CDKN2B deletion is essential for pancreatic cancer development instead of unmeaningful co-deletion due to juxtaposition to CDKN2A

Pancreatic cancer is among the deadliest malignancies; however, the genetic events that lead to pancreatic carcinogenesis in adults remain unclear. In vivo models in which these genetic alterations occur in adult animals may more accurately reflect the features of human cancer. In this study, we demonstrate that inactivation of Cdkn2b (p15ink4b) is necessary for induction of pancreatic cancer by oncogenic KRAS^G12D expression and inactivation of Tp53 and Cdkn2a in adult mouse pancreatic ductal cells (P60 or older). KRAS^G12D overexpression in these cells activated transforming growth factor-β signaling and expression of CDKN2B, which, along with CDKN2A, led to cellular senescence and protected cells from KRAS-mediated transformation via inhibition of retinoblastoma phosphorylation. These results show a critical role of CDKN2B inactivation in pancreatic carcinogenesis, and provide a useful adult animal model by genetic engineering via lentiviral delivery.

Associations between benign cutaneous nevi and risk of Type 2 diabetes mellitus in men and women: results from two prospective cohort studies

AIM

To examine the association of cutaneous nevi with Type 2 diabetes risk.

METHODS

We prospectivly examined the associations between nevus count and risk of Type 2 diabetes among 26 240 men (1988-2010) from the Health Professionals Follow-up Study and 67 050 women (1986-2010) from the Nurses' Health Study. Information on the numbers of cutaneous nevi on arms at baseline and incident cases of Type 2 diabetes was collected using validated questionnaires.

RESULTS

During 1 879 287 person-years of follow-up, we documented 9040 incident cases of Type 2 diabetes. After adjustment for age, BMI and other diabetes risk factors, greater number of nevi was associated with higher risk of Type 2 diabetes. Multivariable-adjusted hazard ratios for <1, 1-5, 6-14 and ≥15 nevi were 1.00 (reference), 1.02 (95% CI 0.93, 1.13), 1.08 (95% CI 0.88, 1.34) and 1.57 (95% CI 1.15, 2.15), respectively, for men (P for linear trend = 0.01), and 1.00 (reference), 1.07 (95% CI 1.02, 1.13), 0.98 (95% CI 0.87, 1.10), and 1.25 (1.01, 1.54), respectively, for women (P for linear trend = 0.05). This positive association remained consistent across subgroups stratified by age, BMI, multivitamin use, smoking status, alcohol, physical activity, history of hypercholesterolaemia, family history of diabetes, history of hypertension and menopausal status (in women).

CONCLUSIONS

Cutaneous nevus count may represent a novel marker for development of Type 2 diabetes, suggesting a possible unique melanocytic nevus-related mechanism in the pathogenesis of Type 2 diabetes. Further studies are warranted to confirm the findings and to investigate the underlying mechanisms.

Factors leading to rehospitalization for tracheostomized and ventilator-dependent infants through 2 years of age

OBJECTIVE

To identify factors leading to readmission for tracheostomized, ventilator-dependent infants <2 years of age.

STUDY DESIGN

Retrospective cohort study of 117 tracheostomized, ventilator-dependent infants followed through 2 years of age.

RESULTS

Home ventilator use (at hospital discharge, 6 and 12 months of age), inhaled steroid use (at 12 and 24 months of age), oxygen dependence (at 6 and 12 months of age) and tracheostomy (at discharge, 6 and 12 months of age) were increased risks for rehospitalization. Equipment malfunction throughout the first 2 years also contributed to readmissions. Viral infection, with rhinovirus/enterovirus the most commonly identified pathogen, was the most common etiology for rehospitalization. Diuretic use and initial comorbid diagnoses were not associated with increased risk of rehospitalization.

CONCLUSION

The risk for rehospitalization for infants requiring tracheostomy and ventilator support was affected by prolonged oxygen use, prolonged ventilator dependence, inhaled steroid use and equipment malfunction, and was equally distributed throughout the first 2 years of life.

A comparison of 7-day versus 10-day course of low-dose dexamethasone for chronically ventilated preterm infants

OBJECTIVE

The objective of the study was to compare the effect of two different dexamethasone regimens on respiratory outcomes of ventilator-dependent preterm infants.

STUDY DESIGN

Retrospective study of ventilated preterm infants <29 weeks gestational age treated with either 7-day or 10-day dexamethasone course. Primary outcome was days to successful extubation. Other outcomes included rate of successful extubation and need for repeat steroid therapy.

