Nomogram for evaluating coronary revascularisation necessity based on multi-parameter coronary CT angiography.

AIM: To build a nomogram model to improve the evaluation of revascularisation necessity using multi-parameter coronary computed tomography (CT) angiography (CCTA). MATERIALS AND METHODS: In this retrospective study, 335 patients who underwent CCTA and required revascularisation within 1 month were selected and allocated to the revascularisation group; 208 patients who did not undergo revascularisation were allocated to the non-revascularisation group. CCTA parameters, including CCTA stenosis, plaque qualitative-quantitative characteristics, and fractional flow reserve derived from CT angiography (CT-FFR), for both groups were analysed and compared. Independent risk factors for evaluating revascularisation were obtained using univariate and multivariable regression analysis, after which multi-parameter models were built. Finally, a nomogram was created with these independent risk factors using the R programming language. RESULTS: Plaque analysis was performed successfully for 543 patients with 1,072 target plaques. The performance of the multi-parameter model (AUC 0.894, p<0.001) was significantly higher than that of models based on stenosis (AUC 0.804, p<0.001), plaque qualitative/quantitative characteristics (AUC 0.754/0.789, p<0.001), or CT-FFR (AUC 0.848, p<0.001) alone, to evaluate the necessity of revascularisation. The independent risk factors were CCTA stenosis (OR 1.004, p=0.04), positive remodelling (OR 2.474, p<0.001), total plaque volume (OR 1.001, p<0.001), non-calcified plaque volume proportion (OR 1.019, p<0.001), and CT-FFR (OR 0.001, p<0.001). Subsequently, a nomogram based on these factors was created. CONCLUSION: The multi-parameter CCTA model improved performance in evaluating revascularisation necessity. The nomogram based on these factors is shows promise in clinical settings.

Prediction of acute myocardial infarction by multi-parameter coronary computed tomography angiography.

AIM: To investigate the performance of multi-parameter coronary computed tomography angiography (CCTA), including stenosis, plaque qualitative-quantitative characteristics, and fractional flow reserve derived from CCTA (FFRct), to predict acute myocardial infarction (AMI) and build a combined model. MATERIALS AND METHODS: Thirty patients with AMI 90 days after CCTA and 120 matched patients without AMI were enrolled retrospectively. Multiple CCTA parameters were analysed and compared. Independent risk factors were obtained through univariate and multivariate regression analyses, after which a multi-parameter model was built. RESULTS: A total of 150 patients were analysed successfully. The multi-parameter CCTA model (area under the curve, 0.944; p<0.001) had a higher predictive value than each single parameter (p<0.001, all). Independent risk factors were intra-plaque dye penetration (IDP; odds ratio [OR], 8.373; p=0.002), lipid plaque volume (LPV; OR, 1.263; p<0.001), and FFRct ≤0.83 (OR, 8.092; p=0.001). CONCLUSION: This one-stop multi-parameter CCTA model, comprising IDP, LPV, and FFRct as independent risk factors, has good performance to predict AMI.

Myocardial CT perfusion imaging and atherosclerotic plaque characteristics on coronary CT angiography for the identification of myocardial ischaemia.

AIM: To investigate the value of myocardial computed tomography (CT) perfusion imaging (CTP) and atherosclerotic plaque characteristics (APCs) identified on coronary CT angiography (CCTA) for the detection of myocardial ischaemia by using single-photon-emission CT (SPECT) as a reference. MATERIALS AND METHODS: Thirty-six patients (63.9% males) undergoing combined stress dynamic CTP and CCTA were enrolled and analysed. Myocardial blood flow (MBF) from CTP was quantified and compared between normal and abnormal segments. The ability of CTP and APCs to detect ischaemia was compared to that of SPECT. RESULTS: Nineteen patients with 78 segments had perfusion abnormalities on CTP. A significant difference was seen in MBF values between normal (118.51±27.86 ml/100 ml/min) and hypoperfused (79.60±21.35 ml/100 ml/min) segments (t=15.832, p<0.05). The sensitivity and specificity for identifying ischaemia were 90.91% and 94.97%, respectively, on a per-segment basis, resulting in a r value of 0.737 (p<0.05). On a per-vessel basis, the sensitivity and specificity for detecting ischaemia were 86.67% and 84.62%, respectively, for CTP; 93.33% and 58.97%, respectively, for CCTA; and 86.67% and 87.18%, respectively, for CTP combined with CTA, with an area under the receiver-operator characteristic curve (AUC) being 0.87 (p<0.05) and 0.887 (p<0.05) for CTP and its combination with CTA, respectively. On CCTA, 55 vessels with APCs were detected, with an AUC of 0.737 (p<0.05) for APCs combined with CCTA stenosis and 0.802 (p<0.05) for APCs combined with CTP. CONCLUSIONS: Dynamic stress CTP shows good correlation with SPECT for the detection of ischaemia. Additionally, combining APCs with CCTA stenosis has the ability to discriminate ischaemic stenosis.

