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61.
62.
Angela R. Perri Tatiana R. Feuerborn Laurent A. F. Frantz Greger Larson Ripan S. Malhi David J. Meltzer Kelsey E. Witt 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(6)
Advances in the isolation and sequencing of ancient DNA have begun to reveal the population histories of both people and dogs. Over the last 10,000 y, the genetic signatures of ancient dog remains have been linked with known human dispersals in regions such as the Arctic and the remote Pacific. It is suspected, however, that this relationship has a much deeper antiquity, and that the tandem movement of people and dogs may have begun soon after the domestication of the dog from a gray wolf ancestor in the late Pleistocene. Here, by comparing population genetic results of humans and dogs from Siberia, Beringia, and North America, we show that there is a close correlation in the movement and divergences of their respective lineages. This evidence places constraints on when and where dog domestication took place. Most significantly, it suggests that dogs were domesticated in Siberia by ∼23,000 y ago, possibly while both people and wolves were isolated during the harsh climate of the Last Glacial Maximum. Dogs then accompanied the first people into the Americas and traveled with them as humans rapidly dispersed into the continent beginning ∼15,000 y ago. 相似文献
63.
Meltzer E Guranda L Perelman M Krupsky M Vassilenko L Sidi Y 《European Journal of Internal Medicine》2005,16(8):615-617
We report a case where recurrent "pneumonia" was eventually diagnosed as lipoid pneumonia in an elderly patient with cerebrovascular disease. The discontinuation of paraffin oil laxative led to clinical improvement. Lipoid pneumonia, a foreign body-type reaction to the presence of lipid within lung parenchyma, is probably underdiagnosed and underreported, and paraffin oil laxative is the main causative agent. Paraffin oil is marketed as a food additive, and no information about its hazards is provided to clinicians or patients. We suggest that a change in paraffin oil licensing may decrease the incidence of lipoid pneumonia. 相似文献
64.
Kiren Kresa-Reahl Pavle Repovic Derrick Robertson Macaulay Okwuokenye Leslie Meltzer Jason P. Mendoza 《Clinical therapeutics》2018,40(12):2077-2087
Purpose
The goal of this study was to evaluate clinical outcomes and patient-reported outcomes (PROs) over 12 months in patients with relapsing multiple sclerosis (RMS) who switched from glatiramer acetate (GA) to delayed-release dimethyl fumarate (DMF) 240 mg BID after suboptimal response to GA in real-world clinical practice.Methods
The RESPOND (Effectiveness of DMF and Its Impact on PROs in Suboptimal GA Responders With RMS) study was a Phase IV, prospective, multicenter, open-label, single-arm, 12-month observational trial. The study was conducted in the United States at 63 sites between August 2013 and February 2016. Patients diagnosed with RMS who experienced a suboptimal response to GA (defined as perceived suboptimal efficacy, intolerance, or poor adherence to GA) were eligible for enrollment. DMF treatment was initiated within 60 days of enrollment. The primary objective was to estimate the annualized relapse rate (ARR) at 12 months based on data collected from medical records and compare it with the 12 months before DMF initiation. Secondary objectives of the study included assessing the change in PRO scores from baseline to 12 months; PROs were recorded before and at 6 and 12 months after DMF initiation.Findings
Of the 318 patients included in the analysis population, 247 (78%) completed treatment. Mean (SD) time on GA treatment before switching to DMF was 51.3 months (49.1 months). The ARR (95% CI) reported for the 12 months before DMF initiation was 0.49 (0.42–0.57) compared with 0.11 (0.07–0.17) at 12 months after DMF initiation, representing a 78% reduction in ARR (P < 0.0001). Statistically significant improvements from baseline were observed for multiple PROs, including the 36-item Short Form Health Survey physical and mental component summaries (P = 0.0201 and P = 0.0014, respectively), the 5-item Modified Fatigue Impact Scale (P = 0.0002), the 14-item Treatment Satisfaction Questionnaire for Medication (P < 0.0001), and the 7-item Beck Depression Inventory (P = 0.0117).Implications
DMF may be an effective treatment option in patients with RMS who experience a suboptimal response to GA. The results should be interpreted with caution due to the observational nature of the study and the lack of a control group. Other limitations of the study include a potential bias due to regression to the mean and lack of randomization. ClinicalTrials.gov identifier: NCT01903291. 相似文献65.
Myocardial perfusion imaging in humans by contrast echocardiography using polygelin colloid solution 总被引:1,自引:0,他引:1
T Santoso J Roelandt H Mansyoer N Abdurahman R S Meltzer P G Hugenholtz 《Journal of the American College of Cardiology》1985,6(3):612-620
This study evaluated the myocardial contrast effect and safety of polygelin colloid solution selectively injected into the coronary arteries in 25 patients during two-dimensional echocardiography. Six patients (group I) had selective intracoronary injections of nonagitated and 19 (group II) of hand-agitated polygelin colloid solution. Myocardial contrast was seen on two-dimensional echocardiographic cross sections in three patients of group I and in all patients of group II; in 16 patients it was also seen on M-mode echocardiograms. The contrast effect lasted for 15 to 60 seconds. The intensity of myocardial opacification was not significantly influenced by the amount of polygelin colloid solution injected, heart rate or cardiac size. The total number of contrast-enhanced segments after right and left coronary artery injections delineated the entire cross-sectional area in any given view. None of the patients developed symptoms during or immediately after the injections. One patient had transient second degree atrioventricular block after a right coronary wedge injection, one patient showed a QRS axis shift and two others had transient T wave changes. There were no aortic blood pressure changes and no significant serum enzyme (creatine kinase [CK], CK-MB fraction, glutamic oxaloacetic transaminase) elevation or alterations of left ventricular function assessed echocardiographically. It is concluded that hand-agitated polygelin colloid solution is a useful and safe intracoronary contrast agent for delineating myocardial perfusion areas on two-dimensional echocardiography in humans. 相似文献
66.
