Long‐term impact and clinical significance of living donor liver transplantation with respect to donor liver restoration and spleen size: A prospective study

This study aimed to evaluate postoperative long‐term liver restoration and splenic enlargement and their clinical significance in living donor liver transplantation. One hundred and sixteen donors who had donated livers more than 5 years previously accepted the invitation to participate in this study. The liver restoration rate and the splenic enlargement rate were calculated as the rate with respect to the original volume. The mean liver restoration rate was 0.99 ± 0.12 and older age was associated with a higher incidence for liver restoration rate <0.95 (P = .005), whereas type of donor operation was not. The donors with liver restoration rate <0.95 showed lower serum albumin levels than those with liver restoration rate ≥0.95. The mean splenic enlargement rate was 1.10 ± 0.16. Right lobe donors demonstrated higher splenic enlargement rate (1.14 ± 0.18) than left lobe/lateral segment donors (1.06 ± 0.13). In the donors with splenic enlargement rate ≥1.10, platelet count was not fully restored to the preoperative level. In conclusion, older age increases the risk for incomplete postoperative liver restoration, which may be associated with a decrease in albumin more than 5 years after donation. Right lobe donation poses a risk of splenic enlargement, which is associated with incomplete restoration of platelet count.     

Development of an algorithm to automatically compress a CT image to visually lossless threshold

Background

To develop an algorithm to predict the visually lossless thresholds (VLTs) of CT images solely using the original images by exploiting the image features and DICOM header information for JPEG2000 compression and to evaluate the algorithm in comparison with pre-existing image fidelity metrics.

Methods

Five radiologists independently determined the VLT for 206 body CT images for JPEG2000 compression using QUEST procedure. The images were divided into training (n?=?103) and testing (n?=?103) sets. Using the training set, a multiple linear regression (MLR) model was constructed regarding the image features and DICOM header information as independent variables and regarding the VLTs determined with median value of the radiologists’ responses (VLT_rad) as dependent variable, after determining an optimal subset of independent variables by backward stepwise selection in a cross-validation scheme.The performance was evaluated on the testing set by measuring absolute differences and intra-class correlation (ICC) coefficient between the VLT_rad and the VLTs predicted by the model (VLT_model). The performance of the model was also compared two metrics, peak signal-to-noise ratio (PSNR) and high-dynamic range visual difference predictor (HDRVDP). The time for computing VLTs between MLR model, PSNR, and HDRVDP were compared using the repeated ANOVA with a post-hoc analysis. P?<?0.05 was considered to indicate a statistically significant difference.

Results

The means of absolute differences with the VLT_rad were 0.58 (95% CI, 0.48, 0.67), 0.73 (0.61, 0.85), and 0.68 (0.58, 0.79), for the MLR model, PSNR, and HDRVDP, respectively, showing significant difference between them (p?<?0.01). The ICC coefficients of MLR model, PSNR, and HDRVDP were 0.88 (95% CI, 0.81, 0.95), 0.85 (0.79, 0.91), and 0.84 (0.77, 0.91). The computing times for calculating VLT per image were 1.5?±?0.1 s, 3.9?±?0.3 s, and 68.2?±?1.4 s, for MLR metric, PSNR, and HDRVDP, respectively.

Conclusions

The proposed MLR model directly predicting the VLT of a given CT image showed competitive performance to those of image fidelity metrics with less computational expenses. The model would be promising to be used for adaptive compression of CT images.

     

Hydrolytic Stability of Methacrylamide and Methacrylate in Gelatin Methacryloyl and Decoupling of Gelatin Methacrylamide from Gelatin Methacryloyl through Hydrolysis

Gelatin methacryloyl (GelMA; GM) is a promising nature‐derived photocurable material that can mimic the extracellular matrix because GelMA features tailorable mechanical properties, proteolytic degradation, and good cell adhesion. GelMA contains not only methacrylamide but also methacrylate. However, the hydrolytic stability of methacrylamide and methacrylate groups of GelMA in aqueous solutions has not been scrutinized. Here, the structural change of GelMA through hydrolysis is investigated for the first time. The structural change of hydrolyzed GelMA is quantitatively identified using colorimetric and ¹H NMR methods. The methacrylate groups decompose markedly at high pH solutions, but the methacrylamide groups remain stable. Further, pure gelatin methacrylamide is successfully decoupled from GelMA for a better understanding of GelMA structure and future use for biomedical applications.     

Oral health behaviors and metabolic syndrome: the 2008–2010 Korean National Health and Nutrition Examination Survey

Objectives

This study examined whether oral health behaviors are associated with metabolic syndrome (MetS) in Korean adults involved in the 2008–2010 Korea National Health and Nutrition Examination Survey (KNHANES).

Materials and methods

A total of 18,742 subjects (8,034 men and 10,708 women) were included. MetS was defined according to the criteria of the American Heart Association/National Heart, Lung, and Blood Institute Scientific Statement for Asians. Oral health behavior was assessed using a questionnaire included in the KNHANES.

Results

Subjects with MetS brushed their teeth less frequently and used fewer secondary oral products than subjects without MetS (p?<?0.01). As frequency of toothbrushing and number of secondary oral products increased, body mass index, waist circumference, diastolic blood pressure, fasting plasma glucose, triglyceride, and white blood cell count decreased, but high-density lipoprotein–cholesterol increased (all p for trend <0.01). In the multivariable logistic regression models, as frequency of toothbrushing increased, the odds ratios (ORs) for MetS, abdominal obesity, and hyperglycemia are more than one after adjusting for age, gender, education, income, alcohol and tobacco use, physical activity, and the components of MetS. The ORs for MetS, abdominal obesity, and high blood pressure were more than one in subjects who do not use dental floss after adjusting for all covariates.

