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James Williams

Publications and source records attributed to James Williams.

At least 19 recordsLinked to original sources
PubMed2026

Ventriculostomy-Related Infections by Country-Income Level: A Systematic Review and Bayesian Hierarchical Meta-analysis.

Our objective was to perform a systematic review and meta-analysis of published literature on ventriculostomy-related infection (VRI) and evaluate temporal and global trends. We conducted a systematic review and Bayesian hierarchical random-effects meta-analysis of VRI rates in adults, stratified by country-income level (high-income countries [HIC]; low- or middle-income countries [LMIC]), study design, sample size, enrollment period, VRI intervention, and VRI definition. We identified 159 articles published between 1989 and 2025 that included 523,704 patients with 7293 VRIs. The pooled VRI rate was 8.64% [95% CI: 7.44-9.97], with moderate heterogeneity and good model fit. The leave-one-out sensitivity analysis showed a mean absolute change of 0.06% and a maximum change of 0.2%, indicating robust analysis. Five of the 33 represented countries had VRI rates below the global pooled rate of 8.64%. Four were HICs: Singapore (VRI rate 3.3% [0.8-7]), the United States (VRI rate 4.6% [3.4-5.9]), Germany (VRI rate 6.1% [1.1-18.9]), Norway (8.3% [0.3-68.4]), with 1 LMIC: China (8.5% [5.4-12.4]). VRI was significantly higher in studies using definitions beyond CSF culture alone for VRI (+3.16% [0.11- 6.52]) and in those from Europe (+7.29% [4.62-10.10]) and the Western Pacific (+4.09% [1.55-6.98]). No other subgroup demonstrated significant differences. This Bayesian meta-analysis provides global estimates and factors associated with VRI. Standardization of VRI definitions is critical for future benchmarking of VRI rates.

Humans↗
PubMed2006

Role of prostanoids in the regulation of cerebral blood flow during normoxia and hypoxia in the fetal sheep.

The fetal cardiovascular responses to hypoxia include decreased peripheral blood flow and increased cerebral, cardiac, and adrenal blood flow. Prostanoids, metabolites of cyclooxygenase enzyme activity, have potent effects on vascular tone in both the adult and the fetus. To examine the role of prostanoids in the regulation of fetal cerebral blood flow (CBF) during acute hypoxic stress, eight near term fetal sheep were studied after infusing vehicle or diclofenac, a cyclooxygenase inhibitor, followed by a 30-min period of hypoxia (arterial Po(2) 12 Torr). In the control experiments, CBF, measured continuously with laser Doppler flowmetry, increased to 148% of baseline values (p < 0.01) and cerebral vascular resistance decreased to 70% of baseline values after 30 min of hypoxic stress. During diclofenac infusion, hypoxia resulted in a CBF increase to only 129% of baseline, a significant attenuation (p < 0.05), accompanied by decreased plasma prostanoid concentrations. Increases in mean arterial blood pressure during hypoxia were also attenuated by diclofenac infusion. Flow and pressure responses were not accompanied by changes in cerebral vascular resistance. These results indicate that prostanoids indirectly modulate fetal CBF responses to hypoxia, but that their effects are mediated through modulation of systemic rather than cerebral vascular tone.

Animals↗
PubMed2006

Treatment of renal allograft polyoma BK virus infection with leflunomide.

BACKGROUND: Polyoma BK virus produces an aggressively destructive nephropathy in approximately 3% to 8% of renal allografts, is associated with graft loss within one year in 35% to 67% of those infected and there is no therapy of proven efficacy. Leflunomide is an immune suppressive drug with anti viral activity in vitro and in animals. METHODS: We treated twenty-six patients with biopsy proven NK virus nephropathy (BKN) with either leflunomide alone (n=17) or leflunomide plus a course of cidofovir (n=9) and followed them for six to forty months. Leflunomide was dosed to a targeted blood level of active metabolite, A77 1726, of 50 microg/ml to 100 microg/ml (150 microM to 300 microM). Response to treatment was gauged by serial determinations of viral load in blood and urine (PCR), serum creatinine, and repeat allograft biopsy. RESULTS: In the 22 patients consistently sustaining the targeted blood levels of active drug, blood and urine viral load levels uniformly decreased over time (P<.001). Mean serum creatinine levels stabilized over the first six months of treatment, and with 12 months or more of follow-up in 16 patients the mean serum creatinine has not changed significantly from base line. Four patients who did not consistently have blood levels of active drug (A77 1726) above 40 microg/ml did not clear the virus until these levels were attained or cidofovir was added. CONCLUSIONS: Leflunomide inhibits Polyoma virus replication in vitro and closely monitored leflunomide therapy with specifically targeted blood levels appears to be a safe and effective treatment for Polyoma BK nephropathy.

