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Shahid Husain Kenneth McCurry James Dauber Nina Singh Shimon Kusne 《The Journal of heart and lung transplantation》2002,21(3):354-359
BACKGROUND: Nocardia is responsible for infection in both normal and immunocompromised hosts. Organ transplant recipients are increasingly recognized as a sub-group of immunocompromised patients in whom nocardia is an important pathogen. The frequency of nocardia in organ transplant recipients varies between 0.7% and 3%. Nocardia infection has largely been reported in heart, kidney and liver transplant recipients. Presentations of nocardia in lung transplant recipients have been restricted primarily to case reports. The present study reviews the clinical and epidemiologic characteristics of nocardia infection in lung transplant recipients at our institution. METHODS: A retrospective cohort study of 473 lung transplant recipients from January 1991 to November 2000 was done at a university hospital. Patient demographics, immunosuppressive regimen at the time of isolation of nocardia species, use of trimethoprim-sulfamethoxazole for Pneumocystis carinii prophylaxis, rejection episodes in the preceding 6 months, concurrent pathogens, site of infection, radiologic findings and treatment and outcome were recorded. RESULTS: Nocardia infection was found in 2.1% (10 of 473) of our lung transplant recipients. Median time of onset was 34.1 months after transplantation. Nocardia species included N farcinica in 30% (3 of 10), N nova in 30% (3 of 10), N asteroides complex in 30% (3 of 10) and N brasiliensis in 10% (1 of 10) of patients. Post-transplant diabetes was present in 50% (5 of 10) of patients. The primary indication for lung transplantation was emphysema in 40% (4 of 10). Native lung involvement was noted in 75% (3 of 4) of patients with single lung transplant. Breakthrough nocardia infection were noted in 6 patients who were receiving trimethoprim-sulfamethoxazole prophylaxis for P carinii pneumonia; all breakthrough isolates remained susceptible to trimethoprim-sulfamethoxazole. Overall mortality was 40% (4 of 10). All patients (3 of 3) with infection due to N farcinica, except 1 (1 of 7) with infection due to other nocardia species, died. Seventy-five percent (3 of 4) of deaths were attributable to nocardia infection. CONCLUSIONS: Nocardia infection tended to involve the native lung in single lung transplant recipients. Trimethoprim-sulfamethoxazole for P carinii prophylaxis at the doses given was not protective against nocardiosis in these patients. Infection with N farcinica was associated with poor outcome. Thus, species identification and extended courses of antibiotics based on antimicrobial susceptibility testing are important in management of these patients. 相似文献
3.
4.
Abdul Rahman Arishi M. Ezzedien Rabie M. Shahid Hussain Khan Hassan Sumaili Hassan Shaabi Nabil Tadros Michael Bheem Sing Shekhawat 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2008,12(3):321-325
Spillage of gallstones may occur in the course of laparoscopic cholecystectomy. The incidence of this mishap and its consequences are variable. Ignored by many surgeons, stone spillage may be the source of significant morbidity many years after surgery. In this report, we describe the clinical course of a patient who presented with upper abdominal pain and swelling. The past history was positive for laparoscopic cholecystectomy 15 years earlier. After excision, the swelling was found to be a pseudocyst formed around spilled gallstones during a previous cholecystectomy. Apart from postoperative wound infection, the patient recovered well and remains so. Here, we discuss the problem and provide suggestions for spillage prevention and stone retrieval once spillage occurs. 相似文献
5.