RESULTS

Fifty-nine infants were identified; 32 (54%) received 7 days of dexamethasone and 27 (46%) received 10 days of dexamethasone. Both groups had comparable baseline demographics and clinical characteristics. Mean time to successful extubation was similar between the two groups (5.1±2.7 days in 7-day group and 6.0±3.7 days in 10-day group, P=0.42). Successful extubation by end of treatment (56% versus 67%, P=0.44) and need for repeat steroid therapy (47% versus 33%, P=0.43) were also similar.

CONCLUSION

7-day and 10-day course of dexamethasone have comparable efficacy in facilitating extubation of ventilator-dependent preterm infants.

FBXL4 defects are common in patients with congenital lactic acidemia and encephalomyopathic mitochondrial DNA depletion syndrome

Mutations in FBXL4 have recently been recognized to cause a mitochondrial disorder, with clinical features including early onset lactic acidosis, hypotonia, and developmental delay. FBXL4 sequence analysis was performed in 808 subjects suspected to have a mitochondrial disorder. In addition, 28 samples from patients with early onset of lactic acidosis, but without identifiable mutations in 192 genes known to cause mitochondrial diseases, were examined for FBXL4 mutations. Definitive diagnosis was made in 10 new subjects with a total of 7 novel deleterious variants; 5 null and 2 missense substitutions. All patients exhibited congenital lactic acidemia, most of them with severe encephalopathic presentation, and global developmental delay. Overall, FBXL4 defects account for at least 0.7% (6 out of 808) of subjects suspected to have a mitochondrial disorder, and as high as 14.3% (4 out of 28) in young children with congenital lactic acidosis and clinical features of mitochondrial disease. Including FBLX4 in the mitochondrial diseases panel should be particularly important for patients with congenital lactic acidosis.

[Rheumatoid arthritis involving tibialis posterior tendon: study on the early diagnostic value of power Doppler ultrasonography and comparison with surgery]

Objective: To explore the value of power Doppler ultrasonography (PDUS) in the early diagnosis of tibialis posterior tendon injury induced by rheumatoid arthritis (RA). Method: From January 2014 to December 2015, a total of 48 cases (60 feet) of RA tendinopathy group were selected as the research subjects from Guanghua Hospital; 12 cases(20 feet) of non-RA tendinopathy group and 10 cases (20 feet) of healthy volunteers were selected as control group.The blood flow signals of pannus were observed by PDUS to determine whether the tendon was injured or the degree of the injury. The following indexes were compared and analyzed by Chi-square testing: (1)positive rate of blood flow signal; (2)grade of blood flow signal; (3)spatial distribution of blood flow signal: diffusibility or local. Results: Of 70 cases(100 feet) in the study, the positive blood flow signals were only in the RA(88.3%) and non-RA group(40.0%) .Grade Ⅲ in RA was 20.0%, while this was not observed in non-RA . Grade Ⅱ in RA and non-RA was 36.7% and 10.0% , respectively. There were significant differences in the positive rate and grades between RA and non-RA group (P<0.01). The spatial distribution of blood flow signal in RA was significantly different from that in non-RA. In RA, they can be detected in the whole tendon.However, they were mainly distributed around the scaphoid in non-RA. In this study, three patients with grade Ⅲwere treated with surgery. The intraoperative findings were consistent with the preoperative ultrasound results. Conclusions: PDUS can be used to detect the neovascular formation of tendon synovitis. It can detect the early tendon injury before the appearance of foot deformity induced by RA, which can guide clinical early intervention treatment and prevent the occurrence of deformity and other serious consequences.

Selecting optimal surgical procedures for intraductal papillary mucinous neoplasm (IPMN): An analysis based on the Surveillance, Epidemiology, and End Result registry database

INTRODUCTION

Intraductal papillary mucinous neoplasm (IPMN) is a field defect disease of pancreas that has malignant potential. Many studies have recommended surgery as the preferred treatment. We investigated whether a total pancreatectomy (TP) can improve patient prognosis compared to a pancreatoduodenectomy (PD) and the indications for each approach.

PATIENTS AND METHODS

We obtained data of 548 malignant IPMN patients who underwent either a TP or a PD from SEER database. The survival rates were analyzed using the Kaplan-Meier method and a Cox regression model. Cases were subdivided to investigate the advantages of each procedure.

RESULTS

The surgical procedures (PD and TP) did not significantly affect either cancer-specific survival (CSS) times or overall survival (OS) times in both Kaplan-Meier analysis and Cox regression (Kaplan-Meier: PCSS = 0.919, POS = 0.996; Cox: PCSS = 0.735, POS = 0.820). In the subgroup analyses, patients in stage T4 and AJCC stage III in the TP group had a longer survival time than did those in the PD group (33 months vs 14 months), but not significant (T4: PCSS = 0.124, AJCC III: PCSS = 0.102). In addition, PD had the trend to be better for poorly differentiated patients (Pos = 0.055) and older patients.

