Assessing the sensitivity of placental growth factor and soluble fms-like tyrosine kinase 1 at 36 weeks' gestation to predict small-for-gestational-age infants or late-onset preeclampsia: a prospective nested case-control study.

BACKGROUND: Fetal growth restriction is a disorder of placental dysfunction with three to four-fold increased risk of stillbirth. Fetal growth restriction has pathophysiological features in common with preeclampsia. We hypothesised that angiogenesis-related factors in maternal plasma, known to predict preeclampsia, may also detect fetal growth restriction at 36 weeks' gestation. We therefore set out to determine the diagnostic performance of soluble fms-like tyrosine kinase 1 (sFlt-1), placental growth factor (PlGF), and the sFlt-1:PlGF ratio, measured at 36 weeks' gestation, in identifying women who subsequently give birth to small-for-gestational-age (SGA; birthweight <10th centile) infants. We also aimed to validate the predictive performance of the analytes for late-onset preeclampsia in a large independent, prospective cohort. METHODS: A nested 1:2 case-control study was performed including 102 cases of SGA infants and a matched group of 207 controls; and 39 cases of preeclampsia. We determined the diagnostic performance of each angiogenesis-related factor, and of their ratio, to detect SGA infants or preeclampsia, for a predetermined 10% false positive rate. RESULTS: Median plasma levels of PlGF at 36 weeks' gestation were significantly lower in women who subsequently had SGA newborns (178.5 pg/ml) compared to normal birthweight controls (326.7 pg/ml, p < 0.0001). sFlt-1 was also higher among SGA cases, but this was not significant after women with concurrent preeclampsia were excluded. The sensitivity of PlGF to predict SGA infants was 28.8% for a 10% false positive rate. The sFlt-1:PlGF ratio demonstrated better sensitivity for preeclampsia than either analyte alone, detecting 69.2% of cases for a 10% false positive rate. CONCLUSIONS: Plasma PlGF at 36 weeks' gestation is significantly lower in women who subsequently deliver a SGA infant. While the sensitivity and specificity of PlGF currently limit clinical translation, our findings support a blood-based biomarker approach to detect late-onset fetal growth restriction. Thirty-six week sFlt-1:PlGF ratio predicts 69.2% of preeclampsia cases, and could be a useful screening test to triage antenatal surveillance.

Survival Difference of Colorectal Adenocarcinoma Among Racial and Ethnic Minority Groups: A SEER Database Study.

Despite advances in diagnosis and treatment, racial disparities continue to exist in colorectal cancer (CRC) survival. This study aims to characterize the CRC survival differences among racial and ethnic minority groups. The Surveillance, Epidemiology, and End Results (SEER) database was used to identify adults diagnosed with CRC from 2015 to 2019. Demographics, disease characteristics, surgical treatment, stages, and survival data for individuals who are Hispanic, Black, Southeast Asian, Chinese, American Indian and Alaskan Native (AIAN), Asian Indian and Pakistani (AIP), and Native Hawaiian and Other Pacific Islanders (NHOPI) were extracted. Survival analysis was done using the Kaplan-Meier survival curve. Multivariate analysis was done with the Cox proportional hazard model. There were 40 091 individuals with CRC. NHOPI had the youngest median age of 59 years, while Chinese individuals had the oldest median age of 65 years. From the total sample of their respective subgroups, 43.8% of Black patients and 36.7% of AIAN patients had a median household income of <$60 000, while 55.3% of Southeast Asian patients, 59.7% of Chinese patients, 55.8% of AIP patients, and 65.6% of NHOPI patient had a median household income >$70 000. The 1-year survival rate was lower for patients who were Hispanic (62.0%), Black (60.9%), and AIAN (63.1%). Even after multivariate analysis, Black patients had a significant hazard ratio (HR) of 1.21 (95% confidence interval [95% CI]: 1.05-1.38), while AIP had a HR of 0.68 (95% CI 0.55-0.84), compared to AIAN. Other significant variables that were linked with survival included older age, advanced stage of CRC, a median household income <$60 000, male sex, no surgery, subtotal colectomy/hemicolectomy, and total colectomy. Further studies are needed to elucidate the specific causes of these differences and create appropriate strategies to reduce this survival disparity.

A case report of Cronkhite-Canada syndrome first encounterd at a hospital in northern Vietnam.

