Lichtenstein technique for inguinal hernia repair using polypropylene mesh fixed with sutures vs. self-fixating polypropylene mesh: a prospective randomized comparative study.

PURPOSE: Chronic postoperative pain is probably the most significant complication of tension-free inguinal hernia repair as its presence can considerably affect the life quality of the patient. Different mesh materials and different surgical techniques for mesh fixation have been applied to reduce chronic postoperative pain, with controversial, nevertheless, results. The aim of this prospective randomized study was to evaluate the effect of a relatively new mesh with self-fixating properties, used to repair inguinal hernia with the Lichtenstein technique, on early and chronic postoperative pain. METHODS: Between June 2009 and June 2010, 50 patients with primary unilateral inguinal hernia were treated using the Lichtenstein technique. Patients were randomly assigned to receive either a polypropylene mesh, fixed with polypropylene sutures (n = 25; group A), or a self-fixating polypropylene mesh with resorbable polylactic acid microgrips (n = 25; group B). Demographic data were recorded. Early and chronic postoperative pain was evaluated using the visual analog scale (VAS). Duration of surgery, complications, length of hospitalization and recurrence were also recorded. RESULTS: No statistical difference was found between the two groups in association to demographic data. Operating time was 53.4 ± 12.5 and 44.4 ± 7.2 min in groups A and B, respectively, and the difference was statistically significant (p < 0.001). No difference was observed between the groups regarding the postoperative complications. The VAS of early postoperative pain was 1.7 ± 1.9 in group A and 1.3 ± 1.6 in group B, with the difference being not statistically significant (p = 0.21). Concerning chronic pain, no remarkable statistically significant difference was observed between the two groups at 3-month, 1- and 2-year follow-up period. At the end of the study, no recurrence was reported in either group. CONCLUSIONS: Self-fixating mesh can be safely and effectively used in inguinal hernia repair with the additional advantage of reducing the operative time compared to the classic Lichtenstein technique. However, its use is not accompanied by reduced rates in early or chronic postoperative pain.

Dielectric and conductivity measurements as proxy method to monitor contamination in sandstone.

The present work investigates whether dielectric spectroscopy can be used to detect contamination, which may leach in a natural porous material, due to the spreading of contaminants. For this purpose, dielectric and conductivity measurements, in the frequency range from 10 mHz to 1 MHz, were carried out in sandstone samples, partially filled or saturated with solutions of leachates, at different concentrations. The experimental results suggest the dominant role of free water to the measured electrical conductivity and dielectric permittivity in contaminated samples with high water content. On the other hand, various relaxation mechanisms were observed in dried samples at different leachate concentrations. Experimental data were fitted using the Havriliak-Negami dielectric relaxation function, superimposed with a conductivity term. The determined parameters of the fitting function may serve to distinguish between different amounts of leachate in sandstone samples.

Appendiceal mucocele. a retrospective analysis of 19 cases.

BACKGROUND: Appendiceal mucocele is an infrequent well-recognized entity that can present in a variety of clinical syndromes or can be asymptomatic and discovered incidentally. PATIENTS AND METHODS: Nineteen patients with a diagnosis of primary appendiceal mucocele treated in our institution between January 1, 1987 and December 31, 2006 were included in this retrospective analysis. RESULTS: The histological examination of the specimens revealed simple and hyperplastic appendiceal mucocele in nine cases (47%), mucinous appendiceal cystadenoma in eight cases (42%), and mucinous appendiceal cystadenocarcinoma in two cases (11%). Thirteen patients (68%) underwent appendectomy, five patients (26%) right colectomy, and two patients (6%) underwent right colectomy for invasive appendiceal cystadenocarcinoma and at the same time right nephrectomy and sigmoidectomy, respectively, for concomitant malignancy. CONCLUSION: Mucocele of the appendix may be related to a benign or malignant appendiceal process, leading to individualized diagnosis and treatment.

Adrenal pseudocyst presenting as acute abdomen during pregnancy.

Pseudocysts of the adrenal gland are rare lesions, which are usually discovered as incidental findings. Since they are in the majority of cases non-functioning, they become symptomatic only when they are complicated with rupture, haemorrhage or infection. We present a case of a 28-year-old woman in the 26th gestational week, who developed an acute abdomen due to a haemorrhagic pseudocyst of the left adrenal. The patient was submitted to left adrenalectomy. The described case is the third reported case of cystic adrenal lesion discovered during pregnancy and only the first reported case of acute presentation of an adrenal pseudocyst during pregnancy.

