Positive compared with negative margins in a single-centre retrospective study on 3957 consecutive excisions of basal cell carcinomas. Associated risk factors and preferred surgical management.

The rate of margins involvement and the associated recurrence risk in basal cell carcinomas (BCCs) varies widely in published works (7%-25% and 26%-67%, respectively). This study investigated the risk factors associated with incomplete excision and their relevance in surgical management when positive margins occur in 3957 BCCs excised in 2358 patients. This study performed a multivariate analysis on the database collected from all patients operated for BCCs in the Plastic Surgery Department between 1 January 1992 and 1 September 2007. All data collected (3957 excisions; 2358 individuals) were divided into complete and incomplete excisions groups and analyzed according to 14 variables. The overall rate of incomplete excisions was 14%. Mean age (68), size of the lesion (< 0.5 cm), BCC subtype (nodular with sclerosant aspects, sclerosant and basosquamous), location (face), infiltration depth (hypodermis and deep tissues), recurrent BCC and re-excised BCC were significantly associated with a higher rate of incomplete excision. The recurrence rate for incompletely excised tumours was 26.8%, while only 5.9% for completely excised tumours. Most of the risk factors associated to incomplete excision can be identified before surgery (by simple anamnesis and clinical examination) and successfully overcome by appropriate surgical margins. The high recurrence rate after incomplete excision and the low patient compliance towards follow-up should lead the surgeon to early re-excise residual cancer.

Limb contouring after massive weight loss: functional rather than aesthetic improvement.

BACKGROUND: After massive weight loss, both upper and lower limbs show a similar deformity which consists of redundancy and ptosis of the cutaneous mantle. Many disturbances are associated with this abnormality, which can be treated surgically. A retrospective review of limb-contouring procedures after massive weight loss is presented. METHODS: Thigh lift and arm lift procedures are described. All surgeries of upper and lower limbs contouring performed between 2003 and 2006 are reviewed with regard to quantity of tissue removed, comorbidities, complications and patients' satisfaction, which was surveyed through a questionnaire exploring functional and esthetic results (maximum score 3). RESULTS: Among 48 bilateral limb-contouring procedures, medial thigh lifts were 35 (73%) and brachioplasties were 13 (27%). Mean age was 46 and average body mass index variation was 20 kg/m(2). The most frequent comorbidity was gallstones (28%). In 46% of the whole group of patients, there was no complication to mention. The most frequent complication was acute anaemia in both procedures (43% in thigh lift and 54% in arm lift). Mean quantity of adipose-dermoid tissue removed was 766 g in thigh lift and 463 g in arm lift. In case of surgery combined with liposuction, the average aspirated volume was 1,933 ml (thighs) and 1,117 ml (arms). Patients' satisfaction was 2.7 for thighs and 2.6 for arms, as average. CONCLUSION: The rate of complications in limb contouring after weight loss is higher than the analogue esthetic procedures. Nevertheless, due to the rehabilitative significance of limb surgery after weight loss, this step is to be included as fundamental in obese patients' surgical therapy.

Delayed treatment of persistent radial nerve paralysis associated with fractures of the middle third of humerus: review and evaluation of the long-term results of 52 cases.

This study was undertaken to determine the efficacy of delayed surgical treatment in cases of persistent radial nerve paralysis after fractures of the middle third of the humerus. We have limited this study to patients who had absolutely no functional recovery of the radial nerve 3 to 4 months after middle third humeral fractures. The fractures were treated by a variety of orthopaedic methods, conservative and surgical, in other departments and hospitals. Surgical exploration of the radial nerve was carried out 3 to 4 months after primary orthopaedic treatment. The outcome of this study concurs with data in the literature in showing that delayed nerve surgery (neurolysis or nerve grafts) in the absence of functional recovery of the radial nerve after humeral fracture can be useful in achieving good functional recovery and subjectively satisfying results.

Co-purification of mitochondrial HSP70 and mature protein disulfide isomerase with a functional rat kidney high-M(r) cysteine S-conjugate beta-lyase.

