Myosteatosis as a novel predictor of new-onset diabetes mellitus after kidney transplantation

OBJECTIVES

We evaluate the effect of myosteatosis on new-onset diabetes mellitus after kidney transplantation.

METHODS

Consecutive patients who had renal transplant between 2006 and 2021 were reviewed, and 219 patients were finally included. Psoas muscle index was used to evaluate sarcopenia and average total psoas density (calculated by computed tomography before surgery) for myosteatosis. We used Cox proportional regression analyses in investigation of whether skeletal muscle depletion before surgery inclusive of sarcopenia and myosteatosis is a new additional predictor of new-onset diabetes mellitus.

RESULTS

Median recipient age and body mass index were 45 years and 21.1 kg/m2 , respectively, and 123 patients (56%) were male. Preoperative impaired glucose tolerance was present in 58 patients (27%) and new-onset diabetes mellitus in 30 patients (14%), with median psoas muscle index of 6 cm2 /m2 and average total psoas density of 41 Hounsfield Unit. In multivariate analysis, significant risk factors were body mass index ≥25 kg/m2 (p < 0.01), impaired glucose tolerance (p < 0.01), and average total psoas density < 41.9 Hounsfield Unit (p = 0.03). New-onset diabetes mellitus had incidence rates of 3.7% without risk factors, 10% with a single risk factor, 33% with two, and 60% with three. Patients with new-onset diabetes mellitus were effectively stratified by the number of risk factors (p < 0.01).

CONCLUSIONS

Myosteatosis could be a new risk factor used to predict new-onset diabetes mellitus.

Small bowel volvulus with chylous ascites: a case report

Here, we report a rare case of small bowel volvulus with chylous ascites. A 93-year-old man with a medical history of angina pectoris presented to the emergency department with abdominal pain. Computed tomography revealed a whirl sign of the mesenteric vessels with the axis of the superior mesenteric artery. A diagnosis of small bowel volvulus was made, and emergency surgery was performed. Laparoscopic examination revealed chylous ascites. Due to severe intestinal edema and difficulty in manipulating the forceps, surgery was transferred to a laparotomy. The entire small bowel was twisted 360° counterclockwise, requiring manual untwisting. Examination of the intestinal tract after untwisting revealed no evidence of ischemia or necrosis. However, because a diverticulum was observed on the mesenteric side of the upper jejunum and considering the influence of secondary small bowel volvulus, partial small bowel resection was performed. The patient had a favorable postoperative course.

A model-based pharmacokinetic assessment of drug-drug interaction between tacrolimus and nirmatrelvir/ritonavir in a kidney transplant patient with COVID-19

We experienced a patient with a remarkable and prolonged increase in tacrolimus blood concentrations when nirmatrelvir/ritonavir was concomitantly used. The inhibitory intensity and duration of nirmatrelvir/ritonavir on tacrolimus pharmacokinetics were examined using a model-based analysis. A renal transplant patient taking oral tacrolimus continuously was treated with nirmatrelvir/ritonavir for 5 days. The baseline tacrolimus trough blood concentration was 4.2 ng/mL. Tacrolimus was discontinued on Day 6 after the concomitant administration of nirmatrelvir/ritonavir, and the trough concentration increased to 96.4 ng/mL on Day 7. The model-based analysis showed that tacrolimus clearance decreased to 35% and bioavailability increased by 18.7-fold after the coadministration of nirmatrelvir/ritonavir, compared with before the coadministration. Therefore, nirmatrelvir/ritonavir drastically decreased both the apparent clearance and apparent volume of distribution. Simulated tacrolimus concentrations could be best fitted to the observed concentrations when the inhibitory effects of nirmatrelvir/ritonavir were modeled to disappear over about 10 days by first-order elimination. In conclusion, nirmatrelvir/ritonavir greatly increases tacrolimus concentrations by not only reducing clearance, but also increasing bioavailability. Interactions between nirmatrelvir/ritonavir and low-bioavailability drugs which are substrates for CYP3A and P-glycoprotein, such as tacrolimus, are harmful, and concomitant use of these medicines should be avoided.

Synthesis of biphenyl-based chiral amine catalysts from dibromopyrenes and their application in enamine catalysis

Novel axially chiral biphenyl-based amine catalysts have been designed and synthesized from dibromopyrenes. These chiral amines function as effective catalysts for asymmetric reactions through enamine intermediates.

Perceptions of Psychosocial and Ethical Issues and the Psychological Characteristics of Donors in the Clinical Setting of Living Kidney Donors: A Qualitative Study

BACKGROUND

There are several psychosocial and ethical issues surrounding the decision to be a living kidney donor. The present study aimed to determine the perceptions of psychosocial and ethical issues that living kidney donors may have, and analyze their psychological characteristics.

METHODS

Face-to-face semi-structured interviews were conducted with 15 donors. Thematic analysis was then performed to categorize the thematic elements of the transcripts. All procedures were approved by the relevant review board.

RESULTS

Four main categories were identified: Awareness of family dynamics, barriers to a proper understanding, contrasting psychological effects of recipient presence in clinical practice, insufficient information explained in informed consent.

CONCLUSION

Donors felt that they took on the "role as a care giver" for the recipient and were less aware of themselves as patients. This is a new concept that has not been shown in previous studies. Donors exist within the recipient and family, and the range of their autonomy may go beyond the traditional concept of autonomy and be rooted in relational autonomy. This study suggested that medical treatment in the presence of the recipient promotes the relational autonomy of the donor.

