Varying clinical relevance of sarcopenia and myosteatosis according to age among patients with postoperative colorectal cancer.

OBJECTIVES: The present retrospective study reviewed the association among sarcopenia, myosteatosis, and overall survival (OS) in patients with postoperative colorectal cancer (CRC) with regard to age. DESIGN: A retrospective study was conducted with a five-year follow-up. SETTING: Data from all patients with CRC, who underwent surgery between February 2005 and April 2014, were reviewed. PARTICIPANTS: Data from 1053 patients (622 male [59.1%], 431 female [40.9%]; mean [± SD] age, 62.8 ± 11.8 years) were analyzed. MEASUREMENTS: Patients were divided into three groups according to age: ≤50, 51-74, and ≥75 years. Data, including perioperative parameters, and the presence of sarcopenia and myosteatosis according to skeletal muscle index (SMI) and skeletal muscle radiodensity (SMD), respectively, were collected. Sarcopenia was evaluated using CT by calculating the SMI at the L3 level by dividing the area of the skeletal muscle by height squared (cm2/m2). SMD was also calculated using CT at the L3 level, but by evaluating fat attenuation according to Hounsfield units (HU). RESULTS: Patient allocation according to age group was as follows: ≤50 years, n = 147 (14.0%); 51-74 years, n = 742 (70.5%); and ≥75 years, n = 164 (15.5%). The presence of sarcopenia and myosteatosis were statistically significant with increasing age (P = 0.004 and P < 0.001, respectively). The 51-74 years age group exhibited a significant association in OS for myosteatosis (P < 0.001) while the ≥75 years group was significantly associated with sarcopenia (P = 0.04) with regard to OS. Multivariable analysis also revealed a statistically significant association between myosteatosis in the 51-74 years age group (P = 0.033) and sarcopenia in the ≥75 years age group (P = 0.005) even when adjusted for recurrence status. CONCLUSION: Different age groups exhibited significantly variable skeletal muscle indices. Although an abundance of irrefutable results demonstrated a correlation between CT-defined sarcopenia, myosteatosis, and clinical prognosis, data regarding age-dependent correlations are scarce. Results of this study demonstrated that sarcopenia and myosteatosis did not influence the prognosis of young patients with postoperative CRC (≤50 years of age), inferring the existence of significantly different skeletal muscle-related parameters according to age. Patients over 75 years of age showed significant association with sarcopenia while those in the 51-74 age group displayed significant link to myosteatosis. Clinicians should consider the impact of sarcopenia and myosteatosis on patient prognosis and should also be aware that the effect may differ according to patient age.

Association between cortical thickness and cognitive ability in very preterm school-age children.

Very preterm children, born before 32 weeks of gestation, are at risk for impaired cognitive function, mediated by several risk factors. Cognitive impairment can be measured by various neurodevelopmental assessments and is closely associated with structural alterations of brain morphometry, such as cortical thickness. However, the association between structural alterations and high-order cognitive function remains unclear. This study aimed to investigate the neurodevelopmental associations between brain structural changes and cognitive abilities in very preterm and full-term children. Cortical thickness was assessed in 37 very preterm and 24 full-term children aged 6 years. Cortical thickness analysis of structural T1-weighted images was performed using Advanced Normalization Tools. Associations between cortical thickness and the Wechsler Intelligence Scale for Children were evaluated by regression analysis based on ordinary least square estimation. Compared with full-term children, very preterm children showed significant differences in cortical thickness, variously associated with cognitive abilities in several brain regions. Perceptual reasoning indices were broadly correlated with cortical thickness in very preterm and full-term children. These findings provide important insights into neurodevelopment and its association with cortical thickness, which may serve as a biomarker in predictive models for neurodevelopmental diagnosis of high-order cognitive function.

Is cytoreductive surgery and hyperthermic intraperitoneal chemotherapy still beneficial in patients diagnosed with colorectal peritoneal metastasis who underwent palliative chemotherapy?

