Lessons learned from an outbreak of COVID-19 in the head and neck surgery ward of a Japanese cancer center during the sixth wave by Omicron.

INTRODUCTION: We describe a coronavirus disease (COVID-19) outbreak in a cancer center's head and neck surgery ward and the interventions to halt ongoing exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among healthcare workers and patients with cancer. METHODS: Case definition included all healthcare workers and all patients associated to the ward from January 27 to January 31, 2022 with a positive SARS-COV-2 antigen test. This retrospective descriptive study was conducted between January 27, 2022, and February 14, 2022. RESULTS: From January 28, 2022, to February 9, 2022, 84 cases (36 healthcare workers, 48 patients) were screened, and 26 (12 healthcare workers, 14 patients) were identified as SARS-CoV-2-positive. The proportion of healthcare providers who performed aerosol generating procedures on positive patients was 91% for positive cases and 49% for non-cases. Room sharing with patients with COVID-19 was 64% for positive cases and 21% for non-cases (57% vs. 21% with positive tracheostomy patients; 43% vs. 9% with positive cases using a nebulizer; 50% vs. 15% with positive cases requiring sputum suctioning, respectively). Compliance with the universal masking policy for patients was 36% of positive cases and 79% of non-cases. CONCLUSIONS: This is the first report of a nosocomial outbreak of COVID-19 in a head and neck surgery ward during the Omicron pandemic. Notably, there were a high number of positive cases among healthcare workers who performed aerosol generating procedures for positive patients and patients who shared the room with a patient with COVID-19 with the potential to generate aerosols.

Cervical lateral mass screw length analysis in men versus women.

Posterior fixations with lateral mass screws have become popular. The Roy-Camille and the Magerl techniques have been established and screw length was identified as a particularly important element. Sex and ethnicity are significant factors in cervical spine morphology, but few studies have been performed for screw length. We performed measurements using computed tomography (CT) images of adult patients hospitalized for surgery of the cervical spine, with targeted 3D data analysis. The final number of patients was 47 (33 men, 14 women) and 235 vertebrae. With the Roy-Camille technique, the screw length was longest at C3 (men: 13.0 mm ± 1.9 mm, women: 13.0 mm ± 1.9 mm) and smallest at C7 (men: 10.8 mm ± 1.8 mm, women: 9.4 mm ± 1.2 mm). With the Magerl technique, the screw length was smallest at C3 (men: 14.8 mm ± 1.6 mm, women: 14.3 mm ± 1.6 mm) and longest at C7 for men (16.8 mm ± 2.8 mm), and at C6 for women (15.4 mm ± 3.0 mm). To differ from spinal canal or pedicle, cervical lateral mass showed no obvious morphological differences from that of subjects of other ethnicity. The placement of a standard lateral mass screw would not cause complications in Japanese patients, even with the use of devices designed in North America or Europe. However, the anatomical background is essential because it is important to optimize the selection for each patient to avoid complications considering sex and individual differences.

MRI characteristics of syringomyelia associated with foramen magnum arachnoiditis: differentiation from Chiari malformation.

BACKGROUND: It is important to distinguish foramen magnum arachnoiditis (FMA) from Chiari malformation (CM) before surgery because the operative strategies for these diseases differ. In the current study, we compared pretreatment magnetic resonance imaging (MRI) of FMA with CM and investigated the MRI findings useful to differentiate between these diseases. METHODS: We retrospectively reviewed patients with FMA or CM aged ≥ 18 years who underwent surgeries at our institution between 2007 and 2019. The morphologies of the syrinx, neural elements, and posterior cranial fossa were preoperatively evaluated with MRI. We used the receiver operating characteristic (ROC) curve for the fourth ventricle-to-syrinx distance (FVSD). RESULTS: Ten patients with FMAs and 179 with CMs were included. FVSD in the FMA group was significantly shorter than that in the CM group (7.5 mm [IQR, 2.8-10 mm] in FMA vs. 29.9 mm [IQR, 16.3-52.9 mm] in CM, p < 0.0001). The other MRI findings that showed the height, size, and length of the syrinx; size of the foramen magnum; degree of cerebellar tonsillar descent; shape of the cerebellar tonsil; and dorsal subarachnoid space at the foramen magnum differed significantly between the two groups. The ROC curve analysis showed that patients whose FVSD was less than 11 mm could be diagnosed with FMA with a specificity of 90% and sensitivity of 96%. CONCLUSIONS: A more cranial syrinx development (FVSD < 11 mm) appears to be the characteristic MRI finding in FMA.