Introduction and importance: Cronkhite-Canada syndrome (CCS) is an extremely rare non-inherited syndrome first described in 1955 with only about 500 more cases reported so far. Since the aetiology of the disease remains unknown, there were no specific treatments in consensus. In many countries, CCS is a completely new condition that may confuse physicians at first encounter. Lessons should be learned from these cases by gastrointestinal specialists to be aware of this condition in any circumstances. Case presentation: The authors reported a case study of a 45-year-old Vietnamese male with CCS diagnosis, which encountered at our centre for the first time. Clinical discussion: The definitive diagnosis was provided by combining clinical characteristics, and endoscopic and histopathologic features, after excluding other causes of gastrointestinal polyposis. The patient responds to corticosteroids, proton pump inhibitors, and nutritional support right after treatment. After 1 year of treatment, his symptoms ameliorated completely although colon polyps insignificantly reduced. Conclusion: Gastroenterologists should always be aware of patients with CCS with the following symptoms: gastrointestinal hamartomatous polyps, diarrhoea, and the dermatologic triad of alopecia, hyperpigmentation, and onychodystrophy.

Management of hepatocellular carcinoma in patients who are 70 years or older.

Background: Although liver transplantation has been done successfully in elderly patients with hepatocellular carcinoma, these are likely well-selected patients. This study uses a large database of patients with hepatocellular carcinoma to explore treatment and potential candidacy for liver transplantation in the elderly. Methods: Retrospective review of 1,533 hepatocellular carcinoma cases identified 2 groups: 475 patients 70 years or older (70 +) and 1,058 patients < 70 years. Demographics, risk factors, tumor characteristics, treatments, and survival were compared. Three- and 5-year survival rates were determined, and logistic regression was used to identify factors predictive of 3-year survival. Results: Patients 70 + were more likely to have metabolic factors and less likely to have viral hepatitis, cirrhosis, hepatocellular carcinoma found with surveillance (21.7% vs 28.4%, P = .005), and hepatocellular carcinoma within Milan criteria (37.3% vs 43.8%, P = .019). Model for End-stage Liver Disease score was similar, but patients 70 + had higher mean creatinine and lower mean bilirubin. Patients 70 + were equally likely to undergo liver resection but less likely to undergo liver transplantation (0.4% vs 10.2%, P < .001). Three- and 5-year survival rates were significantly worse in 70 +, and predictors of 3-year survival included hepatocellular carcinoma found with surveillance, meeting Milan criteria, and normal alpha fetoprotein. Discussion: Elderly patients with hepatocellular carcinoma were less likely to undergo liver transplantation potentially due to metabolic factors and advanced disease. Although there is no age cutoff for liver transplantation, elderly patients should be given realistic expectations of liver transplantation candidacy. Continued surveillance for hepatocellular carcinoma in elderly patients may allow for earlier diagnosis and improved liver transplantation candidacy. Key Message: Hepatocellular carcinoma in patients who are 70 years or older can be managed with liver transplantation in select cases, but more patients will be managed with liver resection and nonoperative therapies.

Facile synthesis of superparamagnetic thiamine/Fe3O4 with enhanced adsorptivity toward divalent copper ions.

The development of environmentally friendly adsorbents has been extensively carried out to overcome the detrimental effects of heavy metal accumulation, which has persistently become a global ecological problem. In pursuit of generating eco-friendly adsorbents, a green method for synthesizing thiamine functionalized-Fe3O4 (FT) was developed in this study. A one-step chemical oxidation and functionalization technique was used to prepare FT using the ammonia-containing solvent. A molar ratio of ammonia:Fe:thiamine of 15:1:1 was shown to produce FT15 with high yield, adsorptivity, and purity. XRD, XPS, FTIR, SEM, and SQUID characterization of FT15 revealed the formation of superparamagnetic thiamine functionalized Fe3O4 in their particles. This superparamagneticity facilitates the easy recovery of FT15 particles from the waste-containing solution by using an external magnetic force. The batch adsorption of Cu(II) onto FT15 showed the best fit with the Sips adsorption isotherm model with a maximum adsorption capacity of 426.076 mg g-1, which is 5.69-fold higher capacity than the control unmodified Fe3O4 (F15). After five adsorption-desorption cycles, the FT15 can maintain up to 1.95-fold higher capacity than the freshly synthesized F15. Observation on the physicochemical properties of the post-adsorption materials showed the contribution of an amine group, pyrimidine ring, and the thiazolium group of thiamine in boosting its adsorption capacity. This study provides important findings to advance the adsorptivity of magnetic adsorbents with promising recoverability from aqueous solution by employing naturally available and environmentally friendly compounds such as thiamine.

