Molecular markers and targeted therapy of skin rejection in composite tissue allotransplantation.

Skin rejection remains a major hurdle in reconstructive transplantation. We investigated molecular markers of skin rejection with particular attention to lymphocyte trafficking. Skin biopsies (n = 174) from five human hand transplant recipients were analyzed for rejection, characteristics of the infiltrate and lymphocytic adhesion markers. The cellular infiltrate predominantly comprised CD3+ T cells. CD68, Foxp3 and indoleamine 2, 3-dioxygenase expression and the CD4/CD8 increased with severity of rejection. Lymphocyte adhesion markers were upregulated upon rejection, intercellular adhesion molecule-1 and E-selectin correlated best with severity of rejection. Guided by the findings, a specific E- and P-selectin inhibitor was investigated for its effect on skin rejection in a rat hind limb allotransplant model. While efomycine M (weekly s.c. injection into the graft) alone had no effect, long-term allograft survival was achieved when combined with antithymocyte globulin and tacrolimus (control group without efomycine M rejected at postoperative day [POD] 61 +/- 1). Upregulation of lymphocyte trafficking markers correlates with severity of skin rejection and time after transplantation in human hand transplantation. Blocking E- and P-selectin in the skin holds potential to significantly prolong limb allograft survival.

Morphological and functional evaluation of visual disturbances in a bilateral hand allograft recipient.

Allograft recipients are exposed to risks owing to immunosuppression, and there is always the possibility that psychological issues interfere with the procedure's outcomes. An episode of blindness was suspected in a bilateral hand allograft recipient. The patient underwent a multidisciplinary evaluation, and clinical, electrophysiological, laboratory and a combination of functional and morphological magnetic resonance imaging (MRI) tests ruled out any visual process and revealed a secondary benefit, which turned out to be the use of privileges of the transplant support centre for several months. Composite tissue allograft recipients require a thorough psychological assessment before and after transplant procedures to prevent malingering.

Bilateral hand transplantation: result at 20 months.

On November 2006, a bilateral hand allotransplantation was performed for a 47-year-old female who had suffered radiocarpal amputations 28 years before. Technical aspects of the operation are detailed. Alemtuzumab induction, and triple therapy of tacrolimus, mycophenolate mofetil and prednisone were used to control rejection. The evolution of the result and functioning at 20 months are presented in detail. Two acute rejection episodes occurred and were successfully treated with steroids. In addition the patient developed a factitious visual disorder and a facial basal cell carcinoma. Functionally, at 20 months, the patient had a Hand Registry Functional Score of 69 (good), and a DASH score of 19.

Alemtuzumab: key for minimization of maintenance immunosuppression in reconstructive transplantation?

Minimization of immunosuppression has become the key effort in solid organ transplantation. Alemtuzumab, the humanized CD-52 monoclonal antibody, is an effective depleting agent increasingly used in transplantation trials. In this article, we summarize the current experience with alemtuzumab use in hand transplantation and discuss its role in current and future approaches toward minimization of maintenance immunosuppression in reconstructive transplantation.

The Banff 2007 working classification of skin-containing composite tissue allograft pathology.

Composite tissue allotransplantation (CTA) is a recently introduced option for limb replacement and reconstruction of tissue defects. As with other allografts, CTA can undergo immune-mediated rejection; therefore standardized criteria are required for characterizing and reporting severity and types of rejection. This article documents the conclusions of a symposium on CTA rejection held at the Ninth Banff Conference on Allograft Pathology in La-Coruna, Spain, on 26 June 2007, and proposes a working classification, the Banff CTA-07, for the categorization of CTA rejection. This classification was derived from a consensus discussion session attended by the first authors of three published classification systems, pathologists and researchers from international centers where clinical CTA has been performed. It was open to all attendees to the Banff conference. To the extent possible, the format followed the established National Institutes of Health (NIH) guidelines on Consensus Development Programs. By consensus, the defining features to diagnose acute skin rejection include inflammatory cell infiltration with involvement of epidermis and/or adnexal structures, epithelial apoptosis, dyskeratosis and necrosis. Five grades of severity of rejection are defined. This classification refines proposed schemas, represents international consensus on this topic, and establishes a working collective classification system for CTA reporting of rejection in skin-containing CTAs.

Infrared photodetectors in heterostructure nanowires.

We report on spectrally resolved photocurrent measurements on single self-assembled nanowire heterostructures. The wires, typically 3 microm long with an average diameter of 85 nm, consist of InAs with a 1 microm central part of InAsP. Two different sets of wires were prepared with phosphorus contents of 15+/-3% and 35+/-3%, respectively, as determined by energy-dispersive spectroscopy measurements made in transmission electron microscopy. Ohmic contacts are fabricated to the InAs ends of the wire using e-beam lithography. The conduction band offset between the InAs and InAsP regions virtually removes the dark current through the wires at low temperature. In the optical experiments, interband excitation in the phosphorus-rich part of the wires results in a photocurrent with threshold energies of about 0.65 and 0.82 eV, respectively, in qualitative agreement with the expected band gap of the two compositions. Furthermore, a strong polarization dependence is observed with an order of magnitude larger photocurrent for light polarized parallel to the wire than for light polarized perpendicular to the wire. We believe that these wires form promising candidates as nanoscale infrared polarization-sensitive photodetectors.

