Search PubMed⌕ Search

Biomedical subjects

R Ullrich

Publications and source records attributed to R Ullrich.

At least 19 recordsLinked to original sources

F-wave amplitudes indicate evolving spinal autonomy during spontaneous recovery of hindlimb function in rat spinal cord contusion.

STUDY DESIGN: Experimental rat model of spinal cord contusion. OBJECTIVES: To reveal the extent of spinal autonomy contributing to recovery of hindlimb function. SETTING: Experimental laboratory of a neurosurgical university department. METHODS: F-wave amplitudes as a probe for spinal cord excitability were recorded from both sciatic nerves (lumbar segments L2-L5) before and after an experimental spinal cord contusion performed in the lower thoracic spinal cord. Additionally, transcranial electrically motor evoked potentials from the hindlimbs and cerebral somatosensory potentials evoked by sciatic nerve stimulation were recorded. Clinical evaluation of hindlimb function was done regularly for survival periods of 3 and 50 days, respectively. Electrophysiological testing was performed immediately prior and after lesioning of the cord and at the endpoint of survival periods. RESULTS: Hindlimb function recovered from a mean Basso-Beattie-Bresnahan score of 5.6 on day 1 to 9.2 on day 3 (3-day-survivors) and from 7.7 to 17.2 on day 50 (50-day-survivors). This was accompanied by a significant increase of F-wave amplitudes on day 50 compared to baseline values, whereas amplitudes of somatosensory and motor-evoked potentials remained significantly depressed. CONCLUSION: Recovery of hindlimb function may at least in part be attributed to evolving spinal autonomy, which can be assessed by F-wave amplitudes.

Action Potentials↗

Recovery from giant cell myocarditis with ECMO support and utilisation of polyclonal antithymocyte globulin: a case report.

Giant cell myocarditis (GCM) is a rare and frequently fatal disorder. Patients suffer of ventricular arrhythmias or congestive heart failure. Here we describe a patient with cardiogenic shock and histological verified GCM. The patient was saved by implantation of extracorporeal membrane oxygeneation (ECMO) device and concomitant application of Rabbit antithymocyte globuline (rATG, Thymoglobulin, Sangstat), cyclosporine, and steroids in the acute event. 12 months after the crisis the patient evidences NYHA class I heart function and only a moderate impairment of heart function (EF 55%). The novel utilisation of ECMO in GCM related cardiogenic shock and application of rATG have prooven life-saving in this patient. Studies utilizing rATG in the treatment of GCM are warrented.

Antilymphocyte Serum↗

Evidence for complex multigenic inheritance of radiation AML susceptibility in mice revealed using a surrogate phenotypic assay.

The mapping of genes which affect individual cancer risk is an important but complex challenge. A surrogate assay of susceptibility to radiation-induced acute myeloid leukaemia (AML) in the mouse based on chromosomal radiosensitivity has been developed and validated. This assay was applied to the mapping of radiation-induced AML risk modifier loci by association with microsatellite markers. A region on chromosome (chr) 18 with strong association is identified and confirmed by backcross analysis. Additional loci on chrs 8 and 13 show significant association. A key candidate gene Rbbp8 on chr18 is identified. Rbbp8 is shown to be upregulated in response to X-irradiation in the AML sensitive CBA strain but not AML resistant C57BL/6 strain. This study demonstrates the strength of utilizing surrogate endpoints of cancer susceptibility in the mapping of mouse loci and identifies additional loci that may affect radiation cancer risk.

Acute Disease↗

Mineralization of 14C-labelled synthetic lignin and extracellular enzyme activities of the wood-colonizing ascomycetes Xylaria hypoxylon and Xylaria polymorpha.

