Search PubMed⌕ Search

Biomedical subjects

C Young

Publications and source records attributed to C Young.

At least 55 records · Page 3Linked to original sources

The safety and efficacy of a two-dose daclizumab (zenapax) induction therapy in liver transplant recipients.

BACKGROUND: Induction therapy with daclizumab has been shown to be efficacious in the prevention of acute rejection in kidney transplant patients. The routine use of antibody induction therapy in liver transplantation has not gained widespread acceptance, except in the cases of renal insufficiency. The recent approval of daclizumab prompted us to initiate this pilot study using induction therapy in those patients at risk for developing posttransplant renal insufficiency. METHODS: This nonrandomized study examined the use of daclizumab in 39 of the last 97 liver transplants performed at the University of Alabama in Birmingham. The daclizumab group received 2 mg/kg intravenously before organ engraftment, and 38 of the 39 received 1 mg/kg intravenously on postoperative day 5. The control group consisted of the remaining 58 contemporary patients. Additional immunosuppression consisted of steroids, tacrolimus, or microemulsion cyclosporine in all patients and mycophenolate mofetil in selected patients. RESULTS: Pretransplant demographics were not significantly different between the groups. In the induction group there were significantly fewer males, 14 (36%) vs. 34 (59%) (P=0.03). They had greater renal insufficiency at the time of transplant, serum creatine 1.9+/-0.37 mg/dl vs. 0.8+/-0.5; P=0.0009, and more patients were at higher acuity (status 1 and 2A): 12 (31%) vs. 3 (5%) P=0.0006 than in the noninduction group. By postoperative day 7, renal function improved in the induction group such that it was not significantly different from the noninduction group and remained similar throughout the rest of the follow-up. The induction group also experienced significantly less acute rejection, 7 (18%) vs. 23 (40%) (P=0.02) than in the noninduction group in the first 6 months. The 1-, 3-, and 6-month patient survival rates were similar in the induction group, 97.4%, 97.4%, and 97.4%, vs. non-induction 94.8%, 93.0%, and 93% (P=NS). The incidence of cytomegalovirus, in the first 6 months, in the induction group was four (10%) vs. five (9%) (P=NS) in the noninduction group. CONCLUSION: In the pilot study, induction therapy with daclizumab was safe, facilitated improvement in renal function, and appeared to reduce the incidence of acute rejection. Combination therapy with daclizumab may be an important adjunct in immunosuppressive strategies for liver transplant recipients.

Adult↗

Rab37 is a novel mast cell specific GTPase localized to secretory granules.

GTPases regulate a myriad of cellular functions including signal transduction, cytoskeletal organization and membrane trafficking. Rab GTPases act to coordinate the membrane dynamics of cells by organizing and regulating the activity of effector proteins important in vesicle trafficking. Rab37 is a novel Rab GTPase specifically expressed in the MC-9 mast cell line and bone marrow mast cells. Rab37 is 74% identical to Rab26 and 47% identical to Rab8, a GTPase important in Golgi to plasma membrane vesicle trafficking in mammalian cells. When green fluorescent protein tagged Rab37 is expressed in bone marrow mast cells, the secretory granules are labeled. These data suggest that Rab37 may play an important role in mast cell degranulation making this protein a potentially important target for therapeutic intervention in the treatment of allergy.

Amino Acid Sequence↗

Glutathione S-transferase polymorphisms in MS: their relationship to disability.

BACKGROUND: Oxidative stress has been implicated in inflammatory demyelination. The glutathione S-transferase (GST) supergene family encodes isoenzymes that appear to be critical in protection against oxidative stress. Certain GST loci are polymorphic, demonstrating alleles that are null (GSTM1/GSTT1), encode low activity variants (GSTP1), or are associated with variable inducibility (GSTM3). OBJECTIVES: To investigate the association between clinical outcome in MS and allelic variants of GSTM1, GSTM3, GSTT1, and GSTP1. METHODS: Four hundred patients with clinically definite MS were studied. Disability was measured using the Kurtzke Expanded Disability Status Scale (EDSS). Disability was graded as mild (EDSS 0-4), moderate (4.5-5.5), or severe (EDSS 6-10). PCR-based genotyping was performed using DNA extracted from lymphocytes. Significant associations between GST genotypes and clinical outcome were corrected for gender, onset age, and disease duration using logistic regression. RESULTS: We found that the GSTM3 AA genotype was associated with severe disability in patients with a disease duration of more than 10 years (p = 0.027, n = 177, OR = 2.4, 95% CI = 1.1-5.0). Homozygosity for both GSTM1*0 and GSTP1*Ile105 containing allele was associated with severe disability in patients with a disease duration greater than 10 years (p = 0.022, n = 179, OR = 5.0, 95% CI = 1.3-19.8). CONCLUSIONS: Our results suggest that long-term prognosis in MS is influenced by a genetically determined ability to remove the toxic products of oxidative stress.