Aniline Compounds↗
PubMed2006

Midterm outcome in 158 consecutive Gore TAG thoracic endoprostheses: single center experience.

BACKGROUND: Despite recent improvements in surgical technique, some patients with descending thoracic aortic pathologies are unable to undergo open surgical repair due to significant comorbidities and/or unfavorable thoracic aortic anatomy. Some of these patients might be able to tolerate a less invasive approach, such as endoluminal grafting. We reviewed our consecutive clinical experience with the Gore TAG endoprosthesis (W. L. Gore & Assoc, Flagstaff, AZ) for the endovascular exclusion of assorted descending thoracic aortic pathologies in higher surgical risk patients. METHODS: After obtaining institutional review board approval, 158 high surgical risk patients underwent attempted delivery of a Gore TAG thoracic endoprosthesis between February 2000 and July 2004. Indications for study enrollment were atherosclerotic aneurysm (n = 76), aortic dissection (n = 36), penetrating aortic ulcer (n = 15), contained rupture (n = 11), pseudoaneurysm (n = 10), traumatic aortic injury (n = 5), aortobronchial fistula (n = 4), and aortic coarctation (n = 1). RESULTS: The device was successfully delivered in 156 (98.7%) patients. Mean patient age was 72 +/- 12.1 years. Three (1.9%) patients developed transient paraparesis after graft deployment and 1 (0.6%) patient developed paraplegia. While postimplantation endoleaks were observed in 18 (11.5%) patients, only 12 patients required reintervention. Thirty-day mortality was 3.8% (6 of 156). Mean follow-up was 21.5 +/- 18.8 months, and the overall mortality was 17.3% (27 of 156). CONCLUSIONS: Endoluminal grafting of multiple types of descending thoracic aorta pathologies with the Gore TAG thoracic endoprosthesis is feasible and safe in higher surgical risk patients. Additional studies and long-term follow-up of these patients are warranted.

Aged↗
PubMed2006

Are penetrating aortic ulcers best treated using an endovascular approach?

BACKGROUND: Optimal treatment for penetrating aortic ulcers has yet to be determined. Although open surgical repair is an effective therapeutic option, less invasive alternatives such as endoluminal grafting are emerging as a potential adjunct for the treatment of penetrating aortic ulcers isolated to the descending thoracic aorta. We reviewed our cumulative experience with thoracic endografting for penetrating aortic ulcers of the descending thoracic aorta. METHODS: Between March 2003 and September 2005, 21 patients with penetrating aortic ulcers of the descending thoracic aorta were treated with Gore TAG thoracic endoluminal stent-grafts as part of a single-center investigational device exemption protocol. RESULTS: Mean patient age was 73 +/- 12 years, and 7 (33%) of 21 were men and 14 (67%) were women. Patients presented with both acute (<14 days; 16/21, 76.2%) and chronic symptoms (5/21, 23.8%). The endoluminal stent-graft was successfully delivered in all 21 patients. No endoleaks were detected at 30-days postprocedurally or in follow-up (mean follow-up, 14 +/- 18 months). The 30-day mortality was 0%, and overall mortality was 4.8% (1/21), which was unrelated to the endovascular intervention. CONCLUSIONS: Endovascular therapy for penetrating aortic ulcers of the descending thoracic aorta is safe and feasible. The number of patients diagnosed with penetrating aortic ulcers is expected to increase as improved imaging systems are becoming more commonplace. As a result, new and safer treatment paradigms will become even more important in the treatment of aortic diseases. Compared with historical surgical results, endovascular therapy for penetrating aortic ulcers of the descending thoracic aorta appears to have less operative mortality and is as equally effective as open surgical repair. Long-term surveillance and continued investigation are warranted.

