Aortic graft preservation by debridement and omental wrapping.

BACKGROUND: Aortic graft infection is a rare, but grave, complication in vascular surgery. Graft removal together with extra-anatomical bypass or in situ graft replacement is usually advocated, but these procedures are associated with significant morbidity and mortality. METHODS AND RESULTS: Two cases of aortic graft infection in high-risk surgical candidates managed by open debridement and omental wrapping with graft preservation are described. Both remain well at 3 years without any adjunctive procedures. CONCLUSION: Debridement and omental wrapping may offer an alternative to graft removal and revascularization in selected patients. This relatively low-risk procedure may allow long-term survival.

Isolated right testicular pain for six days: an unusual presentation of occult abdominal aortic aneurysm leak.

Abdominal aortic aneurysm (AAA) rupture commonly presents with abdominal or lower back pain and haemodynamic instability. There have been case reports of co-existing left testicular pain;(1) however, very few cases describe right testicular pain as the sentinel symptom. We discuss the case of a 75-year-old man who presented to the on-call urologists with a 6-day history of right testicular pain. On examination, a painless AAA was detected. The patient was stable and a CT scan demonstrated a large AAA extending into the right iliac vessels, with suggestion of leakage. Attempted emergency repair was unsuccessful and the patient died in theatre. This atypical presentation of occult aneurysm leak highlights the need for clinical vigilance in the older patient with seemingly benign groin symptoms, including isolated right testicular pain.

Risk factors for chronic ulceration in patients with varicose veins: a case control study.

BACKGROUND/OBJECTIVE: Identifying which patients with varicose veins are at risk of progressing to more severe forms of chronic venous disease could help in assigning clinical priorities and targeting appropriate treatments. The aim of this study was to determine, in subjects with varicose veins, the characteristics of venous disease and other factors associated with an increased risk of ulceration. METHODS: One hundred twenty subjects with varicose veins and an open or healed venous leg ulcer were compared with 120 controls with varicose veins and no history of venous ulcer on this case control study. Subjects were recruited from hospital settings and primary care. Each subject completed a questionnaire on lifestyle and medical history and underwent an examination comprising of clinical classification of venous disease (CEAP), duplex scanning, quantitative digital photoplethysmography, and measurement of dorsiflexion. Multiple logistic regression analyses and calculation of receiver operating characteristic (ROC) curves were performed to identify the combination of factors which most accurately predicted which patients with varicose veins will develop leg ulcers. RESULTS: An increased risk of ulceration was associated with the severity of clinical venous disease, especially with the presence of skin changes (P < .0001). Other significant risk factors included history of deep vein thrombosis (DVT) (P = .001), higher body mass index (BMI) (P = .006), smoking (P = .009), and reflux in the deep veins (P = .0001). Ulceration was associated with reduced volume of blood displaced as reflected by photoplethysmography and a limited range of ankle movement (not wholly due to the effects of an active ulcer) (both P < .05). Multivariate analyses showed that skin changes including lipodermatosclerosis (odds ratio [OR] 8.90, 95% confidence interval [CI] 1.44-54.8), corona phlebectatica (OR 4.52, 95% CI 1.81-11.3) and eczema (OR 2.87, 95% CI 1.12-7.07), higher BMI (OR 1.08, 95% CI 1.01-1.15), and popliteal vein reflux (OR 2.82, 95% CI 1.03-7.75) remained independently associated with increased risk of ulceration while good dorsiflexion of the ankle (OR 0.88, 95% CI 0.81-0.97) and an effective calf muscle pump (OR 0.96, 95% CI 0.92-0.99) remained protective factors. ROC curve analyses indicated that a model based on clinical observation of skin changes, duplex scanning for popliteal reflux, and calf muscle pump tests would be the most accurate in determining which patients with varicose veins develop leg ulcers. CONCLUSIONS: The results of this study confirm that, in patients with varicose veins, those with skin changes of chronic venous insufficiency and deep vein incompetence are at greatly increased risk of ulceration. However, the risks may also be increased in those who smoke, are obese, and have restricted ankle movement and reduced calf muscle pump power.

Hypervalent versus nonhypervalent carbon in noble-gas complexes.

