Comparison of Prosthetic Materials in Incisional Hernia Repair

Purpose Incisional hernias are not uncommon after abdominal surgery, but their repair is associated with a high risk of complications, including adhesions and recurrence. Many different types of meshes and adhesion barriers have been developed in an attempt to overcome these problems, some of which we have assessed in a rat model.Methods We made a full-thickness 1.5 × 2.5-cm abdominal wall defect in 30 Sprague-Dawley rats, which were divided into three groups according to the materials used for repair: 2 × 3-cm polypropylene mesh (group 1); expanded polytetrafluoroethylene (PTFE) with double-layer polypropylene mesh (group 2); or polypropylene mesh with oxidized cellulose adhesion barriers (group 3). We assessed adhesion formation, tensile strength, and histopathologic findings.Results The mean adhesion scores were 3.3, 1.3, and 0.7, in groups 1, 2, and 3, respectively (P < 0.001). The area involved by adhesions was significantly greater in group 1 than in groups 2 or 3 (P < 0.01, P < 0.05), but there was no significant difference between groups 2 and 3 (P < 0.05). The tensile strength in group 2 was less than that in groups 1 or 3 (P < 0.01, P < 0.05), but there was no significant difference between groups 1 and 3 (P > 0.05).Conclusion Although there was less adhesion formation with PTFE and oxidized cellulose, PTFE not only impaired the tensile strength, but also induced fibrosis and inflammation. An oxidized cellulose adhesion barrier can be safely used in incisional hernia repair to prevent intra-abdominal adhesions.     

Antithrombin III attenuates pulmonary tissue injury caused by mesenteric ischemia-reperfusion

BACKGROUND: Mesenteric ischemia-reperfusion (I/R) is a well-known event causing both local and remote organ injuries, including the lungs. Recently, several studies indicated that activated leukocyte-endothelial cell interactions play an important role in the mechanisms of these injuries. As a natural inhibitor of serine proteases, antithrombin was shown previously to attenuate the tissue damage after local I/R in several organ systems. Here, we examined the effects of antithrombin on pulmonary injury after mesenteric I/R. METHODS: Wistar albino rats underwent median laparotomy and were randomized into 3 groups: (1) sham-operated control (n = 12), (2) 60 minutes of mesenteric ischemia and 3 hours of reperfusion (n = 12), and (3) antithrombin-pretreated (250 U/kg) group before the I/R (n = 12). At the end of reperfusion, animals were killed and neutrophil sequestration, myeloperoxidase (MPO) activity, and Evans blue dye extravasation in the lung parenchyma were assessed and compared. RESULTS: There was a statistically significant increase in the quantity of Evans blue dye concentration, leukocyte sequestration, and MPO activity in the I/R group when compared with the control group. The pretreatment of animals with antithrombin significantly decreased the pulmonary injury characterized by increased Evans blue dye extravasation, leukocyte sequestration, and MPO activity. CONCLUSION: The data of the present study suggest that mesenteric ischemia and reperfusion induces pulmonary injury characterized by activated neutrophil sequestration and increased microvascular leakage in the lungs. A significant attenuation of intestinal I/R-related lung injury with the use of antithrombin concentrate warrants further studies to elucidate the potential role of this natural serine protease inhibitor in clinical settings.     

Measuring the correlation between adenoidal-nasopharyngeal ratio (AN ratio) and tympanogram in children

OBJECTIVE: To evaluate the correlation between adenoidal-nasopharyngeal ratio (AN ratio) and tympanogram in children. STUDY DESIGN: A prospective clinical study from June 2002 to May 2003. METHOD: A total of 64 children, aged 6-9 years who presented with nasal obstruction, snoring, mouth breathing, and hyponasal speech were examined and AN ratio was calculated by using the lateral neck radiograms and compared with the tympanometric values. The relationship between AN ratio and middle-ear pressure was evaluated, regarding the AN ratio of 0.71. The chi-square test was used to analyze the correlation between AN ratio and middle ear pressures and Wilcoxon test was used to compare the changes between the mean AN ratio values, and mean middle ear pressures (including A and C type tympanograms) before and after medical therapy. RESULTS: Middle-ear effusions and C type tympanograms in impedance audiometry were both related to eustachian tube dysfunction resulting from enlargement of the adenoids with AN ratios higher than 0.71. Middle ear pressures were found lower in children with AN ratio greater than 0.71 than in children AN ratio less than 0.71 and the difference was highly significant (p<0.001). Although medical treatment of large adenoids was rather effective to shrink the adenoid tissue (p<0.001), it did not cause a statistically significant change in tympanometric values (p>0.05). CONCLUSIONS: Antibiotherapy is effective in reducing adenoid size without signs and symptoms of infection. The reduction of the adenoids in size after 3 weeks of antibiotherapy has an positive effect on recovery of eustachian tube function but is not sufficient in patients with middle ear effusion. Early ventilation tube insertion may be an alternative therapy for the middle ear effusions not improving by 3 weeks medical therapy.     

Treatment of a cervical viable pregnancy with a single intraamniotic methotrexate injection: a case report

Introduction. Cervical pregnancy is a rare condition, constituting <1% of all ectopic pregnancies. Case report. We report here, the successful management of a viable 7 weeks gestation cervical pregnancy. Feticide with 2 ml of potassium chloride 15% was performed under the guidance of transvaginal ultrasonography. Then 70 mg methotrexate (50 mg/m²) was injected through this spinal needle in to the amniotic cavity. Also serial changes in the color Doppler imaging after the methotrexate injection were emphasized.     

