The Effects of Peanut Oligopeptides on Exercise-Induced Fatigue in Mice and Its Underlying Mechanism.

The aim of this study was to clarify the anti-fatigue effect of peanut oligopeptides (POPs) in mice and to investigate its possible underlying mechanism. A total of 150 male ICR mice were randomly assigned into five groups: control, whey protein (0.50 g/kg·bw), and three peanut peptide groups (0.25, 0.50, and 1.00 g/kg·bw). All the mice were treated with intra-gastric administration for 30 days. Following the intervention, a weight-loaded swimming test, blood lactate concentration, glycogen content, the activities of antioxidant factors and energy metabolism enzymes, and the function of mitochondria in the skeletal muscle were examined. The results show that POP intervention significantly prolonged the exhaustive swimming time, decreased blood lactate concentration levels, regulated the process of energy metabolism, and increased the level of antioxidant enzymes, muscle glycogen, and expressions of mtTFA and NRF-1 in the mitochondria of the gastrocnemius muscle. The results suggest that POPs produce an anti-fatigue effect in the animals, and they may exert this effect through the mechanism of improving the animals' antioxidant capacity to reduce oxidative damage levels and regulating the process of energy metabolism.

ACTA2 mutation is responsible for multisystemic smooth muscle dysfunction syndrome with seizures: A case report and review of literature.

BACKGROUND: ACTA2 gene is a specific gene that encodes actin α2. Multisystem smooth muscle dysfunction syndrome (MSMDS) is a multisystem disease characterized by aortic and cerebrovascular lesions caused by ACTA2 gene mutations. There have been many reports of cardiac, pulmonary and cerebrovascular lesions caused by MSMDS; however, few studies have focused on seizures caused by MSMDS. CASE SUMMARY: Our patient was a girl aged 7 years and 8 mo with recurrent cough, asthma and seizures for 7 years. She was diagnosed with severe pneumonia, congenital heart disease, cardiac insufficiency, and malnutrition in the local hospital. Cardiac ultrasonography revealed congenital heart disease, patent ductus arteriosus (with a diameter of 0.68 cm), left coronary arteriectasis, patent oval foramen (0.12 cm), tricuspid and pulmonary regurgitation, and pulmonary hypertension. Cerebral magnetic resonance imaging and magnetic resonance angiography indicated stiffness in the brain vessels, together with multiple aberrant signaling shadows in bilateral paraventricular regions. A heterozygous mutation (c.536G>A) was identified in the ACTA2 gene, resulting in generation of p.R179H. Finally, the girl was diagnosed with MSMDS combined with epilepsy. The patient had 4 episodes of seizures before treatment, and no onset of seizure was reported after oral administration of sodium valproate for 1 year. CONCLUSION: MSMDS has a variety of clinical manifestations and unique cranial imaging features. Cerebrovascular injury and white matter injury may lead to seizures. Gene detection can confirm the diagnosis and prevent missed diagnosis or misdiagnosis.

Myocardial area at risk and salvage in reperfused acute MI measured by texture analysis of cardiac T2 mapping and its prediction value of functional recovery in the convalescent stage.

OBJECTIVES: We sought to distinguish area at risk from salvage myocardial zone and to predict left ventricle functional recovery in the convalescent stage by Texture Analysis (TA) of T2-Mapping. METHODS: One hundred and six patients diagnosed with AMI and treated with percutaneous coronary intervention (PCI) underwent acute cardiac magnetic resonance imaging (CMR) and 45 of whom had a subsequent CMR scan following recovery. Cine imaging, T2-Mapping, T2-weighted STIR imaging, and LGE imaging were performed. In the texture analysis, regions of interest (infarcted, salvageable, and remote) were drawn by two blinded, independent readers. RESULTS: Seven independent texture features on T2-Mapping were selected: Perc.50%, S(2,2)InvDfMom, S(2.-2)AngScMom, S(4,0)Entropy, 45dgrLngREmph, 45dgr_Fraction and 135dr_GLevNonU. Among them, the average value of 135dr_GLevNonU in the infarct zone, AAR zone, and the remote zone was: 61.96±26.03, 31.811±18.933 and 99.839±26.231, respectively. Additionally, 135dr_GLevNonU provided the highest area under the curve (AUC) from the receiver operating characteristic curve (ROC curve) for distinguishing AAR from the infarct zone in each subgroup (all patients, patients with MVO and)were 0.845 ± 0.052 0.855 ± 0.083 and 0.845 ± 0.066, respectively, and were more promise than T2-Mapping mean (p<0.001). The AUC for differentiating AAR from the remote zone is 0.942±0.041. Texture features are not associated with convalescent decreased strain, ejection fraction (EF) or left ventricle remodeling (LVR) in analysis (p>0.05). CONCLUSION: TA of T2-mapping can distinguish AAR from both the infarct zone and the remote myocardial zone without LGE imaging in reperfused AMI. However, these features are not able to predict patients' functional recovery in the convalescent stage.

