Reappraisal of anatomical liver resection for hepatoblastoma in children

Background

The principle of hepatoblastoma (HB) treatment is complete resection. The removal of tumor-bearing section(s) or hemiliver is widely accepted. However, neither the standardized anterior approach for right hepatectomy nor parenchymal sparing anatomical liver resection has been described for HB.

Methods

We retrospectively reviewed the clinical course of two pediatric HB patients who underwent extended right hepatectomy using the anterior approach with the liver hanging maneuver and one who underwent parenchymal sparing anatomical liver resection of S4 apical+S8 ventral/dorsal+S7. The critical aspects of surgical techniques are described in detail.

Results

In all three patients, R0 resection was achieved without complications and are currently alive without recurrence after an average follow-up of 23 months. Intraoperative cardiac hemodynamics were stable, even in a trisomy 18 patient with cardiac disease.

Conclusions

Our findings suggest that these innovative techniques established in adults are safe and feasible for HB in children. These techniques also allow optimal anatomical liver resection to accomplish curative surgery while maintaining the functional reserve of the remnant liver.

Hepatic venous outflow obstruction after adult living donor liver transplantation

Hepatic venous outflow obstruction (HVOO) is a rare but critical vascular complication after adult living donor liver transplantation. We categorized HVOOs according to their morphology (anastomotic stenosis, kinking, and intrahepatic stenosis) and onset (early-onset < 3 mo vs. late-onset ≥ 3 mo). Overall, 16/324 (4.9%) patients developed HVOO between 2000 and 2020. Fifteen patients underwent interventional radiology. Of the 16 hepatic venous anastomoses within these 15 patients, 12 were anastomotic stenosis, 2 were kinking, and 2 were intrahepatic stenoses. All of the kinking and intrahepatic stenoses required stent placement, but most of the anastomotic stenoses (11/12, 92%) were successfully managed with balloon angioplasty, which avoided stent placement. Graft survival tended to be worse for patients with late-onset HVOO than early-onset HVOO (40% vs. 69.3% at 5 y, p = 0.162) despite successful interventional radiology. In conclusion, repeat balloon angioplasty can be considered for simple anastomotic stenosis, but stent placement is recommended for kinking or intrahepatic stenosis. Close follow-up is recommended in patients with late-onset HVOO even after successful treatment.

Potential involvement of IL-32 in cell-to-cell communication between macrophages and hepatoblastoma

PURPOSE

This study investigated the expression of interleukin 32 (IL-32) in hepatoblastoma, the most common primary pediatric liver tumor, and its possible roles in tumorigenesis.

METHODS

IL-32 expression was investigated in two hepatoblastoma cell lines (Hep G2 and HuH 6) in the steady state and after co-culture with macrophages by RNA-seq analysis and RT-qPCR, and after stimulation with chemotherapy. Cultured macrophages were stimulated by IL-32 isoforms followed by RT-qPCR and western blot analysis. IL-32 immunohistochemical staining (IHC) was performed using specimens from 21 hepatoblastoma patients. Clustering analysis was also performed using scRNA-seq data downloaded from Gene Expression Omnibus.

RESULTS

The IL-32 gene is expressed by hepatoblastoma cell lines; expression is upregulated by paracrine cell-cell communication with macrophages, also by carboplatin and etoposide. IL-32 causes protumor activation of macrophages with upregulation of PD-L1, IDO-1, IL-6, and IL-10. In the patient pool, IHC was positive only in 48% of cases. However, in the downloaded dataset, IL-32 gene expression was negative.

CONCLUSION

IL-32 was detected in hepatoblastoma cell lines, but not in all hepatoblastoma patients. We hypothesized that stimulation such as chemotherapy might induce expression of IL-32, which might be a critical mediator of chemoresistance in hepatoblastoma through inducing protumor activation in macrophages.

Recent advances in surgical strategies and liver transplantation for hepatoblastoma

Hepatoblastoma (HB) is the most common malignant liver tumor in children. Although the development of treatment strategies with advances in chemotherapy has greatly improved the prognosis of HB, surgical resection and liver transplantation still play a vital role in the treatment of HB. In recent years, technological innovations have led to the development of new surgical approaches for HB. In this review, we describe the latest research on the surgical management of HB, including new imaging technologies, minimally invasive approaches, and the application of associating liver partition portal vein ligation for staged hepatectomy. We also discuss the current role of liver transplantation, use of ante-situm or ex-situ liver resection with auto-transplantation, and management of metastatic HB.

