Doppler echocardiography does not accurately estimate pulmonary artery systolic pressure in HIV-infected patients

Doppler echocardiography is used to screen for HIV-related pulmonary arterial hypertension (HRPAH). We studied patients with HIV infection to determine the accuracy of Doppler echocardiography-estimated pulmonary artery systolic pressure (PASP) compared with PASP measured during right heart catheterization. Doppler echocardiography-estimated PASP was inaccurate in 19.7% of cases. Using Doppler echocardiography-estimated PASP, one in three patients with HRPAH was missed. Doppler echocardiography estimates of PASP are not accurate in patients with HIV.     

Effects of Age and Gender on Dynamic Stability During Stair Descent

Objective

To determine the effects of age and sex and their interaction effects on dynamic postural stability during stair descent.

Design

Cross sectional.

Setting

Laboratory.

Participants

Healthy younger adults (N=28) and healthy older adults (N=21).

Interventions

Not applicable.

Main Outcome Measures

Spatiotemporal gait parameters, displacement of center of mass (COM), instantaneous velocity of the COM, divergence between vertical projection of the COM, and center of pressure (COP).

Results

Interaction effects of age and sex were found in stride duration, COM displacement, and instantaneous velocity of the COM in the mediolateral direction. Older adults demonstrated longer stride duration with shorter double-limb stance and longer single-limb stance during stair descent. Women have significantly longer stride duration than men. The effects of sex and age were significant in the data normalized by height. Older adults and women demonstrated larger peak-to-peak COM displacement, peak instantaneous velocity of the COM, and COM-COP divergence than the younger individuals and men, respectively. Peak instantaneous velocity of the COM was significant different in most pairwise comparisons, but the COM-COP divergence was significantly different in several comparisons.

Conclusions

This study examined the COM and COP parameters to quantify dynamic stability during stair descent across sex and age. Although older women descended stairs successfully, they demonstrated differences in control of instantaneous velocity of the COM compared with the other participants. Dynamic instability could be detected by examining the control of instantaneous velocity of the COM. In developing a better understanding of the balance control of stair descent in healthy older adults, aging patients with various pathologies can be better assessed, appropriately treated, and provided with proper assistive devices.     

Preparation and partial characterization of a pancreatic cancer-associated glycoprotein expressing CA50.

In our previous study, two antigens associated with pancreatic cancer were prepared from ascites of the patients by using a newly developed affinity chromatography technique; one expressed CA19-9, CA50, Span-1, sialyl SSEA-1, and Dupan-2. This report describes the other part of the antigens, which was scarcely found in normal sera. This antigen was a glycoprotein with a high molecular weight of 1,000,000 in its native state, estimated by size exclusion chromatography on Sephacryl S400. After sodium dodecyl sulfate polyacrylamide gel electrophoresis and blotting analysis, the antigenic activity was observed on the 200-Kd band, and monoclonal antibody of CA50 showed intense reactivity to it. By means of an enzyme immunoassay, CA19-9 determinant was also recognized on it to a lesser extent, although sialyl SSEA-1 and Dupan-2 determinants were scarcely observed. From these observations, the present antigen was considered to be a serum glycoprotein carrying type-1 polylactosamine determinant and differs from previously reported glycoprotein carrying CA19-9 in its insolubility in perchloric acid solution because of its lesser degree of glycosilation. Serum levels of the antigen measured by enzyme-linked immunosorbent assay demonstrated that highly positive rates were observed in 78% of pancreatic cancers, 82% of biliary tract cancers, and 96% of hepatocellular carcinomas.     

Diastolic Dysfunction in Individuals With Human Immunodeficiency Virus Infection: Literature Review,Rationale and Design of the Characterizing Heart Function on Antiretroviral Therapy (CHART) Study

Antiretroviral therapy (ART) has been associated with a shift in the epidemiology of human immunodeficiency virus (HIV)–associated cardiomyopathy from a phenotype of primarily left ventricular (LV) systolic dysfunction to LV diastolic dysfunction (DD). Patients with HIV receiving ART have higher rates of DD compared with age-matched control subjects and develop DD at a younger age. However, little is known about the natural history and pathogenesis of DD in virally suppressed HIV-infected patients. Current evidence suggests that immune processes modulate the risk for cardiac involvement in HIV-infected persons. Ongoing inflammation appears to have myocardial effects, and accelerated myocardial fibrosis appears to be a key mediator of HIV-induced DD. The Characterizing Heart Function on Antiretroviral Therapy (CHART) study aims to systematically investigate determinants, mechanisms, and consequences of DD in HIV-infected patients. We will compare ART-treated virally suppressed HIV-infected individuals with and without DD and HIV? individuals with DD regarding (1) systemic inflammation, myocardial stress, and subclinical myocardial necrosis as indicated by circulating biomarkers; (2) immune system activation as indicated by cell surface receptors; (3) myocardial fibrosis according to cardiac magnetic resonance examination; (4) markers of fibrosis and remodeling, oxidative stress, and hypercoagulability; (5) left atrial function according to echocardiographic examination; (6) myocardial stress and subclinical necrosis as indicated by circulating biomarkers; (7) proteomic and metabolic profiles; and (8) phenotype signatures derived from clinical, biomarker, and imaging data.     