The Antioxidant Effects of Whey Protein Peptide on Learning and Memory Improvement in Aging Mice Models.

This study investigated the antioxidant effects of whey protein peptide on learning and memory in aging C57BL/6N mice. A total of 72 SPF male C57BL/6N mice were used. Twelve mice were randomly selected as the control group, and the other mice were intraperitoneally injected with D-galactose (100 mg/kg body weight for 6 weeks), during which, the mice in the control group were intraperitoneally injected with the same amount of normal saline. After 6 weeks, the blood was taken from the epicanthus and the serum MDA level was measured, according to which, the mice were randomly divided into the model control group, the whey protein group (1.5 g/kg body weight), and three Whey protein peptide (WHP) intervention groups (0.3 g/kg body weight, 1.5 g/kg body weight, 3.0 g/kg body weight). The water solution of the test sample was administered by oral gavage every day. The intervention period was 30 days, during which, the model control group, the whey protein group, and the whey protein peptide group continued receiving intraperitoneal injections of D-galactose, while the control group continued receiving intraperitoneal injections of normal saline. After the intervention, behavioral experiments were conducted in the following order: open field test, water maze test, and new object recognition test. After the behavioral experiment, the morphology of hippocampal formation was observed by HE staining and TUNEL labeling. Oxidative stress-related indexes in the serum, liver, and brain were detected. Expression levels of the cholinergic system-related enzymes and proinflammatory cytokines in brain tissue were detected. Western blot was used to detect the expression of synaptic plasticity-related proteins in the mouse brain. The results showed that WHP could significantly improve the accumulation of MDA and PC, increase the activities of SOD and GSH-Px, resist oxidative stress injury, and enhance the potential of endogenous antioxidant defense mechanisms. WHP can significantly improve the decline of aging-related spatial exploration, body movement, and spatial and non-spatial learning/memory ability. Its specific mechanism may be related to reducing the degeneration of hippocampal nerve cells, reducing the apoptosis of nerve cells, improving the activity of AChE, reducing the expression of inflammatory factors (TNF-α and IL-1ß) in brain tissue, reducing oxidative stress injury, and improving the expression of p-CaMKⅡ and BDNF synaptic plasticity protein. These results indicate that WHP can improve aging-related oxidative stress, as well as learning and memory impairment.

Radioprotective Effect of Whey Hydrolysate Peptides against γ-Radiation-Induced Oxidative Stress in BALB/c Mice.

Radiation therapy is widely used in the treatment of tumor diseases, but it can also cause serious damage to the body, so it is necessary to find effective nutritional supplements. The main purpose of this study is to evaluate the protective effect of whey hydrolysate peptides (WHPs) against 60Coγ radiation damage in mice and explore the mechanism. BALB/c mice were given WHPs by oral gavage administration for 14 days. Then, some mice underwent a 30-day survival test after 8 Gy radiation, and other mice received 3.5 Gy radiation to analyze the changes in body weight, hematology and bone marrow DNA after three and 14 days. In addition, through further analysis of the level of oxidative stress and intestinal barrier function, the possible mechanism of the radioprotective effect of WHPs was explored. The study found WHPs can prolong survival time, restore body weight, and increase the number of peripheral blood white blood cells and bone marrow DNA content in irradiated mice. In addition, WHPs can significantly improve the antioxidant capacity, inhibit pro-inflammatory cytokines and protect the intestinal barrier. These results indicate that WHPs have a certain radioprotective effect in mice, and the main mechanism is related to reducing oxidative damage.