Adult↗
PubMed2006

Endovascular approaches for complex forms of recurrent aortic coarctation.

PURPOSE: To review a single-center experience with endovascular treatment of recurrent aortic coarctation in adults. METHODS: Since 1998, 11 patients (9 men; mean age 48+/-15 years, range 16-63) with recurrent aortic coarctation following previous coarctation repair were referred to our institution for treatment. Clinical presentations included pseudoaneurysm (n=2), restenosis (n=3), pseudoaneurysm accompanied by restenosis (n=4), and rupture of a post-coarctation pseudoaneurysm (n=2). All patients were treated using an endovascular approach as part of a single-center investigational device exemption protocol. RESULTS: Endovascular interventions included Palmaz stent implantation (n=3), implantation of an endoluminal graft (n=2), or a combination of both treatments in 6 patients. Three patients underwent balloon angioplasty before stenting or endografting, and 2 patients had a carotid-subclavian bypass done before the endovascular repair. All repairs were technically and clinically successful. The median length of stay after repair was 2.0+/-2.3 days. In follow-up, 2 patients underwent a carotid-subclavian bypass for left upper extremity claudication. Two patients required reintervention owing to migration of the stent in 1 and an endoleak 2 years after the initial procedure in the other. CONCLUSION: Endovascular approaches to adult coarctation appear to be safe and effective. With the emergence of endoluminal grafts and the widespread availability of the Palmaz stent, endovascular repair offers an excellent alternative to open surgery for complex cases of recurrent coarctation. Additional studies are indicated to assess the long-term outcomes of these patients.

Adolescent↗
PubMed2006

Steatosis and hepatitis C in an Alaska Native/American Indian population.

OBJECTIVES: To determine the prevalence and characteristics of steatosis in Alaska Natives/American Indians (AN/AI) with chronic hepatitis C virus (HCV) infection. STUDY DESIGN: This outcomes study began in 1994, and 988 AN/AI have been enrolled, including 222 study patients with a positive HCV RNA who underwent liver biopsy. METHODS: Study patients were analyzed for sex, age at biopsy, estimated length of infection, body mass index (BMI), genotype, ethanol use, HCV RNA and alanine aminotransferase levels. A pathologist blinded to patient identity and clinical data reviewed all biopsy slides for histologic activity and fibrosis. RESULTS: Moderate to severe steatosis was found significantly more often in genotype 3 than in genotypes 1 and 2 (p = 0.008). On multivariate analysis, BMI > 30 and Ishak fibrosis score > or = 2 were significantly associated with steatosis (p = 0.0013 and 0.0002, respectively), but only genotype 3 was associated with presence of moderate to severe steatosis (p = 0.008). CONCLUSIONS: Our findings in a cohort of AN/AI are consistent with results of previous studies in other groups that steatosis is associated with fibrosis in HCV and infection with genotype 3 is associated with more severe steatosis.

Adult↗
PubMed2005

Ciclesonide, a novel inhaled steroid, does not affect hypothalamic-pituitary-adrenal axis function in patients with moderate-to-severe persistent asthma.

BACKGROUND: Inhaled corticosteroids (ICSs) reduce local airway inflammation, which is an underlying cause of asthma symptoms. However, potential systemic side effects associated with ICS use are a major concern for asthmatic patients. METHODS: Adult patients (n = 60; > or = 18 years of age) with moderate-to-severe asthma were randomized to receive 4 weeks of treatment with ciclesonide (CIC), 320 microg bid (CIC 640), CIC, 640 microg bid (CIC 1280), fluticasone propionate (FP), 440 microg bid (FP 880), FP 880 microg bid (FP 1760), or placebo (PBO) [all doses expressed as ex-actuator; comparable to ex-valve doses of 800 and 1,600 microg/d for CIC and 1,000 and 2,000 microg/d for FP, respectively]. RESULTS: After 29 days of treatment, CIC 640, CIC 1280, and FP 880 had no significant effect on the mean serum cortisol area under the curve for 0 to 24 h (AUC0-24h). FP 1760 produced a statistically significant suppression in mean serum cortisol AUC0-24h compared to PBO (p = 0.0009; 95% confidence interval [CI] -117.5 [corrected] to -32.1). Results obtained with cosyntropin stimulation revealed no statistically significant differences among the groups. The CIC 640 group demonstrated a significant increase compared to the PBO group in 24-h urinary cortisol levels from baseline at week 4 (p = 0.0224; 95% CI, 0.0023 to 0.0283), while the other treatment groups revealed no change in this parameter. The incidence of treatment-emergent adverse events was similar in all groups, and all adverse events were mild or moderate in severity. CONCLUSION: Treatment with moderate and high doses of CIC does not result in hypothalamic-pituitary-adrenal-axis suppression as compared with PBO.

