Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Because chronic obstructive pulmonary disease (COPD) is well known to induce peripheral neuropathy and resistance to ischemic nerve conduction failure (RICF), we performed a case-control study examining peripheral nerve function during ischemia in 17 patients with severe obstructive sleep apnea (OSA) without daytime hypoxemia and 10 control subjects. Median nerve conduction was studied before, during, and after a 30-min period of ischemia. Preischemic sensory and mixed nerve potential amplitudes and sensory conduction velocity were lower in OSA patients than in control subjects despite higher supramaximal stimulation. During ischemia, seven OSA patients manifested RICF (OSA-RICF), whereas both the other 10 patients, who were nonresistant to ischemic conduction failure (OSA-NR), and control subjects did not. OSA-RICF patients had the lowest initial nerve-potential amplitude, whereas OSA-NR patients had a response intermediate between that of control subjects and OSA-RICF patients. OSA-RICF patients had a lower mean nocturnal SaO2 and a higher body mass index (BMI) and duration of SaO2 < 70% than did OSA-NR patients. Seven patients (four OSA-RICF and three OSA-NR) were reevaluated after at least 2 mo of treatment with nasal continuous positive airway pressure (nCPAP). RICF disappeared in all OSA-RICF patients, whereas preischemic nerve conduction parameters were unchanged in both OSA-RICF and OSA-NR patients. Thus OSA patients have peripheral nerve dysfunction whose severity is partly related to the level of nocturnal hypoxemia. Abnormal preischemic nerve conduction suggests axonal lesions, whereas RICF, which appears to be a sensitive but nonspecific tissue marker of the severity of hypoxemia, may result from adaptative mechanisms.
 ...
PMID:Peripheral neuropathy in sleep apnea. A tissue marker of the severity of nocturnal desaturation. 987 41

The present review is focused on chronic RV pressure overload or Cor Pulmonale as it may occur in the setting of two distinct disorders: those associated with abnormal pulmonary gas exchange (hypoxemia and/or hypercapnia) where chronic obstructive pulmonary disease (COPD) is the leading cause, and those associated with pulmonary vascular obstruction where primary pulmonary hypertension (PDDH) is the representative example. The clinical curse, prognostic, implications, and therapeutic strategies differ considerably in these two clinical entities. Right ventricular failure (RVF) may adversely influence the natural history and prognosis of patients with diverse cardiopulmonary disorders. It has been long established that right ventricular (RV) ischemia, RV overload, and RV pressure overload, alone or in combination, are the main factors involved in the pathogenesis of RVF. From the pathophysiologic point of view, RVF of COPD is more a congestive type of failure, in which activation of renin-angiotensin system is involved. In PPH, a low cardiac output state is predominant and the precise mechanism of RVF remains unknown. Current evidence in favor of the pathogenetic role of ischemia, adrenergic overdrive, and genetic determination are all reviewed during the course.
 ...
PMID:[Right ventricle insufficiency in pulmonary arterial hypertension. Physiopathologic considerations]. 1156 26

In an effort to identify preoperative and perioperative factors impacting outcome in repair of juxtarenal abdominal aortic aneurysm (JRAAA), hospital records and CT scans (for calcification, intraluminal thrombus, and aortic diameter) of all patients undergoing JRAAA repair over the past 10 years were reviewed. The 87 men and 25 women had a mean age of 72, and a mean maximal aortic diameter of 6.2 cm. Renal artery stenosis (RAS) and iliac disease were present in 13 (11%) and 40 patients (35%), respectively. Comorbidities included coronary artery disease (n = 49, 44%), COPD (n = 28, 25%), diabetes mellitus (n = 10, 9%), and preoperative renal insufficiency (PRI; Cr >1.4 mg/dL; n = 14, 12%). A midline incision was used in most of the patients (n = 98, 88%). The proximal aortic clamp was placed in the supraceliac (SC) position in 92 (82%) patients, and directly above one or both renal arteries in 20 (18%) patients. The overall mortality was 6% (n = 7). Cardiac complications occurred in 26 patients (23%); pulmonary, in 22 (20%); renal, in 14 (12%); and gastrointestinal, in 10 (9%). No patient experienced mesenteric ischemia. Mean elevation in creatinine was greater in patients with PRI (1.8 mg/dL vs. 0.13 mg/dL, p = 0.04). Mean blood loss (EBL) was 2701 +/- 189 cc, and mean LOS was 16.1 +/- 1.7 days. Age >70 was associated with increased length of stay (LOS) (12.1 days vs. 18.6 days, p = 0.05) and higher mortality (0 vs. 10%, p = 0.02); otherwise there were no significant relationships between pre- and perioperative parameters and any of the measured outcomes including death, postoperative RI, and LOS. Preferential SC clamping may substantially reduce complications of JRAAA repair (such as mesenteric and renal ischemia) related to proximal cuff disease, but cannot overcome the deleterious affects of advanced age and PRI.
 ...
PMID:Optimal operative strategies in repair of juxtarenal abdominal aortic aneurysms. 1252

