Cadherin composition and multicellular aggregate invasion in organotypic models of epithelial ovarian cancer intraperitoneal metastasis.

During epithelial ovarian cancer (EOC) progression, intraperitoneally disseminating tumor cells and multicellular aggregates (MCAs) present in ascites fluid adhere to the peritoneum and induce retraction of the peritoneal mesothelial monolayer prior to invasion of the collagen-rich submesothelial matrix and proliferation into macro-metastases. Clinical studies have shown heterogeneity among EOC metastatic units with respect to cadherin expression profiles and invasive behavior; however, the impact of distinct cadherin profiles on peritoneal anchoring of metastatic lesions remains poorly understood. In the current study, we demonstrate that metastasis-associated behaviors of ovarian cancer cells and MCAs are influenced by cellular cadherin composition. Our results show that mesenchymal N-cadherin-expressing (Ncad+) cells and MCAs invade much more efficiently than E-cadherin-expressing (Ecad+) cells. Ncad+ MCAs exhibit rapid lateral dispersal prior to penetration of three-dimensional collagen matrices. When seeded as individual cells, lateral migration and cell-cell junction formation precede matrix invasion. Neutralizing the Ncad extracellular domain with the monoclonal antibody GC-4 suppresses lateral dispersal and cell penetration of collagen gels. In contrast, use of a broad-spectrum matrix metalloproteinase (MMP) inhibitor (GM6001) to block endogenous membrane type 1 matrix metalloproteinase (MT1-MMP) activity does not fully inhibit cell invasion. Using intact tissue explants, Ncad+ MCAs were also shown to efficiently rupture peritoneal mesothelial cells, exposing the submesothelial collagen matrix. Acquisition of Ncad by Ecad+ cells increased mesothelial clearance activity but was not sufficient to induce matrix invasion. Furthermore, co-culture of Ncad+ with Ecad+ cells did not promote a 'leader-follower' mode of collective cell invasion, demonstrating that matrix remodeling and creation of invasive micro-tracks are not sufficient for cell penetration of collagen matrices in the absence of Ncad. Collectively, our data emphasize the role of Ncad in intraperitoneal seeding of EOC and provide the rationale for future studies targeting Ncad in preclinical models of EOC metastasis.

Teaching approaches in South African dental schools: direct restorative procedures.

INTRODUCTION: Worldwide the use of amalgam has declined and mercury-containing products are banned in several countries. National and international opinions on amalgam were recently discussed in journals. According to surveys, significant time is spent on the teaching of amalgam in American, Canadian, Irish and United Kingdom Dental Schools. AIMS AND OBJECTIVES: To i) investigate the teaching approaches on direct restorative techniques and materials in South African Dental Schools; ii) compare the teaching approaches of the dental schools in South Africa with each other as well as with the American, Canadian, Irish and United Kingdom schools; iii) use the information of this study as baseline data for future studies on teaching approaches. METHODS: A questionnaire regarding the teaching and training of direct restorations was e-mailed to the heads of Restorative Dentistry departments in four South African Dental Schools in 2007. RESULTS: Significant time is spent on teaching and training of amalgam as a restorative material. Teaching and training on direct restorations are very similar in all South African Dental Schools. CONCLUSION: Although there is a decline in the use of amalgam worldwide, significant time is spent on teaching of amalgam restorations in South African Dental Schools and this corresponds to the curriculums of American, Canadian, Ireland and United Kingdom Dental Schools.

Microleakage of different amalgams bonded with dual cure resin cements.

