Predictive effect of net water uptake on futile recanalisation in patients with acute large-vessel occlusion stroke

AIM

To determine whether net water uptake (NWU) based on automated software evaluation could predict futile recanalisation in patients with acute anterior circulation large-vessel occlusion (LVO).

MATERIALS AND METHODS

Patients with acute anterior circulation LVO undergoing mechanical thrombectomy in Jinling Hospital were evaluated retrospectively. NWU and other baseline data were evaluated by performing univariate and multivariate analyses. The primary endpoint was 90-day modified Rankin scale score ≥3. A nomogram to predict poor clinical outcomes was developed based on multivariate logistic regression analysis.

RESULTS

Overall, 135 patients who underwent thrombectomy with a TICI grade ≥2b were enrolled. In multivariate logistic regression analysis, the following factors were identified as independent predictors of futile recanalisation: age (odds ratio [OR]: 1.055, 95 % confidence interval [CI]: 1.004-1.110, p=0.035), female (OR: 0.289, 95 % CI: 0.098-0.850, p=0.024), hypertension (OR: 3.182, 95 % CI: 1.160-8.728, p=0.025), high blood glucose level (OR: 1.36, 95 % CI: 1.087-1.701, p=0.007), admission National Institutes of Health Stroke Scale score (OR: 1.082, 95 % CI: 1.003-1.168, p=0.043), and NWU (OR: 1.312, 95 % CI: 1.038-1.659, p=0.023).

CONCLUSIONS

NWU based on Alberta Stroke Program Early Computed Tomography (CT) Score (ASPECTS) could be used to predict the occurrence of futile recanalisation in patients with acute anterior circulation LVO ischaemic stroke.

Utility of Circulating Tumor DNA Assessment in Characterizing Recurrence Sites after Optimal Resection for Metastatic Colorectal Cancer

INTRODUCTION

Plasma ctDNA is a promising biomarker for metastatic colorectal cancer (mCRC); however, its role in characterizing recurrence sites after mCRC resection remains poorly understood. This single-institution study investigated the timing of ctDNA detection and its levels in the context of recurrence at different sites following mCRC resection.

METHODS

Patients who underwent optimal resection of CRC metastases involving the peritoneum, distant lymph nodes, or liver, with serial postoperative tumor-informed ctDNA assessments (Signatera) were included. Recurrence sites, as defined by surveillance imaging or laparoscopy, were categorized as peritoneal-only and other distant sites (liver, lung, lymph nodes, or body wall).

RESULTS

Among the 31 included patients, ctDNA was detected in all 26 (83.4%) patients with postoperative recurrence and was persistently undetectable in five patients who did not experience recurrence. At three months post-surgery, ctDNA was detected in 2/8 (25.0%) patients with peritoneal-only recurrence and 17/18 (94.4%) patients with distant recurrence (p < 0.001). Beyond three months, ctDNA was detected in the remaining six patients with peritoneal-only disease and one patient with distant disease. ctDNA detection preceded the clinical diagnosis of recurrence by a median of nine weeks in both groups. At recurrence, peritoneal-only recurrent cases exhibited lower ctDNA levels (median 0.4 MTM/ml, IQR 0.1-0.8) compared to distant recurrence (median 5.5 MTM/ml, IQR 0.8-33.3, p = 0.004).

CONCLUSION

Peritoneal-only recurrence was associated with delayed ctDNA detection and low levels of ctDNA after optimal resection for mCRC. ctDNA testing may effectively characterize recurrence sites and may help guide subsequent treatments specific to the disease sites involved.

Activation of Endothelial Large Conductance Potassium Channels Protects against TNF-α-Induced Inflammation

Elevated TNF-α levels in serum and broncho-alveolar lavage fluid of acute lung injury patients correlate with mortality rates. We hypothesized that pharmacological plasma membrane potential (Em) hyperpolarization protects against TNF-α-induced CCL-2 and IL-6 secretion from human pulmonary endothelial cells through inhibition of inflammatory Ca2+-dependent MAPK pathways. Since the role of Ca2+ influx in TNF-α-mediated inflammation remains poorly understood, we explored the role of L-type voltage-gated Ca2+ (CaV) channels in TNF-α-induced CCL-2 and IL-6 secretion from human pulmonary endothelial cells. The CaV channel blocker, Nifedipine, decreased both CCL-2 and IL-6 secretion, suggesting that a fraction of CaV channels is open at the significantly depolarized resting Em of human microvascular pulmonary endothelial cells (-6 ± 1.9 mV), as shown by whole-cell patch-clamp measurements. To further explore the role of CaV channels in cytokine secretion, we demonstrated that the beneficial effects of Nifedipine could also be achieved by Em hyperpolarization via the pharmacological activation of large conductance K+ (BK) channels with NS1619, which elicited a similar decrease in CCL-2 but not IL-6 secretion. Using functional gene enrichment analysis tools, we predicted and validated that known Ca2+-dependent kinases, JNK-1/2 and p38, are the most likely pathways to mediate the decrease in CCL-2 secretion.