Administration, Inhalation↗
PubMed2005

Endoluminal stent-graft stabilization for thoracic aortic dissection.

PURPOSE: To review our experience with thoracic endografting for type B aortic dissection using the TAG Endoprosthesis. METHODS: A retrospective analysis was performed of data collected prospectively from March 2000 to July 2004 under an investigational device exemption protocol for the TAG thoracic endograft. In this time period, 40 patients (29 women; mean age 67 years, range 39-91) were treated with this endograft for type B aortic dissection. RESULTS: Technical success was 95%. There was 1 (2.5%) perioperative death, and 1 (3%) endoleak was treated with an additional graft on postoperative day 2. Fifteen (38%) patients experienced postoperative complications, mainly renal or pulmonary, and 1 (3%) patient developed postoperative paraplegia that did not resolve. The 1-year survival was 85%. Follow-up computed tomography was available for 31 patients with an average 15-month follow-up. There was no significant change in size of the thoracic aorta in 22 patients; 8 aneurysmal segments were significantly reduced in size and 1 thoracic aortic aneurysm expanded. No thoracic aortic ruptures were seen in this series. CONCLUSIONS: These early results indicate type B thoracic aortic dissections can be treated with acceptable morbidity and mortality using endografts. Stent-graft repair of the thoracic aorta may decrease the incidence of thoracic aortic expansion and rupture.

Adult↗
PubMed2005

Surgical correction of ascending type a thoracic aortic dissection: simultaneous endoluminal exclusion of the arch and distal aorta.

PURPOSE: To describe repair of an ascending type A dissection combining an open ascending tube graft with simultaneous great vessel transposition and antegrade deployment of an endoluminal graft across the arch and into the descending thoracic aorta. CASE REPORT: A 50-year-old man was evaluated at an outside hospital and transferred to our service for treatment of an ascending aortic dissection with associated lower extremity ischemia. Imaging identified an aortic dissection extending from the aortic root to the aortic bifurcation and into the right common iliac artery. A hybrid procedure incorporating both open and endovascular techniques successfully repaired the dissection and aneurysm and restored blood flow to the extremity. CONCLUSIONS: Although less invasive procedures are sometimes appropriate for repair in the descending thoracic aorta, surgical correction of an ascending dissection and endoluminal exclusion of the arch and distal aorta may form the basis of future treatment strategies for complex aortic pathologies, possibly eliminating the need for hypothermic cardiac arrest.

Aortic Dissection↗
PubMed2004

Hepatitis C virus quasi-species dynamics predict progression of fibrosis after liver transplantation.

