A case of a peritoneal dialysis patient with left pleuroperitoneal communication caused by a pericardial defect after coronary artery bypass surgery.

A 74-year-old woman with reduced kidney and cardiac function and a history of coronary artery bypass surgery involving the gastroepiploic artery to the right coronary artery and posterior descending artery #4 presented with dyspnea on exertion. Shortly after the induction of peritoneal dialysis (PD), an increase in the left pleural effusion was observed, and a diagnosis of left pleuroperitoneal communication was made by puncture drainage. The pleuroperitoneal communication hole was not detected under thoracoscopic observation; however, a 10 mm-sized hole in the pericardium was found, confirming leakage of ICG-loaded peritoneal dialysate fluid (PDF). CT peritoneography using PDF mixed with iodine contrast medium revealed that the gastroepiploic artery-to-right coronary artery pathway was defective on the abdominal side. We concluded that the left pleuroperitoneal communication was caused by a two-stage fistulous pathway between the abdominal and pleural cavities through the pericardial cavity after coronary artery bypass graft surgery. Although closure of the diaphragmatic hole around the gastroepiploic artery graft should have been performed to restart PD, the patient did not wish to undergo further invasive procedures. Identification of the fistulous pathway is extremely important for prompt diagnosis and treatment of pleuroperitoneal communication.

Partial replacement of d-glucose with d-allose ameliorates peritoneal injury and hyperglycaemia induced by peritoneal dialysis fluid in rats.

BACKGROUND: Peritoneal dialysis (PD) is a crucial dialysis method for treating end-stage kidney disease. However, its use is restricted due to high glucose-induced peritoneal injury and hyperglycaemia, particularly in patients with diabetes mellitus. In this study, we investigated whether partially replacing d-glucose with the rare sugar d-allose could ameliorate peritoneal injury and hyperglycaemia induced by peritoneal dialysis fluid (PDF). METHODS: Rat peritoneal mesothelial cells (RPMCs) were exposed to a medium containing d-glucose or d-glucose partially replaced with different concentrations of d-allose. Cell viability, oxidative stress and cytokine production were evaluated. Sprague-Dawley (SD) rats were administrated saline, a PDF containing 4% d-glucose (PDF-G4.0%) or a PDF containing 3.6% d-glucose and 0.4% d-allose (PDF-G3.6%/A0.4%) once a day for 4 weeks. Peritoneal injury and PD efficiency were assessed using immuno-histological staining and peritoneal equilibration test, respectively. Blood glucose levels were measured over 120 min following a single injection of saline or PDFs to 24-h fasted SD rats. RESULTS: In RPMCs, the partial replacement of d-glucose with d-allose increased cell viability and decreased oxidative stress and cytokine production compared to d-glucose alone. Despite the PDF-G3.6%/A0.4% having a lower d-glucose concentration compared to PDF-G4.0%, there were no significant changes in osmolality. When administered to SD rats, the PDF-G3.6%/A0.4% suppressed the elevation of peritoneal thickness and blood d-glucose levels induced by PDF-G4.0%, without impacting PD efficiency. CONCLUSIONS: Partial replacement of d-glucose with d-allose ameliorated peritoneal injury and hyperglycaemia induced by high concentration of d-glucose in PDF, indicating that d-allose could be a potential treatment option in PD.

The Fragile X Messenger Ribonucleoprotein 1 Participates in Axon Guidance Mediated by the Wnt/Planar Cell Polarity Pathway.

The Planar cell polarity (PCP) pathway is known to mediate the function of the Wnt proteins in growth cone guidance. Here, we show that the PCP pathway may directly influence local protein synthesis within the growth cones. We found that Fragile X Messenger Ribonucleoprotein 1 (FMRP) interacts with Fzd3. This interaction is negatively regulated by Wnt5a, which induces FMRP phosphorylation. Knocking down FMRP via electroporating shRNAs into the dorsal spinal cord lead to a randomization of anterior-posterior turning of post-crossing commissural axons, which could be rescued by a FMRP rescue construct. Using RNAscope, we found that some of the FMRP target mRNAs encoding PCP components, PRICKLE2 and Celsr2, as well as regulators of cytoskeletal dynamics and components of cytoskeleton, APC, Cfl1, Map1b, Tubb3 and Actb, are present in the commissural neuron growth cones. Our results suggest that PCP signaling may regulate growth cone guidance, at least in part, by regulating local protein synthesis in the growth cones through via an interaction between Frizzled3 and FMRP.

