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1.
J Chem Phys ; 147(23): 234501, 2017 Dec 21.
Article in English | MEDLINE | ID: mdl-29272922

ABSTRACT

The monohydroxy alcohol 2-ethyl-1-hexanol mixed with the halogen-substituted alkyl halides 2-ethyl-1-hexyl chloride and 2-ethyl-1-hexyl bromide was studied using synchrotron-based x-ray scattering. In the diffraction patterns, an oxygen-related prepeak appears. The concentration dependence of its intensity, shape, and position indicates that the formation of the hydrogen-bonded associates of monohydroxy alcohols is largely hindered by the halogen alkane admixture. Using dielectric spectroscopy and high-resolution rheology on the same liquid mixtures, it is shown that these structural features are correlated with the relaxation mechanisms giving rise to supramolecular low-frequency dynamics.

2.
Nanotechnology ; 27(42): 425702, 2016 Oct 21.
Article in English | MEDLINE | ID: mdl-27622774

ABSTRACT

We report on a high resolution x-ray diffraction study unveiling the effect of carriers optically injected into (In,Ga)As quantum dots on the surrounding GaAs crystal matrix. We find a tetragonal lattice expansion with enhanced elongation along the [001] crystal axis that is superimposed on an isotropic lattice extension. The isotropic contribution arises from excitation induced lattice heating as confirmed by temperature dependent reference studies. The tetragonal expansion on the femtometer scale is tentatively attributed to polaron formation by carriers trapped in the quantum dots.

3.
J Chem Phys ; 141(22): 22D506, 2014 Dec 14.
Article in English | MEDLINE | ID: mdl-25494777

ABSTRACT

The influence of high hydrostatic pressure on the structure and protein-protein interaction potential of highly concentrated lysozyme solutions up to about 370 mg ml(-1) was studied and analyzed using small-angle X-ray scattering in combination with a liquid-state theoretical approach. In the concentration region below 200 mg ml(-1), the interaction parameters of lysozyme solutions are affected by pressure in a nonlinear way, which is probably due to significant changes in the structural properties of bulk water, i.e., due to a solvent-mediated effect. Conversely, for higher concentrated protein solutions, where hydration layers below ∼4 water molecules are reached, the interaction potential turns rather insensitive to compression. The onset of transient (dynamic) clustering is envisaged in this concentration range. Our results also show that pressure suppresses protein nucleation, aggregation and finally crystallization in supersaturated condensed protein solutions. These findings are of importance for controlling and fine-tuning protein crystallization. Moreover, these results are also important for understanding the high stability of highly concentrated protein solutions (as they occur intracellularly) in organisms thriving under hydrostatic pressure conditions such as in the deep sea, where pressures up to the kbar-level are reached.


Subject(s)
Muramidase/chemistry , Water/chemistry , Animals , Chickens , Crystallization , Hydrostatic Pressure , Protein Aggregates , Protein Conformation , Scattering, Small Angle , X-Ray Diffraction
4.
Nanotechnology ; 24(16): 165701, 2013 Apr 26.
Article in English | MEDLINE | ID: mdl-23535465

ABSTRACT

Temperature induced changes of the local chemical structure of bulk amorphous GexSiOy are studied by Ge K-edge x-ray absorption near-edge spectroscopy and Si L2/3-edge x-ray Raman scattering spectroscopy. Different processes are revealed which lead to formation of Ge regions embedded in a Si oxide matrix due to different initial structures of as-prepared samples, depending on their Ge/Si/O ratio and temperature treatment, eventually resulting in the occurrence of nanocrystals. Here, disproportionation of GeOx and SiOx regions and/or reduction of Ge oxides by pure Si or by a surrounding Si sub-oxide matrix can be employed to tune the size of Ge nanocrystals along with the chemical composition of the embedding matrix. This is important for the optimization of the electronic and luminescent properties of the material.