Thoracic and lumbar spine pedicle morphology in Japanese patients.

PURPOSE: Pedicle morphology is important for intraoperative surgical anatomy and to define pedicle screw design and parameters. However, differences of pedicle size according to ethnicity and gender are not well studied. The purpose of this study is to investigate morphological characteristics of the pedicle in Japanese patients for determining adequate screw size and optimal surgical planning. METHODS: We investigated thoracic and lumbar pedicle morphology in Japanese patients using computed tomography (CT) measurements and analyzed the standard size of pedicles on upper thoracic to lumbar spine CT images in 227 Japanese patients. RESULTS: Gender had a larger impact on the shape and size of pedicles than racial differences. In the distribution of pedicle width, we calculated the ratio of values less than 4.5 mm, that in females resulted to be over 30% for the Th3-Th9 segment, and particularly high, above 60% at Th4 and Th5. CONCLUSION: Our measurement analysis showed that pedicle morphological parameters in Japanese patients showed tendency to be smaller to those found in other studies, and particularly in female patients, they were statistically significantly smaller. Adequate transpedicular instrumentation for Japanese patients will require smaller size pedicle-related devices that will match our anatomical findings to achieve safe device placement. In addition, serving ethnically non-homogenous patient population can require further to spinal morphometric for precise device selection.

Reduction strategies for inpatient oral third-generation cephalosporins at a cancer center: An interrupted time-series analysis.

Oral third-generation cephalosporins (3GCs) are not recommended for use owing to their low bioavailability and the risk of emergence of resistant microorganisms with overuse. A standardized and effective method for reducing their use is lacking. Here, in a 60-month, single-institution, interrupted time-series analysis, which was retrospectively conducted between April 1, 2017, and March 31, 2022, we evaluated the effectiveness of a four-phase intervention to reduce the use of 3GCs in patients at a cancer center: Phase 1 (pre-intervention), Phase 2 (review of clinical pathways), Phase 3 (establishment of infectious disease consultation service and implementation of antimicrobial stewardship program), and Phase 4 (educational lecture and pop-up displays for oral antimicrobials at the time of ordering). Although no significant changes were observed in Phases 3 and 4, the first intervention resulted in a significant decrease in the trend and level of days of therapy (DOT) for 3GCs. The level for cephalexin DOT and the trend for sulfamethoxazole-trimethoprim DOT increased in Phase 4, and the trend for amoxicillin and amoxicillin-clavulanate DOT increased in Phase 3. Macrolide DOT showed a decreasing trend in Phases 2 and 4 and decreasing and increased levels in Phases 3 and 4, respectively; no change was observed for quinolones. Actual and adjusted purchase costs of 3GCs decreased significantly during all study periods, while those for oral antimicrobials decreased in Phase 2, and actual purchase costs increased in Phases 3 and 4. No significant reduction in resistant organisms, length of hospital stay, or mortality was observed. This is the first study on the effects of oral 3GC reduction strategies in patients with cancer. We conclude that even facilities that substantially use antimicrobials can efficiently reduce the use of 3GCs.

Preoperative assessment of dominant occipital sinus in patients with Chiari malformation type I: anatomical variations and implications for preventing potentially life-threatening surgical complications.