Adult↗

Docosahexaenoic acid inhibits synaptic transmission and epileptiform activity in the rat hippocampus.

Docosahexaenoic acid (DHA) has been suggested to be required for neuronal development and synaptic plasticity. However, in view of the fact that DHA facilitates NMDA responses and blocks K(+) channels, it might predispose the neurons to epileptiform bursting. By using extracellular recording of population spikes in the CA1 region of rat hippocampal slices, we tested this possibility by examining the effect of DHA on the epileptiform activity induced by bicuculline or in Mg(2+)-free medium. When stimuli were delivered to the Schaffer collateral/commissural pathway every 20 or 30 sec, DHA had no significant effect on the epileptiform activity. However, when the frequency of stimulation was increased to 0.2 Hz, DHA attenuated the amplitude of the bursting activity induced by bicuculline to 57.5+/- 10.8% and those induced by Mg(2+)-free ACSF to 65.8+/-13.9% of control. DHA reduced the slope of field excitatory postsynaptic potential (fEPSP) to 77.1+/-7.4% of baseline, without significant effect on the ratio of paired-pulse facilitation (PPF). By intracellular recording of neurons in the stratum pyramidale of rat hippocampal slices, we found that DHA markedly inhibited the repetitive firing of action potentials elicited by depolarizing current pulses but did not affect the initial action potential. Thus, DHA may attenuate epileptic activity mainly through the frequency-dependent blockade of Na(+) channels.

Action Potentials↗

Anti-spasticity agents for multiple sclerosis.

BACKGROUND: Spasticity is a common problem in MS patients causing pain, spasms, loss of function and difficulties in nursing care. A variety of oral and parenteral medications are available. OBJECTIVES: To assess the absolute and comparative efficacy and tolerability of anti-spasticity agents in multiple sclerosis (MS) patients. SEARCH STRATEGY: Randomised controlled trials (RCTs) of anti-spasticity agents were identified using MEDLINE, EMBASE, bibliographies of relevant articles, personal communication, manual searches of relevant journals and information from drug companies. SELECTION CRITERIA: Double-blind, randomised controlled trials (either placebo-controlled or comparative studies) of at least seven days duration. DATA COLLECTION AND ANALYSIS: Two independent reviewers extracted data and the findings of the trials were summarised. Missing data were collected by correspondence with principal investigators. A meta-analysis was not performed due to the inadequacy of outcome measures and methodological problems with the studies reviewed. MAIN RESULTS: Twenty-three placebo-controlled studies (using baclofen, dantrolene, tizanidine, botulinum toxin, vigabatrin, prazepam and threonine) and thirteen comparative studies met the selection criteria. Only thirteen of these studies used the Ashworth scale, of which only three of the six placebo-controlled trials and none of the seven comparative studies showed a statistically significant difference between test drugs. Spasms, other symptoms and overall impressions were only assessed using unvalidated scores and results of functional assessments were inconclusive. REVIEWER'S CONCLUSIONS: The absolute and comparative efficacy and tolerability of anti-spasticity agents in multiple sclerosis is poorly documented and no recommendations can be made to guide prescribing. The rationale for treating features of the upper motor neurone syndrome must be better understood and sensitive, validated spasticity measures need to be developed.

Anti-Dyskinesia Agents↗

Famciclovir in chronic hepatitis B: results of a dose-finding study.