Species-dependent differences in the properties of particulate cyclic nucleotide phosphodiesterase from rat and rabbit ventricular myocardium 总被引:3,自引:0,他引:3
M Shahid M Wilson C D Nicholson R J Marshall 《The Journal of pharmacy and pharmacology》1990,42(4):283-284
The ability of cyclic nucleotide phosphodiesterases (PDEs) to hydrolyse cyclic (c)AMP in rat and rabbit ventricular myocardium has been compared. The PDE activity of rabbit, but not rat, cardiac homogenate and supernatant fraction was potentiated by Ca2+/calmodulin and attenuated by cGMP. Both rabbit and rat ventricular myocardium were shown to have a membrane bound PDE. However, rabbit membrane-bound PDE was inhibited by cGMP and low concentrations of milrinone (IC50 2.7 microM). In contrast, rat membrane-bound PDE was not inhibited by either cGMP or low concentrations of milrinone (IC50 19 microM), but it was potently inhibited by rolipram (IC50 2.2 microM). Thus, in rabbit the particulate PDE is milrinone sensitive (PDE III) whilst in rat it is the rolipram sensitive (PDE IV) isoenzyme. There are clearly species differences in the intracellular localization and relative activities of PDE isoenzymes in cardiac tissue. This may explain the species differences already found in the activity of selective PDE isoenzyme inhibitors as inotropic agents. 相似文献
6.
Shahid Hussain Darren E Dreyfus Richard J Marcus Robert W W Biederman Rita L McGill 《Nephrology, dialysis, transplantation》2003,18(11):2364-2368
BACKGROUND: Spironolactone is useful in heart failure, but is not given to dialysis patients for fear of hyperkalaemia. This study evaluated the safety of spironolactone administration in haemodialysis patients. METHODS: Fifteen haemodialysis outpatients with mean serum potassium <5.6 mEq/l over the preceding 4 months were treated with spironolactone 25 mg daily for 28 days. Serum potassium was measured before every haemodialysis during the study. Aldosterone and renin were measured at the beginning and end of the study. Patients were monitored for side effects. Data were examined with a paired t-test, with patients serving as their own controls and P < 0.05 considered significant. A sample size of 14 was required to achieve a power of 0.8 and a P = 0.05 to detect a potassium difference of 0.5 +/- 0.6 mEq/l. All patients were analysed as intention-to-treat. RESULTS: The mean potassium level was 4.6 +/- 0.6 mEq/l at baseline and 4.9 +/- 0.9 mEq/l at study completion (P = 0.14). Thirteen patients completed the trial with no potassium levels >6.0 mEq/l. Four patients had potassium levels between 5.5 and 6.0 mEq/l. One patient was withdrawn at day 20 after developing hyperkalaemia (7.6 mEq/l). Another patient was withdrawn at day 25 after missing a dialysis treatment. There were no differences in either baseline or 28 day aldosterone or renin levels (16.8 +/- 28.8 vs 11.7 +/- 6.1 ng/dl and 3.5 +/- 3.9 vs 3.5 +/- 3.5 ng/ml/h, respectively). Infrequent side effects included dry mouth, nosebleed, pruritis, gynecomastia and diarrhoea. No significant leukopenia or anaemia was noted. CONCLUSIONS: Spironolactone may be considered as a treatment option for selected chronic haemodialysis patients with heart disease. 相似文献
7.
Telfer JF; Thomson AJ; Cameron IT; Greer IA; Norman JE 《Human reproduction (Oxford, England)》1997,12(10):2306-2312
Superoxide, an agent which attenuates the half-life of nitric oxide, is
metabolized and synthesized by superoxide dismutase (SOD) and xanthine
oxidase, respectively. Over the last few years much work has focused on the
role of nitric oxide in human parturition. The aim of this study was to
determine whether the onset of human parturition is associated with a
change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD),
manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the
uterus. Samples of myometrium, placenta, decidua and fetal membranes were
obtained from women before and after the onset of labour at term.
Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine
oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like
immunoreactivity was detected in syncytiotrophoblast cells, villous stromal
cells and endothelial cells of blood vessels in the placenta. In the
myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial
cells and to some vascular smooth muscle cells. In the fetal membranes we
observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion,
extravillous trophoblast and decidua. There was no difference in SOD enzyme
activity or staining intensity for SOD between different cell types before
and during labour. Xanthine oxidase immunoreactivity was identified in each
of the tissues examined and again there was no difference in immunostaining
in tissues obtained from women delivered before or after the onset of
labour. These results show that the pregnant uterus is capable of both
synthesizing and degrading superoxide and suggest that superoxide dismutase
and xanthine oxidase may play a role in the maintenance of uterine
quiescence during pregnancy, but not in the initiation of parturition.
