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This article describes the design and the characterization of the ANTIGONE (ANalog To dIGital cONvErter) ASIC (Application Specific Integrated Circuit) built in AMS 0.35 m technology for low dc-current sensing. This energy-efficient ASIC was specifically designed to interface with multiple Ion-Sensitive Field-Effect Transistors (ISFETs) and detect biomarkers like pH, Na+, K+ and Ca2+ in human sweat. The ISFET-ASIC system can allow real-time noninvasive and continuous health monitoring. The ANTIGONE ASIC architecture is based on the current-to-frequency converter through the charge balancing principle. The same front-end can digitize multiple currents produced by four sweat ISFET sensors in time multiplexing. The front-end demonstrates good linearity over a dynamic range that spans from 1 pA up to 500 nA. The consumed energy per conversion is less than 1 J. The chip is programmable and works in eight different modes of operation. The system uses a standard Serial Peripheral Interface (SPI) to configure, control and read the digitally converted sensor data. The chip is controlled by a portable device over Bluetooth Low Energy (BLE) through a Microcontroller Unit (MCU). The sweat sensing system is part of a bigger wearable platform that exploits the convergence of multiparameter biosensors and environmental sensors for personalized and preventive healthcare.

We describe molecular genetic findings in a patient who initially presented with an intermediate teratoma of the testis and who many years later presented with an oligodendro-astrocytoma. In addition he developed a malignant histiocytoma over the scapula, an adenocarcinoma of the stomach and a late stage adenoma of the sigmoid colon. Due to the development of several neoplasms the possibility of either ataxia telangiectasia or Li-Fraumeni syndrome was considered in differential diagnosis. A molecular genetic investigation revealed that both he and his brother carried a germline p53 tumor suppressor gene mutation at codon 248. From this result we conclude that this family belongs to the Li-Fraumeni syndrome. Once characterized as belonging to the Li-Fraumeni syndrome, the remaining members of the family were typed to determine if they too carried the same mutation. The two children of the index patient were shown not to carry the mutation and are therefore at no increased risk of developing any of the Li-Fraumeni spectrum of malignancies. A molecular genetic investigation into similar families could help to prevent the development of additional malignancies as seen in the index patient, as radiotherapy may interfere with the normal function of the p53 protein and this may in turn help to orchestrate DNA repair after radiation.

A now 42-year-old Thai woman was known to have been anaemic since childhood. When aged 33 years she was diagnosed as having beta zero/HBE thalassaemia. Computed tomography demonstrated a tumour in the posterior mediastinum, histologically found to be an extramedullary haematopoietic focus. Subcutaneous infusion of deferoxamine (2 g five times weekly), initiated because of massive iron overload, reduced the serum ferritin level from 3,460 ng/ml to less than 500 ng/ml. The haemoglobin level in the subsequent years was between 6 and 8 g/dl. Five years later sensory deficits were noted from the 5th thoracic vertebra downwards. Magnetic resonance imaging demonstrated a tumour which compressed the spinal cord: it, too, was an ectopic haematopoietic focus. The neurological symptoms disappeared after radiotherapy with 3,000 cGy, but they recurred 4 years later. Because of the low radiation reserve of the spinal cord, hypertransfusion treatment was initiated, namely 16 RBC concentrates within 4 months and afterwards two transfusions every 3 months. By this means the haemoglobin level was kept at about 9 g/dl. The tumour had regressed 4 months after onset of treatment. For 2 years since the beginning of the hypertransfusion treatment the patient has remained free of neurological symptoms.