A Case of Tuberculous Peritonitis Presenting as Small Bowel Obstruction.

The peritoneum is one of the common extrapulmonary sites of tuberculosis infection. Patients with underlying end-stage renal or liver disease are frequently complicated by tuberculous peritonitis; however, the diagnosis of the tuberculous peritonitis is difficult due to its insidious nature, well as its variability in presentation and limitation of available diagnostic tests. Once diagnosed, the preferred treatment is usually antituberculous therapy in uncomplicated cases. However, surgical treatment may also be required for complicated cases, such as small bowel obstruction or perforation. An 85-year-old woman was referred our hospital for abdominal pain with ileus. Despite medical therapy, prolonged ileus and progression to sepsis were shown, she underwent surgery to confirm the diagnosis and relief of mechanical ileus. Intraoperative peritoneal biopsy and macroscopic findings confirmed tuberculous peritonitis. Therefore, physicians should consider the possibility of tuberculous peritonitis in patients with unexplained small bowel obstruction.

Second-line bismuth-containing quadruple therapy for Helicobacter pylori eradication and impact of diabetes.

AIM: To investigate Helicobacter pylori (H. pylori) eradication rates using second-line bismuth-containing quadruple therapy and to identify predictors of eradication failure. METHODS: This study included 636 patients who failed first-line triple therapy and received 7 d of bismuth-containing quadruple therapy between January 2005 and December 2015. We retrospectively demonstrated H. pylori eradication rates with respect to the year of therapy as well as demographic and clinical factors. H. pylori eradication was confirmed by a 13C-urea breath test or a rapid urease test at least 4 wk after the completion of bismuth-based quadruple therapy: proton pump inhibitor, metronidazole, bismuth, and tetracycline. RESULTS: The overall eradication rates by intention-to-treat analysis and per-protocol analysis were 73.9% (95%CI: 70.1%-77.4%) and 94.5% (95%CI: 92.4%-96.5%), respectively. Annual eradication rates from 2005 to 2015 were 100.0%, 92.9%, 100.0%, 100.0%, 100.0%, 97.4%, 100.0%, 93.8%, 84.4%, 98.9%, and 92.5%, respectively, by per-protocol analysis. A multivariate analysis showed that diabetes mellitus (OR = 3.99, 95%CI: 1.56-10.20, P = 0.004) was associated with H. pylori eradication therapy failure. CONCLUSION: The second-line bismuth-containing quadruple therapy for H. pylori infection is still effective in Korea, and diabetes mellitus is suggested to be a risk factor for eradication failure.

Prognostic significance of the neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio in patients with stage III and IV colorectal cancer.

AIM: To evaluate the prognostic value of the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in patients with colorectal cancer (CRC). METHODS: Between April 1996 and December 2010, medical records from a total of 1868 patients with CRC were retrospectively reviewed. The values of simple inflammatory markers including NLR and PLR in predicting the long-term outcomes of these patients were evaluated using Kaplan-Meier curves and Cox regression models. RESULTS: The median follow-up duration was 46 mo (interquartile range, 22-73). The estimation of NLR and PLR was based on the time of diagnosis. In multivariate Cox regression analysis, high NLR (≥ 3.0) and high PLR (≥ 160) were independent risk factors predicting poor long-term outcomes in patients with stage III and IV CRC. However, high NLR and high PLR were not prognostic factors in patients with stage I and II CRC. CONCLUSION: In this study, we identified that high NLR (≥ 3.0) and high PLR (≥ 160) are useful prognostic factors to predict long-term outcomes in patients with stage III and IV CRC.

Functional water flow pathways and hydraulic regulation in the xylem network of Arabidopsis.

In vascular plants, the xylem network constitutes a complex microfluidic system. The relationship between vascular network architecture and functional hydraulic regulation during actual water flow remains unexplored. Here, we developed a method to visualize individual xylem vessels of the 3D xylem network of Arabidopsis thaliana, and to analyze the functional activities of these vessels using synchrotron X-ray computed tomography with hydrophilic gold nanoparticles as flow tracers. We show how the organization of the xylem network changes dynamically throughout the plant, and reveal how the elementary units of this transport system are organized to ensure both long-distance axial water transport and local lateral water transport. Xylem vessels form distinct clusters that operate as functional units, and the activity of these units, which determines water flow pathways, is modulated not only by varying the number and size of xylem vessels, but also by altering their interconnectivity and spatial arrangement. Based on these findings, we propose a regulatory model of water transport that ensures hydraulic efficiency and safety.

In vivo monitoring of intracellular chloroplast movements in intact leaves of C4 plants using two-photon microscopy.