Two wood-dwelling ascomycetes, Xylaria hypoxylon and Xylaria polymorpha, were isolated from rotting beech wood. Lignin degradation was studied following the mineralization of a synthetic [formula: see text]-labelled lignin in solid and liquid media. Approximately 9% of the synthetic lignin was mineralized by X. polymorpha during the growth on beech wood meal, and the major fraction (65.5%) was polymerized into water- and dioxan-insoluble material. Both fungi produced laccase (up to 1,200 U l-1) in an agitated complex medium based on tomato juice; peroxidase activity (<80 U l-1) was only detected for X. polymorpha in soybean meal suspension. The enzymatic attack of X. polymorpha on beech wood resulted in the formation of three fractions of water-soluble lignocellulose fragments with molecular masses of 200, 30 (major fraction) and 3 kDa, as demonstrated by high-performance size exclusion chromatography. This fragment pattern differs considerably from that of the white-rot fungus Bjerkandera adusta, which preferentially released smaller lignocellulose fragments (0.8 kDa). The finding that X. polymorpha produced large lignocellulose fragments, along with the fact that high levels of hydrolytic enzymes (esterase 630 U l-1, xylanase 120 U l-1) were detected, indicates the cleavage of bonds between the lignin and hemicellulose moieties.

Biopolymers↗

Stimulatory effects of distinct members of the bone morphogenetic protein family on ligament fibroblasts.

OBJECTIVE: To investigate effects of cartilage derived morphogenetic protein-1 and -2 (CDMP-1, CDMP-2), bone morphogenetic protein (BMP)-7 and BMP-6 on metabolism of ligament fibroblasts and their osteogenic or chondrogenic differentiation potential. METHODS: Ligament fibroblasts were obtained from 3 month old calves, plated as monolayers or micromass cultures, and incubated with or without CDMP-1, CDMP-2, BMP-7, and BMP-6. Expression of the indicated growth factors was assessed by RT-PCR and western immunoblotting. The presence of their respective type I and II receptors, and lineage related markers, was investigated in stimulated and unstimulated cells by RT-PCR and northern blotting. Biosynthesis of matrix proteoglycans was assessed by [(35)S]sulphate incorporation in monolayers. Alcian blue and toluidine blue staining was done in micromass cultures. RESULTS: CDMP-1, CDMP-2, BMP-7, and BMP-6 were detected on mRNA and on the protein level. Type I and II receptors were endogenously expressed in unstimulated ligament fibroblasts. The growth factors significantly stimulated total proteoglycan synthesis as assessed by [(35)S]sulphate incorporation. Toluidine blue staining showed cartilage-specific metachromasia in the growth factor treated micromass cultures. Transcription analysis of stimulated ligament fibroblasts demonstrated coexpression of chondrocyte markers but no up regulation of osteogenic markers. CONCLUSION: CDMP-1, CDMP-2, BMP-7, and BMP-6 and their receptors were expressed in ligament tissue. These growth factors induced matrix synthesis in fibroblasts derived from bovine ligament. The preferential expression of cartilage markers in vitro suggests that CDMP-1, CDMP-2, BMP-7, and BMP-6 have the potential to induce differentiation towards a chondrogenic phenotype in ligament fibroblasts. Thus, fibroblasts from ligaments may serve as a source for chondrogenesis and tissue repair.

Animals↗

Early failure of the tissue engineered porcine heart valve SYNERGRAFT in pediatric patients.

OBJECTIVES: The first tissue engineered decellularized porcine heart valve, Synergraft (Cryolife Inc., USA) was introduced in Europe as an alternative to conventional biological valves. This is the first report of the rapid failure of these new grafts in a small series. MATERIALS AND METHODS: In 2001, 2 model 500 and 2 model 700 Synergraft valves were implanted in four male children (age 2.5-11 years) in the right ventricular outflow tract as a root. Two patients had a Ross operation and two had a homograft replacement. RESULTS: The cryopreserved Synergraft valves appeared macroscopically unremarkable at implantation. Recovery from surgery was uneventful and good valve function was demonstrated postoperatively. Three children died, two suddenly with severely degenerated Synergraft valves 6 weeks and 1 year after implantation. The third child died on the 7th day due to Synergraft rupture. Subsequently the fourth graft was explanted prophylactically 2 days after implantation. Macroscopically all four grafts showed severe inflammation starting on the outside (day 2 explant) leading to structural failure (day 7 explant) and severe degeneration of the leaflets and wall (6 weeks and 1 year explant). Histology demonstrated severe foreign body type reaction dominated by neutrophil granulocytes and macrophages in the early explants and a lymphocytic reaction at 1 year. In addition significant calcific deposits were demonstrated at all stages. Surprisingly pre-implant samples of the Synergraft revealed incomplete decellularization and calcific deposits. No cell repopulation of the porcine matrix occurred. CONCLUSION: The xenogenic collagen matrix of the Synergraft valve elicits a strong inflammatory response in humans which is non-specific early on and is followed by a lymphocyte response. Structural failure or rapid degeneration of the graft occurred within 1 year. Calcific deposits before implantation and incomplete decellularization may indicate manufacturing problems. The porcine Synergraft treated heart valves should not be implanted at this stage and has been stopped.