BACKGROUND: With a 5-year overall survival of less than 5%, colorectal peritoneal metastasis (CPM) patients are often managed with palliative chemotherapy (CTx). In the past few decades, cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has been introduced as a possible curative treatment for highly selective CPM patients. We share our experience of CRS and HIPEC given the unique characteristics of the medical system and the benefit of CRS and HIPEC in palliative setting. METHODS: From April 2017 to October 2021, CPM patients who underwent CRS and HIPEC were analyzed. Patients were allocated into perioperative and palliative CTx arm based on the duration between initial diagnosis of CPM to undergoing CRS and HIPEC of 6 months. Data including perioperative parameters, postoperative outcomes, and survival were analyzed with a median follow-up of 28.5 months. RESULTS: Twenty-six CPM patients underwent CRS and HIPEC. Mean time from diagnosis of CPM to CRS and HIPEC was 5.5 months with 14 patients in the perioperative arm and 12 patients in the palliative arm. Perioperative group showed a longer RFS of 13.5 months compared to 8 months in the palliative group. Median overall survival of palliative group was 41.50 months, and 18 patients among all groups are alive at the time of this report. CONCLUSION: CRS and HIPEC could be a treatment option for a carefully selected CPM patients performed by experienced surgeons. Overall survival of 41.50 months in palliative group compared to 16.8 months from conventional systemic CTx supports CRS and HIPEC even in palliative patients.

Circular RNA circSMAD4 regulates cardiac fibrosis by targeting miR-671-5p and FGFR2 in cardiac fibroblasts.

Heart failure is a leading cause of death and is often accompanied by activation of quiescent cardiac myofibroblasts, which results in cardiac fibrosis. In this study, we aimed to identify novel circular RNAs that regulate cardiac fibrosis. We applied transverse aortic constriction (TAC) for 1, 4, and 8 weeks in mice. RNA sequencing datasets were obtained from cardiac fibroblasts isolated by use of a Langendorff apparatus and then further processed by use of selection criteria such as differential expression and conservation in species. CircSMAD4 was upregulated by TAC in mice or by transforming growth factor (TGF)-ß1 in primarily cultured human cardiac fibroblasts. Delivery of si-circSMAD4 attenuated myofibroblast activation and cardiac fibrosis in mice treated with isoproterenol (ISP). si-circSmad4 significantly reduced cardiac fibrosis and remodeling at 8 weeks. Mechanistically, circSMAD4 acted as a sponge against the microRNA miR-671-5p in a sequence-specific manner. miR-671-5p was downregulated during myofibroblast activation and its mimic form attenuated cardiac fibrosis. miR-671-5p mimic destabilized fibroblast growth factor receptor 2 (FGFR2) mRNA in a sequence-specific manner and interfered with the fibrotic action of FGFR2. The circSMAD4-miR-671-5p-FGFR2 pathway is involved in the differentiation of cardiac myofibroblasts and thereby the development of cardiac fibrosis.

Genetic variants of MUC4 are associated with susceptibility to and mortality of colorectal cancer and exhibit synergistic effects with LDL-C levels.

As a disease with high mortality and prevalence rates worldwide, colorectal cancer (CRC) has been thoroughly investigated. Mucins are involved in the induction of CRC and the regulation of intestinal homeostasis but a member of the mucin gene family MUC4 has a controversial role in CRC. MUC4 has been associated with either decreased susceptibility to or a worse prognosis of CRC. In our study, the multifunctional aspects of MUC4 were elucidated by genetic polymorphism analysis in a case-control study of 420 controls and 464 CRC patients. MUC4 rs1104760 A>G polymorphism had a protective effect on CRC risk (AG, AOR = 0.537; GG, AOR = 0.297; dominant model, AOR = 0.493; recessive model, AOR = 0.382) and MUC4 rs2688513 A>G was associated with an increased mortality rate of CRC (5 years, GG, adjusted HR = 6.496; recessive model, adjusted HR = 5.848). In addition, MUC4 rs1104760 A>G showed a high probability of being a potential biomarker for CRC patients with low-density lipoprotein cholesterol (LDL-C) in the risk range while showing a significant synergistic effect with the LDL-C level. This is the first study to indicate a significant association between MUC4 genetic polymorphisms and CRC prevalence, suggesting a functional genetic variant with the LDL-C level, for CRC prevention.

