Efficacy, toxicities, and prognostic factors of stereotactic body radiotherapy for unresectable liver metastases.

INTRODUCTION: This study aims to determine the outcomes of stereotactic body radiotherapy (SBRT) for liver metastases in patients not eligible for surgery. METHODS: This study included 31 consecutive patients with unresectable liver metastases who received SBRT between January 2012 and December 2017; 22 patients had primary colorectal cancer and nine patients had primary non-colorectal cancer. Treatments ranged from 24 Gy to 48 Gy in 3 to 6 fractions over 1 to 2 weeks. Survival, response rates, toxicities, clinical characteristics, and dosimetric parameters were evaluated. Multivariate analysis was performed to identify significant prognostic factors for survival. RESULTS: Among these 31 patients, 65% had received at least one prior regimen of systemic therapy for metastatic disease, whereas 29% had received chemotherapy for disease progression or immediately after SBRT. The median follow-up interval was 18.9 months; actuarial in-field local control rates at 1, 2, and 3 years after SBRT were 94%, 55%, and 42%, respectively. The median survival duration was 32.9 months; 1-year, 2-year, and 3-year actuarial survival rates were 89.6%, 57.1%, and 46.2%, respectively. The median time to progression was 10.9 months. Stereotactic body radiotherapy was well-tolerated, with grade 1 toxicities of fatigue (19%) and nausea (10%). Patients who received post-SBRT chemotherapy had significant longer overall survival (P=0.039 for all patients and P=0.001 for patients with primary colorectal cancer). CONCLUSION: Stereotactic body radiotherapy can be safely administered to patients with unresectable liver metastases, and it may delay the need for chemotherapy. This treatment should be considered for selected patients with unresectable liver metastases.

The view of Hong Kong parents on secondary use of dried blood spots in newborn screening program.

BACKGROUND: Residual dried blood spots (rDBS) from newborn screening programmes represent a valuable resource for medical research, from basic sciences, through clinical to public health. In Hong Kong, there is no legislation for biobanking. Parents' view on the retention and use of residual newborn blood samples could be cultural-specific and is important to consider for biobanking of rDBS. OBJECTIVE: To study the views and concerns on long-term storage and secondary use of rDBS from newborn screening programmes among Hong Kong Chinese parents. METHODS: A mixed-method approach was used to study the views and concerns on long-term storage and secondary use of rDBS from newborn screening programmes among Hong Kong Chinese parents of children 0-3 years or expecting parents through focus groups (8 groups; 33 participants) and a survey (n = 1012, 85% mothers) designed with insights obtained from the focus groups. We used framework analysis to summarise the themes as supportive factors, concerns and critical arguments for retention and secondary use of rDBS from focus group discussion. We used multiple logistic regression to assess factors associated with support for retention and secondary use of rDBS in the survey. RESULTS: Both in focus groups and survey, majority of parents were not aware of the potential secondary use of rDBS. Overall secondary use of rDBS in medical research was well accepted by a large proportion of Hong Kong parents, even if all potential future research could not be specified in a broad consent. However parents were concerned about potential risks of biobanking rDBS including leaking of data and mis-use of genetic information. Parents wanted to be asked for permission before rDBS are stored and mainly did not accept an "opt-out" approach. The survey showed that parents born in mainland China, compared to Hong Kong born parents, had lower awareness of newborn screening but higher support in biobanking rDBS. Higher education was associated with support in rDBS biobanking only among fathers. CONCLUSION: Long-term storage and secondary use of rDBS from newborn screening for biomedical research and a broad consent for biobanking of rDBS are generally acceptable to Hong Kong parents given their autonomy is respected and their privacy is protected, highlighting the importance of an accountable governance and a transparent access policy for rDBS biobanks.

Merkel cell carcinoma in Taiwan: A rare tumour with a better prognosis in those harbouring Merkel cell polyomavirus.