Severe hoarseness associated with the streamlined liner of the pharyngeal airway (SLIPATM).

Hoarseness is a common post-operative complication in patients who receive general anesthesia. In most cases, the symptoms are temporary and improve within several days. This report describes two patients with prolonged hoarseness following use of the streamlined liner of the pharyngeal airway (SLIPATM). We present the first case of a 56-year-old female patient who developed arytenoid cartilage dislocation resulting in prolonged hoarseness and dysphagia after using a SLIPA™ during a laparoscopic myomectomy. In the second case, we report on a 65-year-old male patient who was scheduled for a laparoscopic cholecystectomy. Left vocal fold paralysis or paresis resulting from recurrent laryngeal nerve injury associated with use of a SLIPA™ caused persistent hoarseness. It should be noted that recurrent laryngeal nerve injury or arytenoid cartilage dislocation are possible complications associated with use of the SLIPATM in case of persistent hoarseness.

Early detection of acute radiation-induced lung injury with multi-section CT perfusion imaging: An initial experience.

AIM: To explore the value of 64-section computed tomography (CT) perfusion imaging (CTPI) in the early diagnosis of acute radiation-induced lung injury (ARILI). MATERIALS AND METHODS: Fifty-one patients with oesophageal cancers or malignant thymomas received postoperative radiation therapy with a 60-62 Gy dose and underwent CTPI at pre- and post-radiation therapy time points (week 0, week 4, week 8, and week 12 respectively). The CTPI values were prospectively compared and analysed in order to evaluate the diagnostic utility of CTPI in the early diagnosis of ARILI. RESULTS: Eighteen cases (18/51) of ARILI were diagnosed. The mean values of relative regional blood flow (rrBF), relative regional volume (rrBV), and relative regional permeability surface (rrPS) in the ARILI group were correspondingly higher than those of the non-ARILI group. At week 4, rrBF, rrBV, and rrPS in the ARILI group were significantly higher than those at pre-radiation (each p < 0.05). In the non-ARILI group, rrBF and rrBV were higher than those at pre-radiation (each p < 0.05); however, rrPS was not statistically different from that of pre-irradiation. Applying the diagnostic threshold value of rrPS = 1.22, the sensitivity, specificity, and positive and negative predictive values of CTPI for early diagnosis of ARILI were better than those of CT. CONCLUSION: CTPI metrics may reflect haemodynamic changes in the post-irradiation lung and can detect cases of early ARILI that appear normal at CT. CTPI is a promising technique for early diagnosis of ARILI.

CT imaging and histopathological features of renal epithelioid angiomyolipomas.

AIM: To describe computed tomography (CT) imaging and histopathological manifestations of renal epithelioid angiomyolipomas (EAMLs) for better understanding and cognition in the diagnosis of this new category of renal tumours. MATERIALS AND METHODS: Clinical data and CT images from 10 cases of EAML were retrospectively analysed. All patients underwent CT with and without contrast medium administration, with multiplanar reconstruction (MPR) when needed. RESULTS: Plain CT manifestations of EAMLs were a higher density of mass (10-25 HU) than renal parenchyma, bulging contour of the involved kidney, absence of fat, distinct edges without a lobulate appearance. Contrast-enhanced CT features were markedly heterogeneous enhancement (from rapid wash-in to slow wash-out), large tumour size without lobular appearance, complete capsule with distinct margins and frequent mild necrotic areas. Histopathological features were epithelioid cells with eosinophilic cytoplasm, large and deeply stained nuclei, and dense arrangement of tumour cells with patchy necrosis; diffuse sheets of epithelioid cells were positive for HMB-45 (melanoma-associated antigen) and negative for epithelial membrane antigen (EMA) staining. CONCLUSION: Multiple specific CT features correlated well with the histopathology and may play an important role in the primary diagnosis of EAMLs.

Effect of CYP3A4*1G on the fentanyl consumption for intravenous patient-controlled analgesia after total abdominal hysterectomy in Chinese Han population.

