Cellular compatibility of highly degradable bioactive ceramics for coating of metal implants.

Resorbable ceramics can promote the bony integration of implants. Their rate of degradation should ideally be synchronized with bone regeneration. This study examined the effect of rapidly resorbable calcium phosphate ceramics 602020, GB14, 305020 on adherence, proliferation and morphology of human bone-derived cells (HBDC) in comparison to ß-TCP. The in vitro cytotoxicity was determined by the microculture tetrazolium (MTT) assay. HBDC were grown on the materials for 3, 7, 11, 15 and 19 days and counted. Cell morphology, cell attachment, cell spreading and the cytoskeletal organization of HBDC cultivated on the substrates were investigated using laser scanning microscopy and environmental scanning electron microscopy. All substrates supported sufficient cellular growth for 19 days and showed no cytotoxicity. On each material an identical cell colonisation of well communicating, polygonal, vital cells with strong focal contacts was verified. HBDC showed numerous well defined stress fibres which give proof of well spread and strongly anchored cells. Porous surfaces encouraged the attachment and spreading of HBDC. Further investigations regarding long term biomaterial/cell interactions in vitro and in vivo are required to confirm the utility of the new biomaterials.

Diagnostic management of orthostatic intolerance in the workplace.

OBJECTIVE: Orthostatic intolerance (OI) is a syndrome that is characterised by headache, concentration difficulties, palpitation of the heart, dizziness associated with postural tachycardia and plasma norepinephrine concentrations that are disproportionately high when the sufferer is in the upright posture. In contrast to other forms of orthostatic dysregulation - orthostatic hypotension (OH) and postural orthostatic tachycardia syndrome (POTS) - OI, hitherto, could be diagnosed only by a tilt table examination, with high expenditure. In this paper we examine the reliability and validity of a questionnaire as a screening instrument for OI. METHODS: We studied 138 young men (mean age 21.6 years) who were undergoing military service. After a medical check and filling in the questionnaire, the participants underwent a tilt table test including monitoring of blood pressure, heart rate and plasma catecholamines, in the supine position and during 30 min of standing. The questionnaire consisted of ten items registering presence and frequency of typical OI symptoms. RESULTS: Probands (104) showed normal tilt table test results. OI was diagnosed in 14 probands, OH in 6 and POTS in 14. The OI participants scored significantly higher in the questionnaire than the healthy subjects did: the mean score of the OI group was 22.6, the healthy participants had a mean score of 3.9. Participants with POTS had a mean score of 13.5 and subjects with OH had a mean score of 17.0. Reliability analysis showed a Cronbach's alpha of 0.888. Validity analysis showed that 93.5% of the probands with any kind of orthostatic dysregulation can be detected. CONCLUSIONS: We were able to establish a short questionnaire as a reliable and valid screening instrument for OI. Usage of this questionnaire can simplify enormously the diagnostic management of patients with suspected OI.

Comparison of antimicrobial use and resistance of bacterial isolates in a haematology ward and an intensive care unit.

The objective of the study presented here was to compare antimicrobial use and resistance of bacterial isolates in the haematology ward and the intensive care unit of Bolzano General Hospital. The bacterial organisms isolated most frequently from patients in the two wards (coagulase-negative staphylococci, Enterococcus spp., and Pseudomonas aeruginosa) were investigated for antimicrobial resistance. Isolates obtained from patients in the haematology ward were more often resistant to antimicrobial agents than isolates obtained from patients in the intensive care unit, and the agents against which the highest rates of resistance were found were third- and fourth-generation cephalosporins, carbapenems and monobactams, quinolones, aminoglycosides, and trimethoprim-sulfamethoxazole. These classes of antimicrobial agents were also used more frequently in the haematology ward than in the intensive care unit. Conversely, penicillinic beta-lactam antibiotics, rifamycins, macrolides and lincosamides were used less frequently in the haematology ward than in the intensive care unit, and the rates of resistance against these classes of antimicrobial agents were significantly lower in the haematology ward than in the intensive care unit. The results support the hypothesis that a causal relationship exists between antimicrobial use and the development of resistance and indicate that careful monitoring of antimicrobial use in hospitals is required to identify situations in which prescription patterns are contributing to the development of resistance.

Procalcitonin-reduced sensitivity and specificity in heavily leucopenic and immunosuppressed patients.