Infection of human gastrointestinal cells by HIV-1 总被引:11,自引:0,他引:11
M P Moyer R I Huot A Ramirez S Joe M S Meltzer H E Gendelman 《AIDS research and human retroviruses》1990,6(12):1409-1415
Human immunodeficiency virus (HIV-1) infected and replicated in primary cultures of normal human ileal and colonic epithelial cells. Monocyte-tropic strains (ADA, 24, and 36) were better able to replicate in the gastrointestinal (GI) cells than the T-cell-tropic HIV strain HTLV-IIIB. In some cultures, virus replication persisted through several months. Intestinal epithelium may be an initial target and reservoir for HIV and a vector for virus dissemination and transmission. 相似文献
67.
M S Meltzer M Nakamura B D Hansen J A Turpin D C Kalter H E Gendelman 《AIDS research and human retroviruses》1990,6(8):967-971
Although macrophages are major targets for human immunodeficiency virus (HIV) infection in vivo, study of HIV-macrophage interactions in vitro was hindered because many laboratory strains of HIV would not replicate in macrophages, and because survival of macrophages in culture was poor. Addition of purified macrophage colony-stimulating factor (M-CSF) to cultured macrophages markedly improves their survival, but does not induce proliferation. HIV isolates that replicate in macrophages will also replicate in lymphocytes; however, isolates adapted to lymphoid cells (such as HIV-HTLVIIIB) will not replicate in macrophages. The envelope gene appears to be a major determinant of the cell tropism of viral isolates. T-cell grown virus stocks synthesize abundant gp120, while virus grown in macrophages contains relatively much less gp120. Electron microscopy of virions from macrophages shows them to be depleted of gp120 surface "spikes." Recombination studies show that the portion of the genome coding for the envelope glycoprotein appears to determine cell tropism. Lastly, rsCD4 neutralized macrophage-tropic isolates less efficiently than T-cell tropic isolates. HIV replication in macrophages is partially under the control of cellular factors, although these have been less well characterized than they have in lymphocytes. 相似文献
68.
Coakley G; Mok CC; Hajeer AH; Ollier WE; Turner D; Sinnott PJ; Hutchinson IV; Panayi GS; Lanchbury JS 《Rheumatology (Oxford, England)》1998,37(9):988-991
OBJECTIVE: To examine whether promoter polymorphisms associated with
variation in interleukin-10 (IL-10) production are relevant to the
development of rheumatoid arthritis (RA) or Felty's syndrome (FS). METHODS:
DNA was obtained from 44 FS patients, 117 RA patients and 295 controls. The
promoter region between -533 and - 1120 was amplified by polymerase chain
reaction, and polymorphisms detected by restriction enzyme digest or
sequence-specific oligonucleotide probing. RESULTS: We found no significant
difference in allele or haplotype frequencies between the groups.
CONCLUSION: There is no association between FS or RA and these recently
identified IL-10 promoter polymorphisms. Other genetic or environmental
factors could explain the alterations in IL-10 levels seen in these
conditions.
相似文献
69.
R S Meltzer D Guthaner H Rakowski R L Popp R P Martin 《Heart (British Cardiac Society)》1979,42(3):261-265
Sixteen patients had two-dimensional echocardiographic diagnosis of the presence or absence of left ventricular thrombi and anatomical, radiological, or clinical confirmation of the diagnosis. Eleven patients had positive diagnoses, which were confirmed in 10 and possibly incorrect in one. Five other records were reviewed because the patients had undergone aneurysmectomy after two-dimensional echocardiograms: three were true negative and two were false negative studies. 相似文献
70.
F MAROTTA R BARRETO CC WU Y NAITO F GELOSA A LORENZETTI M YOSHIOKA E FESCE 《Journal of digestive diseases》2005,6(4):193-197
OBJECTIVE: The aim of this study was to test the effect of gut manipulation by either novel synbiotics or by metronidazole on either endotoxemia or the severity of liver damage in the course of acute pancreatitis from alcohol ingestion. METHODS: Sprague–Dawley rats were fed for 1 week through an intragastric tube a liquid diet with either: (i) 1 mL t.i.d. of a mixture of synbiotics (Lactobacillus acidophilus, Lactobacillus helveticus and Bifidobacterium in an enriched medium); (ii) 20 mg/kg t.i.d. metronidazole; or (iii) standard diet. Then, acute pancreatitis was induced by caerulein and when the disease was full‐blown, rats were fed an alcohol‐rich diet. Synbiotic and metronidazole treatment was given for a further 2 weeks. Transaminase and endotoxemia levels were measured before treatment, after 6 h, after 24 h and 2 weeks later, at the time the rats were killed. Liver samples were obtained for histological analysis. RESULTS: Synbiotics but not metronidazole improved the acute pancreatitis‐induced increase in endotoxemia and transaminase levels. The addition of alcohol worsened these variables to a limited extent in the synbiotic‐treated group, while metronidazole had a negative effect on liver damage. CONCLUSIONS: Gut flora pretreatment with synbiotics was able to effectively protect against endotoxin/bacterial translocation, as well as liver damage in the course of acute pancreatitis and concomitant heavy alcohol consumption. The beneficial effect of synbiotics on liver histology seems to be correlated with endotoxemia. Metronidazole did not produce such a beneficial effect; in fact, it further worsened liver damage when alcohol was added to the background of ongoing acute pancreatic inflammation. 相似文献