Abnormal Vaginal Flora in Cervical Incompetence Patients - the Impact of Escherichia coli.

The purpose of this study was to investigate the prevalence of abnormal vaginal colonization in women with cervical incompetence and to analyze its impact on obstetric and neonatal outcomes and placental inflammation. We included 138 pregnant women diagnosed with cervical incompetence and delivered in our hospital. Patients with major fetal anomaly or multifetal pregnancy were excluded. Upper vaginal culture was performed on the day of admission. A total of 60.9% (84/138) of cervical incompetence patients had abnormal bacterial colonization, and Escherichia coli (E. coli) was the most common colonized pathogen (33.3%, 46/138). The positive vaginal E. coli group had a higher rate of prior preterm birth (p = 0.021) and an earlier gestational age at which cervical incompetence was diagnosed (p < 0.01) than the negative group. The positive vaginal E. coli group had higher rates of clinical chorioamnionitis (p = 0.008) and subchorionic microabscess of the placenta (p = 0.012). Importantly, the positive vaginal E. coli group had significantly higher rates of proven early-onset neonatal sepsis (EONS) (p = 0.046), necrotizing enterocolitis (NEC) (p = 0.001), and neonatal mortality (p = 0.023). After adjusting for confounding variables, the positive vaginal E. coli group had significantly higher risk for proven EONS (OR: 3.853, 95% CI: 1.056-14.055) and NEC (OR: 12.410, 95% CI: 1.290-119.351). In conclusion, E. coli was the most common vaginal microorganism isolated from patients with cervical incompetence. Maternal vaginal E. coli colonization was associated with adverse neonatal outcomes including proven EONS and NEC and was characterized by a higher rate of placental subchorionic microabscess.

Clinical efficacy of a novel method of fertility-preserving adenomyomectomy in infertile women with diffuse adenomyosis.

Beneficial and detrimental effect of surgical adenomyomectomy is still controversial in infertile women with severely diffuse adenomyosis. The primary objective of this study was to assess whether a novel method of fertility-preserving adenomyomectomy could improve pregnancy rates. The secondary objective was to evaluate whether it could improve dysmenorrhea and menorrhagia symptoms in infertile patients with severe adenomyosis. A prospective clinical trial was conducted between December 2007 and September 2016. Fifty women with infertility due to adenomyosis were enrolled in this study after clinical assessments by infertility experts. A novel method of fertility-preserving adenomyomectomy was performed on 45 of 50 patients. The procedure included T- or transverse H-incision of the uterine serosa followed by preparation of the serosal flap, excision of the adenomyotic tissue using argon laser under ultrasonographic monitoring, and a novel technique of suturing between the residual myometrium and serosal flap. After the adenomyomectomy, the changes in the amount of menstrual blood, relief of dysmenorrhea, pregnancy outcomes, clinical characteristics, and surgical features were recorded and analyzed. All patients obtained dysmenorrhea relief 6 months postoperatively (numeric rating scale [NRS]; 7.28 ±â€…2.30 vs 1.56 ±â€…1.30, P < .001). The amount of menstrual blood decreased significantly (140.44 ±â€…91.68 vs 66.33 ±â€…65.85 mL, P < .05). Of the 33 patients who attempted pregnancy postoperatively, 18 (54.5%) conceived either by natural means, in vitro fertilization and embryo transfer (IVF-ET), or thawing embryo transfer. Miscarriage occurred in 8 patients, while 10 (30.3%) had viable pregnancies. This novel method of adenomyomectomy resulted in improved pregnancy rates, as well as relief of dysmenorrhea and menorrhagia. This operation is effective in preserving fertility potential in infertile women with diffuse adenomyosis.