BK Channels Regulate LPS-induced CCL-2 Release from Human Pulmonary Endothelial Cells

We recently established a role for the stretch-activated two-pore-domain K+ (K2P) channel TREK-1 (K2P2.1) in inflammatory cytokine secretion using models of hyperoxia-, mechanical stretch-, and TNF-α-induced acute lung injury. We have now discovered the expression of large conductance, Ca2+-activated K+ (BK) channels in human pulmonary microvascular endothelial cells and primary human alveolar epithelial cells using semiquantitative real-time PCR, IP and Western blot, and investigated their role in inflammatory cytokine secretion using an LPS-induced acute lung injury model. As expected, LPS induced IL-6 and CCL-2 secretion from pulmonary endothelial and epithelial cells. BK activation with NS1619 decreased LPS-induced CCL-2 but not IL-6 secretion from endothelial cells and had no effect on epithelial cells, although fluorometric assays revealed that BK activation hyperpolarized the plasma membrane potential (Em) of both cell types. Interestingly, BK inhibition (Paxilline) did not alter cytokine secretion or the Em in either cell type. Furthermore, LPS treatment by itself did not affect the Em or intracellular Ca2+ concentrations. Therefore, we propose BK channel activation as a novel targeted approach to counteract LPS-induced CCL-2 secretion from endothelial cells. This protective effect appears to occur via Em hyperpolarization but independent of intracellular Ca2+ concentrations.

MPRAD: A Monte Carlo and ray-tracing code for the proton radiography in high-energy-density plasma experiments

Proton radiography is used in various high-energy-density (HED) plasma experiments. In this paper, we describe a Monte Carlo and ray-tracing simulation tool called multimegaelectronvolt proton radiography (MPRAD) that can be used for modeling the deflection of proton beams in arbitrary three dimensional electromagnetic fields as well as the diffusion of the proton beams by Coulomb scattering and stopping power. The Coulomb scattering and stopping power models in cold matter and fully ionized plasma are combined using interpolation. We discuss the application of MPRAD in a few setups relevant to HED plasma experiments where the plasma density can play a role in diffusing the proton beams and affecting the prediction and interpretation of the proton images. It is shown how the diffusion due to plasma density can affect the resolution and dynamical range of the proton radiography.

A nonmyeloablative chimeric mouse model accurately defines microglia and macrophage contribution in glioma

Aims

Resident and peripherally derived glioma associated microglia/macrophages (GAMM) play a key role in driving tumour progression, angiogenesis, invasion and attenuating host immune responses. Differentiating these cells’ origins is challenging and current preclinical models such as irradiation‐based adoptive transfer, parabiosis and transgenic mice have limitations. We aimed to develop a novel nonmyeloablative transplantation (NMT) mouse model that permits high levels of peripheral chimerism without blood‐brain barrier (BBB) damage or brain infiltration prior to tumour implantation.

Methods

NMT dosing was determined in C57BL/6J or Pep3/CD45.1 mice conditioned with concentrations of busulfan ranging from 25 mg/kg to 125 mg/kg. Donor haematopoietic cells labelled with eGFP or CD45.2 were injected via tail vein. Donor chimerism was measured in peripheral blood, bone marrow and spleen using flow cytometry. BBB integrity was assessed with anti‐IgG and anti‐fibrinogen antibodies. Immunocompetent chimerised animals were orthotopically implanted with murine glioma GL‐261 cells. Central and peripheral cell contributions were assessed using immunohistochemistry and flow cytometry. GAMM subpopulation analysis of peripheral cells was performed using Ly6C/MHCII/MerTK/CD64.