Electrophysiological characteristics and catheter ablation of atypical fast-slow atrioventricular nodal reentrant tachycardia using an inferolateral left atrial slow pathway

Background

Understandings of subtypes of atypical atrioventricular nodal reentrant tachycardia (AVNRT) using variants of slow pathway (SP) are still growing. Inferolateral (inf-lat-) left atrial (LA) SP is a rare variant extending into an inf-lat-LA along the mitral annulus (MA).

Purpose

To characterize an unknown subtype of atypical fast-slow (F/S-) AVNRT using an inf-lat-LA-SP as a retrograde limb (inf-lat-LA-F/S-AVNRT).

Methods

This Japanese multicenter retrospective study enrolled 4 patients of inf-lat-LA-F/S-AVNRT that was characterized by the earliest site of atrial activation during tachycardia (EAA) between 3 and 6 o'clock along the MA. The diagnosis was made by an exclusion of AV reentrant tachycardia (AVRT) and atrial tachycardia (AT) according to the standard criteria and was confirmed by successful elimination of tachycardia and the inf-lat-LA-SP.

Results

Surface ECG during tachycardia revealed long RP appearance except one who had short RP due to a short conduction time across the inf-lat-LA-SP. During tachycardia, far-field LA activation preceding near-field activation of coronary sinus (CS) musculature was visible in the CS recording in 2. Retrograde conduction via the inf-lat-LA-SP with a decremental delay was consistently reproducible with ventricular stimulation in 2, 1 of whom had double atrial response, while it was always masked by the presence of a retrograde conduction via the fast pathway in 1 and a retrograde block at the lower common pathway in 1. An injection of a small dose of ATP transiently interrupted a retrograde conduction over the inf-lat-LA-SP, suggesting its ATP-sensitivity. Exclusion of AVRT was made by no resetting of tachycardia with left ventricular extrastimulus in 2 and VA dissociation during overdrive pacing of tachycardia in remaining 2. Exclusion of AT was made by V-A-V response after ventricular entrainment in 1 and termination without atrial capture by ventricular pacing in 2. Ablation of the right-sided SP was unsuccessful to eliminate the tachycardia, but ablation at or near the EAA by transseptal approach was successful to cure the tachycardia, associated with an elimination of a retrograde conduction over the inf-lat-LA-SP following a development of an accelerated junction rhythm in all. Low-frequency potentials preceding local atrial activation, consistent with a retrograde activation via the inf-lat-LA-SP were detected along the MA medial to the EAA in 1.

Conclusions

Differential diagnosis of tachycardia with the EAA in the inf-lat-LA and especially long RP appearance should include inf-lat-LA-F/S-AVNRT. Presumed arrhythmogenic substrate of the inf-lat-LA-SP seemed to be consistent with the remnant of embryogenic AV ring tissue in the electropharmacological and locational characteristics. Successful elimination of this AVNRT can be obtained by ablation of the inf-lat-LA-SP, but not of the right-sided SP.

Funding Acknowledgement

Type of funding sources: None.

M-CSFR expression in the embryonal component of hepatoblastoma and cell-to-cell interaction between macrophages and hepatoblastoma

Tumor-associated macrophages (TAMs) have protumor functions in various cancers. However, their significance in hepatoblastoma, the most common liver tumor in children, remains unclear. The aim of this study was to explore the potential roles of TAMs in hepatoblastoma. Immunohistochemical analysis revealed that the density of CD204-positive TAMs was significantly higher in the embryonal component than in other histological subtypes of hepatoblastoma. An in vitro co-culture study with Huh6 cells and human monocyte-derived macrophages (HMDMs) showed that macrophage-colony-stimulating factor receptor (M-CSFR) was strongly up-regulated in the Huh6 cells that were directly co-cultured with HMDMs. The expressions of M-CSFR ligands (interleukin-34 and M-CSF) were also increased by co-culture with HMDMs. The proliferation of HepG2 cells (another hepatoblastoma cell line expressing M-CSFR) was inhibited by an M-CSFR inhibitor. M-CSFR was found to be highly expressed in the embryonal component and in recurrent lesions. The number of CD204-positive macrophages was also higher in the M-CSFR-positive areas than in the M-CSFR-negative areas. Thus, M-CSFR expression appeared to be induced by cell-cell contact with macrophages in hepatoblastoma cells, and M-CSFR inhibitor is potentially effective against M-CSFR-positive hepatoblastoma, especially recurrent cases.