Growing threat of extended-spectrum ß-lactamase-producing Enterobacteriaceae colonisation in high-risk pregnancies: A cross-sectional study.

OBJECTIVE: To investigate the epidemiological changes in extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-E) vaginal colonisation in pregnant women deemed at high risk, and to identify independent risk factors. Further, the differences in perinatal outcomes according to maternal ESBL-E vaginal colonisation were analysed. DESIGN: Cross-sectional study. SETTING: Republic of Korea. POPULATION: A cohort of 1460 women admitted to our high-risk pregnancy unit between 14+0 and 36+6  weeks of gestation. METHODS: The trend of changes in the association of ESBL-E vaginal colonisation from January 2010 to December 2020 was analysed. The main outcomes were analysed over the study period and ESBL-E vaginal colonisation. MAIN OUTCOME MEASURES: Rate of ESBL-E vaginal colonisation, risk factors for ESBL-E vaginal colonisation and perinatal outcomes. RESULTS: The ESBL-E vaginal colonisation rate has tended to increase over the past 11 years, which was attributed to a significantly higher proportion of ESBL-producing Escherichia coli. Cerclage (RR 3.7, 95% CI 2.19-6.40) and prior antibiotic treatment (RR 4.0, 95% CI 2.44-6.54) were found as independent risk factors for ESBL-E vaginal colonisation. Earlier gestational age at delivery and higher proven early-onset neonatal sepsis (EONS) rate were observed in the ESBL-E-positive group. CONCLUSIONS: The ESBL-E vaginal colonisation rate in pregnant patients at high risk has increased over the past decade, and the independent risk factors for colonisation are cerclage and prior antibiotic treatment. Additionally, maternal ESBL-E vaginal colonisation is associated with higher rates of proven EONS.

Altered functional connectivity in children born very preterm at school age.

Children born very preterm are at significant risk of neurodevelopmental impairment. This study sought to identify differences in cognitive function in children born very preterm compared to term-born controls and investigate alteration in white matter microstructure and functional connectivity (FC) based on tract-based spatial statistics (TBSS) and resting-state functional MRI, respectively. At 6 years of age, 36 children born very preterm (< 32 weeks' gestation) without major neurological disabilities and 26 term-born controls were tested using the Wechsler Intelligence Scale for Children, 4th edition, and Child Behavior Checklist. Whole-brain deterministic tractography and FC measurements were performed in both groups. The very preterm group had significantly lower intelligence scores than the term-born controls. The TBSS revealed no significant differences between the two groups, whereas FC was significantly increased between the frontoparietal network and the language network and was significantly decreased between the right salience network nodes in the very preterm group. The altered FC patterns between specific regions of the higher-order networks may reflect underlying deficits in the functional network architecture associated with cognitive function. Further studies are needed to demonstrate a direct connection between FC in these regions and cognitive function.

Prognostic significance of three endothelial nitric oxide synthase (eNOS) polymorphisms and metabolic syndrome (MetS) in patients with colorectal cancer.

BACKGROUND: Polymorphisms of endothelial nitric oxide synthases (eNOS) have been associated with cancer susceptibility. Also, metabolic syndrome is associated with cancer malignancy. However, the effect of eNOS polymorphisms and metabolic syndrome on colorectal cancer (CRC) prognosis remains unclear. OBJECTIVE: To investigated whether three genetic polymorphisms (- 786 T > C rs2070744, 4a4b rs869109213, and 894G > T rs1799983) in the eNOS and metabolic syndrome (MetS) were associated with CRC patient survival. METHODS: We genotyped three polymorphisms of eNOS (- 786 T > C, 4a4b, and 894G > T) in 312 CRC cases from the Korean population by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. RESULTS: Although the three eNOS polymorphisms were not causative of MetS, the TT genotype of the 894G > T polymorphism was associated with a worse survival rate compared with the GG genotype in the CRC group with MetS than in the CRC group without MetS (5-years survival; adjusted HR = 54.777; 95% CI 5.073-591.487 and RFS; adjusted HR = 14.909; 95% CI 1.571-141.528). CONCLUSIONS: The eNOS polymorphisms were not associated with metabolic syndrome prevalence in CRC patients. However, our findings suggest that the eNOS 894G > T polymorphism with MetS was associated with poor clinical outcomes.