BACKGROUND/AIMS: Famciclovir, an orally available nucleoside analogue with potent in vitro activity against HBV, is being investigated for treatment of chronic hepatitis B. METHODS: A dose-finding study was conducted in patients with hepatitis B e antigen present in serum. Patients received famciclovir 125 mg, 250 mg, 500 mg three times daily (tid) or placebo for 16 weeks, followed by 8 months post-treatment observation, and 16 weeks open-label treatment. More than 90% of patients had previously received alpha-interferon or had baseline characteristics indicating a high likelihood of poor response to alpha-interferon. RESULTS: Famciclovir induced rapid, dose-dependent suppression of viral replication and reduction in alanine aminotransferase (ALT), with greatest efficacy in the 500-mg tid treatment group. HBV DNA reduction was maintained throughout the treatment period. ALT also steadily declined during the treatment period. Approximately 40% of patients with pretreatment ALT>upper limit of normal (ULN) receiving famciclovir 500 mg tid, experienced sustained normalization of ALT at the end of the 8-month follow-up. Anti-HBe seroconversion occurred more frequently in patients receiving famciclovir 500 mg tid compared with placebo (p=0.04). Famciclovir was generally well tolerated; the incidence of adverse events was comparable to placebo. Exacerbation of liver disease or serious ALT flares were not observed. CONCLUSION: Famciclovir 500 mg three times daily may offer an alternative to alpha-interferon for treatment for chronic hepatitis B. Anti-HBe seroconversion in the famciclovir 500-mg tid group suggests that 16 weeks treatment has the potential for HBV clearance. Further studies with a longer treatment duration are warranted.

2-Aminopurine↗

Epidermal nevus syndrome with hypermelanosis and chronic hyponatremia.

Epidermal nevus syndrome is seldom encountered, and its association with hypermelanosis and the chronic syndrome of inappropriate antidiuretic hormone secretion (SIADH) has never been reported. A male neonate who developed intractable seizures and hyponatremia soon after birth is reported. He had alopecic patches on the scalp at birth. Large areas of skin hyperpigmentation, and epidermal nevi developed gradually. The clinical picture of hypotonic hyponatremia, high urine osmolality, elevated urine sodium, and euvolemia was compatible with SIADH. The seizures did not correlate with the hyponatremia, and no other cause for the seizures could be identified. The hyponatremia became chronic and was treated with a direct supply of sodium chloride. The development of the patient was markedly delayed at the last visit when he was 1 year of age. It is suggested that hypermelanosis and chronic SIADH may also be a variant presentation of epidermal nevus syndrome.

Brain↗

A randomized, placebo-controlled study to evaluate the efficacy of 12-month famciclovir treatment in patients with chronic hepatitis B e antigen-positive hepatitis B.

We conducted a randomized, placebo-controlled clinical study evaluating famciclovir (500 mg 3 times daily and 1.5 g once daily) for 1 year (6 months post-treatment follow-up) in patients with chronic hepatitis B e antigen (HBeAg)-positive hepatitis B virus (HBV) infection. The study was conducted in 80 centers in North America, Europe, and Australia/New Zealand. A total of 417 patients with histologically documented chronic hepatitis B (histologic activity index [HAI] 9.5-11.0) received famciclovir (500 mg 3 times daily or 1.5 g once daily) or placebo. Famciclovir 500 mg 3 times daily significantly reduced HBV DNA and median HAI scores versus placebo. By week 8, median HBV DNA decreased from 1,645 to 283 MEq/mL (famciclovir 500 mg 3 times daily) and from 1,147 to 304 MEq/mL (famciclovir 1.5 g once daily), while increasing for placebo (1,617 to 1,685 MEq/mL). Median change in HBV DNA at the end of therapy was -76% (famciclovir 500 mg 3 times daily; P <.01) and -60% (famciclovir 1.5 g once daily; P =.25) versus -37% for placebo. Median change in HAI was -1.5 points (famciclovir 500 mg 3 times daily; P =.02) and -1.0 point (famciclovir 1.5 g once daily; P =.35) and zero for placebo. Fifty percent of patients receiving famciclovir 500 mg 3 times daily (P =.07) and 43% receiving 1.5 g once daily (P =.41) experienced >/=2 points improvement in HAI versus 37% for placebo. Nine percent of patients treated with famciclovir 500 mg 3 times daily underwent anti-HBeAg seroconversion with undetectable HBV DNA at end of follow-up versus 3% in the placebo group (P =.05). Famciclovir was well tolerated; the incidence of post-treatment alanine transaminase (ALT) elevations was comparable with placebo. In conclusion, famciclovir 500 mg 3 times daily gave modest suppression of viral replication, but translated into significant histologic improvement in median HAI score at 1 year.

2-Aminopurine↗

Gestational diabetes screening in subsequent pregnancies of previously healthy patients.