Number of degrees of freedom of two-dimensional turbulence.

We derive upper bounds for the number of degrees of freedom of two-dimensional Navier-Stokes turbulence freely decaying from a smooth initial vorticity field omega(x,y,0)=omega0. This number denoted by N is defined as the minimum dimension such that for n>or=N, arbitrary n-dimensional balls in phase space centered on the solution trajectory omega(x,y,t); for t>0, contract under the dynamics of the system linearized about omega(x,y,t). In other words, N is the minimum number of greatest Lyapunov exponents whose sum becomes negative. It is found that N

Local transfer and spectra of a diffusive field advected by large-scale incompressible flows.

This study revisits the problem of advective transfer and spectra of a diffusive scalar field in large-scale incompressible flows in the presence of a (large-scale) source. By "large scale" it is meant that the spectral support of the flows is confined to the wave-number region kkd is bounded from above by UkdkTheta(k,t) , where U denotes the maximum fluid velocity and Theta(k,t) is the spectrum of the scalar variance, defined as its average over the shell (k-kd,k+kd) . For a given flux, say vartheta>0 , across k>kd , this bound requires Theta(k,t)> or =(varthetaUkd)k(-1) . This is consistent with recent numerical studies and with Batchelor's theory that predicts a k(-1) spectrum (with a slightly different proportionality constant) for the viscous-convective range, which could be identified with (kd,kkappa) . Thus, Batchelor's formula for the variance spectrum is recovered by the present method in the form of a critical lower bound. The present result applies to a broad range of large-scale advection problems in space dimensions > or =2 , including some filter models of turbulence, for which the turbulent velocity field is advected by a smoothed version of itself. For this case, Theta(k,t) and vartheta are the kinetic energy spectrum and flux, respectively.

Melioidosis in Vietnam: Recently Improved Recognition but still an Uncertain Disease Burden after Almost a Century of Reporting.

The first cases of human melioidosis were described in Vietnam in the 1920s, almost a century ago. It was in Vietnam in the thirties that the saprophytic nature of B. pseudomallei was first recognized. Although a significant number of French and U.S. soldiers acquired the disease during the Vietnam wars, indigenous cases in the Vietnamese population were only sporadically reported over many decades. After reunification in 1975, only two retrospective studies reported relatively small numbers of indigenous cases from single tertiary care hospitals located in the biggest cities in the South and the North, respectively. Studies from provincial hospitals throughout the country were missing until the Research Network on Melioidosis and Burkholderia pseudomallei (RENOMAB) project started in 2014. From then on seminars, workshops, and national scientific conferences on melioidosis have been conducted to raise awareness among physicians and clinical laboratory staff. This led to the recognition of a significant number of cases in at least 36 hospitals in 26 provinces and cities throughout Vietnam. Although a widespread distribution of melioidosis has now been documented, there are still challenges to understand the true epidemiology of the disease. Establishment of national guidelines for diagnosis, management, and reporting of the disease together with more investigations on animal melioidosis, genomic diversity of B. pseudomallei and its environmental distribution are required.

Energy budgets in Charney-Hasegawa-Mima and surface quasigeostrophic turbulence.

We study energy transfer in unbounded Charney-Hasegawa-Mima and surface quasigeostrophic turbulence. The possible inverse-cascading quantities in these systems are, respectively, I identical with integral ( infinity )(0)k(-2)E(k) dk and J identical with integral ( infinity )(0)k(-1)E(k) dk, where E(k) is the kinetic energy spectrum. The supposed direct-cascading quantities for both surface quasigeostrophic and Navier-Stokes turbulence are shown to be bounded. We derive a constraint on E(k) for the surface quasigeostrophic system.

Robustness of the inverse cascade in two-dimensional turbulence.

