Usefulness of coronal reconstruction CT images for quantitative evaluation of the cross-sectional area of small pulmonary vessels

RATIONALE AND OBJECTIVES

Cross-sectional area <5 mm(2) (CSA<5) is a computed tomography (CT) metric that has been used for the evaluation of pulmonary vessel alterations and perfusion. CSA<5 is calculated from three axial slices; thus, whether CSA<5 represents the small pulmonary vessel alterations in the whole lung remains unclear. The purpose of this study was to compare the measurements of CSA<5 using three axial slices and coronal reconstructed slices in the relationship between the measured CSA<5 and pulmonary perfusion measured using lung perfusion scintigraphy.

MATERIALS AND METHODS

This study comprised 28 subjects who underwent both noncontrast CT and lung perfusion scintigraphy. The present study measured CSA<5 using both three axial CT images and coronal reconstruction images and then obtained the percentage of the CSA in right lung to that in whole lung (R/W-CSA<5). Using anteroposterior and posteroanterior projections on technetium-99m macroaggregated albumin (MAA) lung perfusion scintigraphy, we obtained right and total lung counts and calculated the percentage of the right to whole lung counts (R/W-MAA). The correlations of the R/W-CSA<5 calculated using three axial slices (R/W-CSA(A)x<5) and coronal reconstructed slices (R/W-CSA(COR)<5) with R/W-MAA were evaluated using Spearman rank correlation analysis.

RESULTS

Both R/W-CSA(Ax)<5 and R/W-CSA(COR)<5 were significantly correlated with R/W-MAA; however, the correlation coefficient with R/W-CSA(COR)<5 (ρ = 0.842, P < .0001) was greater than that with R/W-CSA(Ax)<5 (ρ = 0.631, P = .0004).

CONCLUSIONS

Coronal reconstruction images appear suitable for quantitative measurement of CSA of small pulmonary vessels.

Contralateral lower trapezius transfer for restoration of shoulder external rotation in traumatic brachial plexus palsy: a preliminary report and literature review

The importance of external rotation of the shoulder is well accepted. Patients with inadequate recovery of shoulder function after nerve transfers for a brachial plexus injury have difficulty in using their reconstructed limb. The options for secondary procedures to improve shoulder function are often limited, especially if the spinal accessory nerve has been used earlier for nerve transfer or as a donor nerve for a free functioning muscle transfer. We have used the contralateral lower trapezius transfer to the infraspinatus in three cases, to restore shoulder external rotation. All patients had significant improvement in shoulder external rotation (mean 97°; range 80°-110°) and improved disability of the arm, shoulder and hand scores. The rotation occurred mainly at the glenohumeral joint, and was independent of the donor side. All patients were greatly satisfied with the outcome. Contralateral lower trapezius transfer appears to help in overall improvement of shoulder function by stabilizing the scapula. The results have remained stable after mean follow-up of 58 months (range 12-86). No donor site deficit was seen in any patient.

Prediction of low-frequency structure-borne sound in concrete structures using the finite-difference time-domain method

Due to limitations of computers, prediction of structure-borne sound remains difficult for large-scale problems. Herein a prediction method for low-frequency structure-borne sound transmissions on concrete structures using the finite-difference time-domain scheme is proposed. The target structure is modeled as a composition of multiple plate elements to reduce the dimensions of the simulated vibration field from three-dimensional discretization by solid elements to two-dimensional discretization. This scheme reduces both the calculation time and the amount of required memory. To validate the proposed method, the vibration characteristics using the numerical results of the proposed scheme are compared to those measured for a two-level concrete structure. Comparison of the measured and simulated results suggests that the proposed method can be used to simulate real-scale structures.

Effect of single tibial artery revascularization on microcirculation in the setting of critical limb ischemia

BACKGROUND

Benefits of 2-dimensional (2D) angiosome-oriented infrapopliteal revascularization remain controversial. The aim of this retrospective study was to clarify the effect of single tibial artery revascularization on the dorsal and plantar microcirculation of critically ischemic limbs based on skin perfusion pressure (SPP).