The effect of soybean soapstock on the quality parameters and fatty acid composition of the hen egg yolk.

The effects of increasing proportions of soybean soapstock (SSS) in laying hen diets on egg quality parameters and on the fatty acid (FA) composition of the yolk were studied. One hundred sixty Babcock B-300 x laying hens, 20 wk of age, were allotted to 5 dietary treatments comprising a control diet (D5) with soybean oil at 100% or SSS in proportions of 25% (D1), 50% (D2), 75% (D3), and 100% (D4) replacing the oil source in commercial-type diets throughout the 15-wk laying period. Egg quality parameters were recorded weekly. Four pooled yolks for each treatment were collected at 0, 9, and 15 wk, and their FA profiles were determined. Egg weight, shell thickness, shape index, and Haugh unit were not influenced by dietary treatment. The concentrations of saturated FA (SFA) in yolks were generally kept at a constant level, regardless of the percentage of SSS in the hen diets. Total monounsaturated FA (MUFA) content did not vary over the course of the experiment, except for C14:1. After 15 wk of feeding, the total polyunsaturated FA (PUFA) n-3 increased in yolks of all diets. Among the long-chain PUFA, the percentage of C20:4 (arachidonic acid) was less affected. Inclusion of 100% SSS allowed production of eggs with similar PUFA/SFA and n-6/n-3 ratios when compared with eggs from hens fed D5. As SSS represents one-third of the oil cost, its inclusion in layer diets could represent an important economic benefit.

Organochlorine pesticide residues in cow's milk from a tropical region of Mexico.

A monitoring study was conducted to assess the magnitude of DDT [(1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane)] and HCH (hexachlorocyclohexane) contamination of bovine milk from the central tropical region of Mexico as the chemicals are extensively used in livestock and public-health programmes. Among pesticide residues analysed, the milk samples collected from Tlalixcoyan showed a mean level of gamma-HCH (0.128 mg x kg(-1)), which was significantly higher than residues in milk samples from Medellin (0.049 mg x kg(-1)) and Paso San Juan (0.022 mg x kg(-1)). The mean level of pp'-DDE in Medellin samples (0.039 mg x kg(-1)) was significantly higher than in Paso San Juan (0.018 mg x kg(-1)) and Tlalixcoyan (0.024 mg x kg(-1)) milk samples. The pp'-DDT mean level from Medellin milk samples (0.089 mg x kg(-1)) was significantly higher than the levels detected in the other two areas. The highest mean Sigma-DDT level detected in Medellin samples (0.146 mg x kg(-1)) was three times the FAO/WHO tolerance level. The highest acceptable daily intakes calculated for Sigma-DDT were 0.017 microg x kg(-1) bw day(-1) for adults and 0.530 microg x kg(-1) bw day(-1) for infants; for gamma-HCH residues, they were 0.021 microg x kg(-1) bw day(-1) for adults and 0.666 microg x kg(-1) bw day(-1) for infants, indicating that infants are more exposed to pesticide residues. Results indicate that cattle exposure to HCH and DDT results in high levels in dairy milk and a potential health risk for consumers.

The effect of acidified soapstocks on feed conversion and broiler skin pigmentation.

The effect of different soapstocks (corn, sunflower, canola, and soybean) on productive performance and skin broiler pigmentation was investigated. Soapstock was added to reach 1.0% polyunsaturated fatty acids in the diet. The addition of soybean soapstock significantly improved live body weight gain of the birds from 1 to 7 wk of age. A live body weight gain of 1,736 g/bird was calculated for broilers fed with the soybean soapstock diet. Feed conversion was significantly higher for broilers fed with the soybean soapstock diet, and no negative effect was observed. Compared to broilers fed with Pixtafil (100.0% pigmentation), those fed soybean soapstock (when added as a supplement of 1.0% polyunsaturated fatty acids in the diet) reached 48.0% pigmentation, and those fed corn soapstock reached only 7.3%. When the diets were complemented with Pixtafil to reach 100% of calculated pigmentation, the soybean soapstock diet reached 100.8% pigmentation compared to a canola soapstock diet that reached 72.0% pigmentation. Acidified soybean soapstock could be a source of polyunsaturated fatty acids and of xantophyl pigments in broiler feeding.

Decreasing incidence of fractures in children: an epidemiological analysis of 1,673 fractures in Malmö, Sweden, 1993-1994.

