factor for maintenance of long-term respiratory function in esophageal cancer patients after esophagectomy.

Monitoring sputum culture in resected esophageal cancer patients with preoperative treatment

Pneumonia is a major cause of postesophagectomy mortality and worsens the long-term survival in resected esophageal cancer patients. Moreover, preoperative treatments such as chemotherapy or chemoradiotherapy (which have recently been applied worldwide) might affect the bacterial flora of the sputum. To investigate the association among preoperative treatments, the bacterial flora of sputum, and the clinical and pathological features in resected esophageal cancer patients, this study newly investigates the effect of preoperative treatments on the bacterial flora of sputum. We investigated the association among preoperative treatments, the bacterial flora of sputum, and clinical and pathological features in 163 resected esophageal cancer patients within a single institution. Pathogenic bacteria such as Candida (14.1%), Staphylococcus aureus (6.7%), Enterobacter cloacae (6.1%), Haemophilus parainfluenzae (4.9%), Klebisiella pneumoniae (3.7%), Methicillin-resistant Staphylococcus aureus (MRSA) (3.7%), Pseudomonas aeruginosa (2.5%), Escherichia coli (1.8%), Streptococcus pneumoniae (1.8%), and Haemophilus influenzae (1.2%) were found in the sputum. The pathogen detection rate in the present study was 34.3% (56/163). In patients with preoperative chemotherapy and chemoradiotherapy, the indigenous Neisseria and Streptococcus species were significantly decreased (P= 0.04 and P= 0.04). However, the detection rates of pathogenic bacteria were not associated with preoperative treatments (all P> 0.07). There was not a significant difference of hospital stay between the sputum-monitored patients and unmonitored patients (35.5 vs. 49.9 days; P= 0.08). Patients undergoing preoperative treatments exhibited a significant decrease of indigenous bacteria, indicating that the treatment altered the bacterial flora of their sputum. This finding needs to be confirmed in large-scale independent studies or well-designed multicenter studies.

Measurement of neutral gas pressure in the D-module of GAMMA 10/PDX by using ASDEX type fast ionization gauge

In the divertor simulation experiments in the GAMMA 10/PDX tandem mirror, pressure of the neutral gas was investigated by using a fast ionization gauge. The gauge was absolutely calibrated for hydrogen gas by using a capacitance manometer. Change of the gauge sensitivity due to the magnetic field of GAMMA 10/PDX was also evaluated. The typical gas pressure measured in detached plasma experiments was 0.1-10 Pa. The degree of plasma detachment determined from the reduction of heat flux was enhanced as the gas pressure increases. Rapid increase of the gas pressure under the plasma flow was also observed.

Prognostic and clinical impact of sarcopenia in esophageal squamous cell carcinoma

Recently, depletion of skeletal muscle mass (sarcopenia) has been linked to poor prognosis in several types of cancers, but has not been investigated in esophageal squamous cell carcinoma (ESCC). This retrospective study investigates the relationship between sarcopenia and clinical outcome in ESCC patients treated by surgical resection or definitive chemoradiation therapy (dCRT). The study was retrospectively conducted in a single academic hospital in Kumamoto, Japan, and involved 325 ESCC patients (256 surgical cases and 69 dCRT cases) treated between April 2005 and April 2011. Skeletal muscle mass was quantified by radiologic measures using standard computed tomography scans. The skeletal muscle tissue in the 325 ESCC patients was distributed as follows: mean: 47.10; median: 46.88; standard deviation (SD): 7.39; range: 31.48-71.11; interquartile range, 46.29-47.90. Skeletal muscle tissue was greater in male patients than in female patients (P < 0.0001), but was independent of other clinical and tumor features. Sarcopenia was not significantly associated with overall survival (log rank P = 0.54). Lymph node involvement significantly altered the relationship between sarcopenia and survival rate (P for interaction = 0.026). Sarcopenia significantly reduced the overall survival of patients without lymph node involvement (log rank P = 0.035), but was uncorrelated with overall survival in patients with lymph involvement (log rank, P = 0.31). The anastomosis leakage rate was significantly higher in the sarcopenia group than in the non-sarcopenia group (P = 0.032), but other surgical complications did not significantly differ between the two groups. Sarcopenia in ESCC patients without lymph node involvement is associated with poor prognosis, indicating sarcopenia as a potential biomarker for identifying patients likely to experience an inferior outcome. Moreover, sarcopenia was associated with anastomosis leakage but no other short-term surgical outcome.