5.
Surgeon ; 11(6): 295-9, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23510704

ABSTRACT

UNLABELLED: Renal cell carcinoma (RCC) propagates into the IVC in 4% of cases with 1% extending into the right atrium. Radical surgical resection remains the definitive curative/palliative treatment in those without significant metastases. The aim was to review our experience in patients with different levels of IVC involvement, cardiopulmonary bypass (CPB) and perioperative/long term outcomes. PATIENTS AND METHODS: From 2001 to 2012, 24 radical nephrectomies with IVC thrombectomy were performed. A retrospective chart review was undertaken to record demographics, presenting symptoms, duration of surgery, peri-operative transfusion, CPB and peri-operative complications, tumour grade/stage, and patient survival. RESULTS: We identified 24 patients (18 male, Age median 59 range 35-78). The commonest presenting symptoms were weight loss, pain and haematuria. The majority of tumours were right sided (n = 17) with 8 having lung metastases at presentation. Thrombus level was 16 (infradiaphragmatic), 2 (supradiaphragmatic), 6 (intra-atrial). 15 patients required sternotomy for vascular control and 9 required CPB both with a significantly longer operative time compared (6.1 ± 3.5 vs. 7.2 ± 1.2 vs. 3.5 ± 1.1 h, respectively). Peri-operative complications (n = 21) included cardiopulmonary, renal, gastrointestinal and septic problems. There were 2 peri-operative deaths. Blood transfusion was significantly less in those not requiring sternotomy or CPB using the "Cell Saver" device. The majority were Fuhrman grade 3 (n = 16) and clear cell type (n = 14). Overall 3-year survival was 100% (Laparotomy only), 40% (sternotomy + cross-clamp), and 20% (CPB). CONCLUSIONS: IVC thrombectomy has significant morbidity and requires careful patient selection and a multi-disciplinary approach to optimise patient outcomes. In this series, the level of IVC thrombus and requirement for CPB directly affects patient morbidity and outcome.


Subject(s)
Carcinoma, Renal Cell/surgery , Heart Atria , Heart Diseases/etiology , Kidney Neoplasms/surgery , Thrombectomy/methods , Thrombosis/etiology , Vena Cava, Inferior , Adult , Aged , Carcinoma, Renal Cell/complications , Carcinoma, Renal Cell/diagnosis , Cardiopulmonary Bypass/methods , Female , Follow-Up Studies , Forecasting , Heart Diseases/diagnosis , Heart Diseases/surgery , Humans , Kidney Neoplasms/complications , Kidney Neoplasms/diagnosis , Male , Middle Aged , Neoplastic Cells, Circulating/pathology , Nephrectomy , Patient Selection , Retrospective Studies , Thrombosis/diagnosis , Thrombosis/surgery , Treatment Outcome
6.
J Mol Cell Cardiol ; 52(1): 148-53, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22008391

ABSTRACT

The objective of this study was to investigate the nature and biomechanical properties of collagen fibers within the human myocardium. Targeting cardiac interstitial abnormalities will likely become a major focus of future preventative strategies with regard to the management of cardiac dysfunction. Current knowledge regarding the component structures of myocardial collagen networks is limited, further delineation of which will require application of more innovative technologies. We applied a novel methodology involving combined confocal laser scanning and atomic force microscopy to investigate myocardial collagen within ex-vivo right atrial tissue from 10 patients undergoing elective coronary bypass surgery. Immuno-fluorescent co-staining revealed discrete collagen I and III fibers. During single fiber deformation, overall median values of stiffness recorded in collagen III were 37±16% lower than in collagen I [p<0.001]. On fiber retraction, collagen I exhibited greater degrees of elastic recoil [p<0.001; relative percentage increase in elastic recoil 7±3%] and less energy dissipation than collagen III [p<0.001; relative percentage increase in work recovered 7±2%]. In atrial biopsies taken from patients in permanent atrial fibrillation (n=5) versus sinus rhythm (n=5), stiffness of both collagen fiber subtypes was augmented (p<0.008). Myocardial fibrillar collagen fibers organize in a discrete manner and possess distinct biomechanical differences; specifically, collagen I fibers exhibit relatively higher stiffness, contrasting with higher susceptibility to plastic deformation and less energy efficiency on deformation with collagen III fibers. Augmented stiffness of both collagen fiber subtypes in tissue samples from patients with atrial fibrillation compared to those in sinus rhythm are consistent with recent published findings of increased collagen cross-linking in this setting.