Results

NMT achieves >80% haematopoietic chimerism by 12 weeks without BBB damage and normal life span. Bone marrow derived cells (BMDC) and peripheral macrophages accounted for approximately 45% of the GAMM population in GL‐261 implanted tumours. Existing markers such as CD45 high/low proved inaccurate to determine central and peripheral populations while Ly6C/MHCII/MerTK/CD64 reliably differentiated GAMM subpopulations in chimerised and unchimerised mice.

Conclusion

NMT is a powerful method for dissecting tumour microglia and macrophage subpopulations and can guide further investigation of BMDC subsets in glioma and neuro‐inflammatory diseases.

The effect of a distributed mass loading on the frequency response of a MEMS mesh resonator

This paper reports on the development of an acoustic-wave biosensor based on integrated MEMS technology that promises high sensitivity and selectively without the need for molecular tagging or external optical equipment. The device works by detecting frequency shifts resulting from the selective binding of target molecules to the surface of a functionalized resonating polymer MEMS-composite membrane. Here, we characterize the frequency response of our metal-oxide MEMS resonators. We show that the structural topology, which includes the amount of void area spacing, total mass of the resonator, and how the mass is distributed on the surface, affects the resonant frequency response in a measurable way. Using a multimodal electrostatic drive, we can either excite or suppress higher order harmonic frequencies. The excitation of higher order harmonics is important for multiple analyte detection or redundancy testing. We use a finite element model to demonstrate how a distributed mass loading affect the frequency responses of our MEMS structures.

One-stop clinic for assessment of risk for trisomy 21 at 11-14 weeks: a prospective study of 15 030 pregnancies

OBJECTIVE

To evaluate the performance of a one-stop clinic for assessment of risk (OSCAR) for trisomy 21 by a combination of maternal age, fetal nuchal translucency (NT) thickness and maternal serum free beta-human chorionic gonadotropin (hCG) and pregnancy-associated plasma protein-A (PAPP-A) at 11-14 weeks of gestation.

METHOD

Screening for trisomy 21 was carried out by OSCAR in 15 030 singleton pregnancies with live fetuses at 11-14 weeks. The estimated risk for trisomy 21 was calculated, and the women were counseled regarding this risk and the option of invasive testing or expectant management. Follow-up of the outcome of all pregnancies was carried out. The detection and false-positive rates for different risk cut-offs were calculated.

RESULTS

Fetal NT and maternal serum free beta-hCG and PAPP-A were successfully measured in all cases. Pregnancy outcome, including karyotype results or the birth of a phenotypically normal baby, was obtained from 14 383 cases. The median maternal age of these cases was 34 (range 15-49) years and in 6768 (47.1%) the age was 35 years or greater. The median gestation at screening was 12 (range 11-14) weeks and the median fetal crown-rump length was 64 (range 45-84) mm. The estimated risk for trisomy 21 based on maternal age, fetal NT and maternal serum free beta-hCG and PAPP-A was 1 in 300 or greater in 6.8% (967 of 14 240) normal pregnancies, in 91.5% (75 of 82) of those with trisomy 21 and in 88.5% (54 of 61) of those with other chromosomal defects. For a fixed false-positive rate of 5% the respective detection rates of screening for trisomy 21 by maternal age alone, maternal age and serum free beta-hCG and PAPP-A, maternal age and fetal NT, and by maternal age, fetal NT and maternal serum biochemistry were 30.5%, 59.8%, 79.3% and 90.2%, respectively.

CONCLUSION

Screening for trisomy 21 by a combination of maternal age, fetal NT and maternal serum biochemistry at 11-14 weeks can be provided in an OSCAR setting and is associated with a detection rate of about 90% for a false-positive rate of 5%.

Lack of association of presenilin-1 intron-8 polymorphism with neuropathological features of Alzheimer's disease

Over 45 mutations within the coding region of presenilin-1 (PS-1) are associated with an autosomal dominant form of Alzheimer's disease. Recently allele 1 of a polymorphism within intron-8 was reported to be in disequilibrium with Alzheimer's disease in a group of patients with sporadic Alzheimer's disease. This association has been replicated in some, but not all, studies. To determine whether the PS-1 intronic polymorphism is overrepresented in Alzheimer's disease in an autopsy-proven series, and to examine whether allele 1 is associated with a specific neuropathological phenotype, polymerase chain reaction based technique was used to assess the genotype in 85 cases of Alzheimer's disease. The resulting genotypes were compared with age of onset, duration of illness, and quantitative neuropathological measures of Abeta(total), Abeta(1-40), Abeta(1-42), neurofibrillary tangle number and neuron number. The 1/1 genotype did not associate with any differences in the clinical or neuropathological phenotype. These data suggest that the PS-1 intron-8 polymorphism does not strongly impact the clinical or neuropathologic features of Alzheimer's disease.