Toll-like receptor 2-mediated modulation of growth and functions of regulatory T cells by oral streptococci

This study was designed to determine whether oral streptococci modulate the growth and functions of regulatory T cells. Heat-killed cells of wild-type strains of Streptococcus gordonii and Streptococcus mutans induced the Toll-like receptor 2 (TLR2) -mediated nuclear factor-κB (NF-κB) activation, but their lipoprotein-deficient strains did not. Stimulation with these streptococci resulted in a significant increase in the frequency of CD4(+) CD25(+) Foxp3(+) regulatory T cells in splenocytes derived from both TLR2(+/+) and TLR2(-/-) mice, but the level of increase in TLR2(+/+) splenocytes was stronger than that in TLR2(-/-) splenocytes. Both strains of S. gordonii enhanced the proliferation of CD4(+) CD25(+) Foxp3(+) regulatory T cells isolated from TLR2(+/+) mice at the same level as those from TLR2(-/-) mice in an interleukin-2-independent manner. However, wild-type and lipoprotein-deficient strains of both streptococci did not enhance the suppressive activity of the isolated regulatory T cells in vitro, but rather inhibited it. TLR ligands also inhibited the suppressive activity of the regulatory T cells. Inhibition of the suppressive activity was recovered by the addition of anti-IL-6 antibody. Pretreatment of antigen-presenting cells with the NF-κB inhibitor BAY11-7082 enhanced the suppressive activity of the regulatory T cells. These results suggested that interleukin-6 produced by antigen-presenting cells inhibits the suppressive activity of the regulatory T cells. Wild-type strain, but not lipoprotein-deficient strain, of S. gordonii reduced the frequency of CD4(+)  CD25(+)  Foxp3(+) regulatory T cells in the acute infection model, whereas both strains of S. gordonii increased it in the chronic infection model mice. Hence, this study suggests that oral streptococci are capable of modulating the growth and functions of regulatory T cells in vitro and in vivo.

[Pericardiectomy for post-coronary artery bypass grafting constrictive pericarditis; strategy for safe and complete pericardiectomy]

Surgery for constrictive pericarditis after coronary artery bypass grafting (CABG) needs complete pericardiectomy without injury to bypass grafts. We performed pericardiectomy for post-CABG constrictive pericarditis 15 months after the first surgery. Preoperative multislice helical 3-dimensional computed tomography (CT) clearly demonstrated the patent bypass grafts and anatomical relationship between grafts and surrounding organs. Among surgical approaches, we chose bilateral thoracotomy to avoid injury to the bypass grafts and to obtain a good surgical exposure, especially for pericardiectomy of the left side of the heart. Additionally, with the use of intraoperative doppler ultrasound blood flowmetry, we could safely achieve complete pericardiectomy. We conclude that the combined application of 3-dimensional CT, bilateral thoracotomy and doppler ultrasound blood flowmetry was a supreme strategy for the operation of constrictive pericarditis after CABG.

[Management of myasthenia gravis in association with thymoma]

From June 1975 to March 2002, we experienced 339 patients with myasthenia gravis (MG). Ninety-four patients (81 generalized MG and 13 ocular type) had associated with thymoma. Extended thymectomy including thymoma was performed in all patients. The thymomas were classified as stage I (n = 46), II (n = 31), III (n = 14), and IV a (n = 3). Histopathological findings of the thymoma indicated polygonal cell type in 75 cases, mixture of polygonal and spindle cell type in 14, and spindle cell type in 3, respectively. Three cases in stage II, 12 in III, and 3 in IV a received postoperative radiation therapy. Twenty-two patients required prolonged respirator management for respiratory crisis. Complete remission of MG was seen in 15 cases (17%), and good therapeutic results were obtained in 55 cases (58%) with combined corticosteroid therapy. On the other hand, recurrences of the invasive thymoma were seen in 12 cases (13%), and six of them (6%) died of the tumor. In conclusion, early extended thymectomy including thymoma is markedly effective therapy for MG associated with thymoma, although careful attention should be paid for recurrence of the invasive thymoma.

Regulation of fusion activity by the cytoplasmic domain of a paramyxovirus F protein

SER virus is a member of the family Paramyxoviridae, genus Rubulavirus, which has been isolated from pigs. It is very closely related to SV5 virus serologically, in protein profile, and in nucleotide sequence. However, unlike SV5, SER induces minimal syncytium formation in infected CV-1 or BHK cells. Fluorescence transfer experiments between labeled erythrocytes and infected MDBK cells revealed that SER also induces hemifusion and pore formation with reduced efficiency. The virion polypeptide profiles of SER and SV5 are very similar, except that the SER F1 subunit shows an apparent molecular weight that is about 2 kDa higher than that of SV5. Comparison of the deduced amino acid sequences revealed the SER F (551 aa) to be longer than SV5 F (529 aa) by 22 residues in the cytoplasmic tail (CT) domain. The HN and M gene sequences of the viruses were found to be very similar. The SER F showed minimal fusion activity when coexpressed with either SV5 or SER HN. In contrast, SV5 F was highly fusogenic when coexpressed with either HN protein, indicating that the restricted fusion capacity of SER virus is a property of its F protein. Truncation in the CT of SER F by 22 residues completely rescued its ability to cause syncytium formation, whereas other truncations rescued syncytium formation partially. These results demonstrate that an elongated CT of a paramyxovirus F protein suppresses its membrane fusion activity.

