Endophytic colonization and in planta nitrogen fixation by a Herbaspirillum sp. isolated from wild rice species

Nitrogen-fixing bacteria were isolated from the stems of wild and cultivated rice on a modified Rennie medium. Based on 16S ribosomal DNA (rDNA) sequences, the diazotrophic isolates were phylogenetically close to four genera: Herbaspirillum, Ideonella, Enterobacter, and Azospirillum. Phenotypic properties and signature sequences of 16S rDNA indicated that three isolates (B65, B501, and B512) belong to the Herbaspirillum genus. To examine whether Herbaspirillum sp. strain B501 isolated from wild rice, Oryza officinalis, endophytically colonizes rice plants, the gfp gene encoding green fluorescent protein (GFP) was introduced into the bacteria. Observations by fluorescence stereomicroscopy showed that the GFP-tagged bacteria colonized shoots and seeds of aseptically grown seedlings of the original wild rice after inoculation of the seeds. Conversely, for cultivated rice Oryza sativa, no GFP fluorescence was observed for shoots and only weak signals were observed for seeds. Observations by fluorescence and electron microscopy revealed that Herbaspirillum sp. strain B501 colonized mainly intercellular spaces in the leaves of wild rice. Colony counts of surface-sterilized rice seedlings inoculated with the GFP-tagged bacteria indicated significantly more bacterial populations inside the original wild rice than in cultivated rice varieties. Moreover, after bacterial inoculation, in planta nitrogen fixation in young seedlings of wild rice, O. officinalis, was detected by the acetylene reduction and (15)N(2) gas incorporation assays. Therefore, we conclude that Herbaspirillum sp. strain B501 is a diazotrophic endophyte compatible with wild rice, particularly O. officinalis.

Hematogenous metastases of pancreatic ductal carcinoma

To investigate the heterogeneity of hematogenous metastases of pancreatic ductal carcinoma, we investigated carcinomatous spread in 130 autopsy cases. Hepatic metastases occurred most frequently, in 81 cases (62%), which may be explained by the fact that all veins draining the pancreas flow into the portal system. We closely examined the 49 cases without hepatic metastases. Sixteen patients had pulmonary metastases without hepatic metastases, whereas seven had peculiar hematogenous metastases without hepatic or pulmonary metastases. Fifteen of these 23 patients had pancreatic body carcinomas. The unusual patterns of spread might be due to (a) hepatofugal portosystemic shunting induced by splenic vein obstruction, (b) retrograde lymphatic infiltration from metastatic tracheobronchial lymph nodes, or (c) aggressive characteristics of the tumors indicated by peculiar histologic features such as pleomorphic or mucoepidermoid carcinoma, etc. Sixteen patients showed only lymph node metastases and 10 had no distant metastases. Seventeen of these 26 cases had pancreatic head carcinoma. Histologically, two patients had mucinous cystadenocarcinomas, and six had adenocarcinomas producing rich mucin. The average age of the group with no distant metastases was higher.

Technegas for inhalation lung imaging

Technegas, an aerosol generator recently devised in Australia, produces aerosol particulates called 'technegas' which have characteristics of both an aerosol and a gas. The majority of the particulate is below 200 nm in size as measured by electron microscopy. Four normal subjects and 31 patients with various lung diseases were studied by imaging the lungs following inhalation of technegas. The penetration of inhaled technegas to the lung periphery was excellent; the average alveolar deposition ratio (ALDR) was 85%. Comparative studies with lung images obtained either with an ultrasonic nebulizer or jet nebulizers also confirmed better penetration of inhaled technegas to the lung periphery. There was no significant statistical difference in the ALDRs between normals and patients. Aerosol studies were comparable to perfusion counterparts, and evaluation of regional ventilatory status was greatly facilitated. Because of the large ALDR and the low airway deposition ratio (ADR), actual imaging could be done not only immediately after aerosol inhalation but also some time later without losing too much radioactivity from the lungs. One disadvantage was that technegas immediately after generation was anoxic.

