Comparative Effectiveness of Two Models of Point-of-Care Ultrasound for Detection of Post-Void Residual Urine during Acute Ischemic Stroke: Preliminary Findings of Real-World Clinical Application

We conducted a comparative study of two models of point-of-care ultrasound devices for measuring post-void residual urine (PVRU). We prospectively enrolled 55 stroke inpatients who underwent both real-time B-mode ultrasound (Device A) and automated three-dimensional (3D) scanning ultrasound (Device B), with a total of 108 measurements. The median PVRU volume of Device B was 40 mL larger than that of Device A. The PVRU difference between the devices was positively and linearly correlated with PVRU. The correlation of PVRU volume between the devices was strong, but the agreement level was only moderate. Measurement deviations were observed in 43 (40%) and 11 (10%) measurements with Device B and Device A, respectively. The PVRU volume was low in spherical bladder shapes but sequentially increased in triangular, undefined, ellipsoid, and cuboid bladder shapes. Further comparison of 60 sets of PVRU without measurement deviations revealed higher agreements between the devices at correction coefficients of 0.52, 0.66, and 0.81 for PVRU volumes of <100, 100-200, and >200 mL, respectively. The automated 3D scanning ultrasound is more convenient for learning and scanning, but it exhibits larger measurement deviations. Real-time B-mode ultrasound accurately visualizes the urinary bladder but tends to underestimate the urinary bladder when the PVRU volume is large. Hence, real-time B-mode ultrasound with automated PVRU-based adjustment of calculation formulas may be a better solution for estimating bladder volume.

Photophysical properties and singlet oxygen generation ofmeso-iodinated free-base corroles

In order to study the effect of meso-iodination of free-base corroles on their photophysical character, we designed and synthesized a series of free-base corrole derivatives F10–OH (iodine-free), F10–OH–I (mono-iodo) and F10–OH–2I (di-iodo), with different substitution patterns at the meso-position as candidates for photodynamic therapy (PDT). We employed several optical spectroscopic techniques, including time-resolved spectroscopy from a femtosecond to microsecond and singlet oxygen luminescence to study the properties of excited singlet and triplet states, as well as the singlet oxygen quantum yields. The sub-picosecond internal conversion, ∼1 ps intramolecular vibrational energy redistribution, tens of ps vibrational cooling, are similar across the three corroles. The addition of one (F10–OH–I) and two iodine (F10–OH–2I) atoms to the remote aryl ring of triarylcorroles induces a 4.6-fold and 6.2-fold decrease in fluorescence quantum yields Φ_fl and a 2.2-fold and 4.9-fold increase in the time constant of intersystem crossing k_ISC. In addition, a slight increase in intersystem crossing quantum yields Φ_T was also observed from F10–OH to F10–OH–2I. It means the intersystem crossing is improved by the iodination, from F10–OH to F10–OH–2I, because of the heavy atom effect. However, the sample F10–OH–I, instead of F10–OH–2I, shows the highest singlet oxygen quantum yield Φ_Δ.

The effect of corrole macrocycle meso-iodination on its photophysical character.

Associations of depression with impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes in Chinese adults

AIM

To examine the association between depression and impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes in middle-aged and elderly Chinese people, and whether depression was associated with different treatment regimens or durations of diabetes.

METHODS

A cross-sectional study was performed among 229,047 adults living in the community aged ≥ 40 years from 25 centres in China. The self-reported depression rating scale Patient Health Questionnaire 9 (PHQ-9) was used to diagnose probable and sub-threshold depression. Glucose metabolism status was determined according to World Health Organization 1999 diagnostic criteria.

RESULTS

The numbers of participants with normal glucose regulation, impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes were 120,458, 59,512, 24,826 and 24,251, respectively. The prevalence of sub-threshold depression in the total sample of participants was 4.8% (4.8%, 4.8%, 4.4% and 5.6% from normal glucose regulation to previously diagnosed diabetes, respectively), and the prevalence of probable depression was 1.1% (1.1%, 1.0%, 0.9% and 1.8% from normal glucose regulation to previously diagnosed diabetes, respectively). Compared with participants with normal glucose regulation, those with previously diagnosed diabetes had increased odds of probable depression [odds ratio (OR) = 1.61, 95% confidence interval (CI) 1.39-1.87] and sub-threshold depression (OR = 1.14, 95% CI 1.06-1.24), after adjustment for multiple confounding factors. Newly diagnosed diabetes or impaired glucose regulation was not associated with depression. Among those with previously diagnosed diabetes, insulin treatment was associated with greater odds of depression compared with no treatment or oral anti-diabetic medicine.

CONCLUSION

Previously diagnosed diabetes, but not newly diagnosed diabetes or impaired glucose regulation, was associated with a higher prevalence of depression. Patients receiving insulin were more likely to have depression than those not receiving treatment or being treated with oral anti-diabetic medicine.