Subject(s)
Collagen Type III/metabolism , Collagen Type I/metabolism , Phenotype , Ventricular Remodeling , Aged , Atrial Fibrillation/metabolism , Collagen Type I/ultrastructure , Collagen Type III/ultrastructure , Female , Humans , Male , Microscopy, Atomic Force , Middle Aged
7.
Ir Med J ; 103(2): 55-7, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20666059

ABSTRACT

A 63-year-old male presented with sudden onset chest pain and dyspnoea following a kick to the praecordium while gelding a horse. Transthoracic echocardiography showed evidence of flail tricuspid valve leaflets, severe tricuspid regurgitation and a widely patent foramen ovale with a right-to-left shunt. Due to progressive severe systemic hypoxemia the patient underwent emergent surgical intervention. Operative findings confirmed rupture of the anterior and septal tricuspid valve papillary muscles. Successful papillary muscle reattachment was performed in association with tricuspid annuloplasty and suture closure of his patent foramen ovale. Disruption of the tricuspid valve is well described as consequence of blunt trauma to the chest wall and is often well tolerated, coming to light many years post injury. Valve disruption due to rupture at the papillary muscle level, however, typically results in greater severity of tricuspid regurgitation and the abrupt rise in right intra-atrial pressure may lead to a right-to-left shunt across a patent foramen ovale. Where hemodynamic compromise ensues, prompt surgical intervention is mandated.


Subject(s)
Heart Injuries/etiology , Papillary Muscles/injuries , Tricuspid Valve Insufficiency/etiology , Wounds, Nonpenetrating/complications , Animals , Horses , Humans , Male , Middle Aged , Prolapse
8.
QJM ; 112(9): 663-667, 2019 Sep 01.
Article in English | MEDLINE | ID: mdl-31147713

ABSTRACT

BACKGROUND: Infective endocarditis (IE) is a potentially life-threatening infection of the heart's endocardial surface. Despite advances in the diagnosis and management of IE, morbidity and mortality remain high. AIM: To characterize the demographics, bacteriology and outcomes of IE cases presenting to an Irish tertiary referral centre. DESIGN: Retrospective cohort study. METHODS: Patients were identified using Hospital Inpatient Enquiry and Clinical Microbiology inpatient consult data, from January 2005 to January 2014. Patients were diagnosed with IE using Modified Duke Criteria. Standard Bayesian statistics were employed for analysis and cases were compared to contemporary international registries. RESULTS: Two hundred and two patients were diagnosed with IE during this period. Mean age 54 years. Of these, 136 (67%) were native valve endocarditis (NVE), 50 (25%) were prosthetic valve endocarditis (PVE) and 22 (11%) were cardiovascular implantable electronic device-associated endocarditis. Culprit organism was identified in 176 (87.1%) cases and Staphylococcal species were the most common (57.5%). Fifty-nine per cent of NVE required surgery compared to 66% of PVE. Mean mortality rate was 17.3%, with NVE being the lowest (12.5%) and PVE the highest (32%). Increasing age was also associated with increased mortality. Fifty-three (26.2%) patients had embolic complications. CONCLUSIONS: This Irish cohort exhibited first-world demographic patterns comparable to those published in contemporary international literature. PVE required surgery more often and was associated with higher rates of mortality than NVE. Embolic complications were relatively common and represent important sequelae, especially in the intravenous drug user population. It is also pertinent to aggressively treat older cohorts as they were associated with increased mortality.


Subject(s)
Endocarditis/epidemiology , Endocarditis/mortality , Heart Valve Prosthesis/adverse effects , Prosthesis-Related Infections/epidemiology , Prosthesis-Related Infections/mortality , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Bacterial Infections/epidemiology , Bacterial Infections/mortality , Bayes Theorem , Female , Hospital Mortality , Humans , Ireland/epidemiology , Male , Middle Aged , Retrospective Studies , Substance Abuse, Intravenous/complications , Tertiary Care Centers , Young Adult
9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 72(6 Pt 1): 061601, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16485953

ABSTRACT

We present an x-ray reflectivity study of molecularly thin films of liquid isobutane adsorbed on liquid glycerol. The glycerol-isobutane interface serves as a model system to investigate the influence of the substrate adsorbate interactions on both adsorption isotherms and capillary wave fluctuations. The measured surface roughness is smaller than expected from the harmonic approximation of the interaction potential. Expressions for the surface roughness in slightly anharmonic potentials are given and compared to the experimental data. A good agreement between data and theory is achieved.