We study quasisteady inverse cascades in unbounded and bounded two-dimensional turbulence driven by time-independent injection and dissipated by molecular viscosity. It is shown that an inverse cascade that carries only a fraction r of the energy input to the largest scales requires the enstrophy-range energy spectrum to be steeper than k(-5) (ruling out a direct cascade) unless 1-r<<1. A direct cascade requires the presence of an inverse cascade that carries virtually all energy to the largest scales (1-r<<1). These facts underlie the robustness of the Kolmogorov-Kraichnan k(-5/3) inverse cascade, which is readily observable in numerical simulations without an accompanying direct enstrophy cascade. We numerically demonstrate an instance where the k(-5/3) inverse-cascading range is realizable with 79% of the energy injection dissipated within the energy range and virtually all of the enstrophy dissipated in the vicinity of the forcing region. As equilibrium is approached, the respective logarithmic slopes -alpha and -beta of the ranges of wave numbers lower and higher than the forcing wave number satisfy alpha+beta approximately 8. These results are consistent with recent theoretical predictions.

Inertial-range dynamics and scaling laws of two-dimensional magnetohydrodynamic turbulence in the weak-field regime.

We study inertial-range dynamics and scaling laws in unforced two-dimensional magnetohydrodynamic turbulence in the regime of moderately small and small initial magnetic-to-kinetic-energy ratio r(0), with an emphasis on the latter. The regime of small r(0) corresponds to a relatively weak field and strong magnetic stretching, whereby the turbulence is characterized by an intense conversion of kinetic into magnetic energy (dynamo action in the three-dimensional context). This conversion is an inertial-range phenomenon and, upon becoming quasisaturated, deposits the converted energy within the inertial range rather than transferring it to the small scales. As a result, the magnetic-energy spectrum E(b)(k) in the inertial range can become quite shallow and may not be adequately explained or understood in terms of conventional cascade theories. It is demonstrated by numerical simulations at high Reynolds numbers (and unity magnetic Prandtl number) that the energetics and inertial-range scaling depend strongly on r(0). In particular, for fully developed turbulence with r(0) in the range [1/4,1/4096], E(b)(k) is found to scale as k(α), where α≳-1, including α>0. The extent of such a shallow spectrum is limited, becoming broader as r(0) is decreased. The slope α increases as r(0) is decreased, appearing to tend to +1 in the limit of small r(0). This implies equipartition of magnetic energy among the Fourier modes of the inertial range and the scaling k(-1) of the magnetic potential variance, whose flux is direct rather than inverse. This behavior of the potential resembles that of a passive scalar. However, unlike a passive scalar whose variance dissipation rate slowly vanishes in the diffusionless limit, the dissipation rate of the magnetic potential variance scales linearly with the diffusivity in that limit. Meanwhile, the kinetic-energy spectrum is relatively steep, followed by a much shallower tail due to strong antidynamo excitation. This gives rise to a total-energy spectrum poorly obeying a power-law scaling.

Bounds for the number of degrees of freedom of incompressible magnetohydrodynamic turbulence in two and three dimensions.

We study incompressible magnetohydrodynamic turbulence in both two and three dimensions, with an emphasis on the number of degrees of freedom N. This number is estimated in terms of the magnetic Prandtl number Pr, kinetic Reynolds number Re, and magnetic Reynolds number Rm. Here Re and Rm are dynamic in nature, defined in terms of the kinetic and magnetic energy dissipation rates (or averages of the velocity and magnetic field gradients), viscosity and magnetic diffusivity, and the system size. It is found that for the two-dimensional case, N satisfies N≤PrRe(3/2)+Rm(3/2) for Pr>1 and N≤Re(3/2)+Pr(-1)Rm(3/2) for Pr≤1. In three dimensions, on the other hand, N satisfies N≤(PrRe(3/2)+Rm(3/2))(3/2) for Pr>1 and N≤(Re(3/2)+Pr(-1)Rm(3/2))(3/2) for Pr≤1. In the limit Pr→0, Re(3/2) dominates Pr(-1)Rm(3/2), and the present estimate for N appropriately reduces to Re(9/4) as in the case of usual Navier-Stokes turbulence. For Pr≈1, our results imply the classical spectral scaling of the energy inertial range and dissipation wave number (in the form of upper bounds). These bounds are consistent with the existing predictions in the literature for turbulence with or without Alfvén wave effects. We discuss the possibility of solution regularity, with an emphasis on the two-dimensional case in the absence of either one or both of the dissipation terms.

Autoimmune pancreatitis in an Asian-dominant American population.