Efficacy of intraoperative fluorescence imaging using indocyanine green-containing gauze in identifying the appropriate dissection layer in laparoscopic intersphincteric resection: A case report.

In laparoscopic intersphincteric resection, identifying the dissection layer near the anus is often difficult. We safely proceeded with it, using indocyanine green-containing gauze on the anal side to remove the internal anal sphincter with indocyanine green fluorography.

Galectin-9 deficiency exacerbates lipopolysaccharide-induced hypothermia and kidney injury.

BACKGROUND: Galectin-9 (Gal-9) is a multifunctional lectin that moderates inflammation and organ damage. In this study, we tested whether Gal-9 has a protective role in the pathogenesis of endotoxemic acute kidney injury. METHODS: We examined the levels of Gal-9 in control mice after lipopolysaccharide (LPS) administration. We developed Gal-9 knockout (KO) mice that lack Gal-9 systemically and evaluated the role of Gal-9 in LPS-induced proinflammatory cytokines, vascular permeability, and renal injury. RESULTS: Gal-9 levels were increased in the plasma, kidney, and spleen within 4 h after LPS administration to wild-type mice. Gal-9 deficiency did not affect the LPS-induced increase in plasma tumor necrosis factor-α levels at 1 h or vascular permeability at 6 h. Lower urine volume and reduced creatinine clearance were observed in Gal-9-KO mice compared with wild-type mice after LPS administration. Gal-9-KO mice had limited improvement in urine volume after fluid resuscitation compared with wild-type mice. LPS reduced the body temperature 12 h after its administration. Hypothermia had disappeared in wild-type mice by 24 h, whereas it was sustained until 24 h in Gal-9-KO mice. Importantly, maintaining body temperature in Gal-9-KO mice improved the response of urine flow to fluid resuscitation. CONCLUSION: Deficiency in Gal-9 worsened LPS-induced hypothermia and kidney injury in mice. The accelerated hypothermia induced by Gal-9 deficiency contributed to the blunted response to fluid resuscitation.

Transplant Prognosis in Kidney Transplant Recipients with Diabetes under Mycophenolic Acid-Focused Therapeutic Drug Monitoring.

Mycophenolate mofetil is a key immunosuppressant that is metabolized into mycophenolic acid (MPA). The prognostic impact of MPA-focused therapeutic drug monitoring on allograft prognosis has not been determined in kidney transplant recipients with diabetes. In this study, we assessed the pharmacokinetics of MPA and allograft prognosis in recipients with diabetes. This study retrospectively analyzed 64 adult kidney transplant recipients. MPA blood concentration data (e.g., the time to the maximum concentration (Tmax), and the area under the concentration-time curve from 0 to 12 h (AUC0-12)) were collected at 3 weeks and 3 months after kidney transplantation. Of the 64 recipients, 15 had pre-existing diabetes. At 3 months after kidney transplantation, the Tmax of MPA was significantly longer in recipients with diabetes (mean (standard deviation): 2.8 (2.1) h) than in recipients without diabetes (1.9 (1.1) h, p = 0.02). However, the allograft estimated glomerular filtration rate and acute rejection rate, including borderline change, did not differ according to the diabetes status in patients with adjusted AUC0-12 of MPA within the target range. In conclusion, a longer Tmax of MPA was observed in recipients with diabetes; however, acceptable allograft prognosis was observed in kidney transplant recipients with diabetes and a sufficient AUC0-12 of MPA.

Time Course Changes in Urinary Angiotensinogen and Circulating N-Terminal Pro-B-Type Natriuretic Peptide in Patients Hospitalized with Acute Heart Failure.