Ambroxol suppresses influenza-virus proliferation in the mouse airway by increasing antiviral factor levels

The protective effect of ambroxol, a mucolytic agent which has antioxidant properties and stimulates the release of pulmonary surfactant, against influenza-virus proliferation in the airway was investigated in mice. Ambroxol or the vehicle was administered intraperitoneally twice a day for 5-7 days to mice shortly after intranasal infection with a lethal dose of influenza A/Aichi/68 (H3N2) virus, and the survival rate, virus titre and levels of factors regulating virus proliferation in the airway fluid were analysed. Ambroxol significantly suppressed virus multiplication and improved the survival rate of mice. The effect of ambroxol reached a peak at 10 mg x kg(-1) x day(-1), higher doses being less effective. Ambroxol stimulated the release of suppressors of influenza-virus multiplication, such as pulmonary surfactant, mucus protease inhibitor, immunoglobulin (Ig)-A and IgG, although it stimulated the release of a trypsin-type protease that potentiates virus proliferation. In addition, ambroxol transiently suppressed release of the cytokines, tumour necrosis factor-alpha, interferon-gamma and interleukin-12, into airway fluid. Although ambroxol had several negative effects on the host defence system, overall it strikingly increased the concentrations of suppressors of influenza-virus multiplication in the airway.

[Surgical treatment of aneurysm of the ductus arteriosus in the adult]

Aneurysm of the ductus arteriosus is rare, however, reports on this lesion have increased recently with the progress of thoracic aortic surgery in Japan. We report 3 male cases aged 58, 59, 73 years. Aneurysms and total aortic arch were replaced by artificial graft through median sternotomy using selective cerebral perfusion in 2 cases. Through left posterolateral thoracotomy using deep hypothermia with circulatory arrest, proximal descending thoracic aorta including the aneurysm was replaced in 1 case. Their postoperative courses were uneventful. Surgery for this lesion is safe and various surgical approaches and circulatory supporting methods can be selected depending on the size of aneurysm and associated lesions.

Mini-plasmin found in the epithelial cells of bronchioles triggers infection by broad-spectrum influenza A viruses and Sendai virus

Extracellular cleavage of virus envelope fusion glycoproteins by host cellular proteases is a prerequisite for the infectivity of mammalian and nonpathogenic avian influenza viruses, and Sendai virus. Here we report a protease present in the airway that, like tryptase Clara, can process influenza A virus haemagglutinin and Sendai virus envelope fusion glycoprotein. This protease was extracted from the membrane fraction of rat lungs, purified and then identified as a mini-plasmin. Mini-plasmin was distributed predominantly in the epithelial cells of the upward divisions of bronchioles and potentiated the replication of broad-spectrum influenza A viruses and Sendai virus, even that of the plasmin-insensitive influenza A virus strain. In comparison with plasmin, its increased hydrophobicity, leading to its higher local concentrations on membranes, and decreased molecular mass may enable mini-plasmin to gain ready access to the cleavage sites of various haemagglutinins and fusion glycoproteins after expression of these viral proteins on the cell surface. These findings suggest that mini-plasmin in the airway may play a pivotal role in the spread of viruses and their pathogenicity.

[Follow-up study of myasthenia gravis: evaluation of thymectomy in 300 patients]

From June 1975 to March 1999, 300 patients of myasthenia gravis(MG) have undergone thymectomy. Among these patients, 69 cases were classified as ocular type of MG(including 15 cases with thymoma), and 231 were generalized type of MG(including 86 cases with thymoma). The efficacy of the treatment was investigated by evaluating current patients' life activity, which is classified in 6 groups(Remission, Much Improved, Improved, Unchanged, Worse, and Died). Among the 214 cases without thymoma, Remission was 75, Much Improved was 56, and Improved was 55, namely 86.9% of these cases showed Improved or better. Among 86 cases with thymoma, Remission was 14, Much Improved was 21, and Improved was 32, namely 77.9% of these cases showed Improved or better. We concluded that post-operative outcome of these patients regardless of thymoma were generally satisfactory, but it was necessary to carry out long term careful follow-up.

Decreased expression of c-myc family genes in thymuses from myasthenia gravis patients

The thymus is a critical organ for the elimination of autoreactive T cells by apoptosis. We studied the expression of apoptosis-associated genes, bcl-xL, bad, caspase-3, and c-myc family genes in myasthenia gravis (MG) thymuses. We observed that the mRNA levels of myc family genes, c-myc and max, were markedly reduced in MG thymuses. These results indicate that c-myc-mediated signaling is abnormal in MG thymuses. The levels of molecules whose expressions are associated with myc, such as STAM, prothymosin-alpha, and NFkappaB, were also analyzed.

[A patient with facioscapulohumeral muscular dystrophy accompanied by myasthenia gravis]

A patient was a fifty-year-old man, who had a 35 year-history of facioscapulohumeral muscular dystrophy (FSHD). He was admitted to our hospital because of acute progressive weakness involving his lower extremities without any fluctuation in the recent 3 weeks. We clinically followed him for 30 years and he was able to do all daily activities, walked alone, drove a car and climbed stairs with a handrail. His 76-year-old mother had about 60 year-history of FSHD and could walk with support. On admission, neurological examination revealed moderate to marked muscle weakness and atrophy of the face, limb-girdle and all extremities, predominantly in the upper proximal limbs. He could hardly stand and needed a stick for walking. He had no blepharoptosis or ocular movement disturbance, and did not complain of difficulties in swallowing and chewing. CK values and other laboratory data were normal, and serum anti-Jo-1 antibody, anti-SSA/Ro antibody and anticardiolipin IgG antibody were negative. Because EMG examination revealed myopathic changes and an X-ray examination of the lumbar spine was normal. Thus, polymyositis and neurologenic disorders were ruled out. Disturbance in chewing and swallowing, that were uncommon in FSHD, appeared about a month after admission. Repetitive stimulation test revealed typical waning pattern. Edrophonium chloride injection was effective for decreased waning and the clinical symptoms. The titer of serum anti-ACh receptor antibody was 97 nmol/l, confirming the diagnosis of myasthenia gravis. Because of fluctuated dyspnea, thymectomy was done and his condition gradually relieved after administration of corticosteroid and choline esterase inhibitor. From this experience, we learned that we have to consider other neuromuscular disorders, even rare ones, if there existed unusual weakness of underlying muscular dystrophy.

