Robotic-assisted mesh pelvic closure for prevention of small bowel descent after surgery for recurrent rectal cancer

Techniques in Coloproctology -     

Anal endosonography for recurrent anal fistulas: Image enhancement with hydrogen peroxide

Anal endosonography is a new technique that is useful in the preoperative assessment of patients with anal fistulas. Endosonographic images are created by the reflection of sound waves from the interfaces between tissues of varying densities. In order to accentuate tissue interface layers at the level of the fistula tract, we introduced hydrogen peroxide into the fistula tract through the external opening during anal ultrasonography in two patients with recurrent anal fistula. Hydrogen peroxide injection resulted in hyperechoic imaging of the preinjection hypoechoic horseshoe fistula tract. Endosonographic findings were confirmed at the time of surgery in both patients. We conclude that hydrogen peroxide enhancement of the fistula tract is a simple, effective, and safe method of improving the accuracy of endoanal ultrasound assessment of recurrent anal fistula.Dr. Cheong is a visiting clinician from the Department of Surgery, Tan Tock Seng Hospital, Moulmein Road, Singapore 1130.     

Combined effects of radiotherapy and angiostatin gene therapy in glioma tumor model

The objective of the present study was to evaluate the antitumor effect of a defective adenovirus expressing a secretable angiostatin-like molecule (AdK3) in combination with radiotherapy in rat C6 gliomas s.c. preestablished into athymic mice. In vitro, the combination regimen was significantly (P < 0.001) more cytotoxic for human microcapillary endothelial cells than either treatment alone, whereas survival of C6 glioma cells was not affected in the conditions used. Radiotherapy and AdK3 gene delivery was then studied on well established C6 xenografts (165 +/- 70 mm(3)). In these tumors, AdK3 intratumoral injections had only a marginal effect. Interestingly, when experimental radiotherapy was added, significantly higher (P < 0.005), and possibly synergistic, antitumoral effects were observed that tightly correlated a marked decrease of intratumoral vascularization. The combination of radiotherapy and AdK3 intratumoral injections also revealed a significant (P < 0.05) inhibition of tumor growth as compared with either treatment alone for larger tumors (467 +/- 120 mm(3)). Altogether, these data emphasize the potential of combining a destructive strategy directed against the tumor cells with an anti-angiogenic approach to fight cancer.     

COMPLEMENTARY FRACTIONS OF DENATURED DNA OF COLIPHAGE T3 AS TEMPLATES FOR TRANSCRIPTION

This paper discusses the evidence that two fractions obtained by the chromatography of denatured DNA of phage T3 on columns of methylated albumin-kieselguhr represent the complementary strands. This evidence derives from a variety of temperature-absorbance measurements and from the base composition of the RNA products synthesized by RNA polymerase under the direction of the two single-stranded DNA templates.     

Configuration Interaction in the Calculation of Oscillatory and Rotatory Intensities of Nonplanar pi-Electronic Systems

The interaction of configurations, including all possible singly excited configurations, is incorporated into the calculation of oscillatory and rotatory intensities of simple nonplanar π-electronic systems such as skewed butadiene and acrolein. The results are discussed in terms of the reliability of the (self-consistent field)-(linear combination of atomic orbitals)-(molecular orbital) wave functions employed.