Genetic association of an alpha2-macroglobulin (Val1000lle) polymorphism and Alzheimer's disease

alpha2-Macroglobulin (A2M) is a proteinase inhibitor found in association with senile plaques (SP) in Alzheimer's disease (AD). A2M has been implicated biochemically in binding and degradation of the amyloid beta (Abeta) protein which accumulates in SP. We studied the relationship between Alzheimer's disease and a common A2M polymorphism, Val1000 (GTC)/Ile1000 (ATC), which occurs near the thiolester active site of the molecule. In an initial exploratory data set (90 controls and 171 Alzheimer's disease) we noted an increased frequency of the G/G genotype from 0.07 to 0.12. We therefore tested the hypothesis that the G/G genotype is over-represented in Alzheimer's disease in an additional independent data set: a group of 359 controls and 566 Alzheimer's disease patients. In the hypothesis testing cohort, the G/G genotype increased from 0.07 in controls to 0.12 in Alzheimer's disease (P < 0.05, Fisher's exact test). The odds ratio for Alzheimer's disease associated with the G/G genotype was 1.77 (1.16-2.70, P < 0.01) and in combination with APOE4 was 9.68 (95% CI 3.91-24.0, P < 0.001). The presence of the G allele was associated with an increase in Abeta burden in a small series. The A2M receptor, A2M-r/LRP, is a multifunctional receptor whose ligands include apolipoprotein E and the amyloid precursor protein. These four proteins have each been genetically linked to Alzheimer's disease, suggesting that they may participate in a common disease pathway.

Lack of specific association of presenilin 1 (PS-1) protein with plaques and tangles in Alzheimer's disease

Missense mutations in the presenilin-1 (PS-1) gene are causally related to the majority of familial early-onset Alzheimer's disease (FAD). PS-1 immunohistochemical expression in normal human brain and in brains with Alzheimer's disease (AD) has so far been controversial. Here, we report a study of PS-1 expression in brains, cell lines and peripheral blood mononuclear cells using a panel of well characterized PS-1-specific antibodies. These antibodies were characterized by immunofluorescent staining of PS-1 transfectants followed by flow cytometric analysis. In human brain, widespread neuronal staining was observed. PS-1 immunoreactivity was primarily confined to neuronal cell bodies and proximal dendrites. Weaker staining of microglia was also detected, in accord with the finding of PS-1 immunoreactivity in monocytes. PS-1 expression is not particularly associated with neurons either containing or spared from neurofibrillary tangles, nor with senile plaques. The level of PS-1 expression does not differ between normal and AD brains. Immunoprecipitation from AD, FAD and control brains revealed only a 32 kDa N-terminal fragment and an 18-20 kDa C-terminal fragment. Little or no full length PS-1 was detected. The enriched presence of PS-1 in neurons implies an important role in neuronal function, however, the lack of apparent association of its expression with AD pathology signifies the need for a better understanding of its pathophysiological role.

Association of apolipoprotein E epsilon2 and vasculopathy in cerebral amyloid angiopathy

OBJECTIVE

Hemorrhage related to cerebral amyloid angiopathy (CAA) appears to occur through a multistep pathway that includes deposition of beta-amyloid in cerebral vessels and specific vasculopathic changes in the amyloid-laden vessels, such as cracking of the vessel wall. Recent reports suggest a positive association between CAA-related hemorrhage and both the apolipoprotein E (APOE) epsilon4 allele and, unexpectedly, the APOE epsilon2 allele. Unlike APOE epsilon4, APOE epsilon2 does not appear to act through increased beta-amyloid deposition. We therefore sought to determine whether it might specifically accelerate the second step in this pathway, that is, development of the vasculopathic changes that lead to hemorrhage.

METHODS

To determine the role of APOE in development of vasculopathic changes, we compared APOE genotypes in two groups of postmortem brains: 52 brains with complete amyloid replacement of vessel walls but without vasculopathic changes, and 23 brains with complete amyloid replacement of vessels with the accompanying changes of cracking of the vessel wall and paravascular leaking of blood.

