Deformation-based shape analysis of the hippocampus in the semantic variant of primary progressive aphasia and Alzheimer’s disease

Background Increasing evidence shows that the semantic variant of primary progressive aphasia (svPPA) is characterized by hippocampal atrophy. However, less is known about disease-related morphological hippocampal changes. The goal of the present study is to conduct a detailed characterization of the impact of svPPA on global hippocampus volume and morphology compared with control subjects and patients with Alzheimer’s disease (AD). Methods We measured hippocampal volume and deformation-based shape differences in 22 patients with svPPA compared with 99 patients with AD and 92 controls. Multiple Automatically Generated Templates Brain Segmentation Algorithm (MAGeT-Brain) was used on MRI images obtained at the diagnostic visit. Results Comparable left and right hippocampal atrophy were observed in svPPA and AD. Deformation-based shape analysis showed a common pattern of morphological deformation in svPPA and AD compared with controls. More specifically, both svPPA and AD showed inward deformations in the dorsal surface of the hippocampus, from head to tail on the left side, and more limited to the anterior portion of the body in the right hemisphere. These results also pointed out that both diseases are characterized by a lateral displacement of the central part (body) of the hippocampus. Discussion Our study provides critical new evidence of hippocampal morphological changes in svPPA, similar to those found in AD. These findings highlight the importance of considering morphological hippocampal changes as part of the anatomical profile of patients with svPPA

Balloon pulmonary valvuloplasty in carcinoid syndrome

Half of all patients with carcinoid syndrome develop cardiac involvement. Patients who have cardiac involvement have a significantly worse prognosis than those without, and death can occur directly as a result of cardiac involvement. A case of carcinoid syndrome in a 38 year old woman with lesions in the liver, who presented with right sided valvar abnormalities, a dilated right ventricle, and right ventricular pressure overload, is presented. In order to palliate the patient's symptoms and to decrease right sided pressures before major abdominal surgery, balloon pulmonary valvuloplasty was performed at the time of cardiac catheterisation. This resulted in a reduction in the pulmonary gradient and right ventricular pressure. Following the procedure, the patient's symptoms were completely relieved. She went on to laparotomy where the lesions in the liver were excised without complication.


Keywords: carcinoid syndrome; balloon pulmonary valvuloplast

Computer-assisted method for compiling a blood group register

The compilation of the records of a serology department using a computer to produce alphabetically ordered files is described. This has proved to be an efficient and economical technique which may well be applied to other similar problems in a large clinical laboratory

Proline residues in transmembrane segment IV are critical for activity, expression and targeting of the Na+/H+ exchanger isoform 1.

NHE1 (Na+/H+ exchanger isoform 1) is a ubiquitously expressed integral membrane protein that regulates intracellular pH in mammalian cells. Proline residues within transmembrane segments have unusual properties, acting as helix breakers and increasing flexibility of membrane segments, since they lack an amide hydrogen. We examined the importance of three conserved proline residues in TM IV (transmembrane segment IV) of NHE1. Pro167 and Pro168 were mutated to Gly, Ala or Cys, and Pro178 was mutated to Ala. Pro168 and Pro178 mutant proteins were expressed at levels similar to wild-type NHE1 and were targeted to the plasma membrane. However, the mutants P167G (Pro167-->Gly), P167A and P167C were expressed at lower levels compared with wild-type NHE1, and a significant portion of P167G and P167C were retained intracellularly, possibly indicating induced changes in the structure of TM IV. P167G, P167C, P168A and P168C mutations abolished NHE activity, and P167A and P168G mutations caused markedly decreased activity. In contrast, the activity of the P178A mutant was not significantly different from that of wild-type NHE1. The results indicate that both Pro167 and Pro168 in TM IV of NHE1 are required for normal NHE activity. In addition, mutation of Pro167 affects the expression and membrane targeting of the exchanger. Thus both Pro167 and Pro168 are strictly required for NHE function and may play critical roles in the structure of TM IV of the NHE