IL-34 in hepatoblastoma cells potentially promote tumor progression via autocrine and paracrine mechanisms

Hepatoblastoma is the most common pediatric liver tumor, but little research has been done on the role of macrophages in hepatoblastoma. The purpose of this study was to gain insight into potential roles for macrophages in hepatoblastoma. Paraffin‐embedded specimens from 56 patients who underwent surgical resection were examined with immunohistochemical staining for the macrophage‐specific markers, Iba1 and CD163. Significant differences were seen among histological subtypes. Significantly increased numbers of macrophages were detected in embryonal components compared to fetal components in the mixed epithelial type. In vitro studies using human monocyte‐derived macrophages and two hepatoblastoma cell lines (HepG2 and Huh6) were performed. Conditioned medium from these cell lines induced increased CD163 expression in macrophages. Direct co‐culture with macrophages induced tumor cell proliferation via induction of protumor cytokine secretion from macrophages. Direct co‐culture with macrophages also induced interleukin (IL)‐34 overexpression by Huh6 cells via Brd4 signaling. IL‐34 overexpression promoted tumor cell proliferation and chemoresistance. High IL‐34 and Brd4 expression was detected in embryonal components, which have potentially higher proliferation activity than fetal components. In conclusion, IL‐34 expression in embryonal components may induce macrophage chemotaxis in a paracrine manner, and tumor cell proliferation and chemoresistance in an autocrine manner. IL‐34 is a potential therapeutic target for hepatoblastoma.

Intellectual development of patients with biliary atresia who underwent living donor liver transplantation in infancy

BACKGROUND

The impact of pediatric liver transplantation on intellectual development has yet to be determined. We investigated the intellectual outcomes of school-aged patients after living donor liver transplantation for biliary atresia in infancy.

METHODS

The Wechsler Intelligence Scale for Children-fourth edition test was administered to 20 patients who survived [Formula: see text] 5 years after living donor liver transplantation. Borderline full scale intelligence quotient was defined as ≤ 85. Pre-, peri-, and postoperative data were compared between patients with > 85 and ≤ 85 to identify predictive factors of borderline performance.

RESULTS

The one-sample t test demonstrated that the mean full scale intelligence quotient of patients after transplantation for biliary atresia was significantly lower than that of the general population (91.8 vs. 100.0, p = 0.026) and 7 (35%) were classified as intellectual borderline functioning. Multivariable logistic regression models were unable to identify any factors predictive of full scale intelligence quotients of ≤ 85.

CONCLUSION

This is the first study to indicate that the mean full scale intelligence quotient among school-aged patients who underwent living donor liver transplantation for biliary atresia in infancy is significantly lower than that of the general population.

Portal Vein Complications After Adult Living Donor Liver Transplantation: Time of Onset and Deformity Patterns Affect Long-Term Outcomes

Portal vein complications (PVCs) after adult living donor liver transplantation (LDLT) are potentially lethal. We categorized PVCs by the time of onset (early versus late, <1 month versus ≥1 month, respectively) and deformity patterns (portal vein stenosis [PVS], portal vein thrombosis [PVT], and portal vein occlusion [PVO]) to establish optimal treatment strategies. Overall, 35/322 (10.9%) recipients developed PVCs between 2000 and 2019. Pretransplant PVT (odds ratio [OR], 15.20; 95% confidence interval [CI], 3.70-62.40; P < 0.001) was the only independent risk factor for PVS. In contrast, male sex (OR, 5.57; 95% CI, 1.71-18.20; P = 0.004), pretransplant PVT (OR, 4.79; 95% CI, 1.64-14.00; P = 0.004), and splenectomy (OR, 3.24; 95% CI, 1.23-8.57; P = 0.018) were independent risk factors for PVT. PVS was successfully treated with interventional radiology regardless of its time of onset. On the other hand, late PVT and PVO had significantly lower treatment success rates (2/15, 13%) compared with those that occurred in the early period (10/11, 91%) despite aggressive intervention (P < 0.001). Deformity patterns had a significant impact on the 5-year cumulative incidence of graft loss as a result of PVC (PVO + Yerdel grades 2-4 PVT group [n = 16], 41% versus PVS + Yerdel grade 1 PVT group [n = 19], 0%; P = 0.02). In conclusion, late grades 2 to 4 PVT and PVO are refractory to treatment and associated with poor prognoses, whereas PVS has a good prognosis regardless of time of onset. A tailored approach according to the time of onset and deformity patterns of PVC is essential.

Asymptomatic hepatic artery dissection early after living-donor liver transplantation with simultaneous splenectomy: two case reports

Background

Hepatic artery dissection after liver transplantation is an uncommon morbidity. The onset mechanism and management for this disorder remain unclear. The present report describes the cases of two patients with hepatic artery dissection after living-donor liver transplantation (LDLT) with simultaneous splenectomy and provides new insight into the onset mechanism of this disorder.