The incidence of fractures in children in the city of Malmö, Sweden, almost doubled between 1950 and 1979. To see whether a further increase had occurred, we carried out an epidemiological analysis of fractures among children 0-16 years in Malmö 1993-1994. During the study period, 1,673 fractures occurred in 1,610 children. The commonest fracture location was the distal forearm (26%), followed by the phalanges of the hand (16%) and the clavicle (9%). The annual fracture incidence was 235/10(4) in boys, 149/10(4) in girls and 193/10(4) for both genders. This means a decrease in the annual fracture incidence by 9% since 1975-1979. The decrease was not associated with any specific type of fracture or etiological factor. Fractures of the distal forearm among girls were an exception to the general decline, having increased by one third since 1975-1979, which might be explained by the fact that today girls participate to a greater extent in the same sports as boys.

Optical studies of individual InAs quantum dots in GaAs: few-particle effects

Optical emission from individual strained indium arsenide (InAs) islands buried in gallium arsenide (GaAs) was studied. At low excitation power density, the spectra from these quantum dots consist of a single line. At higher excitation power density, additional emission lines appeared at both higher and lower energies, separated from the main line by about 1 millielectron volt. At even higher excitation power density, this set of lines was replaced by a broad emission peaking below the original line. The splittings were an order of magnitude smaller than the lowest single-electron or single-hole excited state energies, indicating that the fine structure results from few-particle interactions in the dot. Calculations of few-particle effects give splittings of the observed magnitude.

[Septic shock and nitric oxide]. / Shock séptico y óxido nítrico.

Refractory hypotension is the main cause of death of patients with septic shock. It has been shown that an excessive release of NO is responsible for the sepsis-induced hypotension and vascular hyporeactivity. Nitric oxide is produced under normal conditions by a constitutive enzyme present, among other cell types, in the endothelial cell, and is necessary for maintenance of normal organ perfusion. Under inflammatory or septic conditions, a new enzyme is expressed in phagocytic cells and vascular smooth muscle cells, giving rise to an uncontrolled NO production that is associated with cytotoxic effects and vasodilatation. Randomized clinical trials have shown that the administration of inhibitors of NO synthesis to patients with septic shock is associated with a greater incidence of shock resolution, without significant adverse effects. The recent discovery of the different biological functions of NO, both under normal and inflammatory conditions, has allowed the development of new concepts about the pathophysiology of septic shock, and has provided the bases to design novel therapeutic strategies for the treatment of septic shock, based on the inhibition of NO synthesis.

Epidemiology of children's fractures.

Fractures constitute 10% to 25% of all pediatric injuries and are more common in boys than in girls, and after age 13 or 14 years are twice as common. The results from an epidemiologic study in Malmö indicate that a child's risk of sustaining a fracture is 42% in boys and 27% in girls from birth to age 16 years. Fractures of the distal end of the radius are the most common injury, followed by fractures of the phalanges of the hand. From 1950 to 1979 there was a twofold increase in the risk of fracture, due to an increase in light-energy trauma, mainly sporting activities. Since the end of the 1970s there has been no further increase in the fracture risk. The data also indicate that preventive measures have been effective in decreasing severe accidents.

Testicular arginine vasopressin in the developing rat: a possible physiological role.

Testicular immunoreactive arginine vasopressin (irAVP) has been shown to inhibit testosterone production by the Leydig cell in vitro. We studied pre- and postpubertal rats and the results are in agreement with the notion that such inhibition might occur in vivo and, therefore, could have physiological significance. Testicular irAVP and serum testosterone levels were measured in 14-, 21-, 28-, 35-, 42-, and 70-day-old rats. The testicular irAVP concentration was lowest in early prepubertal rats, increased significantly to the highest level at 35 days, then decreased at 42 days, and plateaued at 70 days of age. A pubertal increase in serum testosterone was observed at 42 days when AVP was decreasing. Thus, an inverse relationship was observed at the onset of pubertal maturation. These parameters were also measured in 3 groups of rats 1 week after hemicastration which was performed at the ages of 28, 35 and 70 days. In the 28-day-old rats there was a significant decrease in irAVP 1 week later, in contrast to the intact animal, whereas hemicastration performed at 35 and 70 days of age had no impact on irAVP. Our data suggest that the role of AVP may be physiologically relevant during the peripubertal period of testicular maturation in the rat.

Pituitary-thyroid function in patients with septic shock and its relation with outcome.