RESULTS

Frequency of APOE epsilon2 was significantly greater in the group with vasculopathy (0.09) than the group without (0.01, p = 0.03). The groups did not differ in mean age or extent of neuritic plaques. Analysis of a clinical series of patients with CAA-related hemorrhage confirmed an overrepresentation of APOE epsilon2 as well as an association between this allele and earlier age of first hemorrhage.

CONCLUSIONS

These data suggest that APOE epsilon2 and epsilon4 might promote CAA-related hemorrhage through separate mechanisms: epsilon4 by enhancing amyloid deposition and epsilon2 by causing amyloid-laden vessels to undergo the vasculopathic changes that lead to rupture.

Characterization of xenobiotic-metabolizing enzymes and nitrosamine metabolism in the human esophagus

Esophageal cancer has been associated with tobacco smoking, and nitrosamines are possible causative agents for this cancer. The present study investigated the metabolism of the tobacco carcinogens N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), and N-nitrosodimethylamine (NDMA), as well as the presence of xenobiotic-metabolizing enzymes in human esophageal tissues from individuals in the United States and Huixian, Henan Province, China (a high-risk area for esophageal cancer). All esophageal microsomal samples activated NNN and the metabolic rate was 2-fold higher in the esophageal samples from China than the USA. All microsomal samples activated NDMA. However, most of the microsomal samples did not activate NNK. Troleandomycin (an inhibitor of cytochrome P450 3A) decreased the formation of NNN-derived keto acid by 20-26% in the esophageal microsomes. The activities for NADPH: cytochrome c reductase, ethoxycoumarin O-deethylase, NAD(P)H: quinone oxidoreductase and glutathione S-transferase were present in the esophageal samples. Coumarin 7-hydroxylase (a representative activity for P450 2A6) activity was not detected in the esophageal microsomal samples. The activities for nitrosamine metabolism and xenobiotic-metabolizing enzymes were decreased (by 30-50%) in the squamous cell carcinomas compared with their corresponding non-cancerous mucosa. The presence of activation and detoxification enzymes in the esophagus may play an important role in determining the susceptibility of the esophagus to the carcinogenic effect of nitrosamines. Our results suggest that P450s 3A4 and 2E1 are involved in the activation of NNN and NDMA, respectively, in the human esophagus.

[Clinical applications of island and myocutaneous flaps]

OBJECTIVE

This is to introduce the experience in clinical applications of the island and myocutaneous flaps.

METHODS

Since 1985 fifteen types of vascularized island and myocutaneous flaps have been applied in 52 cases (21 positions) for the following purposes: repairing traumatic soft tissue defects on the limb, scar contracture, congenital recto-vaginal fistula, reconstructing congenital nasal deformity and rehabilitating function. The non-major artery island flap was used in 47 cases (90.38%) and the retrograde island flap was used in 24 cases (46.15%). The size of the flap ranged from 2.5 cm x 1.5 cm to 15 cm x 12 cm.

RESULTS

All the flaps survived with primary healing. Follow-up for 8 months to 11 years showed aesthetically and functionally satisfactory results in all cases.

CONCLUSION

These island and myocutaneous flaps have rich blood supply and are highly anti-infective. The operation is easy and the success rate is high.

A large adrenal pseudocyst mimicking malignant intraabdominal tumor: a case report

An abdominal mass was found in an apparently healthy 66-year-old man during he was undergoing a routine physical check-up. Intravenous pyelography showed a huge suprarenal cyst displacing the left kidney. Both kidneys had normal renal function. The tumor was removed transperitoneally. It contained 1600 ml hemorrhagic fluid and had small golden nodules on the inner cystic surface. Microscopically, adrenal cortical tissue was present in groups or scattered along the cystic wall, which was compatible with the diagnosis of pseudocyst. No lining epithelium was present. The differential diagnosis, pathogenesis, management, and the general features of adrenal pseudocysts were discussed.

Association between plasma high density lipoprotein cholesterol and antipyrine metabolism in alcoholics

Seven patients entering an alcoholic detoxification and treatment unit exhibited elevated levels of plasma high density lipoprotein cholesterol (HDLC) and enhanced metabolic disposal of antipyrine. Following a 2-week abstinence treatment, the HDLC levels were reduced by 28% (from 64 to 47 mg/100 ml) and the t 1/2 of antipyrine was extended from 12.4 to 13.7 hours. The extent of the HDLC reduction correlated with the antipyrine t 1/2 changes (r = -0.753, P = 0.05).