Tension-free repair versus modified Bassini technique (Andrews technique) for strangulated inguinal hernia: a comparative study.

BACKGROUND: To compare tension-free hernia repair to a modified Bassini technique (Andrew's technique) used to treat complicated inguinal hernia. METHODS: In the period 1990-2004, 75 patients were submitted to emergency operation because of strangulated inguinal hernia. 33 patients underwent tension-free repair utilizing a polypropylene mesh (group A), whereas the remaining 42 patients underwent a modified Bassini technique (group B). RESULTS: Mean operative time was significantly longer for group B (91.5+/-9.3 min vs 75.7+/-10.5 min, p<0.05). Postoperative hospital stay was also significantly longer in group B compared to group A (10.3+/-3.4 days vs 4.5+/-2.1 days, p<0.01). Postoperative complication rate did not differ significantly between the two groups (5/33, 15.1% vs 5/42, 11.9%, p=n.s.). No mesh had to be removed. At follow-up (mean 9+/-4.2 years), there was one recurrence in group A (1/33, 3%) and two recurrences in group B (2/42, 4.7%) (p=n.s.). CONCLUSION: The presence of a strangulated inguinal hernia cannot be considered a contraindication for the use of a prosthetic mesh.

Surgical management of cecal diverticulitis: is diverticulectomy enough?

INTRODUCTION: Cecal diverticulitis is a rare condition in the western population. The optimal management of this condition is still controversial, ranging from conservative antibiotic treatment to aggressive resection. We present our experience of the surgical management of eight cases of cecal diverticulitis over a 25-year period. PATIENTS AND METHODS: The mean age of the patients was 54.2 years. Five patients underwent diverticulectomy, 2 patients underwent ileocecal resection, and 1 patient underwent suture of the perforated diverticulum. RESULTS: The postoperative course of all patients was uneventful. At long-term follow-up (mean 14.6 years, range 1-25 years) none of the patients who underwent diverticulectomy, mentioned any symptom or complication. CONCLUSION: We conclude that diverticulectomy, if technically feasible, could be considered as adequate therapy for cecal diverticulitis. Aggressive resection should be considered in cases of extensive inflammatory changes.

Functional capacity of the thyroid autograft: an experimental study.

BACKGROUND: The aim of this study was to investigate the functional capacity of thyroid autografts after total thyroidectomy in a rabbit model. MATERIAL AND METHODS: Thirty-eight rabbits underwent total thyroidetomy. One of the two thyroid lobes was cut into 1-mm pieces and was introduced intramuscularly into the right quadriceps muscle (group A, n = 10), the right rectus abdominalis muscle (group B, n = 10), and the right sacrodorsalis muscle (group C, n = 10). Another group of 8 rabbits underwent total thyroidectomy without autologous implantation and served as the control group (group D). The animals were observed for 8 weeks with weekly measurements of thyroid hormones. At the end of the 8th week, a scintigram was performed. The autografts were removed 2 days later. RESULTS: The thyroid hormone levels showed a gradual decrease until the 2nd-5th week after implantation, followed by a gradual increase and establishment of euthyroid levels between the 5th and 8th weeks. Respectively, an increase of thyreotropin hormone was noted with maximal values in the 4th week, followed by a gradual decrease until the end of the 8th week. The scintigram at the end of the 8th week revealed the presence of functional thyroid tissue in all cases. Functional thyroid follicles were found in all animals who survived. In 35.7% of the autografts, we noted the development of fibrous tissue and gigantocytic granulomas in the periphery, which could be interpretated as a "foreign body" reaction. CONCLUSION: Thyroid autografts can completely substitute thyroid function after total thyroidectomy.

Comparison between modern mesh and conventional non-mesh methods of inguinal hernia repair.

