Structure of human transferrin receptor oligosaccharides: conservation of site-specific processing.

The human transferrin receptor (TfR) has three N-linked oligosaccharides. A combination of site-directed mutagenesis and carbohydrate and protein chemistry was used to characterize the structures of the N-linked oligosaccharides and to map their locations. We find that the type of oligosaccharide at each position was unique for that particular site.

The Requirements of an Electronic Medical Record to Suit all Clinical Disciplines.

The design of the electronic medical record is becoming increasingly sophisticated as techniques develop to improve the understanding of user requirements. Such techniques must develop as it becomes increasingly important to improve the use and uptake of such records. An outstanding question is whether the same electronic medical record can fulfil the requirements of users in different clinical disciplines.

A new approach to Kanerva's sparse distributed memory.

The sparse distributed memory (SDM) was originally developed to tackle the problem of storing large binary data patterns. The model succeeded well in storing random input data. However, its efficiency, particularly in handling nonrandom data, was poor.

Development of a smart holmium:YAG laser lithotriptor.

Background And Objective: The purpose of this study was to develop a feedback control system for the pulsed holmium:YAG medical laser that enhances tissue selectivity and safety by discriminating between soft and hard biological tissue such as urinary and biliary calculi and bone.

Study Design/materials And Methods: The ability to discriminate is achieved by monitoring prompt laser-induced visible/NIR photoemissions via retrograde transmission over the laser delivery fiber in conjunction with a developed detection algorithm.

Results: Experimental data are presented for a system that employs this discrimination scheme with an electro-optic shutter for rapid intrapulse feedback control of holmium laser-based lithotripsy procedures.

Renal Na/Pi-cotransporters.

Two non-homologous proximal tubular apical Na/Pi-cotransport systems (type I and type II) have been identified thus far by expression cloning. Subsequent studies provided evidence that the type II Na/Pi-cotransporter represents a target for the physiological and pathophysiological regulation of proximal reabsorption of phosphate. The exact role of the type I Na/Pi-cotransporter in proximal Pi-reabsorption and eventually also in the renal handling of other substrates, such as organic anions, is currently less clear and needs further investigation.

Taking the problem oriented medical record forward.

The problem oriented medical record (POMR) has proved to be very successful in providing a structure that helps doctors record their notes about patients, and view those notes subsequently in a manner that quickly gives them a good understanding of that patients history. This approach has been validated by the American Institute of Medicine. With the increased use of computer systems that implement the POMR by doctors, the limitations of this structure have become apparent, and there is clearly scope for developing the model further to improve the quality of the data recorded, and adding meaning to it.

Medical records: past, present, and future.

This paper considers the lessons learnt during the development of the electronic medical record for patient care. It is not a definitive history of medical records but an assessment of what has been learnt, what has to be learnt and how we can move forward. It considers the needs for structured intelligent records that help in individual patient care, the need to provide functionality that fits with the requirements of the clinician-patient interaction and the need to take into account the human factors that affect clinician's uptake of such systems.

Stimulation of ecdysteroidogenesis by small prothoracicotropic hormone: role of calcium.

Insect prothoracic glands are regulated by neuropeptide prothoracicotropic hormones (PTTH). In Manduca sexta PTTH exists as two size variants, big PTTH (approximately 25.5 kDa) and small PTTH (approximately 7 kDa).

Protein kinase C consensus sites and the regulation of renal Na/Pi-cotransport (NaPi-2) expressed in XENOPUS laevis oocytes.

Renal brush border membrane sodium/phosphate (Na/Pi)-cotransport activity is inhibited by hormonal mechanisms involving activation of protein kinases A and C. The recently cloned rat renal Na/Pi-cotransporter (NaPi-2) contains several protein kinase C but no protein kinase A consensus sites [17, 20]. In the present study we have expressed wild type and polymutant (protein kinase C consensus sites removed) NaPi-2-transporters in Xenopus laevis oocytes.

Expression of parathyroid hormone receptors in MDCK and LLC-PK1 cells.

Parathyroid hormone (PTH) inhibits renal proximal tubular phosphate (Pi) and bicarbonate reabsorption by regulating the activity of apical Na/Pi cotransport and Na/H exchange. Two renal epithelial cell lines ["proximal tubular", LLC-PK1; "distal tubular", Madin-Darby canine kidney, (MDCK) cells] were stably transfected with complementary deoxyribonucleic acids (cDNAs) encoding a cloned PTH receptor in order to examine the polarity of transfected receptor function and whether or not intrinsic Pi transport is regulated by the transfected PTH receptor. The receptors are functionally coupled to the stimulation of adenosine 3':5' cyclic monophosphate (cAMP) production at both cell surfaces in LLC-PK1 cells, whereas this response is primarily limited to the basolateral surface in MDCK cells.

Perforation of the small bowel: a case report.

Nontraumatic perforation of the small bowel is rare. A 71-year-old man presented with a perforated jejunum 8 weeks after receiving streptokinase therapy for acute myocardial infarction. This was complicated by a bleeding duodenal ulcer, renal failure, ischemia of one toe and confusion.

The critical glycosylation site of human transferrin receptor contains a high-mannose oligosaccharide.

The human transferrin receptor (TfR) contains three N-linked oligosaccharides and glycosylation is required for the proper folding and function of the molecule. Earlier studies demonstrated that the oligosaccharide at Asn-727 is vital for the production of fully active TfR. The oligosaccharide(s) present at this site have been analysed using a combination of site-directed mutagenesis and chemical analysis.

Role of N-linked glycosylation in rat renal Na/Pi-cotransport.

Our laboratory recently identified a sodium-dependent transport system for phosphate from rat kidney cortex (NaPi-2; Magagnin, S., Werner, A., Markovich, D.

Electrophysiological analysis of Na+/Pi cotransport mediated by a transporter cloned from rat kidney and expressed in Xenopus oocytes.

Phosphate (Pi) reabsorption in renal proximal tubules involves Na+/Pi cotransport across the brush border membrane; its transport rate is influenced by the Na(+)-coupled transport of other solutes as well as by pH. In the present study, we have expressed a cloned rat renal brush border membrane Na+/Pi cotransporter (NaPi-2) in Xenopus laevis oocytes and have analyzed its electrophysiologic properties in voltage- and current-clamp studies. Addition of Pi to Na(+)-containing superfusates resulted in a depolarization of the membrane potential and, in voltage-clamped oocytes, in an inward current (IP).

Respiratory disease in cotton textile workers: epidemiologic assessment of small airway function.

We performed a cross-sectional study of 705 textile workers in two cotton mills and one silk mill in Shanghai, People's Republic of China, to assess small airway function among cotton textile workers and to compare the FEV1 to the FEF25-75 in detecting airflow obstruction in these workers. All workers had at least 2 years of work experience. Environmental sampling was performed with vertical elutriators and revealed that in the cotton mills mean elutriated dust levels were 1.

A chicken transferrin binding protein is heat shock protein 108.

A previously described transferrin binding protein from chicken oviduct has been identified as a heat shock protein, HSP108, by microsequencing of RP-HPLC purified tryptic peptides. The protein purified from oviduct by SDS-PAGE or from liver by ovotransferrin-affinity chromatography reacts with a monoclonal antibody raised against HSP108. The cDNA sequence predicts of KDEL peptide at the carboxyl terminus, but the protein does not react with anti-KDEL monoclonal antibodies, suggesting that HSP108 is processed in a way that eliminates the KDEL epitope.