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S Schaller

Publications and source records attributed to S Schaller.

At least 37 records · Page 2Linked to original sources
PubMed2002

New technical developments in multislice CT, part 2: sub-millimeter 16-slice scanning and increased gantry rotation speed for cardiac imaging.

Despite all promising advances, some challenges remain for ECG-gated multislice CT examinations of the heart and the coronary arteries with current 4-slice detectors: adequate visualization of stents and severely calcified coronary arteries, examination of patients with higher heart rates and patients, who cannot adequately hold their breath for at least 30 sec. The new generation of multislice CT systems offering simultaneous acquisition of up to 16 sub-millimeter slices and gantry rotation times shorter than 0.5 sec has the potential to overcome these limitations. We describe the technical principles of cardiac scanning with a state-of-the-art 16-slice CT equipment (SOMATOM Sensation 16, Siemens AG, Forchheim, Germany). We discuss an extension of the Adaptive Cardio Volume (ACV) reconstruction approach for ECG-gated multislice spiral CT. We show the impact of reduced gantry rotation time (0.42 sec) on temporal resolution, and we demonstrate the influence of slice width on the visualization of stents and plaques. Deviating from general purpose applications a cone-correction is not required for cardiac scanning with 16-slice CT systems. In addition to the absolute improvement, the temporal resolution shows a different dependence on the patient's heart rate for 0.42 sec rotation time, reaching its optimum (105 msec) at 81 BPM. This has the potential to expand the range of heart rates accessible to routine clinical examinations. Owing to sub-millimeter slice width and optimized in-plane resolution characteristics, visualization of stents and severe calcifications in coronary arteries is significantly improved. Clinical experience will be needed to fully evaluate the potential of 16-slice technology for cardiac imaging.

Artifacts↗
PubMed2001

A human RNA polymerase II subunit is encoded by a recently generated multigene family.

BACKGROUND: The sequences encoding the yeast RNA polymerase II (RPB) subunits are single copy genes. RESULTS: While those characterized so far for the human (h) RPB are also unique, we show that hRPB subunit 11 (hRPB11) is encoded by a multigene family, mapping on chromosome 7 at loci p12, q11.23 and q22. We focused on two members of this family, hRPB11a and hRPB11b: the first encodes subunit hRPB11a, which represents the major RPB11 component of the mammalian RPB complex; the second generates polypeptides hRPB11balpha and hRPB11bbeta through differential splicing of its transcript and shares homologies with components of the hPMS2L multigene family related to genes involved in mismatch-repair functions (MMR). Both hRPB11a and b genes are transcribed in all human tissues tested. Using an inter-species complementation assay, we show that only hRPB11balpha is functional in yeast. In marked contrast, we found that the unique murine homolog of RPB11 gene maps on chromosome 5 (band G), and encodes a single polypeptide which is identical to subunit hRPB11a. CONCLUSIONS: The type hRPB11b gene appears to result from recent genomic recombination events in the evolution of primates, involving sequence elements related to the MMR apparatus.

Journal Article↗
PubMed2001

[Diagnosis of lung embolism with multislice spiral CT].

In recent years CT has been established as the method of choice for the diagnosis of central pulmonary embolism to the level of the segmental arteries. The key advantage of CT over competing modalities is the reliable detection of relevant alternative or additional disease causing the patient's symptoms. Although the clinical relevance of isolated peripheral emboli remains unclear, the alleged poor sensitivity of CT for the detection of such small clots has to date prevented the acceptance of CT as the gold standard for diagnosing pulmonary embolism. With the advent of multislice CT we can now cover the entire chest of a patient with 1-mm slices within one breath-hold. In comparison with thicker sections the detection rate of subsegmental emboli can be significantly increased with 1-mm sections. In addition the interobserver correlation which can be achieved with 1-mm sections by far exceeds the reproducibility of competing modalities. Meanwhile use of multislice CT for a combined diagnosis of pulmonary embolism and deep venous thrombosis with the same modality appears to be clinically accepted. In the vast majority of patients who receive a combined thoracic and venous multislice CT examination the scan either confirms the suspected diagnosis or reveals relevant alternative or additional disease. The therapeutic regimen is usually chosen based on the functional effect of embolic vascular occlusion. With the advent of fast CT scanning techniques, also functional parameters of lung perfusion can be non-invasively assessed by CT imaging. These advantages let multislice CT appear as an attractive modality for a non-invasive, fast, accurate and comprehensive diagnosis of pulmonary embolism, its causes, effects and differential diagnoses.