OBJECTIVE: The surgical treatment of Chiari malformation type I (CM-I) frequently involves dural incision at the posterior cranial fossa. In cases of persistent patent occipital sinus (OS), the sinus is usually obliterated and divided. However, there are some patients whose OS is prominent and requires crucial modification of the operative planning to avoid potentially life-threatening massive hemorrhage and disturbance of cerebral venous circulation. In the present study, the anatomical variations of the dominant OS in patients with CM-I were analyzed and the authors attempted to develop treatment recommendations for patients with CM-I with dominant OS. METHODS: The study included 213 patients with CM-I who underwent MR venography (MRV) prior to surgical treatment. OS dominance was assessed using 2D time-of-flight MRV or 3D phase-contrast MRV. Particular attention was paid to the pattern of venous outflow channels. The characteristics of the patients with dominant OS and the surgical outcomes were retrospectively reviewed. RESULTS: Dominant OS was identified in 7 patients (3.3%). The age in those with dominant OS was significantly younger than in those without (p = 0.0202). The incidence of concurrent scoliosis in the patients with dominant OS was significantly higher than in those without (p = 0.0366). All the dominant OSs were found to be of the oblique type. Unilateral oblique OS (OOS) with normal ipsilateral transverse sinus (TS) and hypoplastic contralateral TS was found in 2 patients (0.9%). The authors found 1 patient each (0.5%) who had unilateral OOS with hypoplastic ipsilateral TS and normal contralateral TS, unilateral OOS with bilateral hypoplastic TSs, and bilateral OOSs with bilateral normal TSs. Bilateral OOSs with bilateral hypoplastic TSs were found in 2 patients (0.9%). All these patients had syringomyelia. Instead of performing Y-shaped dural incision and duraplasty, surgical procedures were modified depending on the types of the OOSs to preserve their venous drainage routes. Although massive bleeding from the dominant OS during dural incision occurred in 1 patient, none suffered neurological deterioration. The syrinx volume decreased in all but 1 of the patients postoperatively. CONCLUSIONS: Assessment of the venous drainage pattern using MRV is indispensable for safe surgical treatment in patients with CM-I. The surgical procedure should be modified based on the type of dominant OS to minimize the surgical risks.

Intraoperative Cone-Beam Computed Tomography Assessment of Spinal Pedicle Screws Placement Precision Is in Full Agreement with Postoperative Computed Tomography Assessment.

OBJECTIVE: To assess agreement between pedicle screw placement evaluated on postoperative computed tomography (CT) and on intraoperative cone-beam CT (CBCT) and compare procedure characteristics when using first-generation and second-generation robotic C-arm systems in the hybrid operating room. METHODS: All patients who received pedicle screws for spinal fusion at our institution between June 2009 and September 2019 and underwent intraoperative CBCT and postoperative CT were included. The CBCT and CT images were reviewed by 2 surgeons to assess the screw placement using the Gertzbein-Robbins and the Heary classifications. Intermethod agreement of screw placement classifications as well as interrater agreement were assessed using Brennan-Prediger and Gwet agreement coefficients. Procedure characteristics using first-generation and second-generation generation robotic C-arm systems were compared. RESULTS: Fifty-seven patients were treated with 315 pedicle screws at thoracic, lumbar, and sacral levels. No screw had to be repositioned. On CBCT, accurate placement was found for 309 screws (98.1%) using the Gertzbein-Robbins classification and 289 (91.7%) using the Heary classification and on CT, these were 307 (97.4%) and 293 (93.0%), respectively. Intermethod between CBCT and CT and interrater agreements between the 2 raters were almost perfect (>0.90) for all assessment. There were no significant differences in mean radiation dose (P = 0.83) and fluoroscopy time (P = 0.82), but length of surgery using the second-generation system was estimated at 107.7 minutes (95% confidence interval, 31.9-183.5 minutes; P = 0.006) shorter. CONCLUSIONS: Intraoperative CBCT provides accurate assessment of pedicle screw placement and enables intraoperative repositioning of misplaced screws.

[Diagnosis of patients with thoracic outlet syndrome (TOS) using physiological measures of the medial antebrachial cutaneous nerve].