Merkel cell carcinoma (MCC) is a rare malignant cutaneous neuroendocrine tumour affecting mainly elderly patients and is more common in the West than in Asia. It is associated with Merkel cell polyomavirus (MCPyV), immunosuppression, and ultraviolet light. In this study, we retrospectively investigated the first series of MCC from Taiwan and identified 19 cases from three tertiary centres. All patients were males with a median age of 67.5. Twelve (63%) cases occurred in the extremities, with one unique case presenting initially as nodal metastasis of unknown primary. Immunohistochemically, the great majority of tumours expressed CK20 (89%), synaptophysin (89%), and INSM1 (84%), with none positive for TTF1. Eleven (58%) cases were positive for MCPyV by immunohistochemistry (clone CM2B4). All patients were treated with excision, including four with additional radiotherapy and one with radiotherapy and chemotherapy. Nodal status and treatment modalities significantly affected survival. The median survival time of MCPyV-positive cases was much longer than the negative cases (median 40 vs. 10 months). In summary, we presented the first report on the clinicopathological features of MCC in Taiwan, with 58% cases associated with MCPyV. The prognosis of patients with MCPyV-positive tumours was better than those negative for MCPyV.

Effect of compression fracture on trabecular bone score at lumbar spine.

Bone mineral density (BMD) may be increased due to vertebral compression fractures (VCF). Our study showed trabecular bone scores (TBS) was less affected than BMD by fractured vertebrae. The TBS of most compression fractures, including old and recent VCF with mild or moderate deformity and old VCF with severe deformity, could still be used in predicting fracture risk. INTRODUCTION: Trabecular bone score (TBS), a noninvasive tool estimating bone microarchitecture, provides complementary information to lumbar spine bone mineral density (BMD). Lumbar spine BMD might be increased due to both degenerative disease and vertebral compression fractures (VCF). Lumbar spine TBS has been confirmed not influenced by osteoarthrosis, but the effects of VCF are still not been well evaluated. This study aimed to investigate whether lumbar spine TBS was affected by fractured vertebrae. METHODS: We studied postmenopausal women and men above 50 years old who underwent DXA between January 1, 2017, and May 31, 2019. By calculating the difference of BMD and TBS between L1 and the mean of L2-3, the study compared the difference of values between the control group and fracture group to determine the effects of fractured vertebrae on BMD and TBS. RESULTS: A total of 377 participants were enrolled with 202 in the control group (157 females; age: 68.06 ± 6.47 years) and 175 in the fracture group (147 females; age: 71.71 ± 9.44 years). The mean BMD of the L1 vertebrae in the fracture group was significantly higher than that in the control group (p < 0.0001). There was no significant difference between the mean differences of TBS between L1 and the means of L2-3 vertebrae in the control group and the most compression fractures, including old and recent VCF with mild or moderate deformity and old VCF with severe deformity. CONCLUSION: Lumbar spine TBS, unlike BMD, is less affected by fractured vertebrae. The TBS of most compression fractures, including old and recent VCF with mild or moderate deformity and old VCF with severe deformity, could still be used in predicting fracture risk.

Probing negatively charged and neutral excitons in MoS2/hBN and hBN/MoS2/hBN van der Waals heterostructures.

High-quality van der Waals heterostructures assembled from hBN-encapsulated monolayer transition metal dichalcogenides enable observations of subtle optical and spin-valley properties whose identification was beyond the reach of structures exfoliated directly on standard SiO2/Si substrates. Here, we describe different van der Waals heterostructures based on uncapped single-layer MoS2 stacked onto hBN layers of different thicknesses and hBN-encapsulated monolayers. Depending on the doping level, they reveal the fine structure of excitonic complexes, i.e. neutral and charged excitons. In the emission spectra of a particular MoS2/hBN heterostructure without an hBN cap we resolve two trion peaks, T1 and T2, energetically split by about 10 meV, resembling the pair of singlet and triplet trion peaks (T S and T T ) in tungsten-based materials. The existence of these trion features suggests that monolayer MoS2 has a dark excitonic ground state, despite having a 'bright' single-particle arrangement of spin-polarized conduction bands. In addition, we show that the effective excitonic g-factor significantly depends on the electron concentration and reaches the lowest value of -2.47 for hBN-encapsulated structures, which reveals a nearly neutral doping regime. In the uncapped MoS2 structures, the excitonic g-factor varies from -1.15 to -1.39 depending on the thickness of the bottom hBN layer and decreases as a function of rising temperature.