Mechanism responsible for epileptogenic activity by first-generation H1-antagonists in rats

In the present study, we have demonstrated that multiple first-generation H1-antagonists caused behavioral and EEG seizures in rats. The epileptogenic property of pyrilamine was more potent than either chlorpheniramine or diphenhydramine. In contrast, the second-generation H1-antagonists, loratadine and ebastine did not induce detectable epileptogenic activity. Intraperitoneal injection of histidine inhibited the EEG seizures induced by pyrilamine, diphenhydramine or chlorpheniramine; however no antagonism was observed with physostigmine. These results clearly suggest that the epileptogenic activity of first-generation H1-antagonists is dependent upon a centrally acting histaminergic mechanism.

Expression of OX40 and OX40 ligand (gp34) in the normal and myasthenic thymus

OBJECTIVES

To examine the expression of OX40, an activated memory T-cell marker, and its ligand (OX40L), a set of molecules for T-cell-B-cell interaction, and other lymphocyte activation markers in the thymuses of myasthenia gravis (MG) and controls.

MATERIAL AND METHODS

We studied the expression of OX40, OX40L, IL-2Ralpha and HLA-DR in the thymic tissues of MG and controls using immunocytochemistry and flowcytometry.

RESULTS

In both hyperplastic thymus of MG and control thymus, OX40+ cells were scattered mainly in the medulla with much fewer OX40L+ cells being distributed in the corticomedullary junctions. IL-2Ralpha and HLA-DR were expressed in the medulla at higher frequencies as compared with OX40 in controls as well as MG. In contrast, the numbers of OX40+ cells around the germinal centers (GC) were significantly greater than those of control thymuses, and some mononuclear cells in GC were OX40L+. A considerable number of OX40+ cells were seen in the thymic tissues adjacent to thymomas. OX40+ cells were CD4+ CD8- or CD4+ CD8+ and were mostly HLA-DR-. (The coexpression of OX40 and IL-2Ralpha on activated CD4+ T cells was previously reported.)

CONCLUSION

OX40, expressed in a fraction of activated CD4+ T cells, may be upregulated in thymic tissues adjacent to GC and thymoma in MG, and OX40 may interact with OX40L in GC to enhance anti-acetylcholine receptor antibody production in MG.

Mast cell tryptase from pig lungs triggers infection by pneumotropic Sendai and influenza A viruses. Purification and characterization

A novel trypsin-type serine proteinase, which processes the precursors of the envelope fusion glycoproteins of pneumotropic Sendai and human influenza A viruses, was purified to homogeneity from pig lungs. On SDS/PAGE, the purified enzyme gave a protein band corresponding to about 32 kDa, and has an apparent molecular mass of 120 kDa, as determined by gel permeation chromatography. Immunohistochemical staining with antibodies against this enzyme revealed that the enzyme is located in pig lung mast cells. The N-terminal 44-amino-acid sequence of the enzyme exhibits about 80% identity with those of mast cell tryptases from other species. Of the inhibitors tested, di-isopropyl fluorophosphate, antipain, leupeptin, benzamidine and a few proteinaceous inhibitors, such as mucus protease inhibitor and aprotinin, inhibited this enzyme activity. Heparin stabilized the enzyme, but high-ionic-strength conditions did not, unlike for human mast cell tryptase. The purified enzyme efficiently processed the fusion glycoprotein precursor of Sendai virus and slowly processed hemagglutinin of human influenza A virus, and triggered the infectivity of Sendai virus in a dose-dependent manner, although human mast cell tryptase beta and rat mast cell tryptase (rat MCP-7) from lungs did not process these fusion glycoproteins at all. These results suggest that mast cell tryptase in pig lungs is the possible trigger of the pneumotropic virus infections.

Substitution of amino acid residue in influenza A virus hemagglutinin affects recognition of sialyl-oligosaccharides containing N-glycolylneuraminic acid

Sialic acids are essential components of cell surface receptors used by influenza viruses. To determine the molecular mechanisms of viral recognition of two major species of sialic acids, N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc), we tested the binding reactivity of nine human H3 influenza A viruses to sialylglycolipids containing type II sugar chain and different molecular species of terminal sialic acids. All human H3 viruses tested except A/Memphis/1/71 bound both Neu5Ac and Neu5Gc. Nucleotide sequence analysis suggests that amino acids at 143, 155, and 158 are linked to the viral recognition of Neu5Gc.