Humans↗
PubMed2001

Multi-slice computed tomography as a screening tool for colon cancer, lung cancer and coronary artery disease.

Recent promising trials that use low-dose CT for the early detection of lung cancer have reinvigorated the interest in screening approaches. At the same time the development of fast image acquisition techniques, such as multislice CT, have sparked renewed interest in cardiac imaging within the radiological community. In addition to special cardiac capabilities, multislice CT has several other features such as high acquisition speed and low-dose requirements that may make this modality a universal radiological screening tool. Non-invasive disease detection is the radiologist's domain. In this paper we identify criteria for effective screening and apply these criteria to screening approaches with multislice CT when used for detection of three disease entities: colon cancer; lung cancer; and cardiovascular disease.

Colonic Neoplasms↗
PubMed2001

Multi-slice CT for visualization of pulmonary embolism using perfusion weighted color maps.

PURPOSE: The purpose of our preliminary study was to evaluate the feasibility of a new technique for the perfusion weighted color display of the density of lung parenchyma derived from multi-slice CT (MSCT) data sets of clinical routine examinations for visualization of pulmonary embolism (PE). MATERIALS AND METHODS: Imaging of patients with suspected PE was performed on a commercially available MSCT (Somatom Volume Zoom; Siemens, Forchheim, Germany) after intravenous application of 120 cc of contrast-medium using a power injector. Scan parameters were 140 kV and 100 mAs, using a thin collimation of 4 x 1 mm and a table speed of 7 mm (pitch: 1.75). Derived from thin collimation axial slices (slice thicknesseff. 1.25 mm, reconstruction increment 0.8 mm), a new image processing technique was deployed. Based on these source images, an automated 3D-segmentation of the lungs was performed followed by threshold based extraction of major airways and vascular structures. The filtered volume data were color encoded and finally overlayed onto the original CT images. This color encoded display of parenchymal density distribution of the lungs was shown in axial, coronal and sagittal plane orientation. In four patients with excluded PE as well as in two patients with proven PE this new technique was performed. RESULTS: In the four patients that were considered negative regarding PE on MSCT, lung densitometry showed a homogeneous distribution of color encoded densities without circumscribed decreased or increased areas, beside the usually present gravity-dependent gradient in ventro-dorsal direction. In the two patients with proven PE, low density values on perfusion weighted color maps were found distally to the occluded pulmonary arteries. CONCLUSIONS: Our initial experience indicates that lung densitometry with an optimized display of the density distribution within the lung parenchyma may provide additional information in patients with suspected or proven PE. However, a comparison with ventilation/perfusion scintigraphy and a larger number of patients are necessary for the full clinical evaluation of this new functional imaging methodology.

Aged↗
PubMed2001

[Multi-slice spiral CT of the abdomen in oncological patients: influence of table support and detector configuration on image quality and radiation exposure].

PURPOSE: To evaluate the image quality and radiation exposure of different spiral CT scanning parameters for routine staging examination of the abdomen in oncologic patients using a multi-slice CT scanner. METHODS/MATERIALS: Examination of 40 patients in 4 groups on a multi-slice CT scanner (Somatom VolumeZoom, Siemens AG, Forchheim). Functional detector width (4 x 2.5, 4 x 5 mm) and pitch (table feed in relation to collimated slice width) were varied (3 and 5). Tube voltage (120 kV), effective tube current (160 mAs), slice-thickness (6 mm), increment (4 mm), kernel (B 30), and contrast injection parameters were kept constant. Axial images were assessed by three radiologists regarding delineation of anatomic structures, artifacts, and overall image quality. RESULTS: Significantly reduced image quality especially due to artifacts was observed using a 5 mm detector configuration with a pitch of 5 (scan time 9 sec). Image quality was rated best for a 2.5 mm detector configuration with a pitch of 3 and a scan time of 28 sec. The effective dose was independent of the pitch. However, the mean effective dose was 9% higher using the smaller detector configuration (9.9 mSv vs 10.9 mSv). CONCLUSIONS: For routine staging CT of the abdomen use of a 4 x 2.5 mm detector configuration with a pitch between 3 and 5 is recommended. A 4 x 5 mm detector configuration using overlapping data acquisition can also be recommended, but additional thin slice reformations are not possible.