Dynamic changes in the spatial distribution of chloroplasts are essential for optimizing photosynthetic capacity under changing light conditions. Light-induced movement of chloroplasts has been widely investigated, but most studies were conducted on isolated tissues or protoplasts. In this study, a two-photon microscopy (TPM) system was adapted to monitor the intracellular 3-dimensional (3D) movements of chloroplasts in intact leaves of plants during dark to light transitions. The TPM imaging was based on autofluorescence of chlorophyll generated by a femto-second Ti:Sapphire laser. All chloroplasts did not exhibit the same motion in response to irradiation variation. In the sub-epidermal mesophyll cells, chloroplasts generally moved away from the surface following blue light treatment, however many chloroplasts did not show any movement. Such spatial heterogeneity in chloroplast motility underlines the importance of monitoring intracellular orientation and movement of individual chloroplasts across intact leaves. Our investigation shows that the 3D imaging of chloroplasts using TPM can help to understand the changes in local photosynthetic capacity in intact leaves under changing environmental conditions.

Investigating water transport through the xylem network in vascular plants.

Our understanding of physical and physiological mechanisms depends on the development of advanced technologies and tools to prove or re-evaluate established theories, and test new hypotheses. Water flow in land plants is a fascinating phenomenon, a vital component of the water cycle, and essential for life on Earth. The cohesion-tension theory (CTT), formulated more than a century ago and based on the physical properties of water, laid the foundation for our understanding of water transport in vascular plants. Numerous experimental tools have since been developed to evaluate various aspects of the CTT, such as the existence of negative hydrostatic pressure. This review focuses on the evolution of the experimental methods used to study water transport in plants, and summarizes the different ways to investigate the diversity of the xylem network structure and sap flow dynamics in various species. As water transport is documented at different scales, from the level of single conduits to entire plants, it is critical that new results be subjected to systematic cross-validation and that findings based on different organs be integrated at the whole-plant level. We also discuss the functional trade-offs between optimizing hydraulic efficiency and maintaining the safety of the entire transport system. Furthermore, we evaluate future directions in sap flow research and highlight the importance of integrating the combined effects of various levels of hydraulic regulation.

X-ray CT and histological imaging of xylem vessels organization in Mimosa pudica.

Mimosa pudica has three distinct specialized organs, namely, pulvinus, secondary pulvinus, and pulvinule, which are respectively controlling the movements of petioles, leaflets, and pinna in response to external stimuli. Water flow is a key factor for such movements, but detailed studies on the organization of the vascular system for water transport in these organs have not been published yet. In this study, organizations of the xylem vessels and morphological features of the pulvinus, the secondary pulvinus, and the pulvinule were experimentally investigated by X-ray computed tomography and histological technique. Results showed that the xylem vessels were circularly distributed in the specialized motile organs and reorganized into distinct vascular bundles at the extremities. The number and the total cross-sectional area of the xylem vessels were increased inside the specialized motile organs. Morphological characteristics obtained in this study provided new insight to understand the functions of the vascular networks in the dynamic movements of M. pudica.

Hydraulic characteristics of water-refilling process in excised roots of Arabidopsis.

Plants have efficient water-transporting vascular networks with a self-recovery function from embolism, which causes fatal discontinuity in sap flow. However, the embolism-refilling process in xylem vessel is still unclear. The water-refilling processes in the individual xylem vessels of excised Arabidopsis roots were visualized in this study using synchrotron X-ray micro-imaging technique with high spatial resolution up to 1 µm per pixel and temporal resolution up to 24 fps. In normal continuous water-refilling process, we could observe various flow patterns affected by the morphological structures of the xylem vessels, especially when water passed through perforation plates. A simple criterion based on the variation in dynamic pressure was suggested to evaluate the contribution of individual perforation plates to the water-refilling process. Meanwhile, the water-refilling embolized sections of xylem vessels through radial pathways were also observed. Separated water columns were formed from this discontinuous water-refilling process and the water influx rates through the radial pathways were estimated to be 478 and 928 µm(3) s(-1). The dynamic behavior of the separated water columns were quantitatively analyzed from the stoppage of volume growth to the translational phase. These water-refilling processes in excised roots of Arabidopsis may shed light on understanding the water refilling in the embolism vessels of intact plants and the interconnectivity of xylem vessel networks in vascular plants.

Experimental analysis of the blood-sucking mechanism of female mosquitoes.

Pioneering studies have been conducted to reveal the functional characteristics of the two-pump system of the female mosquito. Mosquitoes are equipped with two pumping organs located in the head: the cibarial (CP) and the pharyngeal (PP) pumps. To analyze the functional relationship of these pumps during the blood-sucking process, micro-particle image velocimetry (PIV) and synchrotron X-ray micro-imaging were employed. The two pumps were found to be well coordinated with a phase shift (α) and time shift (ß) but to have distinct functions in the liquid-sucking process. The first pump (CP) starts to expand first, and then the second pump (PP) expands in advance with a time shift (ß) before the first pump (CP) begins to contract, playing a key role in improving pumping performance. The systaltic motion of the two pumps works systematically in a well-coordinated manner. In addition, the pumping performance of blood-sucking female mosquitoes is demonstrated to be superior to that of nectar-eating male mosquitoes. Intake flow rate is maximized by reducing the relaxation time of the CP and increasing the pumping frequency.

Synchrotron X-ray imaging for nondestructive monitoring of sap flow dynamics through xylem vessel elements in rice leaves.