Bronchiolitis obliterans organizing pneumonia following nitric acid fume exposure.

We describe a patient with clinical, radiological and pathological features of bronchiolitis obliterans organizing pneumonia. Investigation showed that this was likely to have been a delayed consequence of inhalation of nitric acid fumes (containing nitrogen dioxide) after a fire. This case shows that thorough investigation of the aetiology is important not only in clinical management but also in ensuring patients benefit from appropriate work injury compensation.

Factors in rehospitalisation for severe pressure ulcer care in spinal cord injury/disorders.

OBJECTIVE: Repeated hospital admissions (RHA) for ongoing pressure ulcer (PU) care remains a significant challenge in the clinical management of the spinal cord injury/disorders (SCI/D) population. The current study investigated the significance of risk factors for PU treatment and RHA. METHOD: A retrospective chart review of veterans admitted to the Louis Stokes Cleveland Department of Veterans Affairs Medical Center (LSCDVAMC) Spinal Cord Injury (SCI) unit for Category III or IV PUs was carried out. A random sample of 105 individuals with SCI/D, evaluated by the Wound Care Team (WCT) from 2006 to 2009 was assessed. Multiple PU development risk factors were extracted from the electronic health record system using standardised data collection forms and entered into the Spinal Cord Injury Pressure Ulcer Database (SCIPUD). Potential associations with RHA were analysed. RESULTS: Twenty variables were initially identified as potentially related to PU development. Descriptive statistics and statistically significant associations between risk factors and RHA were determined. Demographic factors showed no significant association with RHA. Duration of injury, power wheelchair use and sub-optimally managed spasticity (SMS) were significantly associated with higher RHA. Sub-optimally managed neurogenic bowel (SMNB) at admission was significantly associated with reduced RHA. CONCLUSION: Factors previously found to be predictive of initial PU development may not, in fact, be predictive of RHA. Some protective trends were observed, such as polypharmacy and marital status, but these did not reach statistical significance in this preliminary study of admission characteristics, warranting further research. DECLARATION OF INTEREST: There were no external sources of funding for this study. The authors have no conflicts of interests to declare.

Repeatability and clinical utility in stereophotogrammetric measurements of wounds.

OBJECTIVE: To investigate the hypothesis that stereophotogrammetric wound size monitoring shows suitable inter-observer reliability and user acceptance for clinical practice use. METHOD: Veterans admitted for conservative management of severe pressure ulcers were eligible for inclusion in the study. Three-dimensional (3D) digital wound images were independently captured by two expert and two non-expert nurse-observers using a commercially available stereophotogrammetry system,weekly for 6 weeks.A double-blinded analyst generated 3D wound reconstructions, using software to determine geometry. Clinical opinion of wound progression was provided by an expert physician. RESULTS: Thirteen wounds were assessed with more than 80% of all images being readable. Interclass correlation of 0.9867 (p < 0.000 I) was observed. Compared with clinical opinion, 3D wound measurement was sensitive between improving and static wounds for wound perimeter, volume, depth and length. CONCLUSION: These preliminary findings suggest that 3D wound measurement minimises differences in wound measurement between expert and non-expert observers, suggesting it could be implemented with high reliability in health-care settings where several observers are involved in wound care management.

Polymer functionalized ZnO nanobelts as oxygen sensors with a significant response enhancement.

A plasma-polymerized acrylonitrile (PP-AN)/ZnO nanobelt (NB) nanosensor reveals a better oxygen-sensing response than a bare ZnO NB nanosensor due to the sorption nature of the polymer. With the aid of UV light, significant response enhancements of PP-AN/ZnO NB nanosensors at low temperature have been observed since the effects of oxygen desorption/adsorption in PP-AN on the electron depletion region in the ZnO are significant. The minimum sensitivity at 150 degrees C is 16.6 ppm. This work permits its feasibility in areas where it is impossible to work at higher temperatures since lowering the working temperature of the sensor can avoid the structural deterioration, causing instability in the response.

