Recurrence after surgical treatment of hidradenitis suppurativa.

From six to 89 months after surgery 82 patients who had been treated by radical surgery (118 excisions) for intractable hidradenitis suppurativa were reviewed. Local recurrence rates varied greatly with the disease site, being low after axillary (3%) and perianal surgery (0%) and high after inguinoperineal (37%) and submammary (50%) excision. Recurrence results from inadequate excision or an unusually wide distribution of apocrine glands, but physical factors such as obesity, local pressure, and skin maceration played a part in a few patients. Recurrence due to inadequate surgery tended to be the most troublesome. At follow up 75 (91%) of the patients were pleased with the results of their operation. A quarter of the patients developed disease at a new anatomical site after operation. Radical surgery gives good symptomatic control of severe hidradenitis suppurativa of the axilla, inguinoperineal, and perianal regions but is less satisfactory for submammary disease.     

The thoracodorsal artery perforator flap in the treatment of axillary hidradenitis suppurativa: effect on preservation of arm abduction

Hidradenitis suppurativa is a chronic, recurrent inflammatory disease of the skin characterized by abscesses and scars. The axillary region is predominantly affected, leading to limited mobility of the arm due to scar retraction. This prospective study aimed to analyze the surgical treatment of severe lesions of axillary hidradenitis suppurativa by using the thoracodorsal artery perforator flap while focusing on the preservation of arm abduction. We enrolled 12 patients with severe axillary hidradenitis suppurativa who underwent bilateral surgical treatment of their lesions by radical excision, followed by immediate reconstruction with the thoracodorsal artery perforator flap. The amplitude of arm abduction was measured preoperatively and 6 months postoperatively by goniometry, and statistical analysis was performed using Student's t test. Preoperative and 6-month postoperative mean amplitude of arm abduction were 98.7 degrees and 152.7 degrees, respectively, with a significant mean increase of 54 degrees (p<0.0001). The thoracodorsal artery perforator flap can be used as a good option for axillary reconstruction after radical excision of severe lesions of hidradenitis suppurativa, and its use would allow a significant increase in the amplitude of arm abduction. It has several other advantages when compared with other types of coverage, including its anatomical proximity to the axilla, similar thickness, and high-quality skin. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.     

The use of Ultroser G as a serum substitute in the culture of human skin fibroblasts

Growth of human skin fibroblasts was dramatically enhanced when serum in the culture medium was replaced by Ultroser G. Compared to the same cells cultured in the presence of serum, alterations in glucose and lipid metabolism and an increase in the activity of prolidase (EC 3.4.13.9) and prolinase (EC 3.4.13.8) were also observed. Consequently, we advise extreme caution in the use of Ultroser G in metabolic studies, especially for periods of culture exceeding 10 days. However, Ultroser G can help to produce a large number of cells and so facilitate purification of the proteins produced during the stationary growth phase.     

The rhomboid-to-W technique for excision of some skin lesions and closure.

A method is descirbed whereby a skin lesion is excised as a rhomboid, and adjacent flaps are then created and transposed to close the defect in a W. A. pleasing scar line results, one which is easily hidden in the natural creases.     

The use of genome-level characters for phylogenetic reconstruction

Now that large-scale genome-sequencing projects are sampling many organismal lineages, it is becoming possible to compare large data sets of not only DNA and protein sequences, but also genome-level features, such as gene arrangements and the positions of mobile genetic elements. Although it is unlikely that comparisons of such features will address a large number of evolutionary branch points across the broad tree of life owing to the infeasibility of such sampling, they have great potential for resolving many crucial, contested relationships for which no other data seem promising. Here, I discuss the advancements, advantages, methods, and problems of the use of genome-level characters for reconstructing evolutionary relationships.     