A comprehensive understanding of the sap flow dynamics and xylem hydraulic properties is essential to unravel the functional features of water transport from roots to shoots in vascular plants. To evaluate quantitatively the safety and efficiency of this system, nondestructive methods to assess the interactions between sap ascent kinetics and xylem structure are required. In this study, synchrotron X-ray microscopy was employed to observe anatomical structures and sap flow dynamics in rice (Oryza sativa) xylem simultaneously. The phase-contrast imaging technique allowed nondestructive observation of the xylem structural characteristics and the air-water interfaces generated by dehydration-rehydration cycles in excised leaves. This X-ray microimaging method provided a unique tool to characterize the perforated end walls of vessel elements and to evaluate their influence on hydraulic resistance during the refilling of embolized vessels. The real-time monitoring of the axial and radial sap flow under various environmental conditions highlighted the important role of perforation plates. In summary, we report a new methodology to study the sap flow dynamics and xylem hydraulic properties with µm spatial and ms temporal resolution using X-ray microscopy. The experimental procedure described herein provides a useful handle to understand key sap transport phenomena in xylem.

Gold nanoparticle flow sensors designed for dynamic X-ray imaging in biofluids.

X-ray-based imaging is one of the most powerful and convenient methods in terms of versatility in applicable energy and high performance in use. Different from conventional nuclear medicine imaging, contrast agents are required in X-ray imaging especially for effectively targeted and molecularly specific functions. Here, in contrast to much reported static accumulation of the contrast agents in targeted organs, dynamic visualization in a living organism is successfully accomplished by the particle-traced X-ray imaging for the first time. Flow phenomena across perforated end walls of xylem vessels in rice are monitored by a gold nanoparticle (AuNP) (approximately 20 nm in diameter) as a flow tracing sensor working in nontransparent biofluids. AuNPs are surface-modified to control the hydrodynamic properties such as hydrodynamic size (DH), zeta-potential, and surface plasmonic properties in aqueous conditions. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray nanoscopy (XN), and X-ray microscopy (XM) are used to correlate the interparticle interactions with X-ray absorption ability. Cluster formation and X-ray contrast ability of the AuNPs are successfully modulated by controlling the interparticle interactions evaluated as flow-tracing sensors.

Regulation of tillering in sorghum: genotypic effects.

BACKGROUND AND AIMS: Genotypic variation in tillering can be caused by differences in the carbon supply-demand balance within a plant. The aim of this study was to understand and quantify the effects of genotype on tillering as a consequence of the underlying internal competition for carbohydrates. METHODS: Five sorghum hybrids, derived from inbred lines with a common genetic background and with similar phenology and plant height but contrasting tillering, were grown in five experiments. The experiments covered a wide range in radiation and temperature conditions, so that number of tillers produced varied significantly. Data on leaf area, tiller number, and biomass accumulation and partitioning were collected at regular intervals. To quantify internal plant competition for carbohydrates, a carbohydrate supply-demand index (S/D(index)) was developed and related to variation in tillering. KEY RESULTS: The appearance of main shoot leaves and tillers was highly co-ordinated across genotypes. High-tillering hybrids had a greater appearance frequency of early tiller ranks than low-tillering hybrids, and this was associated with narrower and hence smaller main shoot leaves. A generalized S/D(index) of internal plant competition accounted for most of the observed variation in maximum tiller number (N(tiller,max)) across genotypes. However, genotypic differences in the relationship between the S/D(index) and N(tiller,max) suggested that high-tillering hybrids also had a lower S/D threshold at which tillers appeared, possibly associated with hormonal effects. CONCLUSIONS: The results support the hypothesis that genotypic differences in tillering were associated with differences in plant carbon S/D balance, associated with differences in leaf size and in the threshold at which tillers grow out. The results provide avenues for phenotyping of mapping populations to identify genomic regions regulating tillering. Incorporating the results in crop growth simulation models could provide insight into the complex genotype-by-management-by-environment interactions associated with drought adaptation.

Regulation of tillering in sorghum: environmental effects.

BACKGROUND AND AIMS: Tillering has a significant effect on canopy development and, hence, on resource capture, crop growth and grain yield in sorghum. However, the physiological basis of tillering and its regulation by environmental effects are not fully understood. The objective of this study was to understand and quantify the environmental effects on tillering in sorghum using a carbohydrate supply-demand framework. METHODS: A series of five experiments with a wide range of radiation and temperature conditions was conducted and details of the tillering responses of a single representative hybrid were monitored. The concept of internal plant competition for carbohydrate was developed for analysis of these responses. KEY RESULTS: Tiller appearance was highly synchronized with main shoot leaf appearance, with a consistent hierarchy for tillering across environments. The main environmental effect was on the frequency of tiller appearance, in particular of the lower-rank tillers. This explained some of the observed environmental differences in the onset of tillering. A generalized index of internal plant competition, which took account of plant assimilate supply and demand (S/D(index)) during the critical period for tillering, explained most of the variation in maximum tiller number observed across the five experiments. CONCLUSIONS: This result was consistent with the hypothesis that internal plant competition for assimilates regulates tillering in sorghum. Hence, the framework outlined has a predictive value that could provide the basis for dynamic simulation of tillering in crop growth models.