Plaque formation by and plaque cloning of Chlamydia trachomatis biovar trachoma

A new technique for the induction of plaque formation by Chlamydia trachomatis biovar trachoma applicable to the titration of infectivity and cloning of biovar trachoma was established. Three novel strains were cloned and confirmed to be free of glycogen inclusions. The lack of glycogen accumulation correlated with the absence of a 7.5-kb plasmid, which is highly conserved in other strains of C. trachomatis. Although the growth efficiency of these plasmid-free strains was slightly lower than that of plasmid-positive strains, possession of the plasmid and glycogen accumulation were not essential for the survival of C. trachomatis.

Elongation of the cytoplasmic tail interferes with the fusion activity of influenza virus hemagglutinin

The hemagglutinin (HA) of fowl plague virus was lengthened and shortened by site-specific mutagenesis at the cytoplasmic tail, and the effects of these modifications on HA functions were analyzed after expression from a simian virus 40 vector. Elongation of the tail by the addition of one to six histidine (His) residues did not interfere with intracellular transport, glycosylation, proteolytic cleavage, acylation, cell surface expression, and hemadsorption. However, the ability to induce syncytia at a low pH decreased dramatically depending on the number of His residues added. Partial fusion (hemifusion), assayed by fluorescence transfer from octadecylrhodamine-labeled erythrocyte membranes, was also reduced, but even with the mutant carrying six His residues, significant transfer was observed. However, when the formation of fusion pores was examined with hydrophilic fluorescent calcein, transfer from erythrocytes to HA-expressing cells was not observed with the mutant carrying six histidine residues. The addition of different amino acids to the cytoplasmic tail of HA caused an inhibitory effect similar to that caused by the addition of His. On the other hand, a mutant lacking the cytoplasmic tail was still able to fuse at a reduced level. These results demonstrate that elongation of the cytoplasmic tail interferes with the formation and enlargement of fusion pores. Thus, the length of the cytoplasmic tail plays a critical role in the fusion process.

Regulation of receptor binding affinity of influenza virus hemagglutinin by its carbohydrate moiety

The hemagglutinin (HA) of the fowl plague virus (FPV) strain of influenza A virus has two N-linked oligosaccharides attached to Asn123 and Asn149 in the vicinity of the receptor binding site. The effect of these carbohydrate side chains on the binding of HA to neuraminic acid-containing receptors has been analyzed. When the oligosaccharides were deleted by site-specific mutagenesis, HA expressed from a simian virus 40 vector showed enhanced hemadsorbing activity. Binding was so strong under these conditions that erythrocytes were no longer released by viral neuraminidase and that release was significantly reduced when neuraminidase from Vibrio cholerae was used. Similarly, when these oligosaccharides were removed selectively from purified viruses by N-glycosidase F, such virions were unable to elute from receptors, although they retained neuraminidase activity. Thus, release of FPV from cell receptors depends on the presence of the HA glycans at Asn123 and Asn149. On the other hand, receptor binding was abolished when these oligosaccharides were sialylated after expression in the absence of neuraminidase (M. Ohuchi, A. Feldmann, R. Ohuchi, and H.-D. Klenk, Virology 212:77-83, 1995). These observations indicate that the receptor affinity of FPV HA is controlled by oligosaccharides adjacent to the receptor binding site.

[Active site for fusion activity of influenza virus hemagglutinin]

A sequence of hydrophobic amino acids at the N-terminus of HA2 subunit of hemagglutinin (HA) is thought to be the active site for fusion activity, and called "fusion peptide". At neutral pH, fusion peptides are located inside the stem of HA spike. At pH 5, the heads of HA spike are dissociated and thereby fusion peptides are exposed and relocated probably at the top of newly formed long alpha-helix trimer. Fusogenic HA2 bridges two adjacent membranes by plunging fusion peptide into the target membrane. HA molecule is metastable at neutral pH. Oligosaccharides in the stem region, which are strictly conserved among various strains, maintain HA in the metastable form required for fusion activity. Cytoplasmic tail of HA also participates in fusion process. Addition of 5 amino acids at the end of cytoplasmic tail abolishes the fusion activity without affecting other biological properties of HA.

Laser printer optics with use of slant scanning of multiple beams

Simultaneous scanning of multiple beams in an array is an effective method to realize high-speed and high-resolution printers. The arrayed multiple beams can be generated by devices such as grating, Wollaston prism, fiber array, and laser diode array. In any of these devices, the focused spots in an array have a period several tens of times larger than the spot diameter. We propose a simultaneous scanning method suitable for these devices in which the arrayed multiple beams are arranged in a slant angle to the scanning direction to produce consecutive scan lines. Laser print experiments with two or four beams were carried out, and high-performance printing of a 431.8-mm print width, 23.6 dot/mm (i.e., 600 dot/in.) resolution, and of 541-mm/s speed were realized.