New Bradyrhizobium japonicum strains that possess high copy numbers of the repeated sequence RS alpha

In a survey of DNA fingerprints of indigenous Bradyrhizobium japonicum with the species-specific repeated sequences RS alpha and RS beta, 21 isolates from three field sites showed numerous RS-specific hybridization bands. The isolates were designated highly reiterated sequence-possessing (HRS) isolates, and their DNA hybridization profiles were easily distinguished from the normal patterns. Some HRS isolates from two field sites possessed extremely high numbers of RS alpha copies, ranging from 86 to 175 (average, 128), and showed shifts and duplications of nif- and hup-specific hybridization bands. The HRS isolates exhibited slower growth than normal isolates, although no difference in symbiotic properties was detected between the HRS and normal isolates. Nucleotide sequence analysis of 16S rRNA genes showed that HRS isolates were strains of B. japonicum. There was no difference in the spectra of serological and hydrogenase groupings of normal and HRS isolates. Some HRS isolates possessed a tandem repeat RS alpha dimer that is similar to the structure of (IS30)2, which was shown to cause a burst of transpositional rearrangements in Escherichia coli. The results suggest that HRS isolates are derived from normal isolates in individual fields by genome rearrangements that may be mediated by insertion sequences such as RS alpha.

Neuroendocrine differentiation in pancreatic duct carcinoma special emphasis on duct-endocrine cell carcinoma of the pancreas

To evaluate the significance of neuroendocrine differentiation in duct carcinoma of the pancreas, we investigated 79 pancreatic carcinomas, applying histochemistry and immunohistochemistry (chromogranin A, Leu-7, synaptophysin and neuron-specific enolase (NSE), and correlated the morphologic differentiation pattern with clinicopathological characteristics. There were two types of neuroendocrine differentiation: scattered (n = 23) and diffuse (n = 3). The scattered type of pancreatic duct carcinoma contained scattered endocrine cells amounting to less than 10% of the neoplastic cells and was seen more frequently in well-differentiated carcinomas. There was no characteristic clinical feature found in the scattered type when compared with the tumors devoid of endocrine cells (n = 53). In contrast, the diffuse type showed diffuse immunostaining with NSE and synaptophysin in tumor cells and dense core granules ultrastructurally. These tumors showed a greater hypervascularity in angiography (p < 0.01) and the patients had relatively longer survival (33.3 months, p < 0.05) than unresectable cases of other histological types of pancreatic cancer. Two types of neuroendocrine differentiation (scattered and diffuse) existed in pancreatic ductal carcinoma. The diffuse type (Duct-Endocrine Cell Carcinoma of the Pancreas) showed synchronous duct and endocrine differentiation and particular clinical features.

Does a beta 2-stimulator really facilitate mucociliary transport in the human lungs in vivo? A study with procaterol

The purpose was to study whether procaterol, a beta 2-stimulator, facilitated mucociliary transport on the ciliated airways in the human lungs. From immediately after inhalation of [99mTc]albumin aerosol, radioactivity of the thorax was continuously measured anteriorly by a gamma camera with the examinee in the supine position; the data were sequentially stored in a computer in 10-s frame mode. Three puffs (30 micrograms) of procaterol were inhaled from a metered dose inhaler at 60 min in the same supine position, and measurement of radioactivity was continued for 30 min more. Spirometry was performed before and after the measurement of radioactivity. A group of 8 normal subjects and 34 patients with various lung diseases, including 6 with bronchial asthma in remission, were studied. In addition to observation of mucus transport on the large airways by radioaerosol inhalation lung cinescintigraphy, the time-activity curve from the right lung was evaluated and the quantitative parameters for evaluating mucociliary clearance were calculated for the right lung. Following inhalation of procaterol, there were neither significant acceleration in mucus transport on the large airways by cinescintigraphy nor significant changes in the slope of time-activity curves. Quantitative parameters did not show any significant changes either, although spirometry indicated significant bronchodilation. We conclude that three puffs of inhaled procaterol neither necessarily accelerate mucus transport nor facilitate mucociliary clearance in the human lung.