Jackfruit (Artocarpus heterophyllus Lam.) oligopeptides regulate immune responses via Th cell stimulation, cytokine secretion and antibody production.

This study aimed to observe the immunomodulatory effects of oligopeptides derived from jackfruit (Artocarpus heterophyllus Lam.) (JOPs). 200 female BALB/c mice in five groups were respectively given deionized water (control), whey protein (0.20 g per kg body weight (BW)) and JOPs at doses of 0.20, 0.40, and 0.80 g per kg BW by intragastric administration on a daily basis. 7 tests were conducted to determine the immunomodulatory effects of JOPs on immune organ indexes, cellular and humoral immune responses, macrophage phagocytosis, and natural killer (NK) cell activity. Spleen T lymphocyte sub-populations and serum cytokine and immunoglobulin levels were tested to study how JOPs improved the immune system. We found that JOPs could significantly enhance innate and adaptive immune responses in mice by the improvement of cell-mediated and humoral immunity, macrophage phagocytosis capacity and NK cell activity. The immunomodulatory effects may be based on increased T and Th cell percentages, serum interleukin (IL)-1α, IL-10, tumor necrosis factor (TNF)-α, production of immunoglobulin (Ig) M, IgG, and IgA, and depressed interferon (IFN)-γ secretion. These results suggest that dietary JOPs could be valuable as potential immunomodulators.

Utilization of MR imaging in myodural bridge complex with relevant muscles: current status and future perspectives.

The aim of this study is to review and discuss the literature on the utilization of magnetic resonance imaging (MRI) in investigating the structure and feasible function of the myodural bridge complex (MDBC) with relevant muscles, which will be useful to understand the function of the MDB. The myodural bridge (MDB) is a soft tissue connective bridge that provides a fascial continuity between the musculature/ligament and cervical spinal dura mater (SDM) in the suboccipital areas. All of these involved structures are referred to as the MDBC. It would transfer tensile forces effectively from involved suboccipital muscles/ligament to SDM during head movement. Despite present achievements, its anatomic and functional role is still unclear. MRI enables not only in vivo visualization of ligaments, musculature and spinal dura with conventional T1W, T2W and PDW imaging, but also functional evaluation of MDBC with relevant muscles, such as muscles' fatty infiltration, cross-sectional area changes and injuries. Though some functional MRI techniques have not been used for the MDBC with relevant muscles now, these techniques have great potential to better understand function of MDBC including its suspected clinical role. MRI is likely the most powerful tool to study MDBC and relevant muscles with only limited exploration so far.

Synergistic anticancer effect of exogenous wild-type p53 gene combined with 5-FU in human colon cancer resistant to 5-FU in vivo.

AIM: To investigate the anticancer effect of a recombinant adenovirus-mediated p53 (rAd-p53) combined with 5-fluorouracil (5-FU) in human colon cancer resistant to 5-FU in vivo and the mechanism of rAd-p53 in reversal of 5-FU resistance. METHODS: Nude mice bearing human colon cancer SW480/5-FU (5-FU resistant) were randomly assigned to four groups (n = 25 each): control group, 5-FU group, rAd-p53 group, and rAd-p53 + 5-FU group. At 24 h, 48 h, 72 h, 120 h and 168 h after treatment, 5 mice were randomly selected from each group and sacrificed using an overdose of anesthetics. The tumors were removed and the protein expressions of p53, protein kinase C (PKC), permeability-glycoprotein (P-gp) and multidrug resistance-associated protein 1 (MRP1) (Western blot) and apoptosis (TUNEL) were determined. RESULTS: The area ratios of tumor cell apoptosis were larger in the rAd/p53 + 5-FU group than that in the control, 5-FU and rAd/p53 groups (P < 0.05), and were larger in the rAd/p53 group than that of the control group (P < 0.05) and the 5-FU group at more than 48 h (P < 0.05). The p53 expression was higher in the rAd/p53 and the rAd/p53 + 5-FU groups than that of the control and 5-FU groups (P < 0.05), and were higher in the rAd/p53 + 5-FU group than that of the rAd/p53 group (P < 0.05). Overexpression of PKC, P-gp and MRP1 was observed in the 5-FU and control groups. In the rAd/p53 + 5-FU group, the expression of P-gp and MRP1 was lower that of the control and 5-FU groups (P < 0.05), and the expression of PKC was lower than that of the control, 5-FU and rAd/p53 groups at more than 48 h (P < 0.05). In the rAd/p53 group, the expression of P-gp and MRP1 was lower that of the control and 5-FU groups at more than 48 h (P < 0.05), and the expression of PKC was lower than that of the control and 5-FU groups at more than 120 h (P < 0.05). CONCLUSION: 5-FU combined with rAd-p53 has a synergistic anticancer effect in SW480/5-FU (5-FU resistance), which contributes to reversal of 5-FU resistance.