Autoimmune pancreatitis is a rare type of chronic pancreatitis that occurs predominantly in males and was first described in the Asian population. The following study seeks to characterize autoimmune pancreatitis in Hawai'i's Asian-dominant population through a retrospective review of 65 pancreaticoduodenectomy cases performed between 2000 and 2010. Three of the 65 pancreaticoduodenectomies were diagnosed with autoimmune pancreatitis, and 3 additional cases were diagnosed prior to surgery. All six patients were males and presented with obstructive jaundice, 5 with weight loss, and 4 with epigastric pain and elevated serum lipase. All six patients showed elevated serum IgG4. Imaging revealed findings typical of pancreatic malignancy: distal bile duct stricture and pancreatic head mass. However, no nodal involvement and vascular invasion were found. In conclusion, autoimmune pancreatitis should be considered in patients presenting with obstructive jaundice. Elevated serum IgG4, normal serum carbohydrate antigen CA19-9, a benign fine needle aspiration/core biopsy, and a therapeutic response to corticosteroid are typical findings of autoimmune pancreatitis. Serum IgG4 measurement is a useful tool to help differentiate autoimmune pancreatitis from most pancreatic cancers. It is important to consider autoimmune pancreatitis as a differential diagnosis of pancreatic malignancy to avoid unnecessary surgery.

Effects of friction on forced two-dimensional Navier-Stokes turbulence.

Large-scale dissipation mechanisms have been routinely employed in numerical simulations of two-dimensional turbulence to absorb energy at large scales, presumably mimicking the quasisteady picture of Kraichnan in an unbounded fluid. Here, "side effects" of such a mechanism--mechanical friction--on the small-scale dynamics of forced two-dimensional Navier-Stokes turbulence are elaborated by both theoretical and numerical analysis. Given a positive friction coefficient α, viscous dissipation of enstrophy has been known to vanish in the inviscid limit ν→0. This effectively renders the scale-neutral friction the only mechanism responsible for enstrophy dissipation in that limit. The resulting dynamical picture is that the classical enstrophy inertial range becomes a dissipation range in which the dissipation of enstrophy by friction mainly occurs. For each α>0, there exists a critical viscosity ν(c), which depends on physical parameters, separating the regimes of predominant viscous and frictional dissipation of enstrophy. It is found that ν(c)=[η'(1/3)/(Ck(f)(2))]exp[-η'(1/3)/(Cα)], where η' is half the enstrophy injection rate, k(f) is the forcing wave number, and C is a nondimensional constant (the Kraichnan-Batchelor constant). The present results have important theoretical and practical implications. Apparently, mechanical friction is a poor choice in numerical attempts to address fundamental issues concerning the direct enstrophy transfer in two-dimensional Navier-Stokes turbulence. Furthermore, as relatively strong friction naturally occurs on the surfaces and at lateral boundaries of experimental fluids as well as at the interfaces of shallow layers in geophysical fluid models, the frictional effects discussed in this study are crucial in understanding the dynamics of these systems.

Effective degrees of nonlinearity in a family of generalized models of two-dimensional turbulence.

We study the small-scale behavior of generalized two-dimensional turbulence governed by a family of model equations, in which the active scalar theta=(-Delta)(alpha/2)psi is advected by the incompressible flow u=(-psi(y),psi(x)). Here psi is the stream function, Delta is the Laplace operator, and alpha is a positive number. The dynamics of this family are characterized by the material conservation of theta, whose variance theta2 is preferentially transferred to high wave numbers (direct transfer). As this transfer proceeds to ever-smaller scales, the gradient nublatheta grows without bound. This growth is due to the stretching term (nablatheta.nabla)u whose "effective degree of nonlinearity" differs from one member of the family to another. This degree depends on the relation between the advecting flow u and the active scalar theta (i.e., on alpha) and is wide ranging, from approximately linear to highly superlinear. Linear dynamics are realized when nablau is a quantity of no smaller scales than theta, so that it is insensitive to the direct transfer of the variance of theta, which is nearly passively advected. This case corresponds to alpha>or=2 , for which the growth of nablatheta is approximately exponential in time and nonaccelerated. For alpha<2, superlinear dynamics are realized as the direct transfer of theta2 entails a growth in nablau, thereby, enhancing the production of nablatheta. This superlinearity reaches the familiar quadratic nonlinearity of three-dimensional turbulence at alpha=1 and surpasses that for alpha<1. The usual vorticity equation (alpha=2) is the border line, where nablau and theta are of the same scale, separating the linear and nonlinear regimes of the small-scale dynamics. We discuss these regimes in detail, with an emphasis on the locality of the direct transfer.