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P R Cheney

Publications and source records attributed to P R Cheney.

10 recordsLinked to original sources

Biochemical evidence for a novel low molecular weight 2-5A-dependent RNase L in chronic fatigue syndrome.

Previous studies from this laboratory have demonstrated a statistically significant dysregulation in several key components of the 2',5'-oligoadenylate (2-5A) synthetase/RNase L and PKR antiviral pathways in chronic fatigue syndrome (CFS) (Suhadolnik et al. Clin Infect Dis 18, S96-104, 1994; Suhadolnik et al. In Vivo 8, 599-604, 1994). Two methodologies have been developed to further examine the upregulated RNase L activity in CFS. First, photoaffinity labeling of extracts of peripheral blood mononuclear cells (PBMC) with the azido 2-5A photoaffinity probe, [32P]pApAp(8-azidoA), followed by immunoprecipitation with a polyclonal antibody against recombinant, human 80-kDa RNase L and analysis under denaturing conditions. A subset of individuals with CFS was identified with only one 2-5A binding protein at 37 kDa, whereas in extracts of PBMC from a second subset of CFS PBMC and from healthy controls, photolabeled/immunoreactive 2-5A binding proteins were detected at 80, 42, and 37 kDa. Second, analytic gel permeation HPLC was completed under native conditions. Extracts of healthy control PBMC revealed 2-5A binding and 2-5A-dependent RNase L enzyme activity at 80 and 42 kDa as determined by hydrolysis of poly(U)-3'-[32P]pCp. A subset of CFS PBMC contained 2-5A binding proteins with 2-5A-dependent RNase L enzyme activity at 80, 42, and 30 kDa. However, a second subset of CFS PBMC contained 2-5A binding and 2-5A-dependent RNase L enzyme activity only at 30 kDa. Evidence is provided indicating that the RNase L enzyme dysfunction in CFS is more complex than previously reported.

2',5'-Oligoadenylate Synthetase↗

Primary juvenile fibromyalgia syndrome and chronic fatigue syndrome in adolescents.

Chronic fatigue syndrome (CFS) and primary juvenile fibromyalgia syndrome (PJFS) are illnesses with a similar pattern of symptoms of unknown etiology. Twenty-seven children for whom CFS was diagnosed were evaluated for fibromyalgia by the presence of widespread pain and multiple tender points. Eight children (29.6%) fulfilled criteria for fibromyalgia. Those children who met fibromyalgia criteria had a statistically greater degree of subjective muscle pain, sleep disturbance, and neurological symptoms than did those who did not meet the fibromyalgia criteria. There was no statistical difference between groups in degree of fatigue, headache, sore throat, abdominal pain, depression, lymph node pain, concentration difficulty, eye pain, and joint pain. CFS in children and PJFS appear to be overlapping clinical entities and may be indistinguishable by current diagnostic criteria.

Adolescent↗

Retroviral sequences related to human T-lymphotropic virus type II in patients with chronic fatigue immune dysfunction syndrome.

Chronic fatigue immune dysfunction syndrome (CFIDS) is a recently recognized illness characterized by debilitating fatigue as well as immunological and neurological abnormalities [Straus, S.E. (1988) J. Inf. Dis. 157, 405-412]. Once thought to be caused by Epstein-Barr virus, it is now thought to have a different but unknown etiology. We evaluated 30 adult and pediatric CFIDS patients from six eastern states for the presence of human T-lymphotropic virus (HTLV) types I and II by Western immunoblotting, polymearse chain reaction, and in situ hybridization of blood samples. The majority of patients were positive for HTLV antibodies by Western blotting and for HTLV-II gag sequences by polymerase chain reaction and in situ hybridization. Twenty nonexposure healthy controls were negative in all assays. These data support an association between an HTLV-II-like virus and CFIDS.

Adolescent↗

The effect of pH buffering on reducing the pain associated with subcutaneous infiltration of bupivicaine.

The authors propose that pH buffering of bupivicaine with sodium bicarbonate reduces the pain associated with its local subcutaneous infiltration. In a double-blind, prospective study, 62 healthy adult volunteers received a 0.5 mL subcutaneous infiltration of 0.5% buffered bupivicaine into the dorsum of a randomly chosen hand. The pH was adjusted to 7.0 by adding 0.05 mL of sodium bicarbonate (1 mEq/L [corrected]) to 10 mL vials of commercially available bupivicaine (1:200 dilution). The control hand was injected with the same amount of unbuffered agent. Pain was scored after each infiltration using a nonsegmented visual analogue scale. Student's t-test for paired measurements was used to analyze intergroup pain score differences. Forty-three subjects (69%) reported less pain with buffered bupivicaine and only 17 (27%) noted a modest increase: two subjects (3%) reported no difference. The mean pain score for the buffered agent was 22 mm compared with 30 mm for the control. The mean difference (control-experimental) was 8 mm (t = 4.64, df = 61, P less than .001). The authors conclude that the addition of sodium bicarbonate to bupivicaine reduces the pain associated with its local infiltration.

Adult↗

Rapid visual colorimetry of peritoneal lavage fluid.

STUDY HYPOTHESIS: That visual colorimetry can be used to rapidly and precisely estimate the erythrocyte count of 1:5 dilutions of simulated peritoneal lavage fluid. POPULATION: Fifty-four normal adult human subjects. METHODS: The automated or chamber RBC count is often used on fluid obtained by peritoneal lavage in patients with abdominal trauma to help determine the need for surgery. Unfortunately, this method sometimes results in excessive delay. We designed and built a simple colorimeter that facilitated rapid direct visual comparison of unknown samples with known color standards. A radiograph view box was used as a light source. Standards were prepared in 16-mm glass tubes to simulate peritoneal lavage fluid with RBC counts ranging from 0 to 140,000 in 10,000 cell/microL increments; 1:5 dilutions with water were used throughout to reduce opacity. Thimerosal was added to unknowns and standards to stabilize color; all samples were kept refrigerated at 4 C when not in use. In a double-blind in-vitro study, each subject matched 20 randomly distributed unknowns ranging from 12,000 to 131,000 erythrocytes/microL to the nearest standard. RESULTS: The mean absolute error for all 1,080 determinations was 3,560 RBC/microL (95% CI = 4,290-4,830; SD = 4,560; t = 39.6; df = 1,079; P less than .001). This method correctly predicted the RBC count to within 9,000 cells/microL 95% of the time. CONCLUSION: Visual comparison of 1:5 dilutions of simulated peritoneal lavage fluid with known color standards can be used to rapidly and precisely estimate the erythrocyte count.

Abdominal Injuries↗