S-(1,1,2,2-Tetrafluoroethyl)-L-cysteine (TFEC, the cysteine S-conjugate of tetrafluoroethylene) is an example of a nephrotoxic, halogenated cysteine S-conjugate. Toxicity results in part from the cysteine S-conjugate beta-lyase(s)-catalyzed conversion of TFEC to a thioacylating fragment with the associated production of pyruvate and ammonia. In the present study, we have demonstrated that rat kidney homogenates contain at least three enzyme fractions that are capable of catalyzing a cysteine S-conjugate beta-lyase reaction with TFEC. One of these fractions contains a high-M(r) lyase. At least two proteins co-purify with this high-M(r) complex. N-Terminal analysis (15 cycles) revealed that the smaller species was mature protein disulfide isomerase (M(r) approximately 54,200) from which the 24 amino acid endoplasmic reticulum signal peptide had been removed. Internal amino acid sequencing (15 cycles) revealed that the larger species was mitochondrial HSP70 (mtHSP70; M(r) approximately 75,000). The present findings offer an explanation for the previous observation that mtHSP70 in kidney mitochondria is heavily thioacylated when rats are injected with TFEC (Bruschi et al., J Biol Chem 1993;268:23157-61).

Enhanced acetaminophen hepatotoxicity in transgenic mice overexpressing BCL-2.

Mitochondria play an important role in the cell death induced by many drugs, including hepatotoxicity from overdose of the popular analgesic, acetaminophen (APAP). To investigate mitochondrial alterations associated with APAP-induced hepatotoxicity, the subcellular distribution of proapoptotic BAX was determined. Based on the antiapoptotic characteristics of BCL-2, we further hypothesized that if a BAX component was evident then BCL-2 overexpression may be hepatoprotective. Mice, either with a human bcl-2 transgene (-/+) or wild-type mice (WT; -/-), were dosed with 500 or 600 mg/kg (i.p.) APAP or a nonhepatotoxic isomer, N-acetyl-m-aminophenol (AMAP). Immunoblot analyses indicated increased mitochondrial BAX-beta content very early after APAP or AMAP treatment. This was paralleled by disappearance of BAX-alpha from the cytosol of APAP treated animals and, to a lesser extent, with AMAP treatment. Early pathological evidence of APAP-induced zone 3 necrosis was seen in bcl-2 (-/+) mice, which progressed to massive panlobular necrosis with hemorrhage by 24 h. In contrast, WT mice dosed with APAP showed a more typical, and less severe, centrilobular necrosis. AMAP-treated bcl-2 (-/+) mice displayed only early microvesicular steatosis without progression to extensive necrosis. Decreased complex III activity, evident as early as 6 h after treatment, correlated well with plasma enzyme activities at 24 h (AST r(2) = 0.89, ALT r(2) = 0.87) thereby confirming a role for mitochondria in APAP-mediated hepatotoxicity. In conclusion, these data suggest for the first time that BAX may be an early determinant of APAP-mediated hepatotoxicity and that BCL-2 overexpression unexpectedly enhances APAP hepatotoxicity.

The distally based superficial sural flap: our experience in reconstructing the lower leg and foot.

The treatment of soft-tissue defects of the lower third of the leg and foot is often an awkward problem to tackle because of the frequent involvement of muscle, tendon, and bone, which is caused by the thinness and poor circulation of the skin covering them and by the small quantity of local tissue available for reconstruction. The authors present their experience with the use of sural flaps for the treatment of small- and medium-size defects of the distal region of the lower limb. The flap used was a distally based fasciocutaneous flap raised in the posterior region of the lower two thirds of the leg. Vascularization was ensured by the superficial sural artery, which accompanies the sural nerve together with the short saphenous vein. The authors treated 18 patients (12 men and 6 women) from May 1997 to August 1999 at the Division of Plastic Surgery, University of Turin, Italy. Superficial necrosis without involvement of the deep fascia (which was grafted 1 month later) occurred in 1 patient of the 18 treated. In another 2 patients, defects were found in the flap margins, but no additional surgical revision was necessary, and recovery occurred by secondary intention. In every patient the sural flaps provided good coverage of the defects, both from a functional and an aesthetic point of view. The major advantages of this flap are its easy and quick dissection. Because the major arterial axis is not sacrificed, this flap can be used in a traumatic leg with damaged major arteries.

Mitochondrial stress protein recognition of inactivated dehydrogenases during mammalian cell death.