Association of Alpha-Actinin-3 Polymorphism With Sarcopenia in Kidney Transplant Recipients

BACKGROUND

Sarcopenia is defined as the loss of skeletal muscle mass and function and is associated with increased mortality. Certain genetic polymorphisms represent risk factors used to assess the incidence of sarcopenia; however, few studies have evaluated the association between genetic polymorphisms and sarcopenia after kidney transplantation (KTx). We examined single-nucleotide polymorphisms (SNPs) in the genes involved in sarcopenia after KTx.

METHODS

Sixty-five patients who underwent KTx were enrolled in this study. We used the psoas mass index (PMI; the cross-sectional area of the bilateral psoas muscle/height) as a surrogate marker for assessing the extent of sarcopenia. We determined the PMI before KTx and 1 year after KTx, and we identified 5 SNPs in 5 genes associated with sarcopenia in the general population. Finally, the link between the changes in PMI 1 year after KTx and each SNP was examined.

RESULTS

The median PMI before KTx and 1 year after KTx was 7.4 (4.6-13.2) and 7.0 (3.6-13.6), respectively. The PMI decreased in 43 patients (66.2%). The alpha-actinin-3 rs1815739 genotype was associated with changes in PMI; the distribution of CT+TT genotypes in the PMI decrease group was significantly higher than that of the CC genotype (odds ratio, 4.23; 95% CI 0.05-0.97; P = 0.025). Moreover, the T allele frequency was significantly higher in the PMI decrease group than in the PMI increase group (odds ratio, 2.34; 95% CI 0.18-0.950; P = 0.025).

CONCLUSION

The alpha-actinin-3 rs1815739 genotype may represent a genetic risk factor for sarcopenia after KTx.

DUV coherent light emission from ultracompact microcavity wavelength conversion device

A unique design of our ultracompact microcavity wavelength conversion device exploits the simple principle that the wavelength conversion efficiency is proportional to the square of the electric field amplitude of enhanced pump light in the microcavity, and expands the range of suitable device materials to include crystals that do not exhibit birefringence or ferroelectricity. Here, as a first step toward practical applications of all-solid-state ultracompact deep-ultraviolet coherent light sources, we adopted a low-birefringence paraelectric SrB₄O₇ crystal with great potential for wavelength conversion and high transparency down to 130 nm as our device material, and demonstrated 234 nm deep-ultraviolet coherent light generation, whose wavelength band is expected to be used for on-demand disinfection tools that can irradiate the human body.

No Influence of Everolimus on Mycophenolic Acid Area Under the Concentration-Time Curve: Limited Sampling Strategy for Mycophenolic Acid in Japanese Kidney Transplant Recipients Treated With Tacrolimus, Mycophenolate Mofetil, Steroid, and Everolimus

BACKGROUND

Despite a growing need for everolimus (EVR) to reduce calcineurin inhibitor toxicity in kidney transplantation (KTx), the influence of EVR on the pharmacokinetics of mycophenolic acid (MPA), a mycophenolate mofetil (MMF) active metabolite, is obscure, and no suitable limited sampling strategy (LSS) for MPA when EVR is concomitantly present exists. We aimed to investigate the influence of EVR on MPA pharmacokinetics in KTx.

MATERIALS AND METHODS

This study complied with all principles of the Declaration of Helsinki. Twenty patients were initially administered tacrolimus, MMF, and methylprednisolone and then received EVR 4 months after KTx. Approximately 4 weeks before and after EVR administration, the estimated value of the area under the concentration-time curve for MPA from 0 to 12 hours (MPA-AUC0-12) was calculated using MPA blood concentration just before and 1, 2, 4, and 6 hours after MMF administration. We compared several MPA pharmacokinetics parameters before and after EVR addition and determined the best estimation equation for LSS of MPA-AUC0-12.

RESULTS

Although MPA-C6 per dose (MPA-C6/D) significantly decreased after EVR addition (from 3.4 [±2.2] ng/mL/g to 2.5 [±0.9] ng/mL/g), MPA-C0/D, -C1/D, -C2/D, -C4/D, and MPA-AUC0-12/D showed no significant change. MPA-AUC0-12/D did not correlate with EVR-AUC0-12/D. The best estimation equation for LSS of MPA-AUC0-12 by 2 time points was [(2.94 × C2) + (5.09 × C4) + 5.32] (R² = 0.73) and [(5.70 × C0) + (1.39 × C1) + 22.45] (R² = 0.72) before and after EVR addition, respectively.

CONCLUSIONS

EVR can be safely combined with MMF after KTx once our results have been reevaluated.

Suppression of Allograft Fibrosis by Regulation of Mammalian Target of Rapamycin-Related Protein Expression in Kidney-Transplanted Recipients Treated with Everolimus and Reduced Tacrolimus

Background

Although renoprotective effects of everolimus (EVR) in kidney transplantation (KTx) have been widely reported, its pathophysiological mechanism remains unclear.

Material/Methods

We compared changes in eGFR (ΔGFR, ml/min/1.73 m²) and the ratio of the fibrotic area in biopsy specimens (ΔFI,%) from 3 months to 3 years after KTx between the EVR+ group (EVR addition and Tac reduction early after KTx, n=32), and the EVR− group (normal Tac without EVR, n=28). We also immunohistochemically evaluated mTOR-related protein expression.

Results

ΔGFR and ΔFI in the EVR+ vs. EVR− groups were −0.27±6.8 vs. −9.8±12.8 (p<0.001) and 2.4±4.9 vs. 9.5±10.5 (p<0.001), respectively. Phosphorylated mTOR and phosphorylated 4EBP1 expression at 3 years in the EVR+ group was significantly lower than that in the EVR− group. Moreover, in the subgroup analysis comparing ΔGFR and ΔFI among groups stratified by immunosuppressive regimen and mTOR signal enhancement, the ΔFI in patients with EVR+ with decreased mTOR signal enhancement was significantly milder than that in other patients. In addition, in the multivariate analysis, EVR addition was the only independent predictor for allograft fibrosis, whereas the Tac C₀ concentration at neither 1 nor 3 years proved to be a risk factor.