Silicon in [Cl--SiH(3)--Cl](-) is hypervalent, whereas carbon in [Cl--CH(3)--Cl](-) is not. We have recently shown how this can be understood in terms of the ball-in-a-box model, according to which silicon fits perfectly into the box that is constituted by the five substituents, whereas carbon is too small and, in a sense, "drops to the bottom" of the box. But how does carbon acquire hypervalency in the isostructural and isoelectronic noble gas (Ng)/methyl cation complexes [Ng--CH(3)--Ng](+) (Ng=He and Ne), which feature a delocalized D(3h)-symmetric structure with two equivalent C--Ng bonds? From Ng=Ar onwards, the [Ng--CH(3)--Ng](+) complex again acquires a propensity to localize one of its axial C--Ng bonds and to largely break the other one, and this propensity increases in the order Ng=Ar

Aromaticity and antiaromaticity in 4-, 6-, 8-, and 10-membered conjugated hydrocarbon rings.

Recently, we presented a molecular orbital (MO) model of aromaticity that explains, in terms of simple orbital-overlap arguments, why benzene (C(6)H(6)) has a regular structure with delocalized double bonds whereas the geometry of 1,3-cyclobutadiene (C(4)H(4)) is distorted with localized double bonds. Here, we show that the same model and the same type of orbital-overlap arguments also account for the irregular and regular structures of 1,3,5,7-cyclooctatetraene (C(8)H(8)) and 1,3,5,7,9-cyclodecapentaene (C(10)H(10)), respectively. Our MO model is based on accurate Kohn-Sham DFT analyses of the bonding in C(4)H(4), C(6)H(6), C(8)H(8), and C(10)H(10) and how the bonding mechanism is affected if these molecules undergo geometrical deformations between regular, delocalized ring structures and distorted ones with localized double bonds. The propensity of the pi electrons is always to localize the double bonds, against the delocalizing force of the sigma electrons. Importantly, we show that the pi electrons nevertheless determine the localization (in C(4)H(4) and C(8)H(8)) or delocalization (in C(6)H(6) and C(10)H(10)) of the double bonds.

One-stage repair of an aortic dissection and aortic coarctation.

Ascending aortic dissection with aortic coarctation has a high mortality. There are few reports of successful surgical management of the combined condition. We report a case of a successful one-stage repair of type A aortic dissection with aortic coarctation, using an extra-anatomic bypass to connect the ascending to the abdominal aorta.

Hypervalent silicon versus carbon: ball-in-a-box model.

Why is silicon hypervalent and carbon not? Or why is [Cl-CH(3)-Cl](-) labile with a tendency to localize one of its axial C-Cl bonds and to largely break the other one, while the isostructural and isoelectronic [Cl-SiH(3)-Cl](-) forms a stable pentavalent species with a delocalized structure featuring two equivalent Si-Cl bonds? Various hypotheses have been developed over the years focusing on electronic and steric factors. Here, we present the so-called ball-in-a-box model, which tackles hypervalence from a new perspective. This model reveals the key role of steric factors and provides a simple way of understanding the above phenomena in terms of different atom sizes. Our bonding analyses are supported by computation experiments in which we probe, among other things, the shape of the S(N)2 potential-energy surface of Cl(-) attacking a carbon atom in the series of substrates CH(3)Cl, (.)CH(2)Cl, (..)CHCl, and (...)CCl. Our findings for ClCH(3)Cl(-) and ClSiH(3)Cl(-) are generalized to other Group 14 central atoms (Ge, Sn, and Pb) and axial substituents (F).

Aromaticity: molecular-orbital picture of an intuitive concept.

Geometry is one of the primary and most direct indicators of aromaticity and antiaromaticity: a regular structure with delocalized double bonds (e.g., benzene) is symptomatic of aromaticity, whereas a distorted geometry with localized double bonds (e.g., 1,3-cyclobutadiene) is characteristic of antiaromaticity. Here, we present a molecular-orbital (MO) model of aromaticity that explains, in terms of simple orbital-overlap arguments, why this is so. Our MO model is based on accurate Kohn-Sham DFT analyses of the bonding in benzene, 1,3-cyclobutadiene, cyclohexane, and cyclobutane, and how the bonding mechanism is affected if these molecules undergo geometrical deformations between regular, delocalized ring structures, and distorted ones with localized double bonds. We show that the propensity of the pi electrons is always, that is, in both the aromatic and antiaromatic molecules, to localize the double bonds, against the delocalizing force of the sigma electrons. More importantly, we show that the pi electrons nevertheless decide about the localization or delocalization of the double bonds. A key component of our model for uncovering and resolving this seemingly contradictory situation is to analyze the bonding in the various model systems in terms of two interpenetrating fragments that preserve, in good approximation, their geometry along the localization/delocalization modes.

