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31.
OBJECTIVES: In managing patients with bleeding peptic ulcers, prevention of rebleeding is a particular challenge to hemostasis and fibrinolysis, both of which involve reactions that are impaired in acidic gastric environment. Therefore, such patients are expected to benefit from profound acid suppression. The present investigation aimed to establish a safe and, with regard to pH elevation, effective treatment that, based on in vitro evidence, should provide clinical benefit in this patient population. METHODS: Patients with acute bleeding peptic ulcers (Forrest Ia, Ib, IIa) after successful endoscopic hemostasis were enrolled in two pilot studies (N = 20 each). They were given an intravenous bolus injection of 80 mg of pantoprazole immediately followed by continuous infusion of either 6 mg/h or 8 mg/h pantoprazole for 72 h. Intragastric pH was measured continuously over 24 h and, if possible, for up to 48 h. RESULTS: Intragastric pH increased rapidly to values of about 6 with both treatments. For the 0-24 h period, the median pH values were 6.1 (68% range 4.5-7.4) and 6.1 (68% range 5.2-6.7) in patients receiving 6 mg/h and 8 mg/h continuous infusion, respectively; the values for the 0-48 h period were 5.9 (4.9-6.7) and 6.3 (5.5-7.0), respectively. The median percentage time that pH was > or =6 during the 0-48 h interval was 47% (68% range 28-89) for the 6 mg/h treatment group and 64% (68% range 41-84) for the 8 mg/h treatment group. Both treatment regimens with pantoprazole were well tolerated based on electrocardiographic measurements, vital signs, clinical laboratory values, and adverse events. CONCLUSIONS: Compared with the infusion with 6 mg/h pantoprazole, the continuous infusion of 8 mg/h pantoprazole showed a lower interindividual variability of the intragastric pH and a greater percentage of time that pH was >/ or =6. Thus, with regard to safety and efficacy, an initial 80-mg bolus injection, followed by 8 mg/h continuous infusion, seems to be the adequate treatment in patients with a high risk of rebleeding.  相似文献   
32.
Resistance toward imatinib and other BCR/ABL tyrosine kinase inhibitors remains an increasing clinical problem in the treatment of advanced stages of chronic myeloid leukemia (CML). We recently have identified the heat shock protein 32 (Hsp32)/heme oxygenase-1 (HO-1) as a BCR/ABL-dependent survival molecule in CML cells. We here show that silencing Hsp32/HO-1 in CML cells by an siRNA approach results in induction of apoptosis. Moreover, targeting Hsp32/HO-1 by either pegylated zinc protoporphyrine (PEG-ZnPP) or styrene maleic acid-micelle-encapsulated ZnPP (SMA-ZnPP) resulted in growth inhibition of BCR/ABL-transformed cells. The effects of PEG-ZnPP and SMA-ZnPP were demonstrable in Ba/F3 cells carrying various imatinib-resistant mutants of BCR/ABL, including the T315I mutant, which exhibits resistance against all clinically available BCR/ABL tyrosine kinase inhibitors. Growth-inhibitory effects of PEG-ZnPP and SMA-ZnPP also were observed in the CML-derived human cell lines K562 and KU812 as well as in primary leukemic cells obtained from patients with freshly diagnosed CML or imatinib-resistant CML. Finally, Hsp32/HO-1-targeting compounds were found to synergize with either imatinib or nilotinib in producing growth inhibition in imatinib-resistant K562 cells and in Ba/F3 cells harboring the T315I mutant of BCR/ABL. In summary, these data show that HO-1 is a promising novel target in imatinib-resistant CML.  相似文献   
33.
Journal of Gastroenterology - As extra-intestinal manifestations (EIMs) are frequent in inflammatory bowel disease (IBD) and affect morbidity and sometimes even mortality, vigilance in the...  相似文献   
34.
35.
Enteric-coated tablets leave the stomach mainly during the interdigestive phase. Composition as well as time of ingestion of meals may influence their gastric emptying considerably. In 12 normal volunteers gastric emptying of a plastic tablet with a metal core was followed by a metal detector in relation to different compositions and various times of ingestion of meals. With an empty stomach and after ingestion of 250 ml water, the mean time for gastric emptying of the tablet was 38 +/- 11 min (mean +/- SEM) and 38 +/- 8 min. Two hundred fifty milliliters of milk (652 kJ) and a formula diet (1000 kJ) delayed gastric emptying time to 128 +/- 14 and 152 +/- 6 min, respectively (P less than 0.05). Breakfast (2200 kJ) further retarded gastric emptying compared with both liquids to 249 +/- 24 min (P less than 0.05). There was a close correlation between nutritive density and gastric emptying of the tablet (r = 0.92; P less than 0.001). Main meals also delayed gastric emptying of tablets when compared to empty stomach (P less than 0.05). A snack after breakfast further delayed gastric emptying from 201 +/- 10 to 278 +/- 19 min (P less than 0.05). The largest delay was observed following ingestion of breakfast, lunch, dinner, and additional snacks (509 +/- 220 min). We conclude that the delay of gastric emptying of enteric-coated tablets by food is related to its nutritive density and eating habits. The gastric emptying of an enteric coated tablet that is ingested early in the morning may be delayed until late at night when several meals and snacks are ingested during the day, leading to unwanted alterations in bioavailability and to possible adverse effects.  相似文献   
36.