Animals↗

Rapamycin as rescue therapy in a patient supported by biventricular assist device to heart transplantation with consecutive ongoing rejection.

Rapamycin is a new immunosuppressive agent that has been shown to be effective in acute heart allograft rejection. This case documents a patient suffering from cardiac sarcoidosis who was bridged to transplantation for 90 days with ongoing rejection after allograft implantation. Rejection did not abate despite treatment with antithymocyte globulin (ATG), FK506, a mycophenolate switch and courses of multiple apheresis. Initiation of rapamycin treatment resulted in a rapid resolution of cardiac rejection and reduction of concomitant immunosuppressive agents with few side-effects. Most notably was the reduction of panel reactive antibodies within a few weeks after the rapamycin initiation. This case illustrates that the utilization of rapamycin ceased ongoing rejection in a patient with a clear hyperimmune state despite prior extensive utilization of a variety of immunosuppressive strategies after heart transplantation.

Adult↗

Impact of overall treatment time on local control of anal cancer treated with radiochemotherapy.

Between 1987 and 2000, 111 patients with epidermoid anal cancer (T1-T4 Nx M0) were assigned to primary simultaneous radiochemotherapy (RCT) with a radiation dose of 45 Gy, performed either as a split course with 2-Gy single fractions (schedule A, 1987-1996, n = 65 patients) or continuously with fractions of 1.8 Gy (schedule B, 1996-2000; n = 38 patients). The chemotherapy consisted of continuous infusions of 5-fluorouracil (5-FU; 800/1,000 mg/m(2)/day, on 4/5 consecutive days, during weeks 1 and 5) together with one (schedule A) or two (schedule B) short infusions of mitomycin C (10 mg/m(2)) during the first course of 5-FU. Associations between clinical outcome and various prognostic factors were assessed in 103 patients who completed these schedules. For both patient groups combined, 5-year local control rate was 67% and 5-year survival rate 71%. Advanced tumor stage, size, and nodal status significantly decreased the 5-year local control rate as well as the overall treatment time (OTT) >41 days (58% for OTT >41 days vs. 79% for OTT < or =41 days; p = 0.04). However, we did not find a correlation with the prescribed radiotherapy schedule (A or B). In conclusion, in patients with anal carcinomas treated with RCT with a radiation dose of 45 Gy, the predominant determinant of local control is the resulting OTT and not the administration schedule (split course or continuous radiotherapy).

Adult↗

Giant benign cystic mesothelioma: a case report and review of literature.

A 28-year-old man was admitted because of weight loss and a huge abdominal mass. The abdominal cavity was filled by a large number of cysts with a maximum diameter of 10 cm as diagnosed by ultrasound and computed tomography. Laparotomy was performed and a 33 kg cystic tumour originating from the peritoneum was resected en bloc. Histopathological work-up showed multiple cysts covered by cubic or flat mesothelial cells with uniform nuclei. The final diagnosis was benign cystic mesothelioma. Twenty-three months after surgical debulking, a follow-up computed tomography scan showed recurrence of the disease. In this report, we describe the characteristics, aetiology and differential diagnosis of this rare lesion.