Conclusions

These results suggested that EVR addition and Tac reduction may attenuate kidney allograft fibrosis, and that the suppression of mTOR signaling process may be involved in the anti-fibrotic effect of this immunosuppressive regimen. These results provide suggestions of how to utilize EVR for patients with KTx and improve graft function.

Blood coagulation status after transcatheter aortic valve implantation between the patients with vitamin k antagonist and direct oral anticoagulants

Background

Ischemic stroke after transchatheter aortic valve implantation (TAVI) was recognized. Previous study showed that the median time of a stroke was 2.0 days (IQR, 1.0–5.0) after TAVI. One of the main mechanisms for ischemic stroke after TAVI was hyper-coagulation activity associated with TAVI procedure. However, the change of coagulation status in patients with oral anticoagulant (OAC) therapy was not investigated fully.

Purpose

We investigated the difference of blood coagulation parameters between the patients with vitamin K antagonist (VKA) and those with direct oral anticoagulants (DOAC).

Methods

We enrolled 253 patients underwent transfemoral TAVI between February 2017 and March 2019 in our hospital. Of 253 patients, 71 patients (age: 85, male: 20%) took OAC therapy (VKA: 21 patients, DOAC: 50 patients). Patients who took apixaban was 32 patients, rivaroxaban was 7, edoxaban was 11. Prothrombin activation fragment 1+2 (F1+2) as a molecular marker of thrombin generation, thrombin-anti-thrombin complex (TAT) as a marker of thrombin neutralization, soluble fibrin monomer complex (SFMC) as a marker of thrombophilia and fibrin/fibrinogen degradation product (FDP) as a marker of fibrinolysis were measured before and immediately after TAVI, and on 1 and 2 day postoperatively. We also assessed ischemic stroke after TAVI between 2 groups according to BARC-2 criteria.

Results

In patients with VKA, the value of PT-INR the day before TVAI was 1.2 (1.1–1.4). The level of F1+2 in patients with VKA was significantly greater on day 0 postoperatively than those with DOAC [855 pmol/l (595–1135) vs 614 pmol/l (452–774) P=0.003]. The level of SFMC in patients with VKA was significantly greater on day 0 postoperatively than those with DOAC [37.4 μg/ml (17.3–64.5) vs. 15.7 μg/ml (8.8–27.3) P=0.002]. The level of FDP in patients with VKA was significantly greater on day 0 postoperatively than those with DOAC [VKA: 5.8 μg/ml (3.8–7.9), DOAC: 4.0 μg/ml (3.1–5.3) P=0.023]. There were no patients with ischemic stroke among 2 groups.

Conclusion

This study revealed that coagulation activity was increased after TAVI. Furthermore, the coagulation activity in patients with VKA was significantly higher than that with DOAC at especially immediately after TAVI. Careful attention should be paid to hyper-coagulation status after TAVI in patients with VKA.

Funding Acknowledgement

Type of funding source: None

P2621Clinical safety and efficacy of tolvaptan for acute phase therapy in patients with low-flow severe aortic stenosis

Background

Conventional diuretic therapy for low-flow (LF) severe aortic stenosis (SAS) often has an inadequate effect or causes hemodynamic instability. Tolvaptan is used for acute heart failure in addition to conventional diuretics in Japan, and it does not cause intravascular dehydration.

Purpose

This study aimed to retrospectively investigate the safety and efficacy of tolvaptan in the acute phase patients with SAS and compared LF-SAS with normal-flow (NF) SAS.

Methods

56 consecutive SAS patients are analyzed. The primary endpoints were adverse clinical events (death, worsening heart failure, worsening renal failure, fatal arrhythmia, cardiogenic or hypovolemic shock, and use of inotropic agents) and the volume of urine and fluid balance within 48 hours of tolvaptan administration (Figure).

Results

Among 56 patients, 16 had LF-SAS (29%), and 40 had NF-SAS (71%). Severe adverse clinical events were not observed 48 hours after tolvaptan administration. In both groups, the urine volume significantly increased after tolvaptan administration in comparison to 24 hours before tolvaptan administration (both, p<0.01). There were no changes in the urine volume during the initial 24 and 48 hours. In the LF-SAS group, tolvaptan resulted in a significant decrease in fluid balance during the initial 24 and 48 hours compared to 24 hours before tolvaptan administration (p<0.05).

Treatment and data collection protocols

Conclusion

Adding tolvaptan to conventional treatment leads to an increase in urine output and a decreased fluid balance without hemodynamic instability in patients with LF-SAS.

Acknowledgement/Funding

None

Renal Infiltration of Macrophages in Canine and Feline Chronic Kidney Disease

During the progression of chronic kidney disease (CKD), macrophage infiltration is a crucial event leading to tubulointerstitial fibrosis. In the present study, macrophages infiltrating renal tissue in dogs and cats with CKD were analysed immunohistochemically. Iba-1 was used as a pan-macrophage marker, CD204 was used as a marker of M2 macrophages and tumour necrosis factor (TNF)-α was used as a marker of M1 macrophages. Signals for Iba1 and CD204 were observed in the interstitium of all tested kidney samples. In dogs, the signals were diffusely scattered. In cats, both diffuse and focal signals were observed. Cells that were positive for Iba1 and CD204 were also observed in the tubular lumina in cats. Co-expression of Iba1 and CD204 was also observed in the infiltrating cells by immunofluorescence labelling, and these cells were negative for TNF-α. By quantitative analysis, the indices for Iba1- and CD204-positive cells were significantly correlated with the concentrations of plasma creatinine and/or urea and the extent of interstitial fibrosis in both dogs and cats. These results demonstrated that renal infiltration of M2 macrophages plays an important role in the progression of CKD in dogs and cats. The distribution pattern of the kidney-infiltrating macrophages was unique in cats and may be associated with a cat-specific renal fibrotic process.