Background

The relationship between war-related trauma exposure, depressive symptoms and multiple risk behaviors among adolescents is less clear in sub-Saharan Africa.

Methods

We analyzed data collected from a sample of school-going adolescents four years postwar. Participants completed interviews assessing various risk behaviors defined by the Youth Self Report (YSR) and a sexual risk behavior survey, and were screened for post-traumatic stress, anxiety and depression symptoms based on the Impact of Events Scale Revised (IESR) and Hopkins Symptom Checklist for Adolescents (HSCL-37A) respectively. Multivariate logistic regression was used to assess factors independently associated with multiple risk behaviors. The logistic regression model of Baron and Kenny (1986) was used to evaluate the mediating role of depression in the relationship between stressful war events and multiple risk behaviors.

Results

Of 551 participants, 139 (25%) reported multiple (three or more) risk behaviors in the past year. In the multivariate analyses, depression symptoms remained uniquely associated with multiple risk behavior after adjusting for potential confounders including socio-demographic characteristics, war-related trauma exposure variables, anxiety and post-traumatic stress symptoms. In mediation analysis, depression symptoms mediated the associations between stressful war events and multiple risk behaviors.

Limitations

The psychometric properties of the questionnaires used in this study are not well established in war affected African samples thus ethno cultural variation may decrease the validity of our measures.

Conclusions

Adolescents with depression may be at a greater risk of increased engagement in multiple risk behaviors. Culturally sensitive and integrated interventions to treat and prevent depression among adolescents in post-conflict settings are urgently needed.  相似文献   
37.

Five years after the publication of DSM-5 in 2013, three widely used diagnostic instruments have published algorithms designed to represent its (sub-)criteria for Autism Spectrum Disorder (ASD) in children and adolescents. This study aimed to: (1) establish the content validity of these three DSM-5-adapted algorithms, and (2) identify problems with the operationalization of DSM-5 diagnostic criteria in measurable and observable behaviors. Algorithm items of the Autism Diagnostic Observation Schedule—Second Edition (ADOS-2), Developmental, Dimensional and Diagnostic Interview (3di) and Diagnostic Interview for Social and Communication Disorders—11th edition (DISCO-11) were mapped onto DSM-5 sub-criteria. The development and decision-making rules integrated in their algorithms were then compared with DSM-5. Results demonstrated significant variability in the number and nature of sub-criteria covered by the ADOS-2, 3di and DISCO-11. In addition to differences in the development of algorithms and cut-off scores, instruments also differed in the extent to which they follow DSM-5 decision-making rules for diagnostic classification. We conclude that such differences in interpretation of DSM-5 criteria provide a challenge for symptom operationalization which will be most effectively overcome by consensus, testing and reformulation.