INTRODUCTION: To reduce microleakage in high-copper amalgam restorations, bonding of amalgam was introduced. AIM: This study compared the microleakage of admixed and spherical amalgams when bonded with different bonding intermediates under thermo- and non-thermocycling conditions. METHOD AND MATERIALS: Class II butt-joint cavities were prepared in 200 extracted human molar teeth, and randomly divided into 5 groups. Calibra, Duo Cement Plus, RelyX ARC and Amalgambond Plus were applied to 4 of these groups. The fifth group was left untreated. The groups were further divided and restored with either Dispersalloy or Oralloy Magicap S. Ten specimens of each group were thermocycled between 5 degrees C and 55 degrees C, placed in basic fuchsin for 8 hours, sectioned and evaluated for dye penetration under 40X magnification. The mean microleakage scores were analysed using the chi-squared test at a confidence level of 95%. RESULTS: Microleakage of the non-bonded amalgams was significantly higher (p < 0.0001) than for the bonded amalgams (thermocycled and non-thermocycled). The microleakage of the different intermediates bonded to Dispersalloy (thermocycled and non-thermocycled) was not significantly different (p > 0.05). The microleakage of the different intermediates was not significant different except for Duo Cement compared to Calibra (p < 0.0001), RelyX (p < 0.0001) and Amalgambond (p = 0.0433) and Amalgambond compared to Calibra (p = 0.0433) and RelyX (p = 0.0433). The microleakage of the bonded amalgams was not significantly increased by thermocycling (p > 0.05). The microleakage of the two amalgams when bonded with the same resin cements (thermocycled and non-thermocycled) was not significantly different except for Duo Cement (thermocycled) (p = 0.0051) and RelyX (non-thermocycled) (p = 0.0356). CONCLUSIONS: Bonding amalgam restorations to tooth structure in butt-joint cavities will reduce microleakage of both admixed and spherical amalgam restorations. Thermal stress does not affect the bond adversely.

Effect of woven glass fibre reinforcement on the flexural strength of composites.

To measure and compare the flexural strength of composites reinforced with fibres, four groups of specimens (N = 10) were prepared from the combinations: Filtek Flow/Filtek Z250 and Esthet-X flow/Esthet-X dental composite. One group from each combination was reinforced with woven glass fibre (everStick net) and all the specimens subjected to three-point bend flexural testing. The mean and standard deviations for each test group were calculated and compared using one-way analysis of variance (ANOVA) followed by pairwise Bonferroni T-tests at a preset alpha of p < 0.05. It was found that fibre reinforcement significantly (p < 0.001) increased the flexural strength of both types of composites. As the inclusion of only one layer of glass fibre net produced an increase of approximately 30% in the flexural strength of the composite samples, it can be speculated that multiple layers would increase it even more. The use of fibre-reinforcement to strengthen directly placed composite crowns and bridges will enable the clinician to provide a more cost effective service as well as aesthetic dentistry to more patients.

[Ambulatory treatment of hemorrhoids]. / Comment je traite.... Les hémorroïdes en ambulatoire.

DGHAL (Doppler Guided Hemorrhoid Arterial Ligation) represents a new approach to the treatment of internal hemorrhoids; it entails exact and selective ligation of the arteries supplying the piles (hemorrhoids). The intervention can be performed on ambulatory patients under local anaesthesia. An anoscope is used which incorporates a Doppler head. The superior hemorrhoidal arteries are identified under guidance of the arterial Doppler sound and ligated through a window located just above the Doppler head. The intervention lasts some 30 minutes. Local discomfort can ensue for a few days following surgery. At one month, the time required for the internal haemorrhoids to fade away, the patient is seen again; an external hemorrhoid or residual skintag can then be considered for treatment under local anaesthesia if needed. As of November 2001 until today, more than 350 patients have been treated, and we report here on 150 of them. Long term data (6 months to 2 years) have been collected which includes 85 to 90% patient satisfaction.

Size of two-body weakly bound objects: short versus long range potentials.

The variation of the size of two-body objects is investigated, as the separation energy approaches zero, with both long range potentials and short range potentials having a repulsive core. It is shown that long range potentials can also give rise to very extended systems. Except for the l = 0 state, the asymptotic laws differ according to the range of the potential. For short range potentials defined by two and three parameters, their sensitivity to the shape and length is studied. These ideas as well as the transition from the short to the long range regime for the l = 0 case are illustrated using the Kratzer potential.

[Long-term results in ileo-anal reservoirs in the treatment of ulcero-hemorrhagic rectocolitis]. / Résultats à long terme du réservoir iléo-anal dans le traitement de la rectocolite ulcéro-hémorragique.

The authors report long term results of 53 ileo-anal anastomosis for ulcerative colitis. They used a "J" pouch technique with anastomosis to the anal canal after mucosectomy of the lower rectum. An upstream ileostomy should be created and left in place for two to three months. Early morbidity primarily involves pelvic or parietal infectious problems, while late complications comprise pelvic fistulae, obstructive events, and episodes of pouch inflammation. Functional results improve over the first year and remain stable thereafter. The major long term problem remains that of pouch inflammation its treatment, and the understanding of its pathophysiology.