WHAT IS KNOWN AND OBJECTIVE: Clinical investigations into postoperative intravenous patient-controlled analgesia (PCA) have indicated interindividual differences in fentanyl consumption. Cytochrome P450 3A4 (CYP3A4) is the main metabolism enzyme of fentanyl, and single nucleotide polymorphisms within the CYP3A4 gene may contribute to the variability of fentanyl analgesic efficacy. The aim of this study was to investigate whether the most common genetic variation in Chinese, CYP3A4*1G, has an impact on the fentanyl consumption for intravenous PCA in Chinese Han women undergone abdominal total hysterectomy. METHODS: A total of 79 female patients (American Society of Anesthesiologist physical status I or II) scheduled to undergo elective abdominal total hysterectomy were enrolled. All patients received combined spinal-epidural anaesthesia with bupivacaine. Intravenous fentanyl PCA was provided postoperatively for satisfactory analgesia. The doses of fentanyl consumption were recorded 2, 4, 24 and 48 h after the initiation of PCA postoperatively. Pain at rest and adverse effects were measured with rating scales. CYP3A4*1G was screened by means of direct sequencing and further confirmed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS AND DISCUSSION: Forty-six patients were GG homozygotes, 27 patients were GA heterozygotes, and six patients were AA homozygotes, respectively. The distribution of the CYP3A4*1G allele was consistent with Hardy-Weinberg equilibrium (P>0·05). At 2 and 4 h, the doses of fentanyl required for patients with GA/AA genotypes were 80·0 (45·0, 112·5) µg and 120·0 (80, 173·8)µg, respectively, and significantly lower than those for GG homozygotes [91·3 (80·0, 125·0) µg and 169·0 (112·5, 226·3) µg, respectively, P<0·05]. There was trend of decreasing fentanyl consumption at 24 and 48h in patients with GA/AA genotypes, relative to GG homozygotes, but the difference was not statistical significant (P>0·05). WHAT IS NEW AND CONCLUSIONS: CYP3A4*1G has an impact on the analgesic effect of fentanyl in Chinese Han subjects. Further validation of our results in a well-powered study would be helpful.

Unrelated cord blood transplantation in CML: Japan Cord Blood Bank Network analysis.

We analysed 86 patients with CML who received unrelated cord blood transplantation (UCBT), identified through a registry of the Japan Cord Blood Bank Network. At transplantation, the median patient age was 39 years (range, 1-67 years); 38 patients were in chronic phase (CP), 13 in the accelerated phase (AP) and 35 in blast crisis (BC). Median duration from diagnosis to UCBT was 1.5 years (range, 0.2-14.6 years). A nucleated cell (NC) dose of more than 3.0 x 10(7) per kg was sufficient to achieve neutrophil (91%) and platelet recovery (86%), whereas the lower dose of NC achieved only 60 and 61%, respectively. The duration and type of pre-transplant treatment did not affect neutrophil or platelet recovery. Results of multivariate analysis indicated that older patients (>50 years) had a higher incidence of transplant-related mortality. Advanced-disease stage and lower doses of NCs were significantly associated with lower leukaemia-free and event-free survival. At 2-year survival for patients in CP, AP and BC was 71, 59 and 32%, respectively (P=0.0004). A pre-transplant European Group for Blood and Marrow Transplantation scoring system was effective in predicting the outcome of UCBT. We conclude that UCBT is a reasonable alternative therapy for patients with CML.

Intraparenchymal epidermoid cysts in the brain: diagnostic value of MR diffusion-weighted imaging.

AIM: To evaluate the value of magnetic resonance (MR) diffusion-weighted imaging (DWI) and apparent diffusion coefficients (ADC) maps in the diagnosis of intraparenchymal epidermoid cysts (ECs). MATERIALS AND METHODS: Six cases of histopathologically proven intraparenchymal ECs were studied. All patients were examined with conventional MR (T1WI, T2WI, contrast-enhanced T1WI) and DWI sequences. Along with the mean ADC values (mADC) of the ECs, the cerebrospinal fluid (CSF) and grey matter (GM) were measured. Qualitative and quantitative assessments, as well as MRI findings, were retrospectively analysed using a double blind method by three radiologists in consensus. RESULTS: Four lesions were located in the cerebellum, among them, one was accompanied by an arachnoid cyst; one huge lesion crossed the parenchyma of the frontal and temporal lobes; the other was located in the left temporal lobe. Two lesions had a homogeneous CSF-like intensity on both T1WI and T2WI. The other four were of mixed-intensity on both T1WI and T2WI. All lesions were strikingly hyperintense on DWI, and iso- or slightly hypointense on ADC (relative to the brain). The mADCs of the ECs were significantly higher than that of GM, but significantly lower than that of CSF. Three cases (3/6) were accurately diagnosed using conventional MR sequences without DWI, but in the remaining three cases, correct diagnosis could only be made with help of DWI. CONCLUSION: DWI sequences can facilitate the diagnosis of intraparenchymal ECs, thus alerting surgeons of the risk of chemical meningitis at surgery. The MR findings of intraparenchymal ECs are basically as the same as those of extracerebral ECs, but the former is likely to have a mixed signal. The hyperintense signal of ECs on DWI is probably caused by the T2 shine-through effect in tumour tissue.

Genomic variations within DEFB1 are associated with the susceptibility to and the fatal outcome of severe sepsis in Chinese Han population.