Adult↗

Increased intimal apoptosis in coronary atherosclerotic vessel segments lacking compensatory enlargement.

OBJECTIVES: In a histopathologic study, we assessed the balance of cell proliferation and apoptosis by counting the number of apoptotic and proliferating cell nuclear antigen-positive cells in freshly harvested atherectomy specimens from 34 patients. BACKGROUND: Remodeling of human coronary arteries is an adaptive process that alters vascular lumen size. METHODS: Intravascular ultrasound was performed prior to atherectomy. Total vessel area (area within the external elastic lamina [EEL]), lumen area and plaque area were measured at the region of interest (ROI), and at a proximal and distal reference segment, utilizing the formula Delta(%)=100x(ROI-reference segment)/reference segment. Positive arterial remodeling (R+) resulting in luminal expansion was defined as DeltaEEL >10%. Absence of remodeling (0 < DeltaEEL <10%) and constrictive arterial remodeling (DeltaEEL <0) were considered as neutral remodeling (R0) and negative remodeling (R-), respectively. RESULTS: In R- lesions, apoptotic indices (APO) were significantly elevated (17.17 +/- 2.19%) compared with R+ lesions (4.89 +/- 1.7%; p = 0.0007). In a rabbit iliac percutaneous transluminal coronary angioplasty model intimal apoptosis was increased four weeks after balloon angioplasty injury (APO 8.8 +/- 0.03%) compared with contralateral untreated segments (APO 3.0 +/- 0.04%, n = 6). Lesions with an EEL/intimal area <3.0 showed significantly more intimal apoptosis than untreated lesions (p = 0.02). CONCLUSIONS: The data indicate that constrictive remodeling of atherosclerotic coronary lesions is associated with increased apoptosis of intimal cells. We speculate that increased apoptosis is due to extensive plaque healing after episodes of symptomatic or asymptomatic plaque rupture.

Adaptation, Physiological↗

Endothelial nitric oxide synthase limits left ventricular remodeling after myocardial infarction in mice.

Background- To investigate the role of endothelial nitric oxide synthase (NOS3) in left ventricular (LV) remodeling after myocardial infarction (MI), the impact of left anterior descending coronary artery ligation on LV size and function was compared in 2- to 4-month-old wild-type (WT) and NOS3-deficient mice (NOS3(-/-)). Methods and Results- Two days after MI, both strains of mice had a similar LV size, fractional shortening, and ejection fraction by echocardiography. Twenty-eight days after MI, both strains had dilated LVs with decreased fractional shortening and lower ejection fractions. Although the infarcted fraction of the LV was similar in both strains, LV end-diastolic internal diameter, end-diastolic volume, and mass were greater, but fractional shortening, ejection fraction, and the maximum rate of developed LV pressure (dP/dt(max)) were lower in NOS3(-/-) than in WT mice. Impairment of diastolic function, as measured by the time constant of isovolumic relaxation (tau) and the maximum rate of LV pressure decay (dP/dt(min)), was more marked in NOS3(-/-) than in WT mice. Mortality after MI was greater in NOS3(-/-) than in WT mice. Long-term administration of hydralazine normalized blood pressure in NOS3(-/-) mice, but it did not prevent the LV dilatation, impaired systolic and diastolic function, and increased LV mass that followed MI. In WT mice, capillary density and myocyte width in the nonischemic portion of the LV did not differ before and 28 days after MI, whereas in NOS3(-/-) mice, capillary density decreased and myocyte width increased after MI, whether or not hydralazine was administered. Conclusions- These results suggest that the presence of NOS3 limits LV dysfunction and remodeling in a murine model of MI by an afterload-independent mechanism, in part by decreasing myocyte hypertrophy in the remote myocardium.

Animals↗

Attenuation of hypoxic pulmonary vasoconstriction by endotoxemia requires 5-lipoxygenase in mice.