Spontaneous differentiation of periodontal ligament stem cells into myofibroblast during ex vivo expansion

Periodontitis is characterized by the chronic inflammation and destruction of tooth-supporting tissues. Periodontal ligament stem cell (PDLSC) is the mesenchymal stem cell (MSC) population isolated from periodontal ligament, which is the key tissue for regeneration of periodontal tissues. Although transplantation of PDLSCs is proposed as novel regenerative therapy, limited information is available, regarding the characteristic change of PDLSCs during ex vivo expansion. In this study, we encountered morphological change of PDLSCs during standard cell culture and aimed to investigate the change of PDLSCs in stem cell characteristics and to search for the culture condition to maintain stem cell properties. Characteristics of PDLSCs were examined using in vitro osteoblast and adipocyte differentiation. Myofibroblast differentiation was confirmed using immunohistochemistry and collagen gel contraction assay. Replicative senescence was examined by β-gal staining. PDLSCs changed their morphology from spindle to flat and wide during ex vivo expansion. After the morphological change, PDLSCs showed several features of myofibroblast including extensive stress fiber formation, contraction activity, and myofibroblast marker expression. Upon the morphological change, osteoblastic and adipocyte differentiation capacity were reduced and expression of stem cell-related genes were decreased. β-Gal staining was not always correlated with the morphological change of PDLSCs. Moreover, exogenous addition of bFGF and PDGF-BB served to maintain spindle shape and osteoblastic differentiation potential of PDLSCs. This study demonstrates that spontaneous differentiation of PDLSCs during ex vivo expansion and may provide the important information of cell culture condition of PDLSCs for clinical use.

Association of the PCK2 Gene Polymorphism With New-onset Glucose Intolerance in Japanese Kidney Transplant Recipients

BACKGROUND

New-onset diabetes mellitus after transplantation (NODAT) is a risk factor for both cardiovascular disease and poor graft survival after kidney transplantation (KTx). In this study, we identified single-nucleotide polymorphisms (SNPs) in genes involved in glucose metabolism and examined the correlation between these SNPs and glucose intolerance after KTx.

METHODS

Thirty-eight patients with normal glucose tolerance before KTx were included in this study. Patients with plasma glucose levels of >140 mg/dL at 120 minutes on the 75-g oral glucose tolerance test at 1 year after KTx were classified as having new-onset impaired glucose tolerance (NIGT). We identified 8 SNPs in 7 genes that are involved in glucose metabolism among the patients included in this study, and compared the prevalence rate of NIGT among SNPs in each gene.

RESULTS

Of the 38 patients, 11 (28.9%) were diagnosed with NIGT. For rs4982856 in the PCK2 gene, the distribution of genotypes among the total patient population was as follows: T/T, 12 (31.6%); T/C, 22 (57.9%); and C/C, 4 (10.5%). Seven of 11 patients with NIGT had the T/T genotype of rs4982856, whereas only 5 of 27 patients with normal glucose tolerance had this genotype. The T allele frequency of the rs4982856 was significantly higher in the NIGT group than in the normal group (81.8 vs 52.8%, respectively; P = .015).

CONCLUSION

Our study indicates that the T allele of the rs4982856 SNP in the PCK2 gene may be a risk factor for glucose intolerance after KTx.

Transcranial Doppler Ultrasound Examination in Dogs with Suspected Intracranial Hypertension Caused by Neurologic Diseases

Background

Transcranial Doppler ultrasound examination (TCD) is a rapid, noninvasive technique used to evaluate cerebral blood flow and is useful for the detection of intracranial hypertension in humans. However, the clinical usefulness of TCD in diagnosing intracranial hypertension has not been demonstrated for intracranial diseases in dogs.

Objectives

To determine the association between the TCD variables and intracranial hypertension in dogs with intracranial diseases.

Animals

Fifty client‐owned dogs with neurologic signs.

Methods

Cross‐sectional study. All dogs underwent TCD of the basilar artery under isoflurane anesthesia after magnetic resonance imaging (MRI). Dogs were classified into 3 groups based on MRI findings: no structural diseases (group I), structural disease without MRI evidence of intracranial hypertension (group II), and structural disease with MRI evidence of intracranial hypertension (group III). The TCD vascular resistance variables (resistive index [RI], pulsatility index [PI], and the ratio of systolic to diastolic mean velocity [Sm/Dm]) were measured.

Results

Fifteen, 22, and 13 dogs were classified into groups I, II, and III, respectively. Dogs in group III had significantly higher Sm/Dm (median, 1.78; range, 1.44–2.58) than those in group I (median, 1.63; range, 1.43–1.75) and group II (median, 1.62; range, 1.27–2.10). No significant differences in RI and PI were identified among groups.

Conclusions and Clinical Importance

Our findings suggest that increased Sm/Dm is associated with MRI findings of suspected intracranial hypertension in dogs with intracranial diseases and that TCD could be a useful tool to help to diagnose intracranial hypertension.