The diagnosis of thoracic outlet syndrome (TOS) remains difficult; therefore, reliable and objective tests are required. We examined the process to diagnose TOS, and assessed the validity of measuring the medial antebrachial cutaneous nerve (MAC), also the ulnar nerve (UN) as a diagnostic tool. Between 2008 and 2011, 86 sides in 73 patients admitted to our hospital for the treatment of TOS were analyzed. In the process for the diagnosis as TOS, the narrow parts of the subclavian artery that was compressed by the anterior scalene muscle were confirmed with a three-dimensional CT angiography. All patients were taken a brachial plexus anesthesiological block to aim at both for diagnosis and treatment of TOS. For the diagnosis of TOS, measurements of latency (LT) and sensory nerve action potential (SNAP) of MAC and UN were analyzed between the TOS side and the non-TOS side and separated into traumatic type or disputed type. In our research, the LT of MAC and UN did not differ much between the TOS side and the non-TOS side; however, the amplitude of SNAP of MAC and UN were lower on the TOS side, especially in traumatic TOS. We concluded that comparison of the amplitude of SNAP of MAC on the injured or non-injured side was comparatively helpful for the diagnosis of TOS.

Fully-Endoscopic Resection of Deep-Seated Pilocytic Astrocytoma Under 5-Aminolevulinic Acid Fluorescence Guidance: A Technical Note.

AIM: To improve the extent and safety of resecting these deep-seated tumors, we report a novel procedure of minimally invasive endoscopic resection of deep-seated pilocytic astrocytomas under the guidance of 5-aminolevulinic acid (5-ALA) fluorescence undescribed until now. CASE DESCRIPTION: A 53-year-old male presented with a gradually progressing mild right hemiparesis. Imaging studies showed a solid tumor with degenerative cystic formation in the left basal ganglia. The tumor was removed endoscopically via right frontal small craniotomy. The tumor was positive for 5-ALA fluorescence and allowed better detection of the dissection margin of the solid tumor from the surrounding brain tissue. The histopathological diagnosis was pilocytic astrocytoma. No recurrence was observed on follow-up magnetic resonance imaging (MRI) 2 years after surgery, and the patient was fully independent after rehabilitation. CONCLUSION: This minimally invasive technique, enhanced by intraoperative fluorescence, might be a safe and feasible alternative to open surgery in the removal of deeply located gliomas.

Effects of infectious disease consultation and antimicrobial stewardship program at a Japanese cancer center: An interrupted time-series analysis.

In cancer patients, appropriate diagnosis and management of infection are frequently challenging owing to subtle or atypical presentation. We investigated the effectiveness of infectious disease (ID) consultations and the Antimicrobial Stewardship Program (ASP) in a Japanese cancer center. This 36-month-period, single-institution, interrupted time series analysis was retrospectively conducted during April 1, 2018-March 31, 2021, to evaluate a two-phase intervention: Phase 1 (notification of antimicrobials by the infection control team) and Phase 2 (establishing an ID consultation service and implementing ASP). Among 32,202 patients hospitalized, 22,096 and 10,106 hospitalizations occurred at baseline and during intervention period, respectively. The Antimicrobial Stewardship Team (AST) provided feedback on specific broad-spectrum antimicrobials in 913 instances (347 appropriate [38%]; 566 inappropriate [62%]), and 440 ID consultations were completed, with a 75% overall acceptance rate for AST suggestions. In Phase 2, monthly carbapenem days of therapy (CAR-DOT) decreased significantly, and narrow-spectrum antibiotic usage increased significantly in both trend and level; monthly DOT of antipseudomonal agents decreased significantly in trend. The results of these analyses of antimicrobial use are consistent with the DOT-based data based on antimicrobial use density (AUD). The total number of inpatient specimens increased significantly; the trend of multidrug-resistant Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus infections decreased, without changes in the incidence of other resistant organisms, all-cause in-hospital mortality, and length of stay. Actual and adjusted CAR purchase costs per patient-day decreased without significant changes in the actual and adjusted purchase cost per patient-day for all intravenous antimicrobials. Combining ID consultation and ASP reduced carbapenem use without negative patient outcomes. Their implementation could facilitate establishment of safe cancer treatment facilities in Japan and improve prognosis in cancer patients.

A case of a common bile duct stone that formed around a fish bone as a nidus after distal gastrectomy with Roux-en-Y reconstruction.