Sepsis and endotoxemia impair hypoxic pulmonary vasoconstriction (HPV), thereby reducing systemic oxygenation. To assess the role of leukotrienes (LTs) in the attenuation of HPV during endotoxemia, the increase in left lung pulmonary vascular resistance (LPVR) before and during left mainstem bronchus occlusion (LMBO) was measured in mice with and without a deletion of the gene encoding 5-lipoxygenase (5-LO). LMBO increased the LPVR equally in saline-challenged wild-type and 5-LO-deficient mice (96+/-20% and 94+/-19%, respectively). Twenty-two hours after challenge with Escherichia coli endotoxin, the ability of LMBO to increase LPVR was markedly impaired in wild-type mice (27+/-7%; P<0.05) but not in 5-LO-deficient mice (72+/-9%) or in wild-type mice pretreated with MK886, an inhibitor of 5-LO activity (76+/-10%). Compared with wild-type mice, endotoxin-induced disruption of lung structures and inflammatory cell influx in the lung were markedly attenuated in 5-LO-deficient mice. Administration of MK571, a selective cysteinyl LT(1) receptor antagonist, 1 hour before endotoxin challenge preserved HPV and attenuated pulmonary injury in wild-type mice but did not prevent the endotoxin-induced increase in pulmonary myeloperoxidase activity. Taken together, these findings demonstrate that a 5-LO product, most likely a cysteinyl LT, contributes to the attenuation of HPV and to pulmonary injury after challenge with endotoxin.

Administration, Inhalation↗

Rapid increase of mucosal CD4 T cells followed by clearance of intestinal cryptosporidiosis in an AIDS patient receiving highly active antiretroviral therapy.

Highly active antiretroviral therapy (HAART) suppresses the replication of human immunodeficiency virus (HIV) and leads to an increase in circulating CD4 T lymphocytes, but its effects on other immune compartments such as the intestinal mucosa are not well understood. We describe a severely immunodeficient HIV-infected patient with intractable watery diarrhea and weight loss caused by infection with Cryptosporidium parvum in whom we studied virologic and immunologic changes in both peripheral blood and the intestinal mucosa after initiating HAART. Mucosal biopsies were performed by rectoscopy before and at several time points after HAART was begun. Nucleic acids were extracted from rectal biopsy specimens and blood samples, and HIV RNA was measured by reverse-transcription polymerase chain reaction. Lymphocytes were isolated from rectal biopsy specimens after mechanical disaggregation, and circulating and mucosal CD4 T cells were determined by flow cytometry. HAART led to clinical recovery and eradication of cryptosporidiosis. In both blood and mucosa, HIV RNA decreased below the limit of detection and CD4 T cells increased. Mucosal CD4 T cells increased much faster and to much higher levels than circulating CD4 T cells. Our findings show a rapid repopulation of the intestinal mucosa with CD4 T cells after initiation of HAART that can effectively restore mucosal immunity, leading to eradication of opportunistic pathogens.

Acquired Immunodeficiency Syndrome↗

Celiac disease-like abnormalities in a subgroup of patients with irritable bowel syndrome.

BACKGROUND & AIMS: Abdominal symptoms in the absence of mucosal abnormalities are features of both the irritable bowel syndrome (IBS) and latent/potential celiac disease (cd). To identify a possible subgroup of IBS patients with latent/potential cd, surrogate markers of cd were investigated in IBS patients. METHODS: IBS patients suffering from diarrhea (n = 102), and patients with active cd (n = 10), treated cd (n = 26), and latent cd (n = 5) were included in the study. We measured serum immunoglobulin (Ig) A against gliadin and tissue-transglutaminase, and IgA and IgM against gliadin, tissue-transglutaminase (intestinal cd-associated antibodies), and the dietary proteins beta-lactoglobulin and ovalbumin in duodenal aspirate by enzyme-linked immunosorbent assay. Intraepithelial lymphocytes (IELs) were counted in histology sections, and the expression of HLA-DQ2 (A1*0501/B1*0201) was investigated by polymerase chain reaction. In 26 IBS patients, the effect of 6 months of gluten withdrawal was examined. RESULTS: Most cd patients expressed HLA-DQ2 and had increased intestinal cd-associated antibodies, whereas cd-associated serum IgA and IEL counts were increased in active cd in contrast to treated or latent cd. In IBS patients, 35% were HLA-DQ2-positive, 23% had increased IEL counts, and 0% and 30% had increased cd-associated antibodies in serum and duodenal aspirate, respectively. Furthermore, stool frequency and intestinal IgA decreased significantly under a gluten-free diet in the subgroups of HLA-DQ2-positive and intestinal antibody-positive IBS patients when compared with IBS patients without these markers. CONCLUSIONS: HLA-DQ2 expression and increased intestinal cd-associated antibodies are markers that can identify latent/potential cd in a subgroup of IBS patients who consequently appear to profit from a gluten-free diet.