CONCLUSION

TP did not offer any significant OS and CSS benefits as compared to PD. However, for patients in stage T4 and AJCC stage III, TP may extend survival time in some degree. In older or histologically poorly differentiated patients, PD may be preferable to TP. The results are rational, but still warrant further verification due to limited sample volumes of specific subgroups.

Synthesis and Assay of SIRT1-Activating Compounds

The NAD(+)-dependent deacetylase SIRT1 plays key roles in numerous cellular processes including DNA repair, gene transcription, cell differentiation, and metabolism. Overexpression of SIRT1 protects against a number of age-related diseases including diabetes, cancer, and Alzheimer's disease. Moreover, overexpression of SIRT1 in the murine brain extends lifespan. A number of small-molecule sirtuin-activating compounds (STACs) that increase SIRT1 activity in vitro and in cells have been developed. While the mechanism for how these compounds act on SIRT1 was once controversial, it is becoming increasingly clear that they directly interact with SIRT1 and enhance its activity through an allosteric mechanism. Here, we present detailed chemical syntheses for four STACs, each from a distinct structural class. Also, we provide a general protocol for purifying active SIRT1 enzyme and outline two complementary enzymatic assays for characterizing the effects of STACs and similar compounds on SIRT1 activity.

Spotlight on ultrasonic fracture behaviour of nanowires: their size-dependent effect and prospect for controllable functional modification

A ‘bubble-jet impacted’ model reveals the specific fragmentation evolution behaviors of nanowires.

Serum lipid profile in gynecologic tumors: a retrospective clinical study of 1,550 patients

BACKGROUND

The study was performed to characterize and compare the serum lipid profile in gynecologic cancers and benign diseases.

MATERIALS AND METHODS

A total of 1,550 age-matched females were included in this study: 760 patients with gynecologic cancers and 790 patients with benign diseases. Serum levels of triglycerides (TG), high density lipoprotein cholesterol (HDL-c), low density lipoprotein cholesterol (LDL-c), total cholesterol (TC), and lipoprotein (a) were measured.

RESULTS

Compared to gynecologic benign disease group, gynecologic cancer group was associated with higher level of TG (p = 0.0002), as well as lower level of HDL-c (p < 0.0001), LDL-c (p = 0.004) and TC (p = 0.003). Compared to benign ovarian tumor group, ovarian cancer group had significantly lower levels of HDL-c (p < 0.0001), LDL-c (p = 0.0009), and TC (p < 0.0001), as well as a trend of higher level of lipoprotein (a) (p = 0.10). Compared to endometriosis group, endometrial cancer group showed higher levels of TG (p < 0.0001) and lower levels of HDL-c (p = 0.002). There was no significant difference in any lipid parameters between cervical cancer group and uterine leiomyomas group.

CONCLUSION

In conclusion, compared with benign diseases, gynecologic cancers are associated with a disordered lipid profile characterized by higher TG and lipoprotein (a) levels, and lower HDL-c, LDL-c, and TC levels. The association is most conspicuous in ovarian cancers. Endometrial cancer is accompanied by alterations only in TG and HDL-c levels, while cervical cancer does not appear to be associated with disordered lipid profile.

Upregulation of mitogen-inducible gene 6 triggers antitumor effect and attenuates progesterone resistance in endometrial carcinoma cells

Researches regarding mitogen-inducible gene 6 (Mig-6) have confirmed its role as a tumor suppressor and progesterone resistance factor in endometrium. In this study, after confirming the downregulation of Mig-6 protein in endometrial carcinoma (EC) tissues, the expression of Mig-6 was upregulated in Ishikawa cells by pCMV6-Mig-6 plasmid. We observed the increased apoptosis, decreased proliferation and invasion potential of Ishikawa cells after upregulation of Mig-6. The proapoptosis ability of P4 significantly enhanced by 39.36%, the antiproliferation ability increased by 37.90% and the anti-invasion ability increased by 48.89%, suggesting the antiprogesterone resistance potential of Mig-6 in endometrium. In addition, the results suggested that Mig-6 may induce Ishikawa cell apoptosis through the mitochondrial pathway, inhibit cell proliferation via the extracellular signal-regulated kinase pathway and the anti-invasion potential may associate with matrix metalloproteinase (MMP)-2 and MMP-9 downexpression. Therefore, upregulation of Mig-6 may add a new strategy to suppress endometrial tumorigenesis and attenuate the progesterone resistance during P4 treatment.