OBJECTIVE: Our purpose was to evaluate women without gestational diabetes mellitus in an index pregnancy for the likelihood that gestational diabetes would develop and for risk factors for carbohydrate intolerance in a subsequent pregnancy. STUDY DESIGN: A retrospective review of medical records at a teaching hospital universally screening for gestational diabetes identified multiparous women who had been delivered twice between 1994 and 1997 and who, in the first (index) pregnancy, had had a normal result on a screening test with 50 g of glucose used in a "glucola" beverage (< or =140 mg/dL). RESULTS: In this population with normal glucose screening values in the index pregnancy, 352 (92.4%) of 381 women had at least one risk factor for gestational diabetes. However, none of the 381 women had gestational diabetes in the subsequent pregnancy (0/381, 95% confidence interval < or =1%), including 45 (12. 4%) who had an abnormal result on the 50-g glucose screening test. Regression analysis showed this test result in the index pregnancy (P =.001) to be the only studied variable significantly associated with the 50-g glucose value in the subsequent pregnancy. CONCLUSION: Despite a high rate of risk factors for gestational diabetes, women in our population with a normal glucose value in an index pregnancy have a minimal risk (<1%) that gestational diabetes will develop in a subsequent singleton pregnancy within 4 years. This factor may be included in determining whether women should undergo screening for gestational diabetes.

Adolescent↗

Sjögren's syndrome, cavitating lung disease and high sustained levels of antibodies to serine proteinase 3.

A case is described involving Sjögren's syndrome, high sustained levels of antibodies to serine proteinase 3, and cavitating lung disease. Possible diagnoses accounting for this unusual combination include a novel association of Sjögren's syndrome and Wegener's granulomatosis (suggested by the high and sustained levels of antibodies to serine proteinase 3) or a rare presentation of bronchiolitis obliterans organising pneumonia. Identification of the true nature of the patients illness facilitated more active management and a swift resolution of the clinical problem.

Aged↗

Calcium metabolism in sarcoidosis and its clinical implications.

OBJECTIVE: : To examine the clinical implications of disturbed calcium metabolism in sarcoidosis and how the pathophysiology affects management strategies. METHODS: : The literature concerning calcium metabolism in sarcoidosis was reviewed. RESULTS: : Dysregulated calcium metabolism is a well-recognized complication of sarcoidosis, resulting in hypercalcaemia (prevalence 5-10%), hypercalcuria (40-62%) and reduced bone density (40-55%). Extrarenal synthesis of calcitriol [1,25(OH)(2)D(3)] is central to the pathogenesis of abnormal calcium homeostasis, but alterations in parathyroid hormone (PTH) activity and the expression of PTH-related peptide have also been demonstrated. The immunosuppressive properties of calcitriol suggest that the raised levels seen in sarcoidosis could represent an adaptive response to the undefined antigen that causes sarcoidosis. CONCLUSIONS: : The mechanisms of abnormal calcium metabolism in sarcoidosis need to be understood when treating hypercalcaemia, hypercalcuria and corticosteroid-induced osteoporosis. Studies are required to determine if the currently available therapies for osteoporosis are safe and effective in sarcoidosis.

Calcium↗

Sedation in the intensive care unit.

OBJECTIVE: To describe the goals of sedative use in the intensive care unit and review the pharmacology of commonly used sedative drugs as well as to review pertinent publications in the literature concerning the comparative pharmacology of these drugs, with emphasis on outcomes related to sedation and comparative pharmacoeconomics. DATA SOURCES: Publications in the scientific literature. DATA EXTRACTION: Computer search of the literature with selection of representative articles. SYNTHESIS: Proper choice and use of sedative drugs is based on knowledge of the pharmacology of commonly used agents and is an essential component of caring for patients in the intensive care unit. The large variability in pharmacokinetics and pharmacodynamics in the critically ill make it difficult to directly compare agents. Midazolam provides rapid and reliable amnesia, even when administered for low levels of sedation. Propofol may be useful when deeper levels of sedation and more rapid awakening are required. Lorazepam can be used for long-term sedation in more stable patients if rapidity of effect is not required. Further investigation in assessment of depth of sedation in the critically ill is needed. Continued study of costs, side effects, and appropriate dosing strategies of all sedative agents is needed to answer questions not sufficiently addressed in the current literature. CONCLUSION: An individualized approach to sedation based on knowledge of drug pharmacology is needed because of confounding variables including concurrent patient illness, depth of sedation, and concomitant use of analgesic agents. (Crit Care Med 2000; 28:854-866)

Decision Making↗

Polymorphisms of apolipoprotein E; outcome and susceptibility in multiple sclerosis.