Adolescent↗

Intramyocardial hematoma mimicking abnormal left ventricular trabeculation.

Intramyocardial hematoma may present as a tumor or pseudoaneurysm on echocardiography. A 68-year-old man was admitted with a subacute posterior wall infarction complicated by ventricular fibrillation. Echocardiography showed isolated left ventricular abnormal trabeculations, a finding suggesting an associated skeletal muscle disorder, in the lateral wall. At cardiac surgery, performed 6 weeks later because of severe 3-vessel disease, an intramyocardial hematoma of the lateral wall was excised, and myocardial and skeletal muscle biopsies were taken, which showed neither isolated left ventricular abnormal trabeculations nor skeletal muscle disorder. Postoperatively, echocardiography revealed no abnormal trabeculations.

Aged↗

Continuous venovenous hemofiltration improves arterial oxygenation in endotoxin-induced lung injury in pigs.

BACKGROUND: Hypoxemia is common in septic acute lung failure. Therapy is mainly supportive, and most trials using specific inhibitors of key inflammatory mediators (ie., tumor necrosis factor alpha, interleukin 1) have failed to prove beneficial. The authors investigated if a nonspecific blood purification technique, using zero-balanced high-volume continuous venovenous hemofiltration (CWH), might improve arterial oxygenation in a fluid-resuscitated porcine model of endotoxin-induced acute lung injury. METHODS: Piglets of both sexes weighing 25-30 kg were anesthetized and mechanically ventilated. After baseline measurements, animals received an intravenous infusion of 0.5 mg/kg endotoxin (Escherichia coli lipopolysaccharide). One hour after endotoxin, animals were randomly assigned to either treatment with CWH (endotoxin + hemofiltration, n = 6) or spontaneous course (endotoxin, n = 6). At 4 h after randomization, animals were killed. Hemofiltration was performed from femoral vein to femoral vein using a standard circuit with an EF60 polysulphone hemofilter. RESULTS: Endotoxin challenge induced arterial hypoxemia, an increase in peak inspiratory pressure, pulmonary hypertension, and systemic hypotension. Treatment with CWH did not improve systemic or pulmonary hemodynamics. However, arterial oxygenation was increased in endotoxin-challenged animals at 5 h after completion of endotoxin infusion, as compared with animals not receiving CVVH (arterialoxygen tension, 268+/-33 vs. 176+/-67 mm/Hg, respectively, P < 0.01). In addition, treatment with CWH attenuated the endotoxin-induced increase in peak inspiratory pressure and increased lung compliance. CONCLUSION: These results suggest that nonspecific blood purification with high-volume CWH improves arterial oxygenation and lung function in endotoxin-induced acute lung injury in pigs, independent of improved hemodynamics, fluid removal, or body temperature.

Animals↗

Frequency of clonal intraepithelial T lymphocyte proliferations in enteropathy-type intestinal T cell lymphoma, coeliac disease, and refractory sprue.

