Concurrent Observation of Bulk and Protein Hydration Water by Spin-Label ESR under Nanoconfinement

Under nanoconfinement the formation of crystalline ice is suppressed, allowing the study of water dynamics at subfreezing temperatures. Here we report a temperature-dependent investigation (170–260 K) of the behavior of hydration water under nanoconfinement by ESR techniques. A 26-mer-long peptide and the Bax protein are studied. This study provides site-specific information about the different local hydrations concurrently present in the protein/peptide solution, enabling a decent comparison of the hydration moleculesthose that are buried inside, in contact with, and detached from the protein surface. Such a comparison is not possible without employing ESR under nanoconfinement. Though the confined bulk and surface hydrations behave differently, they both possess a transition similar to the reported fragile-to-strong crossover transition around 220 K. On the contrary, this transition is absent for the hydration near the buried sites of the protein. The activation energy determined under nanoconfinement is found to be lower in surface hydration than in bulk hydration. The protein structural flexibility, derived from the interspin distance distributions <i>P</i>(<i>r</i>) at different temperatures, is obtained by dipolar ESR spectroscopy. The <i>P</i>(<i>r</i>) result demonstrates that the structural flexibility is strongly correlated with the transition in the surface water, corroborating the origin of the protein dynamical transition at subfreezing temperatures

Infantile Hepatitis B in Immunized Children: Risk for Fulminant Hepatitis and Long-Term Outcomes

<div><p>Background</p><p>Infantile hepatitis B after neonatal immunoprophylaxis is a rare yet distinct disease. This study aimed to analyze the long-term outcomes and risk factors in immunized infants with hepatitis B.</p><p>Methods</p><p>The clinical parameters and outcomes of 41 infants born after universal immunization, and admitted for HBV-positive hepatitis were studied. All patients were followed for at least 6 months (median  = 4.4 years, range 0.6–18.1 years). Patient survival, changes of HBsAg and HBeAg status, and complications were analyzed.</p><p>Results</p><p>Among the 41 cases (32 males, 9 females), 21 presented with fulminant hepatitis (FH), and 20 with non-fulminant hepatitis (NFH). Ninety-five percent (36/38) of the mothers were positive for hepatitis B surface antigen (HBsAg). Multivariate analyses revealed younger age of onset (age <7 months) and negative maternal hepatitis B e antigen (HBeAg) were associated with FH (p = 0.03 and p = 0.01, respectively). An infantile fulminant hepatitis B risk score using maternal/infant HBeAg positivity and onset age was proposed. Among the FH cases, the rate of mortality, HBsAg clearance, and chronic HBV infection were 47.6%, 38.1%, and 14.3%, respectively. Among the NFH cases, 35% developed chronic infection. Of the 9 chronically infected children received long-term follow-up, 8 had HBeAg seroconversion before 4 years of age. One case of FH developed hepatocellular carcinoma 14 years later.</p><p>Conclusions</p><p>Maternal HBsAg + /HBeAg- and early onset age were risk factors for FH in immunized infants. A significant portion of patients with FH or NFH evolve to chronic HBV infection, with HBeAg seroconversion in young childhood. Close surveillance for hepatocellular carcinoma is warranted in patients surviving infantile hepatitis B.</p></div

Clinical course and outcomes of infants with hepatitis B; FH, fulminant hepatitis; NFH, non-fulminant hepatitis.

<p>Recovery is defined as HBsAg seroclearance. Chronic infection is defined as persistence of HBsAg for more than 6 months.</p

The IFHB Risk Scores in the infantile cases of hepatitis B.

<p>FH, fulminant hepatitis; NFH, non-fulminant hepatitis.</p><p>The IFHB Risk Scores in the infantile cases of hepatitis B.</p

Clinical characteristics of 41 infants with acute or fulminant hepatitis B.

<p>FH: fulminant hepatitis, NFH: non-fulminant hepatitis, HBsAg, hepatitis B surface antigen; HBeAg, hepatitis B e antigen, HBV, hepatitis B virus; HBIG, hepatitis B immunoglobulin; ALT, alanine aminotransferase; INR, international normalized ratio.</p><p>Clinical characteristics of 41 infants with acute or fulminant hepatitis B.</p

Serial data of a case of infantile fulminant hepatitis that became a chronic HBV carrier.

<p>HBsAg: hepatitis B surface antigen; anti-HBs: hepatitis B surface antibody, HBeAg: hepatitis B e antigen, anti-HBe: antibody to HBeAg, ALT: alanine aminotransferase level (dotted line), T-bil: total bilirubin(straight line); N: negative; P: positive.</p

The infant fulminant hepatitis B (IFHB) Risk Score to predict fulminant hepatitis B in infancy.

<p>*The score was 0 for positive maternal HBeAg patients and 1 for negative maternal HBeAg patients.</p>#<p>The score was 0 for onset age ≥7 month-old and 2 for onset age <7 month-old.</p>$<p>The score was 0 for positive HBeAg patients and 1 for negative HBeAg patients.</p><p>The infant fulminant hepatitis B (IFHB) Risk Score to predict fulminant hepatitis B in infancy.</p

Cumulative HBeAg seroconversion rates in survivors of infantile fulminant/non-fulminant hepatitis B (N = 9).

<p>Cumulative HBeAg seroconversion rates in survivors of infantile fulminant/non-fulminant hepatitis B (N = 9).</p

Clinical characteristics and outcome of 21 infants with fulminant hepatitis B.

<p>HBsAg, hepatitis B surface antigen; HBeAg, hepatitis B e antigen, HBV, hepatitis B virus;</p><p>HBIG, hepatitis B immunoglobulin; ALT, alanine aminotransferase; INR, international normalized ratio.</p><p>Clinical characteristics and outcome of 21 infants with fulminant hepatitis B.</p