METHODS AND RESULTS

Fifty-seven interventions that only involved either anterior tibial artery (ATA) or posterior tibial artery (PTA) revascularization were included in this study. SPP was measured on the dorsal side (theoretically ATA perfusion area) and the plantar side (theoretically PTA perfusion area) before and after the procedure. Dorsal and plantar SPP increased significantly, from 33 (IQR 23-40.5) to 52 (IQR 32.5-65) mm Hg (P<0.0001) and 31.6±16.1 to 44.8±19.2 mm Hg (P=0.001) after ATA revascularization, respectively, and from 29.3±14.0 to 42.4±19.7 mm Hg (P=0.003) and 29.3±9.8 to 43.5±15.9 mm Hg (P<0.001) after PTA revascularization, respectively. Both ATA and PTA revascularization were not associated with any significant differences in ΔSPP between the dorsal and the plantar regions of the foot. Only 64% and 58% of ATA revascularization cases showed higher post-SPP and ΔSPP on the dorsal side than on the plantar side, respectively. Also, only 47% and 40% of PTA revascularization cases showed higher post-SPP and ΔSPP on the plantar side than on the dorsal side, respectively.

CONCLUSIONS

Single tibial artery revascularization, whether of the ATA or PTA, yielded comparable improvements in microcirculation of the dorsal and plantar foot. Approximately half of the feet revascularized had a change in microcirculation that was not consistent with the 2D angiosome theory.

VP16 fusion induces the multiple-knockout phenotype of redundant transcriptional repressors partly by Med25-independent mechanisms in Arabidopsis

Biological functions of only some plant transcriptional repressors are known owing to the lack of knockout lines or unclear phenotypes because of redundancy. Here we show that strong viral activation domain VP16 fusion to the transcriptional repressor FLOWERING LOCUS C reversed its function and caused a stronger phenotype than that of the multiple-knockout line of redundant genes, suggesting the potential of this technique to identify transcription factor function that cannot be detected in a single-knockout line. Loss-of-function of transcriptional coactivator Mediator25 did not affect VP16 activity despite their in vivo interaction, suggesting the existence of other key mechanism(s) in plants.

Effect of occlusal rehabilitation on spatial memory and hippocampal neurons after long-term loss of molars in rats

Experimental loss of occlusal support caused by the extraction or grinding of molar teeth has been reported to foment the impairment of learning and memory in laboratory animals. The purpose of this study was to examine the effect of occlusal reconstruction after long-term loss of molars on spatial memory by using 8-arm radial maze and by assessing histopathological changes of neuron density in the hippocampus. Experimental dentures were inserted into the oral cavities of molarless rats to recover the occlusal support. Age-matched groups of control, molarless and denture-wearing rats were trained to perform the maze tasks. The difference of the error incidence in the maze task was evaluated between three groups. The difference of neuron density between three groups was also evaluated at the end of the maze task. Serum corticosterone levels were also measured to estimate the chronic stress, which could be caused by extraction, insertion of the experimental denture or any experimental procedure. The error incidence in the denture-wearing group was significantly higher than that of the control group, but significantly lower than that of the molarless group. Significant differences of neuron density were observed between three groups in each of the hippocampal CA1, CA3 and DG subfields. No significant difference of the serum corticosterone levels between three groups could be observed. From the results of this study, it was suggested that the recovery of occlusal support would bring amelioration of cognitive impairment concomitant with long period loss of molars in rats.

Modified osteotomy (Kanaya's procedure) for congenital proximal radioulnar synostosis with posterior dislocation of radial head

Outcomes of Kanaya's procedure for congenital proximal radioulnar synostosis varied depending on the type of radial head dislocation. In our series of 14 patients with 17 forearms who underwent Kanaya's original procedure, the postoperative total rotation arc of the forearm was unsatisfactory in cases with posterior radial head dislocation. We examined the outcomes with respect to the type of radial head dislocation and radial shaft curvature. Radial shafts with a posterior radial head dislocation had only one curve and the radii of the curve were statistically smaller than those in anterior dislocated or enlocated heads, which had two curves. As a result, we modified the osteotomy site for proximal radioulnar synostosis with posterior radial head dislocation and achieved improved forearm rotation and physiological rotation of the radial head in our latest two cases.