The mammalian renal toxicant tetrafluoroethylcysteine (TFEC) is metabolized to a reactive intermediate that covalently modifies the lysine residues of a select group of mitochondrial proteins, forming difluorothioamidyl lysine protein adducts. Cellular damage is initiated by this process and cell death ensues. NH2-terminal sequence analysis of purified mitochondrial proteins containing difluorothioamidyl lysine adducts identified the lipoamide succinyltransferase and dihydrolipoamide dehydrogenase subunits of the alpha-ketoglutarate dehydrogenase complex (alphaKGDH), a key regulatory component of oxidative metabolism, as targets for TFEC action. Adduct formation resulted in marked inhibition of alphaKGDH enzymatic activity, whereas the related pyruvate dehydrogenase complex was unmodified by TFEC and its activity was not inhibited in vivo. Covalent modification of alphaKGDH subunits also resulted in interactions with mitochondrial chaperonin HSP60 in vivo and with HSP60 and mitochondrial HSP70 in vitro. These observations confirm the role of mammalian stress proteins in the recognition of abnormal proteins and provide supporting evidence for reactive metabolite-induced cell death by modification of critical protein targets.

[Cranioplasty with polymethylmethacrylate. The clinico-statistical considerations]. / Cranioplastica con polimetilmetacrilato. Considerazioni clinico-statistiche.

BACKGROUND: The main purpose of the reconstruction of the cranium is the protection of the brain. Besides we have to consider important functional and aesthetic necessities in order to achieve satisfactory results. METHODS: Thirty-six clinical cases, operated from November 1991 to June 1996, in which the reconstruction of the cranial vault is carried out by a polymethylmethacrylate acrylic resin are analysed. The causes and locations of the most common bone defects and the main indications for reconstruction are examined. While the repair of the osseous gaps caused by neoplasms is immediate, in the traumatic occurrences, in order to reduce the probability of infectious complications, an average time of 11 months elapsed from the first operation. The surgical technique, with slightest alterations, is the same in all the presented cases, preparing the acrylic resin straight on the operating table. The resin, moulded and adapted to the defect until its complete hardening, presents, thanks to its properties, manifold advantages (and few real disadvantages). RESULTS: The results, in terms of complications, are very satisfactory, with an infectious rate of 2.7%. Besides, in one third of the patients, a considerable clinical improvement after the repair has been observed. CONCLUSIONS: According to personal experience, it is possible to affirm that polymethylmethacrylate, with its remarkable plasticity and stability in time, can always guarantee a satisfactory functional and aesthetic result.

Mitochondrial stress protein actions during chemically induced renal proximal tubule cell death.

We have previously shown that the potent mammalian nephrotoxicant tetrafluoroethyl-L-cysteine (TFEC) covalently modifies a select group of mitochondrial proteins prior to cell death. More recently we have identified these adducted proteins as subunits of mitochondrial dehydrogenase multienzyme complexes, which are involved in key regulatory steps of cellular respiration. Most importantly the E2 and E3 subunits of alpha-ketoglutarate dehydrogenase are adducted. We report here that the consequence of adduction is the formation of tertiary complexes between dehydrogenase subunits and the mitochondrial heat shock protein 60 (HSP60) and a HSP70 homolog (mortalin/PBP74). Thus, adduction perturbs protein structural integrity sufficiently to allow for mitochondrial stress protein recognition. These data also suggest that, in our mammalian system, HSP60 appears to act in the identification and maintenance of protein integrity, as has been previously established for simpler eukaryotic systems.

Mitochondrial HSP60 (P1 protein) and a HSP70-like protein (mortalin) are major targets for modification during S-(1,1,2,2-tetrafluoroethyl)-L-cysteine-induced nephrotoxicity.

The potent and site-selective nephrotoxicity of S-(1,1,2,2-tetrafluoroethyl)-L-cysteine (TFEC) in vivo has been associated with difluorothioamidyl-L-lysine formation on critical mitochondrial target proteins. Dose-response studies in the Fischer 344 rat indicate that five proteins with apparent molecular masses of 99, 84, 66, 52, and 48 kDa are predominantly adducted in vivo after nephrotoxic doses of TFEC (> 10 mg/kg, intraperitoneally). Microsequence analysis of the major difluorothioamidyl-L-lysine proteins indicated that P66 is identical, over 14 NH2-terminal residues, to mitochondrial P1 protein (HSP60, a chaperonin) and that P84 is identical, over 14 residues, to a recently isolated novel member of the HSP70 family known as mortalin. These studies indicate that mitochondrial heat shock proteins are major targets for modification by reactive metabolites of TFEC. The implications of these data in relation to the nephrotoxicity of cysteine conjugates are discussed.