IS1631 occurrence in Bradyrhizobium japonicum highly reiterated sequence-possessing strains with high copy numbers of repeated sequences RSalpha and RSbeta

From Bradyrhizobium japonicum highly reiterated sequence-possessing (HRS) strains indigenous to Niigata and Tokachi in Japan with high copy numbers of the repeated sequences RSalpha and RSbeta (K. Minamisawa, T. Isawa, Y. Nakatsuka, and N. Ichikawa, Appl. Environ. Microbiol. 64:1845-1851, 1998), several insertion sequence (IS)-like elements were isolated by using the formation of DNA duplexes by denaturation and renaturation of total DNA, followed by treatment with S1 nuclease. Most of these sequences showed structural features of bacterial IS elements, terminal inverted repeats, and homology with known IS elements and transposase genes. HRS and non-HRS strains of B. japonicum differed markedly in the profiles obtained after hybridization with all the elements tested. In particular, HRS strains of B. japonicum contained many copies of IS1631, whereas non-HRS strains completely lacked this element. This association remained true even when many field isolates of B. japonicum were examined. Consequently, IS1631 occurrence was well correlated with B. japonicum HRS strains possessing high copy numbers of the repeated sequence RSalpha or RSbeta. DNA sequence analysis indicated that IS1631 is 2,712 bp long. In addition, IS1631 belongs to the IS21 family, as evidenced by its two open reading frames, which encode putative proteins homologous to IstA and IstB of IS21, and its terminal inverted repeat sequences with multiple short repeats.

Technegas versus krypton-81m gas as an inhalation agent. Comparison of pulmonary distribution at total lung capacity

Exactly how the pulmonary distribution of inhaled radioactive gas and Technegas, or ultra-small aerosol particulates, differs from each other, is still uncertain. The authors compared the distribution of inhaled Kr-81 m gas and Technegas in the lungs at total lung capacity in 13 control subjects with no clinical conditions and 13 patients with various chest diseases. In normal lungs, there was no difference in the distribution ratios in the right and left lungs between inhaled Kr-81m gas and Technegas. However, there was a significant difference in the lungs of patients with pulmonary disease. Technegas tended to deposit more in the lung bases than did Kr-81m gas. Despite these statistical differences, they were visually, or qualitatively, similar. From a practical and clinical standpoint, Technegas seems to be useful as an inhalation agent, unless quantitative analyses are required.

High-resolution electron microscopy of technegas and pertechnegas

Once inhaled, technegas remains in the lungs for a long period of time, whereas pertechnegas rapidly disappears. To investigate this difference, the morphology of technegas and of pertechnegas was investigated using high-resolution transmission electron microscopy. The technegas and pertechnegas were generated in an atmosphere of pure argon and in 3% oxygen in argon, respectively, using a commercially available technegas generator. For the technegas, the technetium crystals were observed to be covered with carbon, whereas they were found to have no carbon coating with the pertechnegas. Whether or not the technetium is coated with carbon appears to be responsible for the differences in behaviour of technegas and pertechnegas after deposition on the lung epithelium following inhalation.

A case of pulmonary hyalinizing granuloma

A case of pulmonary hyalinizing granuloma was presented. The patient was a 37-year-old male who was found to have abnormal chest roentgenograms showing multiple pulmonary nodules taken at the annual chest mass survey in October 1989. The largest nodule measured 35 mm in diameter. He was asymptomatic. No definite diagnosis was established either by brushing cytology, biopsy through bronchoscopy or percutaneous needle biopsy. No abnormalities were found in the GI tract, the urogenital system or the bone. Brain CT indicated an iso-density area surrounded by low density in the left fronto-parietal region. Two nodules of the lingula removed by open lung biopsy revealed a homogeneous cut surface. Histological diagnosis was pulmonary hyalinizing granuloma, consisting of hyalinized collagen fibers and bundles infiltrated with chronic inflammatory cells. No therapeutic effect was recognized with prednisolone. Craniotomy was performed and the brain lesion was removed. Anaplastic astrocytoma was the diagnosis. The brain lesion had no etiological correlation with pulmonary hyalinizing granuloma. Pulmonary hyalinizing granuloma itself is a rare benign disease with no specific therapy and is important in the differential diagnosis of lung diseases showing multiple pulmonary nodules.