BACKGROUND: The presence of a foreign body in the common bile duct (CBD) is a rare phenomenon. Thus, the route and mechanism of its migration remain difficult to fully clarify, especially for cases that occur after gastrectomy with Roux-en-Y reconstruction. Herein, we present a case of a CBD stone that formed around a fish bone as a nidus subsequent to distal gastrectomy with Roux-en-Y reconstruction. CASE PRESENTATION: A 70-year-old man was admitted to our hospital due to repeated episodes of epigastralgia. He had undergone distal gastrectomy with Roux-en-Y reconstruction for gastric cancer approximately 10 years prior. Blood tests revealed obstructive jaundice, hepatobiliary dysfunction, and inflammation. Multi-plane reconstructed computed tomography (CT) revealed a CBD stone with a needle-shaped calcification density at the center, oriented along the length of the CBD. Surgery was performed using an upper median laparotomy approach. Lithotomy with choledochotomy was performed to remove one fragile bilirubin stone that had formed around a 3-cm, needle-shaped fish bone. A choledochoduodenal fistula was not detected intraoperatively. A review of the imaging of a prior examination revealed that the formation of the CBD stone around the fish bone was observable on a follow-up CT performed approximately 2 years prior. However, no clinical symptoms associated with the migration of the fish bone to the CBD were reported and the fish bone was not detected at that time. CONCLUSION: In this case, transpapillary migration of the fish bone could only be speculated in the absence of an observable fistula, choledochostomy, or any clinical symptoms. Our case is clinically relevant as cholangitis developed after CBD stone formation around the fish bone that acted as a nidus.

Total Spinal Epidural "Blood Patch" Application Through a Racz Catheter in Spontaneous Intracranial Hypotension.

BACKGROUND: Epidural "blood patch" (EBP) is a standard treatment of spontaneous intracranial hypotension (SIH). In recent years, there are some reports of Racz catheter use for EBP performance at upper cervical spine levels. However, the practical use of Racz catheter for single-entry multisite EBP has never been reported until now. CASE DESCRIPTION: We treated a 60-year-old man diagnosed with SIH presenting with cerebrospinal fluid leaks from the cervical to the sacral segments. We discuss the advantages of the single-entry multisite EBP and the convenience of Racz catheter use in such cases. CONCLUSIONS: The Racz catheter can be a convenient means to deliver large-volume EBPs from a single entry point in the treatment of SIH.

Loss of skeletal muscle mass after curative gastrectomy is a poor prognostic factor.

Sarcopenia has been reported to relate to poor prognosis in various malignant cancer types. The present study aimed to clarify the prognostic impact of skeletal muscle mass (SMM) loss after curative gastrectomy in patients with gastric cancer. A total of 119 patients who underwent curative gastrectomy for gastric cancer between 2009 and 2016 were analyzed. The SMM loss at 6 months postoperatively compared with the SMM prior to surgery was calculated using the hospital records. The median loss of SMM was 3.8%. Multivariate logistic regression analysis demonstrated that total gastrectomy was a significant and independent risk factor for SMM loss of ≥5% (odds ratio=2.58; P=0.02). Results from multivariate analysis using stepwise Cox proportional hazards regression indicated that the following factors were significantly associated with shorter overall survival after curative gastrectomy: Age [>70 years; hazard ratio (HR)=2.46, P=0.04], TNM stage (≥2; HR=2.65, P=0.04) and loss of SMM (≥5%; HR=2.57, P=0.03). The present findings suggested that loss of SMM after curative gastrectomy for gastric cancer is an independent predictive factor for poor prognosis.

Laparoscopic low anterior resection for rectal cancer after Whitehead's hemorrhoidectomy: A case report.

A 65-year-old man presented with bloody stool. Colonoscopy revealed a raised tumor in the rectum, above the peritoneal reflection. He underwent endoscopic mucosal resection, but the pathological findings suggested the possibility of residual cancer. We performed laparoscopic low anterior resection using a circular stapling instrument for additional curative surgery. However, we could not insert the shaft of the endoscopic circular stapler from the anus because of anal stenosis due to Whitehead's hemorrhoidectomy the patient had undergone 20 years earlier. Therefore, we planned to use a linear stapler to insert an anvil into the rectum. The cartridge-carrying instrument was inserted from the sigmoidal side, and we performed a side-to-end anastomosis. The patient was discharged without anastomotic leakage or defecation disorder. We present this case because laparoscopic low anterior resection for rectal cancer with anal stenosis has not been previously reported.