Abdominal Neoplasms↗
PubMed2001

Individually adapted examination protocols for reduction of radiation exposure in chest CT.

RATIONALE AND OBJECTIVES: To develop a simple directive for the reduction of radiation exposure without loss of diagnostic information in routine chest CT examinations. METHODS: Two hundred fifty adult patients (164 male, 86 female) were entered into a prospective trial. All examinations were performed with a multislice CT technique (Somatom Volume Zoom, Siemens). Four groups of 50 patients each were scanned with patient-related specific parameters: individual mA-s values were derived from the estimated body weight: kilograms + 10, +/- 0, - 10, and - 20 mAs. The results were compared with those of 50 patients who were examined by a standard chest protocol by using the parameters 120 mAs and 140 kV. All other parameters including the tube voltage were kept constant. Subjective image quality was rated on a three-point scale: 1 = excellent, 2 = fair, 3 = nondiagnostic. In addition, objective criteria based on signal-to-noise measurements were assessed by using a region-of-interest methodology. RESULTS: Image quality was sufficient in all cases. Mean subjective gradings of image quality, based on soft-tissue window settings, were 1.1 for the 120-mAs protocol, 1.1 for the (body weight [kg] + 10) mAs protocol, 1.1 for the (body weight [kg] +/- 0) mAs protocol, 1.3 for the (body weight [kg] - 10) mAs protocol, and 1.2 for the (body weight [kg] - 20) mAs protocol. Objective criteria based on noise measurements showed mean +/- standard deviation values of 5.7 +/- 0.8 Hounsfield units (HU) for the 120-mAs protocol. For the reduced-dose protocols, values were calculated as 7.6 +/- 1.2 HU (group + 10), 7.9 +/- 1.3 HU (group +/- 0), 8.7 +/- 1.2 HU (group - 10), and finally 9.1 +/- 1.3 HU (group - 20). The best correlation for an entire subgroup was achieved with the - 10 protocol (body weight [kg] - 10) mAs, with nearly constant noise related to body weight in all patients. CONCLUSIONS: By deriving mAs values from body weight estimation, an individually adapted protocol for chest CT can be recommended and easily employed in a clinical setting. With an adaptation of the tube current-time product based on the estimated body weight of the patient - 10 (body weight [kg] - 10 mAs), a well-balanced examination without significant loss of information, even in soft-tissue window settings, can be performed with this particular scanner. For this adapted mAs protocol, a mean reduction of radiation exposure of 45% was achievable, compared with the standard protocol. A maximum decrease per case down to 31 mAs was obtained, without relevant loss of image quality. Therefore, for other types of CT scanners, analogous protocols may be adapted.

Adult↗
PubMed2001

Advanced single-slice rebinning for tilted spiral cone-beam CT.

Future medical CT scanners and today's micro CT scanners demand cone-beam reconstruction algorithms that are capable of reconstructing data acquired from a tilted spiral trajectory where the vector of rotation is not necessarily parallel to the vector of table increment. For the medical CT scanner this case of nonparallel object motion is met for nonzero gantry tilt: the table moves into a direction that is not perpendicular to the plane of rotation. Since this is not a special application of medical CT but rather a daily routine in head exams, there is a strong need for corresponding reconstruction algorithms. In contrast to medical CT, where the special case of nonperpendicular motion is used on purpose, micro CT scanners cannot avoid aberrations of the rotational axis and the table increment vector due to alignment problems. Especially for those micro CT scanners that have the lifting stage mounted on the rotation table (in contrast to setups where the lifting stage holds the rotation table), this kind of misalignment is equivalent to a gantry tilt. We therefore generalize the advanced single-slice rebinning algorithm (ASSR), which is considered a very promising approach for medical cone-beam reconstruction due to its high image quality and its high reconstruction speed [Med. Phys. 27, 754-772 (2000)], to the case of tilted gantries. We evaluate this extended ASSR approach (which we will denote as ASSR+, for convenience) in comparison to the original ASSR algorithm using simulated phantom data for reconstruction. For the case of nonparallel object motion ASSR+ shows significant improvements over ASSR, however, its computational complexity is slightly increased due to the broken symmetry of the spiral trajectory.

Algorithms↗
PubMed2001

Implementation of a cone-beam reconstruction algorithm for the single-circle source orbit with embedded misalignment correction using homogeneous coordinates.

