Simulated graft recession in endoscopic ACL reconstruction: influence on graft strain

Eight fresh cadaveric knee specimens underwent arthroscopic-assisted ACL reconstruction to examine the influence of femoral graft recession on graft strain pattern. Length changes between tibial origin and femoral insertion (simulating graft strain or isometry pattern) were measured throughout knee motion (0 degrees-90 degrees) with a simulated ACL construct. Measurements were taken at the "endo" position (replicating the normal endoscopic position) and in progressive 1.5-mm increments proximally within the femoral tunnel (mimicking femoral graft recession). After recession up to a maximum of 15 mm, a block was placed anterior to the "recessed" graft construct (simulating placement of bone graft anterior to the recessed graft) and strain patterns were remeasured. Graft strain patterns were altered with as little as 1.5 mm recession in two of eight specimens. Compared to the "endo" position, all specimens showed a statistically significant decrease in strain by 3 mm of graft recession (P<.001 for 7 of 8, and P=.0138 for 1 of 8). A direct relationship exists between graft placement and ACL strain patterns, with more proximal graft "recession" adversely influencing normal graft strain. Bone graft placement anterior to the recessed graft restores strain patterns to those seen at the normal "endoscopic" position.     

Loss of tumor-promoting activity of unleaded gasoline in N- nitrosodiethylamine-initiated ovariectomized B6C3F1 mouse liver

Unleaded gasoline (UG) vapor (2056 ppm) increased the incidence of liver tumors in a chronic bioassay and exhibited tumor-promoting activity in N-nitrosodiethylamine (DEN)-initiated female mouse liver. Estrogen inhibited mouse liver tumor development and the hepatocarcinogenic and tumor-promoting dose of UG produced uterine changes suggestive of estrogen antagonism. To directly test the hypothesis that UG-induced tumor-promoting ability is secondary to its interaction with the mouse liver tumor inhibitor, estrogen, we compared the tumor-promoting ability of UG in ovariectomized (Ovex) mice with the hepatic tumor-promoting ability of UG in intact mice. Ovaries were surgically removed at 4 weeks of age. Exposure to wholly vaporized UG (2018 ppm) under bioassay and tumor-promoting conditions began at 8 weeks of age. After 4 months of exposure, UG increased relative liver weight and hepatic microsomal cytochrome P450 pentoxyresourfin-O- dealkylase and ethoxyresorufin-O-deethylase activity to a similar extent in intact and Ovex mice. Non-focal hepatocyte proliferation, as measured by the incorporation of bromo-deoxyuridine, was not changed by UG exposure and was similar in all treatment groups. After 4 months of exposure to DEN-initiated mice, UG significantly increased the volume fraction of liver occupied by foci (three-fold) as compared to control intact mice. As expected, volume of foci was elevated in DEN/Ovex/control mice as compared to DEN/intact/control mice. In DEN/Ovex mice UG did not significantly increase the focal volume fraction. Thus, the tumor promoting activity of UG, as demonstrated by increased volume fraction of liver occupied by hepatic foci in intact mice, is greatly attenuated in Ovex mice. The volume fraction data in Ovex mice support the hypothesis that the tumor promoting activity of UG is dependent upon the interaction of UG with ovarian hormones. These data also indicate that hepatic microsomal cytochrome P450 PROD and EROD induction, hepatomegaly and non-focal hepatic LI are not specific markers of hepatic tumor promoting activity of UG.      

Chemoprevention of spontaneous tumorigenesis in nullizygous p53- deficient mice by dehydroepiandrosterone and its analog 16alpha-fluoro- 5-androsten-17-one

Transgenic mice with both alleles of the p53 tumor suppressor gene product 'knocked out' by gene targeting are susceptible to early development of tumors, chiefly lymphomas and sarcomas. Compared with the control group, administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male p53-deficient mice extended their lifespan by delaying death due to neoplasms (from 105 to 166 days on study, P = 0.002), primarily by suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P = 0.010). Treatment with a synthetic DHEA analog, 16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet also increased lifespan, to 140 days for mice that developed tumors (P = 0.037). The effects of these steroids on lifespan and tumor development did not appear to be strongly related to inhibition of food consumption and weight gain, in that a group pair-fed with control diet to the reduced food consumption of the DHEA-treated group developed and died of the same types of neoplasms at the same rate as the controls fed ad libitum. The chemopreventive effect of these steroids has been proposed to be due to suppression of DNA synthesis by inhibition of glucose 6-phosphate dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway. Although DHEA and its analog are strong non- competitive inhibitors of this enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide pools in the liver, as would have been predicted. The chemopreventive effect of DHEA in this model may be due to steroid-induced thymic atrophy and suppression of T cell lymphoma, permitting these mice to survive long enough to develop tumors with longer latency.      

Mitomycin-C induced hemolytic uremic syndrome: a case report and literature review

Hemolytic uremic syndrome spontaneously arises in a few patients with advanced cancer, but it is more commonly related to the use of certain chemotherapeutic agents. Mitomycin-C is, etiologically, the most common causative agent inducing hemolytic uremic syndrome, in a dose dependent manner. We report this syndrome, attributable to mitomycin-C at a cumulative dose of 40 mg/m2, in a gastric cancer patient. A 42-year-old female with stage III gastric cancer underwent radical gastrectomy and was given mitomycin-C at 10 mg/m2 intravenously every four weeks as adjuvant therapy. Hemolytic uremic syndrome was diagnosed three months after the last dose of mitomycin-C administration. The most prominent symptoms included pallor, hypertension and anasarca, with laboratory evidence of microangiopathic hemolytic anemia, azotemia and hyperkalemia. Her disease was progressive, but fortunately stabilized after staphylococcus column A dialysis. Her disease remained in remission for 24 months from the time of diagnosis, and then relapsed in the form of peritoneal carcinomatosis with partial intestinal obstruction.      

