Bacterial community dynamics in aerated cow manure slurry at different aeration intensities

AIMS

This study aimed to characterize microbial community dynamics in aerated cow manure slurry at different aeration intensities.

METHODS AND RESULTS

Batch aerobic treatments were set up in 5-l jar fermentor, each containing 3 l of manure slurry; the slurries were subjected to low, medium and high (50, 150 and 250 ml min(-1), respectively) aeration for 9 days. Microbial community composition was determined using terminal restriction fragment length polymorphism and a clone library targeting 16S rRNA genes. High and medium aeration accelerated organic carbon degradation in parallel with the degree of aeration intensity; however, 90% of the initial total organic carbon was retained during low-aeration treatment. During the active stages of organic carbon decomposition, clones belonging to the class Bacilli accumulated. Moreover, Bacilli accumulation occurred earlier under high aeration than under medium aeration.

CONCLUSIONS

Organic matter degradation was mainly governed by a common microbial assemblage consisting of many lineages belonging to the class Bacilli. The timing of community development differed depending on aeration intensity.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study reports on changes in several environmentally important parameters and the principal microbial assemblage during the pollution-reducing phase of cattle manure aeration treatment.

[Reconstruction of the left common carotid artery for dissective occlusion detected by intra-operative ultrasonography]

We describe a case of Stanford type A acute aortic dissection. Replacement of the ascending aorta and aortic arch was performed using an "arch 1st technique". Following the completion of replacement, hypotension of the left superficial temporal artery pressure was detected. Ultrasonography revealed dissection of the left common carotid artery (LCCA) and compressive occlusion of the true lumen. Reconstruction of the LCCA was performed in the neck. The patient did well after the operation without any neurological abnormalities.

Generation of ribbons, helicoids, and complex Scherk surfaces in laser-matter interactions

Motivated by a diversity of the shape instability phenomena in condensed-matter physics, we study the formation of elastic ribbon structures and transformation into helicoidal structures. Using the multipulse laser-matter interaction with the Co-coated surface, a one-dimensional high-density vortex-filament array has been created. Increasing the number of pulses, the oscillatory strain field causes the cascade of the shape transformations into structures of increasing topological complexity: vortex filaments into ribbons, into ribbon helicoids and tubular-ribbon helicoids, and then into short ribbon structures with the complex Scherk surface being identified. The cascade of transformations follows the scenario in which the topological complexity of the new structure increases with the number of pulses, thus, realizing configurations with more efficient energy relaxation. Above a critical number of pulses, the system is catastrophically disintegrated into small-scale wrinkled and crumpled surfaces. We show that the critical parameter for the ribbon transformations is the number of laser pulses which is equivalent to some critical oscillatory frequency.

Inverse correlation between NKG2D expression on CD8+ T cells and the frequency of CD4+CD25+ regulatory T cells in patients with esophageal cancer

Although malignant diseases are known to be associated with immune suppression, detailed mechanisms of this phenomenon are still unknown. NKG2D is an activating cell surface receptor expressed by natural killer (NK) cells and CD8+ T cells, and it has been reported that NKG2D engagement is extremely important for T cell activation. In the current study, NKG2D expression on CD8+ T cells and the frequency of CD4+ CD25+ regulatory T (Treg) cells were determined by multicolor flow cytometry to investigate one of the mechanisms responsible for immune evasion in esophageal cancer patients. NKG2D expression on CD8+ T lymphocytes in esophageal cancer patients was significantly lower than in those of normal controls. NKG2D expression in T3/T4 esophageal cancer was significantly lower than that in T1/T2 esophageal cancer. CD8+ T cells from patients with lymph node metastasis expressed significantly lower NKG2D than those without lymph node metastasis. Moreover, significantly lower NKG2D expression was observed in stage III/IV cancer in comparison with stage I/II. The frequency of CD4+CD25+ Treg cells in esophageal cancer patients was significantly higher than those in normal controls. NKG2D expression on CD8+ T cells was significantly inversely correlated with the frequency of CD4+CD25+ Treg cells in esophageal cancer patients. Our data indicates that decreased NKG2D expression on CD8+ T cells is correlated with disease severity. Decreased NKG2D expression and an increase in Treg cells may be one of the key mechanisms responsible for immune evasion in esophageal cancer.

