Laparoscopic versus open repair for strangulated groin hernias: 188 cases over 4 years.

INTRODUCTION: Currently transabdominal pre-peritoneal and totally extraperitoneal repairs are the two standard laparoscopic approaches for groin hernia repair. However, they are still largely reserved for uncomplicated elective cases. To determine whether laparoscopic groin hernia repair can achieve similar results for acute strangulated hernias as laparoscopic cholecystectomy for acute cholecystitis, we analyzed and compared the results of emergency laparoscopic surgery and open repair for strangulated groin hernias performed by our team over the past 4 years. METHODS: This is a retrospective analysis of prospectively collected data. We analyzed the results of patients admitted between January 2007 and January 2011 who were diagnosed with acute strangulated groin hernia and underwent emergency open or laparoscopic hernia repair during the same admission. Patients' demographic details, mode of presentation, type of hernia, intraoperative findings, operative time, postoperative course and complications were compared. RESULTS: In total, 188 patients fulfilled the criteria for emergency surgical repair of strangulated groin hernias; 57 received laparoscopic and 131 received open repairs. The mean operative time was 79.82 ± 29.571 min and 80.75 ± 35.161 min, respectively. More laparotomies were performed in the open group (19 vs 0). The wound infection rate was significantly higher in the open group (12 vs 0). The mean hospital stay was shorter in the laparoscopic group (4.39 days vs 7.34 days). There was no mesh infection in either group. Recurrence occurred one case in the laparoscopic group and in three cases in the open group. CONCLUSIONS: Emergency laparoscopic repair for strangulated groin hernias is feasible and appears to have a lower morbidity relative to open repair. Further study should be performed to evaluate its full potential.

Single-incision transabdominal preperitoneal and totally extraperitoneal repair for inguinal hernia: early experience from a single center in Asia.

INTRODUCTION: Laparoscopic inguinal hernia repair is currently one of the most commonly performed minimally invasive surgical procedures. In recent years, single-incision operations have been developed to further reduce the invasiveness of the surgery. Herein, we report our early experience with single-incision laparoscopic inguinal hernia repair in Asia, with both the transabdominal preperitoneal (TAPP) and totally extraperitoneal (TEP) approaches. METHODS: This is a retrospective review of prospectively collected data on a cohort of consecutive patients with inguinal hernia who underwent single-incision laparoscopic inguinal hernia repair in a minimal access surgical center in Hong Kong between January 2010 and January 2011. RESULTS: Our cohort consists of 15 patients who underwent single-incision laparoscopic inguinal hernia; 13 were unilateral and two were bilateral hernias. The mean age was 59.8 years old (range, 28-74 years). The overall mean operative time was 59.53 min (range, 25-120 min). For unilateral hernia repair, the mean operative time was 56 min (range, 25-75 min) and 48.5 min (range, 41-55 min) for TAPP and TEP, respectively. In all cases single-incision laparoscopic hernia repair was successfully performed, no additional trocars were required, and there were no conversions to conventional laparoscopic or open inguinal hernia repair. All patients were discharged on the same day as the procedure. CONCLUSION: Single-incision laparoscopic inguinal hernia is feasible in both TEP and TAPP approaches. The procedure should be performed by laparoscopic surgeons with a high level of experience in single-incision surgery. Further randomized trials should be performed to evaluate the full potential and clinical application of single-incision TAPP and TEP.

Effects of photochemical crosslinking on the microstructure of collagen and a feasibility study on controlled protein release.

Photochemical crosslinking is an emerging technique able to modify the physicochemical properties of collagen. However, whether this technique can be used to modify collagen-based structures for drug delivery has not been studied. This study demonstrated that the microporous structure of photochemically crosslinked collagen was affected by rose Bengal and laser energy level. Using the optimized process parameters, the authors fabricated photochemically crosslinked collagen structures encapsulated with sample proteins and demonstrated that photochemical crosslinking reduced the initial burst effect and protein release without compromising the protein bioactivity. The fiber meshwork in collagen structures was also characterized, and it was found that photochemical crosslinking did not significantly alter the mesh size. This study reports the effects of photochemical crosslinking on the microstructure of collagen structures and suggests the feasibility of using photochemically crosslinked collagen structures for controlled protein release.

Fabrication of nano-fibrous collagen microspheres for protein delivery and effects of photochemical crosslinking on release kinetics.