Interactions between two magnetohydrodynamic Kelvin-Helmholtz instabilities

Kelvin-Helmholtz instability (KHI) driven by velocity shear is a generator of waves found away from the vicinity of the velocity-shear layers since the fast-mode waves radiated from the surface perturbation can propagate away from the transition layer. Thus the nonlinear evolution associated with KHI is not confined near the velocity-shear layer. To understand the physical processes in multiple velocity-shear layers, the interactions between two KHIs at a pair of tangential discontinuities are studied by two-dimensional magnetohydrodynamic simulations. It is shown that the interactions between two neighboring velocity-shear layers are dominated by the propagation of the fast-mode waves radiated from KHIs in a nonuniform medium. That is, the fast-mode Mach number of the surface waves M(Fy), a key factor of the nonlinear evolution of KHI, will vary with the nonuniform background plasma velocity due to the existence of two neighboring velocity-shear layers. As long as the M(Fy) observed in the plasma rest frame across the neighboring velocity-shear layer is larger than one, newly formed fast-mode Mach-cone-like (MCL) plane waves generated by the fast-mode waves can be found in this region. As results of the interactions of two KHIs, reflection and distortion of the MCL plane waves generate the turbulence and increase the plasma temperature, which provide possible mechanisms of heating and accelerating local plasma between two neighboring velocity-shear layers.

Synthesis of La0.6Nd0.2Na0.2MnO3 nanowire and its magnetism

The colossal magnetoresistance (CMR) manganite La0.6Nd0.2Na0.2MnO3 nanowires were synthesized in porous anodic alumina oxide (AAO) membrane via the sol-gel template route. X-ray diffraction (XRD) results of La0.6Nd0.2Na0.2MnO3/AAO composites verified the purity of the perovskite structure of La0.6Nd0.2Na0.2MnO3. Field emission scanning electron microscopy (FE-SEM) confirmed that the monodisperse cylindrical pores of alumina membrane were filled with manganite nanowire arrays. The nanowires were found to be essentially polycrystalline materials by high-resolution transmission electron microscope (HRTEM) images and selected electron diffraction (SAED) analysis. The Curie temperature of the La0.6Nd0.2Na0.2MnO3 nanowires determined by superconducting quantum interference device (SQUID) was much less than the the Curie temperature of the bulk material. According to our experimental results, we proposed the single domain size should be less than 50 nm conservatively. The result suggested that the finite size effect may play an important role in the reduction of the Curie temperature of the La0.6Nd0.2Na0.2MnO3 nanowires.

Peri-implant and systemic release of metallic elements following insertion of a mandibular modular endoprosthesis in Macaca fascicularis

The aim of this study was to assess the release of metal elements from a Ti6Al4V modular endoprosthesis for mandibular reconstruction. Ten monkeys were included, seven of the animals had an endoprosthesis inserted and three served as controls. Mucosa, regional lymph nodes and distant organs, were assessed after the implant had been in place for 12 months, using light (LM) and transmission electron microscopy (TEM) and inductively coupled plasma optical emission spectroscopy (ICP). Blood was also drawn from all animals for elemental analysis using ICP. LM and TEM evaluation showed no detectable metal particles in the mucosa surrounding the endoprosthesis, nor in the regional lymph nodes and distant organs. Blood analysis revealed that titanium and vanadium were detectable in comparable amounts in the test (Ti: 1.63+/-0.54, Va: 0.42+/-0.08) as well as in the control group (Ti: 2.07+/-0.55, Va: 0.37+/-0.07). The amount of aluminum appeared to be higher in the control group (31.77+/-11.67) compared with the test group (20.41+/-9.13), but this difference was not statistically significant. ICP showed that no titanium, vanadium or aluminum was detectable in the mucosa surrounding the endoprosthesis. In addition, no titanium and vanadium were found in the lymph nodes and distant organs using ICP. On the other hand, using ICP, the aluminum content was found to be higher in the right regional lymph nodes and all examined distant organs as compared to the control group (lymph nodes: 11.55+/-22.15 vs. 0.36+/-0.61, lung: 6.24+/-11.28 vs. 1.40+/-2.15, liver: 1.66+/-0.99 vs. 0, kidney: 15.69+/-24.88 vs 0, spleen: 2.75+/-3.09 vs. 0.49+/-0.43). However, only for the kidney and liver the higher amount of aluminum was statistically significant. In conclusion, this study quantified the release of only aluminum in lymph nodes and distant organs, when using a modular endoprosthesis made of Ti-6Al-4V for mandibular reconstruction.

Ferromagnetism in CaMn(1-x)Ir(x)O(3)

The crystallographic, magnetic, and electric properties of CaMn(1-x)Ir(x)O(3) (0≤x≤0.6) were investigated. The lattice constants increase with increasing content of Ir. Specimens of 0.05≤x≤0.2 show antiferromagnetic behavior; however, ferromagnetism is observed for specimens of 0.3≤x≤0.6. T(N) decreases as the Ir content increases. T(N) is superseded by T(C) without passing 0 K and T(C) continues to increase in the ferromagnetic composition range. The effective moment μ(eff) decreases as the Ir content increases. The Weiss temperature is negative for small x; however, it continues to increase while changing its sign at about x = 0.3. The results were explained by assuming a mixed valence state of Mn(3+), Mn(4+), Ir(4+), and Ir(5+) ions. The composition dependence of μ(eff) could be explained qualitatively using the ion fractions estimated from the Ir content dependence of the unit cell volume. Experimental results suggest the coexistence of antiferromagnetic and ferromagnetic phases. When the volume fraction of the ferromagnetic phase dominates that of the antiferromagnetic phase, the system seems to show ferromagnetism.

