Culture and differentiation of chondrocytes entrapped in alginate gels

Summary We studied the response to culture conditions and the differentiative ability in suspension culture in alginate gels of resting chondrocytes from the preosseous cartilage of adult pig scapula. It was found that the maximum rate of chondrocyte duplication is reached at the fourth day in culture whereas the rate of proteoglycan synthesis and alkaline phosphatase expression do not gain a maximum value before the seventh day. During the culture time, the chondrocytes undergo differentiation as it is demonstrated by the alkaline phosphatase specific activity increase and by morphological criteria (hypertrophy, increase of the number of mitochondria per cell, increased endoplasmic reticulum, matrix vesicle production). The alginate gels can be easily dissolved to obtain cell populations in which the variation of cytosolic calcium concentration following a proliferative stimulus can be conveniently observed using the conventional procedure of Fura 2.     

Evaluation of a new automated system for the determination of ck-mb isoforms

We evaluated a new analyzer (Cardio REP) specifically designed for cardiac CK-MB isoenzyme and isoforms activity, with a performance time of 24 minutes. Ten AMI patients, with times elapsed between the onset of chest pain and admission to hospital ranging from 30 minutes to 4 hours, were monitored every 3–4 hours until the 16th hour of hospitalization. In each serum sample, in addition to total CK-MB and CK-MB isoforms measured by the Cardio REP analyzer, we also assayed total CK activity, CK-MB activity by immunoinhibition method, CK-MB mass concentration, CK-MB isoforms by REP method, troponin T, and myoglobin. The precision study demonstrated acceptable within assay and between assay CVs% for total CK-MB (8.1 and 10.4), MB₁ (9.1 and 14.2), and MB₂ (9.1 and 8.2) isoforms. The method was found to be linear up to 371 U/L for MB₂ isoform fraction and up to 516 U/L for total CK-MB. Results for CK-MB obtained with the Cardio REP correlated well with those for CK-MB activity obtained with the immunoinhibition method (r = 0.869) and those of CK-MB mass concentration (r = 0.923). The sensitivity of the Cardio REP CK isoforms method was found to be greater than that of the REP CK isoforms method. Time to first increased value of MB₂/MB₁ ratio and MB₂ isoform was earlier in comparison to that for CK-MB mass concentrations and similar to that for myoglobin, a marker that, however, lacks specificity. The diagnostic efficiency of CK-MB isoforms and the availability of a real-time, fully automated method for their measurement suggest the utilization of this biochemical marker in emergency for the early diagnosis of AMI.     

Clear hydro-gel, compared to ointment, provides improved eye comfort after brief surgery

PURPOSE: Anesthesia impairs lid closure and decreases tear secretion and stability. Protection may, in principle, be conveyed by manual eye closure, taping the eyelids closed, and by instillation of protective substances into the conjunctival sac. Both hydro-gels and ointments are used in clinical practice. It was the objective of the present study to compare a transparent clear ocular hydro-gel (Vidisic) and a commonly used dexpanthenol and vitamin A (Oleovit) based ointment as examples of these classes of ocular lubricants in their capability to provide perioperative eye comfort. Furthermore, their bacteriostatic properties were assessed in vitro. METHODS: Ninety-two consecutive patients undergoing total iv general anesthesia were randomly allocated to receive either ocular dexpanthenol ointment or a clear hydro-gel after induction of anesthesia. Subjects were assessed one hour following termination of anesthesia. RESULTS: Main findings were an increased incidence of foreign body sensation, adherent eyelashes and disturbance elicited by blurred vision in the ointment group as compared to clear hydro-gel (P < 0.001). Bacterial growth was significantly attenuated by the ocular hydro-gel as compared to ointment. DISCUSSION: Clear ocular hydro-gel offers improved patient comfort and decreased ocular inflammation as compared to conventional eye ointments. In addition, it decreases bacterial growth. Therefore, the use of clear ocular hydro-gel for perioperative ocular comfort is suggested.     