10.
Transplantation ; 65(12): 1584-90, 1998 Jun 27.
Article in English | MEDLINE | ID: mdl-9665074

ABSTRACT

BACKGROUND: In order to circumvent the complement-mediated hyperacute rejection of discordant xenografts, a colony of pigs transgenic for the human regulator of complement activity, human decay-accelerating factor (hDAF), has been produced. METHODS: Seven kidneys from hDAF transgenic pigs and six kidneys from nontransgenic control pigs were transplanted into cynomolgus monkeys; both native kidneys were removed during the same operation. The recipient animals were immunosuppressed with cyclosporine, steroids, and cyclophosphamide. RESULTS: In the transgenic group, the median survival time was 13 days (range, 6-35 days); the median survival time in the control group was 6.5 days (range, 0.3-30 days). There were no cases of hyperacute rejection in the transgenic group, and the two longest-surviving kidneys in this group showed no evidence of rejection on histological examination. In contrast, all control kidneys underwent antibody-mediated rejection, one demonstrating hyperacute rejection and the others acute vascular rejection. CONCLUSION: This study demonstrates that (i) a kidney from an hDAF transgenic pig can support the life of a primate for up to 35 days (and also shows the basic physiological compatibility between the pig and nonhuman primate); (ii) nontransgenic kidneys are not routinely hyperacutely rejected; and (iii) the presence of hDAF on the kidney confers some protection against acute vascular rejection. Improved immunosuppression and immunological monitoring may enable extended survival.


Subject(s)
CD55 Antigens/physiology , Graft Rejection/prevention & control , Kidney Transplantation/immunology , Transplantation, Heterologous/immunology , Animals , Animals, Genetically Modified , Antibody Formation , CD55 Antigens/genetics , Complement Hemolytic Activity Assay , Erythrocytes/immunology , Macaca fascicularis , Swine
11.
Transplantation ; 65(12): 1570-7, 1998 Jun 27.
Article in English | MEDLINE | ID: mdl-9665072

ABSTRACT

BACKGROUND: Previous studies demonstrated that hearts from transgenic pigs expressing human decay-accelerating factor (hDAF) were not hyperacutely rejected when transplanted heterotopically into the abdomen of cynomolgus monkeys. This study examines orthotopic transplantation of hDAF transgenic pig hearts into baboon recipients. METHODS: Orthotopic xenogeneic heart transplantation was performed using piglets, transgenic for hDAF, as donors. Ten baboons were used as recipients and were immunosuppressed with a combination of cyclophosphamide, cyclosporine, and steroids. RESULTS: Five grafts failed within 18 hr without any histological signs of hyperacute rejection. Pulmonary artery thrombosis induced by a size mismatch was observed in two of these animals. The other three recipients died because of failure to produce even a low cardiac output and/or dysrhythmia. The remaining five animals survived between four and nine days. One animal died of bronchopneumonia on day 4. Three xenografts stopped beating on day 5 due to acute vascular rejection. The longest survivor was killed on day 9 with a beating, histologically normal xenograft, because of pancytopenia. CONCLUSIONS: The results reported here demonstrate that hDAF transgenic pig hearts are not hyperacutely rejected when transplanted into baboon recipients. Orthotopically transplanted transgenic pig hearts are capable of maintaining cardiac output in baboons. An optimum immunosuppressive regimen is the subject of ongoing research.