Satisfactory Usage of a Lacerated Kidney for Transplantation: A Case Report

BACKGROUND

Organ shortage is the main bottleneck in the wait-list for transplantation; therefore, expanding the donor pool is an effective way to solve the problem. Usage of the traumatized liver for transplantation has been applied, but the use of lacerated kidneys for transplant donor is rarely reported.

METHODS

We reported a successful case of donation after brain death. The donor committed suicide by jumping from a campus dormitory building. One of the donated kidneys was severely injured. Two lacerations measured 4 × 1 × 1 cm in the medial margin of the graft and 1 × 1 × 1.5 cm in the front side of the graft, respectively. After repair with continuous absorbable suture, the lacerated kidney was transplanted to a recipient.

RESULTS

The post-transplantation renal function gradually recovered. Furthermore, serious complications, such as large amounts of hemorrhage, delayed graft function, or urinary fistula did not occur. The serum creatinine dropped from 1232 μmol/L to 120 μmol/L and maintained normal range after surgery. In addition, the daily urine output was normal. At day 12 after operation, the patient was discharged.

CONCLUSIONS

Our case shows that the use of a lacerated donor kidney appears to be feasible, but long-term effects need further observation.

Comparison of plain radiography and CT in postoperative evaluation of ankle fractures

AIM

To compare postoperative plain radiographs with computed tomography (CT) post-processing images in evaluating the quality of anatomical reduction and internal fixation of ankle fractures.

MATERIALS AND METHODS

A total of 168 patients who sustained closed ankle fracture and were treated with open reduction and internal fixation in East Hospital were reviewed. Postoperative plain radiographs and CT post-processing images were evaluated. The observation was performed under volume-rendering mode and multiplanar reconstruction mode. The assessment was performed by two independent orthopaedic surgeons. The inter- and intra-observer variations were analysed by kappa statistics. The differences between plain radiographs and CT post-processing images were compared using χ(2) test (McNemar's test).

RESULTS

Inter- and intra-observer agreement was almost perfect (0.813-1.000) using CT post-processing images, which was higher than that using plain radiographs (0.323-0.848). More non-anatomical reduction could be recognised in the supination-external rotation (SER), supination-adduction (SAD), pronation-external rotation (PER), and overall groups (p<0.05) and more poor internal fixation could be recognised in the SER, SAD, and overall groups (p<0.05) using CT post-processing images than using radiographs.

CONCLUSION

More residual articular step, fracture fragment displacement, and poor internal fixation could be detected by CT post-processing images than plain radiographs.

MLN4924 induces Noxa upregulation in acute myelogenous leukemia and synergizes with Bcl-2 inhibitors

MLN4924 (pevonedistat), an inhibitor of the Nedd8 activating enzyme (NAE), has exhibited promising clinical activity in acute myelogenous leukemia (AML). Here we demonstrate that MLN4924 induces apoptosis in AML cell lines and clinical samples via a mechanism distinct from those observed in other malignancies. Inactivation of E3 cullin ring ligases (CRLs) through NAE inhibition causes accumulation of the CRL substrate c-Myc, which transactivates the PMAIP1 gene encoding Noxa, leading to increased Noxa protein, Bax and Bak activation, and subsequent apoptotic changes. Importantly, c-Myc knockdown diminishes Noxa induction; and Noxa siRNA diminishes MLN4924-induced killing. Because Noxa also neutralizes Mcl-1, an anti-apoptotic Bcl-2 paralog often upregulated in resistant AML, further experiments have examined the effect of combining MLN4924 with BH3 mimetics that target other anti-apoptotic proteins. In combination with ABT-199 or ABT-263 (navitoclax), MLN4924 exerts a synergistic cytotoxic effect. Collectively, these results provide new insight into MLN4924-induced engagement of the apoptotic machinery that could help guide further exploration of MLN4924 for AML.

Health-related quality of life and related factors among elderly people in Jinzhou, China: a cross-sectional study

OBJECTIVES

With rapid reductions in fertility and mortality, China has to face the dramatic ageing of its population. Although an ageing population is associated with greater life expectancy, and reflects a huge improvement in people's living standards and health care services, it also means that more elderly people suffer from non-communicable diseases (NCDs). The prolonged course of illness and disability associated with chronic diseases may significantly reduce health-related quality of life (HRQoL) among elderly people. The aims of this study were to evaluate HRQoL of elderly people living in Jinzhou, and to identify the predictors of HRQoL.

STUDY DESIGN

Cross-sectional study with stratified sampling.

METHODS

A cross-sectional survey was conducted among 1015 elderly people (≥60 years) living in the three administrative regions (Linghe, Guta and Taihe) of Jinzhou. A demographic questionnaire and Short Form-36 were employed to collect demographic variables and evaluate HRQoL, respectively. Multiple stepwise linear regression analysis was performed to estimate factors related to HRQoL of the subjects.