In vitro cytotoxicity of mono-, di-, and trichloroacetate and its modulation by hepatic peroxisome proliferation.

Dichloroacetate (DCA) and trichloroacetate (TCA) are major by-products of drinking water chlorination. Recent experiments have shown that both of these compounds produce hepatic tumors in B6C3F1 mice. There was evidence that these effects may be associated with cytotoxic effects and/or peroxisomal proliferation. Therefore, in the present study the in vitro cytotoxicity of monochloroacetate (MCA), DCA, TCA and a metabolite, glycolate (GLY), was determined in hepatocyte suspensions prepared from naive and clofibric acid-pretreated male Sprague-Dawley rats and B6C3F1 mice. Cytotoxic responses, measured by release of lactic dehydrogenase and/or trypan blue exclusion, were only observed with high concentrations (5.0 mM) of MCA and GLY in hepatocytes from naive animals (p = 0.025 and 0.008, respectively, Sprague-Dawley rat; p = 0.033 and 0.001, respectively, B6C3F1 mouse). The cytotoxic responses to both compounds were observed much earlier and at much lower concentrations in hepatocytes taken from mice and rats that had been pretreated with clofibric acid (p < or = 0.001, Sprague-Dawley rat and B6C3F1 mouse). DCA and TCA produced no evidence of cytotoxicity in hepatocytes from naive or clofibric acid-pretreated animals of either species at concentrations up to 5.0 mM. Increasing concentrations of MCA and GLY resulted in dose-related depletion of intracellular reduced glutathione (GSH) that closely paralleled the cytotoxic responses. Only GLY (0.25-5.0 mM) produced increased intracellular oxidized glutathione. Neither DCA nor TCA was found to alter cellular GSH status in hepatocytes isolated from either Sprague-Dawley rats or B6C3F1 mice. It was concluded from these in vitro observations that DCA and TCA are not highly cytotoxic to hepatocytes. Moreover, the rates of their conversion to MCA or GLY may be insufficient to induce cytotoxic effects in hepatocytes in vivo.

Formation, characterization, and immunoreactivity of lysine thioamide adducts from fluorinated nephrotoxic cysteine conjugates in vitro and in vivo.

Fluorinated nephrotoxic cysteine conjugates undergo bioactivation via the beta-lyase pathway to thionoacetyl fluorides (TAF), the putative reactive intermediates. The TAF derived from S-(1,1,2,2,-tetrafluoroethyl)-L-cysteine (TFEC) difluorothionoacetylates amine nucleophiles found in proteins and lipids. A specific antisera, raised against (trifluoroacetamido)lysine adducts formed in vivo after halothane treatment, has previously been used to localize TFEC-derived protein adducts immunohistochemically, and a good correlation between adduction and toxicity was demonstrated. Interestingly, thioamide formation is facilitated by acyl-transfer catalysts such as imidazoles and phenols. However, although putative lysine adducts have been reported to be formed from the related TAF derived from S-(2-chloro-1,1,2-trifluoroethyl)-L-cysteine (CTFC), protein adducts derived from CTFC metabolism have not been completely characterized. In the present investigation we characterize (chlorofluorothionacetamido)lysine (CFTAL) adduct formation during S-(2-chloro-1,1,2-trifluoroethyl)-L-cysteine (CTFC) metabolism, both in vitro and in vivo. Our data indicate that formation of CTFC-derived lysine thioamides was not as dependent on nucleophilic catalysis as observed for TFEC, and this appears to be due to an apparent greater reactivity of the TAF resulting in a higher trapping efficiency in the absence of catalyst. Also, qualitative and quantitative differences in the structures and time course of CTFC versus TFEC adduct breakdown were observed. Antibodies raised against the halothane metabolite protein adduct (trifluoroacetamido)lysine cross-react with specific mitochondrial proteins from the kidneys of TFEC-treated rats. Using this antibody, we have found that the pattern of adducted proteins from TFEC- and CTFC-treated Fischer rats was similar, but the intensity was considerably lower after treatment with equimolar concentrations of CTFC in vivo.