Objective Home care is important in patients with heart failure (HF) in order to maintain their quality of life. A biomarker that can be measured noninvasively is needed to optimize the home care of patients with HF. Urinary angiotensinogen (uAGT) is an indicator of the intrarenal renin-angiotensin system activity, which may be augmented in HF. We hypothesized that uAGT might be a urinary biomarker in HF. Methods We measured uAGT by an enzyme-linked immunosorbent assay and uAGT normalized by urinary creatinine (uCr)-designated uAGT/uCr-at admission and discharge in 45 patients hospitalized for HF. Results We found that both uAGT/uCr [median (interquartile range): 65.5 (17.1-127.7) µg/g Cr at admission; 12.1 (6.0-37.0) µg/g Cr at discharge; p<0.01] and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels [5,422 (2,280-9,907) pg/mL at admission; 903 (510-1,729) pg/mL at discharge; p<0.01] significantly decreased between admission and discharge along with an improvement in patient's clinical status [New York Heart Association scores: 3 (3-4) at admission; 1 (1-1) at discharge; p<0.01]. The generalized least squares model revealed that the time course changes in uAGT/uCr also correlated with those in NT-proBNP levels between admission and readmission in five patients readmitted for HF. Conclusion The results indicated that the time course changes in uAGT/uCr correlated with those in the NT-proBNP levels in patients with HF who showed a clinical improvement. Further investigation and development of a kit for the rapid measurement of uAGT are needed to evaluate the clinical utility of uAGT as a biomarker in HF.

LRRK2 mediates axon development by regulating Frizzled3 phosphorylation and growth cone-growth cone communication.

Axon-axon interactions are essential for axon guidance during nervous system wiring. However, it is unknown whether and how the growth cones communicate with each other while sensing and responding to guidance cues. We found that the Parkinson's disease gene, leucine-rich repeat kinase 2 (LRRK2), has an unexpected role in growth cone-growth cone communication. The LRRK2 protein acts as a scaffold and induces Frizzled3 hyperphosphorylation indirectly by recruiting other kinases and also directly phosphorylates Frizzled3 on threonine 598 (T598). In LRRK1 or LRRK2 single knockout, LRRK1/2 double knockout, and LRRK2 G2019S knockin, the postcrossing spinal cord commissural axons are disorganized and showed anterior-posterior guidance errors after midline crossing. Growth cones from either LRRK2 knockout or G2019S knockin mice showed altered interactions, suggesting impaired communication. Intercellular interaction between Frizzled3 and Vangl2 is essential for planar cell polarity signaling. We show here that this interaction is regulated by phosphorylation of Frizzled3 at T598 and can be regulated by LRRK2 in a kinase activity-dependent way. In the LRRK1/2 double knockout or LRRK2 G2019S knockin, the dopaminergic axon bundle in the midbrain was significantly widened and appeared disorganized, showing aberrant posterior-directed growth. Our findings demonstrate that LRRK2 regulates growth cone-growth cone communication in axon guidance and that both loss-of-function mutation and a gain-of-function mutation (G2019S) cause axon guidance defects in development.

Regional differences of cFos immunoreactive cells in the preoptic areas in hypothalamus associated with heat and cold responses in mice.

cFos expression in the preoptic area (PO), which is thermoregulatory center increased by both heat and cold exposures; however, the regional difference is unknown yet. We aimed to determine if cFos expression in the PO was regionally different between heat and cold exposures. Mice were exposed to 27, 10, or 38°C for 90min, and body temperature (Tb) was measured. cFos-immunoreactive (cFos-IR) cells in the PO were counted by separating the PO into the ventral and dorsal parts in the rostral (bregma 0.38mm), central (-0.10mm), and caudal (-0.46mm) planes. Tb at 10°C remained unchanged; however, it increased at 38°C. Counts of cFos-IR cells in all areas were greater at 38°C than at 27°C. In the dorsal and ventral parts of the central and the dorsal part of caudal PO, counts of cFos-IR cells were greater at 10°C than at 27°C. In conclusion, the areas of increased cFos expression in the PO in the heat were different that in the cold in mice.

