A. Cuschieri

Laparoscopic Cardiomyotomy for Achalasia

A technique of laparoscopic cardiomyotomy is described. The procedure has been performed in a patient with manometrically confirmed classical achalasia with complete relief of episodic total dysphagia and no untoward symptoms including reflux. The procedure was followed by minimal postoperative discomfort and the patient was discharged on the third postoperative day. Laparoscopic cardiomyotomy has the advantage of diminished surgical trauma with accelerated recovery, constitutes definitive therapy comparable to standard myotomy, and by being less disruptive of the lower oesophageal fixation it is prone to precipitate gastro-oesophageal reflux.

Outcome after cholecystectomy for symptomatic gall stone disease and effect of surgical access: laparoscopic v open approach.

The pre and postoperative symptoms and outcome after surgery in patients with symptomatic gall stone disease were evaluated by a detailed self administered postal questionnaire. The survey was conducted in two groups: 80 patients treated by laparoscopic cholecystectomy and an age matched cohort of patients who had conventional open cholecystectomy. The overall response rate on which the data were calculated was 76%. Symptomatic benefit ratios accruing from the surgical removal of the gall bladder were calculated. The symptoms that were relieved by cholecystectomy were nausea (0.98), vomiting (0.91), colicky abdominal pain (0.81), and backpain (0.76). Flatulence, fat intolerance, and nagging abdominal pain were unaffected as shown by a benefit ratio of 0.5 or less. Relief of heartburn (39/49) outweighed the de novo development of this symptom after cholecystectomy (7/49), resulting in a benefit ratio of 0.65. Postcholecystectomy diarrhoea occurred in 21/118 patients (18%): 10 after open cholecystectomy and 11 after laparoscopic cholecystectomy. The type of surgical access did not influence the symptomatic outcome but had a significant bearing on the time to return to work or full activity after surgery (laparoscopic cholecystectomy two weeks, open cholecystectomy eight weeks, p = 0.00001). In the elderly age group (> 60 years), significantly more patients (29/30) regained full activity after laparoscopic cholecystectomy when compared with the open cholecystectomy group (16/22), p = 0.001. The patient appreciation of a satisfactory cosmetic result was 72% in the open group compared with 100% of patients who were treated by laparoscopic cholecystectomy (p = 0.0017). Despite the persistence or de novo occurrence of symptoms, 111/117 patients (95%) considered that they had obtained overall symptomatic improvement by their surgical treatment and 110/118 (93%) were pleased with the end result regardless of the access used.

Diagnostic yield and management benefit of laparoscopy: a prospective audit.

A prospective audit of the diagnostic yield and management benefit of laparoscopy was undertaken in 220 consecutive patients. The procedure was performed electively in 180 patients and as an emergency in 40. The indications for laparoscopy in the elective group were suspected hepatic disease, staging of intra-abdominal malignancy, diagnostic problems, and chronic abdominal pain. Emergency laparoscopy was performed in patients admitted with acute abdominal pain. Diagnostic benefit varied with the indication for the procedure: liver disease 71%, tumour staging 87%, uncertain diagnosis 74%, acute abdominal pain 100%, and chronic abdominal pain 41%. Clinical management was significantly influenced by laparoscopy in 15 of 21 (71%) patients with liver disease, 10 of 30 (33%) with intra-abdominal malignancy, 5 of 19 (26%) with uncertain diagnosis, 32 of 40 (80%) with acute abdominal pain, and 15 of 110 (23%) patients with chronic abdominal pain. A wrong assessment of the nature or stage of the disease was made by laparoscopy in 3 of 220 (1.0%). There was no morbidity or mortality attributed to laparoscopy in the study.

Magnetic nanoparticles as intraocular drug delivery system to target Retinal Pigmented Epithelium (RPE)

One of the most challenging efforts in drug delivery is the targeting of the eye. The eye structure and barriers render this organ poorly permeable to drugs. Quite recently the entrance of nanoscience in ocular drug delivery has improved the penetration and half-life of drugs, especially in the anterior eye chamber, while targeting the posterior chamber is still an open issue. The retina and the retinal pigment epithelium/choroid tissues, located in the posterior eye chamber, are responsible for the majority of blindness both in childhood and adulthood. In the present study, we used magnetic nanoparticles (MNPs) as a nanotool for ocular drug delivery that is capable of specific localization in the retinal pigmented epithelium (RPE) layer. We demonstrate that, following intraocular injection in Xenopus embryos, MNPs localize specifically in RPE where they are retained for several days. The specificity of the localization did not depend on particle size and surface properties of the MNPs used in this work. Moreover, through similar experiments in zebrafish, we demonstrated that the targeting of RPE by the nanoparticles is not specific for the Xenopus species.

Generation of Magnetized Olfactory Ensheathing Cells for Regenerative Studies in the Central and Peripheral Nervous Tissue

As olfactory receptor axons grow from the peripheral to the central nervous system (CNS) aided by olfactory ensheathing cells (OECs), the transplantation of OECs has been suggested as a plausible therapy for spinal cord lesions. The problem with this hypothesis is that OECs do not represent a single homogeneous entity, but, instead, a functionally heterogeneous population that exhibits a variety of responses, including adhesion and repulsion during cell-matrix interactions. Some studies report that the migratory properties of OECs are compromised by inhibitory molecules and potentiated by chemical gradients. In this paper, we report a system based on modified OECs carrying magnetic nanoparticles as a proof of concept experiment enabling specific studies aimed at exploring the potential of OECs in the treatment of spinal cord injuries. Our studies have confirmed that magnetized OECs (i) survive well without exhibiting stress-associated cellular responses; (ii) in vitro, their migration can be modulated by magnetic fields; and (iii) their transplantation in organotypic slices of spinal cord and peripheral nerve showed positive integration in the model. Altogether, these findings indicate the therapeutic potential of magnetized OECs for CNS injuries.

Microencapsulation of human cells : its effects on growth of normal and tumour cells in vitro

The growth kinetics of established human colorectal tumour cell lines (HT29, HT115 and COLO 320DM) and human diploid fibroblasts (Flow 2002) were studied in conventional culture and in microcapsules formed from alginate-poly(L-lysine)-alginate membranes. The tumour lines grew rapidly in microcapsules but, in the case of the substrate-adherent lines HT29 and HT115, only after a prolonged lag phase. This phase was reduced by serial passage in microcapsules. The anchorage-independent line COLO 320DM showed no lengthening in lag phase. Microencapsulated fibroblasts underwent negligible growth but remained viable. Some evidence for functional differentiation (microvilli, cell-cell junctions) of the tumour line HT115 within the microcapsules was observed. We conclude that the use of microcapsules provides an alternative system with some advantages for the study of human cancer and its metastases in vitro.