Subject(s)
CD55 Antigens/physiology , Heart Transplantation , Animals , Animals, Genetically Modified , CD55 Antigens/genetics , Female , Graft Rejection , Immunosuppression Therapy , Male , Papio , Swine , Transplantation, Heterologous
12.
J Thorac Cardiovasc Surg ; 111(2): 367-78; discussion 378-80, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8583810

ABSTRACT

UNLABELLED: Because of experience gained in reconstructive mitral valve surgery, we have reevaluated the implantation of cryopreserved homografts in the mitral position. Forty-three patients, aged 11 to 69 years (mean 34 years), underwent mitral valve replacement with cryopreserved mitral homografts. The indications for the procedure were acute endocarditis (n = 14), rheumatic stenosis (n = 26), systemic lupus endocarditis (n = 2), and marasmic endocarditis (n = 1). All homografts were obtained from hearts explanted in the course of transplantation and were cryopreserved at -160 degrees C in 10% dimethyl sulfoxide solution without antibiotics. Appropriate sizing was based on morphologic study of the homografts and preoperative echocardiographic assessment of the recipient valve. In 82 homografts analyzed, the height of the anterior leaflet was 25 +/- 3 mm and the distance from the anulus to the apex of the anterior papillary muscle was 21 +/- 3 mm. The morphologic features of the papillary muscles were classified according to four types of increasing complexity. Nine valves with complex (type IV) papillary muscle abnormalities were discarded. Echocardiographic measurements of the valve were matched with those of the homograft identification cards and a slightly larger homograft was selected (measurements + 3 mm). Partial homograft replacement was done in case of a localized lesion (abscess or calcification) (n = 21). Total homograft replacement was undertaken in the presence of diffuse lesions (n = 22). Two hospital deaths occurred as a result of poor cardiac output. One patient required reoperation on the tenth postoperative day after a dehiscence on the valvular suture line. After a mean follow-up of 14 months, there has been one late death caused by a bronchial neoplasm and one reoperation for residual stenosis (partial replacement). The remaining patients were in either New York Heart Association class I (n = 25) or II (n = 13). Thirty-three patients were in sinus rhythm. Follow-up echocardiography has revealed no mitral regurgitation (n = 20), minimal mitral regurgitation (n = 13), and mild mitral regurgitation (n = 5). Surface valve area has been calculated at 2.5 +/- 0.4 cm2 in partial homograft reconstruction and 2.7 +/- 0.3 cm2 in total homograft replacement, with a transvalvular gradient of 3 +/- 4 mm Hg. CONCLUSION: In a selected group of patients, the use of mitral homografts significantly extended the present limitations of reparative surgery of the mitral valve.


Subject(s)
Endocarditis/surgery , Heart Valve Prosthesis , Mitral Valve Stenosis/surgery , Adolescent , Adult , Aged , Child , Humans , Middle Aged , Mitral Valve/surgery , Papillary Muscles
13.
J Thorac Cardiovasc Surg ; 113(3): 529-37, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9081098

ABSTRACT

The scarcity of small donors has significantly limited lung transplantation for pediatric and small adult patients. Use of single lobes procured from size-unmatched donors has overcome this difficulty, but only in a few selected cases and, in addition, it represents a waste of lung tissue. In an animal model we have shown that it is possible to divide one lung with careful partitioning of the vascular and bronchial structures and thus obtain two viable lobar grafts suitable for bilateral implantation in a smaller animal. We have now applied this procedure clinically in seven patients operated on between May 1993 and November 1994. The indications were cystic fibrosis in three children, primary pulmonary hypertension in two adults, bronchiectasis in one, and idiopathic pulmonary fibrosis in one. There were three children aged 13 to 17 years (median 14) and four adults aged 40 to 53 years (median 45). There was a 46% to 50% discrepancy for weight between recipient and donor and a 12% to 17% discrepancy for height. The surgical technique consisted of careful partitioning of the left donor lung, bilateral anterior thoracotomy in the recipient, and, with the use of cardiopulmonary bypass, implantation of the lower lobe in the left hemithorax and the upper lobe in the right hemithorax. Vascular and bronchial connections were facilitated by leaving a long pedicle on the recipient side. The pulmonary artery anastomosis for the donor left upper lobe was done with the "fissure" side of the artery to ensure an anastomosis without tension. An end-to-end bronchial anastomosis overcame the problem of size discrepancy. Six patients are alive and well 10 to 27 months (median 19) after operation. One patient with cystic fibrosis died of systemic aspergillosis infection. All were discharged from the hospital within the first or second postoperative month. No technical problems were identified: repeated bronchoscopy has demonstrated satisfactory healing without early stricture formation. All patients remain well subjectively with good exercise tolerance and all patients achieve greater than 70% of predicted values of forced expiratory volume in 1 second. Perfect adaptation of the transplanted lobes to the recipient pleural space has been demonstrated by postoperative computed tomographic scan. In conclusion, bilateral lobar transplantation from a single donor lung is possible in small adults or children when there is a large size discrepancy with the donor. This may help resolve the problem of donor availability in the pediatric population.