Enhancement of cytotoxic effects of gemcitabine by Dclk1 inhibition through suppression of Chk1 phosphorylation in human pancreatic cancer cells.

Although gemcitabine (GEM) is frequently used in the treatment of pancreatic cancer, the effects are limited. To increase the inhibitory effect of GEM, the identification of a molecular target is needed. Recent studies have revealed that doublecortin-like kinase 1 (Dclk1) positively regulates tumor growth, invasion, metastasis, factors related to epithelial-mesenchymal transition (EMT), pluripotency, angiogenesis, and anti-apoptosis in pancreatic cancer cells. Therefore, Dclk1 is a potential therapeutic target for pancreatic cancer. However, the Dclk1-signaling pathway including its substrate proteins remains to be elucidated. To identify the candidate substrate proteins phosphorylated by Dclk1, we performed a cancer-related phosphorylated protein microarray using Dclk1-inhibited MIA Paca2 cells. Expression levels of phosphorylated cdc25A (p-cdc25A) and phosphorylated Chk1 (p-Chk1), belonging to the ATR pathway, were decreased by treatment with Dclk1 inhibitor LRRK2-IN-1 (LRRK), indicating Dclk1 involvement in the ATR pathway. Consistent with this finding, the GEM-induced p-Chk1 expression was significantly decreased by treatment with LRRK. Notably, combined treatment with GEM and LRRK allowed cell cycle progression without arresting at S phase, while individual treatment with GEM induced cell cycle arrest at S phase. In addition, combined treatment with GEM and LRRK increased the number of γ-H2AX-positive cells compared with that upon individual treatments. Moreover, LRRK alone, and combined treatment with GEM and LRRK, induced caspase-3 activation and PARP1 cleavage, in contrast to treatment with GEM alone. Finally, combined treatment with GEM and LRRK significantly reduced cell survival compared to individual treatment with GEM. These results indicate that Dclk1 inhibition in combination with GEM treatment offers a novel approach to treat pancreatic cancer cells.

Autologous preconditioned mesenchymal stem cell sheets improve left ventricular function in a rabbit old myocardial infarction model.

Mesenchymal stem cells (MSCs) constitute one of the most powerful tools for therapeutic angiogenesis in infarcted hearts. However, conventional MSC transplantation approaches result in insufficient therapeutic effects due to poor retention of graft cells in severe ischemic diseases. Cell sheet technology has been developed as a new method to prolong graft cell retention even in ischemic tissue. Recently, we demonstrated that hypoxic pretreatment enhances the therapeutic efficacy of cell sheet implantation in infarcted mouse hearts. In this study, we investigated whether hypoxic pretreatment activates the therapeutic functions of bone marrow-derived MSC (BM-MSC) sheets and improves cardiac function in rabbit infarcted hearts following autologous transplantation. Production of vascular endothelial growth factor (VEGF) was increased in BM-MSC monolayer sheets and it peaked at 48 h under hypoxic culture conditions (2% O2). To examine in vivo effects, preconditioned autologous BM-MSC sheets were implanted into a rabbit old myocardial infarction model. Implantation of preconditioned BM-MSC sheets accelerated angiogenesis in the peri-infarcted area and decreased the infarcted area, leading to improvement of the left ventricular function of the infarcted heart. Importantly, the therapeutic efficacy of the preconditioned BM-MSC sheets was higher than that of standardly cultured sheets. Thus, implantation of autologous preconditioned BM-MSC sheets is a feasible approach for enhancing therapeutic angiogenesis in chronically infarcted hearts.

Increased plasma VEGF levels following ischemic preconditioning are associated with downregulation of miRNA-762 and miR-3072-5p.