OBJECTIVE: To study the time course of thyroid function abnormalities and their relation to outcome in patients with septic shock. DESIGN: Prospective study in a cohort of consecutive patients. SETTING: Intensive Care Unit in a University Hospital. PATIENTS AND METHODS: We studied 27 patients (mean age 50 +/- 19 years, Apache II score 18.4 +/- 5.2, 15 survivors) diagnosed of septic shock. Total T4 (T4) and total T3 (T3) (RIA) were determined on days 1 and 5 after admission. We also measured TSH (ultrasensitive RIA) at 08.00, 20.00 and 01.00 hours (on days 1 and 5), and the TSH response to TRH (400 microg intravenous) on days 2 and 6. Data are mean +/- SD. RESULTS: Whereas low thyroid hormones concentrations were present on day 1 in all patients, only survivors presented a significant increase in T3 and T4 on day 5. Basal TSH levels and the area under the curve of the TSH response to TRH on day 2 were significantly higher in survivors than in non survivors (0.89 +/- 0.63 vs. 0.34 +/- 0.42 microIU/ml, and 229 + 157 vs. 101 + 101). The normal nocturnal (01.00 hr) surge of TSH (the difference between TSH concentrations at 8 am and at 1 am) was abolished in both survivors and non survivors on day 1 but it was recovered on day 5 only in survivors. CONCLUSIONS: Our data indicate that patients with septic shock present an altered hypothalamic-pituitary-thyroid axis, and that survivors thyroid function differs from that of non survivors shortly after diagnosis. Survivors are characterised by a greater TSH response to TRH, indicating a less deranged hypothalamic-pituitary-thyroid axis. Thyroid function improves in survivors, but not in non survivors, during the course of their illness.

Identification and characterization of glima 38, a glycosylated islet cell membrane antigen, which together with GAD65 and IA2 marks the early phases of autoimmune response in type 1 diabetes.

Immunoprecipitating IgG autoantibodies to glutamic acid decarboxylase, GAD65, and/or a tyrosine phosphatase, IA2, are present in the majority of individuals experiencing pancreatic beta cell destruction and development of type 1 diabetes. Here we identify a third islet cell autoantigen, a novel 38-kD protein, which is specifically immunoprecipitated with sera from a subset of prediabetic individuals and newly diagnosed type 1 diabetic patients. The 38-kD autoantigen, named glima 38, is an amphiphilic membrane glycoprotein, specifically expressed in islet and neuronal cell lines, and thus shares the neuroendocrine expression patterns of GAD65 and IA2. Removal of N-linked carbohydrates results in a protein of 22,000 Mr. Glima 38 autoantibodies were detected in 16/86 (19%) of newly diagnosed patients, including three very young children, who had a rapid onset of disease, and in 6/44 (14%) of prediabetic individuals up to several years before clinical onset. The cumulative incidence of GAD65 and glima 38 antibodies in these two groups was 83 and 80%, respectively, and the cumulative incidence of GAD65, glima 38, and IA2 antibodies in the same groups was 91 and 84%, respectively. GAD65, IA2, and glima 38 represent three distinct targets of immunoprecipitating IgG autoantibodies associated with beta cell destruction and type 1 diabetes.

Effects of nitric oxide synthase inhibition on the cardiovascular response to low output shock.

OBJECTIVE: To study the role of nitric oxide in the cardiovascular response to a model of a low output syndrome. DESIGN: Prospective animal study. SETTING: Animal research laboratory. SUBJECTS: Sheep anesthetized with pentobarbital, mechanically ventilated, and monitored with pulmonary arterial and peripheral arterial catheters. INTERVENTIONS: A low output state was induced by inflating a balloon-tip catheter placed in the right atrium. Cardiac index was maintained at 1 L/min/m2 throughout the experiment in three groups of sheep: a) control (n=6) b)LNNA group (pretreated with the nitric oxide synthase inhibitor N omega-nitro-L-arginine [LNNA, 100 mg/kg, iv bolus, n=6); and c) dexamethasone group (pretreated with dexamethasone (6 mg/kg, intravenous bolus, n=6). Dexamethasone is an inhibitor of the induction of nitric oxide synthase. LNNA or dexamethasone were administered 15 mins before inducing the low output state. MEASUREMENTS AND MAIN RESULTS: Hemodynamic and oxygen transport variables, and plasma lactate and pyruvate concentrations, were measured at baseline and during the next 3 hrs. For a comparable decrease in cardiac index and oxygen delivery in all groups, the LNNA group had less hypotension and a more marked increase in systemic vascular resistance as compared with the control group. Oxygen consumption and oxygen extraction were higher in the LNNA group as compared with the control group at 30 and 60 mins. Plasma lactate concentration increased significantly less in the LNNA group than in the control and the dexamethasone groups during the observation period. CONCLUSIONS: Inhibition of nitric oxide synthesis during a severe low output state in sheep is associated with a better hemodynamic response, as evidenced by a greater vasoconstriction, and signs of less marked tissue hypoxia. It is likely that inhibition of nitric oxide synthesis in this model leads to an imbalance between the tonic relaxing action of nitric oxide and the influences of vasoconstrictor agents.