Protein compatibility is important for protein drug delivery using microsphere-based devices. Collagen has excellent protein compatibility but has poor mechanical stability for microsphere fabrication and open meshwork for controlled release. In this study, a protein-compatible fabrication method for injectable collagen microspheres has been developed. The surface morphology, interior microstructure and protein release characteristics of collagen microspheres were investigated. Moreover, effects of photochemical crosslinking on these characteristics were also studied. Finally, the mechanisms governing the protein release and the retention of protein bioactivity were studied. Stable and injectable collagen microspheres consisting of nano-fibrous meshwork were successfully fabricated under ambient conditions in an organic solvent and crosslinking reagent-free manner. These microspheres have open meshwork and showed large initial burst and rapid release of proteins. Photochemical crosslinking significantly reduced the initial burst effect and controlled the protein release in a photosensitizer dose-dependent manner without significantly altering the mesh size. We further demonstrated that there was significantly higher protein retention within the photochemically crosslinked collagen microspheres as compared with the uncrosslinked, suggesting a secondary retention mechanism. Lastly, both surfactant treatment and photochemical crosslinking did not compromise the bioactivity of the encapsulated proteins. In summary, this study reports a novel collagen microsphere-based protein delivery system and demonstrates the possibility to use photochemical crosslinking as the secondary retention mechanism for proteins.

Stapled technique for acute thrombosed hemorrhoids: a randomized, controlled trial with long-term results.

PURPOSE: This study was designed to compare stapled vs. conventional hemorrhoidectomy for patients with acute thrombosed hemorrhoids. METHODS: Forty-one patients with acute thrombosed hemorrhoids were randomized into: 1) stapled hemorrhoidectomy (PPH group; n = 21), and 2) open hemorrhoidectomy (open group; n = 20). Emergency surgery was performed with perioperative data and complications were recorded. Patients were followed up by independent assessors to evaluate pain, recurrence, continence function, and satisfaction at regular intervals. RESULTS: The median follow-up for the PPH group and open group were 59 and 56 weeks, respectively. There was no significant difference in terms of the hospital stay, complication rate, and continence function; however, the mean pain intensity in the first postoperative week was significantly less in the PPH group (4.1 vs. 5.7, P = 0.02). Patients in the PPH group recovered significantly faster in terms of the time to become analgesic-free (4 vs. 8.5 days, P < 0.01), time to become pain-free (9 vs. 20.5 days, P = 0.01), resumption of work (7 vs. 12.5 days, P = 0.01), and time for complete wound healing (2 vs. 4 weeks, P < 0.01). On long-term follow-up, significantly fewer patients in the PPH group complained of recurrent symptoms (0 vs. 5, P = 0.02). The overall symptom improvement and patients' satisfaction were significantly better in the PPH group (90 vs. 80 percent, P = 0.03 and +3 vs. +2, P < 0.01 respectively). CONCLUSIONS: Stapled hemorrhoidectomy is safe and effective for acute thrombosed hemorrhoids. Similar to elective stapled procedure, emergency stapled excision has greater short-term benefits compared with conventional excision: diminished pain, faster recovery, and earlier return to work. Long-term results and satisfaction were excellent.

Ablation of paternal accessory sex glands imparts physical and behavioural abnormalities to the progeny: an in vivo study in the golden hamster.

The functional significance of male accessory sex glands (ASG) remains unclear. This study explored their importance in reproduction. In previous investigations, embryos sired by males with ASG either totally or partially removed had a shift in the cell cycle and delayed cleavage during preimplantation development, higher incidence of apoptosis, early oviductal-uterine transit, higher proportion of embryo degeneration, lower implantation rate, and ultimately reduced fertility and fecundity. Some pups were born alive; but would they be normal? We hypothesized that the first generation offspring (F1) could also bear undesirable traits. To test our hypothesis, we raised and studied these F1 pups from birth to 8 weeks. We monitored physical growth and assessed behaviour such as nest patch odor preference, acoustic startle response (ASR) and exploratory activity. We detected deviations from the norm in physical growth, a premature cessation of nest patch odor preferences, accelerated acoustic startle habituation and more frequent rearing when exposed to a novel environment. In terms of structure, we found one incidence of diphallus with duplicated urethra. We concluded that sperm lacking contact with ASG secretions gave rise to progeny with abnormal traits.

Photochemical cross-linking for collagen-based scaffolds: a study on optical properties, mechanical properties, stability, and hematocompatibility.

