Outcome analysis of the transglabellar/subcranial approach for lesions of the anterior cranial fossa: A comparison with the classic craniotomy approach

The classic approach to anterior skull base lesions uses bifrontal craniotomies together with lateral rhinotomies. This approach requires frontal lobe retraction and is associated with postoperative anosmia and the development of frontal lobe encephalomalacia. The transglabellar/subcranial approach permits removal of anterior skull base lesions without frontal lobe retraction and avoids facial scars. No studies to date, however, have directly compared the two approaches in terms of patient morbidity. The present retrospective study compares the two approaches when used for the removal of anterior skull base lesions in terms of estimated blood loss, number of transfusions, number of days in the hospital and intensive care unit, and postoperative complications. Twenty patients with anterior skull base lesions were examined. The classic approach was used on 10, and the transglabellar/subcranial route was used on 10. When compared with the classic approach, the transglabellar/subcranial approach resulted in a lower estimated blood loss and subsequent transfusion rate, fewer days in the hospital and intensive care unit, and lower numbers and less severe types of complications. Furthermore, visualization of the tumors before resection with the transglabellar/subcranial approach allowed preservation of olfaction in virtually all of these patients. Although this study represents a small sample population, the results are sufficiently impressive to favor the transglabellar/subcranial approach for the removal of a variety of anterior skull base lesions. (Otolaryngol Head Neck Surg 1997;116:642-6.)     

A novel approach to improve undergraduate surgical teaching

Background:

Undergraduate surgery is at an important crossroads. Many departments report significant difficulties delivering effective teaching. Our student feedback indicated a dated surgical curriculum lacking structure, quality and uniformity. We report on a new ”blended” approach employing a combination of professional DVDs, case based discussions, online material and traditional bedside teaching designed to provide structure, standardization, and equality of learning .

Methods:

Year 4 students who had undertaken the new course and year 5 students who had participated in the traditional teaching programme were compared. Students completed a 20 item questionnaire about their experiences of the surgical teaching programme.

Results:

One hundred and seventy-one year 4 (70%) and148 year 5 students (66%) responded. Domains relating to “Overall Satisfaction with the course”, “Approval of innovative teaching methods and interactivity” and “Satisfaction with the clarity of course information” showed improvements when comparing the new and old programmes. However bedside teaching was not rated as highly in the new programme (p<0.05).

Conclusion:

This blended approach has resulted in improved student understanding and engagement. The apparent compromise of bedside teaching may be a reflection of higher expectations. We believe that a similar blended approach has the potential to re-invigorate surgical teaching elsewhere.     

Solid state and solution conformation of Boc-L-Met-Aib-L-Phe-OMe

The conformation of the peptide Boc-L-Met-Aib-L-Phe-OMe has been studied in the solid state and solution by X-ray diffraction and ¹H n.m.r., respectively. The peptide differs only in the N-terminal protecting group from the biologically active chemotactic peptide analog formyl-L-Met-Aib-L-Phe-OMe. The molecules adopt a type-II ß-turn in the solid state with Met and Aib as the corner residues (øMet =- 51.8^o, øMet = 139.5^o, øAib = 58.1^o, øAib = 37.0^o). A single, weak 4 -> 1 intramolecular hydrogen bond is observed between the Boc CO and Phe NH groups (N—O 3.25 Å, N-H—O 128.4^o). ¹Hn.m.r. studies, using solvent and temperature dependencies of NH chemical shifts and paramagneti radical induced line broadening of NH resonances, suggest that the Phe NH is solvent shielded in CDCI₃ and (CD₃)₂SO. Nuclear Overhauser effects observed between Met Cα H and Aib NH protons provide evidence of the occurrence of Met-Aib type-II ß-turns in these solvents.     