Case presentation: Case 1

A 51-year-old man with liver cirrhosis caused by hepatitis B virus underwent LDLT with a right lobe graft and splenectomy simultaneously. The recipient’s right hepatic artery had partial dissection at the anastomosis site; therefore, his left hepatic artery was anastomosed. Contrast-enhanced computed tomography (CT) on postoperative day (POD) 27 showed dissection from his celiac artery to his left hepatic artery with bleeding in the false lumen. There was a risk of rupture of the false lumen; therefore, emergency interventional radiology and coil embolization of the false lumen were performed. The patient was doing well at 6 months after LDLT.

Case 2

A 58-year-old woman with liver cirrhosis caused by primary biliary cholangitis underwent LDLT with a left lobe graft and splenectomy simultaneously. Her hepatic artery had a dissection that extended from her left hepatic artery to the proper hepatic artery. The gastroduodenal artery was anastomosed. Contrast-enhanced CT on POD 8 revealed dissection from the celiac artery to the common hepatic artery as well as a pseudoaneurysm at the celiac artery. We managed the patient with conservative treatment and performed daily follow-ups with Doppler ultrasonography examination and serial contrast-enhanced CT. At the time of writing this report, the patient was doing well at 34 months after LDLT.

Conclusions

Patients who have an intimal dissection at the anastomosis site and/or simultaneous splenectomy are at a higher risk of hepatic artery dissection. Most patients with asymptomatic hepatic artery dissections can be treated conservatively. Blood flow in the intrahepatic artery should be checked frequently using Doppler ultrasonography or contrast-enhanced CT soon after diagnosis.

The duodenal tube test is more specific than hepatobiliary scintigraphy for identifying bile excretion in the differential diagnosis of biliary atresia

PURPOSE

Confirmation of bile excretion into the gastrointestinal tract is important to exclude biliary atresia (BA). We compared the duodenal tube test (DTT) with hepatobiliary scintigraphy (HS) for their efficiency in detecting bile secretion.

METHODS

The subjects of this retrospective study were 47 infants who underwent both DTT and HS to diagnose or exclude BA between January 2000 and March 2018.

RESULTS

BA was diagnosed in 32 of the 47 patients, and 7 of the remaining 15 non-BA patients underwent intraoperative cholangiography. Among the various DTT parameters, the total bile acid in duodenal fluid (DF-TBA)/serum (S) gamma-glutamyl transferase (γGTP) ratio was found to be the most specific for BA, with sensitivity and specificity of 98.0-100%, respectively. One BA patient in whom cut off values were not met was a premature infant. The sensitivity and specificity of HS were 100-56.3%, respectively. The diagnostic accuracy of the DF-TBA/S-γGTP parameter was higher than that of HS (98.6% vs. 85.1%, respectively).

CONCLUSIONS

The DTT could be more a specific method than HS to detect bile excretion. Thus, the DTT should be incorporated into the multidisciplinary diagnostic approach for the differential diagnosis of BA to prevent unnecessary intraoperative cholangiography in patients who do not have BA.

Single-center Experience of Living-donor Liver Transplantation in Patients Receiving Maintenance Renal Replacement Therapy

BACKGROUND

For most patients with liver failure receiving maintenance renal replacement therapy (RRT), treatment with living-donor liver transplantation (LDLT) alone is indicated in Japan.

MATERIAL AND METHODS

We retrospectively reviewed patients who underwent LDLT while receiving RRT in our hospital.

RESULTS

Three of the 5 patients who underwent LDLT while on RRT died during the first year after transplantation.

CONCLUSIONS

The indications for liver transplantation in patients on RRT require careful examination.

Living donor liver transplantation for a patient with a history of total gastrectomy

Adhesions due to previous upper abdominal surgery may complicate later liver transplantation. Here we report successful living donor liver transplantation (LDLT) in a patient with a history of total gastrectomy. A 32-year-old Japanese woman developed end-stage liver failure due to alcoholic cirrhosis. She had undergone total gastrectomy, pancreato-splenectomy, and partial colectomy due to rupture of a pancreatic cyst. LDLT was performed using a right lobe graft from her sister. To minimize blood loss and injury to the jejunum, adhesions between the left lobe and nearby organs were dissected without blood flow in or out of the liver. The right liver graft was implanted uneventfully. She was extubated on postoperative day (POD) 1, but then developed septic shock due to aspiration pneumonia on POD 2. She was reintubated and antibiotics and antifungal agents were administered. Administration of tacrolimus was changed to an intravenous route on POD 3. Her condition improved and she was re-extubated on POD 9. On POD 14, tacrolimus was administered orally. She was discharged from our hospital on POD 30 without any other events and is doing well 6 months after LDLT. We believe that careful planning, such as mobilizing the left lobe with the blood flow blocked just before liver explantation, elevating the head of the bed during tube-feeding, and calculating the area under the curve after drug administration will enable liver transplantation for patients with a history of total gastrectomy.