Indocyanine Green Alters Transepithelial Electrical Parameters of the Distal Colon

Indocyanine green (ICG) is used as a dye marker of the vascular space in gastroenterology, ophthalmology, neurology, and critical care medicine. It is widely regarded to be inert. We report, however, that ICG demonstrates effects on colonic transepithelial electrical parameters which could form a basis for a growing number of deleterious gastrointestinal and other clinical effects. Short-circuit current (Iscc), transepithelial conductance (gt), and transepithelial paracellular flux of 14C-D-mannitol were monitored across sheets of rat distal colon. Dye was introduced to mucosal or serosal tissue surfaces at a concentration similar to that used in vivo (10 microg/ml). ICG decreased Iscc by over 50% and gt by over 10%. Transepithelial mannitol flux was not altered. Dye was effective only from the serosal surface. Cyclic AMP-induced spiking of Iscc was not affected by ICG. Preincubation with amiloride or furosemide did not affect the action of the dye on gt or Iscc. ICG at in vivo dosages is clearly capable of inhibiting ion transport across colon epithelial tissue. The serosal site of action indicates activity on a basal-lateral transport system or diffusion into the cell only across the basal-lateral membrane followed by inhibition of a transporter from the intracellular side. ICG should not be considered inert in vivo. Leakage of ICG from the vascular space into the interstitial fluid space will likely result in tissue morbidity.     

Efficacy of anti-adhesive barriers in secondary thyroidectomy: an experimental study

HYPOTHESIS: This study was conducted to compare the effectiveness of two anti-adhesive barriers (Seprafilm and Interceed) for reducing adhesions after thyroidectomy in a rat model. The anti-adhesive barriers are suggested for use in repeated surgeries in general and the gynecologic fields in particular. STUDY DESIGN: Controlled, randomized study. METHODS: Twenty-eight male Wistar Albino rats that underwent right subtotal thyroidectomy were randomly assigned to three groups. One group received Seprafilm (n = 10), and the other received Interceed (n = 10) as anti-adhesive barriers. The third group was the control group (n = 8). At postoperative day 14, the rats were killed under general anesthesia, and the surgical fields were evaluated for the adhesion formation. The extent of the adhesion formation is scored from 0 (no adhesions) to 2 (fibrous adhesions that required sharp dissection). Histopathologically, chronic inflammation, histiocyte, fibroblast, fibrosis, collagen, vascularization, granuloma, giant cell, and fat necrosis were examined. RESULTS: All the subjects in the control group, 7 of 10 in the Interceed group, and 4 of 10 in the Seprafilm group needed to be dissected bluntly or sharply. There was significant difference between the Seprafilm and the control group (P < .05) whereas there was no significant difference between the Interceed group and the control group (P > .05). When examined histopathologically, the criteria showing adhesion, such as fibrosis, fibroblast, and collagen were higher in the control group compared with the Seprafilm and Interceed groups. There was no significant difference between the Seprafilm and Interceed groups, whereas a significant difference was found between these two groups and the control group. CONCLUSION: This study suggests that both Seprafilm and Interceed decrease the incidence of posthyroidectomy adhesions in a rat model. Both agents showed no foreign body reaction.     

Psychosocial correlates of substance use among adolescents in Mersin, Turkey

The objective of this study was to determine the effects of psychosocial factors such as peer group, family and academic self-perception on smoking, alcohol and substance use by adolescents living in Mersin, Turkey. The study included a total of 3282 students from the sixth and tenth grades and college. The number of participating students required from each school was obtained through stratification, and by weighing the enrolled student population in each subgroup. The final sample was derived using a simple random sampling technique. A 45-item self-administered questionnaire was used. The questionnaire included questions about socio-demographic characteristics and lifetime and current (i.e. within the past month) use of cigarettes, alcohol, cannabis, inhalants and other illicit drugs (heroin, cocaine, sedative-hypnotic drugs, etc.). This study found that: (1) higher socio-economic status of the family increased the likelihood of smoking and alcohol use in adolescents; (2) the prevalence of alcohol use was higher in adolescents whose mothers had a higher educational level and whose mothers and fathers drank alcohol; (3) there was a significant association between substance use and having a peer who used a substance; and (4) the prevalence of smoking was significantly higher in students who perceived their academic performance to be poor. Understanding the role and importance of psychosocial factors associated with smoking, alcohol and substance use will be crucial to develop preventive measures for adolescents.     

Simultaneous blockade of platelet-derived growth factor-receptor and epidermal growth factor-receptor signaling and systemic administration of paclitaxel as therapy for human prostate cancer metastasis in bone of nude mice

Once prostate cancer metastasizes to bone, conventional chemotherapy is largely ineffective. We hypothesized that inhibition of phosphorylation of the epidermal growth factor receptor (EGF-R) and platelet-derived growth factor receptor (PDGF-R) expressed on tumor cells and tumor-associated endothelial cells, which is associated with tumor progression, in combination with paclitaxel would inhibit experimental prostate cancer bone metastasis and preserve bone structure. We tested this hypothesis in nude mice, using human PC-3MM2 prostate cancer cells. PC-3MM2 cells growing adjacent to bone tissue and endothelial cells within these lesions expressed phosphorylated EGF-R and PDGF-R alpha and -beta on their surfaces. The percentage of positive endothelial cells and the intensity of receptor expression directly correlated with proximity to bone tissue. Oral administration of PKI166 inhibited the phosphorylation of EGF-R but not PDGF-R, whereas oral administration of STI571 inhibited the phosphorylation of PDGF-R but not EGF-R. Combination therapy using oral PKI166 and STI571 with i.p. injections of paclitaxel induced a high level of apoptosis in tumor vascular endothelial cells and tumor cells in parallel with inhibition of tumor growth in the bone, preservation of bone structure, and reduction of lymph node metastasis. Collectively, these data demonstrate that blockade of phosphorylation of EGF-R and PDGF-R coupled with administration of paclitaxel significantly suppresses experimental human prostate cancer bone metastasis.