Biomedical subjects

B Miller

Publications and source records attributed to B Miller.

At least 37 records · Page 2Linked to original sources

PubMed2001

Putative non-uniting double central retinal artery system.

PURPOSE: To report a case of probable non-uniting double retinal arterial circulation. METHODS: Case report. A 66-year-old man suffered central retinal artery occlusion. RESULTS: The medical findings and angiographic workup supported the existence of double central retinal circulation not uniting before entering the globe and independently branching in the retina. CONCLUSIONS: In previously recognized unusual anatomic structures of the central retinal artery two parallel arteries were recognized, both of which united before entering the globe. We have described a rare anatomic variant in which those arteries remained separated after entering the globe, including while branching in the retina.

Aged↗

PubMed2001

Magnetodendrimers allow endosomal magnetic labeling and in vivo tracking of stem cells.

Magnetic resonance (MR) tracking of magnetically labeled stem and progenitor cells is an emerging technology, leading to an urgent need for magnetic probes that can make cells highly magnetic during their normal expansion in culture. We have developed magnetodendrimers as a versatile class of magnetic tags that can efficiently label mammalian cells, including human neural stem cells (NSCs) and mesenchymal stem cells (MSCs), through a nonspecific membrane adsorption process with subsequent intracellular (non-nuclear) localization in endosomes. The superparamagnetic iron oxide nanocomposites have been optimized to exhibit superior magnetic properties and to induce sufficient MR cell contrast at incubated doses as low as 1 microg iron/ml culture medium. When containing between 9 and 14 pg iron/cell, labeled cells exhibit an ex vivo nuclear magnetic resonance (NMR) relaxation rate (1/T2) as high as 24-39 s-1/mM iron. Labeled cells are unaffected in their viability and proliferating capacity, and labeled human NSCs differentiate normally into neurons. Furthermore, we show here that NSC-derived (and LacZ-transfected), magnetically labeled oligodendroglial progenitors can be readily detected in vivo at least as long as six weeks after transplantation, with an excellent correlation between the obtained MR contrast and staining for beta-galactosidase expression. The availability of magnetodendrimers opens up the possibility of MR tracking of a wide variety of (stem) cell transplants.

3T3 Cells↗

PubMed2001

Effects of supratherapeutic doses of ebastine and terfenadine on the QT interval.

AIMS: The objective of this study was to compare the effects of high doses of ebastine with terfenadine and placebo on QTc. METHODS: Thirty-two subjects were randomly assigned to four treatments (ebastine 60 mg x day(-1), ebastine 100 mg x day(-1), terfenadine 360 mg x day(-1), placebo) administered for 7 days. Serial ECGs were performed at baseline and day 7 of each period. QT interval was analysed using both Bazett (QTcB) and Fridericia (QTcF) corrections. RESULTS: Ebastine 60 mg (+ 3.7 ms) did not cause a statistically significant change in QTcB compared with placebo (+ 1.4 ms). The mean QTcB for ebastine 100 mg was increased by + 10.3 ms which was significantly greater than placebo but was significantly less (P < 0.05) than with terfenadine 360 mg (+ 18.0 ms). There were no statistically significant differences in QTcF between ebastine 60 mg (-3.2 ms) or ebastine 100 mg (1.5 ms) and placebo (-2.1 ms); although terfenadine caused a 14.1 ms increase which was significantly different from the other three treatments. The increase in QTcB with ebastine most likely resulted from overcorrection of the small drug-induced increase in heart rate. CONCLUSIONS: Ebastine at doses up to five times the recommended therapeutic dose did not cause clinically relevant changes in QTc interval.

Adolescent↗

PubMed2001

Sleep-disordered breathing in stable methadone programme patients: a pilot study.

AIMS: To explore the possibility that stable MMP patients have sleep-disordered breathing (SDB) and abnormal sleep architecture defined by nocturnal sleep stages and sleep efficiency. DESIGN: Observational. SETTING: Regional Methadone Service and sleep disorders laboratory in a university affiliated hospital. Participants and measurements. Ten stable MMP patients and nine normal subjects were assessed clinically and with overnight polysomnography. FINDINGS: There were no differences in age, sex and body mass index between the groups. The methadone dose ranged between 50 and 120 mg/day. Six patients had central apnoea index (CAI) greater than 5, four had a CAI greater than 10 and three of these exhibited periodic breathing. No normal subject had central sleep apnoea. The patients had lower sleep efficiency (p < 0.05), less slow wave sleep (p < 0.01), less rapid eye movement sleep (p < 0.05) and more Stage 2 sleep (p < 0.05) than controls. CONCLUSIONS: Stable MMP patients have more sleep architecture abnormalities than controls and a higher prevalence of central sleep apnoea. Further studies are needed to confirm these findings, to delineate the mechanisms for the abnormalities and to assess whether the SDB is related to sudden death in stable MMP patients. We recommend that MMP patients have awake and sleep respiration assessed to identify those potentially at risk.