Nimesulide-induced hepatotoxicity and fatal hepatic failure

Non-steroidal anti-inflammatory drugs (NSAIDs) and cyclo-oxygenase-2 (cox-2) inhibitors are structurally heterogeneous drugs that share similar therapeutic actions and adverse effects. Hepatotoxicity, although a relatively rare adverse effect of this class of drugs, can be severe. This has led to the withdrawal of some NSAIDs from the market. Nimesulide is an NSAID, with cox-2 preference, which has been reported to cause death from hepatic failure. However, most reports have been from European countries. Asian reports include that from Israel and India. We report three patients who presented with acute hepatitis after being prescribed nimesulide, one of whom died from fulminant hepatic failure.

Investigation of a pyoderma outbreak caused by methicillin-susceptible Staphylococcus aureus in a nursery for newborns

An outbreak of pyoderma caused by methicillin-susceptible Staphylococcus aureus occurred in a nursery for newborns over 26 days. During this period, six neonates were involved. The mother of the first case had trunk pyoderma before delivery, which was regarded as the source of the outbreak. Contamination of the environment and equipment were implicated as the reservoirs of further pathogen spread, as supported by pulsed-field gel electrophoresis (PFGE) results, which showed that some screening isolates were indistinguishable from the epidemic strain. Termination of the outbreak was achieved by the reinforcement of infection control practices and disinfection of environmental surfaces.

Scoring system for empyema thoracis and help in management

OBJECTIVE

To evaluate the implications of a newly defined severity scoring of empyema in children for the prediction of surgical management and to compare the length of hospitalization as an outcome measure of patients treated using medical therapy, salvage video-assisted thoracoscopic surgery (VATS) vs early elective VATS.

METHODS

A retrospective chart review of parapneumonic empyema of patients below 18 years of age admitted to a tertiary children's hospital in northern Taiwan from April 1993 to December 2002 was performed. Patients were categorized into a medical group who received antibiotic therapy, needle aspirations with/without tube thoracostomy; a salvage VATS group when the patients required surgery for the relief of persistent fever > 38 degrees C, chest pains or dyspneic respirations despite initial medical therapy; an early VATS group when the patients received elective surgery early after admission. The demographic data, clinical features, laboratory findings, and duration of hospitalization were compared using a severity score of empyema (SSE).

RESULTS

Streptococcus pneumoniae was the most common infecting organism, followed by Staphylococcus aureus, Pseudomonas aeruginosa. No organisms were recovered in 39% of patients. A pleural pH < 7.1 increases the odds of requiring surgical intervention by 6 times among this cohort. Children who required decortication of empyema had a higher severity score (mean 4.8 vs 3.0, p < 0.005). The duration of hospitalization for patients having early VATS showed a shortening stay (mean 18 vs 28 days) as compared to salvage VATS.

CONCLUSION

A pleural pH < 7.1 and a newly designed clinical severity score of empyema 4 are two predictors of surgical intervention for fibrinopurulent empyema in the present study. Early elective VATS may be adopted not later than 7 days after failure of appropriate antibiotic therapy and adequate drainage of empyema to decrease the length of stay and minimize morbidity.

Hand, foot and mouth disease in Singapore: a comparison of fatal and non-fatal cases

AIM

An epidemic of hand, foot and mouth disease (HFMD) occurred in Singapore between September and November 2000. During the epidemic, there were four HFMD-related deaths and after the epidemic, another three HFMD-related deaths. This study sought to determine the risk factors predictive of death from HFMD disease.

METHODS

The risk factors for fatal HFMD were determined by comparing clinical and laboratory findings between fatal cases (n = 7) and non-fatal controls (n = 131) admitted between September 2000 and April 2001. Enterovirus 71 positive fatal cases (n = 4) and non-fatal controls (n = 63) were also compared.

RESULTS

In total, 138 HFMD cases with a mean age of 32 mo were studied. The majority of fatal cases died from interstitial pneumonitis, of whom three also had brainstem encephalitis. Of the 131 non-fatal cases, 3 had concomitant infections (respiratory syncytial virus bronchiolitis, right-sided pneumonia, Haemophilus influenzae type b meningitis), 2 had aseptic meningitis, and 1 each had transient drowsiness, intravenous immunoglobulin-related complications and transverse myelitis. By multivariate logistic regression analysis, atypical physical findings (p = 0.0006), raised total white cell count (p = 0.0128), vomiting (p = 0.0116) and absence of mouth ulcers (p = 0.043) were predictive of a fatal course. Although previous epidemics have described neurogenic pulmonary oedema as the main cause of death, the fatal cases in this study died mainly from interstitial pneumonitis alone or with myocarditis or encephalitis.

CONCLUSION

Although HFMD is generally a benign disease, risk factors such as vomiting, absence of mouth ulcers, atypical presentation and raised total white cell count should alert the physician of a fatal course of illness.

