Human leukocyte antigen class-I variation is associated with atopic dermatitis: A case-control study.

Atopic dermatitis (AD) is a common immune-medicated skin disease. Previous studies have explored the relationship between Human Leukocyte Antigen (HLA) allelic variation and AD with conflicting results. The aim was to examine HLA Class I genetic variation, specifically peptide binding groove variation, and associations with AD. A case-control study was designed to evaluate HLA class I allelic variation and binding pocket polymorphisms, using next generation sequencing on 464 subjects with AD and 388 without AD. Logistic regression was used to evaluate associations with AD by estimating odds ratios (95% confidence intervals). Significant associations were noted with susceptibility to AD (B*53:01) and protection from AD (A*01:01, A*02:01, B*07:02 and C*07:02). Evaluation of polymorphic residues in Class I binding pockets revealed six amino acid residues conferring protection against AD: A9F (HLA-A, position 9, phenylalanine) [pocket B/C], A97I [pocket C/E], A152V [pocket E], A156R [pocket D/E], B163E [pocket A] and C116S [pocket F]. These findings demonstrate that specific HLA class I components are associated with susceptibility or protection from AD. Individual amino acid residues are relevant to protection from AD and set the foundation for evaluating potential HLA Class I molecules in complex with peptides/antigens that may initiate or interfere with T-cell responses.

Outcomes of endoscopically harvested saphenous vein for lower extremity bypass.

OJECTIVES: The purpose of this study was to evaluate the outcomes of endoscopically harvested saphenous vein (EHSV) for lower extremity bypass (LEB) surgery. METHODS: Data from 91 consecutive patients who underwent LEB using EHSV between February 2003 and November 2012 were analyzed. Outcomes of interest were wound infection, patency, re-intervention and limb loss. RESULTS: Fifty-eight (64%) and 33 (36%) patients underwent femoropopliteal (FP) and femorotibial (FT) bypass using EHSV. Three (3%) patients had superficial and 1 (1%) deep wound infection. Primary and primary assisted patency at 5 years was 68% and 71% in the FP group and 56% and 65% in the FT group. Six (6%) patients underwent major amputation. No predicting factors for wound infection or graft patency were found. CONCLUSIONS: EHSV carries a low incidence of perioperative wound complication and has a reasonable mid-to-long-term patency regardless of the length of vein harvested.

Dermacentor andersoni transmission of Francisella tularensis subsp. novicida reflects bacterial colonization, dissemination, and replication coordinated with tick feeding.

Ticks serve as biological vectors for a wide variety of bacterial pathogens which must be able to efficiently colonize specific tick tissues prior to transmission. The bacterial determinants of tick colonization are largely unknown, a knowledge gap attributed in large part to the paucity of tools to genetically manipulate these pathogens. In this study, we demonstrated that Francisella tularensis subsp. novicida, for which a complete two-allele transposon mutant library has been constructed, initially infects the midguts of 100% of acquisition-fed Dermacentor andersoni nymphs, with stable colonization and replication during a subsequent molt. Increased dissemination to and marked replication within the salivary gland was closely linked to a second (transmission) feed and culminated in secretion of bacteria into the saliva and successful transmission. Simultaneous testing of multiple mutants resulted in total bacterial levels similar to those observed for single mutants. However, there was evidence of a bottleneck during colonization, resulting in a founder effect in which the most successful mutant varied when comparing individual ticks. Thus, it is essential to assess mutant success at the level of the tick population rather than in individual ticks. The ability of F. tularensis subsp. novicida to recapitulate the key physiological events by which bacteria colonize and are transmitted by ixodid ticks provides a new genome-wide approach to identify the required pathogen molecules and pathways. The identification of specific genes and, more importantly, conserved pathways that function at the tick-pathogen interface will accelerate the development of new methods to block transmission.

Temozolomide single-agent chemotherapy for newly diagnosed anaplastic oligodendroglioma.