Adult↗

PubMed2001

Once-daily desloratadine improves the signs and symptoms of chronic idiopathic urticaria: a randomized, double-blind, placebo-controlled study.

BACKGROUND: Chronic idiopathic urticaria (CIU) is the most common type of chronic urticaria, and pruritus is the most prominent symptom. Antihistamines are the first-line treatment for CIU. Sedation and anticholinergic adverse effects are often experienced with the first-generation antihistamines and there is a risk of cardiovascular adverse effects and drug interactions with some second-generation agents. Hence, new treatment options are needed. Desloratadine is a new, potent, nonsedating antihistamine that has an excellent cardiovascular safety profile. METHODS: This was a multicenter, randomized, double-blind, placebo-controlled study designed to determine the efficacy and safety of desloratadine in the treatment of moderate-to-severe CIU. A total of 190 patients, aged 12-79 years, with at least a 6-week history of CIU and who were currently experiencing a flare of at least moderate severity, were randomly assigned to therapy with desloratadine 5 mg or placebo once daily for 6 weeks. Twice daily, patients rated the severity of CIU symptoms (pruritus, number of hives, and size of largest hive), as well as the impact of CIU symptoms on sleep and daily activity. Patients and investigators jointly evaluated therapeutic response and overall condition. Safety evaluations included the incidence of treatment-emergent adverse events, discontinuations due to adverse events, and changes from baseline in vital signs, laboratory parameters, and ECG intervals. RESULTS: Desloratadine was superior to placebo in controlling pruritus and total symptoms after the first dose and maintained this superiority to the end of the study. Measures of sleep, daily activity, therapeutic response, and global CIU status were also significantly better with desloratadine after the first dose; these clinical benefits were also maintained throughout the 6-week study. No significant adverse events occured. CONCLUSIONS: Desloratadine 5 mg daily is a safe and effective treatment for CIU with significant benefits within 24 h and maintained through the treatment period.

Adolescent↗

PubMed2001

Young patients with colorectal cancer: how do they fare?

BACKGROUND: Younger patients with colorectal cancer (CRC) have long been thought to have a poorer prognosis than older patients. Recent overseas reports, however, have disputed this. The aim of the present study was to conduct a review of data on patients with colorectal cancer collected over a 29-year period at Princess Alexandra Hospital (PAH) to ascertain the outcome of a younger subset of patients at this hospital. METHODS: The PAH Colorectal Project records on 2495 patients with malignancies of the colon, rectum and anus who were treated and followed since 1971, were analysed to determine clinical presentation, treatment and outcome. A group of 61 patients with colo-rectal adenocarcinoma was identified who were aged less than 40 years at presentation. Their clinical data were then compared with the larger group of older patients. RESULTS: There were 30 male and 31 female patients in the younger group. A positive family history was the most consistent risk factor, present in 34% of patients. Despite this, only one patient out of 61 had been diagnosed as a result of a screening programme. The Australian Clinico-Pathological Stage (ACPS), histology and distribution of tumours corresponded to that of the older patients. The overall 5-year survival among younger patients was 53%. The 5-year survival rates in younger patients were better than that for older patients for ACPS A and B, reaching statistical significance for both of these stages. CONCLUSIONS: Our results indicate that younger patients with colorectal cancer have the potential to do just as well as older ones. With the influence of a family history of colorectal cancer being very apparent in this group, greater emphasis should be placed on an adequate screening programme for them.

Adenocarcinoma↗

PubMed2001

Renal transplantation following previous heart, liver, and lung transplantation: an 8-year single-center experience.

