Changes in the brain during long-term follow-up after liver transplantation

Purpose:

To examine changes in the brain before liver transplantation caused by the accumulation of paramagnetic ion deposits and to investigate recovery after liver transplantation over a long‐term horizon.

Materials and Methods:

Fifteen patients indicated for liver transplantation, 26 patients up to 2 years after, and 40 patients 8–15 years after liver transplantation were subjected to MR relaxometry. T₁ and T₂ relaxation times in the basal ganglia, thalamus, and white matter were evaluated.

Results:

Relaxometry revealed a shortening of the relaxation times due to the deposition of paramagnetic ions in the basal ganglia before liver transplantation (P < 0.05), complete normalization of the relaxation times shortly after transplantation in the globus pallidus and caudate nucleus, and partial recovery of T₂ in the putamen. Relaxation times remained stable even 15 years posttransplantation. Increased relaxation times posttransplantation were found in the white matter and thalamus.

Conclusion:

The shortening of the relaxation times observed in the basal ganglia before liver transplantation was caused by paramagnetic ion deposition. The recovery observable within 2 years after transplantation was permanent, and no recurrence of paramagnetic ion deposition was observed even 15 years posttransplantation. Changes in the white matter and thalamus after transplantation were attributed to damage caused by permanent exposure to immunosuppressants. J. Magn. Reson. Imaging 2012;35:1332–1337. © 2012 Wiley Periodicals, Inc.     

Prevalence of HIV Infection and Risk Behaviors Among Younger and Older Injecting Drug Users in the United States, 2009

This study compared HIV sero-prevalence and risk behaviors between younger and older injecting drug users (IDUs). IDUs aged ≥18 years were interviewed for the 2009 National HIV Behavioral Surveillance System. Using GEE regression, we assessed characteristics of younger (18–29 years) and older (≥30 years) IDUs, and factors associated with past 12-month receptive syringe sharing and unprotected sex (vaginal/anal). Of 10,090 participants, 10 % were younger. HIV sero-prevalence was lower among younger than older IDUs (4 vs. 10 %, p = 0.001). Younger IDUs were more likely (p ≤ 0.002) to be non-black race/ethnicity, report higher household income, homelessness, being arrested and to engage in receptive syringe sharing and unprotected sex. In multivariable models, age remained associated (p < 0.001) with receptive syringe sharing (aPR = 1.14, 95 % CI1.07–1.22) and unprotected sex (aPR = 1.10, 95 % CI1.06–1.14). Although younger IDUs had lower HIV prevalence, their behaviors place them at increased risk of HIV infection and could lead to a rapid spread in this susceptible population.     

Transformation of lymphocytes in patients with certain bacterial infections

The state of cell-mediated immunity was measured by the morphological method of lymphocyte transformation with and without PHA, in a group of 56 patients with bacterial infections and in a group of healthy controls. The patients were divided into three subgroups according to the aetiology: 1. Patients with Gram-positive infections, 2. Patients with Gramn-egative infections, and 3. mixed infections. The transformation values without PHA were significantly (t-test) higher in the Gram-positive subgroups than in the control group. Transformation in cultures stimulated by PHA was much higher in the subgroup of patients with Gram-positive aetiology; the difference between the values in the Gram-negative and in the Gram-positive subgroups was also significant. A decrease of transformation value below 50% was observed in 6 out of 18 patients with Gram-negative aetiology, whereas in the Gram-positive group it was noted in only 2 out of 21 patients.