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81.
BACKGROUND: Obstructive sleep apnoea has been demonstrated to induce gastrooesophageal reflux through highly negative intrathoracic pressure during the attacks. However, we believe that gastrooesophageal reflux on its part may favour or aggravate the apnoea attacks. AIMS: We investigated whether the treatment of gastrooesophageal reflux with omeprazole is able to decrease apnoea attacks. PATIENTS AND METHODS: Twenty patients (mean age 55.4 years, range 49-73 years; 17 males) with confirmed obstructive sleep apnoea at overnight polysomnography and pathological gastrooesophageal reflux at ambulatory 24-h oesophageal pHmetry were asked to note in a diary the occurrence of apnoea attacks for a basal period of 4 weeks. Subsequently, the patients were randomly and in a double-blind manner treated with omeprazole 20mg (10 patients, group A) or placebo (10 patients, group B) by giving 1 cp 30 min before breakfast and 1 cp 30 min before dinner for another 6 weeks with a diary documentation. The results were averaged weekly and over the entire treatment duration and a statistical comparison was made between the groups and within each group before and after treatment. RESULTS: The mean weekly frequency of apnoea attacks of group A during the entire period of treatment with omeprazole was significantly decreased with respect to the basal period and was significantly lower than that of group B. The weekly frequency of apnoea attacks in group A started to be significantly lower from the third week than the corresponding values of both group B and the basal period, reaching a decrease of about 73% in the sixth week. CONCLUSION: The occurrence of apnoea attacks progressively decreased during the treatment of gastrooesophageal reflux with omeprazole. This fact suggests that gastrooesophageal reflux may play a role in triggering and/or worsening obstructive sleep apnoea.  相似文献   
82.
In the present study we evaluated the relation among histology, H. pylori, IgG to H. pylori, gastric emptying, and acid secretion in 43 patients with fundic atrophic gastritis. On the basis of gastric acid secretion, patients were divided into three subgroups: patients with preserved acid secretion (Group 1), patients with hypochlorhydria (Group 2), and patients with achlorhydria (Group 3). Fundic glandular atrophy was more severe in hypoachlorhydric patients than in those with preserved acid secretion (P < 0.05 vs Group 2, P < 0.005 vs Group 3). H. pylori colonization was found in 94% of patients in Group 1, in 61% of patients in Group 2, and in only 8% of patients in Group 3 (P < 0.001 vs Group 1, P < 0.05 vs Group 2). Conversely, serological positivity to H. pylori was high in all three subgroups of patients (100% in Group 1, 77% in Group 2, 92% in Group 3). Gastric emptying was delayed in atrophic patients, particularly in those with hypoachlorhydria. Our data suggest that fundic atrophic gastritis represents a possible end stage of H. pylori infection, characterized by a progressive disappearance of the bacterium and a progressive deterioration of gastric functions.  相似文献   
83.
The variability of plasma propranolol concentrations has been determined in a large group of patients being treated with the drug. Although the average patient achieved a therapeutic plasma level with 160 mg/day, there was marked interpatient variation. This was found to be primarily the result of differences in effective absorption of the drug, which averaged 46% of the oral dose but ranged from 20 to 80%. Propranolol disappeared from plasma with a half-life of 4.7 hours and its removal appeared to follow dose independent kinetics with no evidence of saturation of hepatic metabolism. The derived pharmacokinetic values of volume of distribution and clearance rate have been used to provide guidelines for initiating propranolol therapy intravenously, and the schedule of 8 mg as a loading dose and 0.02 mg/min as a sustaining dose has been suggested.  相似文献   
84.

Background:

Monoamine reuptake inhibitors exhibit unique clinical profiles that reflect distinct engagement of the central nervous system (CNS) transporters.

Methods:

We used a translational strategy, including rodent pharmacokinetic/pharmacodynamic modeling and positron emission tomography (PET) imaging in humans, to establish the transporter profile of TD-9855, a novel norepinephrine and serotonin reuptake inhibitor.

Results:

TD-9855 was a potent inhibitor of norepinephrine (NE) and serotonin 5-HT uptake in vitro with an inhibitory selectivity of 4- to 10-fold for NE at human and rat transporters. TD-9855 engaged norepinephrine transporters (NET) and serotonin transporters (SERT) in rat spinal cord, with a plasma EC50 of 11.7ng/mL and 50.8ng/mL, respectively, consistent with modest selectivity for NET in vivo.Accounting for species differences in protein binding, the projected human NET and SERT plasma EC50 values were 5.5ng/mL and 23.9ng/mL, respectively. A single-dose, open-label PET study (4–20mg TD-9855, oral) was conducted in eight healthy males using the radiotracers [11C]-3-amino-4- [2-[(di(methyl)amino)methyl]phenyl]sulfanylbenzonitrile for SERT and [11C]-(S,S)-methylreboxetine for NET. The long pharmacokinetic half-life (30–40h) of TD-9855 allowed for sequential assessment of SERT and NET occupancy in the same subject. The plasma EC50 for NET was estimated to be 1.21ng/mL, and at doses of greater than 4mg the projected steady-state NET occupancy is high (>75%). After a single oral dose of 20mg, SERT occupancy was 25 (±8)% at a plasma level of 6.35ng/mL.