Based on data reported to the United Network for Organ Sharing through December 2001: 1. The number of heart transplant procedures performed in the United States increased slightly (< 1%) during each of the last 2 complete years from 2,187 transplants during 1999 to 2,197 transplants during 2000, followed by an additional increase in 2001 to 2,202 transplants. A more substantial increase was seen in the number of lung transplants performed: from 890 transplants in 1999 to 956 in 2000 (+7%) and an additional increase to 1,053 transplants in 2001 (+10%). Fewer than 30 heart-lung transplants were performed in 2001. Living-donor lung transplants comprised 2-3% of lung transplants performed between 1995-2001. 2. Pediatric recipients were more frequently on life support in the ICU; more likely to have an ischemia time of at least 4 hours; more often gender mismatched; and more often ABO-compatible rather than ABO-identical with the donor than adult recipients for all thoracic organ types. 3. The most common indication for transplant since 1996 in adult heart recipients was coronary artery disease (50%), followed closely by cardiomyopathy (42%). Among pediatric heart recipients, the 2 most common indications: cardiomyopathy (46%) and congenital heart disease (43%) accounted for approximately 90% of the transplants. The indications for lung transplants were more disparate. In adult lung recipients, the 4 most common diagnoses (COPD - 42%, IPF - 17%, CF - 15% and A1A - 9%) encompassed more than 80% of the transplants. More than half of the pediatric lung transplants were performed in recipients with CF. The 3 most frequently cited indications for adult heart-lung transplant recipients (Eisenmenger's Syndrome, other congenital heart diagnoses and PPH) accounted for greater than 75% of the transplants. 4. Approximately 30-35% of adult heart transplants since 1999 have been performed in patients who were Status 1A. For pediatric transplant recipients, Status 1A comprised 60-70% of the transplants. 5. The one-year survival rate for transplants performed during the first three-quarters of 2001 was 85% for both adult and pediatric heart transplant recipients and 77% for both adult and pediatric recipients of lung transplants. For adult heart-lung transplants performed during 2000, the one-year survival rate was 69%. 6. The long-term patient survival rates were: 39% for adult heart recipients and 50% for pediatric heart recipients at 12 years; 18% at 11 years for adult lung recipients and 31% at 9 years for pediatric lung recipients; and 24% at 11 years for adult heart-lung recipients and 21% at 8 years for pediatric heart-lung recipients. 7. Drug-treated rejection and drug-treated infection were reported to occur before discharge in approximately 20-40% of transplant recipients, with the exception of pediatric lung and heart-lung recipients, with rates varying by organ and age group. Drug-treated infections were reported before discharge in more than 60% of pediatric lung recipients and approximately half of pediatric heart-lung recipients. 8. Approximately 60% of adult heart recipients and 70% of pediatric heart recipients were hospitalized at least once during the first 3 years following their transplant.
 ...
PMID:Thoracic organ transplantation in the US. 1297 35

