Biomedical subjects

J S Jones

Publications and source records attributed to J S Jones.

At least 37 records · Page 2Linked to original sources

PubMed2000

Assessment of MEDLINE search strategies for randomized controlled trials in prosthodontics.

PURPOSE: The purpose of this study was to evaluate the sensitivity, specificity, and precision of MEDLINE search strategies for detecting randomized controlled trials (RCTs) in prosthodontics. MATERIALS AND METHODS: A list of RCTs was obtained by hand-searching the International Journal of Prosthodontics, Journal of Prosthetic Dentistry, and Journal of Prosthodontics published between 1988 and 1997. RCTs identified served as the "gold standard" with which different MEDLINE search strategies were compared. Subject headings, keywords, MEDLINE checktags, publication types, and combinations thereof were used, and their results were compared with the "gold standard". RESULTS: Sensitivity ranged from 9% to 67%, specificity was at least 96% for all searches, and precision ranged from 22% to 59%. The most productive searches were by publication type clinical trial and publication type randomized controlled trial. Combining search terms did not improve sensitivity for detecting RCTs published in prosthodontic journals (p > .10). CONCLUSION: These findings support the need for more detailed reporting of trial methodologies to facilitate accurate indexing of prosthodontic articles in MEDLINE.

Humans↗

PubMed2000

Dysregulation of the insulin/IGF binding protein-1 axis in transgenic mice is associated with hyperinsulinemia and glucose intolerance.

The insulin/IGF binding protein-1 (IGFBP-1) axis is important in coordinating insulin- and IGF-mediated regulation of glucose metabolism and glycemia. Dysregulation of the axis may play a role in the pathophysiology of disorders of insulin deficiency and resistance. We have investigated this hypothesis by generating transgenic mice that overexpress hIGFBP-1. To study the axis in its true physiological context, we used a human (h) IGFBP-1 cosmid clone so that transgene expression is responsive to normal hormonal stimuli. hIGFBP-1 mRNA is expressed in a tissue-specific fashion, and measurement of serum protein levels by specific immunoassay indicates normal physiological regulation in response to fasting/feeding and appropriate post-translational modification as indicated by the detection of phosphorylated and nonphosphorylated isoforms of the protein. The hypoglycemic response to exogenous IGF-I is attenuated in transgenic mice. Transgenic mice exhibit an enhanced insulin secretory response to a glucose challenge, although basal and stimulated blood glucose levels are similar to controls. There is a sexual dimorphism in phenotypic expression: male transgenic mice had higher stimulated glucose and insulin levels than did females. Transgenic mice exhibit fasting hyperglycemia and hyperinsulinemia and glucose intolerance in later life, indicating an age-related decline in glucocompetence. These findings demonstrate the importance of the normal inverse relationship between serum insulin and IGFBP-1 levels in glucoregulation and that sustained dysregulation of the insulin/IGF-I/IGFBP-1 axis is associated with impaired glucose tolerance and abnormalities of insulin action.

Aging↗

PubMed1999

Developing a register for randomized controlled trials in prosthodontics: results of a search from prosthodontic journals published in the United States.

STATEMENT OF PROBLEM: Treatment decisions are often made despite absence of evidence from well-conducted clinical trials. Conclusions about treatment efficacy derived from nonexperimental approaches often overestimate treatment effect. Randomized controlled trials (RCTs) provide the most reliable basis for evaluating effectiveness of treatment interventions. PURPOSE: This study attempted to identify and catalog RCTs in prosthodontic journals published in the United States as an initial step in creating a register of clinical trials that would be a resource in setting up systemic overviews of prosthodontic literature. METHODS: The International Journal of Prosthodontics, The Journal of Prosthetic Dentistry, and The Journal of Prosthodontics published between 1988 and 1997 were searched manually to identify clinical trials. Clinical trials had to meet the following criteria for inclusion in the register: the trial must involve human subjects, must include at least 2 treatment groups, and treatment group allocation must be randomized. RESULTS: A total of 3,631 articles in 196 journal issues were screened. Sixty-two articles (1.7%) met the minimum criteria for inclusion in the RCT register. CONCLUSION: Given the lack of randomized controlled trials in prosthodontic journals, a concerted effort by the organized prosthodontic community should be made to screen national and international journals and contribute to the development of a register of randomized controlled trials relevant to prosthodontics.

Dental Research↗

PubMed1999

Emergency department presentation of idiopathic intracranial hypertension.

Idiopathic intracranial hypertension (IIH), or pseudotumor cerebri, is a syndrome characterized by an elevated intracranial pressure in the absence of a focal lesion, infective process, or hydrocephalus. New onset IIH may present to the emergency department in a variety of ways. To describe the etiologic associations and clinical features in this disorder, we performed a retrospective analysis of consecutive emergency department patients with new onset IIH during the calendar years 1987-1996. A total of 52 patients met all study criteria. The mean patient age was 27+/-8.9 years; the female-to-male ratio was 7:1. An etiologic association could be identified in 85% of cases and included obesity, hypertension, drugs, endocrine, and systemic disorders. Headache was a dominant complaint in most patients (48/52) and associated with dizziness, nausea, and/or visual complaints. Fourteen patients (27%) were not diagnosed on their initial ED visit and were more likely to have atypical clinical features (71% vs. 24%; P = .004). Atypical features included paraesthesias, neck/back pain, unilateral headache, vertigo, and nystagmus. Papilledema, the ophthalmoscopic hallmark of IIH, was not detected initially in 11 patients (21%). These results suggest that IIH is a relatively uncommon neurological illness that may have a variety of causes. The emergency department diagnosis may be complicated by atypical clinical features and a lack of detectable papilledema.

Adolescent↗

PubMed1999

The effect of short stature, portal hypertension, and cholestasis on growth hormone resistance in children with liver disease.

Chronic liver disease is associated with GH resistance, which is characterized by high circulating GH and low insulin-like growth factor I (IGF-I) concentrations. Standard GH replacement has no effect on serum IGF-I in pediatric liver disease. The aims were to examine whether GH resistance can be overcome by supraphysiological GH and to determine whether GH resistance worsens with the progression of liver disease. Thirty children, divided into five groups whose liver disease was at clinically different stages, were studied. They were given 0.2 IU/kg x day GH for 4 days and then 0.4 IU/kg x day for the next 4 days. Serum IGF-I and binding proteins (IGFBPs) were measured by immunoassay. IGF-I was lower in all study groups than in normal controls. IGF-I, IGFBP-3, and acid-labile subunit rose in response to GH. The magnitude of the response reflected nutritional status and liver dysfunction; in particular, portal hypertension was associated with a poor IGF-I response. There was no change in IGFBP-2. GH resistance begins early in the natural history of childhood liver disease and develops with the progression of liver disease, particularly with portal hypertension. It may be partially overcome by supraphysiological GH administration, but the effect becomes smaller with worsening liver disease.

Body Height↗

PubMed1999