Supercomplex wave-vortex multiscale phenomena induced in laser-matter interactions

The interaction of laser light with a metal surface yields a complex configuration of point defects, e.g., droplets and holes and vortex microfilaments. When a single filament interacts with a defect it "winds" around the defect and can form loops, and rings. Interaction of a single filament with a single defect gives rise to arc deformation bending, formation of loops and rings, while its interaction with a two-dimensional (2D) random lattice of defects gives rise to the vortex filament splitting and breaking which occur at nodal points of the Voronoi lattice. Interaction of one-dimensional (1D) vortex filament lattice with 2D lattice of defects results in the formation of knotted structures such as the Hopf links as well as 1D and 2D Hopf link crystals, knotted along the sides of the Voronoi lattice. We observed that configurations of vortex filaments are organized at three hierarchical levels of growing complexity. Every level is comprised of the elements of the lower complexity one, indicating the presence of a supercomplexity.

[Anaphylactic shock related to aprotinin induced by anti-aprotinin immunoglobulin G antibody alone; report of a case]

Anaphylactic shock related to aprotinin has been reported to be induced exclusively in the presence of IgE antibody. And the possibility of anaphylactic shock induced by anti-aprotinin IgG antibody alone was controversial. In this paper, we describe the first case of anaphylactic shock induced by aprotinin-specific IgG antibody alone. A 55-year-old man underwent surgical repair of the descending aorta with the use of aprotinin at 2 months after first aprotinin usage. Immediately after initiation of cardiopulmonary bypass with the continuous infusion of aprotinin, clinical symptoms of anaphylactic reaction were found. Postoperative drug lymphocyte stimulation test for aprotinin and aprotinin-specific IgE antibody were negative, but aprotinin-specific IgG antibody was 163 mg/l and positive.

An ex vivo evaluation of a new root canal irrigation technique with intracanal aspiration

AIM

To evaluate the effectiveness of a new root canal irrigation technique with intracanal aspiration in removing the smear layer and to assess irrigant extrusion ex vivo.

METHODOLOGY

Thirty-five instrumented canals of extracted human canine teeth that had been resected apically by removing 3 mm of the root tip were divided into one control and four experimental groups of seven teeth each. The roots were fixed in a plastic case and surrounded with normal saline agar coloured with 1% acid red. No irrigation was performed in the control teeth. Each root canal in the experimental groups was irrigated with 9 mL of 14% ethylenediaminetetraacetic acid for 3 min, and then with 6 mL of 6% sodium hypochlorite (NaOCl) for 2 min. In the intracanal aspiration technique, the irrigant was delivered from the tip of an injection needle placed 12 mm from the apical root-end and an aspiration needle that was connected to a Root ZX apex locator placed 2 and 3 mm short of the apical root-end in groups 1 and 2, respectively. In the conventional method, the tip of an injection needle used for delivery of the irrigant and as an active electrode was placed 2 and 3 mm short of the apical root-end in groups 3 and 4, respectively, the tip of the aspiration needle was placed 12 mm from the apical root-end in these groups. The readings of the Root ZX during irrigation were recorded. The cleanliness of the canal was evaluated by scoring smear layer from scanning electron microscopy (SEM) images of the canal. Extrusion of NaOCl was detected by measuring the discoloured area of the agar around the apical root-end. The data obtained were statistically analysed by one-way anova, the Kruskal-Wallis test and Friedman's test.

RESULTS

In the SEM study, the canals in groups 1-3 were significantly cleaner than those in the control and group 4 (P < 0.05). The mean Root ZX readings in groups 1-3 were approximately "0.5". The discoloured area in group 3 was significantly larger than the other groups (P < 0.05).

CONCLUSIONS

Irrigation using the intracanal aspiration technique allowed more effective removal of the smear layer than that performed by the conventional method in an apically resected canine tooth. The intracanal aspiration technique produced limited extrusion of the irrigant beyond the apical foramen.

Preoperative measurement of the intrathrombotic pressure of a thrombosed popliteal artery aneurysm for decision of surgical indication

To evaluate the risk of rupture of a 77 mm thrombosed popliteal artery aneurysm (PAA) in an 82-year-old woman, the aneurysm was percutaneously punctured and the intrathrombotic pressure (ITP) was measured preoperatively. The percentage of the mean ITP to the mean brachial artery pressure was 80%. The aneurysm was judged to have the risk of rupture, and replacement with a prosthetic graft was performed. The percentages of the mean ITP to the mean radial artery pressure and to the mean femoral artery pressure measured intraoperatively were 83% and 71%, respectively, which approximated to the percentage measured preoperatively. PAA may have the risk of rupture even though thrombosed, and preoperative measurement of the ITP might be useful to decide surgical indication.