The definition of proper patient selection criteria remains a prominent item in constant need of attention. While the concept of gathering evidence in order to determine practice continues to be hopelessly ambiguous, it can never be emphasized too much that these univariate results are just a first foray into analysing predictors of survival; all following results should be regarded and interpreted in this perspective. HEART TRANSPLANT SURVIVAL: The 3-year survival rate for heart transplant recipients under age 16 was 83% versus 72% for adult recipients. Acutely retransplanted adult heart recipients had a 3-year survival rate of 36% compared with 72% for recipients of a first heart allograft. Patients suffering from DCM had the best survival rates at 3 years (74%) compared with patients suffering from CAD (70%) or from another end-stage heart disease (67%). With advancing age of the adult recipient, the mortality risk increased. Patients aged 16-40 had a 3-year survival rate of 77%, compared with 74%, 70% and 61% for transplant recipients aged 41-55, 56-65 and over age 65, respectively. The 3-year survival rates for adult recipients transplanted with an heart allograft from a donor aged under 16 or between 16-44 were 78% and 74%, compared with 66% and 63% for donors aged 45-55 and over 55, respectively. The 3-year survival rates for recipients of hearts with cold ischemic times under 2 hours, 2-3, 3-4, 4-5, 5-6 and more than 6 hours were 74%, 75%, 70%, 65%, 54% and 40%, respectively. Transplanting a female donor heart into a male recipient was associated with the worst prognosis: the 3-year survival rates were 73%, 71%, 66% and 76%, respectively, for the donor/recipient groups male/male, male/female, female/male and female/female, respectively. When the donor-to-recipient body weight ratio was below 0.8, the 3-year survival rate was 64%, compared to 72% for weight-matched pairs and 74% for patients who received a heart from an oversized donor (p=0.004). Better survival rates were obtained for better HLA-matched transplants. The 3-year survival rates were 75%, 89%, 78%, 78%, 69%, 72%, and 71% for HLA-A,-B,-DR zero, 1, 2, 3, 4, 5 and 6 mismatched groups, respectively (p=0.04). Survival was significantly associated with the CMV serologic status of the donor and recipient; the 3-year survival rates were: D+/R+, 71%; D+/R-, 69%; D- R-, 76%; and D-/R+, 76% (p=0.04). Patients in an ICU had a 3-year survival rate of 62%, compared to 72% for patients in a general ward and 74% for outpatients (p<0.0001). Patients that were on a VAD and there-upon transplanted had a 3-year survival rate of 65%, compared to 73% for patients without a VAD (p=0.004). Being on a ventilator was a major risk factor for death after transplantation; patients on ventilator support at the time of the transplant had a 3-year survival rate of 52% compared to 73% for the other patients (p<0.0001). LUNG TRANSPLANT SURVIVAL: The 3-year survival rate for children (73%) appeared to be better than the adult rate (61%; p=0.8). Adult lung transplant survival was significantly worse in the case of a repeat lung transplant; a 3-year retransplant survival rate of 42% was obtained compared with 61% for first transplants (p=0.049). With respect to the underlying end-stage lung disease, no statistically significant difference in long-term survival could be detected in this cohort. The 3-year survival rates were: 62% for COPD/Emphysema, 70% for CF, 58% for IPF, 64% for Alpha-1 ATD and 56% for PPH (p=0.2). Our data demonstrated no effect of the recipient's age on long-term lung transplant survival, except for 2 senior patients in this cohort. At 3-years the survival rates for recipients aged 16-40, 41-55 and 56-65 were 65%, 60% and 62%, respectively (p=0.05). The 3-year survival rates for transplants performed with lungs from donors aged under 16, 16-44, 45-55 and over 55 was 57%, 64%, 55% and 62%, respectively (p=0.1) No association between the duration of cold ischemic time and 3-year survival was observed; under 3 hours, 3-4, 4-5, 5-6 and over 6 hours of ischemia resulted in 3-year survival rates of 53%, 59%, 64%, 68% and 57%, respectively (p=0.2). Early posttransplant outcome tended to be better for gender-matched transplants, while transplanting a female donor lung into a male recipient was associated with the worst prognosis. The 3-year survival rates were 65% for male/male, 63% for male/female, 48% for female/male and 61% for female/female (p=0.009). No effect of donor-to-recipient weight match was observed in this Eurotransplant cohort; when the donor-to-recipient weight ratio was below 0.8, the 3-year survival rate was 57%, compared with 59% for weight-matched pairs and 64% for patients who received a lung from an oversized donor (p=0.5). Long-term survival after lung transplantation was influenced by HLA matching. The 3-year survival rates were 100%, 68%, 70%, 65%, 54% and 55% for the HLA-A,-B,-DR 1, 2, 3, 4, 5 and 6 mismatched groups, respectively (p=0.06). A donor CMV+ and recipient CMV- match was a risk factor for long-term mortality, with 3-year survival rates of 56% for D+/R+, 55% for D+/R-, 71% for D-/R- and 62% for D-/R+ transplants (p=0.046). En-bloc transplantation of both lungs yielded worse early results, but the 3-year survival rates for patients who underwent single (60%), bilateral sequential double lung (63%) and en-bloc double lung transplantation (56%) were not different (p=0.2). Ventilator dependency was associated with a significantly reduced survival at 3 years. Patients on a ventilator support at the time of the transplant had a 3-year survival rate of 48% compared with 63% for other patients (p=0.006).
 ...
PMID:Three-year survival rates for all consecutive heart-only and lung-only transplants performed in Eurotransplant, 1997-1999. 1538