Sonic Hedgehog switches on Wnt/planar cell polarity signaling in commissural axon growth cones by reducing levels of Shisa2.

Commissural axons switch on responsiveness to Wnt attraction during midline crossing and turn anteriorly only after exiting the floor plate. We report here that Sonic Hedgehog (Shh)-Smoothened signaling downregulates Shisa2, which inhibits the glycosylation and cell surface presentation of Frizzled3 in rodent commissural axon growth cones. Constitutive Shisa2 expression causes randomized turning of post-crossing commissural axons along the anterior-posterior (A-P) axis. Loss of Shisa2 led to precocious anterior turning of commissural axons before or during midline crossing. Post-crossing commissural axon turning is completely randomized along the A-P axis when Wntless, which is essential for Wnt secretion, is conditionally knocked out in the floor plate. This regulatory link between Shh and planar cell polarity (PCP) signaling may also occur in other developmental processes.

Experimental Demonstration of Localized Plasmonic Structured Illumination Microscopy.

Super-resolution imaging methods such as structured illumination microscopy and others have offered various compromises between resolution, imaging speed, and biocompatibility. Here we experimentally demonstrate a physical mechanism for super-resolution that offers advantages over existing technologies. Using finely structured, resonant, and controllable near-field excitation from localized surface plasmons in a planar nanoantenna array, we achieve wide-field surface imaging with resolution down to 75 nm while maintaining reasonable speed and compatibility with biological specimens.

Evidence for opposing roles of Celsr3 and Vangl2 in glutamatergic synapse formation.

The signaling mechanisms that choreograph the assembly of the highly asymmetric pre- and postsynaptic structures are still poorly defined. Using synaptosome fractionation, immunostaining, and coimmunoprecipitation, we found that Celsr3 and Vangl2, core components of the planar cell polarity (PCP) pathway, are localized at developing glutamatergic synapses and interact with key synaptic proteins. Pyramidal neurons from the hippocampus of Celsr3 knockout mice exhibit loss of ∼50% of glutamatergic synapses, but not inhibitory synapses, in culture. Wnts are known regulators of synapse formation, and our data reveal that Wnt5a inhibits glutamatergic synapses formed via Celsr3. To avoid affecting earlier developmental processes, such as axon guidance, we conditionally knocked out Celsr3 in the hippocampus 1 week after birth. The CA1 neurons that lost Celsr3 also showed a loss of ∼50% of glutamatergic synapses in vivo without affecting the inhibitory synapses assessed by miniature excitatory postsynaptic current (mEPSC) and electron microscopy. These animals displayed deficits in hippocampus-dependent behaviors in adulthood, including spatial learning and memory and fear conditioning. In contrast to Celsr3 conditional knockouts, we found that the conditional knockout of Vangl2 in the hippocampus 1 week after birth led to a large increase in synaptic density, as evaluated by mEPSC frequency and spine density. PCP signaling is mediated by multiple core components with antagonizing functions. Our results document the opposing roles of Celsr3 and Vangl2 in glutamatergic synapse formation.

mtDNA diversity of the Zapotec in Mexico suggests a population decline long before the first contact with Europeans.

The New World is the last continent colonized by anatomically modern humans, Homo sapiens. The first migrants entered the New World from Asia through Beringia. It is suggested that there were three streams of Asian gene flow, one major and two additional minor gene flows. The first major migrants took a Pacific coastal route and began spreading to the American continent before the opening of the ice-free corridor. We investigated the diversity of full-length mitochondrial DNA genomes of the Zapotec population, residing in the Mesoamerican region, and reconstructed their demographic history using Bayesian Skyline Plots. We estimated the initial date of gene flow into the New World by Zapotec ancestors at around 17 000­19 000 years ago,which is highly concordant with previous studies. We also show a population decline after the initial expansion. This decline started 4000 years ago, long before European contact with Native Americans. This indicates that other factors including climatec hange should be considered to explain the observed demographic pattern.