Cell transfer technology for tissue engineering

We recently developed novel cell transplantation method “cell transfer technology” utilizing photolithography. Using this method, we can transfer ex vivo expanded cells onto scaffold material in desired patterns, like printing of pictures and letters on a paper. We have investigated the possibility of this novel method for cell-based therapy using several disease models. We first transferred endothelial cells in capillary-like patterns on amnion. The transplantation of the endothelial cell-transferred amnion enhanced the reperfusion in mouse ischemic limb model. The fusion of transplanted capillary with host vessel networks was also observed. The osteoblast- and periodontal ligament stem cell-transferred amnion were next transplanted in bone and periodontal defects models. After healing period, both transplantations improved the regeneration of bone and periodontal tissues, respectively. This method was further applicable to transfer of multiple cell types and the transplantation of osteoblasts and periodontal ligament stem cell-transferred amnion resulted in the improved bone regeneration compared with single cell type transplantation. These data suggested the therapeutic potential of the technology in cell-based therapies for reperfusion of ischemic limb and regeneration of bone and periodontal tissues. Cell transfer technology is applicable to wide range of regenerative medicine in the future.

Exosomes of human placenta-derived mesenchymal stem cells stimulate angiogenesis

BACKGROUND

The therapeutic potential of mesenchymal stem cells (MSCs) may be attributed partly to humoral factors such as growth factors, cytokines, and chemokines. Human term placental tissue-derived MSCs (PlaMSCs), or conditioned medium left over from cultures of these cells, have been reported to enhance angiogenesis. Recently, the exosome, which can transport a diverse suite of macromolecules, has gained attention as a novel intercellular communication tool. However, the potential role of the exosome in PlaMSC therapeutic action is not well understood. The purpose of this study was to evaluate PlaMSC-derived exosome angiogenesis promotion in vitro and in vivo.

METHODS

MSCs were isolated from human term placental tissue by enzymatic digestion. Conditioned medium was collected after 48-h incubation in serum-free medium (PlaMSC-CM). Angiogenic factors present in PlaMSC-CM were screened by a growth factor array. Exosomes were prepared by ultracentrifugation of PlaMSC-CM, and confirmed by transmission electron microscopy, dynamic light scattering, and western blot analyses. The proangiogenic activity of PlaMSC-derived exosomes (PlaMSC-exo) was assessed using an endothelial tube formation assay, a cell migration assay, and reverse transcription-PCR analysis. The in-vivo angiogenic activity of PlaMSC-exo was evaluated using a murine auricle ischemic injury model.

RESULTS

PlaMSC-CM contained both angiogenic and angiostatic factors, which enhanced endothelial tube formation. PlaMSC-exo were incorporated into endothelial cells; these exosomes stimulated both endothelial tube formation and migration, and enhanced angiogenesis-related gene expression. Laser Doppler blood flow analysis showed that PlaMSC-exo infusion also enhanced angiogenesis in an in-vivo murine auricle ischemic injury model.

CONCLUSIONS

PlaMSC-exo enhanced angiogenesis in vitro and in vivo, suggesting that exosomes play a role in the proangiogenic activity of PlaMSCs. PlaMSC-exo may be a novel therapeutic approach for treating ischemic diseases.

Hypoxia-Inducible Factor-1α Expression in Kidney Transplant Biopsy Specimens After Reperfusion Is Associated With Early Recovery of Graft Function After Cadaveric Kidney Transplantation

BACKGROUND

Ischemia/reperfusion injury during kidney transplantation (KTx) delays allograft recovery. Hypoxia-inducible factor-1α (HIF-1α) is the key regulator of the protective response to ischemia/reperfusion injury. We evaluated the impact of the HIF-1α signaling pathway on allograft recovery during cadaveric KTx.

METHODS

Between 1996 and 2015, 46 patients underwent cadaveric KTx. The expression levels of HIF-1α-related proteins, including phosphoinositide 3-kinase, phosphorylated (p)-Akt, p-mammalian target of rapamycin, p-Eukaryotic translation initiation factor 4E, p-S6 ribosomal protein, and HIF-1α, were immunohistochemically evaluated and semi-quantitatively scored in graft biopsy specimens after 1 hour of revascularization. Ten kidney biopsy specimens collected during donor nephrectomy for living KTx were used as controls. Delayed graft function (DGF) was defined as the need for dialysis within 1 week of KTx. We compared the staining scores of each protein and several clinical parameters between patients with and those without DGF.

RESULTS

Expression levels of all six proteins in specimens after revasculization were elevated compared with those in controls. Thirty-five patients had DGF. Expression levels of PI3K, p-AKT, p-mTOR, p-eIF4E, and HIF-1α were significantly higher in patients without DGF than in those with DGF. Univariate analysis identified expression levels of p-Akt, p-S6, and HIF-1α, in addition to donor type (heart beating/non-heart beating), cold ischemic time, and donor age as significant predictors of DGF. Of these, only expression levels of HIF-1α and donor type were independently associated with DGF in multivariate analysis.

CONCLUSIONS

Up-regulation of HIF-1α in allografts after reperfusion may be a predictor of early recovery after cadaveric KTx.