Acid-base balance is altered in a variety of common pathologies, including COPD, ischemia, renal failure, and cancer. Because of robust cellular pH homeostatic mechanisms, most of the pathological alterations in pH are expressed as changes in the extracellular, systemic pH. There are data to indicate that altered pH is not simply an epiphenomenon of metabolic or physiologic imbalance but that chronic pH alterations can have important sequelae. MRSI and MRI measurements indicate that pH gradients of up to 1.0 pH unit can exit within 1-cm distance. Although measurement of blood pH can indicate systemic problems, it cannot pinpoint the lesion or quantitatively assess the magnitude of excursion from normal pHe. Hence, there is a need to develop pHe measurement methods with high spatiotemporal resolution. The two major approaches being investigated include magnetization transfer methods and relaxation methods. pH-dependent MT effects can observed with endogenous signals or exogenously applied CEST agents. While endogenous signals have the advantage of being fully noninvasive and relatively straightforward to apply, they lack a full biophysical characterization and dynamic range that might be afforded by future CEST agents. pH-dependent relaxivity also requires the injection or infusion of exogenous contrast reagents. In both MT and relaxographic approaches, the magnitude of the effect, and, thus, the ability to quantify pHe, depends on a spatially and temporally varying concentration of the CR. A number of approaches have been proposed to solve this problem and, once it is solved, pH imaging methods will be applicable to human clinical pathologies.
 ...
PMID:pH imaging. A review of pH measurement methods and applications in cancers. 1556

Chronic dyspnea is defined as dyspnea lasting more than one month. In approximately two thirds of patients presenting with dyspnea, the underlying cause is cardiopulmonary disease. Establishing an accurate diagnosis is essential because treatment differs depending on the underlying condition. Asthma, congestive heart failure, chronic obstructive pulmonary disease, pneumonia, cardiac ischemia, interstitial lung disease, and psychogenic causes account for 85 percent of patients with this principal symptom. The history and physical examination should guide selection of initial diagnostic tests such as electrocardiogram, chest radiograph, pulse oximetry, spirometry, complete blood count, and metabolic panel. If these are inconclusive, additional testing is indicated. Formal pulmonary function testing may be needed to establish a diagnosis of asthma, chronic obstructive pulmonary disease, or interstitial lung disease. High-resolution computed tomography is particularly useful for diagnosing interstitial lung disease, idiopathic pulmonary fibrosis, bronchiectasis, or pulmonary embolism. Echocardiography and brain natriuretic peptide levels help establish a diagnosis of congestive heart failure. If the diagnosis remains unclear, additional tests may be required. These include ventilation perfusion scans, Holter monitoring, cardiac catheterization, esophageal pH monitoring, lung biopsy, and cardiopulmonary exercise testing.
 ...
PMID:Evaluation of chronic dyspnea. 1586 93

48 year old man with chronic obstructive pulmonary disease (COPD) secondary to pulmonary hypertension with domiciliary non-invasive ventilation was seen. He came to the emergency department with acute exacerbation of COPD. The patient was admitted to the Cardiology Service with the diagnosis of congestive heart failure. Diagnostic imaging (chest X-ray, transthoracic Doppler-echocardiography, multidetector row spiral CT and myocardial perfusion imaging) revealed an enlarged right ventricle. ECG was consistent with right ventricular failure. The heart perfusion imaging (pharmacologic stress testing with dobutamine) showed cor pulmonale and right ventricle ischemia induced by drug stress with dobutamine. Although right ventricle myocardial chronic dysfunction rarely causes right ventricular failure, it can occur when cor pulmonale and ischemia heart disease are present.
 ...
PMID:[Ischemia of right ventricle and cor pulmonale]. 1612 9