Collagen presents an attractive biomaterial for tissue engineering because of its excellent biocompatibility and negligible immunogenicity. However, some intrinsic features related to the mechanical stability and thrombogenicity limit its applications in orthopedic and vascular tissue engineering. Photochemical cross-linking is an emerging technique able to stabilize tissue grafts and improve the physicochemical properties of collagen-based structures. However, other important properties of collagen-based structures and the effect of processing parameters on these properties have not been explored. In this study, we aim to investigate the dose dependence of tensile and swelling properties on two parameters, namely, laser energy fluence and rose Bengal photosensitizer concentration. We also study the compression properties using cyclic compression test, long-term stability using subcutaneous implantation, and hematocompatibility using platelets adhesion test, of cross-linked collagen structures. Moreover, because limited optical penetration in turbid media is the major obstacle for light-based techniques, we also characterize the optical properties, which partially determine the effective optical penetration depth in collagen gel samples, during photochemical cross-linking. Laser energy fluence and rose Bengal concentration are important parameters affecting the cross-linking efficiency, which was characterized as the mechanical and the swelling properties, in a dose-dependent manner. Under the experimental conditions in this study, the peak fluence was 12.5 J/cm2 and the minimal rose Bengal concentration for effective cross-linking was >0.00008% (0.786 micromol). Photochemical cross-linking also enhanced the compression strength and long-term stability of collagen structures without compromising the tissue compatibility. Furthermore, photochemical cross-linking reduced platelet adhesion and abolished fibrin mesh formation, thereby improving the hematocompatibility of collagen structures. These results suggest the feasibility of using the photochemically cross-linked collagen structures for orthopedic and vascular tissue engineering. Finally, the effective optical penetration depth in collagen gel samples is wavelength and rose Bengal concentration dependent, and was approximately 12 mm at 514 nm at 0.001% (9.825 micromol), the rose Bengal concentration mostly used in this study.

Combined phacoemulsification and nonpenetrating deep sclerectomy in the treatment of chronic angle-closure glaucoma with cataract.

PURPOSE: To review the result of nonpenetrating deep sclerectomy (NPDS) combined with phacoemulsification in the treatment of chronic angle-closure glaucoma (CACG) with coexisting cataract. METHODS: This is a retrospective review of 29 eyes of 26 patients who had undergone combined NPDS and phacoemulsification for cataract and CACG between January 2001 and June 2003. The visual acuity, intraocular pressure (IOP), and complications were analyzed. RESULTS: The mean follow-up period was 33.8 months (range 23.3 to 54.0 months). Postoperative visual acuity improved in 21 eyes (72%) and remained the same in 6 eyes (21%). The IOP was reduced significantly from 20.3+/-3.9 mmHg (mean +/- SD) preoperatively to 15.9+/-3.1 mmHg postoperatively at last follow-up visit (p<0.001). The number of antiglaucoma medications was also reduced significantly from 2.9+/-0.8 (mean +/- SD) preoperatively to 1.0+/-1.2 at last follow-up (p<0.001). Fifteen eyes (52%) achieved complete success with IOP < or = 21 mmHg without antiglaucoma medications and 25 eyes (86%) achieved qualified success with IOP < or = 21 mmHg with or without medications at the last follow-up visit. Of the 25 eyes achieving qualified success, 24 (96%) had a reduction in the number of medications. There were 4 failures, defined as uncontrolled IOP requiring further filtering operation or oral drug treatment. Intraoperative complications included one accidental anterior chamber puncture and one iris plug intraoperatively. Postoperative complications included one choroidal effusion, three wound leaks requiring repair, and two punctate epithelial erosions. There was no shallowing of the anterior chamber, hyphema, hypotony, or infection encountered. CONCLUSIONS: Combined NPDS and phacoemulsification could be a safe and effective surgical option for the management of CACG with cataract.

Total ablation of paternal accessory sex glands curtails developmental potential in preimplantation embryos in the golden hamster.

The effects of total removal of paternal accessory sex glands (TX) on preimplantation embryonic development was studied in the golden hamster model. Cell numbers of the two groups of embryos did not differ up to 60 h p.c., but at 66 and 70 h p.c., each TX embryo has 2 and 3 cells less respectively (P<0.05, TX vs SH). At 70 h p.c., 46.6+/-4.4 of the TX embryos blastomeres were labelled with the terminal deoxynucleotide transferase - mediated dUTP-nickend-labelling technique, compared with 31.5+/-2.1 in the SH group (P<0.01, TX vs SH). No difference was found in the SDS-PAGE profiles of two-cell embryos from the two groups. An extra band corresponding to 136.5 kDa was consistently found in the four-cell TX embryos. The nascent proteins profiles of four-cell embryos from the two groups were similar. As the embryos progressed from two to four cells, the protein content decreased by 16% in the SH embryos (P<0.05) and 7% in the TX embryos. These observations suggest that total ablation of paternal accessory sex glands could result in developmental aberrations from the two-cell to morula stages and a higher incidence of apoptosis at 70 h p.c.

Study of microbial community of brewery-treating granular sludge by denaturing gradient gel electrophoresis of 16S rRNA gene.

The microbial community structure of granular sludge from an upflow anaerobic sludge blanket (UASB) reactor treating brewery effluent was studied by denaturing gradient gel electrophoresis (DGGE). Twelve major bands were observed in the DGGE fingerprint for the Bacteria domain and four bands for the Archaea domain. Of the bacterial bands observed, six were successfully purified and sequenced. Among them, three were related to the gram-positive low G + C group, one to the Delta subclass of the Proteobacteria, one to the Gamma subclass, and one to the Cytophaga group with no close related sequence. The 16S rRNA sequences of the four archaeal bands were closely associated with Methanosaeta concilii and Methanobacterium formicum.