BACKGROUND: Long-term follow-up of heart, liver, and lung transplantation has led to an increased recognition of secondary end-stage renal failure (ESRF) in transplant recipients. This study examines our center's experience with renal transplantation following previous solid organ transplantation. METHODS: From January 1, 1992, to September 30, 1999, our center performed 18 renal transplants in previous solid organ recipients. During the same period, 815 total renal transplants were performed. One- and 3-year graft and patient survival, recipient demographics, donor type, and reason for transplantation were compared between these groups. RESULTS: Of the 18 recipients, 7 had prior heart transplants, 4 had prior liver transplants, and 7 had prior lung transplants. Cyclosporine toxicity contributed to renal failure in 17 (94.4%) of the patients-either as a sole factor (11 patients) or in combination with hypertension, renal artery stenosis, or tacrolimus toxicity (6 patients). Kaplan-Meier 1- and 3-year patient survival was 82.9% and 73.7%, compared with 95.5% and 90.7% in all renal transplant recipients. No surviving patient has suffered renal allograft loss. Mean current creatinine level is 1.4 mg/dL. CONCLUSIONS: Renal transplantation is an excellent therapy for ESRF following prior solid organ transplantation. One and 3-year patient and graft survival demonstrate the utility of renal transplantation in this patient population.

Follow-Up Studies↗

PubMed2001

Functional status examination: a new instrument for assessing outcome in traumatic brain injury.

The Functional Status Examination (FSE) is a new measure designed to evaluate change in activities of everyday life as a function of an event or illness, including traumatic brain injury. The measure covers physical, social, and psychological domains. The FSE is based on a structured interview and includes levels of functioning that accommodate the full spectrum of possible outcomes, from death through recovery to preinjury functioning. Based on 133 prospectively studied patients with moderate to severe traumatic brain injury, the FSE has favorable psychometric properties including good test-retest reliability (r = 0.80) and close correspondence of assessments provided by the patient and their significant other (SO; r = 0.80). The FSE correlated significantly with each of three severity indices with closest relationships occurring between the FSE assessed by the SO and posttraumatic amnesia (r = 0.76). The FSE assessed by the SO was significantly (p < 0.05) more closely related to each severity index than the Glasgow Outcome Scale (GOS) or Sickness Impact Profile and, for two of the three indices, than the SF-36. All measures showed significant change from 1 to 6 months after injury with the FSE showing the largest effect sizes. The FSE is significantly related to important constructs such as family burden, SO depression, and sacrifices the family makes, as well as overall indices of recovery and satisfaction with level of functioning. The latter relationships are significantly stronger than for the GOS. The FSE has demonstrated good reliability, validity, and sensitivity, and appears to be a promising instrument for monitoring recovery and assessing functional status in clinical trials.

Activities of Daily Living↗

PubMed2001

Social support and caregiver distress: a replication analysis.

OBJECTIVES: Prior studies have conceptualized and operationalized social support in different ways, making it difficult to determine if the inconsistencies in findings are due to differences in study design, samples, conceptualization, or measurement. The present study examined the replicability of models of social support and caregiver distress across 4 community-based caregiving studies representative of many conducted in the past 10 years. The goal was to identify areas of consistency in findings across the data sets. METHODS: The authors analyzed 3 models specifying patterns of relationship between social support and depression (main effect, mediation effect, and moderation effect) separately within data sets using hierarchical ordinary least squares regression. Results were compared across data sets. RESULTS: The replication analysis confirmed the robustness of behavior problems and caregiver health as important contributors to caregiver distress. Results of hypotheses examining the pattern of relationship between social support and distress were inconsistent, however. Only 1 type of social support was associated with distress in the expected direction: Less emotional support was associated with higher levels of distress in 2 of the 4 data sets. DISCUSSION: More complex theoretical models that incorporate common measures to represent the linkages between types of stressor, types of support, and their interactions are needed to foster replicability and generalizability of research results.

Adult↗

PubMed2001

Depressive symptomatology in middle-aged and older married couples: a dyadic analysis.

OBJECTIVES: Depressive symptomatology has been frequently conceptualized as an individual matter, but social contextual models argue that symptom levels are likely to covary in close relationships. The present study investigated correlation between spouses' depressive symptomatology in middle-aged and older married couples, the influence of gender and race/ethnicity in predicting variability in symptom level, and the importance of individual-level covariates (education, health, and age) and couple-level covariates (household income and net worth). METHODS: Results were based on secondary analysis of Wave 1 interviews with White, Black, and Mexican American married couples (N = 5,423) from the Health and Retirement Study (HRS) and the Study of Asset and Health Dynamics Among the Oldest Old (AHEAD). Dyadic data from husbands and wives were analyzed with multilevel modeling. RESULTS: Husbands' and wives' depressive symptoms were moderately correlated, gender and race/ethnicity (and their interaction) predicted depressive symptoms, and both individual-level and couple-level characteristics were significant covariates. Similarities as well as differences are noted between the HRS and AHEAD results. DISCUSSION: Results highlight the importance of dyadic data and multilevel models for understanding depressive symptomatology in married couples. The influence of race/ethnicity merits greater attention in future research. Differences in findings between HRS and AHEAD suggest life-course, cohort, or methodological influences.