BACKGROUND: The dynamics of hepatitis C virus (HCV) quasi species in the E2 region may correlate with the course of infection after orthotopic liver transplantation (OLT). METHODS: Thirty-four patients who underwent transplantation for HCV-related cirrhosis were studied. Serum and liver samples were available before OLT and at 1 week, 4 months, and 1 year after OLT. Patients were divided into group 1 (Knodell/Ishak fibrosis stage [FS] at 1 year, <2) and group 2 (FS at 1 year, > or =2). Complexity was estimated by the number of bands in a single-strand conformational polymorphism assay, whereas diversity was measured by Shannon entropy (SE) and median mobility shift (MMS) values derived from the heteroduplex mobility assay. Diversity dynamics were measured at transmission (before OLT vs. 1 week after OLT) and after OLT (1 week after OLT vs. 1 year after OLT). RESULTS: Complexity was higher in group 1 patients than in group 2 patients before OLT (P<.02) and at 1 week after OLT (P<.04). Diversity decreased in group 1 at transmission, as measured by either SE (P<.01) or MMS (P<.04). However, diversity increased in this group after OLT, as measured by SE (P<.03) or MMS (P<.02). FS at 1 year after OLT correlated with transmission changes, as measured by SE (r=0.642, P<.0001) and MMS (r=0.443, P<.04), and with post-OLT changes (for SE: r=-0.583, P<.01; for MMS: r=-0.536, P<.01). CONCLUSIONS: HCV complexity and diversity in the E2 region correlated with the severity of recurrence of HCV infection after OLT. Increased diversity of quasi species at transmission correlated with a higher FS at 1 year. However, increased diversity of quasi species in the post-OLT period correlated with a lower FS at 1 year. The dynamics of HCV quasi species in patients who undergo transplantation are predictive of outcome.

5' Untranslated Regions↗
PubMed2004

Epidemiology and risk factors for hepatitis C in Alaska Natives.

Large cohorts of persons infected with hepatitis C virus (HCV) that include patients with multiple risk exposures and behaviors have been rarely reported. We herein describe a population-based cohort of 759 Alaska Natives (AN) with HCV who were recruited into a long-term follow-up study. History of injection drug use (IDU) was reported by 60.1% and blood transfusion by 14.0%. The most common genotype was 1a (42.0%), followed by 1b (20.3%), 2b (14.7%), 3a (14.3%), and 2a (7.8%). By multivariable analysis, risk exposures (blood transfusion vs. other; P < 0.01; odds ratio [OR], 2.87; 95% confidence interval [CI], 1.51-5.45) and year of infection (P < 0.01; OR, 3.47; 95% CI, 1.34-8.96) were significantly associated with HCV RNA-positivity. Having an RNA concentration >/=2 million copies/mL was associated with male gender (OR, 1.94) and genotype (P < 0.01 overall; 1a vs. 3a: OR, 1.92; 2b vs. 3a: OR, 3.17) by multivariable analysis. In conclusion, the two principal risk exposures for AN infected with HCV (IDU and blood transfusion) are the same as the overall U.S. population. Persons with a history of blood transfusion were more likely to be HCV RNA positive than those without such history. Higher RNA levels found in males may explain the more severe disease previously reported in this group.

Adult↗
PubMed2004

Hepatic steatosis in hepatitis C virus genotype 3 infection: does it correlate with body mass index, fibrosis, and HCV risk factors?

Hepatic steatosis is a recognized feature of hepatitis C viral infection, particularly in genotype 3. The demographics and the associations contributing to moderate to severe steatosis in genotype 3 are not very well studied. The aim of this study is to determine the demographics and association of steatosis with fibrosis, obesity, diabetes, lipid levels, and risk factors among patients with hepatitis C virus (HCV) genotype 3. Two hundred ninety-three consecutive HCV patients (genotype 1, n = 218; genotype 2, n = 43; genotype 3, n = 32) at our institution were studied retrospectively. Demographic information such as height, weight, genotype, risk factors, serum cholesterol and triglyceride, and liver biopsy was collected. Steatosis was graded using the Brunt classification. HCV genotype 3-infected patients were younger (P < 0.04) and had lower serum cholesterol levels (P < 0.02) compared to nongenotype 3 patients. Moderate to severe steatosis was more prevalent in HCV genotype 3 patients (P < 0.001) with intravenous drug abuse as a risk factor (P = 0.04). Genotype 3 was the independent predictor of steatosis in all patients. There was no statistical association between grade of steatosis and body mass index, fibrosis, necroinflammation, or hyperlipidemia when only HCV genotype 3 patients were included in the multivariate logistic model. Hepatic steatosis is a feature of genotype 3. Patients with HCV genotype 3 are younger and have lower serum cholesterol levels. Genotype 3 is the independent predictor for steatosis in HCV patients. HCV genotype 3 patients with moderate to severe steatosis are more likely to have intravenous drug use as a risk factor.

