Collagen-chondroitin sulfate-based PLLA-SAIB-coated rhBMP-2 delivery system for bone repair

Bone morphogenetic proteins (BMPs) are osteoinductive proteins used intensively in clinical investigations involving various bone-related treatments. Owing to their high potential in new bone formation they require local application at the treatment site. For this purpose various controlled delivery systems with BMPs as the excipients have been prepared in recent years. Focusing on this clinical need a disc-shaped BMP carrier was designed as a local delivery system using soluble collagen and chondroitin sulfate. In situ release studies carried out with a model protein (FITC-labeled Protein A) presented a very high rate of release; with most of the protein content being released within 24 h. This rate could be decreased by providing a poly(L-lactide) (PLLA) and sucrose acetate isobutyrate-based (SAIB-based) coat around the release system, applied after BMP loading. In this way, it was possible to extend the release period from 24 h to about 12 days. In situ release of BMP from the same carriers, as quantitated using an ELISA kit, was even slower, with 50% of the protein being released in 15 days. In order to be able to secure the BMP delivery system at the bone defect site and to provide support a mesh knitted using Vicryl sutures and bonded with poly(L-lactide-co-glycolide) (PLGA) was tested in in vivo. Two time periods, 1 and 3 weeks, were used to evaluate the healing process. Osteoinduction by the BMP carrier system was assessed by histology-based bone scoring and X-ray examinations. PLLA-SAIB-coated collagen discs containing BMP presented good biocompatibility and optimum osteogenic stimulation. Structural changes in histological micrographs at week 1 indicated dose-dependent periosteal ossification. At the end of week 3 histological findings with both BMP (1 and 2 microg) doses were almost the same.     

The Effect of Renal Replacement Therapies on Serum Gastrointestinal System Hormones

Background. The kidney is a major site for the inactivation, degradation, and clearance of a variety of peptide hormones. It has been shown that the uremia increases or decreases gastrointestinal system (GIS) hormones. Moreover, studies investigating the serum GIS hormones levels in chronic renal failure (CRF) were conducted mainly in a particular period of the renal replacement therapy, and the changes caused by continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD) could not be fully demonstrated. In this study, we investigated the effect of CAPD and HD on serum GIS hormones (amylase, lipase, trypsinogen, and gastrin) levels in CRF patients who were diagnosed for the first time. Methods. Serum amylase, lipase, trypsinogen, and gastrin levels were measured in 36 patients who were just diagnosed with CRF, 22 patients with CAPD and 14 patients with HD. GIS hormones of these patients were measured before treatment and three months from the beginning of CAPD and HD treatment. As the control group, 20 normal healthy cases with well-matched age and gender were used. Results. The mean serum amylase, lipase, secretin, and gastrin levels were found meaningfully decreased according to the beginning values at third months of the CAPD and HD treatment. However, they were higher than control group. Conclusion. In patients receiving CAPD or HD as renal replacement therapy, GIS hormone levels were found to be lower, albeit higher than the healthy control group.     

Chlamydia and atherosclerotic coronary arterial disease in Turkey

OBJECTIVE: Chlamydia pneumoniae, which is a Gram(-) intracellular bacteria, besides being a respiratory pathogen, is thought to play an active role in the progress of acute myocardial infarction and chronic coronary artery disease. In this study we aim to determine the frequency of C. pneumoniae in coronary artery lesions of Turkish people. METHODS AND RESULTS: The atherosclerotic material taken from 8 cases by directional atherectomy and from 23 cases by surgical endarterectomy and examined by indirect immunofluorescence (IIFA) test and polymerase chain reaction (PCR). C. pneumoniae positivity was 32.3% (10/31) by IIFA and 29.0% (9/31) by PCR while the evaluation of the methods together yield a positivity of 35.5% (11/31). CONCLUSIONS: A statistically significant difference could not be established between C. pneumoniae positive and negative groups according to age and the classical atherosclerotic risk factors such as diabetes mellitus, smoking, hypercholesterolaemia, hypertension, family history; besides, a statistically significant difference could not be found between the presence of C. pneumoniae and the severity and clinical picture of coronary artery disease.     