Grayanotoxin poisoning from Rhododendron simsii in an infant.

We report a case of severe poisoning in a 57-day-old infant who presented with vomiting, convulsions, and shock after ingesting a bottle of milk containing a decoction of Rhododendron simsii. The grandmother collected this toxic plant from a cultivated area, believing it was good for the airways. Grayanotoxin was detected in both the urine and plant specimens. The infant made a good recovery after requiring ventilatory support for 2 days. Rhododendron is a common gardening shrub in Hong Kong. Some Rhododendron species are poisonous and contain grayanotoxin. Intentional or accidental ingestion of toxic plants can be severe or even life-threatening. It is therefore essential that clinicians be familiar with local toxic plant species.

Fibroblasts contracting collagen matrices form transient plasma membrane passages through which the cells take up fluorescein isothiocyanate-dextran and Ca2+.

When fibroblasts contract collagen matrices, the cells activate a Ca(2+)-dependent cyclic AMP signaling pathway. We have found that contraction also stimulates uptake of fluorescein isothiocyanate-dextran molecules from the medium. Our results indicate that fluorescein isothiocyanate-dextran enters directly into the cell cytoplasm through 3- to 5-nm plasma membrane passages. These passages, which reseal in less than 5 s in the presence of divalent cations, also are likely sites of Ca2+ uptake during contraction and the first step in contraction-activated cyclic AMP signaling. The formation of plasma membrane passages during fibroblast contraction may reflect a general cellular response to rapid mechanical changes.

Increased Vasoocclusive Crises in "O" Blood Group Sickle Cell Disease Patients: Association with Underlying Thrombospondin Levels.

OBJECTIVES: To explore the incidence of vaso-occlusive crisis (VOC) in Blood Group "O" sickle cell disease (SCD) patients, and correlate it with the blood group and thrombospondin (TSP) levels. METHODS: In 89 consecutive SCD patients, blood samples were obtained for von Williebrand factor (vWF:Ag) antigen, collagen binding activity (CBA), ristocetin binding activity (RCo), blood group typing, C-reactive protein (CRP), high performance liquid chromatography (HPLC), Serum TSP 1 and TSP 2 levels, complete blood counts (CBC), lactic dehydrogenase (LDH) levels, liver function (LFT) and renal function tests (RFT) during VOC episodes and in steady state conditions. RESULTS: In steady state SCD patients (n=72), "O" blood group patients (n=37) showed a significantly higher median serum TSP 1 and TSP 2 levels as compared to non-O blood group patients [n=35] [p <0.05, Mann-Whitney test]; with an inverse relation between vWF:Ag, Factor VIII:C and TSP levels. Furthermore, the serum TSP 1 and TSP 2 levels were significantly higher in patients presenting with acute VOC [n=17], as well as in those with repeated VOC's (group 1, n=16), especially amongst blood group "O" patients [p, <0.05, Mann-Whitney test]. CONCLUSIONS: The study demonstrates an inverse relation between TSP and vWF levels, in blood group "O" SCD patients, with an upregulation of the TSP levels. Expectedly, during active VOC crisis, the TSP 1 and TSP 2 levels were significantly elevated.

Transparent Memory For Harsh Electronics.

As a new class of non-volatile memory, resistive random access memory (RRAM) offers not only superior electronic characteristics, but also advanced functionalities, such as transparency and radiation hardness. However, the environmental tolerance of RRAM is material-dependent, and therefore the materials used must be chosen carefully in order to avoid instabilities and performance degradation caused by the detrimental effects arising from environmental gases and ionizing radiation. In this work, we demonstrate that AlN-based RRAM displays excellent performance and environmental stability, with no significant degradation to the resistance ratio over a 100-cycle endurance test. Moreover, transparent RRAM (TRRAM) based on AlN also performs reliably under four different harsh environmental conditions and 2 MeV proton irradiation fluences, ranging from 1011 to 1015 cm-2. These findings not only provide a guideline for TRRAM design, but also demonstrate the promising applicability of AlN TRRAM for future transparent harsh electronics.