Sepsis is a systemic inflammatory response syndrome to infection. Human beta-defensin 1 (DEFB1) is a multifunctional mediator in infection and inflammation, which has been largely explored in ex vivo studies. The present case-control study was designed to investigate whether DEFB1 genomic variations are associated with the susceptibility to and the outcome of severe sepsis in 211 patients with severe sepsis and 157 ethnic-matched healthy controls. After correcting for multiple testing, the -44G/C was the only polymorphism found to show significant associations with both the susceptibility to and the fatal outcome of severe sepsis (P=0.0049, odd ratio (OR) 1.971 and P=0.002, OR 2.406, respectively). Haplotype -20A/-44C/-52G showed a protective role against severe sepsis (P=0.0066, OR 0.6751), whereas haplotype -20G/-44G/-52G served as a risk factor for the fatal outcome of severe sepsis (P=0.0052, OR 2.427). These findings provide further evidence that beta-defensin 1 may play a role in the pathogenesis of severe sepsis.

Room-temperature broadband emission of an InGaAs/GaAs quantum dots laser.

We report the first demonstration to our knowledge of an ultrabroad emission laser using InGaAs/GaAs quantum dots by cycled monolayer deposition. The device exhibits a lasing wavelength coverage of approximately 40 nm at an approximately 1160 nm center wavelength at room temperature. The broadband signature results from the superposition of quantized lasing states from highly inhomogeneous dots.

Differential expression of alpha- and beta-defensins in human peripheral blood.

BACKGROUND: Human defensin peptides with broad-spectrum antimicrobial activity have been implicated in the human defence response towards microbial invasion. Two families of defensins designated alpha- and beta-defensins, respectively, have been identified. Little is known about the expression of both defensin families in human peripheral blood. The purpose of this study was to examine the expression of alpha- and beta-defensin genes in human peripheral blood. MATERIAL AND METHODS: Fifty-one healthy blood donors were screened for defensin expression. Blood from defensin responders was stimulated by lipopolysaccharide or heat-inactivated Pseudomonas aeruginosa ex vivo. Levels of mRNA were assessed by semiquantitative RT-PCR. Southern blot analysis and sequencing were used to confirm the identity of defensin gene transcripts. Western blotting analysis was used to detect the expression of defensin peptides. RESULTS: beta-defensin was undetected in human peripheral blood without stimulation. Following stimulation by lipopolysaccharide or heat-inactivated bacterial cells, the majority (88.2%) of healthy individuals had a detectable expression for beta-defensin-1 gene and 39.2% for beta-defensin-2 gene, compared with none for beta-defensin-3. beta-defensin-1 and -2 mRNAs in the stimulated human peripheral blood of responders became detectable at 3 h and showed a maximum at 6 h following induction by 100 ng mL-1 of lipopolysaccharide or bacterial cells. In contrast, human alpha-defensins 1-3 mRNA are constitutively expressed in peripheral leukocytes but not up-regulated by lipopolysaccharide or bacterial cells. CONCLUSIONS: In human peripheral blood, beta-defensin-1 and -2 genes were transiently transcribed and translated following the induction of lipopolysaccharide or heat-inactivated bacterial cells, whereas alpha-defensins 1-3 genes were constitutively transcribed, and beta-defensin-3 gene was not expressed. The inducible expression of beta-defensin-1 and -2 genes showed interindividual variability.

IV-VI semiconductor growth on silicon substrates and new mid-infrared laser fabrication methods

This paper reviews results from research conducted at the University of Oklahoma on the development of new IV-VI semiconductor (lead salt) epitaxial growth and laser fabrication procedures that can ultimately lead to dramatic increases in mid-IR laser operating temperatures. Work has focused on growth of IV-VI semiconductor laser structures on silicon substrates using buffer layers that contain BaF2. Recent experiments show that it is possible to obtain high crystalline quality IV-VI semiconductor layer structures on (111)-oriented silicon substrates using molecular beam epitaxy (MBE) or on (100)-oriented silicon using a combination of MBE and liquid phase epitaxy (LPE). Experimental data for IV-VI semiconductor layer structures grown on silicon substrates including crystalline quality information as determined by high resolution X-ray diffraction (HRXRD) measurements and absorption edge information as determined by Fourier transform infrared (FTIR) transmission measurements are presented. Results show that these materials can be used to fabricate lasers that cover the 3 microns (3333 cm-1) to 16 microns (625 cm-1) spectral range. Removal of IV-VI semiconductor laser structures from the silicon growth substrate by dissolving BaF2 buffer layers with water is also demonstrated. This allows epitaxially-grown laser structures to be sandwiched between two heat sinks with a minimum of thermally resistive IV-VI semiconductor material. Theoretical modeling predicts that IV-VI lasers fabricated this way will have maximum continuous wave (cw) operating temperatures at least 60 degrees higher than those of IV-VI lasers fabricated on PbSe or PbTe substrates.