Ossifying lipoma of the hand: a case report

INTRODUCTION

Ossifying lipoma is an uncommon tumour and its occurrence in the hand is rare. It is often not diagnosed preoperatively.

CLINICAL PICTURE

Our case presented with a lump in the hand which was painful with activity. The lipomatous component of the tumour was radiologically not distinguishable.

TREATMENT

The hand was explored through a wide palmar incision, revealing a lipomatous tumour. The tumour was completely excised and diagnosis made after histological examination.

OUTCOME

After 1 year, the patient has had normal function of the hand with no tumour recurrence.

DISCUSSION

The diagnosis of ossifying lipoma could be made with certainty only after radiological examination, excision and histological examination. The bony component is of mesenchymal origin and may come about as a result of metaplastic transformation.

Idiopathic pulmonary hemosiderosis in a child: report of one case

Idiopathic pulmonary hemosiderosis (IPH) is uncommon in children. We report a 3-year-old girl who was presented with acute pale-looking appearance, hemoptysis, hematemesis and shortness of breath. This patient was confirmed to have pulmonary hemorrhage by the presence of hemosiderin-laden macrophages in the bronchoalveolar lavage fluid using a flexible bronchoscope. Other causes of PH including glomerular, cardiac and immunological disorder were excluded by normal laboratory studies. She was primarily treated by oral prednisolone, but due to recurrent hemoptysis, immunosuppressive agent was added for maintenance therapy. Pediatricians should consider PH in a patient who has recurrent dyspnea, hemoptysis and iron deficiency anemia.

Effect of hypocapnia in the first three days of life on the subsequent development of periventricular leukomalacia in premature infants

Several etiologies for causing periventricular leukomalacia (PVL) in preterm infants have been investigated worldwidely. The aim of this study is to investigate whether hypocapnia plays a role in the pathogenesis of the subsequent development of PVL. From Jan. 1997 to June 1998, 91 premature infants (mean gestational age 28.8 +/- 2.5 weeks and birth body weight 1169 +/- 385 g) born in Chung Gung Children's Hospital requiring mechanical ventilation in the first 72 hrs were enrolled in our study. Serial neuorosonogram were followed on day 1, 3, 7 and then at least every 2 to 3 weeks until discharge. These infants were divided into two groups defined as the PVL group and non-PVL group. Variables comprising perinatal data were analyzed and compared between these two groups to screen out possible risk factors related to the development of PVL. There was no difference noted. As for the effect of PaCO2, we found the infants with PVL to have mean lower PaCO2 during the first 72 hours of life. (P = 0.004). Logistic regression model revealed that the incidence for PVL increased significantly when mean PaCO2 is lowered to less than 25 mmHg. Hypocapnia during the first three days of life seems to be an important etiological factor associated with the development of periventricular leukomalacia. Therefore, the ventilatory strategy in the care of the premature neonates should not only provide adequate ventilation but also careful avoidance of hypocapnia.

Fatal retroperitoneal haemorrhage: an unusual complication of percutaneous endoscopic gastrostomy

A 93-year-old lady with dementia, neurological dysphagia and aspiration pneumonia, died from massive retroperitoneal haemorrhage which developed as a rare and, it is believed, hitherto unreported, complication of percutaneous endoscopic gastrostomy (PEG), which was performed for feeding purposes. It is postulated that the initial, unsuccessful attempt at needle puncture of the stomach, under endoscopic guidance, had resulted in iatrogenic perforation and laceration of the splenic and superior mesenteric veins close to their confluence with the portal vein. It would also appear that dense fibrous adhesions between the pyloro-antral region of the stomach and the posterior hepatic surface had altered the immediate anatomical relations of the stomach in such a manner as to have predisposed to these events.

Effect of carbon dioxide tension in the first three days of life on the development of retinopathy of prematurity

BACKGROUND

This study focuses on the effect of carbon dioxide tension in the first 3 days of life on the development of retinopathy of prematurity (ROP) in mechanically ventilated premature infants.

METHODS

From January 1997 to June 1998, 91 premature infants (gestational age 28.8 +/- 2.5 weeks, birth weight 1169 +/- 385 g) born in Chung Gung Children's Hospital requiring mechanical ventilation in the first 72 hours were enrolled in our study. Ophthalmic examination was performed initially at 4-6 weeks of age and then every week if ROP was found and every other week if the result was normal until discharge. These infants were divided into 2 groups: those with and without ROP. Medical records of the highest and lowest blood gas measurements were recorded during the first 3 days of life. To screen for possible risk factors related to the development of ROP within these 2 groups, variables comprising perinatal data were compared.

RESULTS

The perinatal factors were compared, whish showed that infants with ROP had a lower mean gestational age (p < 0.001), mean birth body weight (p < 0.001), and a longer duration under mechanical ventilation (p < 0.001). The severity and incidence of ROP were not affected by either hypercapnia or hypocapnia; even with the superimposed effect of hyperoxia, the effect was minimal.