The role of prosodic and visual information in disambiguating wh-indeterminates: The case of Korean three-year-olds.

In Korean language, questions containing ambiguous wh-words may be interpreted as either wh-questions or yes-no questions. This study investigated 43 Korean three-year-olds' ability to disambiguate eight indeterminate questions using prosodic and visual cues. The intonation of each question provided a cue as to whether it should be interpreted as a wh-question or a yes-no question. The questions were presented alongside picture stimuli, which acted as either a matched (presentation of corresponding auditory-visual stimuli) or a mismatched contextual cue (presentation conflicting auditory-visual stimuli). Like adults, the children preferred to comprehend questions involving ambiguous wh-words as wh-questions, rather than yes-no questions. In addition, children were as effective as adults in disambiguating indeterminate questions using prosodic cues regardless of the visual cue. However, when confronted with conflicting auditory-visual stimuli (mismatched), the quality of children's responses was less accurate than adults' responses.

A comparative study between open versus laparoscopic Hartmann reversal: A single-center experience and analysis.

ABSTRACT: As one of the most challenging procedures in colorectal surgery, Hartmann reversal (HR) carries a burden of morbidity and mortality. We report our experience and compare open and laparoscopic HR.Between December 2012 and January 2020, 30 patients who underwent Hartmann reversal were reviewed. All patients either received laparoscopic or open reversal.Of the 87 patients who underwent Hartmann operation (HO), 30 patients received HR (Laparoscopic Hartmann Reversal, [LHR], n = 20; Open Hartmann Reversal, Open Hartmann Reversal [OHR], n = 10). There were 15 males and 15 female patients. The mean operation time was 223.8 minutes (range 115-350 minutes) with mean blood loss of 252.5 mL (range 0-700 mL). There was no conversion from LHR to OHR, and there was no ileostomy formation. Mean time to flatus was 5.0 days (range 2-13 days). There were 15 early postoperative complications and 5 late postoperative complications, but only 1 case of grade 3A. No anastomosis leakage was reported.HR is an operation that can be performed safely in well-selected patients. Minimally invasive techniques, such as LHR, is an attractive option resulting in shorter operation time, less blood loss, less pain, and shorter hospital stay.

Colonic Perforation After Treatment With Nivolumab in Esophageal Cancer: A Case Report.

With the advent of checkpoint inhibitors, it has opened up opportunities for numerous cancer patients. However, as is the case with every treatment, complications need to be weighed. Gastrointestinal adverse effects, such as diarrhea and colitis are well-known complications for checkpoint inhibitors. In severe cases, colitis-induced colonic perforation may occur with an estimation of 1.0% to 1.5% in anti-CTLA-4 antibodies. However, only a handful of cases of such devastating complications have been reported in anti-PD-1 antibodies such as pembrolizumab and nivolumab. We here report a case of intestinal perforation in a patient treated with nivolumab.

Robotic limited local resection of duodenal juxta-ampullary neoplasms.

BACKGROUND: The unique and complex anatomical location of duodenal juxta-ampullary neoplasms complicates selection of the appropriate surgical strategy. For benign or borderline tumours, surgical local resection can be an appropriate treatment option, and robotic surgical systems can help perform minimally invasive local resection of these lesions. METHODS: Between December 2014 and December 2019, 10 patients who underwent robotic local resections for duodenal juxta-ampullary tumours were reviewed. RESULTS: All patients successfully underwent robotic local resection of the duodenum, preserving the ampulla of Vater without conversion. The mean tumour size was 2.2 cm. Final pathology consisted of gastrointestinal stromal tumour, neuroendocrine tumour, low grade and high grade dysplasia, ectopic pancreas, and well-differentiated adenocarcinoma (T1a). There were no postoperative complications or recurrences. CONCLUSION: With accurate preoperative diagnosis and careful selection of patients, local resection of the duodenum for juxta-ampullary benign or borderline tumours using robotic surgical system is an attractive treatment option.