RESULTS

Lowest HRQoL scores were obtained in the following dimensions: general health (65.44), role-emotional (69.74) and role-physical (70.20). Multiple stepwise regression showed that factors associated with HRQoL of elderly people were medical health checks, age, socio-economic status, NCDs, and various unhealthy lifestyle behaviours such as smoking, excessive drinking and insufficient exercise.

CONCLUSIONS

This study described overall HRQoL of elderly people in Jinzhou, and found that medical health checks, age, socio-economic status, NCDs, smoking, excessive drinking and insufficient exercise affected HRQoL. These findings will provide a basis for recommendations regarding health management of elderly people, and will also help local government to devise appropriate health intervention strategies for promoting the health status of elderly people in this region.

First Report of Apple chlorotic leaf spot virus in Hawthorn in China

Apple chlorotic leaf spot virus (ACLSV) is the type species of the genus Trichovirus in the Betaflexiviridae family (1). ACLSV is distributed worldwide in most pome and stone fruit trees of the Rosaceae family, including apple, pear, peach, plum, cherry, apricot, and hawthorn (3). In 2012, a de novo assembly of the fruit transcriptome of a hawthorn (Crataegus pinnatifida) accession maintained in the National Hawthorn Germplasm Repository at Shenyang was conducted using Illumina-based RNA-seq data, and it resulted that a 7,543 nt of the genomic sequence of ACLSV was assembled. To confirm the result of Illumina RNA-Seq analysis, nine pairs of primers were designed according to the assembled sequence of ACLSV to amplify the genomic sequence of ACLSV by RT-PCR with total RNA extracted from hawthorn leaves as template (2). The full-length sequence of the isolate of ACLSV from hawthorn assembled with the sequences of the RT-PCR fragments was also 7,543 nt (GenBank Accession No. KM207212), which shows 99.5% nucleotide identity with the sequence assembled from Illumina RNA-seq data. The isolate of ACLSV from hawthorn was named SY01, which shows about 75% nucleotide identity with the sequences of ACLSV isolated from apple (GenBank Accession No. KJ522693), peach (JN634760), and plum (M58152). The nucleotide sequences of coat protein and RNA polymerase genes of SY01 are about 83 and 88% identical with those of ACLSV isolates in GenBank, respectively. A pair of primers HF/HR (ACCGGCGTCTTTTGCAAACT/TGGGTTCCAGAGTTTGAATGCA), which amplified a 210-bp fragment, was designed according to the sequence of SY01 to detect ACLSV in hawthorns. With RT-PCR, ACLSV was detected in 6 of the 30 accessions of hawthorn, and the nucleotide identity among PCR fragments was 92%. In addition, leaves from six RT-PCR positive plants reacted positively when tested by DAS-ELISA with polyclonal antisera (X-Y Biotechnology, Shanghai, China) raised against ACLSV. These findings, representing the first report of the presence of ACLSV in hawthorn in China, illustrate the need to develop virus-free trees of hawthorn for cultivation and germplasm distribution of this important Rosaceae family plant. References: (1) E. B. Carstens. Arch. Virol. 155:133, 2010. (2) H. Dai et al. PLoS ONE 8(9):e72910, 2013. (3) A. T. Katsiani et al. Plant Pathol. 63:63, 2014.

The FEN1 E359K germline mutation disrupts the FEN1-WRN interaction and FEN1 GEN activity, causing aneuploidy-associated cancers

Polymorphisms and somatic mutations in Flap Endonuclease 1 (FEN1), an essential enzyme involved in DNA replication and repair, can lead to functional deficiencies of the FEN1 protein and a predisposition to cancer. We identified a FEN1 germline mutation which changed residue E359 to K in a patient whose family had a history of breast cancer. We determined that the E359K mutation, which is in the protein-protein domain of FEN1, abolished the interaction of FEN1 with Werner Syndrome protein (WRN), an interaction which is critical for resolving stalled DNA replication forks. Furthermore, although the flap endonuclease activity of FEN1 E359K was unaffected, it failed to resolve bubble structures, which requires the FEN1 gap dependent endonuclease (GEN) activity. To determine the etiological significance of E359K, we established a mouse model containing this mutation. E359K mouse embryonic fibroblasts (MEF) were more sensitive to DNA cross-linking agents that cause replication forks to stall. Cytological analysis suggested that the FEN1-WRN interaction was also required to for telomere stability; mutant cell lines had fragile telomeres, increased numbers of spontaneous chromosomal anomalies and higher frequencies of transformation. Moreover, the incidence of cancer was significantly higher in mice homozygous for FEN1 E359K than in wild-type mice, suggesting that the FEN1 E359K mutation is oncogenic.