The expression of wild-type human amyloid precursor protein affects the dendritic phenotype of neocortical pyramidal neurons in transgenic mice

The current study addresses the morphoregulatory effects of human amyloid precursor protein expression on neocortical pyramidal cells in vivo. For this purpose, a transgenic mouse line was used that expresses wild-type human amyloid precursor protein (APP) at levels similar to endogenous mouse APP. This strain does not develop Alzheimer's disease-related pathology which allowed to study effects of APP or APP cleavage products but excluded the influence of amyloid deposits. Commissural projecting pyramidal neurons of layers II/III within the primary somatosensory cortex were retrogradely labelled by injection of biotinylated dextran amine into the corpus callosum. In transgenic mice, computer-aided morphometric analysis revealed an increase in the surface area of proximal and intermediate basal dendritic segments resulting from an enlarged diameter. On the other hand, the length of the same segments was reduced. Both basal and apical dendrites were characterized by a higher dendritic density within the proximal and intermediate fields. Although the total spatial extension of basal and apical dendrites remained unchanged, a moderate withdrawal of arbors is suggested. The results implicate a physiological function for APP in regulatory mechanisms of neuronal morphogenesis.     

Work and diet-related risk factors of cardiovascular diseases: comparison of two occupational groups

Background  

Although work related risk factors associated with Cardiovascular Diseases (CD) have been well researched, there is no detailed knowledge regarding disparate occupational groups each with a different risk exposition. Therefore, two occupational groups (chefs and office workers) were compared with a focus on nutritional and psychosocial factors.     

Drug prescribing in hospital as experienced by general practitioners: East versus West Germany

BACKGROUND AND OBJECTIVES: Drugs prescribed by the general practitioner (GP) are oftenchanged during hospitalization. This study set out to test thehypothesis that the extent of drug change and the informationprovided by the hospital determines the GPs' assessment of hospitalco-operation. The perception of drug change and hospital co-operationmay also be influenced by the degree of institutional separationof primary and secondary care. Therefore we compared GPs' respectiveattitudes in ‘East’ and ‘West’ Germany. METHOD: In 1993, a representative sample of ‘eastern’ and‘western’ German doctors received a structured questionnaire;554 doctors (63%) participated. RESULTS: Fifty-seven per cent of the western and 39% of the eastern GPsbelieved that their medication was changed in hospital in morethan 60% of their patients. Only a minority of eastern (10%)and western (15%) doctors described the information providedby the hospitals as more or less satisfactory. More westernthan eastern doctors (56% versus 32%) expressed dissatisfactionwith hospital co-operation. Respondents in eastern Germany whofelt sufficiently informed about hospital drug change were morelikely to express satisfaction with the hospital doctors' co-operation.In the former area of West Germany the judgement of co-operationwas significantly better if the extent of drug change and thefrequency of generic drug replacement by original brand-namedrugs were lower. CONCLUSIONS: The study showed that hospital-initiated drug change is a matterof concern, especially for GPs who are working in an area witha tradition of strictly separated primary and secondary care. Keywords. Drug prescribing, family practice, interprofessional relations, health system.     

Synthese von neuen monomeren schwefelhaltigen acryl- und methacrylsäureamid-derivaten aus 3-thiazolinen

Acrylamides containing heteroatoms N, S or O are effective compounds to influence the properties of polymers. On the one hand they determine the chemical and physical behaviour of the synthetic materials, on the other hand they offer new possible applications for such compounds. In this paper a synthetic method affording a new class of monomers prepared from simple educts is described. Thus, 3-thiazolines 3 are allowed to react with alkenoyl chlorides (e. g. acryloyl chloride) to give 3-alkenoyl-4-chlorothiazolidines. Upon hydrolysis the 3-alkenoyl-4-hydroxythiazolidines 6a–d , 7a , b , 8a–d and 9a , b are obtained. Starting from 3-alkenoyl-4-chlorothiazolidines, several 3-alkenoyl-4-methoxythiazolidines 6e , f , 7c and 9c have been synthesized, too.