Hypogenesis of right hepatic lobe in a laparoscopic cholecystectomy for acute gallstone cholecystitis: A case report

Hypogenesis or agenesis of right hepatic lobe is a rare abnormality and is generally associated with gallbladder and biliary tract abnormalities. Cases of biliary injury following cholecystectomy have been reported in patients with agenesis of right hepatic lobe because the anatomical anomalies complicate the surgical approach. We report a case of laparoscopic cholecystectomy in a patient with hypogenesis of right hepatic lobe. A 92-year-old male patient was admitted to our hospital with fever and right lower abdominal pain with suspected acute appendicitis. Abdominal computed tomography revealed gallstones with acute cholecystitis and hypogenesis of right hepatic lobe. He underwent laparoscopic cholecystectomy with the left semilateral decubitus position. The patient's postoperative course was uneventful. In conclusions, some patients with liver lobe hypoplasia do not present with the typical symptoms of acute cholecystitis due to dislocation of the gallbladder. The left semilateral decubitus position with modified placement of port sites is useful for laparoscopic cholecystectomy in patients with hypogenesis of right hepatic lobe.

Gene Expression Profiling of Mouse Condylar Cartilage during Mastication by Means of Laser Microdissection and cDNA Array

Little is known about the mechanisms of mandibular condylar growth. In this study, gene expression in the mandibular condylar cartilage of young post-natal mice was monitored by means of a cDNA microarray, real-time PCR, and laser microdissection before and after the initiation of mastication (newborn, 7 days, 21 days, initiation of mastication, and 35 days). Insulin-like growth factor-1 (IGF-I), transforming-growth-factor-beta-2 (TGFbeta2), and aggrecan mRNAs were clearly expressed at 21 days, while the expression of osteopontin mRNAs was most clear at 35 days. Parathyroid-hormone-related protein (PTHrP), Indian-hedgehog (Ihh), and insulin-like growth factor-2 (IGF-2) mRNAs were clearly expressed during lactation (newborn and 7 days). Heat-shock-protein 84 (HSP-84) and heat-shock-protein 86 (HSP-86) were clearly expressed at 35 days. These results revealed that gene expression changed during mandibular condylar cartilage growth, and that, interestingly, these changes coincided with the initiation of mastication.

Antibody-mediated rejection after ABO-incompatible pediatric living donor liver transplantation for propionic acidemia: A case report

We herein present the case of a four-yr-old boy with PA who developed AMR after ABO-incompatible LDLT despite undergoing B cell desensitization using rituximab. Although the CD19+ lymphocyte count decreased to 0.1% nine days after the administration of rituximab, he developed a high fever which was accompanied by arthralgia due to a streptococcal infection 13 days after rituximab prophylaxis. After the clearance of the infection, he underwent ABO-incompatible LDLT 36 days after the administration of rituximab. The CD19+ lymphocyte count just prior to LDLT was 1.2%. He developed AMR five days after LDLT, and the antidonor-type IgM and IgG antibody titers increased to 1:1024 and 1:1024, respectively. He was treated by plasma exchange, IVIG, steroid pulse therapy, and rituximab re-administration; however, his liver dysfunction continued. Despite intensive treatment, he died due to complicated abdominal hernia, acute renal failure, and ARDS. This case suggests that a streptococcal infection may induce the activation of innate immune responses; thus, additional desensitization therapy should be considered prior to ABO-incompatible LDLT if B cell reactivation is suspected.

A One-Stage Method for Obtaining CT during Arterial Portography and Hepatic Arteriography

We describe a new technique for performing CT during arterial portography (CTAP) and during hepatic arteriography (CTHA) in a one-stage procedure, using a coaxial balloon catheter system and slip-ring CT equipment. This technique was employed in 10 patients with liver neoplasms. Both CTAP and CTHA images were obtained in all patients.

Prediction of the Time to Peak Hepatic Enhancement to Optimize Contrast-Enhanced Spiral CT

A technique for the prediction of the time to peak hepatic enhancement to optimize contrast-enhanced spiral CT has been developed. The procedures are (a) to inject a small amount of contrast medium rapidly via the antecubital vein and measure aortic transit time (ATT) of the bolus by single slice dynamic CT; (b) to inject contrast medium at a high rate, expecting peak hepatic enhancement to occur at ATT plus 8 seconds after the end of injection; (c) to perform spiral scanning of the liver using thin collimation and caudo-cranial table movement beginning at ATT after the end of contrast medium injection.