The treatment of patients with anaplastic oligodendroglioma (AO) has been significantly impacted by the molecular detection of loss of sequences on chromosomes 1p and 19q. We performed a clinical trial to prospectively evaluate the safety of treating patients with AO with temozolomide (TMZ) alone in patients with chromosome 1p/19q loss and with chemo-radiation in patients not harboring this loss. Forty-eight patients were enrolled, 36/48 (75%) with evidence of chromosome 1p/19q loss treated with TMZ alone and 12/18 (25%) without such losses, treated with pre-radiation TMZ followed by chemo-radiation. Despite more aggressive treatment, patients without 1p/19q loss had a shorter progression-free survival (PFS) of 13.5 months. With a median follow-up time of 32 months, patients with 1p/19q LOH had a median TTP of 28.7 months. Patients with AO with 1p/19q LOH can be safely treated with single-agent TMZ and do not appear to experience earlier or more frequent tumor progression. This treatment regimen should be studied as part of a formal randomized clinical trial.

Dominant non-coding repeat expansions in human disease.

The general model that dominant diseases are caused by mutations that result in a gain or change in function of the corresponding protein was challenged by the discovery that the myotonic dystrophy type 1 mutation is a CTG expansion located in the 3' untranslated portion of a kinase gene. The subsequent discovery that a similar transcribed but untranslated CCTG expansion in an intron causes the same multisystemic features in myotonic dystrophy type 2 (DM2), along with other developments in the DM1 field, demonstrate a mechanism in which these expansion mutations cause disease through a gain of function mechanism triggered by the accumulation of transcripts containing CUG or CCUG repeat expansions. A similar RNA gain of function mechanism has also been implicated in fragile X tremor ataxia syndrome (FXTAS) and may play a role in pathogenesis of other non-coding repeat expansion diseases, including spinocerebellar ataxia type 8 (SCA8), SCA10, SCA12 and Huntington disease-like 2.

Marjolin's ulcer arising at the elbow: a case report and literature review.

Marjolin's ulcer is a squamous cell carcinoma that develops in posttraumatic scars and chronic wounds. It was first noted to be associated with chronic osteomyelitis in 1835 and is usually described occurring in lower extremity wounds. Suspicion of such lesions should be raised in chronic wounds demonstrating characteristic changes. Impaired immunologic activity in chronic wounds has also been shown to contribute to the pathologic process. Definitive treatment in the past has been amputation proximal to the tumor, however; recently, wide resection and radiation therapy have been used. According to Lifeso et al., wide local excision is unreliable and they recommend amputation in grade II or III disease and wide local excision in very small lesions that can be radically excised or in grade I lesions. We report a case of a Marjolin ulcer that developed at the elbow. Physicians should have a high index of suspicion in chronic wounds that are recalcitrant to therapy and should remember to biopsy all suspected lesions. Early recognition and definitive treatment are the mainstays ensuring the best prognosis.

Weight loss and malnutrition in patients with chronic graft-versus-host disease.

It is well known that weight loss occurs in patients with chronic graft-versus-host disease. However, the severity and frequency of weight loss in this population have not been adequately described. Recent data suggest that a body-mass index (BMI) below 21.9 is an independent risk factor for mortality. In our analysis we have shown that out of 93 patients with cGVHD, 43% are malnourished as evidenced by a BMI less than 21.9 and 14% are severely malnourished (BMI less than 18.5). In addition, there is a clear trend showing that patients with active, ongoing cGVHD have lower BMIs (P = 0.02). Furthermore, we show that many symptoms thought to contribute to weight loss in patients with cGVHD, such as odynophagia and oral sensitivity, are not related to weight loss in our population. We conclude that, in all likelihood, unknown causes still exist that are responsible for weight loss in this group of patients. Elevated resting energy expenditure and elevated serum tumor necrosis factor-alpha are potential contributors to weight loss that will be tested in future studies. We also conclude that treating cGVHD aggressively may help reverse weight loss and malnutrition, which may be independent risk factors for mortality in this population.

Pancreatic insufficiency in patients with chronic graft-versus-host disease.