Aged↗

PubMed2001

The classification, genetics and neuropathology of frontotemporal dementia. Introduction to the special topic papers: Part I.

Interest in the neuropsychology and neuropsychiatry of frontotemporal dementia (FTD) has escalated in the past decade, as evidenced by the accompanying 10 special topic papers from research groups in the UK, France, North America and Australia addressing a wide range of theoretical and clinical issues. The first part of this review deals with the confusing terminologies that have been used in the area and argues for the retention of the term FTD as the general clinical label, with further subcategorization into the three principal clinical syndromes seen at presentation: frontal variant FTD (often called dementia of frontal type), semantic dementia and progressive non-fluent aphasia. Each of these syndromes has a characteristic profile of presenting clinical features, but may be accompanied by any one of five types of non-Alzheimer pathological change. There have also been significant advances in the genetics of FTD with the identification of tau gene mutations on chromosome 17 in some familial cases. The remarkable story of the discovery of these, the tau gene mutations, is briefly described. Part II of this review (Hodges and Miller, 2001) sets the special issue papers within the context of advances in the neuropsychology of frontal variant FTD and semantic dementia.

Dementia↗

PubMed2001

The neuropsychology of frontal variant frontotemporal dementia and semantic dementia. Introduction to the special topic papers: Part II.

The second part of this review, which accompanies 10 special topic articles dedicated to frontotemporal dementia (FTD), describes some of the advances in understanding frontal variant FTD (fvFTD) and semantic dementia, and the theoretical insights gained into normal cognitive processes from the study of these syndromes. Recent work has clarified the neuropsychiatric features that distinguish fvFTD from Alzheimer's and has begun to spread light on the underlying deficits in social judgement, theory of mind, processing of emotional stimuli and decision making. With regard to central aspects of cognitive processing, such as memory, patients with fvFTD may have a distinctive profile of performance on tests of explicit and implicit memory, and contrary to current views some patients may even have a severe amnesic syndrome. There is also growing evidence that despite relatively well preserved general language skills, patients with fvFTD have particular problems with verb processing. Although there is agreement regarding the key features of semantic dementia, much controversy has surrounded the issue of whether the cognitive findings favour an explanation in terms of progressive breakdown of a central amodal semantic store or differential involvement of verbal and non-verbal systems. Other topics discussed include the impact of semantic breakdown on phonological processes and episodic memory. We also review recent structural and functional neuroimaging findings in semantic dementia.

Dementia↗

PubMed2001

Implementing multiple static field delivery for intensity modulated beams.

A clinically oriented two-dimensional intensity-modulated beam delivery method is implemented using multiple static segmented fields, i.e., the "step-and-shoot" approach. Starting with a desired al" intensity distribution, it creates a multiple-level intensity approximation, and then constructs a sequence of segmented fields to deliver the multiple-level intensities using multileaf collimator (MLC) and independent backup jaws. The approach starts with a simple grouping of all the nonzero intensity values into a minimum number of clusters for a user specified deviation tolerance for the ideal plan. The k-means clustering algorithm is then employed to find the optimal levels of intensity that minimize the discrepancies between the ideal and the approximated intensities, without violating the user specified deviation tolerance. The multiple-level intensities are then decomposed into a sequence of machine deliverable segments. Apart from the first segment for each gantry angle, all the other segments are arranged to minimize the total travel distance of the leaves. The first segment covers the entire irradiated area and is used for treatment verification by electronic portal imaging. The implementation issues due to the physical constraints of the MLCs are also addressed.

Algorithms↗

PubMed2001

Intravenous immunoglobulin therapy for resistant ocular Behçet's disease.

AIMS: The present report was aimed at finding out whether gammaglobulin could have a role in treating ocular Behçet's disease (BD) refractory to accepted medical therapy. METHODS: Six eyes of four patients with ocular BD refractory to steroids and cyclosporin A were treated with a course of intravenous gammaglobulin and followed up for their response to treatment. RESULTS: All six eyes of all four patients showed good response to gammaglobulin therapy. CONCLUSION: Gamma globulin may have a role in treating refractory ocular BD. A wide range of controlled studies with longer follow up is needed to substantiate this impression.