Production of hematopoietic regulatory cytokines by peripheral blood mononuclear cells in patients with aplastic anemia.

The aim of this study was to measure the level of cytokines produced by peripheral blood mononuclear cells (PBMNC) in patients with aplastic anemia (AA) and determine their effect on normal bone marrow (BM) colony growth. Thirty-five patients with AA and 21 normal controls were enrolled in the study. Medium conditioned by PBMNC of AA patients in the presence of phytohemagglutinin (PHA) was found to be suppressive to the clonal growth of normal BM cells. Thus, we further determined the presence in the PBMNC conditioned medium (CM) of inhibitory cytokines (macrophage inflammatory protein-1 alpha [MIP-1 alpha], transforming growth factor-beta 2 [TGF-beta 2], interferon-gamma [IFN-gamma], and tumor necrosis factor-alpha [TNF-alpha]) and stimulatory cytokines (granulocyte-macrophage colony-stimulatory factor [GM-CSF], interleukin-3 [IL-3], and stem cell factor [SCF]). The results show no significant difference between AA patients and normal controls in the spontaneous production of all cytokines by PBMNC. After PHA stimulation, the production of MIP-1 alpha, IFN-gamma, TNF-alpha, and GM-CSF significantly increased in the cultures of AA patients (p = 0.0009, 0.0002, 0.0022, and 0.0156, respectively). However, both TGF-beta 2 and SCF were undetectable in most of the tested samples. IL-3 was measured in the conditioned medium only after PHA stimulation, but without significant difference between the two groups (p = 0.67). Furthermore, the myelopoietic suppressing effect of AA-PBMNC CM could be significantly blocked by pretreatment with specific antibodies to the corresponding inhibitory cytokines (MIP-1 alpha, IFN-gamma, and TNF-alpha). After antibody neutralization, an apparent change occurred in the clonal growth of normal BM cells incubated with AA-PBMNC CM, resulting in colony enhancement of 205, 131, and 237% by anti-MIP-1 alpha, anti-IFN-gamma, and anti-TNF-alpha, respectively. These results suggest that overproduction of inhibitory cytokines, rather than underproduction of stimulating cytokines, may play a role in the progression of at least some patients with AA.

Degradation of fibronectin and vitronectin in chronic wound fluid: analysis by cell blotting, immunoblotting, and cell adhesion assays.

We used a combination of cell blotting, immunoblotting, and cell adhesion assays to analyze fibronectin and vitronectin in wound fluid from acute and chronic wounds. Acute wound fluid (e.g., suction blister fluid, mastectomy fluid) contained intact fibronectin and vitronectin as major cell adhesion proteins. In marked contrast, chronic wound fluid samples from three of 11 patients with venous stasis ulcers showed complete degradation of vitronectin and degradation of fibronectin into small molecular mass polypeptides less than 125 kDa. Three of these polypeptides--54, 93, and 125 kDa--were biologically active in promoting cell attachment and were recognized by monoclonal antibodies that bind fibronectin near the arg-gly-asp (RGD) domain. In wound fluid samples from the other eight of 11 patients, only slight degradation of vitronectin and fibronectin occurred, which resulted in a mixture of mostly intact molecules along with large fragments. Intact fibronectin in chronic wound fluid samples contained the ED-A domain, which showed that fibronectin synthesis occurred locally in the wound bed. Wound fluid containing extensively degraded vitronectin and fibronectin reversibly inhibited cell adhesion, and excess fetal bovine serum, but not purified fibronectin, neutralized the inhibitory effect. We suggest that protease activity in some chronic wounds may cause degradation of adhesion proteins and prevent cell adhesion necessary for normal wound closure.

A 450-kb contig of defensin genes on human chromosome 8p23.

