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11.
Myeloablative conditioning allogeneic hematopoietic cell transplantation (HCT) puts patients at greater risk for significant cognitive and quality of life decline compared with recipients of reduced-intensity conditioning or autologous HCT. Vorinostat, a histone deacetylase inhibitor, has been shown to have neuroprotective and neurorestorative effects in preclinical models of neurologic diseases. Thus, within the context of a myeloablative conditioning phase II clinical trial of vorinostat combined with tacrolimus and methotrexate for graft-versus-host disease prophylaxis, we conducted an ancillary study to evaluate feasibility of assessing associations between vorinostat and neurocognitive function and quality of life (ClinicalTrials.gov NCT02409134). Nine patients (mean age, 53 years; range, 36 to 66) underwent computerized neuropsychological testing (Cogstate) and completed surveys of mood (Patient Health Questionnaire-9), anxiety (General Anxiety Disorder-7), and quality of life (Functional Assessment of Cancer Therapy–General). Control cohorts from a separate concurrent longitudinal study (19 autologous and 18 allogeneic HCT patients, who matched the vorinostat patients on relevant medical and demographic variables) completed the same test battery. All allogeneic patients received busulfan-based myeloablative conditioning and were transplanted with HLA-matched unrelated donors. The total neurocognitive performance score of vorinostat patients did not change significantly across the study duration (ie, baseline, day 30, day 100, and day 160). Depression, anxiety, and quality of life also did not differ significantly across time. In univariate analyses (analysis of variance), vorinostat-treated patients showed no difference in neurocognitive function or quality of life compared with autologous and allogeneic control subjects. However, when medical variables were accounted for in a linear mixed effects regression model, the total neurocognitive performance of vorinostat-treated patients was comparable with autologous control subjects. Notably, autologous control subjects performed significantly better than allogeneic control subjects (estimate, .64; standard error, .23; P ≤ .01). Moreover, a smaller percentage of vorinostat-treated patients were classified as mildly, moderately, or severely impaired across neurocognitive domains as well as time points compared with both control cohorts. Thus, vorinostat may have neurorestorative or neuroprotective effects in the HCT setting. Accordingly, we recognize the need for a future, full-scale randomized controlled trial to further examine this hypothesis.  相似文献   
12.
Opioid receptors and their endogenous peptide ligands play important roles in neurotransmission and neuromodulation in response to addictive drugs such as heroin, cocaine, and alcohol. In an earlier study, we reported that variation in the genes encoding the kappa-opioid receptor (OPRK1) and its peptide ligand (PDYN) were associated with the risk for alcoholism. We continued our investigation of the role of the opioid system in alcohol dependence by analyzing the genes encoding the micro- and delta-opioid receptors and their peptide ligands. We analyzed 18 OPRM1 SNPs, 18 OPRD1 SNPs, 7 PENK SNPs, and 7 POMC SNPs in a sample of 1923 European Americans from 219 multiplex alcohol dependent families. Employing a family-based test of association, we found no evidence that these four genes were significantly associated with alcohol dependence. We also did not find association between these genes and illicit drug dependence. Secondary analyses employing the narrower phenotype of opioid dependence (83 affected individuals) demonstrated association with SNPs in PENK and POMC, but not in OPRM1 or OPRD1. Haplotype analyses provided further support for the association of PENK and POMC with opioid dependence. Therefore, our data provide no support for the idea that variations in OPRM1, OPRD1, PENK and POMC are associated with alcohol dependence or general illicit drug dependence, but variations in PENK and POMC appear to be associated with the narrower phenotype of opioid dependence in these families.  相似文献   
13.