Conditioned Medium from Periodontal Ligament Stem Cells Enhances Periodontal Regeneration

Periodontal disease is one of the most common infectious diseases in adults and is characterized by the destruction of tooth-supporting tissues. Mesenchymal stem cells (MSCs) comprise the mesoderm-originating stem cell population, which has been studied and used for cell therapy. However, because of the lower rate of cell survival after MSC transplantation in various disease models, paracrine functions of MSCs have been receiving increased attention as a regenerative mechanism. The aim of this study was to investigate the regenerative potential of transplanted conditioned medium (CM) obtained from cultured periodontal ligament stem cells (PDLSCs), the adult stem cell population in tooth-supporting tissues, using a rat periodontal defect model. Cell-free CM was collected from PDLSCs and fibroblasts, using ultrafiltration and transplanted into surgically created periodontal defects. Protein content of CM was examined by antibody arrays. Formation of new periodontal tissues was analyzed using microcomputed tomography and histological sections. PDLSC-CM transplantation enhanced periodontal tissue regeneration in a concentration-dependent manner, whereas fibroblast-CM did not show any regenerative function. Proteomic analysis revealed that extracellular matrix proteins, enzymes, angiogenic factors, growth factors and cytokines were contained in PDLSC-CM. Furthermore, PDLSC-CM transplantation resulted in the decreased mRNA level of tumor necrosis factor-α (TNF-α) in healing periodontal tissues. In addition, we found that PDLSC-CM suppressed the mRNA level of TNF-α in the monocyte/macrophage cell line, RAW cells, stimulated with IFN-γ. Our findings suggested that PDLSC-CM enhanced periodontal regeneration by suppressing the inflammatory response through TNF-α production, and transplantation of PDLSC-CM could be a novel approach for periodontal regenerative therapy.

Neuroprotective effects of human umbilical cord-derived mesenchymal stem cells on periventricular leukomalacia-like brain injury in neonatal rats

Background

Periventricular leukomalacia (PVL) is a type of multifactorial brain injury that causes cerebral palsy in premature infants. To date, effective therapies for PVL have not been available. In this study, we examined whether mesenchymal stem cells (MSCs) possess neuroprotective property in a lipopolysaccharide (LPS)-induced neonatal rat PVL-like brain injury.

Methods

Human umbilical cord-derived MSCs (UCMSCs) were used in this study. Four-day-old rats were intraperitoneally injected with LPS (15 mg/kg) to cause the PVL-like brain injury and were treated immediately after the LPS-injection with UCMSCs, conditioned medium prepared from MSCs (UCMSC-CM) or interferon-gamma (IFN-γ)-pretreated MSC (IFN-γ-UCMSC-CM). To assess systemic reaction to LPS-infusion, IFN-γ in sera was measured by ELISA. The brain injury was evaluated by immunostaining of myelin basic protein (MBP) and caspase-3. RT-PCR was used to quantitate pro-inflammatory cytokine levels in the brain injury, and the expression of tumor necrosis factor-stimulated gene-6 (TSG-6) or indoleamine 2,3-dioxygenase (IDO) to evaluate anti-inflammatory or immunomodulatory molecules in UCMSCs, respectively. A cytokine and growth factor array was employed to investigate the cytokine secretion profiles of UCMSCs.

Results

Elevated serum IFN-γ was observed in LPS-infused rats. The expression of IL-6, tumor necrosis factor-alpha (TNF-α), IL-1ß, and monocyte chemoattractant protein-1 (MCP-1) were increased in the brain by LPS-infusion in comparison to saline-infused control. LPS-infusion increased caspase-3-positive cells and decreased MBP-positive area in neonatal rat brains. A cytokine and growth factor array demonstrated that UCMSCs secreted various cytokines and growth factors. UCMSCs significantly suppressed IL-1ß expression in the brains and reversed LPS-caused decrease in MBP-positive area. UCMSC-CM did not reverse MBP-positive area in the injured brain, while IFN-γ-UCMSC-CM significantly increased MBP-positive area compared to control (no treatment). IFN-γ-pretreatment increased TSG-6 and IDO expression in UCMSCs.

Conclusion

We demonstrated that bolus intraperitoneal infusion of LPS caused PVL-like brain injury in neonatal rats and UCMSCs infusion ameliorated dysmyelination in LPS-induced neonatal rat brain injury. Conditioned medium prepared from IFN-γ-pretreated UCMSCs significantly reversed the brain damage in comparison with UCMSC-CM, suggesting that the preconditioning of UCMSCs would improve their neuroprotective effects. The mechanisms underline the therapeutic effects of MSCs on PVL need continued investigation to develop a more effective treatment.

Localization of Toll-like Receptor (TLR) 2 and TLR4 mRNA in the Colorectal Mucosa of Miniature Dachshunds with Inflammatory Colorectal Polyps

Inflammatory colorectal polyps (ICRPs) are characterized by the formation of multiple or solitary polyps with marked neutrophil infiltration in the colorectal area, and are speculated to be a novel form of breed-specific canine idiopathic inflammatory bowel disease (IBD). In human IBD, toll-like receptor (TLR) 2 and TLR4 have been reported to be involved in the pathogenesis of the disease. The aim of this study was to evaluate the expression of TLR2 and TLR4 mRNA in the colorectal mucosa of dogs with ICRPs by in-situ hybridization using an RNAscope assay. Samples of inflamed colorectal mucosa (n = 5) and non-inflamed mucosa (n = 5) from miniature dachshunds (MDs) with ICRPs and colonic mucosa from healthy beagles (n = 5) were examined. TLR2 and TLR4 hybridization signals were localized to the colorectal epithelium, inflammatory cells and fibroblasts in the inflamed colorectal mucosa of affected dogs. The signals were significantly greater in inflamed colorectal epithelium compared with non-inflamed epithelium of MDs with ICRPs and healthy beagles (P <0.05). These results suggest that increased expression of TLR2 and TLR4 mRNA in the inflamed colorectal mucosa results from not only inflammatory cell infiltration, but also the upregulation of TLR2 and TLR4 mRNA in the colonic epithelium.