Easily Applicable Single-incision Laparoscopic Appendectomy Using Straightforward Instrumental Alignment and Conventional Laparoscopic Instruments.

BACKGROUND: Laparoscopic appendectomy is one of the most frequently performed operations. As such, single-incision laparoscopic appendectomy (SILA) is indicated as a feasible and safe procedure comparable to conventional laparoscopic appendectomy (CLA). However, novice surgeons face challenges in performing SILA, because the role of the surgeon's hands is reversed. We introduce an easily applicable technique of SILA by adapting the alignment of CLA. METHODS: A series of 61 consecutive patients underwent SILA between January 2019 and December 2019 by 4 surgeons at Bundang CHA Medical Center. Acute appendicitis was diagnosed preoperatively by abdomino-pelvis computed tomography or ultrasonography. During the operation, a 3-channel Glove port was used with conventional laparoscopic instruments. RESULTS: The study participants consisted of 32 males and 29 females, with a mean age of 26.8 years (range, 4 to 66 y). The mean body mass index was 20.79 kg/m2 (range, 11.89 to 27.04 kg/m2). The mean operation time was 37.5±17.0 minutes. There was only 1 case of conversion with 1 additional port. Eight patients (13.1%) experienced postoperative complications defined by Dindo-Clavien-Strasberg classification: grade 1 wound complication in 7 patients and grade 2 postoperative bowel obstruction in 1 patient. The mean postoperative hospital stay was 2.5±1.3 days. CONCLUSION: Alignment of the instruments during CLA was successfully implemented into a SILA. Our new, easily applicable SILA technique will decrease the learning curve for novice surgeons in performing single-incision laparoscopic surgery.

miR-27a-3p Targets ATF3 to Reduce Calcium Deposition in Vascular Smooth Muscle Cells.

Vascular calcification, the ectopic deposition of calcium in blood vessels, develops in association with various metabolic diseases and atherosclerosis and is an independent predictor of morbidity and mortality associated with these diseases. Herein, we report that reduction of microRNA-27a-3p (miR-27a-3p) causes an increase in activating transcription factor 3 (ATF3), a novel osteogenic transcription factor, in vascular smooth muscle cells. Both microRNA (miRNA) and mRNA microarrays were performed with rat vascular smooth muscle cells, and reciprocally regulated pairs of miRNA and mRNA were selected after bioinformatics analysis. Inorganic phosphate significantly reduced the expression of miR-27a-3p in A10 cells. The transcript level was also reduced in vitamin D3-administered mouse aortas. miR-27a-3p mimic reduced calcium deposition, whereas miR-27a-3p inhibitor increased it. The Atf3 mRNA level was upregulated in a cellular vascular calcification model, and miR-27a-3p reduced the Atf3 mRNA and protein levels. Transfection with Atf3 could recover the miR-27a-3p-induced reduction of calcium deposition. Our results suggest that reduction of miR-27a-3p may contribute to the development of vascular calcification by de-repression of ATF3.

Histologic features of sublingual gland herniation through the mylohyoid muscle.