DTI Study of Cerebral Normal-Appearing White Matter in Hereditary Neuropathy With Liability to Pressure Palsies (HNPP).

The majority of previous studies on hereditary neuropathy with liability to pressure palsies (HNPP) were focused on peripheral nerves, whereas cerebral alterations in HNPP have been less attended to. In this work, Diffusion tensor imaging (DTI) was used to detect the changes in WM, especially in the normal-appearing white matter (NAWM) in HNPP patients for its sensitivity in probing the microstructure of WM, the sensitive metric was searched for probing cerebral alterations and the regional distribution of cerebral abnormalities was identified. Twelve HNPP patients and 12 age- and gender-matched healthy controls underwent the conventional MRI, DTI scan, and electrophysiological examination. The conventional MRI images were first analyzed to identify abnormal intense regions and the NAWM regions. NAWM refers to the white matter regions that do not include the lesions on conventional MRI. The apparent diffusion coefficient and fractional anisotropy (FA) values of the NAWM were then measured and compared between patient and control groups. The sensitivity and specificity of 3 methods and the cerebral regional distribution of MR signal abnormalities were further analyzed. Hyperintense foci were observed on T2 weighted image and fluid attenuated inversion recovery images in 6 patients. Compared to the controls, FA values of the patients were significantly lower in bilateral frontal, orbitofrontal, and temporal NAWMs; whereas the electrophysiological examination results of patients and controls exhibited no statistically significant difference. The sensitivity of FA value was higher than that of electrophysiological examination and conventional MRI. The majority of abnormal signals on conventional MRI images and abnormal FA values were located in the frontal and temporal lobes. The results of our study show cerebral WM changes in HNPP patients. FA value in DTI has been shown to be sensitive to the cerebral microstructural changes in HNPP. The frontal lobe is the predilection site that is most involved in HNPP.

Platelet count combined with right liver volume and spleen volume measured by magnetic resonance imaging for identifying cirrhosis and esophageal varices.

AIM: To determine whether the combination of platelet count (PLT) with spleen volume parameters and right liver volume (RV) measured by magnetic resonance imaging (MRI) could predict the Child-Pugh class of liver cirrhosis and esophageal varices (EV). METHODS: Two hundred and five cirrhotic patients with hepatitis B and 40 healthy volunteers underwent abdominal triphasic-enhancement MRI and laboratory examination of PLT in 10(9)/L. Cirrhotic patients underwent endoscopy for detecting EV. Spleen maximal width (W), thickness (T) and length (L) in mm together with spleen volume (SV) and RV in mm(3) were measured by MRI, and spleen volume index (SI) in mm(3) was obtained by W × T × L. SV/PLT, SI/PLT and RV × PLT/SV (RVPS) were calculated and statistically analyzed to assess cirrhosis and EV. RESULTS: SV/PLT (r = 0.676) and SI/PLT (r = 0.707) increased, and PLT (r = -0.626) and RVPS (r = -0.802) decreased with the progress of Child-Pugh class (P < 0.001 for all). All parameters could determine the presence of cirrhosis, distinguish between each class of Child-Pugh class, and identify the presence of EV [the areas under the curve (AUCs) = 0.661-0.973]. Among parameters, RVPS could best determine presence and each class of cirrhosis with AUCs of 0.973 and 0.740-0.853, respectively; and SV/PLT could best identify EV with an AUC of 0.782. CONCLUSION: The combination of PLT with SV and RV could predict Child-Pugh class of liver cirrhosis and identify the presence of esophageal varices.