Synthesis and characterization of defensin NP-1

Defensins are a group of small, cationic, antimicrobial proteins found in the cytoplasmic granules of neutrophils and macrophages of a variety of mammalian species. One such defensin, NP-1, isolated from rabbit neutrophils, has been shown to consist of 33 amino acids rich in arginine and cysteine residues (6). We have synthesized NP-1 on an Applied Biosystems Model 431A peptide synthesizer using FastMoc? chemistry involving HBtu [2-1H-benzotriazol-1-y1)-1,1,3,3-tetramethyluronium hexafluorophosphate] activation for coupling amino acids. The linear peptide was folded by air oxidation to the biologically active form containing three disulfide bonds and purified by reverse phase chromatography. The amino acid sequence of the synthetic peptide was confirmed by Edman degradation. Molecular weight determination by plasma desorption mass spectroscopy (PDMS) gave a value of 3898.6, in agreement with the expected molecular weight of 3898. The biological activity of the synthetic peptide, as measured by its antifungal activity against several pathogenic fungi, was indistinguishable from that of the natural NP-1. Also, the CD spectrum was equivalent to that of natural NP-1, indicating conformational identity of the two species.     

Low-dose recombinant interferon therapy in anti-HBe-positive chronic hepatitis B in Asian Indians*

Approximately 15% of Indian patients with hepatitis B virus (HBV)-related chronic liver disease (CLD) have infection with precore mutant forms. These patients are likely to have an aggressive course. There are equivocal reports of success with interferon therapy of mutant infection in the West. This therapy has not been evaluated in precore mutant-related CLD in Asian Indians. Eighteen patients (mean age 38.2 ± 12 years, M: F: 17: 1) with biopsy proven CLD and precore mutant HBV infection (hepatitis B surface antigen (HBsAg) positive, hepatitis B e antigen (HBeAg) negative, anti-HBe positive, HBV-DNA positive) were included. Interferon alpha 2b was given at 3 mIU on alternate days for 4 months. Serology, determination of HBV-DNA (both by dot-blot hybridization and polymerase chain reaction) and liver biopsy were repeated after completion of the therapy. Response to interferon therapy was defined as loss of HBV-DNA by dot-blot hybridization. Thirteen (72.2%) patients responded to the treatment (responders). Mean alanine aminotransferase levels (83 ± 12 vs 55 ± 29 IU/L, P < 0.01) and the histological activity index (15 ± 1.4 vs 12 ± 1.3, P < 0.01) significantly decreased in the responders compared with initial values. Serum albumin levels also improved at the end of the therapy (3.5 ± 0.4 g/dL vs 3.8 ± 0.4 g/dL, P= 0.07). During follow up, seven of the 13 (54%) responders relapsed; cirrhotics relapsed more often than chronic hepatitis patients (P < 0.05). All 18 patients, however, continued to be HBV-DNA positive at the end of follow up. This study concluded that: 1. Interferon therapy is beneficial, albeit to a limited extent, in HBV precore mutant-related chronic liver disease in Asian Indians. 2. It is ineffective in eliminating the mutant HBV infection, which explains the high relapse rate. 3. Prolonged low-dose interferon therapy alone or in combination with newer nucleoside analogues should be evaluated in these patients.     

Coexisting Hereditary Methaemoglobinaemia and Heterozygous β-Tialassaemia

ABSTRACT. Cyanosis was noted within a few weeks after birth in two sisters. On investigation the cause of cyanosis was found to be congenital methaemoglobinaemia due to NADH diaphorase deficiency. Heterozygous β-thaiassaemia was present as an additional incidental finding in one of the sisters, but did not contribute to the symptoms, thus showing that the two diseases, when coexistent, do not pose additional haematological problems. However, it is possible that the β-thalassaemia counteracts the tendency to compensatory erythrocytosis induced by methaemoglobinaemia     

Microcomputer simulations as aids in medical education: application in clinical chemistry†

A microcomputer-based learning program based on a dynamic simulation model has been developed for clinical chemistry. It allows a student to interrogate, examine, prescribe therapy and request laboratory tests on a simulated patient. The patient's condition changes with time and in response to the student's actions and thus the student experiences the simulated consequences of any action.