Diarrhea is a difficult diagnostic problem in patients with chronic graft-versus-host disease (cGVHD) because there are many causes of it. Although intestinal involvement has been reported in early studies of untreated cGVHD, this is now a very rare presentation of the disease. In addition to other etiologies, pancreatic insufficiency should also be considered in patients with cGVHD who demonstrate malabsorption. The pathogenesis of pancreatic insufficiency in these patients is unknown. Pancreatic enzyme supplements can be very effective in treating this rare condition.

Development of a prognostic model for grading chronic graft-versus-host disease.

The disease-specific survival (DSS) of 151 patients with chronic graft-versus-host disease (cGVHD) was studied in an attempt to stratify patients into risk groups and to form a basis for a new grading of cGVHD. The data included the outcome and 23 variables at the diagnosis of cGVHD and at the primary treatment failure (PTF). Eighty-nine patients (58%) failed primary therapy for cGVHD. Nonrelapse mortality was 44% after a median follow-up of 7.8 years. The probability of DSS at 10 years after diagnosis of cGVHD (DSS1) and after PTF (DSS2) was 51% (95% confidence interval [CI] = 39%, 60%) and 38% (95% CI = 28%, 49%), respectively. According to multivariate analysis, extensive skin involvement (ESI) more than 50% of body surface area; hazard ratio (HR) of 7.0 (95% CI = 3.6-13.4), thrombocytopenia (TP) (< 100 000/microL; HR, 3.6; 95% CI = 1.9-6.8), and progressive-type onset (PTO) (HR, 1.7; 95% CI = 0.9-3.0) significantly influenced DSS1. These 3 factors and Karnofsky Performance Score of less than 50% at PTF were significant predictors for DSS2. The DSS1 at 10 years for patients with prognostic factor score (PFS) at diagnosis of 0 (none), 1.9 and below [corrected] (ESI only or TP and/or PTO), above 1.9 and not above 3.5 [corrected] (ESI plus either TP or PTO), and more than 3.5 (all 3 factors) was 82%, 68%, 34%, and 3% (P =.05, <.001, <.001), respectively. The DSS2 at 5 years for patients with PFS at PTF of 0, 2 or less, 2 to 3.5, and more than 3.5 were 91%, 71%, 22%, and 4% (P =.2,.005, and <.001), respectively. It was concluded that these prognostic models might be useful in grouping the patients with similar outcome.

Clinical and angiographic outcome in the laser angioplasty for restenotic stents (LARS) multicenter registry.

In-stent restenosis (ISR), when treated with balloon angioplasty (PTCA) alone, has an angiographic recurrence rate of 30%-85%. Ablating the hypertrophic neointimal tissue prior to PTCA is an attractive alternative, yet the late outcomes of such treatment have not been fully determined. This multicenter case control study assessed the angiographic and clinical outcomes of 157 consecutive procedures in 146 patients with ISR at nine institutions treated with either PTCA alone (n = 64) or excimer laser assisted coronary angioplasty (ELCA, n = 93)) for ISR. Demographics were similar except more unstable angina at presentation in ELCA-treated patients (74.5% vs. 63.5%; P = 0.141). Lesions selected for ELCA were longer (16.8 +/- 11.2 mm vs. 11.2 +/- 8.6 mm; P < 0.001), more complex (ACC/AHA type C: 35.1% vs. 13.6%; P < 0.001), and with compromised antegrade flow (TIMI flow < 3: 18.9% vs. 4.5%; P = 0.008) compared to PTCA-treated patients. ELCA-treated patients had similar rate of procedural success [93 (98.9% vs. 62 (98.4%); P = 1.0] and major clinical complications [1 (1.1%) vs. 1 (1.6%); P = 1.0]. At 30 days, repeat target site coronary intervention was lower in ELCA-treated patients (1.1% vs. 6.4% in PTCA-treated patients; P = 0.158), but not significantly so. At 1 year, ELCA-treated patients had similar rate of major cardiac events (39.1% vs. 45.2%; P = 0.456) and target lesion revascularization (30.0% vs. 32.3%; P = 0.646). These data suggest that ELCA in patients with complex in-stent restenosis is as safe and effective as balloon angioplasty alone. Despite higher lesion complexity in ELCA-treated patients, no increase in event rates was observed. Future studies should evaluate the relative benefit of ELCA over PTCA alone for the prevention of symptom recurrence specifically in patients with complex in-stent restenosis.