Malignant transformation in 1458 patients with potentially malignant oral mucosal disorders: a follow-up study based in a Taiwanese hospital

BACKGROUND: It is generally accepted that the development of cancer in the oral mucosa is preceded by an identifiable non-invasive precursor lesion. The aim of this follow-up study was to estimate the rate and the time to transformation in a group of patients from southern Taiwan with potentially malignant oral epithelial lesions. METHODS: The follow-up time is defined as the duration between the onset of the initial diagnosis and the occurrence of confirmed oral cancer. A total of 1458 patients with histological diagnoses of various pre-malignant oral lesions were followed up between 1991 and 2001. The average age at initial diagnosis was 47.5 years. The histological diagnoses were divided into six categories: epithelial dysplasia with hyperkeratosis/epithelial hyperplasia (8.85%); epithelial dysplasia with submucous fibrosis (2.54%); submucous fibrosis (27.57%); hyperkeratosis/epithelial hyperplasia (29.01%); lichen planus (9.80%) and verrucous hyperplasia (22.22%). RESULTS: Within the cohort of 1458 patients, 44 patients progressed to oral cancer in the same site as the initial lesions with an overall transformation rate of 3.02% and a mean follow-up time of 42.64 months. Eight of the 166 patients with dysplastic lesions and 15 of 423 patients with hyperkeratosis/epithelial hyperplasia progressed to malignancy. The other patients with malignant transformation originated from various pre-cancerous oral lesions and conditions (submucous fibrosis, eight of 402; lichen planus, three of 143; verrucous hyperplasia, 10 of 324). CONCLUSION: These results indicate that patients with pre-malignant oral lesions need long-term follow up.     

Artesunate: Investigational Drug for the Treatment of Severe Falciparum Malaria in Hawai‘i

Introduction

There are hundreds of millions of cases of malaria each year worldwide resulting in a million deaths. These deaths are mostly due to Plasmodium falciparum. The only Federal Drug Administration approved treatment for severe malaria is intravenous quinidine gluconate. Intravenous quinidine is increasingly unavailable in the United States. In 2007, the Center for Disease Control and Prevention implemented an investigational new drug protocol to allow the use of intravenous artesunate for cases of severe malaria in the United States. The authors present such a case treated under this protocol at Tripler Army Medical Center, Hawai‘i.

Case Report

A 49-year-old man presented to Tripler Army Medical Center, Hawai‘i in February 2009 with a one-month history of fever, chills, and weight loss. He recently travelled to multiple malaria endemic areas. Physical examination was significant for fever and prostration. Laboratory studies revealed anemia, thrombocytopenia, and a high parasite load of Plasmodium falciparum. A strategic network was activated to obtain and administer intravenous artesunate. His condition rapidly improved as his parasitemia cleared. He was discharged after six days with no adverse medication effects and full recovery upon six-month follow-up.

Discussion

Our patient met the criteria for severe Plasmodium falciparum malaria. He was immediately treated with intravenous artesunate and manifested a quick and durable response to therapy. At present, intravenous artesunate is awaiting Federal Drug Administration approval but available via a strategic network controlled by the Centers for Disease Control and Prevention. This case highlights a common delay in diagnosis, importance of optimal prophylaxis, and attention to travel history as they relate to the development of severe malaria.     

Biomechanics during exercise with a novel stairclimber

The current study aimed to investigate the stair-climbing biomechanics related to the lower extremities when subjects used the novel designed stair-climber, which could provide opportunity for both sagittal and frontal movements. 12 volunteers were required to step while either keeping the trunk static (STATIC) or allowing the trunk to shift with weight bearing (SHIFT). A motion analysis system and the 6-axis force and torque sensor embedded in the pedal were used to collect data. Foot contact forces and joint moments were calculated to represent loading characteristics. The joint angle and corresponding moments at the terminal point of the stance phase were computed to serve as the indicator of safety. Significant differences were found in peak foot contact forces, knee extensor moment, and hip abductor moment. At the end of the stance phase, various directions of moment between conditions were found in the knee and the ankle. The knee valgus angle, hip abductor moment, and knee extensor moment were significantly greater in SHIFT than in STATIC. The various stepping strategies caused differences in joint loading characteristics; therefore, these findings need to be given greater consideration in the design of training protocols.