Annular pancreas associated with carcinoma in the dorsal part of pancreas divisum

A carcinoma in the dorsal part of the pancreas divisum with an annular pancreas in the anterior part is reported. A 79-yr-old female was admitted in our hospital complaining of epigastralgia. Computed tomography (CT) and ultrasound (US) showed an irregular mass in the pancreatic body. A pancreatogram obtained through the major duodenal papilla demonstrated only the ventral pancreatic duct that encircled the duodenum. Contrast medium injected from the minor duodenal papilla showed Santorini's duct obstruction at the neck portion of the pancreas without communication with the ventral pancreatic duct. The patient died with liver metastases. Autopsy confirmed annular pancreas and a 6-cm tumor in the pancreatic body extending to the pancreatic head and pancreas divisum. Pancreatic carcinoma; histologically a moderately differentiated adenocarcinoma; originated from the dorsal part of pancreas divisum. To our knowledge this is the first report of pancreatic carcinoma associated with annular pancreas coexistent with pancreas divisum.

Effect of oral salbutamol on mucociliary clearance mechanisms in the lungs

The purpose of the study was to investigate whether or not orally administered salbutamol would affect mucociliary clearance function in the lungs. Salbutamol, 4 mg, was given orally 3 times a day for 7 days to 10 and 9 patients with various chest diseases in stable stage, respectively; the former were also currently taking other medications and the latter, none. Lung function tests, chest x-rays and radioaerosol inhalation lung cine-scintigraphy were performed before and after the administration of salbutamol. There was little qualitative or quantitative difference in mucociliary clearance function in either group before and after the administration of oral salbutamol, although it induced some increases in VC and FEV1.0 and a decrease in RV/TLC ratio in the former and some increases in FEV1.0, FEV1.0% and MMF in the latter. Oral salbutamol seems little to affect the mucociliary clearance function in the lungs.

Difference in inhaled aerosol deposition patterns in the lungs due to three different sized aerosols

Deposition patterns of inhaled aerosol in the lungs were studied in five normal subjects and 20 patients with lung disease by inhaling radioaerosols with three different particle size distributions. These aerosols were generated from BARC, UltraVent, and Mistogen-EN-142. Particle size distributions generated by these three nebulizers were 0.84, 1.04 and 1.93 microns in activity median aerodynamic diameter (AMAD) with its geometric standard deviation (sigma g) of 1.73, 1.71 and 1.52, respectively. Deposition patterns of inhaled aerosols were compared qualitatively and quantitatively by studying six different parameters: alveolar deposition ratio (ALDR), Xmax, Xmean, standard deviation (S.D.), skewness and kurtosis of the radioactive distribution in the lungs following inhalation. It has been found that aerosol deposition patterns varied with particle size. The unevenness of aerosol deposition, Xmax, Xmean and the number of 'hot spots' became more prominent with the increase in particle size, whereas values of ALDR and S.D. decreased as particle size increased. Knowing these deposition characteristics would facilitate a judicious application of aerosol inhalation to medical use.

Radioaerosol inhalation lung cine-scintigraphy: a preliminary report

"Radioaerosol inhalation lung cine-scintigraphy", a cinematographic display of the lungs following radioaerosol inhalation has been found to be extremely helpful not only to the visual assessment of mucociliary clearance in the lungs but also to the setting of regions of interest and to the interpretation and analysis of clearance curves over the regions of interest in the lungs. It is expected that this procedure offers an important means to the study of mucociliary clearance in health and disease in man.