Partial Splenic Embolization with Y-Shaped Silicone Particles

We have developed an embolizing material consisting of Y-shaped silicone particles for partial splenic embolization. Wide spaces for blood flow are left around the particles when these are lodged in arterial branches. We embolized one kidney in each of 3 dogs with the particles and observed a slowly induced occlusion of renal arterial branches during one month. The particles were also used for partial splenic embolization in 14 patients. The average portion of infarcted spleen tissue 7 days after embolization was 51% calculated from CT images. In 6 patients who had CT both 2 and 7 days after embolization, the average rate of splenic infarction increased from 29% at 2 days to 60% at 7 days. Our patients required analgesics for only 2.3 days on average. The Y-shaped silicone particles by slowly occluding splenic arterial branches produce ischemia in a gradual fashion which may minimize the pain after embolization.

Regression of gastric de novo diffuse large B-cell lymphoma following Helicobacter pylori eradication: a case report

We report a case of primary gastric diffuse large B-cell lymphoma (DLBCL), de novo DLBCL without the features of mucosa-associated lymphoid tissue (MALT) lymphoma, which regressed after Helicobacter pylori (HP) eradication. A 27-year-old Japanese female with epigastralgia was revealed to have ulcerated lesions in the angle and antral regions on gastroscopy. Biopsy specimen was consistent with a diagnosis of DLBCL without MALT lymphoma component, indicating de novo development. Her clinical staging on the Lugano system was Stage I. HP was positive on a rapid urease test, and she received HP eradication therapy twice, because the first therapy was not successful. On gastroscopy performed 1 month after the second HP eradication therapy, no ulcerated lesion was noted, and the lymphoma cells had regressed histopathologically. (Acta gastro-enterol. belg., 2016, 79, 367-369A).

Dementia with Lewy bodies can be well-differentiated from Alzheimer's disease by measurement of brain acetylcholinesterase activity-a [11C]MP4A PET study

OBJECTIVE

To investigate the diagnostic performance of brain acetylcholinesterase (AChE) activity measurement using N-[(11) C]-methyl-4-piperidyl acetate (MP4A) and PET in patients with dementia with Lewy bodies (DLB) and Alzheimer's disease (AD).

METHODS

Participants were 14 DLB patients, 25 AD patients and 18 age-matched healthy controls (HC). All subjects underwent PET scans and MP4A to measure regional brain AChE activity. We performed anatomical standardization of each brain image, and k3 values, an index of AChE activity, in each voxel were estimated by nonlinear least squares analysis. Volumes of interest (VOIs) were identified on parametric k3 images in frontal, temporal, parietal and occipital cortices, and in anterior and posterior cingulate gyri (ACG and PCG). In each VOI, the differential diagnostic performance between AD and DLB of k3 values was assessed by area under the curve (AUC) of the receiver-operating characteristic. Voxel-based statistical analyses were also performed.

RESULTS

Mean cortical AChE activities in AD patients (-8.2% compared with normal mean) and DLB patients (-27.8%) were lower than HCs (p < 0.05, p < 0.001, respectively). There was a significant difference in mean cortical AChE activities between AD and DLB patients (p < 0.001). All regional brain AChE activities of defined VOIs except ACG were able to well discriminate DLB from AD, and notably performance was the most significant in PCG (AUC = 0.989, 95% CI: 0.965-1.000).

CONCLUSIONS

Brain cholinergic deficit is consistently prominent in DLB compared with AD. PET measurement of brain AChE activity may be useful for the differential diagnosis between DLB and AD.

Differences in the developmental origins of the periosteum may influence bone healing

BACKGROUND AND OBJECTIVE

The jaw bone, unlike most other bones, is derived from neural crest stem cells, so we hypothesized that it may have different characteristics to bones from other parts of the body, especially in the nature of its periosteum. The periosteum exhibits osteogenic potential and has received considerable attention as a grafting material for the repair of bone and joint defects.

MATERIAL AND METHODS

Gene expression profiles of jaw bone and periosteum were evaluated by DNA microarray and real-time polymerase chain reaction. Furthermore, we perforated an area 2 mm in diameter on mouse frontal and parietal bones. Bone regeneration of these calvarial defects was evaluated using microcomputed tomography and histological analysis.

RESULTS

The DNA microarray data revealed close homology between the gene expression profiles within the ilium and femur. The gene expression of Wnt-1, SOX10, nestin, and musashi-1 were significantly higher in the jaw bone than in other locations. Microcomputed tomography and histological analysis revealed that the jaw bone had superior bone regenerative abilities than other bones.

CONCLUSION

Jaw bone periosteum exhibits a unique gene expression profile that is associated with neural crest cells and has a positive influence on bone regeneration when used as a graft material to repair bone defects. A full investigation of the biological and mechanical properties of jaw bone as an alternative graft material for jaw reconstructive surgery is recommended.