We present an efficient implementation of an approximate cone-beam image reconstruction algorithm for application in tomography, which accounts for scanner mechanical misalignment. The implementation is based on the algorithm proposed by Feldkamp et al. and is directed at circular scan paths. The algorithm has been developed for the purpose of reconstructing volume data from projections acquired in an experimental x-ray micro-tomography (microCT) scanner. To mathematically model misalignment we use matrix notation with homogeneous coordinates to describe the scanner geometry, its misalignment, and the acquisition process. For convenience analysis is carried out for x-ray CT scanners, but it is applicable to any tomographic modality, where two-dimensional projection acquisition in cone beam geometry takes place, e.g., single photon emission computerized tomography. We derive an algorithm assuming misalignment errors to be small enough to weight and filter original projections and to embed compensation for misalignment in the backprojection. We verify the algorithm on simulations of virtual phantoms and scans of a physical multidisk (Defrise) phantom.

Algorithms↗
PubMed2000

Exact radon rebinning algorithm for the long object problem in helical cone-beam CT.

This paper addresses the long object problem in helical cone-beam computed tomography. We present the PHI-method, a new algorithm for the exact reconstruction of a region-of-interest (ROI) of a long object from axially truncated data extending only slightly beyond the ROI. The PHI-method is an extension of the Radon-method, published by Kudo, Noo, and Defrise in issue 43 of journal Physics in Medicine and Biology. The key novelty of the PHI-method is the introduction of a virtual object fpsi(x) for each value of the azimuthal angle psi in the image space, with each virtual object having the property of being equal to the true object f(x) in some ROI omegam. We show that, for each psi, one can calculate exact Radon data corresponding to the two-dimensional (2-D) parallel-beam projection of fpsi(x) onto the meridian plane of angle psi. Given an angular range of length pi of such parallel-beam projections, the ROI omegam can be exactly reconstructed because f(x) is identical to fpsi(x) in Omegam. Simulation results are given for both the Radon-method and the PHI-method indicating that 1) for the case of short objects, the Radon- and PHI-methods produce comparable image quality, 2) for the case of long objects, the PHI-method delivers the same image quality as in the short object case, while the Radon-method fails, and 3) the image quality produced by the PHI-method is similar for a large range of pitch values.

Algorithms↗
PubMed2000

Spiral interpolation algorithm for multislice spiral CT--part I: theory.

This paper presents the adaptive axial interpolator (AAI), a novel spiral interpolation approach for multislice spiral computed tomography (CT) implemented in a clinical multislice CT scanner, the SOMATOM Volume Zoom (Siemens Medical Systems, Forchheim, Germany). The method works on parallel-beam data generated from the acquired fan-beam data by azimuthal rebinning. Spiral interpolation is performed by distance-dependent weighting; i.e., for each ray, its distance to the image plane is evaluated and serves as an argument to a freely selectable weighting function, resulting in a weight factor. A normalization step is applied to the weight factors to ensure that the sum of all corresponding weights (i.e., the weights applied to rays that contribute to the same ray in the interpolated sinogram) is 1. By selection of appropriate weighting functions and suitable adjustment of the tube current, it is possible to keep the slice sensitivity profiles (SSP) as well as the pixel noise constant for all pitch values in the relevant range. Also, a large range of slice-thickness can be reconstructed from a given collimation. The method is, thus, very versatile. Further advantages are that it uses the entire applied dose for imaging and allows for efficient implementation using a table lookup approach.

Algorithms↗
PubMed2000

Spiral interpolation algorithms for multislice spiral CT--part II: measurement and evaluation of slice sensitivity profiles and noise at a clinical multislice system.