Vasospastic limb ischemia presenting acute and chronic limb ischemia

Vasospastic limb ischemia might have been underappreciated compared to vasospasm in other territories such as heart and brain. However, an increasing awareness of this vascular disorder can be translated to an improved patients' care. Herein, we report a case of vasospasm presenting acute and chronic limb ischemia in four extremities.

Clinical outcomes and evaluation of the quality of life of living donors for pediatric liver transplantation: a single-center analysis of 100 donors

There are few reports about the quality of life (QOL) and morbidities of pediatric living donor liver transplantation (LDLT) donors. We evaluated the potential morbidities and identified the predictive factors regarding the QOL of living donors after pediatric LDLT. This cross-sectional study was a single-center analysis of 100 donors for pediatric LDLT. The severity of morbidities was assessed with the Clavien classification, the QOL was investigated with the short form-36 (SF-36), and the decision-making process regarding donation was analyzed with questionnaires. The median follow-up period was 3.8 years (range, 2.2-6.0 years). A total of 13% of the donors developed postoperative complications of Clavien grades I (7%), II (3%), and IIIA (3%). There was no grade IV morbidity or mortality. Eighty-one donors responded to the questionnaire and SF-36. The analysis of the questionnaires revealed that the donors had difficulty in the decision-making process, and suggested that it may be necessary to administer multistep informed consent. We identified unique predictive risk factors for lower SF-36 scores in the donors, which were the time to donation (more than 4 weeks) and the predonation self-oriented perception. The donors who have risk factors require enhanced pre- and post-donation psychological care.

Impact of aortorenal morphology on renal artery stent procedures: significance of aortic tortuosity and renal artery derivation

PURPOSE

To clarify the impact of aortorenal morphology on renal artery stenting procedures.

METHODS

A retrospective study evaluated 142 consecutive renal artery stenting procedures performed for de novo atherosclerotic renal artery stenosis in 119 patients (62 men; mean age 72±9 years, range 41-93). All procedures were done via a transfemoral approach without distal protection. Aortorenal morphology was classified into 3 types based on the relationship between abdominal aortic tortuosity and renal artery derivation. Using a straight reference line centered on the most angulated point of the inner curve of the infrarenal abdominal aorta, type 1 referred to a renal artery ostium that was more than half of the aortic diameter distance from the reference line in the greater curvature and less than half in the lesser curvature. Type 2 referred to a renal artery ostium that was less than half of the aortic diameter distant from the reference line in the greater curvature and more than half in the lesser curvature. Type 3 referred to a renal artery ostium that was beyond the reference line in the greater curvature or more than one aortic diameter from the reference line in the lesser curvature. The technical success rate, procedure time, final engagement technique, shape of the guide catheter used, and any adverse events were analyzed.

RESULTS

Type 1 aortorenal morphology was observed in 91 cases, type 2 in 30, and type 3 in 21. All cases were successfully treated; there were no technical complications, in-hospital cardiovascular events, or deaths. Procedure time differed significantly (p<0.001) among the 3 types (type 1: 19.6±5.6 minutes, type 2: 23.3±6.8 minutes, and type 3: 32.3±9.6 minutes; p<0.05 for type 1 vs. 2, p<0.001 for type 2 vs. 3, and p<0.001 for type 1 vs. 3). There were also significant differences among types in terms of engagement technique and guide catheter shape.

CONCLUSION

Aortorenal morphology was significantly associated with procedure time and the selection of engagement technique and guide catheter shape.

A national survey of patients with intestinal motility disorders who are potential candidates for intestinal transplantation in Japan