CONCLUSION

Hypercarbia or hypocarbia in the first 3 days of mechanically ventilated preterm neonates does not affect the subsequent development of retinopathy of prematurity. However, a lower gestational age and birth weight as well as longer-duration mechanical ventilation might be independent predictors for the occurrence of ROP. The role of PaCO2 in the pathophysiology of retinopathy of prematurity remains undetermined, and further investigation in the future is warranted.

Non-infectious epiglottitis in children: two cases report

Two young children who suffered from thermal injuries to the epiglottis after swallowing corrosive agent and hot water respectively. Findings, clinically and radiologically, in both children were similar to acute infectious epiglottitis. Both recovered quickly with close observation and parenteral antibiotics. Although Haemophilus influenzae type b (Hib) is the major pathogen of epiglottitis, in areas with low incidence of Hib infection and high vaccination rates, non-infectious epiglottic swelling should be considered first.

A hierarchical neural network algorithm for robust and automatic windowing of MR images

A novel hierarchical neural network based algorithm for automatic adjustment of display window width and center for a wide range of magnetic resonance (MR) images is presented in this paper. The algorithm consists of a feature generator utilizing both wavelet histogram and compact spatial statistical information computed from a MR image, a competitive layer based neural network for clustering MR images into different subclasses, two pairs of a radial basis function (RBF) network and a bi-modal linear estimator for each subclass, as well as a data fusion process using estimates from both estimators to compute the final display parameters. Both estimators can adapt to new kinds of MR images simply by training them with those images, which make the algorithm adaptive and extendable. The RBF based estimator performs very well for images that are similar to those in the training data set. The bi-modal linear estimator provides reasonable estimations for a wide range of images that may not be included in the training data set. The data fusion step makes the final estimation of the display parameters accurate for trained images and robust for the unknown images. The algorithm has been tested on a wide range of MR images and has shown satisfactory results.

A new variational shape-from-orientation approach to correcting intensity inhomogeneities in magnetic resonance images

A new intensity inhomogeneity correction algorithm based on a variational shape-from-orientation formulation is presented. Unlike most previous methods, the proposed algorithm is fully automatic, widely applicable and very efficient. Since no prior classification knowledge about the image is assumed in the proposed algorithm, it can be applied to correct intensity inhomogeneities for a wide variety of medical images. In this paper, a finite-element method is used to model the smooth bias-field function. Orientation constraints for the bias-field function are computed at the nodal locations of the regular discretization grid away from the boundary between different class regions. The selection of reliable orientation constraints is facilitated by the goodness of fit of a first-order polynomial model to the neighborhood of each nodal location. The automatically selected orientation constraints are integrated in a regularization framework, which leads to minimization of a convex and quadratic energy function. This energy minimization is accomplished by solving a linear system with a large, sparse, symmetric and positive semi-definite stiffness matrix. We employ an adaptive preconditioned conjugate-gradient algorithm to solve the linear system very efficiently. Experimental results on a variety of magnetic resonance images are given to demonstrate the effectiveness and efficiency of the proposed algorithm.

A novel local PCA-based method for detecting activation signals in fMRI

A novel local principal component analysis (LPCA) technique is presented for activation signal detection in functional magnetic resonance imaging (fMRI) without explicit knowledge about the shape of the model activation signal. Unlike the traditional PCA methods, our LPCA algorithm is based on a measure of separation between two clusters formed by the signal segments in active periods and inactive periods, which is computed in an eigen-subspace. In addition, we only applied PCA to the temporal sequence of each individual voxel instead of applying PCA to the fMRI data set. In our algorithm, we first applied a linear regression procedure to alleviate the baseline drift artifact. Then, the baseline-corrected temporal signals were partitioned into active and inactive segments according to the paradigm used for the fMRI data acquisition. Principal components were computed from all these segments for each voxel by PCA. By projecting the segments of each voxel onto a linear subspace formed by the corresponding most dominant principal components, two separate clusters were formed from active and inactive segments. An activation measure was defined based on the degree of separation between these two clusters in the projection space. We show experimental results on the activation signal detection from various sets of fMRI data with different types of stimulation by using the proposed LPCA algorithm and the standard t-test method for comparison. Our experiments indicate that the LPCA algorithm in general provides substantial signal-to-noise ratio improvement over the t-test method.

Fast numerical algorithms for fitting multiresolution hybrid shape models to brain MRI

In this paper, we present new and fast numerical algorithms for shape recovery from brain MRI using multiresolution hybrid shape models. In this modeling framework, shapes are represented by a core rigid shape characterized by a superquadric function and a superimposed displacement function which is characterized by a membrane spline discretized using the finite-element method. Fitting the model to brain MRI data is cast as an energy minimization problem which is solved numerically. We present three new computational methods for model fitting to data. These methods involve novel mathematical derivations that lead to efficient numerical solutions of the model fitting problem. The first method involves using the nonlinear conjugate gradient technique with a diagonal Hessian preconditioner. The second method involves the nonlinear conjugate gradient in the outer loop for solving global parameters of the model and a preconditioned conjugate gradient scheme for solving the local parameters of the model. The third method involves the nonlinear conjugate gradient in the outer loop for solving the global parameters and a combination of the Schur complement formula and the alternating direction-implicit method for solving the local parameters of the model. We demonstrate the efficiency of our model fitting methods via experiments on several MR brain scans.