Childhood obesity increases left-ventricular mass irrespective of blood pressure status

Adults with a left-ventricular mass index (LVMI) in grams normalized to height in meters(2.7) (LVMI g/m(2.7)) >51 g/m(2.7) are more prone to cardiovascular and cerebrovascular events. We delineated the odds for cardiac structural sequelae amongst apparently normal white and African-American (AA) children with varying body mass indices (BMI) and office blood pressures. A total of 2,071 children with normal echocardiograms were categorized into risk groups based on BMI and systolic blood pressures (SBPs). Predictors of cardiac sequelae examined were age, sex, race, and z-scores (z) for BMI, SBP, and diastolic blood pressure. Cardiac sequelae measures included (LVMI g/m(2.7)) >51 g/m(2.7), (LVMI) (g/m(2.7)) z, left atrial size (LA(ht)) (mm) z, and relative wall thickness z. Mean age was 14 ± 2 years with 56 % being male and 13 % being AA. Children were divided into "controls" (n = 1,059) and risk groups based on BMI and SBP. Odds ratio for LVMI (g/m(2.7)) > 51.0 g/m(2.7), varied from 5.3 up to 8.5 in children with increased BMI. Both increased BMI and SBP z were associated with increased LVMI (g/m(2.7)) z; however, BMI z had a stronger association. Increased BMI z and AA race were associated with greater LA(ht) (mm) z. AA controls had a nonsignificantly increased LVMI z and a significantly increased LA(ht) (mm) and RWT z. Being overweight or obese is associated with cardiac sequelae in children to the extent known to be associated with adverse outcomes in adults. Healthy AA children have unique cardiac structural differences.

Establishing best practices and guidance in population modeling: an experience with an internal population pharmacokinetic analysis guidance

This tutorial describes the development of a population pharmacokinetic (Pop PK) analysis guidance within Pfizer, which strives for improved consistency and efficiency, and a more systematic approach to model building. General recommendations from the Pfizer internal guidance and a suggested workflow for Pop PK model building are discussed. A description is also provided for mechanisms by which conflicting opinions were captured and resolved across the organization to arrive at the final guidance.

CPT: Pharmacometrics & Systems Pharmacology (2013) 2, e51; doi:10.1038/psp.2013.26; advance online publication 3 July 2013

In vitro chemosensitivity assay of ascites in epithelial ovarian cancer

OBJECTIVE

This study aimed to investigate the predictive value of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for chemosensitivity test in ascites.

MATERIALS AND METHODS

The relationship of the in vitro sensitivity results and the clinicopathological characteristics, objective response rates (ORRs) of chemotherapy, and time to progression (TTP) were retrospectively analyzed in 120 epithelial ovarian cancer (EOC) patients. The clinical response criterion was based on the Response Evaluation Criteria in Solid Tumors (RECIST) standard. The log-rank test and Kaplan-Meier curve were used to estimate TTP.

RESULTS

MTT assays revealed that tumor cells from ascites of primary and type II EOC were more sensitive to paclitaxel (PTX) and carboplatin (CBDCA) than relapse (p = 0.01 and p < 0.01, respectively) and type I (p = 0.03, p = 0.02, respectively) EOC. p53 positive expression and Ki67 high expression were associated with high PTX (p = 0.01 and p < 0.01, respectively) and CBDCA (p = 0.03 and p < 0.01, respectively) sensitivity. Ki67 weak positive immunostaining was associated with topotecan (p < 0.01), gemcitabine (p < 0.01), and doxorubicin (p < 0.01) resistance. Chemosensitivity to CBDCA/PTX was associated with the ORR ofneo-adjuvant (p = 0.03) and adjuvant (p = 0.02) chemotherapy. The MTT assay results of ascites were consistent with the clinical response (p = 0.04) and TTP (p = 0.04) in patients with platinum-resistant relapse EOC tumors.

CONCLUSIONS

Evaluation of the chemosensitivity of ascites in EOC by MTT can aid the establishment of individualized clinical chemotherapeutic plans for platinum-resistant relapse patients.

