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Esterification of acetic, propanoic and pentanoic acid with methanol, ethanol, 1-propanol, 2-propanol, butanol and 2-butanol was studied in the presence of a fibrous polymer-supported sulphonic acid catalyst, Smopex-101. The reaction temperature in the experiments was 60 °C. Comparative experiments were carried out on an ion-exchange resin, Amberlyst 15 and with a homogeneous catalyst, liquid HCl. The effect of different molar ratios between the reactants (acid and alcohol) on the reaction rate was investigated. The rate constants were related to the substituent effects of the reacting molecules according to the Taft equation. The substituent effects of alcohols were found to follow the Taft relationship, which was not the case for the acids. The experimental results were modelled according to a simple second-order model and a more advanced adsorption-based model. The adsorption-based model, which includes the adsorption of carboxylic acid and water and is consistent with structure-activity relationship, was superior to the second-order model.

In CF surgery blockage of the nasolacrimal system is sometimes found. Most commonly this is seen in facial clefts and post-traumatic conditions. In this paper an anatomical classification is outlined, which divides the lacrimal passage system into 4 separate parts, each requiring special consideration in the planning of surgical correction. A new technique of transposing the upper punctum and canaliculus into the lower eyelid is also described. This can be used where the lower punctum has been damaged and the upper punctum is intact, but is unable to prevent epiphora.

Four patients with Xeroderma pigmentosum are reported: 2 diagnosed following the development of multiple cutaneous tumours, and 2 at an earlier state. The repair synthesis of DNA after ultraviolet radiation was reduced in 3 and normal in 1 patient. Para-aminobenzoic acid (PABA) was used topically as sunscreen; for those intolerant to PABA, alternatives are given. 5-fluoro-uracil had satisfactory effect against actinic keratoses. Two patients had associated neurologic and mental abnormalities compatible with deSanctis-Cacchione syndrome, a Xeroderma pigmentosum variant.

The oblique sliding osteotomy has been used for surgical correction of mandibular prognathism, sometimes in combination with open bite, in 112 patients treated from 1969 to 1978. The method has proved to be connected with few surgical complications and minimal relapse tendency. No correlation was found between the degree of posterior positioning or closure of open bite at the operation and relapse tendency. Consequently no limitations in the field of application concerning the degree of mandibular protrusion or open bite have been found in this study.

This long-term study was a follow-up of 46 patients with complete unilateral cleft lip and palate treated with secondary or late secondary bone grafting. Surgeons with different degrees of experience in this procedure had operated on these patients. Morphology of the clefts prior to the grafting was assessed with regard to width of cleft, stage of eruption of permanent canine, presence or absence of permanent lateral incisor and position of permanent lateral incisor and permanent canine in the dental arch. Outcome of surgery was evaluated with regard to the amount of bleeding, flap dehiscence, alveolar bone height, and space closure in the previous cleft area. Dehiscence rate was 23% (11) and total failure rate was 4% (2). Alveolar bony height in 38 patients (81%) was more than 75% of the normal alveolar bone height; in 6 cases (13%) between 50-75% bone height and in 3 subjects (6%) surgery had given less than 50% of the normal bone height. Cleft space was closed by orthodontic means in 49% of patients. Best results were obtained when bone grafting was performed prior to canine eruption. Furthermore, significantly better results regarding alveolar bone height were obtained by the more experienced surgeons.

One hundred and sixty-five patients with localized cancer of the lower lip were excised and reconstructed over a 25-year period using Bengt Johanson's step technique. Eighty-eight percent of the tumors were less than 2 cm in size and 65% were of high histopathological differentiation. Fifty-six percent were reconstructed with bilateral step flaps. Nine local recurrences appeared in 5 patients, none of whom died of lip cancer. Eight patients later developed regional metastases and 3 of these patients died of lip cancer. The 5-year survival rate was 98%. The step technique is recommended for reconstruction of lip defects of up to 2/3 of the lower lip and may, in larger resections, be combined with either a fan flap or an Estlander flap. The outstanding functional results are due to the use of adjacent tissue for the reconstruction which preserves the normal arrangement of muscles, vessels and nerves.

The right ear of mice was scalded at 51 °C and 53 °C for 20 s, using the recently developed dip burn model, and examined morphologically and histochemically at intervals for 2 h postburn. The left, unburned ear served as control. Burned ears intended for light and electron microscopy were fixed in situ by means of vascular perfusion. Ears for histochemical studies were cut off and immediately frozen at -140 °C. The enzyme histochemical analyses comprised a variety of oxido-reductases and hydrolases. After a 51 °C scald, scattered epidermal cell damage was observed with intracellular edema and mitochondrial destruction. Most microvessels were patent. Scalding with 53 °C water produced extensive cellular changes in the epidermis from 5 min including mitochondrial alterations, tonofilament aggregation and intercellular separations, progressing into complete epidermal destruction and lysis at 2 h postburn. Morphologically, many microvessels were occluded by cellular aggregates or debris after endothelial cell destruction. Of the histochemical assays the test for succinic dehydrogenase gave conclusive results that correlated well with the morphological findings, indicating partial dysfunction of epidermal cells 2 h postburn after a 51 °C scald and early, almost total absence of activity from 5 min postburn after a 53 °C scald injury. Scalding at 53 °C invariably leads to ear necrosis. This might be explained by the epidermal destruction, which in turn seems related to mitochondrial viability, and microcirculatory blood flow. The sensitivity of this experimental model precludes direct comparisons with studies of scalds to skin covering large tissue volumes.

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