Defensins are a large family of host defense peptides expressed in leukocytes and epithelia. Using P1 and BAC clones, we have determined the organization of the human alpha-defensin genes and the beta-defensin gene HDEFB1 on chromosome 8p23. From the telomere, the order of the genes (with encoded peptides in parentheses) is HDEFA5 (HD-5), HDEFA1/1A (HNP-1/3), HDEFA4 (HNP-4), HDEFA6 (HD-6), and HDEFB1 (HBD-1). These genes span a region of approximately 450kb. Genes encoding intestinal Paneth cell defensins (HDEFA5 and HDEFA6) flank the myeloid defensin gene cluster (HDEFA1, HDEFA1A, HDEFA4). Based on our previous studies, the remaining known defensin gene, HDEFB2 (HBD-2), is about 400kb centromeric to HDEFB1. This map supports the hypothesis, originally proposed because of sequence similarities, that myeloid alpha-defensin genes evolved by reduplication and divergence from Paneth cell defensin genes, and identifies regions and clones, which should be useful in the search for new defensin genes.

Fibrinolytic activity in Chinese patients with diabetes or hyperlipidemia in comparison with healthy controls.

Plasma tissue-type plasminogen activator (tPA), plasminogen activator inhibitor (PAI) and euglobulin lysis time (ELT) were determined before and after the venous occlusion test (VOT) in 3 groups of patients with mean age about 60 years: 29 diabetic patients (D group), 8 hyperlipidemic patients (H group) and 19 healthy controls (C group). In the D and H groups, the mean of morning tPA was significantly higher than that of the C group, but the means of PAI were not significantly different among the 3 groups. ELT was significantly shortened and tPA was markedly increased after the VOT in all 3 groups whereas PAI had not significantly changed. In conclusion, high tPA activity and good fibrinolytic response without significant change of PAI activity were found in the diabetic and hyperlipidemic patients, and no definite impairment of the fibrinolytic activity could be found in the Chinese patients with diabetes and hyperlipidemia. This might be one of the reasons why the Chinese has low incidence of thromboembolic diseases.

The predictive value of the hemostasis parameters in the development of preeclampsia.

In order to find out which hemostasis parameters would have the predictive value for the development of preeclampsia, modified antithrombin III (ATM, representative of the antithrombin III-serine esterase complex), tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), beta-thromboglobulin (BTG), antithrombin III (AT III), fibrinogen, fibrin(ogen) degradation product (FDP), FDP D-dimer and euglobulin lysis time (ELT) were measured in 20 normal non-pregnant women, 21 normal pregnant women, 6 high-risk pregnant women, 14 preeclampsia pregnant women, and 5 patients with disseminated intravascular coagulation (DIC). Only tPA and AT III were found significantly different between the preeclampsia and the normal or high-risk pregnant women: tPA was found progressively and significantly increased from the normal pregnant, to the high-risk pregnant, then to the preeclampsia women (p less than 0.05). AT III was significantly lower in the preeclampsia than in the normal pregnant (p = 0.0001) or in the high-risk pregnant women (p = 0.002). In the 2nd trimester, tPA, PAI, fibrinogen and FDP were significantly higher, and AT III was significantly lower in the preeclampsia than in the normal pregnant women, whereas in the 3rd trimester, tPA and AT III were significantly higher or lower, respectively, in the preeclampsia than in the normal pregnant women. No significant difference of ATM could be found between the preeclampsia and the normal or high-risk pregnant women. From the present study, we suggest that tPA and AT III would be used as the main predictors, and FDP and D-dimer as the complementary predictors for the development of preeclampsia and should be detected in the normal or high-risk pregnant women.

Effect of soluble and immobilized plasmin on fibrinogen and platelets.

Plasmin was immobilized on collageno-elastic tubes (CET) using carbodiimide as the cross-linking agent. The effects of plasmin-CET grafts and corresponding soluble plasmin on fibrinogen, thrombin-mediated fibrinogen activation, and platelet activity, were investigated. There was a significant increase in fibrinogen deposition on plasmin-CETs over non-plasmin (i.e. control) CETs. Furthermore, exposure of fibrinogen to plasmin CETs enhances its deposition to control grafts situated downstream. Plasmin-bound CETs retained higher platelet deposition when preliminarily coated with fibrinogen. Finally, plasmin exerted a positive effect on thrombin-mediated fibrinogen activation at low plasmin concentrations. A mechanistic hypothesis aimed at interpreting this finding is proposed.