Oligosaccharides in the stem region maintain the influenza virus hemagglutinin in the metastable form required for fusion activity

The influenza A virus hemagglutinin (HA) has three conserved oligosaccharides located in the stem region at asparagine residues 12, 28, and 478. The biological role of these oligosaccharides has been investigated by mutational analysis of HA of fowl plague virus that was expressed from a simian virus 40 vector in the presence of ammonium chloride for protection from acid denaturation in the trans-Golgi network. Resistance to endoglycosidase H and cleavage of HA into the subunits HA1 and HA2 have been analyzed as markers for intracellular transport. Cell surface exposure has been determined by hemadsorption following neuraminidase treatment, by immunofluorescence staining, and by fluorescence-activated cell sorter analysis. When all three stem oligosaccharides were removed, transport was almost completely blocked. When two of the three stem oligosaccharides, particularly those at asparagine residues 12 and 28, were missing, HA was transported to the surface but showed extremely low fusion activity. With mutants lacking one stem oligosaccharide, fusion was reduced to a lesser extent. Removal of stem oligosaccharides resulted also in an increase in the pH optimum required for fusion. On the other hand, no reduction in fusion activity was observed when oligosaccharides in the head region of the HA spike were removed. These results indicate that the conserved oligosaccharides in the stem stabilize HA in the form susceptible to the conformational change necessary for fusion.

Phenotypic mixing with recombinant haemagglutinin of high cleavability mediates multi-cycle replication of human influenza virus in cell culture

When CV-1 cells expressing haemagglutinin (HA) of fowl plague virus A/FPV/34/Rostock(H7) (FPV) from an SV40-based recombinant vector were superinfected with the human influenza virus A/FM/1/47(H1N1)(FM1), phenotypically mixed progeny virus was observed. It contained cleaved FPV HA and uncleaved FM1 HA, was infectious without trypsin treatment and its infectivity was neutralizable by anti-FPV serum. When superinfection of H7 HA-expressing CV-1 cells was performed at a low multiplicity of infection, multi-cycle replication occurred. Control cells preinfected with an SV40-based recombinant not expressing FPV HA did not allow multi-cycle replication. Multi-cycle replication of FM1 virus was also observed when cells were preinfected with a vector expressing a highly cleavable mutant of influenza virus A/Port Chalmers/1/73(H3) HA carrying an insert of four arginine residues at the cleavage site. This was not the case when cells expressing uncleaved wild-type H3 HA were used. The results show that by phenotypic mixing with recombinant HA of high cleavability, a human influenza virus can be obtained in infectious form from cells lacking a suitable protease to activate this virus.

Neuraminidase is essential for fowl plague virus hemagglutinin to show hemagglutinating activity

When hemagglutinin (HA) of fowl plague virus (FPV) was expressed in CV-1 cells by a simian virus 40 vector, hemadsorption was barely detectable, although HA was exposed at the cell surface. However, treatment of HA-expressing cells with Vibrio cholerae neuraminidase (VCNA) resulted in extensive hemadsorption. VCNA treatment enhanced the electrophoretic mobility of the HA1 subunit of HA, indicating the removal of sialic acid. When two oligosaccharides in the vicinity of the receptor binding site of FPV HA were deleted by site-specific mutagenesis, VCNA treatment was not required for hemadsorption. Mutants which retained one of these oligosaccharides and mutants in which oligosaccharides not adjacent to the receptor binding site were deleted needed VCNA treatment to show hemadsorption. VCNA treatment also enhanced hemadsorption of vector-expressed HA of the WSN strain, which had a complex-type oligosaccharide in the vicinity of the receptor binding site, but had no effect on hemadsorption of Hong Kong type HA, which has a high-mannose type oligosaccharide adjacent to the receptor binding site. These results indicate that sialic acid on oligosaccharides near the receptor binding site interferes with hemadsorption. Thus, the neuraminidase is essential for FPV HA to show hemagglutinating activity.

[Comparison of long-term clinical results of the three models of the Björk-Shiley valve prosthesis and the Omnicarbon valve prosthesis]

A multi-institutional cooperative study, that was a comparison of long-term results of the replacement of the four models of the oblique disc valve prosthesis which had been implanted on aortic and mitral position alone or double from December 1976 to September 1992 in the eight national hospitals in Japan was performed. Seven hundred and thirty-four patients and 765 prostheses that consisted of 582 patients and 610 prostheses of the Björk-Shiley (BS) valve, including 326 patients of the Spherical disc (SP) valve (49 aortic, 259 mitral, and 18 double aortic-mitral), 103 patients of the Convexoconcave disc (CC) valve (45, 51, 7) and 153 patients of the Monostrut (MS) valve (101, 49, 3), and of 152 patients (71, 78, 3) and 155 prostheses of the Omnicarbon (OC) valve were compared with their mortality and morbidity in every valve position respectively according to the approval by STS-guideline. The MS valve and the OC valve showed 0% to 11.3% of operative mortality, 0.3%/py to 1.8%/py of valve related mortality, 85.5% +/- 5.6% to 98.4% +/- 1.6% of actuarial survival rate at 10 years, and 58.5% +/- 6.4% to 82.7% +/- 5.7% of actuarial free rate of all mortality and morbidity at 10 years in every valve position. Structural deteriorations occurred in two patients of the CC valve in the mitral position only, and its rate of all valve positions showed 0.04%/py. Significant differences were seen in actuarial survival rate at 10 years after aortic valve replacement, and in operative mortality rate, improved degree of NYHA class, structural deterioration rate and actuarial free rate of all mortality and morbidity after mitral valve replacement between the group of the MS and OC valve and the group of the SP and CC valve. Therefore the MS valve or the OC valve should be selected to implant rather than the SP valve or the CC valve, and the patient who had been implanted with the CC valve should be treated considering valve position, valve position, valve size, age and activity of the patient and the manufactured date of the prosthesis.