Albumin and magnetic resonance imaging-liver volume to identify hepatitis B-related cirrhosis and esophageal varices.

AIM: To investigate whether liver lobe volume and albumin (ALB) could predict the presence and severity of liver cirrhosis, and esophageal varices. METHODS: Seventy-one cirrhotic patients with hepatitis B and 21 healthy individuals were enrolled in this study. All the participants underwent abdominal enhanced magnetic resonance imaging to measure each liver lobe volume, and biochemical workup for testing ALB and Child-Pugh class. All cirrhotic patients underwent upper gastrointestinal endoscopy to show the presence of cirrhotic esophageal varices. Right liver lobe volume (RV), left medial liver lobe volume (LMV), left lateral liver lobe volume (LLV), and caudate lobe volume (CV) were measured using enhanced magnetic resonance imaging. The ratios of RV to ALB (RV/ALB), LMV to ALB (LMV/ALB), LLV to ALB (LLV/ALB) and CV to ALB (CV/ALB) were calculated. Statistical analyses were performed to determine whether and how the combination of liver lobe volume measured using magnetic resonance imaging and albumin could predict the presence and severity of liver cirrhosis, and the presence of esophageal varices. RESULTS: RV, LMV, LLV and CV decreased (r = -0.51-0.373; all P < 0.05), while RV/ALB increased (r = 0.424; P < 0.05), with the progress of Child-Pugh class of liver cirrhosis. RV, LMV, CV, LLV/ALB and CV/ALB could identify presence of liver cirrhosis; LLV and LMV could distinguish Child-Pugh class A from B; RV, LMV, LLV, CV, RV/ALB and LLV/ALB could distinguish class A from C; RV and LLV/ALB could differentiate B from C; and RV, RV/ALB and CV/ALB could identify presence of esophageal varices (all P < 0.05). Among these parameters, CV/ALB could best identify the presence of liver cirrhosis, with an area under receiver operating characteristic curve (AUC) of 0.860, a sensitivity of 82.0% and a specificity of 83.0%. LLV could best distinguish class A from B, with an AUC of 0.761, a sensitivity of 74.4% and a specificity of 73.1%. RV could best distinguish class A from C, with an AUC of 0.900, a sensitivity of 90.3% and a specificity of 84.5%. LLV/ALB could best distinguish class B from C, with an AUC of 0.900, a sensitivity of 93.8% and a specificity of 81.5%. RV/ALB could best identify esophageal varices, with an AUC of 0.890, a sensitivity of 80.0% and a specificity of 83.5%. CONCLUSION: The combination of liver lobe volume and ALB has potential to identify presence and severity of cirrhosis, and presence of esophageal varices.

Is diffusion-weighted MRI superior to FDG-PET or FDG-PET/CT in evaluating and predicting pathological response to preoperative neoadjuvant therapy in patients with rectal cancer?