Cigarette smoke exposure hinders long-term allograft survival by suppressing indoleamine 2, 3-dioxygenase expression

Cigarette smoke causes cancer and increases the vulnerability of smokers to infections. Epidemiologic studies have shown that smoking is one of major risk factors for late allograft rejection. Despite statistical data that associate smoking with allograft rejection, no any study has been conducted to prove that cigarette smoke directly causes allograft rejection in a cause-effect manner. In particular, investigation into immunologic mechanisms underlying smoke-related allograft rejection is lacking. Here we found that second hand smoke (SHS) hindered long-term islet allograft survival induced by CD154 costimulatory blockade plus donor-specific splenocyte transfusion (DST), although it failed to alter acute islet allograft rejection. SHS did not directly interfere with vigorously alloreactive T-cell proliferation in vivo and in vitro. Neither naturally occurring nor induced CD4+CD25+ Treg cell numbers were significantly reduced by SHS. However, SHS suppressed mRNA and protein expression of indoleamine 2, 3-dioxygenase (IDO) and its activity upon transplantation while IDO overexpression in islet allografts restored their long-term survival induced by CD154 blockade. Therefore, SHS prevents long-term allograft survival by inhibiting IDO expression and activity. Thus, our study for the first time demonstrates that SHS shortens allograft survival in a cause-effect manner and unveils a novel immunologic mechanism underlying smoking-related allograft rejection.

In vitro suppression of drug-induced methaemoglobin formation by Intralipid(®) in whole human blood: observations relevant to the 'lipid sink theory'

To provide further evidence for the lipid sink theory, we have developed an in vitro model to assess the effect of Intralipid® 20% on methaemoglobin formation by drugs of varying lipid solubility. Progressively increasing Intralipid concentrations from 4 to 24 mg.ml⁻¹ suppressed methaemoglobin formation by the lipid soluble drug glyceryl trinitrate in a dose-dependent manner (p < 0.001). Both dose and timing of administration of Intralipid to blood previously incubated with glyceryl trinitrate for 10 and 40 min resulted in significant suppression of methaemoglobin formation (p < 0.0001 and p < 0.05, respectively). Mathematical modelling demonstrated that the entire process of methaemoglobin formation by glyceryl trinitrate was slowed down in the presence of Intralipid. Intralipid did not significantly suppress methaemoglobin formation induced by 2-amino-5-hydroxytoluene (partially lipid soluble) or sodium nitrite (lipid insoluble; both p > 0.5). This work may assist determination of the suitability of drugs taken in overdose for which Intralipid might be deployed.

Assessment of lateral geniculate nucleus atrophy with 3T MR imaging and correlation with clinical stage of glaucoma

BACKGROUND AND PURPOSE

Although previous animal studies have shown structural changes in ocular hypertension such as atrophy of the LGN, such changes have not been thoroughly studied in human glaucoma patients nor correlation made with clinical stage. Our aim was to investigate prospectively LGN atrophy in patients with POAG using 3T MR imaging and correlation with the clinical stage of disease.

MATERIALS AND METHODS

Twenty-six patients with known POAG and 26 age-matched healthy volunteers were included in this institutional review board-approved study. All subjects underwent imaging on a 3T MR imaging system with a PD and GM sequence. LGN height and volume were measured by 2 blinded neuroradiologists. Measurements were compared and correlated with clinical glaucoma severity as assessed by static threshold visual field parameters.

RESULTS

Average maximum LGN height in patients with glaucoma on PD images was 4.36 ± 0.61 mm (right) and 4.31 ± 0.61 mm (left), significantly less (P < 10⁻³) than respective measurements of 5.05 ± 0.41 and 4.99 ± 0.41 mm in volunteers. With the GM sequences, such respective measurements were also less (P < 10⁻³) in patients with glaucoma (4.20 ± 0.71 mm right, 4.00 ± 0.85 mm left) versus respective measurements in volunteers (4.88 ± 0.51 mm right, 4.77 ± 0.47 mm left). Average LGN volumes in the patient group were 98.0 ± 27.2 mm³ (right) and 93.7 ± 25.8 mm³ (left) with the PD sequence versus respective measurements of 85.2 ± 27.1 and 80.5 ± 23.6 mm³ with the GM sequence. All height and volume measurements were greater in volunteers (P < 10⁻³). In the patient group, both maximum height and volume of the LGN with both sequences were significantly correlated with cumulative clinical glaucoma stage (P < .05).

CONCLUSIONS

MR imaging measurements of LGN height and volume are diminished in patients with glaucoma, with the extent of atrophy correlating to clinical stage, suggesting a novel imaging marker of disease severity.

Efficacy and safety of the dipeptidyl peptidase-4 inhibitor PF-734200 added to metformin in Type 2 diabetes

AIMS

  PF-734200 is a potent and selective oral dipeptidyl peptidase-4 (DPP-4) inhibitor. This study assessed the efficacy and safety of PF-734200 at dose rates of 20 and 30 mg/day in subjects with Type 2 diabetes mellitus inadequately controlled on metformin monotherapy.