Laparoscopic highly selective vagotomy.

Between February 1991 and August 1992, 35 patients underwent laparoscopic highly selective vagotomy (HSV) for recurrent duodenal ulcer disease. An antireflux procedure was also performed in 25 of these patients. There was no 30-day mortality and morbidity. The mean operating time was 110 (range 85-205) min for HSV and 155 (range 100-300) min for vagotomy and antireflux repair. Follow-up is short but initial postoperative gastric acid secretion studies have demonstrated results similar to those obtained after conventional open HSV. The main advantage of laparoscopic HSV is the reduction of 70 per cent in hospital stay and 50 per cent in the overall recovery period compared with open surgery.

Colpocystodefecography.

PURPOSE: To assess, in one single procedure, a complete study of the female pelvis, including the Douglas pouch. METHODS: Colpocystodefecography (CCD) combines vaginal opacification, voiding cystography, and defecography. Three hundred examinations are reviewed. RESULTS: Thanks to the simultaneous visualization of the pelvic structures, CCD proved to be more useful than clinical evaluation to diagnose prolapses and particularly Douglas pouch hernias (enteroceles), the clinical diagnosis of which was missed in 93 of 111 cases. Moreover, in addition to morphologic and functional information, CCD brings about a new insight in the study of pelvic organs reciprocal influences, should they be positive (supporting function) or negative (external compression). Finally, significative pelvic surgery and particularly hysterectomy enhances greatly the risk of enteroceles. CONCLUSION: CCD is helpful in the preoperative staging, especially in the selection of the surgical procedure that will least likely predispose to possible late postoperative complications such as vaginal prolapses or enteroceles.

Laparoscopic Nissen fundoplication: detailed analysis of 132 patients.

With the world-wide use of laparoscopy, new applications have been found, particularly in the field of esophageal and gastric surgery. From January 1991 through April 1992, 132 patients underwent laparoscopic Nissen fundoplication. The indication for laparoscopic intervention was symptomatic gastroesophageal reflux disease (GERD) not responding to medical treatment. The preoperative assessment included esophagogastroscopy, barium meal, esophageal manometry, and, in selected cases, 24 h pH studies. There was no operative-related mortality. The overall morbidity was 7.5%. Ninety-eight patients were seen 3 months after surgery and evaluated for control of reflux symptoms. One patient complained of mild recurrence of reflux symptoms; however, endoscopic examination revealed no evidence of recurrent esophagitis. Three complained of occasional dysphagia and two, of mild dysphagia. One individual required reoperation for persistent, severe dysphagia. The excellent results observed so far with this procedure have led us to believe that laparoscopic Nissen fundoplication is the procedure of choice for patients with intractable GERD.

Percutaneous catheter drainage of abdominal abscess after abdominal surgery. Results in 121 cases.

One hundred and twenty-one peritoneal, retroperitoneal and pelvic abscesses were treated percutaneously using CT or US guidance. The lesions developed after abdominal surgery. Sixty-three abscesses (52%) were situated in the peritoneal cavity, 31 (26%) in the retroperitoneal cavity and 27 (22%) in the pelvis. A definitive treatment was obtained in 74% of peritoneal abscesses, 67% of retroperitoneal abscesses and 82% of pelvic abscesses. Failure most commonly occurred with multiloculated lesions or lesions associated with fistulous communication. There was a low rate of complication (1%). percutaneous drainage avoids the risks inherent in surgery and anesthesia, saves considerable time and meets greater patient acceptance. If a total cure is not systematic, a beneficial temporizing effect may however be obtained by percutaneous drainage. This procedure should be indicated for the initial treatment of postsurgical abscesses.

[Tolerance of adjuvant treatment combining postoperative intraportal chemotherapy and a systemic treatment based on 5-fluorouracil in colorectal carcinoma with a histologically poor prognosis]. / Tolérance d'un traitement adjuvant associant une chimiothérapie intraportale post-opératoire et un traitement systémique à base de 5-Fluorouracil dans les carcinomes colorectaux de stades histopronostiques défavorables.