Ischemic preconditioning (IPC) has protective effects against ischemia-perfusion injury of organs. In the present study, we investigated the associated mechanisms after performing remote IPC (rIPC) of lower limbs by clamping abdominal aorta in mice. Subsequent experiments showed decreased damage and paralysis of lower limbs following spinal cord injury (SCI). Concomitantly, plasma vascular endothelial growth factor (VEGF) levels were increased 24 h after rIPC compared with those in sham-operated animals. In subsequent microRNA analyses, thirteen microRNAs were downregulated in exosomes 24 h after rIPC. Further studies of femoral CD34-positive bone marrow (BM) cells confirmed downregulation of these seven microRNAs 24 h after rIPC compared with those in sham-operated controls. Subsequent algorithm-based database searches suggested that two of the seven microRNAs bind to the 3' UTR of VEGF mRNA, and following transfection into CD34-positive BM cells, anti-miR-762, and anti-miR-3072-5p inhibitors led to increased VEGF concentrations. The present data suggest that rIPC transiently increases plasma VEGF levels by downregulating miR-762 and miR-3072-5p in CD34-positive BM cells, leading to protection against organ ischemia.

Influence of aging on the quantity and quality of human cardiac stem cells.

Advanced age affects various tissue-specific stem cells and decreases their regenerative ability. We therefore examined whether aging affected the quantity and quality of cardiac stem cells using cells obtained from 26 patients of various ages (from 2 to 83 years old). We collected fresh right atria and cultured cardiosphere-derived cells (CDCs), which are a type of cardiac stem cell. Then we investigated growth rate, senescence, DNA damage, and the growth factor production of CDCs. All samples yielded a sufficient number of CDCs for experiments and the cellular growth rate was not obviously associated with age. The expression of senescence-associated b-galactosidase and the DNA damage marker, gH2AX, showed a slightly higher trend in CDCs from older patients (≥ 65 years). The expression of VEGF, HGF, IGF-1, SDF-1, and TGF-b varied among samples, and the expression of these beneficial factors did not decrease with age. An in vitro angiogenesis assay also showed that the angiogenic potency of CDCs was not impaired, even in those from older patients. Our data suggest that the impact of age on the quantity and quality of CDCs is quite limited. These findings have important clinical implications for autologous stem cell transplantation in elderly patients.

Single-incision laparoscopic splenectomy and splenic autotransplantation for an enlarged wandering spleen with torsion.

A wandering spleen is a rare condition in which the spleen is not located in the left upper quadrant, but instead is found in the lower abdomen or in the pelvic region because of the laxity of the peritoneal attachments. The unusually long pedicle is susceptible to twisting, which can lead to ischemia, and eventually to necrosis. We herein report a case of an enlarged wandering spleen with torsion, successfully treated by single-incision laparoscopic splenectomy and autotransplantation. The transplanted splenic tissues could be identified on a spleen scintigram obtained 3 months after the surgery. Howell-Jolly bodies were not observed in blood specimens. This procedure is able to prevent an overwhelming postsplenectomy infection, and leads to satisfactory cosmetic results.

Measurement of exciton diffusion in a well-defined donor/acceptor heterojunction based on a conjugated polymer and cross-linked fullerene derivative.

We designed a well-defined donor/acceptor heterojunction for measuring exciton diffusion lengths in conjugated polymers. To obtain an insoluble electron acceptor layer, a new cross-linkable fullerene derivative (bis-PCBVB) was synthesized by functionalizing [6,6]-diphenyl-C62-bis(butyric acid methyl ester) (bis-PCBM) with two styryl groups. The spin-coated bis-PCBVB film was cross-linked in situ by heating at 170 °C for 60 min. Surface characterizations by UV-visible absorption, atomic force microscopy, and photoelectron yield spectroscopy revealed that a smooth and solvent-resistant film (p-PCBVB) was obtained. In bilayer films with a donor conjugated polymer, poly[2,7-(9,9-didodecylfluorene)-alt-5,5-(4',7'-bis(2-thienyl)-2',1',3'-benzothiadiazole)] (PF12TBT), spin-coated on top of the p-PCBVB acceptor layer, the photoluminescence (PL) of the PF12TBT was effectively quenched. This is because the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of the p-PCBVB film are nearly the same as those of the parent bis-PCBM spin-coated film. On the basis of the PL quenching results, the exciton diffusion length and exciton diffusion coefficient in the PF12TBT were evaluated to be 11 nm and 9.8 × 10(-4) cm(2) s(-1), respectively.