Infections are a common complication of allogeneic bone marrow transplantation and the leading cause of transplantation-related mortality. It had been hypothesized that transplantation following nonmyeloablative preparative regimens would result in fewer infections by causing less mucosal injury, less graft-versus-host disease, and allowing earlier immune reconstitution. We have retrospectively reviewed the infectious complications of 65 consecutive patients with advanced hematologic malignancies who underwent bone marrow transplantation using a novel preparative regimen consisting of cyclophosphamide, thymic irradiation, and in vivo T-cell depletion. Cytomegalovirus (CMV) infection occurred in 52% of cases in which the donor or recipient had evidence of prior CMV exposure. Using a strategy of preemptive therapy and secondary prophylaxis with ganciclovir, no CMV disease occurred. Infections with gram-positive bacteria predominated over the first 100 days after bone marrow transplantation. Thereafter, the relative proportion of gram-negative infections increased without a significant increase in episodes of neutropenia. The rate of bacterial infections was not influenced by relapse of the underlying malignancy. Seven patients developed infections with Aspergillus species, which was the most common infectious cause of death in these patients. Infections with viruses other than CMV (n=10) and with protozoan organisms (n=2) also occurred. The use of HLA-mismatched donors, the occurrence of grade II-IV acute graft-versus-host disease, and treatment with corticosteroids did not influence the risk of CMV or bacterial or fungal infections in patients who underwent transplantation following this preparative regimen. Overall, the incidence and spectrum of infections in this series was similar to the reported incidence of infections following conventional myeloablative allogeneic stem cell transplantation. We conclude that a quantitative T-cell deficiency in these extensively T-cell depleted patients may be a risk factor for infection, even in the absence of graft-versus-host disease.  相似文献   
14.
Haemophilus influenzae is a commensal and opportunistic pathogen of the human airways. A number of surface molecules contribute to colonization of the airways by H. influenzae, such as adhesins, including structures found in the lipooligosaccharide (LOS). A human bronchiolar xenograft model was employed to investigate the host-bacterial interactions involved in the colonization of the airway by H. influenzae. Differential display was used to identify H. influenzae mRNA that reflect genes which were preferentially expressed in the xenograft compared to growth. Eleven mRNA fragments had consistent increased expression when the bacteria grew in xenografts. On sequencing these fragments, eight open reading frames were identified. Three of these had no match in the NCBI or the TIGR database, while an additional three were homologous to genes involved in heme or iron acquisition and utilization: two of the mRNAs encoded proteins homologous to enzymes involved in LOS biosynthesis: a heptosyl transferase (rfaF) involved in the synthesis of the LOS core and a ketodeoxyoctonate phosphate-dependent acyltransferase (htrB) that performs one of the late acylation reactions in lipid A synthesis. Inoculation of human bronchiolar xenografts revealed a significant reduction in colonization capacity by htrB mutants. In vitro, htrB mutants elicited lesser degrees of cytoskeletal rearrangement and less stimulation of host cell signaling with 16HBE14o(-) cells and decreased intracellular survival. These results implicate acylation of H. influenzae lipid A as playing a key role in the organisms' colonization of the normal airway.  相似文献   
15.
These practice parameters are an update of the previously-published recommendations regarding the indications for polysomnography and related procedures in the diagnosis of sleep disorders. Diagnostic categories include the following: sleep related breathing disorders, other respiratory disorders, narcolepsy, parasomnias, sleep related seizure disorders, restless legs syndrome, periodic limb movement sleep disorder, depression with insomnia, and circadian rhythm sleep disorders. Polysomnography is routinely indicated for the diagnosis of sleep related breathing disorders; for continuous positive airway pressure (CPAP) titration in patients with sleep related breathing disorders; for the assessment of treatment results in some cases; with a multiple sleep latency test in the evaluation of suspected narcolepsy; in evaluating sleep related behaviors that are violent or otherwise potentially injurious to the patient or others; and in certain atypical or unusual parasomnias. Polysomnography may be indicated in patients with neuromuscular disorders and sleep related symptoms; to assist in the diagnosis of paroxysmal arousals or other sleep disruptions thought to be seizure related; in a presumed parasomnia or sleep related seizure disorder that does not respond to conventional therapy; or when there is a strong clinical suspicion of periodic limb movement sleep disorder. Polysomnography is not routinely indicated to diagnose chronic lung disease; in cases of typical, uncomplicated, and noninjurious parasomnias when the diagnosis is clearly delineated; for patients with seizures who have no specific complaints consistent with a sleep disorder; to diagnose or treat restless legs syndrome; for the diagnosis of circadian rhythm sleep disorders; or to establish a diagnosis of depression.  相似文献   
16.