OBJECTIVES/HYPOTHESIS: The purpose of this study was to document histologic features of the herniated sublingual gland (SLG) and investigate the histologic correlation between herniated SLG and plunging ranula. METHODS: One hundred half-heads from 50 adult cadavers (21 females and 29 males) were included in this study. The presence of SLG herniation and the histologic features SLG were analyzed. The histologic features were analyzed according to the part: intraoral, junctional, and herniated parts. Hematoxylin and eosin (H&E), periodic acid Schiff reaction (PAS), and Alcian Blue (pH 2.5) staining were performed. RESULTS: SLG herniation was found in 42 of 100 half-heads. Non-herniated SLG and the intraoral part of the herniated SLG were mainly composed of mucous acini and a few mixed acini. Junctional and herniated parts were mainly composed of serous acini and showed fatty change. PAS and Alcian blue staining showed that both acidic and neutral mucinous acini of junctional and herniated parts were decreased. However, there was no pseudo-epithelium at any site of herniation. CONCLUSIONS: The histologic features of herniated SLG are different according the portions. The herniated part showed fatty degeneration and the remaining acini were mainly serous. We cannot confer any correlation between plunging ranula and the herniated part of SLGs.

Central line-associated bloodstream infections in neonates.

Newborn infants, including premature infants, are high-risk patients susceptible to various microorganisms. Catheter-related bloodstream infections are the most common type of nosocomial infections in this population. Regular education and training of medical staffs are most important as a preventive strategy for central line-associated bloodstream infections (CLABSIs). Bundle approaches and the use of checklists during the insertion and maintenance of central catheters are effective measures to reduce the incidence of CLABSIs. Chlorhexidine, commonly used as a skin disinfectant before catheter insertion and dressing replacement, is not approved for infants <2 months of age, but is usually used in many neonatal intensive care units due to the lack of alternatives. Chlorhexidine-impregnated dressing and bathing, recommended for adults, cannot be applied to newborns. Appropriate replacement intervals for dressing and administration sets are similar to those recommended for adults. Umbilical catheters should not be used longer than 5 days for the umbilical arterial catheter and 14 days for the umbilical venous catheter. It is most important to regularly educate, train and give feedback to the medical staffs about the various preventive measures required at each stage from before insertion to removal of the catheter. Continuous efforts are needed to develop effective and safe infection control strategies for neonates and young infants.

Knockdown of PRKAR2B Results in the Failure of Oocyte Maturation.

BACKGROUND/AIMS: Cyclic adenosine monophosphate (cAMP)-dependent type 2 regulatory subunit beta (Prkar2b) is a regulatory isoform of cAMP-dependent protein kinase (PKA), which is the primary target for cAMP actions. In oocytes, PKA and the pentose phosphate pathway (PPP) have important roles during the germinal vesicle (GV) stage arrest of development. Although the roles of the PKA signal pathway have been studied in the development of oocyte, there has been no report on the function of PRKAR2B, a key regulator of PKA. METHODS: Using reverse transcription polymerase chain reaction (RT-PCR), quantitative real-time PCR (qRT-PCR), immunohistochemistry, and immunofluorescence, we determined the relative expression of Prkar2b in various tissues, including ovarian follicles, during oocyte maturation. Prkar2b-interfering RNA (RNAi) microinjection was conducted to confirm the effect of Prkar2b knockdown, and immunofluorescence, qRT-PCR, and time-lapse video microscopy were used to analyze Prkar2b-deficient oocytes. RESULTS: Prkar2b is strongly expressed in the ovarian tissues, particularly in the growing follicle. During oocyte maturation, the highest expression of Prkar2b was during metaphase I (MI), with a significant decrease at metaphase II (MII). RNAi-mediated Prkar2b suppression resulted in MI-stage arrest during oocyte development, and these oocytes exhibited abnormal spindle formation and chromosome aggregation. Expression of other members of the PKA family (except for Prkaca) were decreased, and the majority of the PPP factors were also reduced in Prkar2b-deficient oocytes. CONCLUSION: These results suggest that Prkar2b is closely involved in the maturation of oocytes by controlling spindle formation and PPP-mediated metabolism.

Intravoxel incoherent motion diffusion-weighted imaging for monitoring chemotherapeutic efficacy in gastric cancer.