Conclusion

MetS is associated with infrequent daily toothbrushing and disuse of dental floss in South Korean.

Clinical relevance

Dentists may recommend evaluation for MetS in the patients with infrequent daily toothbrushing and disuse of dental floss.     

Characterization and bacterial anti-adherent effect on modified PMMA denture acrylic resin containing platinum nanoparticles

PURPOSE

This study characterized the synthesis of a modified PMMA (Polymethyl methacrylate) denture acrylic loading platinum nanoparticles (PtN) and assessed its bacterial inhibitory efficacy to produce novel antimicrobial denture base material.

MATERIALS AND METHODS

Polymerized PMMA denture acrylic disc (20 mm × 2 mm) specimens containing 0 (control), 10, 50, 100 and 200 mg/L of PtN were fabricated respectively. The obtained platinum-PMMA nanocomposite (PtNC) was characterized by TEM (transmission electron microscopy), SEM/EDX (scanning electron microscope/energy dispersive X-ray spectroscopy), thermogravimetric and atomic absorption spectrophotometer analysis. In antimicrobial assay, specimens were placed on the cell culture plate, and 100 µL of microbial suspensions of S. mutans (Streptococcus mutans) and S. sobrinus (Streptococcus sobrinus) were inoculated then incubated at 37℃ for 24 hours. The bacterial attachment was tested by FACS (fluorescence-activated cell sorting) analysis after staining with fluorescent probe.

RESULTS

PtN were successfully loaded and uniformly immobilized into PMMA denture acrylic with a proper thermal stability and similar surface morphology as compared to control. PtNC expressed significant bacterial anti-adherent effect rather than bactericidal effect above 50 mg/L PtN loaded when compared to pristine PMMA (P=.01) with no or extremely small amounts of Pt ion eluted.

CONCLUSION

This is the first report on the synthesis and its antibacterial activity of Pt-PMMA nanocomposite. PMMA denture acrylic loading PtN could be a possible intrinsic antimicrobial denture material with proper mechanical characteristics, meeting those specified for denture bases. For clinical application, future studies including biocompatibility, color stability and warranting the long-term effect were still required.     

Non-invasive assessment of liver fibrosis using acoustic structure quantification: comparison with transient elastography in chronic viral hepatitis

Purpose

The purpose of this study was to evaluate the diagnostic efficacy of acoustic structure quantification (ASQ) parameters [mode, average, and focal distribution (FD) ratio] in the staging of hepatic fibrosis in patients with chronic viral hepatitis and to compare it with transient elastography (TE) by using liver biopsy as reference standard.

Methods

We studied 62 patients with chronic viral hepatitis. Each patient underwent ASQ evaluation and liver biopsy; 54 of these patients received TE. Thirty-six participants without any liver disease were enrolled as normal group, who also underwent ASQ evaluation and TE. All three parameters of ASQ were compared with the histologic fibrosis grade according to the METAVIR scoring (F0–F4). Statistical analysis was performed to investigate the correlations and the diagnostic values of ASQ parameters and compare them to TE.

Results

All three ASQ parameters and TE were significantly correlated with liver fibrosis stage. Of the ASQ parameters, the mode parameter showed the best correlation (P < 0.001). On the area under the receiver operating characteristic curve (AUROC), the mode parameter of ASQ analysis showed both significant correlation and good accuracy for diagnosis of F ≥ 1, F ≥ 2, and F ≥ 3. These values were significantly better than those of the average and FD ratio parameters in F ≥ 1 and F ≥ 2 (P < 0.05). There was no statistically significant difference in AUROC between the mode parameter and TE in diagnosis of F ≥ 1, F ≥ 2, or F ≥ 3.

Conclusions

The mode parameter is the most reliable ASQ parameter, comparable to TE, as a non-invasive method for the detection and grading of liver fibrosis in patients with chronic viral hepatitis.

     

Predictive factors of intensive care unit admission in patients with haematological malignancies and pneumonia

Objective To describe early signs at the onset of pneumonia occurring in the haematology ward which could be associated with a transfer to the ICU.Design A 13-month preliminary prospective observational cohort study.Setting Department of haematology and (32-bed) medical intensive care unit (ICU).Patients Fifty-three of 302 patients hospitalised in the haematology ward who developed presumptive clinical evidence of pneumonia were enrolled.Measurements and results At the onset of the clinical evidence of pneumonia (day 1), we compared variables between patients requiring an ICU admission and those who did not. Twenty-four patients (45%) required a transfer to the ICU. Factors associated with ICU admission were: numbers of involved quadrants: 2.3 vs 1, P=0.001 and oxygenation parameters (initial level of O₂ supplementation: 3.5 vs 0.9 l/min, P<0.05), the presence of hepatic failure (58% vs 10%, P<0.01), Gram-negative bacilli isolated in blood culture (7 vs 1, P=0.01). In the multivariate analysis, a decrease of 10% in the SaO₂ and the requirement of nasal supplementary O₂ at the onset of acute respiratory failure increased the risk of admission to MICU, respectively, by 18 and by 14. The overall 6-month mortality rate of the 53 patients was 28%.Conclusion Parameters of oxygenation and radiological score could be associated with this transfer on day 1 of the onset of pneumonia occurrence. A further study should evaluate an earlier selection of this type of patient, followed by an early admission to the MICU, in order to improve ICU outcome.