Intestinal motility disorders are a major cause of intestinal failure. Severe cases such as idiopathic pseudo-obstruction represent life-threatening illnessed. Intestinal transplantation is a treatment for severe motility disorders with irreversible intestinal failure. However, the prevalence of severe motility disorders is unknown. We performed a national survey to identify patients with intestinal motility disorders who require an intestinal transplant. The national survey of 302 institutions treating intestinal motility disorders identified 147 patients treated from 2006 to 2011 at 46 institutions. The mean patient age was 12.1 years (range, 0.3-77.5). The mean age of onset was 3.0 years (range, 0.0-68.8). Diagnoses included chronic idiopathic intestinal pseudo-obstruction (n = 96), Hirschsprung disease (n = 29), megacystis microcolon intestinal hypoperistalsis syndrome (n = 18), and other (n = 6). There were 126 survivors and 21 patients who died during the last 5 years. The mortality rate was 14.3%. Eighty-five percent of patients required parenteral nutrition for more than 6 months, which was defined as irreversible intestinal failure. Among surviving patients with irreversible intestinal failure, 8 (9.4 %) developed hepatic failure with jaundice and 27 (31.8%) 2 or more central vein thromboses. In all, at least 35 patients (41%) with irreversible failure due to intestinal motility disorders may be candidates for transplantation. The prevalence of severe intestinal motility disorders was elucidated in Japan. Severe cases should be referred to transplant centers.

Impact of rewarming preservation by continuous machine perfusion: improved post-transplant recovery in pigs

BACKGROUND

Utilization of grafts from donors after cardiac death (DCD) greatly expands the organ pool. However, implementation of such a strategy requires the development of novel preservation methods to achieve recovery from changes owing to warm ischemia.

METHODS

To assess potential methods, porcine livers harvested after 60 minutes of warm ischemic time (WIT) were perfused and preserved under the following conditions: Group 1 (n = 3), 2-hour simple cold storage and 2-hour machine perfusion (MP) at 8°C; group 2 (n = 3), 2 hours at 25°C and MP at 25°C and group 3 (n = 3), 2-hour simple cold storage and gradual rewarming to 25°C by MP. The preserved liver grafts were transplanted orthotopically into recipients.

RESULTS

The aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and hyaluronic acid (HA) levels in recipient blood at 2 hours after reperfusion were significantly lower among group 3: AST, 789 ± 258.8, 1203 ± 217.0, and 421 ± 55.8 IU/L; LDH, 1417 ± 671.2, 2132 ± 483.9, and 634 ± 263.9 IU/L; and HA, 1660 ± 556.5, 1463 ± 332.3, and 575 ± 239.0 ng/mL for groups 1, 2 and 3, respectively. Histologically, necrosis and swelling of hepatocytes were less severe among group 3 than groups 1 and 2. Group 3 animals showed better vital responses and started spontaneous breathing within 2 hours after reperfusion; 1 recipient survived for >24 hours, although all animals in groups 1 and 2 died within 2 to 3 hours after reperfusion.

CONCLUSION

Rewarming by MP preservation may facilitate recovery and resuscitation of DCD liver grafts.

A modified anaerobic digestion process with chemical sludge pre-treatment and its modelling

Activated Sludge Models (ASMs) assume an unbiodegradable organic particulate fraction in the activated sludge, which is derived from the decay of active microorganisms in the sludge and/or introduced from wastewater. In this study, a seasonal change of such activated sludge constituents in a municipal wastewater treatment plant was monitored for 1.5 years. The chemical oxygen demand ratio of the unbiodegradable particulates to the sludge showed a sinusoidal pattern ranging from 40 to 65% along with the change of water temperature in the plant that affected the decay rate. The biogas production in a laboratory-scale anaerobic digestion (AD) process was also affected by the unbiodegradable fraction in the activated sludge fed. Based on the results a chemical pre-treatment using H2O2 was conducted on the digestate to convert the unbiodegradable fraction to a biodegradable one. Once the pre-treated digestate was returned to the digester, the methane conversion increased up to 80% which was about 2.4 times as much as that of the conventional AD process, whilst 96% of volatile solids in the activated sludge was digested. From the experiment, the additional route of the organic conversion processes for the inert fraction at the pre-treatment stage was modelled on the ASM platform with reasonable simulation accuracy.