BACKGROUND: Clonal T cell receptor (TCR) gene rearrangements and loss of T cell antigens such as CD8 and TCR-beta in intraepithelial lymphocytes (IELs) may indicate the development of an enteropathy-type intestinal T cell lymphoma (EITCL) in patients with refractory sprue. AIMS: To define the diagnostic value of these markers in duodenal biopsies from patients with villous atrophy as a result of various underlying disorders. PATIENTS AND METHODS: Duodenal biopsies from eight patients with coeliac disease and five patients with villous atrophy caused by defined disorders were compared with three patients with refractory sprue evolving into overt EITCL, two patients with ulcerative jejunitis, and with eight patients with overt EITCL, for expression of CD3, CD4, CD8, and TCR-beta in IELs using immunohistochemistry and for clonal TCR-gamma gene rearrangements using polymerase chain reaction. In addition, biopsies from six consecutive patients with refractory sprue of uncertain cause were examined. RESULTS: Clonal TCR-gamma gene rearrangements were found in all resected tumours of patients with EITCL, in 3/8 duodenal biopsies of patients with EITCL, in 2/2 patients with ulcerative jejunitis, in 2/3 patients with refractory sprue evolving into overt EITCL, and in 1/6 patients with refractory sprue. No rearrangements were found in biopsies from patients with refractory sprue caused by defined disorders or those with coeliac disease. Clonality in duodenal biopsies was associated with an abnormal phenotype of IELs in all cases and in all but one case in patients with evidence of underlying coeliac disease. Specificity for detection of an EITCL using immunohistology was 77% for CD8 and for TCR-beta staining, and 100% for detection of a clonal TCR-gamma gene rearrangement. Sensitivity was 62% for staining with CD8 and clonality investigation, while sensitivity reached 100% for TCR-beta staining in all investigated patients with EITCL. CONCLUSIONS: Clonal proliferations of phenotypically abnormal IELs in refractory sprue represent an early manifestation of EITCL, for which the term "sprue-like intestinal T cell lymphoma" is proposed. This constellation is also found in duodenal biopsies from patients with an overt EITCL and is not related to other sprue syndromes, resulting in a high specificity for detection of an EITCL or refractory sprue evolving into EITCL. Overt EITCL may develop directly from coeliac disease without a precursor lesion (refractory sprue with clonal IELs) being demonstrable in duodenal biopsies or via a "sprue-like intestinal T cell lymphoma". This latter entity is a complication of coeliac disease.

Adolescent↗

Congenital deficiency of nitric oxide synthase 2 protects against endotoxin-induced myocardial dysfunction in mice.

BACKGROUND: Sepsis can be complicated by severe myocardial dysfunction and is associated with increased nitric oxide (NO) production by inducible NO synthase (NOS2). To investigate the role of NOS2 in endotoxin-induced myocardial dysfunction in vivo, we studied wild-type and NOS2-deficient mice. METHODS AND RESULTS: Serial echocardiographic parameters of myocardial function were measured before and at 4, 7, 16, and 24 hours after an endotoxin challenge. Seven hours after challenge with either endotoxin or saline, systemic and left ventricular pressures were measured, and the first derivative of left ventricular developed pressure (dP/dt), slope of the end-systolic pressure-dimension relationship (Slope(LVESPD)), and time constant of isovolumic relaxation (tau) were calculated. Endotoxin challenge in wild-type mice decreased left ventricular fractional shortening, velocity of circumferential shortening, dP/dt(max), Slope(LVESPD), and dP/dt(min) and increased time constant tau. Endotoxin-induced myocardial dysfunction was associated with increased ventricular NOS2 gene expression and cGMP concentrations. Seven hours after endotoxin challenge, NOS2-deficient mice had greater fractional shortening, dP/dt(max), and Slope(LVESPD) than did endotoxin-challenged wild-type mice. Measures of diastolic function, dP/dt(min) and time constant tau, were preserved in endotoxin-challenged NOS2-deficient mice. After endotoxin challenge in wild-type mice, early (3-hour) inhibition of NOS2 with L-N:(6)-(1-iminoethyl)lysine hydrochloride prevented, whereas later (7-hour) inhibition could not reverse, endotoxin-induced myocardial dysfunction. CONCLUSIONS: These results suggest that NOS2 is required for the development of systolic and diastolic dysfunction in murine sepsis.

Animals↗