OBJECTIVE: This meta-analysis aimed to compare the diagnostic accuracy of diffusion-weighted magnetic resonance imaging (DW-MRI) and fluorodeoxyglucose-positron emission tomography (FDG-PET) or FDG-PET/computed tomography (CT) in evaluating and predicting pathological response to preoperative neoadjuvant chemoradiotherapy (NCRT) in patients with rectal cancer. METHODS: A comprehensive literature research was conducted to identify the relevant studies for this meta-analysis. Combined sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated. RESULTS: A total of 33 studies including 1564 patients met the inclusion criteria. The pooled sensitivity (81% [95% CI 74-86%] vs 85% [95% CI 75-91%]) and NPV (80% [95% CI 68-89%] vs 91% [95% CI 80-95%]) for FDG-PET or FDG-PET/CT were significantly lower than those for DW-MRI (P < 0.05). No differences were observed in pooled specificity and PPV between DW-MRI and FDG-PET or FDG-PET/CT. Further subgroup analyses showed that DW-MRI had higher sensitivity on adenocarcinomas alone than on those including mucinous-type adenocarcinomas (92% [95% CI 83-99%] vs 76% [95% CI 63-90%], P = 0.00). CONCLUSIONS: DW-MRI is superior to FDG-PET or FDG-PET/CT in predicting and evaluating pathological responses to preoperative NCRT in patients with rectal cancer. However, its relatively low specificity and PPV limit its application in clinic, making it currently inappropriate to monitor such patients, especially those with mucinous-type rectal adenocarcinomas.

The clinical value of diffusion-weighted imaging in combination with T2-weighted imaging in diagnosing prostate carcinoma: a systematic review and meta-analysis.

OBJECTIVE: We aimed to explore the role of diffusion-weighted imaging (DWI) in combination with T2-weighted imaging (T2WI) in detecting prostate carcinoma through a systematic review and meta-analysis. MATERIALS AND METHODS: The MEDLINE, EMBASE, Cancerlit, and Cochrane Library databases were searched for studies published from January 2001 to July 2011 evaluating the diagnostic performance of T2WI combined with DWI in detecting prostate carcinoma. We determined sensitivities and specificities across studies, calculated positive and negative likelihood ratios, and constructed summary receiver operating characteristic curves. We also compared the performance of T2WI combined with DWI with T2WI alone by analyzing studies that had also used these diagnostic methods on the same patients. RESULTS: Across 10 studies (627 patients), the pooled sensitivity of T2WI combined with DWI was 0.76 (95% CI, 0.65-0.84), and the pooled specificity was 0.82 (95% CI, 0.77-0.87). Overall, the positive likelihood ratio was 4.31 (95% CI, 3.12-5.92), and the negative likelihood ratio was 0.29 (95% CI, 0.20-0.43). In seven studies in which T2WI combined with DWI and T2WI alone were performed, the sensitivity and specificity of T2WI combined with DWI were 0.72 (95% CI, 0.67-0.82) and 0.81 (95% CI, 0.76-0.86), respectively, and the sensitivity and specificity of T2WI alone were 0.62 (95% CI, 0.55-0.68) and 0.77 (95% CI, 0.71-0.82), respectively. CONCLUSION: T2WI combined with DWI may be a valuable tool for detecting prostate cancer in the overall evaluation of prostate cancer, compared with T2WI alone. High-quality prospective studies of T2WI combined with DWI to detect prostate carcinoma still need to be conducted.

Can diffusion-weighted MR imaging and contrast-enhanced MR imaging precisely evaluate and predict pathological response to neoadjuvant chemotherapy in patients with breast cancer?

Clinical evidence regarding the value of MRI for therapy responses assessment in breast cancer is increasing. The objective of this study is to compare the diagnostic capability of diffusion-weighted MR imaging (DW-MRI) and contrast-enhanced MR imaging (CE-MRI) to evaluate and predict pathological response in breast cancer patients receiving neoadjuvant chemotherapy (NAC). We performed a meta-analysis of all available studies of the diagnostic performance of DW-MRI or CE-MRI to evaluate and predict pathological response to NAC in patients with breast cancer. We determined sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR-), diagnostic odds ratio (DOR) and constructed summary receiver operating characteristic curves using hierarchical regression models. Methodological quality was assessed by QUADAS tool. Thirty-four studies met the inclusion criteria and involved 1,932 pathologically confirmed patients in total. Methodological quality was relatively high. DW-MRI sensitivity was 0.93 (95 % CI 0.82-0.97) and specificity was 0.82 (95 % CI 0.70-0.90). Overall LR+ was 5.09 (95 % CI 3.09-8.38), LR- was 0.09 (95 % CI 0.04-0.22), and DOR was 55.59 (95 % CI 21.80-141.80). CE-MRI sensitivity was 0.68 (95 % CI 0.57-0.77) and specificity was 0.91 (95 % CI 0.87-0.94). Overall LR+ was 7.48 (95 % CI 5.29-10.57), LR- was 0.36 (95 % CI 0.27-0.48), and DOR was 20.98 (95 % CI 13.24-33.24). Our study confirms that DW-MRI is a high sensitive and CE-MRI is a high specific modality in predicting pathological response to NAC in breast cancer patients. The combined use of DW-MRI and CE-MRI has the potential to improve the diagnostic performance in monitoring NAC. Further large prospective studies are warranted to assess the actual value of this combination in breast cancer preoperative treatment screening.