Screening for carriage of methicillin-resistant Staphylococcus aureus (MRSA) is fundamental to modern-day nosocomial infection control, both for epidemiologic investigation and day-to-day decisions on barrier isolation. Numerous microbiologic techniques have been advocated for screening for nasal carriage of MRSA, including the use of charcoal rather than rayon swabs, preincubation of swabs in Stuart's medium, preincubation of swabs in salt-containing trypticase soy broth (TSB), use of mannitol-salt agar (MSA), use of MSA containing oxacillin (MSA(Ox)), use of Mueller-Hinton agar containing oxacillin (MHA(Ox)), and the use of MSA containing lipovitellin with an oxacillin disk (MSAL(Ox)). We report a prospective clinical trial undertaken to test all of these methods concurrently. Patients at high risk for MRSA carriage were screened with eight consecutive nasal swabs (four standard rayon, four charcoal-coated rayon), which were processed by primary plating on MSA, MSA(Ox), MHA(Ox), and MSAL(Ox); Stuart's preincubation for 72 h followed by plating on the solid media; overnight enrichment in salt-containing TSB followed by plating; and Stuart's preincubation for 72 h followed by overnight enrichment in TSB and plating. All of the above methods were repeated with charcoal swabs. Each patient was screened by 32 culture methods. Forty-three (42%) of 102 patients studied were positive for MRSA by one or more methods. Among the four media evaluated with direct plating, MSAL(Ox) was 11 to 25% more sensitive for detecting MRSA (MSAL(Ox) versus MSA(Ox) or MHA(Ox) or MSA, each P < 0.01). Preincubation in Stuart's medium for 72 h did not enhance recovery of MRSA. Enrichment in salt-containing TSB further increased yield 9%. MSAL(Ox) also showed the best specificity, 93%. Charcoal swabs showed no advantage over standard rayon swabs. Our results suggest that the highest yield will be achieved by using standard rayon swabs that are enriched overnight in TSB with inoculation onto MSAL(Ox) medium. Direct inoculation of swabs onto MSAL(Ox) allows detection of 90% of MRSA carriers.  相似文献   
17.
An immunocytochemical study of dorsal root ganglia, spinal cord and medulla oblongata was performed with antisera against the c-jun proto-oncogene encoded protein. The c-JUN-like immunoreactivity was restricted to the cell nucleus. In the CNS of untreated rats a basal c-JUN-like immunoreactivity was present in the nuclei of two types of neurons: motor and autonomic. Labelled nuclei could be seen in many motoneurons of the ventral horn of the entire length of spinal cord and the lower medulla oblongata, as well as in the area of the nucleus hypoglossus, the dorsal motor nucleus of nucleus vagus, nucleus ambiguus, nucleus facialis, nucleus abducens and motor nucleus of nucleus trigeminus. Additionally, labelled nuclei were found in the preganglionic sympathetic and preganglionic parasympathetic cells of the nucleus intermediolateralis and nucleus intercalatus in the spinal cord. In the medulla oblongata we found a cluster of cells with c-JUN-like immunoreactivity in an area between the dorsomedial part of the oral nucleus spinalis trigeminalis and the lateral border of the knee of facial nerve. Additionally, a second cluster of c-JUN-like immunoreactivity cells was visible between the ventromedial part of the oral nucleus spinalis trigeminalis and the lateral border of the rostral nucleus facialis. Examination of the characteristics of all cell groups with a basal c-JUN-like immunoreactivity in the spinal cord and lower brainstem revealed an overlapping distribution with cholinergic cell groups. Basal c-JUN-like immunoreactivity was also seen in the dorsal root ganglion cells. We examined the factors which can effect the expression of the c-JUN protein. Maximal expression of c-JUN-like immunoreactivity was observed after electrical stimulation of primary afferents. Stimulation of sciatic nerve at a strength sufficient to recruit A delta- and C-fibres produced c-JUN-like immunoreactivity in many nuclei of the ipsilateral dorsal horn of the lumbar spinal cord. c-JUN-like immunoreactivity was first detectable at 30 min following the end of stimulation, reached a maximum after 1 h, remained unchanged for another 1 h and declined to the basal level after 16 h. The distribution of c-JUN-like immunoreactivity in the lumbar cord coincided with the region of termination of sciatic nociceptive afferents. Contralateral c-JUN-like immunoreactivity appeared after 4 h. After noxious mechanical stimulation of the plantar hindpaw c-JUN-like immunoreactivity occurred in the spinal area of termination of nociceptive afferents of the tibial nerve. Noxious stimulation did not provoke additional c-JUN-like immunoreactivity in dorsal root ganglia.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
18.