Allelic variants of the apolipoprotein E (APOE) gene influence the course of several neurological diseases. In multiple sclerosis the concentration of APOE in cerebrospinal fluid and its intrathecal synthesis is reduced. Specific isoforms of APOE may also be important and it has been suggested that possession of the epsilon4 allele may be associated with a more aggressive disease process. These data prompted us to re-examine, in a large group of patients with multiple sclerosis, the proposal that allelism in the apolipoprotein gene influences disease course. Genotypes were determined in a well-defined group of 370 unrelated Caucasians with clinically definite multiple sclerosis and in 159 healthy controls. Age at onset, sex, disease duration, disease subtype were recorded. Disability was measured using the Kurtzke expanded disability status score in patients with a disease duration of 10 years or greater. There was no significant difference in APOE allele or genotype frequencies between patients and controls, between disease subtypes or between genders. APOE genotype did not significantly influence age of onset, and no significant relationship between genotype, allele frequency and disease severity was found. This study suggests that individual APOE alleles or genotypes do not determine disease susceptibility or the clinical course of multiple sclerosis.

Adult↗

Gemifloxacin versus amoxicillin/clavulanate in the treatment of acute exacerbations of chronic bronchitis. The 070 Clinical Study group.

Six hundred patients were evaluated in this randomized, double-blind, double-dummy, multicenter, parallel-group study comparing the efficacy and safety of gemifloxacin (320 mg once-daily for 5 days) and amoxicillin/clavulanate (500/125 mg three-times daily for 7 days) for the treatment of acute exacerbations of chronic bronchitis (AECB). Of note, more than 90% of study participants had stage 2 disease at study entry. The two drugs were found to be equally effective, with clinical success rates of 93.6% for gemifloxacin and 93.2% on amoxicillin/clavulanate (95% CI -3.9 to 4.6). Bacteriological success rates favored gemifloxacin (90.9% compared with 79.5% for amoxicillin/clavulanate; 95% CI -3.3 to 26.0); however, this difference was not statistically significant. Gemifloxacin and amoxicillin/clavulanate were both well tolerated. In summary, gemifloxacin was found to be well tolerated and effective for the treatment of AECB, suggesting it is well suited for empirical treatment of this common respiratory condition in the current clinical environment.

Acute-Phase Reaction↗

Patterns of allelic loss at the BRCA1 locus in Arabic women with breast cancer.

Loss of heterozygosity (LOH) of BRCA1, a tumor suppressor gene, is one mechanism of genetic inactivation in both sporadic and familial forms of breast cancer. Studies reported in breast cancers from women of Northern European descent have shown LOH in 30-50% of sporadic tumors. Microsatellite instability (MSI) has served as evidence for involvement of DNA repair genes. This study investigates the extent of allelic imbalance at the BRCA1 region in Arabic women with breast cancer. Paired normal and tumor tissue were available for DNA analysis in 13 cases. Results using fluorescent tagged primers to microsatellite markers D17S1323, D17S1325 and D17S855 intragenic to BRCA1 were analyzed using an ABI 310 DNA sequencer. As compared to normal DNA, MSI and LOH were recognized as a gain and a loss, respectively, of one signal in one allele in the tumor DNA. Microsatellite analyses showed 12 of 13 (92%) cases with LOH or MSI or both. Three cases demonstrated LOH alone, 3 cases with MSI alone. Six cases indicated both LOH and MSI; 2 cases with either LOH or MSI in separate markers. The combined finding of LOH and MSI in the same marker was detected only with D17S1325 in 4/6 cases. The proportion of aberrant findings of the BRCA1 locus in breast cancer appears to be higher in Arabic women than in other populations studied to date.

Adult↗

Liver transplantation in the era of cost constraints.

BACKGROUND: The issue of containing cost has had a significant impact on organ transplantation. After our institution's 500th liver transplant, we critically examined the impact of the changing health care environment on liver transplantation. METHODS: We retrospectively analyzed 500 consecutive liver transplants done in the period of 1989 to 1998. RESULTS: Comparing the first 100 liver transplants to the last 100, patient demographics did not change significantly; however, mean waiting times increased significantly, from 30.4 days to 146.7 days, and median hospital stay decreased from 20.2 days to 10.9 days. One-year patient and graft survivals were not significantly different, 93.6% versus 96.5% and 88.0% versus 95.7%, respectively. CONCLUSIONS: Despite transplants in patients at higher risk and discharging patients sooner after transplantation, surgical results and patient survivals remained excellent. This was accomplished through improvements and modification of immunosuppression, outpatient treatment of uncomplicated acute rejection, and emphasis on close outpatient follow-up.

Alabama↗