Diagnostic value of diffusion-weighted magnetic resonance imaging compared with fluorodeoxyglucose positron emission tomography/computed tomography for pancreatic malignancy: a meta-analysis using a hierarchical regression model.

BACKGROUND AND AIM: To obtain diagnostic performance of diffusion-weighted magnetic resonance imaging (DWI) and fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the detection of pancreatic malignancy. METHODS: We performed a meta-analysis of all available studies of the diagnostic performance of DWI and PET/CT for pancreatic malignancy. MEDLINE, EMBASE, Cochrane library and some other databases were searched for initial studies. We determined sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR-), and constructed summary receiver operating characteristic curves (SROC) using hierarchical regression models. RESULTS: Across 16 studies with 804 patients, PET/CT sensitivity was 0.87 (95% confidence interval [CI], 0.82, 0.81) and specificity was 0.83 (95% CI, 0.71, 0.91). Overall, LR+ was 5.84 (95% CI, 4.59, 7.42) and LR- was 0.24 (95% CI, 0.17, 0.33). DWI sensitivity was 0.85 (95% CI, 0.74, 0.92) and specificity was 0.91 (95% CI, 0.71, 0.98). LR+ was 9.53 (95% CI, 2.41, 37.65) and LR- was 0.17 (95% CI, 0.09, 0.32). In subgroup analysis, the sensitivity of enhanced versus unenhanced PET/CT in the detection of pancreatic cancer was 0.91 (95% CI, 0.86, 0.96) versus 0.84 (95% CI, 0.78, 0.90) (P > 0.05), the specificity 0.88 (95% CI, 0.73, 1.00) versus 0.81 (95% CI, 0.69, 0.94) (P > 0.05). CONCLUSION: Positron emission tomography/computed tomography (PET/CT) was highly sensitive and DWI was a highly specific modality in diagnosing patients with pancreatic malignancy. PET/CT and DWI could play different roles in diagnosing pancreatic carcinoma. Enhanced PET/CT seems to be superior to unenhanced PET/CT. Further larger prospective studies are needed to establish its value for diagnosis in pancreatic cancer.

Value of diffusion-weighted imaging for the discrimination of pancreatic lesions: a meta-analysis.

OBJECTIVE: We aimed to explore the role of diffusion-weighted imaging (DWI) in the discrimination of pancreatic lesions through meta-analysis. METHODS: The MEDLINE, EMBASE, Cancerlit, and Cochrane Library databases, from January 2001 to August 2011, were searched for studies evaluating the diagnostic performance of DWI in the discrimination of pancreatic lesions. We determined sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR-), and constructed summary receiver operating characteristic curves. RESULTS: A total of 11 studies with 586 patients, who fulfilled all of the inclusion criteria, were considered for the analysis. No publication bias was found. The pooled sensitivity of DWI was 0.86 [95% (confidence interval (CI), 0.78, 0.91] and the pooled specificity was 0.91 (95% CI, 0.81, 0.96). Overall, LR+ was 9.8 (95% CI, 4.1, 23.3) and LR- was 0.15 (95% CI, 0.09, 0.26). The area under the curve of the summary receiver operating characteristic was 0.94 (95% CI, 0.91-0.96). In subgroup analysis, prospectively designed studies had the highest pooled sensitivity (0.87, 95% CI 0.75, 0.94) and specificity (0.96, 95% CI 0.91, 0.99) (P<0.05). Study sensitivity was not correlated with the prevalence of pancreatic lesions (R=0.1076, P=0.3247). CONCLUSION: A limited number of small studies suggest that DWI is a potentially technically feasible measure to differentiate malignant from benign pancreatic lesions. However, it is still controversial and is limited in that it can only distinguish certain lesions. High-quality prospective studies on DWI for the discrimination of pancreatic lesions still need to be conducted.