[Arch first technique using handmade branched graft]

We created a method using handmade branched graft to do the aortic arch surgery easier and safer. We made the branched graft using 12 and 8 mm vascular graft. A 77-year-old man with Stanford type A aortic dissection was operated with this method under deep hypothermia. After aortic root manipulation, perfusion of the aortic arch was stopped and selective cerebral perfusion was established. Left subclavian artery (LSCA) was anastomosed to one of the branches. The perfusion of the LSCA was re-started via one of its branches. Respectively, left common carotid artery and brachiocephalic artery reconstruction and reperfusion were performed in a same fashion. After distal anastomosis, anastomosis between the branched graft and main graft was performed consecutively. Postoperative course was uneventful and there was no complication. The treatment of our branched graft was easier than that of ready-made 4-branched graft. We could perform the operation under clear view for its movability with minimal cerebral ischemic time.

Stent placement for severe stenosis in the deep femoral artery with the occluded superficial femoral and popliteal arteries

In both superficial and deep femoral artery involvement, where angioplasty of the former is not suitable or feasible, angioplasty of the latter seems to be the method of choice and is a less invasive and efficient treatment particularly for limb threatening ischemia, an appropriate obstruction morphology provided. The authors describe a case of a 73-year-old man, with a rest pain of the foot and intermittent cyanosis of the toe, who underwent stent placement with transluminal angioplasty for severe stenosis in the deep femoral artery with the occluded superficial femoral and popliteal artery. The patient's ankle brachial index was remarkably increased from 0.25 to 0.61, and the preoperative symptoms were improved.

Detection of the second mesiobuccal canal in mesiobuccal roots of maxillary molar teeth ex vivo

AIM

To assess the effectiveness of magnification and dentine removal (troughing) when locating the second mesiobuccal canal in mesiobuccal roots of maxillary molars.

METHODOLOGY

A total of 208 extracted human maxillary molars were examined. After crown and pulp removal, the MB1 and 2 canals in the mesiobuccal root were located in three stages that were performed by two undergraduate dental students. Stage 1: canals were located with an endodontic explorer; stage 2: additional canals in the same teeth were located under magnification with a digital microscope (VH-8000, Keyence, Japan); stage 3: additional canals in the same teeth were located by removing dentine (troughing) from the pulp chamber floor within 3 mm from MB1 canal towards the palatal canal with an Enac ultrasonic tip (ST 21, Osada, Japan). In each group, the canals were prepared with Gates Glidden burs and K-files. The distal and palatal roots were then removed, and Indian ink was injected into the canal system within the mesio-buccal root. The root surfaces were washed with 6% NaOCl, and then rendered transparent to observe canal morphology. The root canal configurations were classified into five categories following the modified Weine's classification.

RESULTS

More than one canal in the mesio-buccal root was observed in 48% of specimens. Detection rates of multiple canals were 7, 18 and 42% following stages 1, 2 and 3, respectively. There was a significant difference between the stages for detecting the MB2 canal (P < 0.05, Friedman test).

CONCLUSIONS

Both magnification (stage 2) and dentine removal under magnification (stage 3) were effective in detecting the presence of the MB2 canal. However, MB2 canals could not be detected in 13% of the teeth because of canal calcification or branching located more apically.

PCR method is essential for detecting Mycobacterium tuberculosis in oral cavity samples

Tuberculosis is a re-emerging infectious disease, and infection by Mycobacterium tuberculosis has been increasing in immunocompromised hosts, including elderly persons. M. tuberculosis-infected persons may receive dental treatment. To evaluate the risk of M. tuberculosis infection in dental clinics, we examined the detection rates of M. tuberculosis in sample of mixed saliva, dental plaque, extracted teeth, caries lesions, and denture plaque by nested polymerase chain reaction (PCR). The detection rates by PCR in samples from mixed saliva, dental plaque, caries lesions and denture plaque obtained from tuberculosis patients were 98.0%, 92.0%, 89.0%, and 100%, respectively. The detection rates by the culture method were 17.3%, 2.0%, 0%, and 0%, respectively. M. tuberculosis also was detected from the nontuberculous mycobacteria-infected group. Strains of Actinomyces naeslundii, Porphyromonas gingivalis, and Fusobacterium nucleatum inhibited the growth of clinical strains of M. tuberculosis, but strains of Streptococcus mutans, Streptococcus sanguinis, and Actinobacillus actinomycetemcomitans did not. The present study concludes that the PCR method is essential for detecting M. tuberculosis in oral samples.