BACKGROUND: The objectives of the study were to compare the tension-free mesh repair with non-meash conventional repair of groin hernia. METHODS: In the past two years in 299 consecutive unselected patients 339 inguinal hernia repairs were carried out. They randomly allocated to undergo either a non-meash modified Bassini's repair (n=164) or a tension-free mesh repair (n=175). The latter group consisted of laparoscopic TAPP repair (n=46) and open onlay patch repair (n=64) or plug and patch repair (n=65). Operation time, postoperative pain and complications, hospital stay, return to work and recurrence were assessed. Statistical analysis was made using the "t"-Student test. RESULTS: The characteristics of the patients in each group and the operation time did not differ significantly. The planned procedure was completed in all and no death occurred. The analgesic requirements (none 2.5 vs 56.4%, opiods 77 vs 23.6%), complication rate (9.4 vs 4.3%), hospital stay (4.2 vs 1.8 days), return to work (17.2 vs 7.3 days) and recurrence rate (5.5 vs 1.2%) in non-mesh group were more than in the mesh group. All differences were statistically significant (p<0.05). Among the three subgroups of mesh group no statistically significant differences (p>0.05) were found. CONCLUSIONS: The tension-free mesh repair either open or laparoscopic provides excellent results with better short-term outcome and lower recurrence rate than non-mesh modified Bassini's repair.

Complete dehiscence of the abdominal wound and incriminating factors.

OBJECTIVE: To find out the causes of abdominal wound dehiscence. DESIGN: Retrospective study. SETTING: University hospital, Greece. SUBJECTS: Abdominal wound dehiscence occurred in 89 cases out of 19,206 major abdominal operations including 4671 emergencies during the past 15 years (0.5%). INTERVENTIONS: In the study group 14 local and systemic risk factors were analysed and compared with those in a control group of 89 patients who had similar procedures without dehiscence. MAIN OUTCOME MEASURES: Statistical analysis using the chi square test. RESULTS: Significant factors (p < 0.05) included age over 65 years, emergency operation, cancer, haemodynamic instability, intra-abdominal sepsis, wound infection, hypoalbuminaemia, ascites, obesity, and steroids. Risk factors that were not significant included sex, anaemia, diabetes mellitus and pulmonary disease. Overall morbidity and mortality were 30% and 16%, respectively. The mortality and the possibility of dehiscence seem to correlate directly with the number of risk factors. CONCLUSION: Patients with these risk factors require more attention and special care to minimise the risk of its occurrence.

MR imaging of myositis ossificans: variable patterns at different stages.

Five patients with a palpable mass at presentation underwent magnetic resonance (MR) imaging. The final diagnosis was myositis ossificans (MO). MR imaging features, particularly after injection of gadopentetate dimeglumine, mimicked those of an inflammatory mass or neoplasm. The lesions were excised in three patients, and the images were correlated with histologic findings. Three different appearances were noted on MR images, corresponding to the stages of maturation of MO. Two cases involved early-stage lesions, and T1-weighted MR images showed a mass with homogeneous intermediate signal intensity. Both lesions showed rim enhancement after contrast agent injection and high signal intensity on T2-weighted images. Pathologic specimens demonstrated stroma with masses of spindle cells in which osteoid production was interspersed. The enhanced rim of the lesion mimicked the expected MR appearance of an abscess or necrotic tumor. Areas of enhancement in adjacent muscle were also seen on postcontrast T1-weighted images. Intermediate-stage MO was present in one case; there was evidence of a thin rim of calcification on plain radiographs and fatty changes in the lesion on T1-weighted images, corresponding with histologic findings. One case of a mature lesion showed a considerable degree of peripheral calcification both on MR images and at histology. MR imaging is nonspecific in the diagnosis of early-stage MO.

Implications of Tn5-associated adjacent deletions.

The prokaryotic transposable element Tn5 has been found to promote the formation of adjacent deletions. The frequency of adjacent deletion formation is much lower than that of normal transposition events. Like normal transposition, however, adjacent deletion formation requires the activity of the transposase protein. The deletions can be divided into two classes, as distinguished by their endpoints. The occurrence of one of the two deletion classes is increased when the frequency of normal transposition is reduced by the introduction of a deletion or a certain base substitution at one of the two outside ends (OEs). The nature of the base substitution at the mutant OE influences the class of deletion found adjacent to the wild-type OE, even though these two ends are about 12 kbp apart. By studying the formation of these deletions, we have gained some insight into the way in which the transposase interacts with the OEs. Our observations suggest that there is a protein-mediated interaction between the two ends, that different end base pairs are involved in different transposition-related processes, and that the adjacent deletions are the result of nonproductive attempts at transposition.

Induction of the SOS response in Escherichia coli inhibits Tn5 and IS50 transposition.