Subject(s)
Lung Diseases/surgery , Lung Transplantation/methods , Tissue Donors , Adolescent , Adult , Bronchiectasis/surgery , Cystic Fibrosis/surgery , Female , Humans , Hypertension, Pulmonary/surgery , Male , Middle Aged , Postoperative Care , Pulmonary Fibrosis/surgery , Treatment Outcome
14.
J Thorac Cardiovasc Surg ; 110(5): 1415-22; discussion 1422-3, 1995 Nov.
Article in English | MEDLINE | ID: mdl-7475193

ABSTRACT

Patients with cystic fibrosis who have end-stage respiratory failure and associated liver cirrhosis have been considered poor candidates for lung transplantation because of high morbidity and mortality resulting from hepatic insufficiency after the operation. Since April 1989, our policy has been to combine heart-lung or lung and liver transplantation in this group of patients. Between June 1990 and March 1995, among 25 patients accepted in the program for combined transplantation, nine died awaiting transplantation and 10 underwent one of the following procedures: heart-lung-liver transplantation (n = 5), en bloc double lung-liver transplantation (n = 1), sequential double lung-liver transplantation (n = 3), and bilateral lobar lung transplantation from a split left lung and reduced liver transplantation (n = 1). There were 5 male and 5 female patients. The ages of the recipients ranged from 10 to 24 years. Mean forced expiratory volume in 1 second was 29% and mean forced vital capacity was 35% of predicted values. All patients were infected with resistant Pseudomonas, three with Pseudomonas cepaceia, and two patients had Aspergillus species in addition. All patients had severe cirrhosis with portal hypertension. Four patients had a history of esophageal variceal bleeding and two had had previous portosystemic shunts. The operation was performed as a two-stage procedure, the intrathoracic operation being completed before the abdominal stage was begun. Cardiopulmonary bypass was used in all patients because of poor clinical condition. Immunosuppression consisted of azathioprine, cyclosporine, and prednisone, as for isolated lung transplantation. There were two perioperative deaths, one caused by primary liver failure and the second by early lung dysfunction. For the first 3 months after transplantation pulmonary infection was the most common cause of morbidity. Other complications included tracheal stenosis (n = 1), bronchial stenosis (n = 1), biliary stricture (n = 2), and severe ascites (n = 3). All were successfully treated. Obliterative bronchiolitis developed in three patients. This was stabilized with FK 506 in two patients; the other patient underwent retransplantation at 38 months but eventually died of bleeding. Actuarial survival was 70% at 1 year and remained unchanged at 3 years. Significant functional improvement was observed in all survivors. For patients who have chronic respiratory failure with advanced cirrhosis, lung transplantation combined with liver transplantation can be performed with a satisfactory outcome.


Subject(s)
Cystic Fibrosis/surgery , Liver Transplantation/methods , Lung Transplantation/methods , Adolescent , Adult , Aspergillosis/complications , Child , Female , Forced Expiratory Volume , Heart-Lung Transplantation , Humans , Immunosuppression Therapy/methods , Liver Cirrhosis/surgery , Lung Transplantation/mortality , Male , Postoperative Care , Postoperative Complications , Pseudomonas Infections/complications , Reoperation , Respiratory Insufficiency/surgery , Tissue Donors , Vital Capacity
15.
J Heart Lung Transplant ; 17(12): 1201-7, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9883761