Human breast sarcoma and human breast implantation: a time trend analysis based on SEER data (1973-1990)

Since the demonstration in the 1940s of foreign body induction of sarcomas in rodents, the safety of artificial implants in humans has been a matter of concern. In this study, we assess the risk for the development of breast sarcomas in women with silicone breast implants. Our analysis is based on the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program database for the years 1973-1990 and on estimates of breast implantation rates from about 1960 onward. We have divided the SEER data into two equal time periods, 1972-1981 and 1982-1990. For each time period, we estimated the average annual number of women in the United States who had received breast implants 10 or more years earlier. This analysis allows for a 10 year latency period for the induction of breast sarcoma. We calculated that the average number of women in the U.S. 10 or more years post breast implantation was 55,000 for the 1973-1981 period and 509,000 for the 1982-1990 period. We then examined the SEER data to observe whether there was a concomitant rise in the female breast sarcoma incidence rates between these two time periods. We found the mean age-adjusted incidence rate of breast sarcomas was 0.13 per 100,000 women for the initial 9-year period, 1973-1981, and 0.12 per 100,000 women for the latter 9-year period, 1981-1990.(ABSTRACT TRUNCATED AT 250 WORDS)

Quantitative analysis of human immunodeficiency virus type 1 antibody reactivity by western immunoblots: evaluation of relative antibody levels in seropositive individuals and mothers

A quantitative analysis of antibody responses to human immunodeficiency virus type 1 (HIV-1) proteins using Western immunoblots and 125I-labeled protein A is reproducible and can be validated. The antibody levels obtained by Western immunoblots were compared with stoichiometric p24 radioimmunoassay over a wide range of antibody (correlation coefficient, .94; P less than .001). Antibody levels to gp160 and gp120 were validated using purified antigens. Analysis of antibody levels from 31 seropositive individuals revealed a statistically significant correlation between antibody levels to p24 and the other viral proteins except gp120. Anti-gag p24 antibody was strongly correlated with antibodies to other env products, specifically gp41 and gp160. Using the validated assay, HIV-1-infected mothers of infants were found to have highly variable levels of antibody to all viral proteins. Mothers of infected infants did not differ significantly from mothers of uninfected infants in antibody pattern or levels to any viral protein including gp120.

Combination therapy with zidovudine and dideoxycytidine in patients with advanced human immunodeficiency virus infection. A phase I/II study

OBJECTIVE

To evaluate the safety and immunologic and antiviral effects of combination therapy with zidovudine and dideoxycytidine (ddC) in patients with advanced human immunodeficiency virus type 1 (HIV) infection.

DESIGN

A phase I/II open-label, dose-ranging study.

SETTING

Two AIDS Clinical Trials Group units.

PATIENTS

Patients (56) with advanced HIV disease.

INTERVENTIONS

Patients were randomly assigned to one of three paired regimens of zidovudine and ddC. We evaluated six dosing regimens, each involving oral administration of the study drugs at 8-hour intervals.

MEASUREMENTS

Pharmacokinetics, toxicity, CD4 counts, p24 antigenemia and clinical end points.

MAIN RESULTS

The median follow-up period was 40.6 weeks (range, 0.3 to 70 weeks). Neither drug affected the pharmacokinetic profile of the other. Episodes of serious hematologic toxicity were infrequent, occurring in only 17.9% of patients, and did not differ among the regimens (P = 0.15). Severe sensory peripheral neuropathy occurred in two patients (one patient each in regimens 1 and 4). One patient receiving regimen 4 died. The mean maximal increase in CD4 counts exceeded 109 cells/mm3, and 69% of patients receiving combinations containing 300 or 600 mg of zidovudine daily had an increase in CD4 counts of 50 cells/mm3 or greater. Regimens containing 600 mg of zidovudine daily (regimens 2 and 5) were also more likely to result in persistent increases in CD4 counts above pretreatment values than were the two lowest dose regimens (P = 0.003). The decline in CD4 counts was more rapid, and the suppression of the p24 antigenemia was less rapid and less sustained in patients receiving the lowest zidovudine dose alone (regimen 6). The addition of ddC to regimen 6 (regimen 3) resulted in a slower decline in the CD4 counts (P = 0.06).

CONCLUSIONS

Combination therapy with zidovudine and ddC at the doses tested was well tolerated and did not result in toxicity. A daily oral dose of 150 mg of zidovudine appeared to produce a suboptimal effect on p24 antigenemia and CD4 counts. Combination therapy with ddC and higher doses of zidovudine produced greater and more persistent effects in patients with advanced HIV infection compared with other study regimens and with the results of previous trials of zidovudine monotherapy.

The donation and sale of blood by intravenous drug users

In spite of efforts to dissuade intravenous drug users (IVDUs) from donating or selling blood, some continue to do so. As part of a longitudinal study, 915 IVDUs in South Florida were interviewed concerning their history of donation or sale of blood and tested for antibodies to HIV-1 and HTLV-I/II. Approximately 17 percent had either donated or sold blood during 1985 through 1988; most contributors (80.4 percent) sold to commercial blood services. IVDUs who had donated/sold blood were more likely to be male and not in drug treatment than were those who had not contributed blood. IVDUs not in treatment at the time of interview were more likely than IVDUs in treatment to have sold blood. Of those who had donated/sold blood since 1985, 19.6 percent subsequently tested positive for antibodies to HIV-1 and 5.7 percent were positive for antibodies to HTLV-I/II. Increased effort is required to screen prospective donors and sellers, particularly at commercial blood banks.