Primary syphilis of oral mucosa: case report of an unusual manifestation.

Dental clinicians and other health care providers have long been concerned about a variety of infectious agents that may be transmitted within the dental setting. Many infectious diseases, including human immunodeficiency virus, hepatitis, tuberculosis, and syphilis are important both because of their potential transmissibility and because the first manifestations of the disease may appear in the oral cavity. Oral disease as a consequence of primary syphilis is rare. This article details a patient presenting with a labial nodule as her only clinical manifestation of undiagnosed primary syphilis.     

Modifying the two-stage cleft palate surgical correction.

OBJECTIVE: This paper reports the experience with a two-stage approach to surgical correction of the complete cleft palate, wherein timing of the second stage is dependent on the judgment of the speech pathologist and the orthodontist together with the surgeon. PATIENTS: Of a total of 35 patients having complete unilateral clefts a sample of 22 were available for postsurgical assessment. The first-stage repair of the palate was carried out at an average age of 10.7 months (range 6 to 17 months), and the second-stage repair of the residual cleft was completed at an average age of 32.7 months (range 26 to 34 months). INTERVENTIONS: The first-stage repair of the soft palate defect involved mobilizing two short posteriorly based flaps, which extend onto the posterior quarter of the hard palate thus including up to 1 cm of mucoperiosteum. Careful freeing of the muscle is followed by an intravelar veloplasty. The later closure of the residual cleft involved turnover hinge flaps and small mucoperiosteal flaps. RESULTS: Eighty-seven percent of the sample had good to excellent speech as assessed by the Great Ormond Street screening method. Only two patients showed evidence of recessive maxillae with Class III malocclusions. CONCLUSIONS: A two-stage surgical closure of the palate using this procedure would appear to confer several valuable advantages to the patient. These include favorable outcomes for speech in the large majority of cases and minimal adverse effects on the growth of the midface region.     

Mine Blast Injuries - Our Experience

Background

The sudden increase in incidence and magnitude of mine blast injuries prompted us to highlight the problem and its management.

Methods

The cases of mine blast injuries occurring during mining and demining in a particular geographical area were analysed. Total 27 cases of mine blast injuries occurred during mining or demining operations in a period of 13 months.

Results

Various body regions were involved in the mine blast injuries but the main brunt was borne by feet and legs followed by multiple body regions due to splinters. 14 patients underwent below knee (BK) amputation while 4 patients required through knee (TK) amputations. The effect of blast was so severe that most of the cases required 2 to 5 times wound debridements. The initial aggressive debridement / open stump amputation saved the limb and life of all patients.

Conclusion

A mine blast causes extensive injuries and psychological trauma. Management is needed urgently, surgery is difficult, and amputation is often inevitable. Maximum lives and limbs can be saved with aggressive debridement, repeated inspections and dressings under anaesthesia and definitive closure at optimum time.Key Words: Amputation, Antipersonnel mine, Crush syndrome, Debridements, Mine blast injury, Secondary missiles, Shrapenels     

Wound healing of laparoscopic esophageal myotomy with or without an added gastric patch

Background: The purpose of this research is to compare the wound healing of the laparoscopic esophagomyotomy with and without a gastric patch. Methods: Twelve male pigs were distributed into two groups of six animals. Esophagomyotomy was performed in group A. A gastric patch was associated to the myotomy in group B. On the 21^st postoperative day, lumen molding was accomplished to determine the index of stenosis (IS) at the area of myotomy (AM). Macroscopic and microscopic aspects of wound healing were also studied at AM. Three microscopic morphologic patterns were defined for morphometric evaluation: leukocytes (constituted by polymorphonuclear and mononuclear cells), new endothelial cells, and collagen fibers. Results: There was a longer operative duration in group B (93.6 min) than in group A (45 min). At AM, IS was negative (lumen increased) and equivalent in both groups: −11.1% in group A and −12.7% in group B. Mesotelial epithelium covering RM was observed in group A. Inflammatory reaction was greater in group B in comparison with group A (leuCocytes: 22 cells versus 8.6; fibrosis: 25.5 fibers versus 15.6; granulation tissue: 18.7 vessels versus 9.7). Conclusion: Esophagomyotomy followed by gastric patch does not heal adequately and is worsened by the presence of foreign body granulomas around stitches. Myotomy without gastric patch is faster and causes lower inflammation. Myotomy alone or with gastric patch does not lead to esophageal stenosis at RM and does not lead to restoration of the esophageal musculature continuity.     

Histological analysis of the periapical tissues of dog deciduous teeth after root canal filling with diferent materials

The problem of finding an ideal material for filling root canals of deciduous teeth has not been solved yet. This fact led to the development of an experiment to histologically analyze the periapical tissue reaction to 3 root canal filling materials. Eighty root canals of dog deciduous anterior teeth from 6 animals, 60 days old, were used in this study. After biomechanical preparation, the root canals were filled with the following materials: slowly resorbable Maisto paste, Sealer 26 with iodoform, L&C paste (calcium hydroxide with olive oil) and as a control group, canals that were prepared but not filled. At thirty days after the treatment the animals were killed and the teeth prepared for histological analysis. The materials were ranked statistically from the best to the worst as follows: a - Maisto paste, b - Sealer 26 with iodoform, c - control group, d - L&C paste. There was significant difference (p = 0.01) only when the results of the other groups were compared with the L&C paste group. It was also observed that L&C paste was not biologically compatible and that the other materials were biocompatible but their resorption was not at the same rate as that of the deciduous teeth roots.