Procalcitonin (PCT) has proven to be a very sensitive marker of sepsis for non-leucopenic patients. Little is known about its relevance in immunosuppressed and leucopenic adults. Four hundred and seventy-five PCT determinations were carried out in 73 haematological patients: on 221 occasions the white blood cell (WBC) count was < 1.0 x 10(9)/l and on 239 occasions it was > 1.0 x 10(9)/l leucocytes. Patients were classified as: non-systemic infected controls (n = 280), patients with bacteraemia (n = 32), sepsis (n = 30), severe sepsis (n = 3), septic shock (n = 3) and systemic inflammatory response syndrome (SIRS) (n = 62). When the WBC count was > 1.0 x 10(9)/l, gram-negative bacteria induced higher PCT levels (median 9.4 ng/ml) than gram-positives (median 1.4 ng/ml). In cases with a WBC < 1.0 x 10(9)/l, PCT levels were similar for gram-negative and gram-positive bacteria (1.1 ng/ml versus 0.85 ng/ml). Regardless of the leucocyte count, the median PCT level in bacteraemia cases always remained < 0.5 ng/ml. In heavily leucopenic situations, PCT levels were never > 2 ng/ml even in the sepsis and severe sepsis/septic shock groups, whereas a WBC count > 1.0 x 10(9)/l resulted in median PCT values of 4.1 ng/ml and 45 ng/ml respectively. The positive predictive value for sepsis (cut-off 2 ng/ml) was 93% in cases of WBC count > 1.0 x 10(9)/l, but only 66% in leucopenic conditions. The negative predictive value (cut-off 0.5 ng/ml) was 90% when the WBC count was > 1.0 x 10(9)/l and 63% in leucopenic conditions. Procalcitonin is an excellent sepsis marker with a high positive- and negative-predictive value in patients with WBC count > 1.0 x 10(9)/l, but it does not work satisfactorily below this leucocyte count.

Severe pneumonia in pregnancy three months after resolution of cutaneous zoster.

A 22 weeks pregnant women was affected by a life-threatening pneumonia and a paresis of the proximal muscles with cerebrospinal fluid pleocytosis. Her past medical history had been unremarkable except for recurrent episodes of paraumbilical herpes zoster. The clinical findings suggested a dissemination of varicella-zoster virus without skin lesions. Acyclovir was added to the therapy, and the clinical picture began to improve. Varicella-zoster virus DNA was detected in placental tissue by DNA-hybridisation analysis.

[Cerebral edema: osmotic therapy in clinical practice]. / Edema cerebrale: la terapia osmotica nella pratica clinica.

Having described the therapeutic protocol to be followed in cases of cerebral edema, starting with aspecific measures (hyperventilation in a position of 30 degrees, etc.) for slight cases and progressing to specific therapy (osmotherapy, barbiturates) for more severe cases, the paper focuses on osmotherapy and illustrates the theoretical principles on which it is based and its use in clinical practice.

[The effect of pre-oxygenation on hemodynamics and oxygen consumption]. / Einfluss der Präoxygenierung auf Hämodynamik und Sauerstoffverbrauch.

Pre-oxygenation is routinely used prior to anesthesia and intubation. In awake, premedicated patients scheduled for major aortic surgery we assessed the effects of breathing oxygen for 10 min via a loosely fitting face mask on hemodynamics and oxygen consumption (VO2). RESULTS. O2-breathing increased arterial PO2 to 51 +/- 13 kPa and decreased VO2 from 109 +/- 18 to 92 +/- 24 ml.min-1.m-2 (P less than 0.001 for both variables). This reduction of VO2 resulted from both a fall in cardiac index from 3.22 +/- 0.67 to 3.04 +/- 0.75 1.min-1/m-2 (P less than 0.05) and a decrease in arterio-venous oxygen content difference from 3.45 +/- 0.60 to 3.03 +/- 0.57 ml/dl (P less than 0.001). Systemic peripheral vascular resistance increased slightly from 1453 +/- 359 to 1538 +/- 383 dyne.s.cm-5.m-2 (P less than 0.05). CONCLUSIONS. These results indicate that an increase in F1O2 in patients without severe limitations of oxygen uptake by the lungs or oxygen transport to the tissues does not improve tissue oxygenation. We speculate that increased peripheral shunting acts to protect tissue PO2 during high arterial PO2 levels.

[Catheter induced rupture of a proximal pulmonary artery caused by vigorous coughing in a spontaneously breathing patient]. / Katheterbedingte Ruptur einer proximalen Pulmonalarterie durch heftiges Husten bei spontan atmender Patientin.

A complication is occurred during insertion of a pulmonary artery catheter in a 73-year-old woman with class III NYHA cardiac failure. After easy insertion of the catheter, massive haemoptysis developed as the patient coughed while the balloon of the catheter was inflated. Despite prompt emergency measures, the patient did not survive. Autopsy revealed a 2.7-cm perforation of the proximal pulmonary artery with penetration into the right lower lobe bronchus. This complication and its prevention are discussed.