A hospital-based prospective study of perinatal infection with human immunodeficiency virus type 1

Most infants with pediatric acquired immunodeficiency syndrome and infections with human immunodeficiency virus type 1 (HIV-1) are infected perinatally by their mothers. To determine the proportion of exposed infants who are infected, we conducted a hospital-based prospective study in HIV-1-infected women whose infants were delivered at a single metropolitan hospital in Miami, Fla. A population of uninfected women and their infants was also enrolled and followed longitudinally for 2 years to assess laboratory and clinical measurements. The median follow-up is now 18 months for 82 infants born to HIV-1-infected mothers. The proportion of infected infants in this group is 0.30 (25/82). None of the infants born to 110 HIV-1-seronegative mothers were seropositive. Infected infants were easily distinguished from noninfected infants by virus isolation. No single immunologic or hematologic measure was predictive of infection for all infants at risk for HIV-1 infection who were 6 months of age or younger. As a group, however, infected infants could be distinguished from uninfected index infants by a number of immunologic measures by 6 months of age; the absolute number of CD4+ lymphocytes and the CD4+/CD8+ lymphocyte ratio were the variables most predictive of infection. As in retrospective studies, clinical disease developed in 80% of infected infants within the first 24 months of life. This study provides documentation of HIV-1 perinatal transmission risk and early correlates of infection in young infants from a single hospital.

HTLV-I/II seropositivity and death from AIDS among HIV-1 seropositive intravenous drug users

In a prospective study of street-recruited intravenous drug users (IVDUs) in Miami, Florida, USA, 107 (46.5%) of 230 IVDUs were infected with HIV-1. Of these HIV-1 seropositive individuals, 23 were also infected with human T-lymphotropic virus type I or II (HTLV-I/II). To test the hypothesis that HTLV-I/II infection has an effect on the survival of HIV-1 seropositive IVDUs, various baseline clinical and laboratory HIV-1 related indices in HTLV-I/II positive and negative groups were compared. Life table analysis and Cox's proportional hazards model were used to estimate the potential effect of HTLV-I/II infection on the survival patterns of people infected with HIV-1. IVDUs infected with both viruses were three times more likely to die from AIDS during follow-up than were those infected with HIV-1 only. This finding suggests that HTLV-I/II seropositivity may adversely affect the clinical outcome of HIV-1 seropositive patients.

Urinary electrolytes and blood pressure in three Yi farmer populations, China

The relation between blood pressure and urinary electrolytes, including sodium, potassium, calcium, and magnesium were examined in male farmers of the Yi nationality who live in three separate communities in Sichuan and Yunnan provinces in China, where the lifestyles, habits, and living conditions are very different. One of these three communities was unacculturated and had the lowest average blood pressure as well as the lowest prevalence rate of hypertension in China; one was acculturated and had the highest average blood pressure; and the third was moderately acculturated with its average blood pressure between the other two. Blood pressure was taken on each of 3 days and corresponding 24-hour urine specimens were collected to measure potassium, sodium, calcium, magnesium, urea nitrogen, and creatinine. Ecological and individual-based data correlation analyses were employed to study the relations among age, body mass index, some related indexes of electrolyte derivatives, and blood pressure. Multiple regression analyses were used to explore the relation of blood pressure to the above indexes, adjusted for age, body mass index, urea nitrogen and creatinine, and geographical differences. Statistically significant correlation analyses showed that systolic blood pressure was positively associated with sodium-creatinine, calcium-creatinine, sodium-potassium, calcium-magnesium, and urea nitrogen and creatinine ratios; negatively associated with potassium-creatinine and magnesium-creatinine ratios. The ridge regression analysis selected only calcium-magnesium ratio as a predictor of systolic blood pressure.

Oral contraceptives and premenopausal breast cancer in nulliparous women

Characteristics of women with potential for modifying the relationship between use of oral contraceptives (OCs) and the risk of premenopausal breast cancer were investigated using data from the Cancer and Steroid Hormone study, a population-based, case-control study conducted in eight geographic areas of the United States. Cases consisted of 2945 women who were premenopausal and 20-54 years of age when breast cancer was diagnosed between December 1, 1980, and December 31, 1982; controls consisted of 2646 women with no history of breast cancer who were also premenopausal and 20-54 years of age when selected during the same period. Results are presented with the cases and controls divided into eight groups on the basis of age at diagnosis on selection (20-44, 45-54), parity (0, greater than or equal to 1), and age at menarche (less than 13, greater than or equal to 13). Among nulliparous women who experienced menarche before age 13, the relative risk of developing breast cancer in the age interval 20-44 years is estimated to be 1.0 for never-users of OCs (reference), 1.3 for greater than 0-3 years of use (95% confidence intervals 0.7-2.4), 1.3 for 4-7 years (95% CI 0.7-2.6), 2.7 for 8-11 years (95% CI 1.2-6.3), and 11.8 for 12 years or longer (95% CI 1.4-95.7). OC use is not significantly related to the risk of breast cancer among women in any of the other seven groups. These findings suggest that prolonged OC use may accelerate the onset of breast cancer for a small group of susceptible women while having no appreciable impact on overall risk. The findings should be regarded as tentative, however, since they are based upon numerous comparisons and because age of menarche was stratified at 13 years to highlight the concentration of breast cancer risk apparent in our data.