Adolescent↗

PubMed2001

Interleukin-5 inhibition of biliary cell chloride currents and bile flow.

Recent studies have detected significant elevations of interleukin (IL)-5 mRNA in the liver parenchyma of patients with both primary biliary cirrhosis and acute rejection after liver transplantation. In both of these disorders, intrahepatic biliary epithelial cells (BECs) are the targets of injury. We hypothesized that BECs may themselves express IL-5 receptors that may modulate key biliary functions. RNAs coding for IL-5alpha and -beta receptors were amplified by RT/PCR from a biliary cell line derived from a human cholangiocarcinoma (Mz-ChA-1) and verified by DNA sequencing. IL-5 receptor distribution was detected immunocytochemically on Mz-ChA-1 cells, immortalized murine BEC, bile duct-ligated rat liver, and isolated cholangiocytes. Patch-clamp studies on Mz-ChA-1 cells showed that IL-5 inhibits 5'-N-ethylcarboxamidoadenosine-stimulated chloride currents. Additional functional studies showed that IL-5 inhibits secretin-induced bile flow. We conclude that BECs express IL-5 receptors and that IL-5 modulates BEC chloride currents and fluid secretion. Since IL-5 has previously been associated with cholestatic liver disease, we speculate that IL-5 may contribute to liver injury through its effects on biliary secretion.

Animals↗

PubMed2001

Recommended core collection of Web sites for hospital libraries.

Core lists of recommended resources have long been used as selection tools for collection development in hospital libraries. However, hospital librarians now rely on the Internet for access to up-to-date information to supplement materials available within their libraries. Many libraries now either maintain a library Web page or provide input for their institution's Web page. The difficulty is determining what sites to include on their page. This article is a basic guide to recommended links for hospital libraries. It is intended as a starting place for hospital librarians who wish to create (or add to) a Web page of good links to be used for answering reference questions, or as a list for library users. The list is available as a link from the Sharp Health Science Library Web page where it will be updated at least annually. Links will be checked on a regular basis.

Guidelines as Topic↗

PubMed2001

Fluvoxamine treatment of a child with severe PDD: a single case study.

Recent reports suggest that selective serotonin reuptake inhibitors (SSRIs) are useful in the treatment of individuals with autism and other pervasive developmental disorders. We report on a single case study of the use of fluvoxamine with a 7-year-old Caucasian girl with severe pervasive developmental disorder. Our findings indicate that fluvoxamine was significantly effective in reducing stereotypical, repetitive behaviors, anxiety, and aggression and in improving prelinguistic and social behaviors. Our results indicate that the use of the SSRIs as a platform for the long-term habilitation of these children should be considered, but further studies are required to establish the efficiency of fluvoxamine for the treatment of children with autism.

Child↗

PubMed2001

Safety and efficacy of short-duration oral terbinafine for the treatment of tinea corporis or tinea cruris in subjects with HIV infection or diabetes.

Cutaneous fungal infections in immunocompromised patients can be aggressive and difficult to treat. To determine the safety and efficacy of oral terbinafine for the treatment of tinea corporis or tinea cruris in subjects with human immunodeficiency virus (HIV) infection or diabetes, 2 prospective, randomized, open-label studies were conducted in general community and referral centers. HIV-positive (n = 6) and diabetic patients (n = 8) between the ages of 18 and 75 years diagnosed with either tinea corporis or tinea cruris, as confirmed by potassium hydroxide (KOH) wet mount microscopy, were randomized to receive either 1 or 2 weeks of the antifungal treatment. Patients received oral terbinafine 250 mg once daily for 1 or 2 weeks. Main outcome measures were mycological cure, determined at week 6 for HIV-positive and diabetic patients. Three subjects were excluded from the efficacy analyses because of negative cultures at screening (n = 2) and lack of follow-up cultures (n = 1). Efficacy results were similar between the 1- and 2-week groups in both studies. All HIV-positive subjects and 83% of diabetic subjects achieved mycological cures at week 6 based on culture results. In a safety population that included all randomized patients (N = 14), no subject experienced adverse events or significant changes in laboratory findings related to study medication. Results of these small series indicate that a short course of oral terbinafine 250 mg once daily is a safe and effective treatment for tinea corporis or tinea cruris in subjects with HIV infection or diabetes.

AIDS-Related Opportunistic Infections↗