Axon guidance and injury-lessons from Wnts and Wnt signaling.

Many studies in the past decade have revealed the role and mechanisms of Wnt signaling in axon guidance during development and the reinduction of Wnt signaling in adult central nervous system axons upon traumatic injury, which has profound influences on axon regeneration. With 19 Wnts and 14 known receptors (10 Frizzleds (Fzds), Ryk, Ror1/2 and PTK7), the Wnt family signaling proteins contribute significantly to the wiring specificity of the complex brain and spinal cord circuitry. Subsequent investigation into the signaling mechanisms showed that conserved cell polarity pathways mediate growth cone steering. These cell polarity pathways may unveil general principles of growth cone guidance. The reappeared Wnt signaling system after spinal cord injury limits the regrowth of both descending and ascending motor and sensory axons. Therefore, the knowledge of Wnt signaling mechanisms learned from axon development can be applied to axon repair in adulthood.

Complete mitogenome analysis of indigenous populations in Mexico: its relevance for the origin of Mesoamericans.

Mesoamerica has an important role in the expansion of Paleoamericans as the route to South America. In this study, we determined complete mitogenome sequences of 113 unrelated individuals from two indigenous populations of Mesoamerica, Mazahua and Zapotec. All newly sequenced mitogenomes could be classified into haplogroups A2, B2, C1 and D1, but one sequence in Mazahua was D4h3a, a subclade of haplogroup D4. This haplogroup has been mostly found in South America along the Pacific coast. Haplogroup X2a was not found in either population. Genetic similarity obtained using phylogenetic tree construction and principal component analysis showed that these two populations are distantly related to each other. Actually, the Mazahua and the Zapotec shared no sequences (haplotypes) in common, while each also showed a number of unique subclades. Surprisingly, Zapotec formed a cluster with indigenous populations living in an area from central Mesoamerica to Central America. By contrast, the Mazahua formed a group with indigenous populations living in external areas, including southwestern North America and South America. This intriguing genetic relationship suggests the presence of two paleo-Mesoamerican groups, invoking a scenario in which one group had expanded into South America and the other resided in Mesoamerica.

Antagonistic functions of Dishevelleds regulate Frizzled3 endocytosis via filopodia tips in Wnt-mediated growth cone guidance.

How growth cones detect small concentration differences of guidance cues for correct steering remains a long-standing puzzle. Commissural axons engage planar cell polarity (PCP) signaling components to turn anteriorly in a Wnt gradient after midline crossing. We found here that Frizzled3, a Wnt receptor, undergoes endocytosis via filopodia tips. Wnt5a increases Frizzled3 endocytosis, which correlates with filopodia elongation. We discovered an unexpected antagonism between Dishevelleds, which may function as a signal amplification mechanism in filopodia where PCP signaling is activated: Dishevelled2 blocks Dishevelled1-induced Frizzled3 hyperphosphorylation and membrane accumulation. A key component of apical-basal polarity (A-BP) signaling, aPKC, also inhibits Dishevelled1-induced Frizzled3 hyperphosphorylation. Celsr3, another PCP component, is required in commissural neurons for anterior turning. Frizzled3 hyperphosphorylation is increased in Celsr3 mutant mice, where PCP signaling is impaired, suggesting Frizzled3 hyperphosphorylation does correlate with loss of PCP signaling in vivo. Furthermore, we found that the small GTPase, Arf6, which is required for Frizzled3 endocytosis, is essential for Wnt-promoted outgrowth, highlighting the importance of Frizzled3 recycling in PCP signaling in growth cone guidance. In a Wnt5a gradient, more Frizzled3 endocytosis and activation of atypical protein kinase C was observed on the side of growth cones facing higher Wnt5a concentration, suggesting that spatially controlled Frizzled3 endocytosis is part of the key mechanism for growth cone steering.