The recently introduced multislice data acquisition for computed tomography (CT) is based on multirow detector design, increased rotation speed, and advanced z-interpolation and z-filtering algorithms. We evaluated slice sensitivity profiles (SSPs) and noise of a clinical multislice spiral CT (MSCT) scanner with M = 4 simultaneously acquired slices and adaptive axial interpolator (AAI) reconstruction software. SSPs were measured with a small gold disk of 50 microm thickness and 2-mm diameter located at the center of rotation (COR) and 100 mm off center. The standard deviation of CT values within a 20-cm water phantom was used as a measure of image noise. With a detector slice collimation of S = 1.0 mm, we varied spiral pitch p from 0.25 to 2.0 in steps of 0.025. Nominal reconstructed slice thicknesses were 1.25, 1.5, and 2.0 mm. For all possible pitch values, we found the full-width at half maximum (FWHM) of the respective sensitivity profile at the COR equivalent to the selected nominal slice thickness. The profiles at 100 mm off center are broadened less than 7 % on the average compared with the FWHM at the COR. In addition, variation of the full-width at tenth maximum (FWTM) at the COR was below 10% for p < or = 1.75. Within this range, image noise varied less than 10% with respect to the mean noise level. The slight increase in measured slice-width above p = 1.75 for nominal slice-widths of 1.25 and 1.50 mm is accompanied by a decrease of noise according to the inverse square root relationship. The MSCT system that we scrutinized provides reconstructed slice-widths and image noise, which can be regarded as constant within a wide range of table speeds. With respect to this, MSCT is superior to single-slice spiral CT. These facts can be made use of when defining and optimizing clinical protocols: the spiral pitch can be selected almost freely, and scan protocols can follow the diagnostic requirements without technical restrictions. In summary, MSCT offers constant image quality while scan times are reduced drastically. Volume scans with three-dimensional (3-D) isotropic resolution are routinely feasible for complete anatomical regions.

Algorithms↗
PubMed2000

Single-slice rebinning reconstruction in spiral cone-beam computed tomography.

At the advent of multislice computed tomography ICT) a variety of approximate cone-beam algorithms have been proposed suited for reconstruction of small cone-angle CT data in a spiral mode of operation. The goal of this study is to identify a practical and efficient approximate cone-beam method, extend its potential for medical use, and demonstrate its performance at medium cone-angles required for area detector CT. We will investigate two different approximate single-slice rebinning algorithms for cone-beam CT: the multirow Fourier reconstruction (MFR) and an extension of the advanced single-slice rebinning method (ASSR), which combines the idea of ASSR with a z-filtering approach. Thus, both algorithms, MFR and ASSR, are formulated in the framework of z-filtering using optimized spiral interpolation algorithms. In each view, X-ray samples to be used for reconstruction are identified, which describe an approximation to a virtual reconstruction plane. The performance of approximate reconstruction should improve as the virtual reconstruction plane better fits the spiral focus path. The image quality of the respective reconstruction will be assessed with respect to image artifacts, spatial resolution, contrast resolution, and image noise. It turns out that the ASSR method using tilted reconstruction planes is a practical and efficient algorithm, providing image quality comparable to that of a single-row scanning system even with a 46-row detector at a table feed of 64 mm. Both algorithms tolerate any table feed below the maximum value associated to the detector height. Due to the z-filter approach, all detector data sampled can be used for image reconstruction.

Algorithms↗
PubMed2000

Advanced single-slice rebinning in cone-beam spiral CT.

To achieve higher volume coverage at improved z-resolution in computed tomography (CT), systems with a large number of detector rows are demanded. However, handling an increased number of detector rows, as compared to today's four-slice scanners, requires to accounting for the cone geometry of the beams. Many so-called cone-beam reconstruction algorithms have been proposed during the last decade. None met all the requirements of the medical spiral cone-beam CT in regard to the need for high image quality, low patient dose and low reconstruction times. We therefore propose an approximate cone-beam algorithm which uses virtual reconstruction planes tilted to optimally fit 180 degrees spiral segments, i.e., the advanced single-slice rebinning (ASSR) algorithm. Our algorithm is a modification of the single-slice rebinning algorithm proposed by Noo et al. [Phys. Med. Biol. 44, 561-570 (1999)] since we use tilted reconstruction slices instead of transaxial slices to approximate the spiral path. Theoretical considerations as well as the reconstruction of simulated phantom data in comparison to the gold standard 180 degrees LI (single-slice spiral CT) were carried out. Image artifacts, z-resolution as well as noise levels were evaluated for all simulated scanners. Even for a high number of detector rows the artifact level in the reconstructed images remains comparable to that of 180 degrees LI. Multiplanar reformations of the Defrise phantom show none of the typical cone-beam artifacts usually appearing when going to larger cone angles. Image noise as well as the shape of the respective slice sensitivity profiles are equivalent to the single-slice spiral reconstruction, z-resolution is slightly decreased. The ASSR has the potential to become a practical tool for medical spiral cone-beam CT. Its computational complexity lies in the order of standard single-slice CT and it allows to use available 2D backprojection hardware.

Algorithms↗
PubMed2000

Lamellar body membrane turnover is stimulated by secretagogues.