Value of magnetic resonance imaging for nodal staging in patients with head and neck squamous cell carcinoma: a meta-analysis.

OBJECTIVES: To evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) in detecting lymph node metastases in patients with head and neck squamous cell carcinoma (HNSCC). METHODS: MEDLINE, EMBASE, the CBM disc databases, and other databases were searched for relevant original articles published between January 1990 and January 2011. Meta-analysis methods were used to pool sensitivity and specificity and to construct summary receiver-operating characteristic, and to calculate positive and negative likelihood ratios (LR+ and LR-). We also compared the performance of MRI with other diagnostic methods (positron emission tomography, computed tomography, and ultrasound) by analyzing studies that had also used these diagnostic methods on the same patients. RESULTS: Across 16 studies, there was no evidence of publication bias (P = .15). Sensitivity and specificity of MRI for cervical lymph node status in patients with HNSCC across all studies were 76% (95% CI: 70%-82%) and 86% (95% CI: 73%-93%), respectively. Overall, Positive likelihood ratios was 5.47 (95% CI: 2.69-11.11) and positive negative likelihood ratios was 0.28 (95% CI: 0.21-0.36), respectively. The comparison of MRI performance with that of other diagnostic tools (positron emission tomography, computed tomography, and ultrasound) suggested no major differences against any of these methods. The Subgroup by using diffusion-weighted imaging had higher pooled sensitivity (0.86, 95% CI 0.78-0.92) than the subgroup without diffusion-weighted imaging. CONCLUSION: MRI has good diagnostic performance in the overall pretreatment evaluation of node staging with HNSCC. A limited number of small studies suggest DWI is superior to conventional imaging for nodal staging of HNSCC.

18 F-fluorodeoxyglucose positron emission tomography to evaluate recurrent gastric cancer: a systematic review and meta-analysis.

BACKGROUND AND AIM: We aimed to explore the role of the diagnostic accuracy of (18) F-fluorodeoxyglucose positron emission tomography ((18) F-FDG PET) in detecting recurrent gastric cancer through a systematic review and meta-analysis. METHODS: The MEDLINE, EMBASE, Cancerlit, and Cochrane Library database, from January 2001 to July 2011, were searched for studies evaluating the diagnostic performance of (18) F-FDG PET in detecting recurrent gastric cancer. We determined the sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR-), and constructed summary receiver operating characteristic curves. We also compared the performance of (18) F-FDG PET with computed tomography (CT) by analyzing studies that had also used these diagnostic methods on the same patients. RESULTS: Across nine studies (526 patients), the overall sensitivity of (18) F-FDG PET was 0.78 (95% confidence interval [CI]: 0.68-0.86), and the overall specificity was 0.82 (95% CI: 0.76-0.87). Overall, LR+ was 3.52 (95% CI: 2.68-4.63) and LR- was 0.32 (95% CI: 0.22-0.46). In studies in which both (18) F-FDG PET and other diagnostic tests were performed, the sensitivity and specificity of (18) F-FDG PET were 0.72 (95% CI: 0.62-0.80) and 0.84 (95% CI: 0.77-0.90), respectively; of contrast CT, they were 0.74 (95% CI: 0.64-0.83) and 0.85 (95% CI: 0.78-0.90), respectively; and of combined PET and CT, they were 0.75 (95% CI: 0.67-0.82) and 0.85 (95% CI 0.79-0.90), respectively. Study sensitivity was not correlated with the prevalence of recurrent gastric cancer. CONCLUSION: (18) F-FDG PET has good diagnostic performance in the overall evaluation of recurrent gastric cancer, but still has some limited performance compared with contrast CT. (18) F-FDG PET combined with CT might improve the diagnostic performance in detecting recurrent gastric cancer.