Lin28a is a putative factor in regulating cancer stem cell-like properties in side population cells of oral squamous cell carcinoma

Cancer stem cells (CSCs) are among the target cells of cancer therapy because they are uniquely involved in both cancer progression and sensitivity to chemotherapeutic agents. We identified side population (SP) cells, which are known to be an enriched population of CSC, in five oral squamous cell carcinoma (OSCC) cells (SCC9, SCC25, TOSCC7, TOSCC17, and TOSCC23). The percentages of SP cells ranged from 0% to 3.3%, with TOSCC23 cells showing the highest percentages of SP cells (3.3% of the total cell population). The SP cells isolated from TOSCC23 cells also showed greater cell proliferation and invasion compared to non-SP (MP) cells. Therefore, our initial findings suggested that SP cells were enriched for CSC-like cells. Furthermore, DNA microarray analysis revealed that the expression of cell proliferation-related and anti-apoptotic genes was greater in SP cells compared to MP cells. We focused on Lin28a, which showed the highest expression (approximately 22-fold) among the upregulated genes. The overexpression of Lin28a in TOSCC23 cells increased their proliferation, colony formation, and invasion. These findings suggest that Lin28a is an appropriate CSC target molecule for OSCC treatment.

Improved transdermal delivery of prostaglandin E1 through hairless mouse skin: combined use of carboxymethyl-ethyl-β-cyclodextrin and penetration enhancers

The optimal prescription of transdermal preparations of prostaglandin E1 (PGE1) for treatment of peripheral vascular diseases has been investigated. The chemical stability of PGE1 in fatty alcohol/propylene glycol (FAPG) ointment was markedly improved by carboxymethyl-ethyl-β-cyclodextrin (CME-β-CyD). Application of a PGE1 ointment containing the penetration enhancer, 1-dodecylazacycloheptane-2-one (Azone) or 1-[2-(decylthio)ethyl]azacyclopentane-2-one (HPE-101), onto the skin of hairless mice showed the increase of blood flow in the skin due to the vasodilating action of PGE1. In particular, the ointment containing a PGE1-CME-β-CyD complex supplemented with HPE-101 showed the most prominent increase of the blood flow. Compared with other ointments, this ointment was found to show significantly greater transfer of HPE-101 into in-vitro preparations of the skin of hairless mice. Transfer of PGE1 into the skin was thought to be facilitated by this increased transfer of HPE-101. These results suggest that a combination of CME-β-CyD and HPE-101 is useful for designing PGE1 ointments for topical application with good chemical stability and percutaneous permeability.

PET imaging of MRP1 function in the living brain: method development and future perspectives

Multidrug resistance-associated protein 1 (MRP1) functions as a primary active transporter utilizing energy from ATP hydrolysis. In the central nervous system (CNS), MRP1 plays an important role in limiting the permeation of xenobiotic and endogenous substrates across the blood-brain and blood-cerebrospinal fluid barriers, and across brain parenchymal cells. While MRP1 contributes to minimizing the neurotoxic effects of drugs, it may also restrict the distribution of drugs for the treatment of CNS diseases. Moreover, neurodegenerative disease may be associated with abnormal expression of efflux transporters in the brain. Noninvasive measurement of MRP1 function will therefore be useful for directly evaluating the effect of modulators on enhancing the penetration of drugs into the brain and for examining the pathophysiological role of MRP1 in the brain. Positron emission tomography (PET) is a powerful molecular imaging technique. While several PET probes have been proposed for imaging function of the efflux transporter P-glycoprotein, few reports discuss the probes for imaging MRP1 function in the brain. Ideally, brain radioactivity should consist of a single radioactive compound that is selectively transported by the efflux transporter of interest, without other efflux routes. However, most PET probes for MRP1 or P-glycoprotein are eliminated by both a transporter and simple diffusion, resulting in inaccurate measurement of pump function. This review addresses a new strategy to avoid this problem, and suggests the design of a PET probe based on this strategy, particularly for MRP1 imaging. Several published reports on imaging MRP1 function with PET are also discussed.

Mapping of brain acetylcholinesterase alterations in Lewy body disease by PET

OBJECTIVE

To characterize brain cholinergic deficits in Parkinson disease (PD), PD with dementia (PDD), and dementia with Lewy bodies (DLB).

METHODS

Participants included 18 patients with PD, 21 patients with PDD/DLB, and 26 healthy controls. The PD group consisted of nine patients with early PD, each with a disease duration of less than 3 years, five of whom were de novo PD patients, and nine patients with advanced PD, each with a disease duration greater than or equal to 3 years. The PDD/DLB group consisted of 10 patients with PDD and 11 patients with DLB. All subjects underwent PET scans with N-[11C]-methyl-4-piperidyl acetate to measure brain acetylcholinesterase (AChE) activity. Brain AChE activity levels were estimated voxel-by-voxel in a three-compartment analysis using the arterial input function, and compared among our subject groups through both voxel-based analysis using the statistical parametric mapping software SPM5 and volume-of-interest analysis.