Mitochondrial respiratory chain complex IV deficiency complicated with chronic intestinal pseudo-obstruction in a neonate

A female infant born at 36 weeks gestational age with birthweight 2135 g, and who developed respiratory disorder, hyperlactacidemia and hypertrophic cardiomyopathy after birth, was admitted to hospital at 3 days of age. After admission, bilious emesis, abdominal distention, and passage disorder of the gastrointestinal tract were resistant to various drugs. Exploratory laparotomy was performed at 93 days of age, but no organic lesions were identified and normal Meissner/Auerbach nerve plexus was confirmed, which led to a clinical diagnosis of chronic intestinal pseudo-obstruction (CIPO). She was diagnosed with mitochondrial respiratory chain complex IV deficiency on histopathology of the abdominal rectus muscle and enzyme activity measurement. This is the first report of a neonate with mitochondrial respiratory chain complex deficiency with intractable CIPO. CIPO can occur in neonates with mitochondrial respiratory chain disorder, necessitating differential diagnosis from Hirschsprung disease.

Placenta Mesenchymal Stem Cell Derived Exosomes Confer Plasticity on Fibroblasts

Mesenchymal stem cell (MSC)-conditioned medium (MSC-CM) has been reported to enhance wound healing. Exosomes contain nucleic acids, proteins, and lipids, and function as an intercellular communication vehicle for mediating some paracrine effects. However, the function of MSC-derived exosomes (MSC-exo) remains elusive. In this study, we isolated human placenta MSC (PlaMSC)-derived exosomes (PlaMSC-exo) and examined their function in vitro. PlaMSCs were isolated from human term placenta using enzymatic digestion. PlaMSC-exo were prepared from the conditioned medium of PlaMSC (PlaMSC-CM) by ultracentrifugation. The expression of stemness-related genes, such as OCT4 and NANOG, in normal adult human dermal fibroblasts (NHDF) after incubation with PlaMSC-exo was measured by real-time reverse transcriptase PCR analysis (real-time PCR). The effect of PlaMSC-exo on OCT4 transcription activity was assessed using Oct4-EGFP reporter mice-derived dermal fibroblasts. The stimulating effects of PlaMSC-exo on osteoblastic and adipocyte-differentiation of NHDF were evaluated by alkaline phosphatase (ALP), and Alizarin red S- and oil red O-staining, respectively. The expression of osteoblast- and adipocyte-related genes was also assessed by real-time PCR. The treatment of NHDF with PlaMSC-exo significantly upregulated OCT4 and NANOG mRNA expression. PlaMSC-exo also enhanced OCT4 transcription. The NHDF treated with PlaMSC-exo exhibited osteoblastic and adipocyte-differentiation in osteogenic and adipogenic induction media. PlaMSC-exo increase the expression of OCT4 and NANOG mRNA in fibroblasts. As a result, PlaMSC-exo influence the differentiation competence of fibroblasts to both osteoblastic and adipocyte-differentiation. It shows a new feature of MSCs and the possibility of clinical application of MSC-exo. J. Cell. Biochem. 117: 1658-1670, 2016. © 2015 Wiley Periodicals, Inc.

Vitamin D Status in Different Stages of Disease Severity in Dogs with Chronic Valvular Heart Disease

Background

In humans with heart disease, vitamin D deficiency is associated with disease progression and a poor prognosis. A recent study showed that serum 25‐hydroxyvitamin D [25(OH)D] concentration, the hallmark of vitamin D status, was lower in dogs with heart failure than in normal dogs, and a low concentration was associated with poor outcome in dogs with heart failure.

Objectives

To elucidate the vitamin D status of dogs with chronic valvular heart disease (CVHD) at different stages of disease severity.

Animals

Forty‐three client‐owned dogs with CVHD.

Methods

In this cross‐sectional study, dogs were divided into 3 groups (14 dogs in Stage B1, 17 dogs in Stage B2, and 12 dogs in Stage C/D) according to ACVIM guidelines. Dogs underwent clinical examination including echocardiography. Serum 25(OH)D concentrations were measured in each dog.

Results

Serum 25(OH)D concentration was significantly lower in Stage B2 (median, 33.2 nmol/L; range, 4.9–171.7 nmol/L) and C/D (13.1 nmol/L; 4.9–58.1 nmol/L) than in Stage B1 (52.5 nmol/L; 33.5–178.0 nmol/L) and was not significantly different between Stage B2 and Stage C/D. Among clinical variables, there were significant negative correlations between 25(OH)D concentration and both left atrial‐to‐aortic root ratio and left ventricular end‐diastolic diameter normalized for body weight.

Conclusions and Clinical Importance

These results indicate that vitamin D status is associated with the degree of cardiac remodeling, and the serum 25(OH)D concentration begins to decrease before the onset of heart failure in dogs with CVHD.

Current incidence of clinical kernicterus in preterm infants in Japan

Clinical kernicterus in preterm infants has recently been reported in Japan, diagnosed on the basis of clinical findings during the neonatal and infancy periods. We investigated the incidence of clinical kernicterus in preterm infants <30 weeks gestational age (GA) based on a nationwide survey conducted in 233 certified educational facilities for neonatologists. The numbers of infants admitted and infants who died within 14 days after birth during 2011, and the number of infants who subsequently developed clinical kernicterus, were recorded. A total of 2720 infants were analyzed, representing 59% (2720/4623) of all preterm live births <30 weeks GA in Japan in 2011. Of these, 159 (5.8%) died within 14 days after birth, similar to the national rate. Five infants developed clinical kernicterus in infancy (5/2720, 0.18%). The current incidence of clinical kernicterus in Japan is therefore estimated at 1.8 per 1000 live births <30 weeks GA.