New approaches to treating malignances with stem cell transplantation.

Stem cell transplantation has been successfully used to treat a wide variety of hematologic malignancies. New and exciting strategies being developed for use in conjunction with transplant will be useful in overcoming tumor resistance. It is now clear that a significant part of the antitumor effect of allogeneic stem cell transplantation is derived from the graft itself and is independent of the preparative regimen. Immune therapy derived from the donor's graft is uniquely suited for killing chemoresistant tumor cells and may prove to be an invaluable tool for decreasing the risk of relapse in patients with advanced disease. Among patients who have relapsed after allogeneic bone marrow transplantation (BMT), an immunologically based antitumor effect may be obtained simply by transfusing T cells obtained by leukopheresis of the original bone marrow donor. Referred to as donor leukocyte infusion (DLI), this technique has been used to obtain complete remissions in relapsed acute myeloid leukemia (AML), acute lymphocytic leukemia (ALL), multiple myeloma, non-Hodgkin's lymphoma, myelodysplastic syndrome (MDS), and chronic myeloid leukemia (CML). Another approach that uses the donor's graft to obtain a potent antitumor effect is the combination of nonmyeloablative BMT followed by immunotherapy with DLI. Numerous investigators are exploring ways of combining autologous BMT with immune therapy. Animal studies using tumor vaccines in conjunction with autologous transplantation offer a promising method for eliminating tumor. Patients undergoing autologous transplantation may have marrow that has been contaminated with tumor, which places them at a higher risk of relapse. Attempts have been made to eliminate contaminating tumor from the marrow by purging.

Adenoviral vector-mediated rescue of the OMP-null phenotype in vivo.

The use of gene deletion by homologous recombination to determine gene or protein function has wide application in vertebrate neurobiology. An ideal complement to gene deletion would be subsequent gene replacement to demonstrate re-acquisition of function. Here we used an adenoviral vector to replace the olfactory marker protein (OMP) gene in olfactory receptor neurons of adult OMP-null mice and demonstrated the subsequent re-acquisition of function. Our results show that short-term expression of OMP restores the kinetics of electrophysiological responses of OMP-null mice to those of the control phenotype. This adenoviral-mediated rescue of the OMP-null phenotype is consistent with involvement of OMP in olfactory transduction.

(R)-, (S)-, and racemic fluoxetine N-demethylation by human cytochrome P450 enzymes.

Fluoxetine is one of the most widely prescribed selective serotonin reuptake inhibitors (SSRIs) that is marketed worldwide. However, details of its human hepatic metabolism have been speculative and incomplete, possibly due to the sensitivity of analytical techniques and selectivity of specific in vitro probes and reagents used. Studies with (R)-, (S)-, and racemic fluoxetine were undertaken to determine the stereospecific nature of its metabolism and estimate intrinsic clearance contributions of each CYP for fluoxetine N-demethylation. Measurable fluoxetine N-demethylase activity was catalyzed by CYP1A2, -2B6, -2C9, -2C19, -2D6, -3A4, and -3A5. All enzymes catalyzed this reaction for both enantiomers and the racemate, and intrinsic clearance values were similar for the enantiomers for all CYP enzymes except CYP2C9, which demonstrated stereoselectivity for R- over the S-enantiomer. Scaling the intrinsic clearance values for the individual CYP enzymes to estimate contributions of each in human liver microsomes suggested that CYP2D6, CYP2C9, and CYP3A4 contribute the greatest amount of fluoxetine N-demethylation in human liver microsomes. These data were corroborated with the examination of the effects of CYP-specific inhibitors quinidine (CYP2D6), sulfaphenazole (CYP2C9), and ketoconazole (CYP3A4) on fluoxetine N-demethylation in pooled human liver microsomes. Together, these findings suggest a significant role for the polymorphically expressed CYP2D6 in fluoxetine clearance and are consistent with reports on the clinical pharmacokinetics of fluoxetine.