CD20-positive and CD4/CD8-double-negative peripheral T-cell lymphoma of spleen complicated with severe disseminated intravascular coagulation and enteropathy.

A 71-year-old woman presented with massive splenomegaly. Open splenectomy was performed, and the diagnosis of peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), was made, with a characteristic immunophenotype of CD3(+), CD4(-), CD8(-), T-cell receptor (TCR)αß(+), and TCRγδ(-). After splenectomy, she suffered abrupt exacerbation of the lymphoma with disseminated intravascular coagulation and enteropathy. Although chemotherapy was started, her medical condition did not improve and she died a week later. Postmortem reevaluation of the pathological specimen confirmed her diagnosis as CD20(+) PTCL-NOS. Although it is a rare disease entity, CD20(+) T-cell lymphoma can demonstrate aggressive clinical behavior.

Vangl2 promotes Wnt/planar cell polarity-like signaling by antagonizing Dvl1-mediated feedback inhibition in growth cone guidance.

Although a growing body of evidence supports that Wnt-Frizzled signaling controls axon guidance from vertebrates to worms, whether and how this is mediated by planar cell polarity (PCP) signaling remain elusive. We show here that the core PCP components are required for Wnt5a-stimulated outgrowth and anterior-posterior guidance of commissural axons. Dishevelled1 can inhibit PCP signaling by increasing hyperphosphorylation of Frizzled3 and preventing its internalization. Vangl2 antagonizes that by reducing Frizzled3 phosphorylation and promotes its internalization. In commissural axon growth cones, Vangl2 is predominantly localized on the plasma membrane and is highly enriched on the tips of the filopodia as well as in patches of membrane where new filopodia emerge. Taken together, we propose that the antagonistic functions of Vangl2 and Dvl1 (over Frizzled3 hyperphosphorylation and endocytosis) allow sharpening of PCP signaling locally on the tips of the filopodia to sense directional cues, Wnts, eventually causing turning of growth cones.

Scaffolding function of PAK in the PDK1-Akt pathway.

Many extracellular signals stimulate phosphatidylinositol-3-kinase, which in turn activates the Rac1 GTPase, the protein kinase Akt and the Akt Thr 308 upstream kinase PDK1. Active Rac1 stimulates a number of events, including substrate phosphorylation by a subgroup of the PAK family of kinases. The combined effects of Rac1, PDK1 and Akt are crucial for cell migration, growth, survival, metabolism and tumorigenesis. Here we show that Rac1 stimulates a second, kinase-independent function of PAK1. The PAK1 kinase domain serves as a scaffold to facilitate Akt stimulation by PDK1 and to aid recruitment of Akt to the membrane. PAK differentially activates subpopulations of Akt. These findings reveal scaffolding functions of PAK that regulate the efficiency, localization and specificity of the PDK1-Akt pathway.

The PI3K-Akt pathway promotes microtubule stabilization in migrating fibroblasts.

Directed cell migration is controlled by extracellular cues such as growth factors/chemokines and extracellular matrix. In a migrating cell, a subset of microtubules becomes stabilized, and this stabilization is implicated in the establishment and maintenance of cell polarity. It is still not fully understood, however, how extracellular cues regulate the dynamics of microtubules. Here we show that the PI3K-Akt signaling pathway plays a pivotal role in growth factor regulation of microtubule stability. Treatment of NIH 3T3 fibroblasts with platelet-derived growth factor (PDGF) increases the amount of stabilized microtubules, and this increase is abrogated by the addition of a PI3K inhibitor or by expression of a dominant-negative form of Akt (DN-Akt), but not by the addition of a MEK inhibitor. Expression of an active form of Akt slightly increases the bulk amount of stabilized microtubules. Stabilization of microtubules induced in edge cells in the wounded monolayer culture is also attenuated by the PI3K inhibitor treatment or by expression of DN-Akt. Given that Akt is activated at the leading edge of a migrating cell and plays an essential role in directed cell migration, these results reveal a novel mechanism linking extracellular cues to directed cell migration, namely Akt regulation of microtubule stability.