Plasma amyloid beta protein (Abeta42) levels and late onset Alzheimer's disease (LOAD) have been linked to the same region on chromosome 10q. The PLAU gene within this region encodes urokinase-type plasminogen activator, which converts plasminogen to plasmin. Abeta aggregates induce PLAU expression thereby increasing plasmin, which degrades both aggregated and non-aggregated forms of Abeta. We evaluated single nucleotide polymorphisms (SNPs) in PLAU for association with Abeta42 and LOAD. PLAU SNP compound genotypes composed of haplotype pairs showed significant association with AD in three independent case-control series. PLAU SNP haplotypes associated significantly with plasma Abeta42 in 10 extended LOAD families. One of the SNPs analyzed was a missense C/T polymorphism in exon 6 of PLAU (PLAU_1=rs2227564), which causes a proline to leucine change (P141L). We analyzed PLAU_1 for association with AD in six case-control series and 24 extended LOAD families. The CT and TT PLAU_1 genotypes showed association (P=0.05) with an overall estimated odds ratio of 1.2 (1.0-1.5). The CT and TT genotypes of PLAU_1 were also associated with significant age-dependent elevation of plasma Abeta42 in 24 extended LOAD families (P=0.0006). In knockout mice lacking the PLAU gene, plasma--but not brain--Abeta42 as well as Abeta40 was significantly elevated, also in an age-dependent manner. The PLAU_1 associations were independent of the associations we found among plasma Abeta42, LOAD and variants in the IDE or VR22 region. These results provide strong evidence that PLAU or a nearby gene is involved in the development of LOAD. PLAU_1 is a plausible pathogenic mutation that could act by increasing Abeta42, but additional biological experiments are required to show this definitively.  相似文献   
19.
Risk for late onset Alzheimer disease (LOAD) and plasma amyloid beta levels (Abeta42; encoded by APP), an intermediate phenotype for LOAD, show linkage to chromosome 10q. Several strong candidate genes (VR22, PLAU, IDE) lie within the 1-lod support interval for linkage. Others have independently identified haplotypes in the chromosome 10q region harboring IDE that show highly significant association with intermediate AD phenotypes and with risk for AD. To pursue these associations, we analyzed the same haplotypes for association with plasma Abeta42 in 24 extended LOAD families and for association with LOAD in two independent case-control series. One series (MCR, 188 age-matched case-control pairs) did not show association (p=0.64) with the six haplotypes in the 276-kb region spanning three genes (IDE, KNSL1, and HHEX) previously shown to associate with LOAD. The other series (MCJ, 109 age-matched case-control pairs) showed significant (p=0.003) association with these haplotypes. In the MCJ series, the H4 (odds ratio [OR]=5.1, p=0.003) and H2(H7) haplotypes (OR=0.60, p=0.04) had the same effects previously reported. In this series, the H8 haplotype (OR=2.7, p=0.098) also had an effect similar as in one previous case control series but not in others. In the extended families, the H8 haplotype was associated with significantly elevated plasma Abeta42 (p=0.02). In addition, the H5(H10) haplotype, which is associated with reduced risk for AD in the other study is associated with reduced plasma Abeta42 (p=0.007) in our family series. These results provide strong evidence for pathogenic variant(s) in the 276-kb region harboring IDE that influence intermediate AD phenotypes and risk for AD.  相似文献   
20.
A genome-wide scan was carried out on a segregating F2 population of rats derived from reciprocal intercrosses between two inbred strains of rats, Fisher 344 (F344) and Wistar Kyoto (WKY) that differ significantly in their behavioral coping responses to stress measured by the defensive burying (DB) test. The DB test measures differences in coping strategies by assaying an animals behavioral response to an immediate threat. We have previously identified three X-linked loci contributing to the phenotypic variance in behavioral coping. Here we report on six significant autosomal quantitative trait loci (QTL) related to different behaviors in the DB test:one for the number of shocks received, three for number of prod approaches, one for latency to bury, and one pleiotropic locus affecting both approach and latency. These QTL contributing to different aspects of coping behaviors show that the effect of genotype on phenotype is highly dependent on lineage. The WKY lineage was particularly influential, with five out of the six QTL affecting coping behavior only in rats of the WKY lineage, and one locus affecting only those in the F344 lineage. Thus, epigenetic factors, primarily of WKY origin, may significantly modulate the genetic contribution to variance in behavioral responses to stress in the DB test.  相似文献   
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