Effects of curcumin supplementation on exercise-induced oxidative stress in humans

The purpose of this study was to investigate the effects of curcumin supplementation on exercise-induced oxidative stress in humans. 10 male participants, ages 26.8±2.0 years (mean±SE), completed 3 trials in a random order: (1) placebo (control), (2) single (only before exercise) and (3) double (before and immediately after exercise) curcumin supplementation trials. Each participant received oral administration of 90 mg of curcumin or the placebo 2h before exercise and immediately after exercise. Each participant walked or ran at 65% of V˙2max on a treadmill for 60min. Blood samples were collected pre-exercise, immediately after exercise and 2h after exercise. The concentrations of serum derivatives of reactive oxygen metabolites measured immediately after exercise were significantly higher than pre-exercise values in the placebo trial (308.8±12.9 U. CARR, P<0.05), but not in the single (259.9±17.1 U. CARR) or double (273.6±19.7 U. CARR) curcumin supplementation trials. Serum biological antioxidant potential concentrations measured immediately after exercise were significantly elevated in the single and double curcumin supplementation trials compared with pre-exercise values (P<0.05). These findings indicate that curcumin supplementation can attenuate exercise-induced oxidative stress by increasing blood antioxidant capacity.

Engineering the Oryza sativa cell wall with rice NAC transcription factors regulating secondary wall formation

Plant tissues that require structural rigidity synthesize a thick, strong secondary cell wall of lignin, cellulose and hemicelluloses in a complicated bridged structure. Master regulators of secondary wall synthesis were identified in dicots, and orthologs of these regulators have been identified in monocots, but regulation of secondary cell wall formation in monocots has not been extensively studied. Here we demonstrate that the rice transcription factors SECONDARY WALL NAC DOMAIN PROTEINs (SWNs) can regulate secondary wall formation in rice (Oryza sativa) and are potentially useful for engineering the monocot cell wall. The OsSWN1 promoter is highly active in sclerenchymatous cells of the leaf blade and less active in xylem cells. By contrast, the OsSWN2 promoter is highly active in xylem cells and less active in sclerenchymatous cells. OsSWN2 splicing variants encode two proteins; the shorter protein (OsSWN2S) has very low transcriptional activation ability, but the longer protein (OsSWN2L) and OsSWN1 have strong transcriptional activation ability. In rice, expression of an OsSWN2S chimeric repressor, driven by the OsSWN2 promoter, resulted in stunted growth and para-wilting (leaf rolling and browning under normal water conditions) due to impaired vascular vessels. The same OsSWN2S chimeric repressor, driven by the OsSWN1 promoter, caused a reduction of cell wall thickening in sclerenchymatous cells, a drooping leaf phenotype, reduced lignin and xylose contents and increased digestibility as forage. These data suggest that OsSWNs regulate secondary wall formation in rice and manipulation of OsSWNs may enable improvements in monocotyledonous crops for forage or biofuel applications.

Diagnostic value of nonenhanced multidetector computed tomography for ruling out acute aortic dissection in patients presenting with chest or back pain

BACKGROUND

Multidetector computed tomography (MDCT) is widely used for diagnosing acute aortic dissection (AAD). However, the diagnostic value of nonenhanced MDCT for AAD remains unknown. We evaluated the usefulness of nonenhanced 64-slice MDCT for ruling out AAD in patients presenting with chest or back pain.

METHODS

Of 107 patients with clinical suspicion of AAD who underwent MDCT, AAD was confirmed in 47 and ruled out in 60. Nonenhanced MDCT data of all patients were retrospectively assessed by 2 independent observers unaware of clinical information and contrast-enhanced MDCT data. The diagnostic performance of nonenhanced MDCT parameters to detect AAD was calculated.

RESULTS AND CONCLUSION

Among the parameters, positive intimal flap, defined as the clear presence of a high-density membrane-like structure in the aorta on serial axial images, had a sensitivity of 87%, a specificity of 100%, a positive predictive value (PPV) of 100%, and a negative predictive value (NPV) of 91%, respectively. The addition of equivocal intimal flap, defined as the ambiguous presence of a high-density membrane-like structure in the aorta on at least one axial image, increased both the sensitivity and NPV to 96%. Furthermore, the combination of intimal flap (positive+equivocal or positive alone) and high-density area in the aorta showed the highest sensitivity (98%) and NPV (98%). Combination of the nonenhanced MDCT parameters intimal flap and high-density area in the aorta provides excellent sensitivity and NPV, suggesting that nonenhanced MDCT is an effective modality for ruling out AAD in patients with chest or back pain.