  相似文献   
38.
Cholinergic neuronal loss in the pedunculopontine nucleus (PPN) associates with abnormal functions, including certain motor and nonmotor symptoms. This realization has led to low-frequency stimulation of the PPN for treating patients with Parkinson disease (PD) who are refractory to other treatment modalities. However, the molecular mechanisms underlying PPN neuronal loss and the therapeutic substrate for the clinical benefits following PPN stimulation remain poorly characterized, hampering progress toward designing more efficient therapies aimed at restoring the PPN''s normal functions during progressive parkinsonism. Here, we investigated postmortem pathological changes in the PPN of PD cases. Our study detected a loss of neurons producing gamma-aminobutyric acid (GABA) as their output and glycinergic neurons, along with the pronounced loss of cholinergic neurons. These losses were accompanied by altered somatic cell size that affected the remaining neurons of all neuronal subtypes studied here. Because studies showed that mitochondrial dysfunction exists in sporadic PD and in PD animal models, we investigated whether altered mitochondrial composition exists in the PPN. A significant up-regulation of several mitochondrial proteins was seen in GABAergic and glycinergic neurons; however, cholinergic neurons indicated down-regulation of the same proteins. Our findings suggest an imbalance in the activity of key neuronal subgroups of the PPN in PD, potentially because of abnormal inhibitory activity and altered cholinergic outflow.CME Accreditation Statement: This activity (“ASIP 2013 AJP CME Program in Pathogenesis”) has been planned and implemented in accordance with the Essential Areas and policies of the Accreditation Council for Continuing Medical Education (ACCME) through the joint sponsorship of the American Society for Clinical Pathology (ASCP) and the American Society for Investigative Pathology (ASIP). ASCP is accredited by the ACCME to provide continuing medical education for physicians.The ASCP designates this journal-based CME activity (“ASIP 2013 AJP CME Program in Pathogenesis”) for a maximum of 48 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.CME Disclosures: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.Patients with Parkinson disease (PD) present with a multitude of motor-related disabilities, including progressive resting tremor, rigidity, bradykinesia/akinesia, gait disturbances, and postural instability. In addition, it is recognized increasingly that various nonmotor functions are also left impaired, including mood, cognition, sleep, autonomic nervous system functions, and sensory functions.1 A neuropathological signature of PD is the progressive deterioration of dopamine-producing neurons in the substantia nigra pars compacta (SNpc).2 Although the precise cellular and molecular mechanisms underlying this neuronal death remain unknown, several reports implicate an underlying mitochondrial dysfunction, relating to energy deficits, enhanced production of free-radical species with concomitant oxidative stress,3 proteasomal deregulation,4 and neuronal excitotoxicity.5Evidence for a mitochondrial-related cause in PD stems from studies reporting on the use of human postmortem brains of patients with PD, which found a deficiency of complex I of the mitochondrial respiratory chain in the SNpc.6 Furthermore, outside the central nervous system a mitochondrial respiratory chain complex I deficiency has also been detected in the blood platelets of patients with PD, with some patients who also displayed defects of mitochondrial respiratory chain complexes II and III.7 In this regard, Gu et al8 found that a mitochondrial DNA (mtDNA) abnormality may underlie this mitochondrial defect in at least a proportion of patients with PD. By contrast, data reporting on mitochondrial respiratory chain defects in skeletal muscle cells of patients with PD remain somewhat more controversial. In this regard, Penn et al9 performed 31P magnetic resonance spectroscopy on the resting muscles of patients with PD, to report detecting defects in oxidative phosphorylation in the patients'' musculature, compared with healthy control cases. However, a study by Taylor et al10 was unable to validate this result. It has been proposed that the conflicting results that report on skeletal mitochondrial defects in patients with PD may relate to either methodological variation for assessing this biochemical defect or may be a reflection of the heterogeneity of the disease.11Further evidence for an association between PD and a mitochondrial defect was obtained from the use of experimental neurotoxins such as rotenone and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Use of such toxins mimic parkinsonism in animals to a remarkably accurate extent, with studies showing that the pathological substrate for this defect may be due to the ability of such toxins to inhibit complex I of the mitochondrial respiratory chain.12,13 Finally, disordered mitochondrial function, including defects in oxidative phosphorylation, are also seen in rare, young-onset genetic forms of PD, such as in patients who harbor mutations in genes such as Parkinson protein 2, E3 ubiquitin protein ligase [parkin (official symbol, PARK2)], parkinson protein 7 [DJ-1, (official symbol, PARK7)], and PTEN (phosphatase and tensin homologue) induced putative kinase 1 (PINK1), where loss of function of the respective protein products associate with deregulation of the mitochondrial quality control pathways of the