相似文献
8.
A C-Terminal Hydrophobic Region is Required for Homo-Oligomerization of the Hepatitis E Virus Capsid (ORF2) Protein 总被引:1,自引:0,他引:1 下载免费PDF全文
Hepatitis E virus (HEV) is the causative agent of hepatitis E, anacute form of viral hepatitis. The open reading frame 2 (ORF2) of HEV encodes the viral capsid protein, which can self-oligomerize into virus-like particles. To understand the domains within this protein important for capsid biogenesis, we have carried out in vitro analyses of association and folding patterns of wild type and mutant ORF2 proteins. When expressed in vitro or in transfected cells, the ORF2protein assembled as dimers, trimers and higher order forms. WhileN-terminal deletions up to 111 amino acids had no effect, the deletion of amino acids 585–610 led to reduced homo-oligomerization. This deletion also resulted in aberrant folding of the protein, as determined by its sensitivity to trypsin. This study suggests that a C-terminal hydrophobic region encompassing amino acids 585–610 of the ORF2 protein might be critical for capsid biogenesis. 相似文献
9.
Endothelin receptor expression in human decidua 总被引:3,自引:1,他引:3
Kohnen G; Campbell S; Irvine GA; Church HJ; MacLachlan F; Titterington M; Cameron IT 《Molecular human reproduction》1998,4(2):185-193
The endothelins are signalling peptides that act via two receptors, ET(A)
and ET(B). In the human endometrium, endothelin receptors have been
demonstrated in glands and stroma and have been shown to vary during the
course of the menstrual cycle. The present study was undertaken to
determine whether or not expression of endothelin receptors changes during
pregnancy or after administration of exogenous progestagens. The expression
of the receptors was correlated with the appearance of basement membrane
components during decidualization of the endometrial stroma. Decidual
specimens (n = 15) were obtained during the first trimester of pregnancy
and 10 at term. Sixteen pairs of endometrial biopsies were obtained from
women with menorrhagia before and after exposure to exogenous progestagens.
A total of 15 hysterectomy specimens were used as controls for the
expression of stromal basement membrane proteins in the absence of
decidualization. Autoradiography was carried out with selective ligands for
ET(A) ([125I]-PD 151242) and ET(B) ([125I]-BQ3020). The distribution of
ligand binding was then compared with the distribution of laminin alpha2
light chain and collagen IV. ET(A), ET(B), laminin alpha2 light chain, and
collagen IV were expressed in stromal decidual cells in the first trimester
of pregnancy. ET(B) was also found on endometrial glandular epithelium.
Quantitative macro-autoradiography and multiple regression analysis
demonstrated a highly significant positive correlation (P < 0.001)
between expression of ET(B) and laminin alpha2 light chain. In the third
trimester qualitative examination suggested a reduction of ET(A) in the
stroma. Progestagen-induced decidua exhibited a similar pattern to that
found in first trimester decidua. This study has demonstrated up-regulation
of ET(B) during the progesterone- dependent process of decidualization and
suggests a paracrine or autocrine role for endothelins in the decidua.
相似文献
10.
H M Dockrell S K Young K Britton P J Brennan B Rivoire M F Waters S B Lucas F Shahid M Dojki T J Chiang Q Ehsan K P McAdam R Hussain 《Infection and immunity》1996,64(10):4385-4389
Twelve mycobacterial antigens were compared for induction of gamma interferon (IFN-gamma) secretion by human blood mononuclear cells of patients with leprosy. Fractionated Mycobacterium leprae antigens containing cell wall proteins or cytosolic and membrane proteins induced good IFN-gamma responses in tuberculoid leprosy patients. Lipoarabinomannan from M. tuberculosis Erdman and M. leprae mycolylarabinogalactan peptidoglycan were the poorest IFN-gamma inducers. 相似文献