Serum acetylcholinesterase and prognosis of acute organophosphate poisoning

OBJECTIVE: The aim of this study is to investigate the prognostic value of serum acetylcholinesterase levels and their relationship with neurological syndromes (Type 1 syndrome, intermediate syndrome, and delayed polyneuropathy) in acute organophosphate poisoning. MATERIALS AND METHODS: Thirty-two consecutive patients with acute organophosphate poisoning admitted to the Ondokuz Mayis University Emergency Department from June 1999 to January 2001 were evaluated. Patients were assessed according to admission time, symptoms, and results of clinical exams and their serum acetylcholinesterase levels were determined on days 1, 2, 3, 7, and the last day. RESULTS: There was no significant difference between the first-day serum acetylcholinesterase of the patients with severe poisoning (n = 22, 68.75%) and of the patients with mild poisoning (n = 10, 31.25%; NS). There was no discernible difference between the serum acetylcholinesterase obtained on days 1 and 3 after poisoning from the patients with intermediate syndrome (n = 5, 15.6%; means: 0.90 +/- 0.65 vs. 0.88 +/- 0.53, 19.35 vs. 18.92%; NS, sensitivity = 80%; specificity = 87.5%). There was a significant difference between the serum acetylcholinesterase obtained on days 1 and 3 from the patients with nonintermediate syndrome (n = 24, 75%; means: 1.05 +/- 0.24 vs. 1.68 +/- 0.29, 22.58 vs. 36.12%; p < 0.001). There was no discernible significant difference in serum acetylcholinesterase between the patients with organophosphorus-induced delayed polyneuropathy (n = 7, 21.8%) and nonorganophosphorus-induced delayed polyneuropathy. In the patients who died (n = 5, 15.6%), serum acetylcholinesterase showed no discernible increase day 1-the last day (means: 0.50 +/- 0.25 vs. 0.46 +/- 0.26, 10.75 vs. 9.89%; NS). There was a significant difference between the serum acetylcholinesterase levels obtained on days 1 and the last day from the patients who survived (n = 27, 84.3%; means: 1.14 +/- 0.25 vs. 2.32 +/- 0.26, 24.51 vs. 49.89%; p < 0.001). CONCLUSION: In the acute phase of organophosphate poisoning, low serum acetylcholinesterase (> 50% of minimum normal value) supports the diagnosis of organophosphate poisoning but it does not show a significant relationship to the severity of poisoning (NS). The serum acetylcholinesterase activity may be a useful parameter in following the acute prognosis of organophosphate poisoning.     

Preemptive diclofenac reduces morphine use after remifentanil-based anaesthesia for tonsillectomy

BACKGROUND: We investigated the effect of preincisional rectal diclofenac on pain scores and postoperative morphine requirements of children undergoing tonsillectomy after remifentanil-propofol anaesthesia in a randomized clinical trial. METHODS: Induction and maintenance of anaesthesia were with remifentanil and propofol. Forty children were randomly assigned into two groups before incision. The diclofenac group (n=20) received diclofenac suppositories (approximately 1 mg x kg(-1)) and the control group (n=20) received no treatment. Following discontinuation of remifentanil, patient-controlled analgesia (PCA) with morphine (a loading dose 50 micro g x kg(-1), a background infusion 4 micro g x kg(-1) x h(-1) and a demand dose 20 micro g x kg(-1) with 5-min intervals) was started. We assessed pain score [verbal analogue scales (VAS), 0-10] and sedation level at 5-min intervals and recorded the total morphine consumption of the first hour in the PACU. Patients were discharged to the ward with a new PCA morphine programme (a demand dose 20 micro g.kg-1 with a lockout time of 30 min, for 4 h), and total morphine consumption was recorded. RESULTS: The mean VAS score of the diclofenac group was significantly lower than the control group on arrival in the PACU (2.85 +/- 0.77, 7.60 +/- 0.83, respectively, P < 0.01) and it remained significantly lower in the PACU stay of the children. The mean total morphine consumption of the diclofenac group was less than the control group in the PACU (130.33 +/- 11.26 and 169.92 +/- 9.22, respectively, P=0.012) and the ward (50.80 +/- 11.38 and 87.77 +/- 10.55, respectively, P=0.021). CONCLUSIONS: Preemptive diclofenac given rectally reduced pain intensity and morphine requirements of children anaesthetized with remifentanil for tonsillectomy.     

Management of acute calculous cholecystitis in high-risk patients: percutaneous cholecystotomy followed by early laparoscopic cholecystectomy

Emergency cholecystectomy for acute cholecystitis is associated with high morbidity and mortality rates in patients with significant comorbidities and high-risk surgery. The aim of this study was to evaluate the effectiveness, possible advantages, and complications of percutaneous cholecystostomy (PC) followed by an early laparoscopic cholecystectomy (LC) in relation to conservative treatment followed by a delayed LC in high-surgical risk patients. Between 2002 and 2004, patients were randomly classified into 2 groups: the first group consisted of patients who had PC followed by an early LC (PCLC group, n = 31) and the second group consisted of patients who had conservative treatment followed by a delayed LC (DLC group, n = 30). The groups were statistically compared regarding their demographic, comorbidity, hospital stay, conversion, and complication rates. PC was technically successful in 31 patients with no attributable mortality or major complications. No difference had been found in regarding demographic, comorbidity, and complication rates. In PCLC group, all the patients experienced symptom relief within 24 hours, and early LC was attempted in 31 patients once their clinical condition was sufficiently stable, this was successfully accomplished in 29 (93.5%). In the DLC group, delayed LC was attempted in 30 patients, and this was successfully accomplished in 26 (86.6%). The hospital stay was shorter and cost was in the PCLC group was lower than in the DLC group. PC allows resolution of sepsis in patients at high surgical risk. Early LC could be safely performed once sepsis and acute infection resolved in these patients.