AIM: To assess intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) for monitoring early efficacy of chemotherapy in a human gastric cancer mouse model. METHODS: IVIM-DWI was performed with 12 b-values (0-800 s/mm(2)) in 25 human gastric cancer-bearing nude mice at baseline (day 0), and then they were randomly divided into control and 1-, 3-, 5- and 7-d treatment groups (n = 5 per group). The control group underwent longitudinal MRI scans at days 1, 3, 5 and 7, and the treatment groups underwent subsequent MRI scans after a specified 5-fluorouracil/calcium folinate treatment. Together with tumor volumes (TV), the apparent diffusion coefficient (ADC) and IVIM parameters [true water molecular diffusion coefficient (D), perfusion fraction (f) and pseudo-related diffusion coefficient (D(*))] were measured. The differences in those parameters from baseline to each measurement (ΔTV%, ΔADC%, ΔD%, Δf% and ΔD(*)%) were calculated. After image acquisition, tumor necrosis, microvessel density (MVD) and cellular apoptosis were evaluated by hematoxylin-eosin (HE), CD31 and terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL) staining respectively, to confirm the imaging findings. Mann-Whitney test and Spearman's correlation coefficient analysis were performed. RESULTS: The observed relative volume increase (ΔTV%) in the treatment group were significantly smaller than those in the control group at day 5 (ΔTVtreatment% = 19.63% ± 3.01% and ΔTVcontrol% = 83.60% ± 14.87%, P = 0.008) and day 7 (ΔTVtreatment% = 29.07% ± 10.01% and ΔTVcontrol% = 177.06% ± 63.00%, P = 0.008). The difference in ΔTV% between the treatment and the control groups was not significant at days 1 and 3 after a short duration of treatment. Increases in ADC in the treatment group (ΔADC%treatment, median, 30.10% ± 18.32%, 36.11% ± 21.82%, 45.22% ± 24.36%) were significantly higher compared with the control group (ΔADC%control, median, 4.98% ± 3.39%, 6.26% ± 3.08%, 9.24% ± 6.33%) at days 3, 5 and 7 (P = 0.008, P = 0.016, P = 0.008, respectively). Increases in D in the treatment group (ΔD%treatment, median 17.12% ± 8.20%, 24.16% ± 16.87%, 38.54% ± 19.36%) were higher than those in the control group (ΔD%control, median -0.13% ± 4.23%, 5.89% ± 4.56%, 5.54% ± 4.44%) at days 1, 3, and 5 (P = 0.032, P = 0.008, P = 0.016, respectively). Relative changes in f were significantly lower in the treatment group compared with the control group at days 1, 3, 5 and 7 follow-up (median, -34.13% ± 16.61% vs 1.68% ± 3.40%, P = 0.016; -50.64% ± 6.82% vs 3.01% ± 6.50%, P = 0.008; -49.93% ± 6.05% vs 0.97% ± 4.38%, P = 0.008, and -46.22% ± 7.75% vs 8.14% ± 6.75%, P = 0.008, respectively). D* in the treatment group decreased significantly compared to those in the control group at all time points (median, -32.10% ± 12.22% vs 1.85% ± 5.54%, P = 0.008; -44.14% ± 14.83% vs 2.29% ± 10.38%, P = 0.008; -59.06% ± 19.10% vs 3.86% ± 5.10%, P = 0.008 and -47.20% ± 20.48% vs 7.13% ± 9.88%, P = 0.016, respectively). Furthermore, histopathologic findings showed positive correlations with ADC and D and tumor necrosis (r s = 0.720, P < 0.001; r s = 0.522, P = 0.007, respectively). The cellular apoptosis of the tumor also showed positive correlations with ADC and D (r s = 0.626, P = 0.001; r s = 0.542, P = 0.005, respectively). Perfusion-related parameters (f and D(*)) were positively correlated to MVD (r s = 0.618, P = 0.001; r s = 0.538, P = 0.006, respectively), and negatively correlated to cellular apoptosis of the tumor (r s = -0.550, P = 0.004; r s = -0.692, P < 0.001, respectively). CONCLUSION: IVIM-DWI is potentially useful for predicting the early efficacy of chemotherapy in a human gastric cancer mouse model.