From April 89 to October 90, 41 patients operated for a Dukes B or C colorectal cancer were randomized to receive 6 courses of adjuvant treatment with (A) 5-FU alone (440 mg/m2 IV bolus 5/21 days) or (B) folinic acid (200 mg/m2 IV bolus 5/21 days) preceding 5-FU (370 mg/m2 in short infusion 5/21 days). Ten patients received also one course of immediate post-operative continuous portal infusion (5-FU 500 mg/m2/day x 7 followed by a 2 hours infusion of mitomycin C 10 mg/m2). The portal treatment was well tolerated (1 case of GI tract disturbances, 1 catheter obstruction). The toxicity of adjuvant systemic treatment was evaluated on 232 courses (125 A, 107 B). Hematologic and skin toxicities, alopecia and nausea-vomiting were mild. The limiting toxicities (expressed as percentages of courses) were stomatitis (grades 2-3: 11.4% A; 22.6% B) and diarrhea (grades 3-4: 7.3% A; 14.2% B; one toxic death was to deplore in arm B from a grade 4 diarrhea). The pilot study has demonstrated the feasibility of the adjuvant treatment proposed; a multicentric randomized trial (expected accrual: 800 patients) has therefore been activated on 11.01.90; all patients will also receive levamisole while radio-therapy will be mandatory for rectal cancer.

[Cholecystectomy using celioscopy: analysis of 368 operations]. / La cholécystectomie sous coelioscopie: analyse de 368 interventions.

The management of calculous disease of the biliary tract has undergone significant changes during the past decade. Yet, the only radical method of treatment remains cholecystectomy. The surgical option has been improved by the development of laparoscopic cholecystectomy. From February 1990 to February 1991, we performed 368 laparoscopic cholecystectomies, with no mortality and a morbidity rate of 3.8%. There were 283 women and 85 men, with a mean age of 56.2 years (range 18 to 92 years). Two patients were asymptomatic but presented with a growing gallbladder polyp. All the other patients were symptomatic: biliary colic (63.8%), dyspepsia (18.6%), or acute cholecystitis (17.6%); 36 patients had an history of stone migration to the main biliary tract. Mean operating time was 58.3 minutes (22 to 180 minutes) and mean postoperative stay was 3.4 days. There were four systemic complications and 10 local technically related complications: two have been controlled by a laparoscopic approach (one hemorrhage and one biliary leak), one by laparotomy (bile duct injury). The other 7 local complications resolved spontaneously (4 biliary fistulas) or by percutaneous punction (3 subphrenic abscesses). Twenty-six patients (7%) required conversion to open cholecystectomy because of technical difficulties with the dissection or main biliary tract stones. We conclude that laparoscopic cholecystectomy is a safe and effective procedure.

Laparoscopic Nissen fundoplication: preliminary report.

Twelve patients presenting with symptomatic esophagitis associated with hiatal hernia and gastroesophageal reflux underwent operative management under laparoscopic guidance. The antireflux procedure employed was the Nissen fundoplication. The authors completed the operation laparoscopically in nine patients. Postoperatively, patients were evaluated with repeat fiberoptic endoscopy, esophageal manometry, and barium contrast studies. Postoperative results were considered excellent on the basis of these studies and complete control of symptoms. The mortality rate was 0%. The only major operative complication was a pneumonia that occurred in one patient. At 1 month follow-up, six patients were totally asymptomatic. The authors conclude that laparoscopic treatment of gastroesophageal reflux associated with a hiatal hernia is feasible by a procedure that has already proven its value during open surgery.

[Defecation disorders. Characteristics of manometric studies and rehabilitation]. / Troubles de la défécation. Quelques particularités des épreuves manométriques et de la rééducation.

The authors review the literature and their personal experience about the systematic exploration of defecation disorders by anorectal manometry and colpocystodefecography. They stress the importance of combining functional and morphological evaluation, in order to avoid inappropriate surgery. Concerning anorectal manometry, the determination of the smallest volume of rectal distention inducing a complete relaxation of the internal anal sphincter was found more useful than the maximal tolerable volume in the exploration of defecation disorders. Finally, the authors report the results of biofeedback conditioning prescribed in 30 patients (27 women, 3 men, mean age: 55 years) with defecation disorders (terminal constipation in 21, fecal incontinence in 9 patients). Several characteristics of anorectal manometry and of defecography were significantly improved after biofeedback conditioning.