Conclusions:

These data establish the CNS penetration and transporter profile of TD-9855 and inform the selection of potential doses for future clinical evaluation.  相似文献   
85.
86.
Isolated mitochondrial complex IV (cytochrome c oxidase) deficiency is an important cause of mitochondrial disease in children and adults. It is genetically heterogeneous, given that both mtDNA-encoded and nuclear-encoded gene products contribute to structural components and assembly factors. Pathogenic variants within these proteins are associated with clinical variability ranging from isolated organ involvement to multisystem disease presentations. Defects in more than 10 complex IV assembly factors have been described including a recent Lebanese founder mutation in PET100 in patients presenting with Leigh syndrome. We report the clinical and molecular investigation of a patient with a fatal, neonatal-onset isolated complex IV deficiency associated with multiorgan involvement born to consanguineous, first-cousin British Asian parents. Exome sequencing revealed a homozygous truncating variant (c.142C>T, p.(Gln48*)) in the PET100 gene that results in a complete loss of enzyme activity and assembly of the holocomplex. Our report confirms PET100 mutation as an important cause of isolated complex IV deficiency outside of the Lebanese population, extending the phenotypic spectrum associated with abnormalities within this gene.  相似文献   
87.
Monocytoid B-cell lymphoma (MBCL) is a newly recognized B-cell neoplasm of uncertain histogenesis. The cytologic features of the neoplastic monocytoid B lymphocytes are virtually identical to those of hairy cell leukemia (HCL). As with HCL, progression of MBCL to a higher histologic grade is very unusual. However, whereas circulating leukemic cells are a characteristic feature of HCL, peripheral blood involvement has not been reported in MBCL. We recently studied a patient with MBCL of the spleen and axillary lymph nodes who developed peripheral blood involvement by MBCL cells. Unlike the cells of HCL, the circulating MBCL cells exhibited strong acid phosphatase activity that was tartrate sensitive. The leukemic cells had the antigenic phenotype IgM lambda, CD20+, CD11c+, CD5-, CD25(TAC)-, and PCA-1-. Immunogenetic studies of both lymph node and peripheral blood cells revealed identical immunoglobulin heavy-chain gene rearrangements. When compared with a series of HCL, the immunophenotype was similar except for the absence of PCA-1 and TAC. Progression of the MBCL to a large cell lymphoma, also expressing IgM lambda, was documented in an abdominal lymph node of this patient. Therefore, although rare, peripheral blood involvement by lymphoma cells may occur during the course of MBCL and should be distinguished from HCL with cytochemical and immunophenotypic studies. In addition, comparison of the clinical, pathologic, and immunologic features of MBCL with those of other low-grade B-cell neoplasms suggests that a close lineage relationship exists between MBCL and HCL.  相似文献   
88.
Bhalla  K; Holladay  C; Arlin  Z; Grant  S; Ibrado  AM; Jasiok  M 《Blood》1991,78(10):2674-2679
Hematopoietic growth factors (HGFs) interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) individually have been shown to increase the percentage of acute myeloid leukemia (AML) blasts in S phase and enhance the cytotoxic effects of Ara-C against these blasts in culture. We compared in vitro the effects of a combined treatment with GM-CSF (10 ng/mL) plus IL-3 (10 ng/mL) on the metabolism and cytotoxicity of Ara-C in normal bone marrow mononuclear cells (NBMMC) and AML blasts. NBMMC from six healthy volunteers and AML blasts from 10 patients were incubated for 20 hours with or without IL- 3 plus GM-CSF, followed by a concurrent treatment with Ara-C for 4 additional hours. Exposure to the HGFs and Ara-C produced significantly higher intracellular Ara-CTP levels as well as higher Ara-CTP/dCTP pool ratios in AML blasts as compared with NBMMC. Treatment with HGFs resulted in [3H] Ara-C DNA incorporation that was significantly higher in AML blasts versus NBMMC. This selective improvement of Ara-C metabolism in AML blasts was associated with an enhanced Ara-C-mediated leukemia colony-forming unit (CFU) growth inhibition. In contrast, exposure to HGFs resulted in an improved colony growth of normal CFU granulocyte-monocyte and CFU-granulocyte, erythroid, monocyte, megakaryocyte. These in vitro studies indicate that a combined treatment with IL-3 plus GM-CSF may improve the selectivity of Ara-C against AML blasts.  相似文献   
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