ABSTRACT

BACKGROUND: The aim of this study was to investigate the effect of the expression of human decay-accelerating factor in transgenic pigs on hyperacute rejection in a pig-to-baboon heterotopic heart transplantation model and to assess the ability of such transgenic pig hearts in supporting the life of a primate when transplanted orthotopically. METHODS: Hearts from pigs transgenic for human decay-accelerating factor were transplanted heterotopically (n = 3) and orthotopically (n = 5) into the baboon. All animals received cyclosporine, steroids, and cyclophosphamide. Blood was sampled regularly for total antipig antibody titers, trough cyclosporine levels, full blood count, electrolytes, and creatinine. Rejection of the heterotopic hearts was defined as the absence of palpable cardiac pulsation. Explanted hearts were examined histologically with hematoxylin and eosin and with immunochemistry for complement components C3, C4, C9, and immunoglobulin M. RESULTS: None of the hearts were hyperacutely rejected. In the heterotopic group one heart underwent acute vascular rejection on day 13, and the remaining two recipients with beating xenografts were killed on days 2 and 21. In the orthotopic group, one recipient with a life-supporting xenograft was killed on day 9 because of poor general condition. Histologic examination demonstrated no evidence of rejection. Two xenografts stopped beating on day 5, and histologic study showed acute vascular rejection in both. There were also two graft failures for technical reasons in this group. CONCLUSIONS: Hyperacute rejection is abrogated in pig-to-baboon heart xenotransplantation with the expression of the human decay-accelerating factor transgene. The human decay-accelerating factor transgenic pig heart is able to support primate life for a prolonged period.


Subject(s)
Papio , Swine , Transplantation, Heterologous , Animals , Animals, Genetically Modified , CD55 Antigens/analysis , CD55 Antigens/genetics , Complement C9/analysis , Graft Rejection/immunology , Graft Rejection/pathology , Immunoglobulin M/analysis , Myocardium/immunology , Myocardium/pathology , Transplantation, Heterologous/immunology , Transplantation, Heterotopic
16.
J Clin Pathol ; 56(3): 237-9, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12610107

ABSTRACT

This report describes a rare case of chronic osteomyelitis in a 60 year old man mimicking a soft tissue sarcoma. Chronic osteomyelitis is an infrequent cause of a soft tissue mass and is usually diagnosed clinically by a combination of radiology and microbiology. Rarely, COM can mimic a primary bony neoplasm, but this is the first reported case where it mimicked a soft tissue sarcoma. The clinical, radiological, and histological appearances of this case will be discussed.


Subject(s)
Osteomyelitis/diagnosis , Sarcoma/diagnosis , Soft Tissue Neoplasms/diagnosis , Chronic Disease , Diagnosis, Differential , Humans , Leiomyoma/diagnosis , Male , Middle Aged , Ribs
17.
Ann Thorac Surg ; 64(4): 1072-4, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9354530

ABSTRACT

BACKGROUND: Interposition grafting or patch repair of adult coarctations of the aorta are the standard methods of surgical treatment. Both involve use of prosthetic material, and patch repair using prosthetic material may lead to aneurysm formation in the long term. METHODS: Four patients aged 17 to 29 years had been investigated for systemic hypertension and had coarctation of the aorta diagnosed on cardiac catheterization. Between March and November 1984, all 4 underwent a corrective operation. The lesions were widely incised and a broad patch of ipsilateral mammary or Abbott's artery was fashioned across the narrowing. The arteries had been enlarged in diameter because of prolonged exposure to high blood pressure as collateral vessels, although none was intrinsically diseased. RESULTS: After 12 years of follow-up, only 1 patient remains on antihypertensive therapy. Spiral computed tomographic reconstructions revealed only very mild residual stenosis in 1 patient, confirmed by subsequent aortography. CONCLUSIONS: In adult patients with coarctation of the aorta, the use of the enlarged internal mammary artery as a patch graft is a simple, quick procedure, which may give lasting relief of obstruction. Spiral computed tomographic scanning is an ideal noninvasive method of follow-up.