Quantitative contrast-enhanced ultrasonographic assessment of naturally occurring pancreatitis in dogs

BACKGROUND

Quantitative contrast-enhanced ultrasonography (CEUS) can detect pancreatic perfusion changes in experimentally induced canine pancreatitis. However, its usefulness in detecting perfusion changes in naturally occurring pancreatitis is unclear.

HYPOTHESIS/OBJECTIVES

To determine the feasibility of using CEUS to detect pancreatic and duodenal perfusion changes in naturally occurring canine pancreatitis.

ANIMALS

Twenty-three client-owned dogs with pancreatitis, 12 healthy control dogs.

METHODS

Dogs diagnosed with pancreatitis were prospectively included. CEUS of the pancreas and duodenum were performed. Time-intensity curves were created from regions of interest in the pancreas and duodenum. Five perfusion parameters were obtained for statistical analyses: time to initial up-slope, peak time (Tp), time to wash-out (TTW), peak intensity (PI), and area under the curve (AUC).

RESULTS

For the pancreas, Tp of the pancreatitis group was prolonged when compared to controls (62 ± 11 seconds versus 39 ± 13 seconds; P < .001). TTW also was prolonged but not significantly (268 ± 69 seconds versus 228 ± 47 seconds; P = .47). PI and AUC were increased when compared to controls (95 ± 15 versus 78 ± 13 MPV; P = .009 and 14,900 ± 3,400 versus 11,000 ± 2,800 MPV*s; P = .013, respectively). For the duodenum, PI and AUC were significantly increased in the pancreatitis group when compared to controls.

CONCLUSIONS AND CLINICAL IMPORTANCE

Contrast-enhanced ultrasonography can detect pancreatic perfusion changes in naturally occurring canine pancreatitis characterized by delayed peak with prolonged hyperechoic enhancement of the pancreas on CEUS. Additionally, duodenal perfusion changes secondary to pancreatitis were observed.

Prognostic value of left atrial function in dogs with chronic mitral valvular heart disease

Background

A strong correlation between left atrial (LA) dysfunction and the severity of cardiac disease has been described in human patients with various cardiac diseases. The role of LA dysfunction in dogs with chronic mitral valvular heart disease (CMVHD) has not been addressed.

Objectives

To investigate the correlation between LA function and the prognosis of dogs with CMVHD.

Animals

Thirty‐eight client‐owned dogs with CMVHD.

Methods

Prospective clinical cohort study. Dogs were divided into 2 groups (survivors and nonsurvivors) based on the onset of cardiac‐related death within 1 year. Physical examination and echocardiographic variables were compared between the groups. For the assessment of the comparative accuracy in identifying patients with cardiac‐related death, receiver operating characteristic (ROC) curves and multivariate logistic analysis were used.

Results

The highest accuracy was obtained for the LA active fractional area change (LA‐FAC_act), with an area under the ROC curve (AUC) of 0.95, followed by the left atrial to aortic root ratio (LA/Ao), with an AUC of 0.94; peak early diastolic mitral inflow velocity (E), with an AUC of 0.85; and LA total fractional area change (LA‐FAC_total), with an AUC of 0.85. In the multivariate logistic regression analysis, LA‐FAC_act emerged as the only independent correlate of cardiac‐related death within 1 year (odds ratio = 1.401, P = .002).

Conclusions and Clinical Importance

Regarding both the size and function, the LA has a strong correlation with the prognosis of dogs with CMVHD. The most significant independent predictor of mortality in this study was LA‐FAC_act.

Low-temperature catalyst activator: mechanism of dense carbon nanotube forest growth studied using synchrotron radiation

The mechanism of the one-order-of-magnitude increase in the density of vertically aligned carbon nanotubes (CNTs) achieved by a recently developed thermal chemical vapor deposition process was studied using synchrotron radiation spectroscopic techniques. In the developed process, a Ti film is used as the underlayer for an Fe catalyst film. A characteristic point of this process is that C2H2 feeding for the catalyst starts at a low temperature of 450°C, whereas conventional feeding temperatures are ∼800°C. Photoemission spectroscopy using soft and hard X-rays revealed that the Ti underlayer reduced the initially oxidized Fe layer at 450°C. A photoemission intensity analysis also suggested that the oxidized Ti layer at 450°C behaved as a support for nanoparticle formation of the reduced Fe, which is required for dense CNT growth. In fact, a CNT growth experiment, where the catalyst chemical state was monitored in situ by X-ray absorption spectroscopy, showed that the reduced Fe yielded a CNT forest at 450°C. Contrarily, an Fe layer without the Ti underlayer did not yield such a CNT forest at 450°C. Photoemission electron microscopy showed that catalyst annealing at the conventional feeding temperature of 800°C caused excess catalyst agglomeration, which should lead to sparse CNTs. In conclusion, in the developed growth process, the low-temperature catalyst activation by the Ti underlayer before the excess Fe agglomeration realised the CNT densification.

Recurrent peritoneal inclusion cysts successfully treated with oral contraceptives: a report of two cases

OBJECTIVE

To examine whether conservative treatment with oral contraceptives is effective in the shrinkage of a peritoneal inclusion cyst (PIC). This is a case report of two patients with a PIC that developed after gynecological surgery.

CASES

Both cases were suspected of a PIC based on the medical history, laboratory data, and image findings. It was difficult in differentiate a PIC from an ovarian tumor. Surgery was chosen at first. However, PICs in both cases recurred after surgery and were treated with oral contraceptives as a conservative treatment. PICs shrank after the treatment of oral contraceptives in both cases.

CONCLUSION

Due to the high rate of recurrence following surgery, conservative treatment is recommended to treat PICs. Hormone therapy using oral contraceptives seems to have some therapeutic benefit for the PICs.