Cell tropism of influenza virus mediated by hemagglutinin activation at the stage of virus entry

When influenza virus A/WSN/33 (H1N1) was grown in MDBK or CV-1 cells in serum-free medium, progeny virus released from these cells contained only uncleaved hemagglutinin (HA). This virus was unable to infect CV-1 cells unless subjected to cleavage activation by trypsin, but it was infectious for MDBK cells without such treatment. Temperature shift experiments demonstrated that HA of radiolabeled input virus was cleaved within 30 min after inoculation of MDBK cells. As indicated by its resistance to trypsin cleavage, the virus was already internalized at this stage. Cleavage was not observed after inoculation of CV-1 cells. The serine-protease inhibitor leupeptin blocked virus growth when added to MDBK cells during the initial phase of the replication cycle. The inhibitor did not show this effect, when the input virus contained already cleaved HA. These results demonstrate that activation of HA of the WSN strain can occur in MDBK cells, but not in CV-1 cells, at the stage of virus entry, presumably by an endosomal protease.

Proteolytic cleavage of wild type and mutants of the F protein of human parainfluenza virus type 3 by two subtilisin-like endoproteases, furin and Kex2

The fusion (F) protein of human parainfluenza virus type 3 contains the tribasic cleavage site R-T-K-R, which was altered by site-directed mutagenesis. Wild-type F protein and various mutants were expressed by recombinant vaccinia viruses. The endogenous endoprotease present in CV-1 cells cleaves F variants containing the furin recognition motif R-X-K/R-R but not variants containing the dibasic site K-R or a single R at the cleavage site. A similar cleavage pattern was obtained when the subtilisin-like endoproteases Kex2 and furin were coexpressed with the wild type and mutants of the F protein. Peptidylchloromethylketone inhibitors mimicking basic cleavage sites prevent cleavage of the precursor Fo by the endogenous protease only when the furin-specific motif is present in the peptidyl portion. The data support the concept that furin is a cellular protease responsible for the activation of the F protein of human parainfluenza virus type 3.

Rescue of vector-expressed fowl plague virus hemagglutinin in biologically active form by acidotropic agents and coexpressed M2 protein

The hemagglutinin of the Rostock strain of fowl plague virus was expressed in CV-1 cells by a simian virus 40 vector, and its stability in the exocytotic transport process was examined by a fusion assay. A 50-fold increase in the fusion activity of the hemagglutinin was observed when expression occurred in the presence of ammonium chloride, Tris-HCl, or high doses of amantadine. When chloroquine, another acidotropic agent, was used, the hemagglutinin exposed at the cell surface had to be activated by trypsin, because intracellular cleavage was inhibited by this compound. Hemagglutinin mutants resistant to intracellular cleavage did not require acidotropic agents for full expression of fusion activity, when treated with trypsin after arrival at the cell surface. These results indicate that fowl plague virus hemagglutinin expressed by a simian virus 40 vector is denatured in the acidic milieu of the exocytotic pathway and that cleavage is a major factor responsible for the pH instability. Coexpression with the M2 protein also markedly enhanced the fusion activity of the hemagglutinin, and this effect was inhibited by low doses of amantadine. These results support the concept that M2, known to have ion channel function, protects the hemagglutinin from denaturation by raising the pH in the exocytotic transport system. The data also stress the importance of acidotropic agents or coexpressed M2 for the structural and functional integrity of vector-expressed hemagglutinin.

[Solitary fibrous tumor (SFT) of the thymic area--a case report]

A 52-year-old man was referred to our hospital with a large anterior mediastinal tumor on chest X-ray. A preoperative CT scan revealed the large tumor in front of the ascending aorta. We failed aspiration biopsies for several times because of scant tumor cells. This tumor was totally removed with a small part of the pericardium through median sternotomy after preoperative radiation therapy consisting of a total dose of 25 Gy. There was no metastasis to regional lymph nodes nor dissemination in the anterior mediastinum. The tumor was encapsulated, 9 x 12 cm in size, 270 g in weight with necrotic region induced by preoperative radiation therapy. We made the diagnosis of solitary fibrous tumor of the thymic area by pathological examination and immunohistochemical study. SFT most frequently arises in the pleura and is less frequently observed in the pericardium and peritoneum. But SFT of the mediastinum has been rarely reported in the world and this is the second case in Japan.

[Surgical treatment in the patients with ocular type myasthenia gravis associated with thymoma]

During past 16 years, 192 patients underwent surgery for myasthenia gravis including 40 patients with pure ocular symptoms in our institute. In these 40 patients, 8 were associated with thymoma. The clinical stages of the thymomas were registered into Stage I (n = 5), Stage II (n = 1), Stage III (n = 1), Stage IV (n = 1) according to the classification of Masaoka and colleagues. All patients underwent extended thymothymectomy. The patient in stage III had been well until generalized myasthenic symptoms appeared 4 years after the surgery. Since the chest X-ray film revealed the tumor shadow on the right diaphragm, removal of the tumor was performed. Although he developed myasthenic crisis postoperatively, he is well controlled medically. Other 7 patients have been doing well. We concluded that a close postoperative follow up should be performed for the patients with ocular type myasthenia gravis associated with thymoma.