Subject(s)
Aortic Coarctation/surgery , Mammary Arteries/transplantation , Adolescent , Adult , Aortography , Arteries/transplantation , Follow-Up Studies , Humans , Image Processing, Computer-Assisted
18.
Ann Thorac Surg ; 72(3): 933-5, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11565693

ABSTRACT

Since the inception of lung transplantation in 1982, it has been standard practice to implant donor lungs on the ipsilateral side in the recipient. The development of the techniques of lobar and bilateral lobar transplantation has shown that lung morphology may adapt to the shape of the thorax. Thus, variations in implantation have become possible. We describe a case of a 30-year-old man with severe bronchiectasis due to ciliary dyskinesis which required a left lower lobectomy at the age of 11 years and a left completion pneumonectomy 10 years later. His disease progressed and he was listed for a right lung transplantation. At the time of transplantation, the donor right lung was noted to be edematous and unfit for transplantation. This required grafting the donor left lung in the right thorax of the recipient. Follow-up at 7 years shows good exercise capacity and excellent functional tests without evidence of rejection.


Subject(s)
Bronchiectasis/surgery , Lung Transplantation/methods , Transplantation, Heterotopic/methods , Adult , Bronchiectasis/etiology , Ciliary Motility Disorders/complications , Humans , Male
19.
Ann Thorac Surg ; 55(1): 86-8, 1993 Jan.
Article in English | MEDLINE | ID: mdl-8417716

ABSTRACT

A prospective, controlled, randomized study of 80 patients undergoing esophageal operations was undertaken, in which one group of patients was given digoxin and the other was not. The incidence of cardiac dysrhythmia was compared in each group. Twenty-six patients underwent operation for benign disease. Equal numbers were digitalized or not and no dysrhythmias occurred. Fifty-four patients underwent operation for malignant disease. Of 26 in the group digitalized, 12 suffered dysrhythmia (46%). Of 28 not digitalized, 9 suffered dysrhythmia (32%). Overall, 39% of patients with malignant disease suffered a dysrhythmia compared with none with benign disease (p < 0.002 by chi 2).


Subject(s)
Arrhythmias, Cardiac/prevention & control , Digoxin/administration & dosage , Esophageal Diseases/surgery , Esophageal Neoplasms/surgery , Intraoperative Complications/prevention & control , Postoperative Complications/prevention & control , Premedication , Aged , Arrhythmias, Cardiac/mortality , Electrocardiography/drug effects , Esophageal Diseases/mortality , Esophageal Neoplasms/mortality , Female , Humans , Intraoperative Complications/mortality , Male , Postoperative Complications/mortality , Thoracotomy
20.
Ann Thorac Surg ; 63(2): 465-9, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9033321

ABSTRACT

BACKGROUND: Conservative surgical options in the treatment of congenital aortic stenosis are limited. To relieve the obstruction necessitates full incision of the raphe of the larger valve leaflet, but this inevitably causes prolapse. METHODS: We performed aortic valve repair in 6 children, aged 14 months to 17 years, with congenital aortic stenosis, 2 having had aortic valvotomy as infants. The repair consisted of suturing the base of a triangular piece of bovine pericardium, with a simple vertical fold, to the free edges of the incised raphe. The pericardial fold was then sutured vertically to the aortic wall. RESULTS: At follow-up of 2 to 60 months, the mean peak systolic Doppler gradients had decreased from 80 +/- 15 mm Hg to 26 +/- 9 mm Hg. The effective valvular orifice area increased from 33% +/- 6% to 64% +/- 3%, allowing blood flow to increase by a factor of 3.76. Two patients have mild and 2 have mild-to-moderate aortic regurgitation. CONCLUSIONS: The described conservative repair renders the valve tricuspid and trisinusoidal, and the deficient interleaflet triangle is recreated, preventing cusp prolapse. Longer follow-up is required to assess the durability of unstented pericardium in the aortic position, but the early results are encouraging.


Subject(s)
Aortic Valve Stenosis/surgery , Pericardium/transplantation , Adolescent , Animals , Aortic Valve Stenosis/congenital , Aortic Valve Stenosis/diagnostic imaging , Cattle , Child , Child, Preschool , Echocardiography, Doppler , Humans , Infant , Treatment Outcome
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