The nature of X-ray-induced mutations after recovery in excision repair-deficient (mus-201) Drosophila females

This paper describes the genetic analysis of X-ray-induced mutations at several visible loci (yellow, white, Notch, vermilion and forked) located on the X-chromosome of Drosophila melanogaster after recovery in excision repair-deficient condition (mus-201). A total of 118 mutations observed in 83636 F1 females were analyzed. The white mutations in particular have been investigated at the molecular level. The results show that: (1) the frequency of recovered whole-body mutations is similar or slightly lower in repair-deficient than in repair-proficient condition (respectively 1.5 x 10(-4)/locus/15 Gy and 2.3 x 10(-4)/locus/15 Gy); (2) the frequency of observed mosaic mutations is significantly higher in the repair-deficient condition than in the proficient condition (respectively 2.7 x 10(-4)/locus/15 Gy and 0.9 x 10(-4)/locus/15 Gy); (3) the analysis of F2 male lethal mutations and the cytological analysis of the recovered mutations in the excision repair-deficient condition indicate a decrease in mutations associated with gross chromosomal aberrations (including multilocus deletions); (4) at the molecular level, the spectrum of recovered intragenic mutations is similar after excision-deficient and -proficient repair. These results indicate that excision repair is involved in X-ray-induced DNA damage that is repaired efficiently in the normal repair condition, but bypassed in the excision repair-deficient condition, leading to mosaic mutations. In addition, lesions that apparently cannot be bypassed by DNA replication lead to a decrease in the fraction of mutations due to gross chromosomal aberrations among the whole-body mutations.     

The role of trehalose as a substitute for nitrogen-containing compatible solutes (Ectothiorhodospira halochloris)

The halophilic phototrophic bacterium Ectothiorhodospira halochloris is able to synthesize both nitrogen-containing (betaine, ectoine) and nitrogen-free (trehalose) compatible solutes. In the absence of external ammonium and under nitrogen-limited growth conditions ectoine was metabolized and trehalose partly replaced betaine. The cytoplasmic trehalose concentration did not exceeded 0.5 mol/kg water (approx. 30% of total compatible solutes). A decreasing content of betaine in cells growing under nitrogen limitation is a result of decreased biosynthesis. Apparently, the betaine pool cannot be used as a nitrogen source, not even in a situation of total nitrogen depletion.     

Ethylene evolution from various developing organs of olive (Olea europaea) after excision

Ethylene evolution from leaves, stems, inflorescences and fruits of the olive plant ( Olea europaea L.) cv. Manzanillo was studied at various stages of their development. Mature non-growing organs, particularly leaves, have a constant, low, and uniform rate of ethylene evolution. Ethylene evolution from detached mature olive leaves was constant during the first 12 h after excision. Leaves on shoots maintained in vitro kept a constant rate of ethylene evolution for at least the first 5–6 days. Leaf injury significantly increased ethylene evolution. Ethylene evolution from injured and non-injured control leaves could be markedly inhibited aminoethoxyvinylglycine (AVG) applied to the leaves or fed to the shoot. The use of excised olive shoots and leaves as an in vitro model system for studies of induced metabolic processes such as abscission and developing water stress was suggested.     

The cobalamin (coenzyme B12) biosynthetic genes of Escherichia coli.

The enteric bacterium Escherichia coli synthesizes cobalamin (coenzyme B12) only when provided with the complex intermediate cobinamide. Three cobalamin biosynthetic genes have been cloned from Escherichia coli K-12, and their nucleotide sequences have been determined. The three genes form an operon (cob) under the control of several promoters and are induced by cobinamide, a precursor of cobalamin. The cob operon of E. coli comprises the cobU gene, encoding the bifunctional cobinamide kinase-guanylyltransferase; the cobS gene, encoding cobalamin synthetase; and the cobT gene, encoding dimethylbenzimidazole phosphoribosyltransferase. The physiological roles of these sequences were verified by the isolation of Tn10 insertion mutations in the cobS and cobT genes. All genes were named after their Salmonella typhimurium homologs and are located at the corresponding positions on the E. coli genetic map. Although the nucleotide sequences of the Salmonella cob genes and the E. coli cob genes are homologous, they are too divergent to have been derived from an operon present in their most recent common ancestor. On the basis of comparisons of G+C content, codon usage bias, dinucleotide frequencies, and patterns of synonymous and nonsynonymous substitutions, we conclude that the cob operon was introduced into the Salmonella genome from an exogenous source. The cob operon of E. coli may be related to cobalamin synthetic genes now found among non-Salmonella enteric bacteria.