Arizona↗
PubMed2003

General Surgeons and trauma. A questionnaire survey of General Surgeons training in ATLS and involvement in the trauma team.

OBJECTIVE: To determine the level of training of General Surgeons in the UK in the Advanced Trauma Life Support (ATLS) course and their involvement with hospital trauma teams. METHODS: Postal questionnaire sent to General Surgical Consultants and Higher Surgical Trainees (HSTs). RESULTS: 58% of General Surgeons who responded had attended ATLS, but only 30% of those who had been Consultants for more than 10 years. Eighty-seven percent considered the course 'essential' or 'some value'. Sixty-one percent of hospitals represented had a trauma team. A Consultant General Surgeon was a member of the team in 50% and the General Surgical HST in 82%. CONCLUSION: ATLS has been widely accepted by General Surgical Trainees and recently appointed Consultants. The trauma team approach to resuscitation has yet to become fully established in the UK and there is limited input from Consultant General Surgeons.

Attitude of Health Personnel↗
PubMed2003

Comparison of different HCV viral load and genotyping assays.

BACKGROUND: We report an interlaboratory comparison of methods for the determination of hepatitis C virus (HCV) serum load and genotype between a recently, established molecular laboratory at the Alaska Native Medical Center (ANMC) and two independent laboratories using different assays. At ANMC, a Real-time quantitative RT-PCR amplification methodology (QPCR) has been developed in which HCV viral loads are determined by interpolation of QPCR results to those of standards calibrated to the World Health Organization (WHO) First International Standard for HCV. HCV genotype is subsequently determined by direct sequencing of the DNA fragment generated from the QPCR assay. OBJECTIVES AND STUDY DESIGN: The above methods were statistically compared to results obtained for the same patient sera by two independent laboratories using different commercially available viral load assays; Quantiplex HCV RNA (Bayer Diagnostics) and Amplicor HCV Monitor (v 2.0) (Roche Molecular Systems), as well as two different genotyping assays; restriction fragment length polymorphism (RFLP) and INNO-LiPA HCV II (Innogenetics). RESULTS: ANMC's Real-time QPCR HCV viral load results compared moderately well with those obtained by the Quantiplex HCV RNA method (R2=0.3813), and compared quite well with recent lot numbers of Amplicor HCV Monitor in which viral loads are derived in IU/ml (R2=0.6408), but compared poorly with earlier lot numbers of Amplicor HCV Monitor in which viral loads were derived in copies/ml (R2=0.0913). The ANMC direct sequencing method for genotype determination compared moderately to very well with both the RFLP (84-86%) and INNO-LiPA (85-97.5%) methods. CONCLUSIONS: These viral load comparisons highlight the discrepancies that may occur when patient HCV viral loads are monitored using different types of assays. Comparison of HCV genotype by different methods is more reliable statistically and important clinically for predicting probability of response to antiviral therapy. However, viral loads are important for monitoring response once therapy has begun.

Evaluation Studies as Topic↗
PubMed2003

Treatment of refractory BK virus-associated nephropathy with cidofovir.

BK virus-associated nephropathy (BKVN) has become recognized as an important cause of allograft dysfunction in renal transplant recipients and despite reduction in immunosuppression, 30-40% of recipients ultimately progress to allograft loss. Cidofovir is an antiviral agent that demonstrates in vitro activity against murine polyomavirus and has been proposed for treatment of BKVN in renal allograft recipients. We describe the clinical course, renal function, serial renal histology and urine and blood viral load measurements in two consecutive patients with refractory BKVN who were treated with low-dose cidofovir (0.25 mg/kg IV). In each case, renal dysfunction and BK viral load progressed despite reduced immunosuppression, and persistent BK virus infection was documented in serial renal allograft biopsy specimens. Administration of low-dose cidofovir was associated with clearance of BK virus DNA from blood and allograft, and stabilization of renal function in both patients, without significant toxicity. These preliminary data suggest that low-dose cidofovir may be tolerated, even among renal transplant recipients with significant renal dysfunction due to BKVN. Prospective, controlled trials are warranted to further define the optimal dose, toxicity and potential role of cidofovir in renal transplant recipients with BK virus nephropathy.

Adult↗