Effect of non-filtered and filtered cigarette smoke on mucociliary clearance mechanism

Acute effect of a short-term exposure to cigarette smoke on mucociliary clearance mechanism was studied in 69 anesthetized dogs. A tracer material, 99mTc-MAA (macroaggregated albumin), was placed in the right main bronchus near the carina 2 min after completion of exposure and its migration distance on the tracheal mucosa with time was assessed by a scintillation camera, and the mean migrating velocity (MMV) was calculated. The average MMV values were 12.0 +/- 1.0 (mean +/- S.E.) mm/min in the control dogs, while the values were 11.6 +/- 1.5, 8.3 +/- 2.2, 3.3 +/- 0.8, and 4.2 +/- 2.3 mm/min in the dogs which smoked 1, 3, 5 and 8 cigarettes, indicating that there was an inverse correlationship between the number of cigarettes smoked and the MMV values. When cigarette smoke was filtered through a glass fiber filter, the average MMV values were 7.0 +/- 0.5 and 1.3 +/- 0.9 mm/min in the dogs which smoked 5 and 8 cigarettes respectively, suggesting that once the number of cigarettes amounted to eight, even cigarette smoke filtered through a glass fiber filter was as detrimental to the mucociliary clearance mechanism as the non-filtered cigarette smoke.

Intraoperative radiation therapy for pancreatic carcinoma. The choice of treatment modality

Ninety patients with carcinoma of the pancreas treated between 1976 and 1990 were reviewed retrospectively. Intraoperative radiation therapy (IORT) in combination with external beam radiation therapy (EBRT) for localized but unresectable tumors (n = 29) prolonged survival significantly more than IORT alone (n = 16) (p < 0.01); it seems EBRT enhanced or contributed to the better results obtained with IORT plus EBRT. Moreover, IORT, alone or in combination, relieved pain. Adjuvant IORT for residual tumors (n = 20) might not effectively prolong survival, because the difference in survival rate between noncurative resection plus IORT and nonresection plus IORT in combination with EBRT was not significant. Curative tumor resection of stage III disease in combination with IORT (n = 9) resulted in significantly longer survival as compared with curative tumor resection alone (n = 8) (p < 0.05). It may be advisable to administer IORT in combination with EBRT to patients with advanced pancreatic carcinoma, avoiding aggressive tumor resection, when curative tumor resection cannot be performed.

Mucociliary clearance mechanism in interstitial lung disease

To evaluate mucociliary clearance mechanisms of the lungs, 14 patients with pulmonary interstitial fibrosis and 8 with sarcoidosis were studied by lung function tests and radioaerosol inhalation lung cine-scintigraphy. Although all these patients showed interstitial densities on chest x-rays, only the patients with pulmonary interstitial fibrosis indicated restrictive and diffusion abnormalities by lung function tests and those with sarcoidosis did not show either of these functional abnormalities. Mucociliary clearance mechanisms were well maintained qualitatively and quantitatively in these patients with interstitial lung disease.

Normal values for quantitative parameters for evaluation of mucociliary clearance in lungs

Twenty-eight normal male subjects (13 nonsmokers and 15 smokers, 25 to 76 years of age) inhaled ultrasonically generated 99mTc-tagged human serum albumin aerosol (mass median diameter: 1.93 microns with geometric standard deviation of 1.52) and radioactivity from the thorax was measured continuously from anteriorly in 10 sec frame mode for 90 to 120 min to evaluate mucociliary clearance function in the lungs. Normal values for lung retention ratio (LRR), airway deposition ratio (ADR), airway retention ratio (ARR), airway clearance efficiency (ACE), alveolar deposition ratio (ALDR), and disappearance rate of radioactivity from the ciliated airways (DR) were presented. ALDR was significantly larger in nonsmokers than in smokers. LRR and ARR were significantly smaller and ACE, significantly larger in smokers at any time intervals than in nonsmokers, while ADR and DR were larger in smokers only in the initial 30 min following radioaerosol inhalation was completed. Thereafter there was little difference in ADR and DR between normal smokers and nonsmokers.