Long-term follow up of ventricular endocardial pacing leads. Complications, electrical performance, and longevity of 561 right ventricular leads

Five hundred and sixty-one endocardial pacing leads implanted in the right ventricle of 502 patients between 1971 and 1990 were followed for up to 17 years regarding their complications, stimulation threshold behavior, and overall longevity. Lead tip dislodgment occurred in 16 leads (2.9%), in 14 of which dislodgement occurred within 2 months after implantation. The incidence of dislodgement was significantly smaller in tined leads than in nontined leads. Lead conductor fracture occurred in 19 leads (3.4%), in 15 of which fracture occurred within 5 years after implantation. Two particular sites of lead fracture were identified; i.e., one within the pacemaker pocket and the other at a particular point in the subclavian vein between the clavicle and the first rib. Fixation ligature in the former site and the venopuncture point for lead insertion in the latter site are thought to be related to lead fracture. Other complications included insulator break in 3 leads (0.5%), exit block in 7 leads (1.2%), and poor sensing in 2 leads (0.4%). The cumulative survival of leads was 94.1 +/- 2.7% (mean +/- 95% confidence interval) at 5 years, 86.3 +/- 6.3% at 10 years, and 74.2 +/- 14.0% at 15 years after implantation. The minimal stimulation threshold, lead impedance and R wave amplitude were all found to be stable for up to 10 years, and there were no tendencies toward higher stimulation threshold during the observation period of this study.

[Management of myasthenia gravis (MG) associated with thymoma]

From June 1975 to June 1992, we experienced 203 patients with MG. Sixty patients had associated thymoma, registering stages I (n = 31), II (n = 18), III (n = 9), and IV a (n = 2), according to the classification of Masaoka and colleagues. Fifty patients had generalized MG and 10 had ocular MG. Histopathological findings indicated round-oval, polygonal cell type in 46 patients and mixture of round-oval and spindle cell type in 11 patients and invasive thymomas had a tendency to have a predominantly epithelial type with and increased epithelial element as compared with non-invasive thymomas. An extended thymectomy including thymoma was performed in all patients. Three patients in stage II, 7 patients in stage III, and 2 patients in IV a received postoperative radiation therapy. Twenty-one patients needed prolonged respiratory care for respiratory crisis. Fifty-three patients have been doing well with the alternate-day corticosteroid therapy, however, 4 patients had an excavation of myasthenic symptoms associated with recurrence of thymoma on the pleura. In conclusion, early extended thymectomy including thymoma is markedly effective therapy for MG with thymoma and a careful attention should be paid for recurrence in the patients with invasive thymoma.

[Surgical treatment of double aortic arch: report of a case associated with frequent respiratory infections]

A seven-month-old baby with double aortic arch was reported. He was admitted to our hospital with complaint of frequent respiratory infections shortly after birth. On examination, bronchofiberscopy revealed compression of the trachea and left main bronchus from behind and angiography showed complete vascular ring, namely double aortic arch with no other cardiac anomaly. Soon after the operation, stridor disappeared at rest, but mild stridor persisted on exertion. Three months later, he was re-admitted to our hospital because of pneumonia. Therefore, close observation is required for the patients with double aortic arch, even if the operation is effective.

[Surgical treatment of myasthenia gravis associated with Graves's disease]

During past 30 years, we experienced 253 patients who underwent surgery for myasthenia gravis. Among these patients, 9 were associated with Graves' disease. No patients had thymoma. Five patients underwent thymectomy after they had become euthyroid by medical treatment, though four patients required subtotal thyroidectomy before thymectomy. One patient developed myasthenic crisis following thyroidectomy and was treated with respirator for 5 days. But thymectomy was performed without myasthenic crisis in these four patients between 25 days and 60 days after thyroidectomy. They have been doing well and no see-saw phenomenon was presented. Thymectomy is safe and effective even in the patients with Graves's disease, and we recommend to perform it after they become euthyroid by medical or surgical treatment.

[Two cases of broncholithiasis removed by bronchofiberscopy]

Two cases of broncholithiasis, removed bronchoscopically, are reported. Case 1 was a 38-year-old female who was admitted with hemoptysis. The chest tomogram showed calcification near the right middle lobe bronchus. Bronchoscopy revealed a broncholith in B4. Component analysis showed that more than 98% of this stone consisted of calcium carbonate. Case 2 was a 75-year-old male who was hospitalized because of continuous cough. The chest radiograph showed calcification and atelectasis in the right upper lobe. Bronchoscopically, right B3 was obstructed by a broncholith. After removal of the stone, the distal part of B3 was noted to be filled with pus. Analysis of the stone's composition revealed calcium phosphate (77%) and calcium carbonate (23%).

[A case report of cavernostomy for lung aspergilloma]

A 65-year-old male patient with right upper lobe aspergilloma treated surgically due to continuation of hemoptysis was reported. Cavernostomy was indicated in this patient, since he had a low respiratory function. After cavernostomy, cavitry infection with MRSA occurred and additional operation was necessary. We should gave great care to intra-cavitary infection. Loss of lung function after the operation seemed to be minimal.