Breast cancer risk in relation to type of estrogen contained in oral contraceptives

We report analyses designed to address the recent hypothesis that women who use combination-type OCs containing ethinylestradiol (EE) are at increased risk of breast cancer before age 45, if use of such OCs occurs prior to first term pregnancy (FTP). Our findings, based on data from 1679 cases and 1689 controls, 20-44 years of age, from the population-based Cancer and Steroid Hormone Study, are against the hypothesis. The relative risk of breast cancer by duration of exclusive use prior to FTP of OCs containing EE is estimated to be 1.0 (1-12 months EE use), 1.2 (13-48 months EE use), and 0.9 (49+ months EE use). There was no evidence of a latent effect. Among parous women with 49+ months exclusive use prior to FTP of EE-containing OCs, the relative risk of breast cancer was estimated as 0.9 (0-4 years after FTP) and 0.6 (5-9 years after FTP). Among nulliparous women with 49+ months exclusive use of EE-containing OCs, the relative risk of breast cancer was estimated as 1.0 (0-4 years since first use), 0.7 (5-9 years since first use), and 1.1 (10-14 years since first use). With regard to exclusive use of OCs containing mestranol, parous women who used such preparations long-term before their FTP showed no alteration of breast cancer risk, even 15 years or more after pregnancy. Nulliparous women with exclusive use of ME-containing OCs did show elevations in breast cancer risk, but the magnitude of risk in relation to duration of use and latent interval shows no pattern that suggests a cause-effect relationship.

Cantonese-style salted fish as a cause of nasopharyngeal carcinoma: report of a case-control study in Hong Kong

Two hundred fifty incident cases of nasopharyngeal carcinoma under age 35 years in Hong Kong Chinese and an equal number of age- and sex-matched friend controls were interviewed. Mothers of cases and controls were interviewed also, if available, to obtain information on childhood events concerning the study subjects. Consumption of Cantonese-style salted fish during all time periods was significantly associated with nasopharyngeal carcinoma; the association was especially strong during childhood. The relative risk for having Cantonese-style salted fish as one of the first solid foods during weaning was 7.5 (95% confidence limits, 3.9, 14.8), and the relative risk for consuming the food at least once a week compared to less than once a month at age 10 years was 37.7 (95% confidence limits, 14.1, 100.4). It is estimated that over 90% of young nasopharyngeal carcinoma cases in Hong Kong Chinese can be attributed to consumption of this food during childhood.

Relationship between salt excretion and blood pressure in various regions of China: Part 2

Overnight urine samples were collected on three consecutive days from 2483 persons in 12 regions of China and the mean 9-hour overnight sodium and potassium levels subsequently determined. Analysis of the data by univariate regression, simple correlation, and multiple regression indicated that there was a positive correlation between the mean level of sodium in urine and blood pressure.

Relationship between salt excretion and blood pressure in various regions of China

Overnight urine samples were collected on three consecutive days from 3105 persons in 12 regions of China, and analysed for levels of sodium and potassium. The mean 9-hour overnight urine sodium level ranged from 49.51 to 139.12 mmol, and urine potassium from 6.32 to 18.43 mmol. Univariate regression, simple correlation analysis, and multivariate ridge regression analysis were carried out on the data. A positive correlation between blood pressure and urine sodium or sodium/potassium ratio was found in each of the twelve regions. Urine potassium showed a negative correlation with blood pressure in three regions.

Establishment of a cell line (NPC/HK1) from a differentiated squamous carcinoma of the nasopharynx

A long-term cell culture epithelioid cell line was established from a recurrent squamous carcinoma of the nasopharynx of a Chinese male 17 1/2 years after radiation therapy. The cell line, designated NPC/HK1, has been passed 72 times over a period 1 year. The cells have been shown by light and electron microscopies to be of the squamous epithelial type. When they were transplanted subcutaneously into the back of athymic nude BALB/c (nu/nu) mice, tumors developed at the sites of inoculation, which on histological examination were shown to be well-differentiated squamous carcinomas, similar in morphology to the recurrent human tumor from which they were derived. Karyotypic analysis of cells from the cell line demonstrates an aneuploid human type with a modal chromosome number of 74 with both numerical and structural aberrations. Viral particles or Epstein-Barr viral nuclear antigen (EBNA) has not been demonstrated in the cells from the primary culture or several of the subcultures tested. The presence of EBNA in touch smears prepared from the biopsy tissue was inconclusive. Infection of the subcultured cells with EBV from P3HR1 and B95-8 cells was unsuccessful.