Pentostatin (Nipent): a review of potential toxicity and its management.

Pentostatin (Nipent; SuperGen, San Ramon, CA) is a safe and well-tolerated medication but, like all chemotherapeutic agents, it may be associated with some toxicity. The toxicity seen with pentostatin is dose and schedule dependent and can be minimized by appropriate dosing. The dose of pentostatin should never exceed 4 mg/m2. A dose reduction is required for patients with renal insufficiency. Renal and neurological toxicities may occur, yet are uncommon with appropriate dosing. Nausea and vomiting also occur; however, they are usually controlled with antiemetic therapy. Like the other purine nucleoside analogs, pentostatin is an immunosuppressive drug that may increase the risk of infection, especially with opportunistic organisms. Prophylactic antibiotics should be considered when treating patients with pentostatin.

An old drug for a new disease: pentostatin (Nipent) in acute graft-versus-host disease.

Bone marrow transplantation has become the modality of choice for a number of malignant conditions. One of the primary causes of morbidity and mortality following bone marrow transplantation is graft-versus-host disease (GVHD). Moderate to severe acute GVHD affects 9% to 35% of patients undergoing standard allogeneic bone marrow transplantation. The incidence of chronic GVHD is approximately 40% to 50%. In our experience at Johns Hopkins Oncology Center, patients with stages 2, 3, and 4 acute GVHD had median survivals of only 5.4, 3.6, and 2.5 months, respectively, despite treatment. Patients with chronic GVHD do not fare much better. Their overall 10-year mortality rate remains high at 42%. Significant failure rates and toxicities have been associated with all available therapeutic options for GVHD. Pentostatin (Nipent; SuperGen, San Ramon, CA) is currently used to treat a variety of hematologic malignancies. In addition to its antineoplastic effects, considerable immunosuppressive properties have been reported. Pentostatin affects the immune system by decreasing lymphocyte number and function. Its immunosuppressive effect has promise for the treatment of GVHD and warrants further study.

Neuromuscular effects of rapacuronium in pediatric patients during nitrous oxide-halothane anesthesia: comparison with mivacurium.

PURPOSE: To describe neuromuscular effects of rapacuronium in pediatric patients during N2O-halothane anesthesia and compare them with mivacurium in children. METHODS: 103 pediatric patients, seven days -12 yr, received rapacuronium or mivacurium during N2O-halothane anesthesia. Onset and recovery of block were measured using EMG (Datex). Block was compared between groups based on drug treatment and age. Children < two years received 1 or 2 mg x kg(-1) rapacuronium: 2-12 yr received either 2 mg x kg(-1) or 3 mg x kg(-1) rapacuronium, or 0.2 mg x kg(-1) mivacurium. RESULTS: There were no differences in onset (1.7+/-1.8 min) or maximum block (T1 2.4+/-8%) among neonates, infants, and toddlers after either dose of rapacuronium. There was no difference between 1 and 2 mg x kg(-1) of rapacuronium block at 60 sec. Train-of-four ratio (T4/T1) >0.7 occurred later after 2 mg x kg(-1) than 1 mg x kg(-1) in these patients (P<0.05). There was no difference in T25 among neonates, infants and toddlers for 1 mg x kg(-1) or 2 mg x kg(-1) doses. Rapacuronium, 3 mg x kg(-1), produced maximum block 1.5 min earlier than did mivacurium, 0.2 mg x kg(-1) (P<0.001). There was no difference in block at 60 sec, maximum block or time to maximum block between 2 and 3 mg x kg(-1) rapacuronium for children > two years of age. Maximum block occurred 1.0+/-0.5 min after 2 or 3 mg x kg(-1) when T1 was 0.2+/-1.1% of baseline. T25 and T4/T1 >0.7 occurred 10 to 11 min later after this dose of rapacuronium than after mivacurium. CONCLUSION: Rapacuronium produces block earlier than mivacurium. Recovery from rapacuronium block is dose related and slower than that following mivacurium during halothane anesthesia.