Lamellar bodies are specialized cellular organelles used for storage of surfactant by alveolar type II cells of the lung. We utilized monoclonal antibody (MAb) 3C9, which recognizes an integral lamellar body-limiting membrane protein of 180 kDa, to follow lamellar body trafficking. (125)I-labeled MAb 3C9 bound to the surface of type II cells and was internalized by the cells in a time- and concentration-dependent manner that was inhibitable by excess unlabeled antibody. The internalized antibody remained undegraded over a 4-h time period. The L2 rat lung cell line that does not have lamellar bodies did not bind iodinated 3C9. Exposure of type II cells to the secretagogues ATP, phorbol 12-myristate 13-acetate, and cAMP resulted in a 1.5- to 2-fold enhancement of binding and uptake of MAb 3C9. Calphostin C inhibited phorbol 12-myristate 13-acetate-stimulated phospholipid secretion and also reduced binding and uptake of MAb 3C9 by type II cells. Treatment of type II cells with phenylarsine oxide to obstruct clathrin-mediated endocytosis had no effect on the internalization of MAb 3C9 while markedly blocking the uptake of surfactant protein A and transferrin. An actin-mediated process was important for lamellar body membrane uptake because incubation with cytochalasin D partially inhibited MAb 3C9 incorporation by type II cells. These studies are compatible with enhanced lamellar body membrane turnover associated with surfactant secretion and indicate that this process can be monitored by the trafficking of the antigen reporter MAb 3C9.

Adenosine Triphosphate↗
PubMed1999

Interactions between the full complement of human RNA polymerase II subunits.

As an approach to elucidating the rules governing the assembly of human RNA polymerase II (hRPB), interactions between its subunits have been systematically analyzed. Eleven of the 12 expected hRPB subunits have previously been tested for reciprocal interactions (J. Biol. Chem. 272 (1997) 16815-16821). We now report the results obtained for the last subunit (hRPB4; Mol. Cell. Biol. 18 (1998) 1935-1945) and propose an essentially complete picture of the potential interactions occurring within hRPB. Finally, complementation experiments in yeast indicated that hRPB4 expression efficiently cured both heat and cold-sensitivity of RPB4-lacking strains, supporting the existence of conserved functional subunit interactions.

Animals↗
PubMed1999

Randomized, placebo-controlled trial of Chinese herb therapy for HIV-1-infected individuals.

CONTEXT: Alternative medicine or complementary remedies that have not been scientifically tested are nonetheless widely used to treat chronic illnesses, particularly if curative options are limited. OBJECTIVES: To assess the effectiveness of Chinese medicinal herbs in reducing symptoms and improving the quality of life of HIV-infected persons. DESIGN: Prospective, placebo-controlled double-blind study. SETTING: University-based HIV outpatient clinic. PATIENTS: 68 HIV-infected adults with CD4 cell counts <0.5 x 10(9)/L. INTERVENTION: Participants were randomized to receive four daily doses of seven pills containing a standardized preparation of 35 Chinese herbs or placebo for 6 months. MAIN OUTCOME MEASURES: Symptoms, HIV disease progression, HIV-1 RNA plasma viral loads, CD4 and CD8 cell counts, and scores on standard questionnaires for quality of life, depression, anxiety, and coping. RESULTS: Intervention and placebo groups were equivalent at baseline regarding, respectively, previous antiretroviral therapy (74% versus 79%), median CD4 cell counts (0.20 x 10(9)/L versus 0.25 x 10(9)/L), and median HIV-1 plasma viral loads (35,612 copies/ml versus 52,027 copies/ml). At enrollment, none of the study subjects was seriously ill or depressed, and average coping and quality of life scores were in the normal range. In all, 53 (78%) participants completed the study. Patients taking Chinese herbs reported significantly more gastrointestinal disturbances (79% versus 38%; p = .003) than those receiving placebo. No therapy-related toxicities were observed. At completion of the study, no significant differences between the intervention and placebo groups were found regarding plasma viral loads, CD4 cell counts, symptoms, and psychometric parameters. HIV-1 RNA level was unchanged at study end. Among participants who were not on concomitant antiretroviral therapy, median CD4 cell counts declined by 0.05 x 10(9)/L in both the intervention and placebo groups. CONCLUSIONS: This standardized formulation of Chinese herbs for HIV-infected individuals did not improve quality of life, clinical manifestations, plasma virus loads, or CD4 cell counts. The data suggest that this formulation of Chinese herbs is not effective when administered in a Western medicine setting.

Adult↗