cells.14Although the principal motor features of PD stem from reduced dopaminergic innervation of the striatum because of a substantial loss of SNpc dopaminergic neurons, recognition is growing that PD symptoms could result from disruption to multiple neural regions and systems.15 Although the loss of neurons is most conspicuous in the SNpc, neuronal loss and the presence of intracytoplasmic Lewy bodies (LBs) and Lewy neurites (LNs), composed of aggregation-prone proteins such as α-synuclein (αSYN) form an additional neuropathological hallmark of PD16 and have been observed in brain regions as diverse as the dorsal motor nucleus of vagus of the medulla, the locus ceruleus in the pons, the raphe nucleus, the basal forebrain, and allocortical regions such as the hippocampus and amygdala.17 Such widespread distribution of PD pathology could correlate with the variety of motor and nonmotor symptoms observed in patients with PD.18 PD-related pathologies that affect regions other than the dopaminergic-rich SNpc suggest that, although treatments that target only the nigrostriatal dopaminergic system could substantially benefit patients with PD, they are unlikely to completely resolve the PD-related deficit.19One particular brain region, the pedunculopontine nucleus (PPN), located within the lateral tegmental region and spanning the pontine midbrain isthmus, has been deemed critically important for regulating some of the physiological functions that fail during progressive PD. Such functions include regulating the activity of the reticular activating system for controlling rapid eye movement (REM) sleep.20 Interestingly, patients with PD frequently present with abnormal REM muscle tone and concomitant REM sleep behavior disorder (RBD),21 which may be due to a loss of PPN cells and their concomitant functions during progressive PD. Moreover, PPN axons project toward and receive input from a variety of brain regions, including the thalamus, SN (both the compacta and reticular part), cortical regions, and spinal cord, all of which are involved in regulating aspects of voluntary motor function.22–30 The PPN was assigned a role in the onset and progression of PD because of reports that the nucleus undergoes degenerative changes, principally affecting the resident cholinergic neurons.31,32 The loss of these cells is believed to provide the cellular basis for the gait and postural deficits that patients with PD experience33 and nonhuman primates rendered parkinsonian via cytotoxic lesions.34,35 In addition, LBs and LNs are seen within the remaining PPN neurons in the postmortem brains of patients with PD.36 Such findings provided the rationale for the commencement of therapeutic trials of deep brain stimulation of the PPN, with trial results reporting a reduction in gait and postural dysfunction in patients with PD after receiving PPN deep brain stimulation.37,38Here, we used serially cut sections taken from the postmortem PPN of patients with PD and compared this with elderly, healthy control persons, who died without known neurological or psychiatric deficit. After confirming a decreased number of cholinergic neurons in PD-affected PPNs, as previously reported,31,32 we studied whether the remaining cholinergic neurons undergo somatic cell size alterations. Because it is unknown whether other, noncholinergic neurons are also lost in the PPN of patients with PD, we next determined whether glycinergic and GABAergic neurons in the PPN also degenerate as a result of PD, and whether the remaining neurons undergo structural alterations. In an attempt to explain the altered cell numbers and cellular structural changes seen in the PPN of the present study''s cohort of patients with PD compared with controls, and consistent with the wide amount of literature that suggests an association between PD and mitochondrial dysfunction, we determined whether the loss of different neuronal subpopulations in the PPN is linked to mitochondrial abnormalities.  相似文献   
39.
neurogenetics - A de novo 0.95 Mb 8p21.3 deletion had been identified in an individual with non-syndromic autism spectrum disorder (ASD) through high-resolution copy number variant analysis....  相似文献   
40.
The advent of massive parallel sequencing is rapidly changing the strategies employed for the genetic diagnosis and research of rare diseases that involve a large number of genes. So far it is not clear whether these approaches perform significantly better than conventional single gene testing as requested by clinicians. The current yield of this traditional diagnostic approach depends on a complex of factors that include gene‐specific phenotype traits, and the relative frequency of the involvement of specific genes. To gauge the impact of the paradigm shift that is occurring in molecular diagnostics, we assessed traditional Sanger‐based sequencing (in 2011) and exome sequencing followed by targeted bioinformatics analysis (in 2012) for five different conditions that are highly heterogeneous, and for which our center provides molecular diagnosis. We find that exome sequencing has a much higher diagnostic yield than Sanger sequencing for deafness, blindness, mitochondrial disease, and movement disorders. For microsatellite‐stable colorectal cancer, this was low under both strategies. Even if all genes that could have been ordered by physicians had been tested, the larger number of genes captured by the exome would still have led to a clearly superior diagnostic yield at a fraction of the cost.  相似文献   
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