RESULTS

Among patients with PD, AChE activity was significantly decreased in the cerebral cortex and especially in the medial occipital cortex (% reduction compared with the normal mean = -12%) (false discovery rate-corrected p value <0.01). Patients with PDD/DLB, however, had even lower AChE activity in the cerebral cortex (% reduction = -27%) (p < 0.01). There was no significant difference between early PD and advanced PD groups or between DLB and PDD groups in the amount by which regional AChE activity in the brain was reduced.

CONCLUSIONS

Brain cholinergic dysfunction occurs in the cerebral cortex, especially in the medial occipital cortex. It begins in early Parkinson disease, and is more widespread and profound in both Parkinson disease with dementia and dementia with Lewy bodies.

Cost benefit and clinical efficacy of low-dose granulocyte colony-stimulating factor after standard chemotherapy in patients with non-Hodgkin's lymphoma

High costs of molecule-targeted drugs, such as rituximab, ibritumomab, and tositumomab have given rise to an economical issue for treating patients with non-Hodgkin's lymphoma (NHL). Granulocyte colony-stimulating factors (G-CSFs), which are also expensive, are widely used for treating neutropenia after chemotherapy. In Japan, lenograstim at 2 microg/kg (about 100 microg/body) or filgrastim at 50 microg/m(2) (about 75 microg/body) is commonly administered for patients with NHL after chemotherapy. Therefore, cost-effectiveness is an important issue in treatment for NHL. Patients with advanced-stage NHL who needed chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or a CHOP-like regimen with or without rituximab were enrolled in this randomized cross-over trial to investigate the efficacy and safety of low-dose G-CSF. Half of the patients were administered 75 microg filgrastim in the first course after neutropenia and 50 microg lenograstim in the second course, and the other half were crossed over. Forty-seven patients were enrolled in this cross-over trial, and 24 patients completed the trial. Frequencies and durations of grade 4 leukocytopenia and neutropenia were similar in the two groups. Severe infection was rare and was observed at similar frequency. Frequencies of antibiotics use were also similar. The total cost of G-CSF (cost/drug x duration of administration) was significantly lower in patients who received 50 microg lenograstim. Hence, a low dose of lenograstim might be safe, effective and pharmaco-economically beneficial in patients with advanced-stage NHL.

[Lung abscess which ruptured during the medical treatment of lung abscess; report of a case]

63-year-old man was admitted to our hospital with fever and cough for about 2 months. Laboratory data showed marked inflammatory changes, and chest computed tomography (CT) scans revealed right-sided hydrothorax, atelectasis of the right middle lobe, and a cystic mass in the right middle lobe. We diagnosed the patients as having lung abscess and empyema. Following the intravenous antibiotic chemotherapy, symptoms and laboratory data showed the improvement, however, on the 11th hospital day, he developed high fever again. A chest CT showed pneumopyothorax suggesting the rupture of lung abscess. Since the chest tube drainage was ineffective, open chest surgery was performed. Curettage of both thoracic and abscess cavity with closure of air leakage successfully cured the pyothorax.

Chitosan-based hyaluronan hybrid polymer fibre scaffold for ligament and tendon tissue engineering

To establish medical use of tissue engineering technology for ligament and tendon injuries, a scaffold was developed which has sufficient ability for cell growth, cell differentiation, and mechanical properties. The scaffold made from chitosan and 0.1 per cent hyaluronic acid has adequate biodegradability and biocompatibility. An animal experiment showed that the scaffold has less toxicity and less inflammation induction. Furthermore, in-vivo animal experiments showed that the mechanical properties of the engineered ligament or tendon had the possibility to stabilize the joint. It was shown that newly developed hybrid-polymer fibre scaffold has feasibility for joint tissue engineering.

The role of sex hormones in the kinetics of chondrocytes in the growth plate

Sex hormones play important roles in the regulation of the proliferation, maturation and death of chondrocytes in the epiphyseal growth plate. We have investigated the effects of male castration on the cell kinetics of chondrocytes as defined by the numbers of proliferating and dying cells. The growth plates of normal rabbits and animals castrated at eight weeks of age were obtained at 10, 15, 20 and 25 weeks of age.

Our study suggested that castration led to an increase in apoptosis and a decrease in the proliferation of chondrocytes in the growth plate. In addition, the number of chondrocytes in the castrated rabbits was less than that of normal animals of the same age.