In response to DNA damage or the inhibition of normal DNA replication in Escherichia coli, a set of some 20 unlinked operons is induced through the RecA-mediated cleavage of the LexA repressor. We examined the effect of this SOS response on the transposition of Tn5 and determined that the frequency of transposition is reduced 5- to 10-fold in cells that constitutively express SOS functions, e.g., lexA(Def) strains. Furthermore, this inhibition is independent of recA function, is fully reversed by a wild-type copy of lexA, and is not caused by an alteration in the levels of the Tn5 transposase or inhibitor proteins. We isolated insertion mutations in a lexA(Def) background that reverse this transposition defect; all of these mapped to a new locus near 23 min on the E. coli chromosome.

Integration host factor plays a role in IS50 and Tn5 transposition.

In Escherichia coli, the frequencies of IS50 and Tn5 transposition are greater in Dam- cells than in isogenic Dam+ cells. IS50 transposition is increased approximately 1,000-fold and Tn5 transposition frequencies are increased about 5- to 10-fold in the absence of Dam methylation. However, in cells that are deficient for both integration host factor (IHF) and Dam methylase, the transposition frequencies of IS50 and Tn5 approximate those found in wild-type cells. The absence of IHF alone has no effect on either IS50 or Tn5 transposition. These results suggest that IHF is required for the increased transposition frequencies of IS50 and Tn5 that are observed in Dam- cells. It is also shown that the level of expression of IS50-encoded proteins, P1 and P2, required for IS50 and Tn5 transposition and its regulation does not decrease in IHF- or in IHF- Dam- cells. This result suggests that the effects of IHF on IS50 and Tn5 transposition are not at the level of IS50 gene expression. Finally, IHF is demonstrated to significantly retard the electrophoretic mobility of a 289-base-pair segment of IS50 DNA that contains a putative IHF protein-binding site. The physiological role of this IHF binding site remains to be determined.

Orientation of IS50 transposase gene and IS50 transposition.

Reversal of transposase gene orientation with respect to the nonidentical ends of IS50 strongly decreased IS50 transposition in both Dam- and Dam+ hosts. In either orientation, IS50 transposase expression was unaffected. These effects were independent of the surrounding DNA context. This shows that the efficiency of IS50 transposition is dependent on transposase gene orientation. The transposition frequencies of transposons utilizing inverted IS50 inside ends (IE), IE-IE transposons, were lower than either outside end (OE)-IE or OE-OE transposons.

Inosine induced mutations.

Two complementary 24 base single stranded oligonucleotides containing randomly located inosine residues were synthesized in vitro. Once annealed, the two oligonucleotides were cloned into derivatives of ColE1 and transformed into Escherichia coli. Sequence analysis of 157 clones yielded 305 mutations. The pattern of the mutations revealed the following: (1) The frequency of inosine induced mutations was significantly less than predicted from its content in the oligonucleotides; (2) Inosine incorporation resulted almost exclusively in base changes to guanine; (3) The mutation distribution is biased towards A/T to G/C substitutions; (4) There were reproducible position biases; and (5) There was a reproducible strand bias which was independent of the cassette orientation with respect to the plasmid origin of replication.

Mutational analysis of insertion sequence 50 (IS50) and transposon 5 (Tn5) ends.

Insertion sequence 50 (IS50) transposition utilizes a 19-base-pair "outside" end and a 19-base-pair "inside" end in inverted orientation relative to each other, whereas transposon 5 (Tn5) transposition utilizes two inverted outside ends. The frequency of transposition events that involve an inside end is regulated 1000-fold by the host dam methylase system. The end sequence requirements for transposition and its regulation by dam methylase were analyzed in Escherichia coli by generating random single base pair mutations in either an IS50 inside end or outside end placed in inverted orientation with respect to an unmutagenized outside end. The mutations were then isolated, assayed for transposition phenotype, and sequenced. Mutations were isolated at 15 of the 19 sites in the outside end. All of these mutations except those at position 4 decreased transposition. Mutations at position 4 (which is the only nonidentical base pair in a region of homology between the outside and inside ends) had no effect on transposition. Mutations were isolated at 11 of the 19 sites in the inside end. All of these mutations, including one at position 4, decreased transposition in dam- cells. Mutations at position 10 (within a dam recognition sequence) and 2 (not within a dam recognition sequence) reduced the magnitude of dam regulation. A mutation within a dam recognition sequence adjacent to the required 19 base pairs of the inside end did not reduce the magnitude of dam regulation.