We have previously shown that 11 ent-kauranes isolated from the stems of Annona squamosa exhibited immunomodulating effects in leukocytes. In this study, a cellular model using isolated human neutrophils, which are important in the pathogenesis of rheumatoid arthritis, ischemia-reperfusion injury, chronic obstructive pulmonary disease, asthma and other inflammatory diseases, was established in order to elucidate the anti-inflammatory functions of 16beta,17-dihydroxy-ent-kauran-19-oic acid (1). Reactive oxygen species (ROS) and granule proteases produced by neutrophils contribute to the pathogenesis of inflammatory diseases. Compound 1 inhibited the generation of superoxide anion, the formation of ROS, and the release of elastase in formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP)-activated human neutrophils in a concentration-dependent manner with IC (50) values of 3.95 +/- 0.68, 12.20 +/- 2.16, and 12.52 +/- 2.26 microM, respectively. The anti-inflammatory actions were not attributable to cytotoxicity because incubation of the neutrophils with 1 did not result in lactate dehydrogenase release. Compound 1 did not display antioxidant or superoxide anion-scavenging activity. Furthermore, neither subcellular NADPH oxidase activity nor cAMP-dependent pathways were altered by 1. Compound 1 significantly inhibited rapid calcium release from internal calcium stores induced by FMLP but not by thapsigargin. In summary, the presented results indicate that the inhibitory effects of 1 on respiratory burst and degranulation of human neutrophils are through the inhibition of cytosolic calcium mobilization, but not via the cAMP-dependent pathways.
 ...
PMID:An anti-inflammatory ent-kaurane from the stems of Annona squamosa that inhibits various human neutrophil functions. 1625 20

Pulmonary oxidant stress plays an important pathogenetic role in disease conditions including acute lung injury/adult respiratory distress syndrome (ALI/ARDS), hyperoxia, ischemia-reperfusion, sepsis, radiation injury, lung transplantation, COPD, and inflammation. Reactive oxygen species (ROS), released from activated macrophages and leukocytes or formed in the pulmonary epithelial and endothelial cells, damage the lungs and initiate cascades of pro-inflammatory reactions propagating pulmonary and systemic stress. Diverse molecules including small organic compounds (e.g. gluthatione, tocopherol (vitamin E), flavonoids) serve as natural antioxidants that reduce oxidized cellular components, decompose ROS and detoxify toxic oxidation products. Antioxidant enzymes can either facilitate these antioxidant reactions (e.g. peroxidases using glutathione as a reducing agent) or directly decompose ROS (e.g. superoxide dismutases [SOD] and catalase). Many antioxidant agents are being tested for treatment of pulmonary oxidant stress. The administration of small antioxidants via the oral, intratracheal and vascular routes for the treatment of short- and long-term oxidant stress showed rather modest protective effects in animal and human studies. Intratracheal and intravascular administration of antioxidant enzymes are being currently tested for the treatment of acute oxidant stress. For example, intratracheal administration of recombinant human SOD is protective in premature infants exposed to hyperoxia. However, animal and human studies show that more effective delivery of drugs to cells experiencing oxidant stress is needed to improve protection. Diverse delivery systems for antioxidants including liposomes, chemical modifications (e.g. attachment of masking pegylated [PEG]-groups) and coupling to affinity carriers (e.g. antibodies against cellular adhesion molecules) are being employed and currently tested, mostly in animal and, to a limited extent, in humans, for the treatment of oxidant stress. Further studies are needed, however, in order to develop and establish effective applications of pulmonary antioxidant interventions useful in clinical practice. Although beyond the scope of this review, antioxidant gene therapies may eventually provide a strategy for the management of subacute and chronic pulmonary oxidant stress.
 ...
PMID:Antioxidant strategies in respiratory medicine. 1640 15


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>