METHODS

  This was a placebo-controlled, double-blind, randomized, multicentre, 12 week study. Subjects with Type 2 diabetes mellitus were eligible if screening glycosylated haemoglobin (HbA(1c) ) was 7-11% (53.0-96.7 mmol/mol) and they had been receiving metformin monotherapy for ≥2 months. Subjects receiving metformin and an insulin secretagogue or metformin and thiazolidinedione needed to have a screening HbA(1c) of 6.5-9.5% (47.5-80.3 mmol/mol), measured prior to discontinuing the insulin secretagogue or thiazolidinedione. The primary end-point of the study was a change from baseline to week 12 in HbA(1c) levels.

RESULTS

  Baseline characteristics for 289 subjects randomized to PF-734200 or placebo groups were similar (mean age 56.5 years, mean body mass index 32.2 kg/m(2) and mean HbA(1c) 8.2%, 66.1 mmol/mol). In the predefined per protocol data set, least-squares mean HbA(1c) at week 12 was reduced by 0.79 (8.6 mmol/mol 95% confidence interval -1.10 to -0.49, -12.0 to -5.4 mmol/mol) and 0.92% (10.1 mmol/mol; -1.23 to -0.61, -13.4 to -6.7 mmol/mol) in the 20 and 30 mg groups, respectively, compared with placebo. Differences from placebo were statistically significant (P<0.0001), but the differences between the 20 and 30 mg groups were not. The intent-to-treat analysis yielded similar findings.

CONCLUSIONS

  The HbA(1c) was significantly and meaningfully reduced by both doses of PF-734200, but 20 mg appears to be the more appropriate therapeutic dose for Type 2 diabetes mellitus, contingent upon confirmation by long-term controlled studies.

Strong impact of acute kidney injury on survival after liver transplantation

Acute kidney injury (AKI) is a major complication in orthotopic liver transplantation (OLT). In an evaluation of Acute Kidney Injury Network (AKIN) criteria in liver transplanted patients, we retrospectively analyzed the usefulness of these criteria to predict survival of 193 consecutive patients at a single center who underwent primary OLT for clinical parameters and peak AKI. Postoperative AKI according to AKIN occurred in 60.1% of the patients, namely, stages 1, 2, and 3 in 30%, 13% and 17.1% respectively. Using multivariate logistic regression, AKIN stage 1 and 2 AKI were independently associated with the pre-OLT Model for End-Stage Liver Disease (MELD) score and age, while stage 3 AKI was independently associated with MELD and Acute Physiology and Chronic Health Evaluation (APACHE) II scores. The 28-day and 1-year mortality post-OLT of AKI patients were 15.5% and 25.9% respectively compared with 0% and 3.9% among non-AKI patients (P < .05 for both). The survival rates of non-AKI and stages 1, 2, and 3 AKI subjects were 96%, 85.5%, 84%, and 45.3%, respectively. Cox regression analysis showed independent risk factors for mortality during the first year after transplantation to include post-OLT AKI (12.1; P < .05), post-OLT infection (HR 4.7; P < .01), pre-OLT hypertension (HR 4.4; P < .01) hazard ratio [HR] and post-OLT APACHE II ≥10 (HR 3.6; P < .05). We concluded that AKI as defined by the AKIN criteria is a major complication of OLT linked to a poor outcomes. It remains to be evaluated whether aggressive perioperative therapy to prevent AKI can improve survival among OLT patients.

Essential roles of Jab1 in cell survival, spontaneous DNA damage and DNA repair

Jun activation domain-binding protein 1 (JAB1) is a multifunctional protein that participates in the control of cell proliferation and the stability of multiple proteins. JAB1 overexpression has been implicated in the pathogenesis of human cancer. JAB1 regulates several key proteins and thereby produces varied effects on cell cycle progression, genome stability and cell survival. However, the biological significance of JAB1 activity in these cellular signaling pathways is unclear. Therefore, we developed mice that were deficient in Jab1 and analyzed the null embryos and heterozygous cells. This disruption of Jab1 in mice resulted in early embryonic lethality due to accelerated apoptosis. Loss of Jab1 expression sensitized both mouse primary embryonic fibroblasts and osteosarcoma cells to γ-radiation-induced apoptosis, with an increase in spontaneous DNA damage and homologous recombination (HR) defects, both of which correlated with reduced levels of the DNA repair protein Rad51 and elevated levels of p53. Furthermore, the accumulated p53 directly binds to Rad51 promoter, inhibits its activity and represents a major mechanism underlying the HR repair defect in Jab1-deficient cells. These results indicate that Jab1 is essential for efficient DNA repair and mechanistically link Jab1 to the maintenance of genome integrity and to cell survival.