Functional outcome after open repair of ruptured abdominal aortic aneurysm.

BACKGROUND: Outcome after operative repair of ruptured abdominal aortic aneurysm (AAA) has traditionally been assessed in terms of survival. This study examines the functional outcome of patients who survive operation. METHODS: Consecutive patients who survived open repair over an 18-month period were entered into a prospective case-control study. Age- and sex-matched controls were identified from patients undergoing elective AAA repair. The Short Form-36 health survey was administered to both groups of patients at 6 months after operation. Results were compared with the expected scores for an age- and sex-matched normal UK population. RESULTS: Fifty-seven patients underwent open repair of a ruptured AAA, and 30 survived; no patient was lost to follow-up. There were no significant differences in quality of life between patients who had an emergency repair and those who had an elective repair. Both of these groups had poorer health-related quality of life outcomes than the matched normal population. Surprisingly, compared with the normal population, patients after elective repair had poorer outcomes in more health domains than patients who survived emergency operation. CONCLUSIONS: Survivors of ruptured AAA repair have a good functional outcome within 6 months of operation.

Subungual leukemia cutis.

A 79-year-old man had generalized humping of the nails and subungual tumors involving several fingers and the left big toe. Findings on histologic study of the tumor, together with the pattern on the peripheral blood smear, established the diagnosis of chronic lymphocytic leukemia. To the best of our knowledge, this is the first reported case of chronic lymphocytic leukemia involving the subungual area. The authors' observation emphasizes the importance of taking a biopsy specimen in the differential diagnosis of subungual tumors.

A simple and accurate cryosurgical tool for the treatment of benign skin lesions: the "hard tail" dip-stick.

Although widely used, cryosurgery with liquid nitrogen still has its difficulties. Too often, large swabs sprayers, and cryoprobes damage surrounding skin. Small swabs are inadequate because of their limited "reservoir" capacity. This article describes a new tool, namely the "hard tail" dip-stick, which has been devised in an attempt to avoid these inadequacies.

Bullous pemphigoid and glomerulonephritis. Report of four cases.

We report on four patients with bullous pemphigoid and other autoimmune diseases who had or developed glomerulonephritis. The relationship between these two immunologic disorders involving the basement membrane is discussed. Our data suggest a coincidental phenomenon in patients who successively or concurrently have multiple diseases of autoimmunity.

[Malignant blue nevus]. / Naevus bleu malin.

Malignant blue naevi with an aggressive behaviour are rare tumours. To our knowledge, this is the first reported case who has developed generalized skin melanosis and melanuria in its terminal stage.

[Heparin treatment. Comparison between intravenous and subcutaneous administration]. / Traitement héparinique. comparaison entre les voies d'administration intraveineuse et sous-cutanée.

48 patients with acute deep venous thrombosis of the lower limbs were treated with sodium heparin. In 23 patients heparin was injected subcutaneously (s.c.) twice a day and in 25 patients heparin was given by continuous intravenous perfusion (i.v.). Pain and edema disappeared after 8.7 days (s.c.) and 11.7 days (i.v.) respectively. One non fatal pulmonary embolism occurred in each group. A second venography was performed in 24 patients after 7 days of treatment and revealed no difference between the two groups. As judged by repeated thrombin time determination, anticoagulation was ineffective on at least one day in 39% of patients treated subcutaneously and in 60% of patients treated intravenously. The two pulmonary embolisms occurred in patients with ineffective anticoagulation. It is concluded that heparin may be used either intravenously or subcutaneously in the treatment of acute deep venous thrombosis. Thromboembolic complications occurred with both methods of treatment when anticoagulation was ineffective.