Dendritic cells in autologous hematopoietic stem cell transplantation for diffuse large B-cell lymphoma: graft content and post transplant recovery predict survival

Allograft dendritic cell (DC) content has been identified as a predictor of relapse and event-free survival after allogeneic bone marrow transplantation. However, the prognostic importance of DCs has not been evaluated in the setting of autologous hematopoietic stem cell transplantation (HSCT). We prospectively determined pre-transplant and post transplant DC levels, including DC1 and DC2 subset levels, in 53 patients with diffuse large B-cell non-Hodgkin's lymphoma (DLBC NHL) undergoing autologous HSCT. Pre-transplant DCs were measured in the collected stem cell products and were therefore indicative of cell numbers infused directly into patients; post transplant analysis of DCs was performed on the peripheral blood of patients 6 weeks after the infusion of autologous stem cells. Higher pre-transplant levels of DC1 cells and total DCs were significantly associated with improved survival. Similarly, greater post transplant levels of total DCs and both subsets were significantly associated with survival. These findings suggest a relationship between DC reconstitution and survival following autologous HSCT for DLBC NHL. Strategies to increase autograft DC content or accelerate DC recovery after autologous HSCT might improve outcomes in this setting.

Mapping the fluorescence decay lifetime of a conjugated polymer in a phase-separated blend using a scanning near-field optical microscope

We have studied a blend of the polymers poly(9,9-dioctylfluorene) (F8) dispersed in an inert matrix of polystyrene (PS) using time-resolved scanning near-field optical microscopy (SNOM). On spin-casting, phase separation occurs between the two polymers resulting in a thin film characterized by an F8-rich phase and a PS-rich phase. By spatially mapping the intensity of photoluminescence from the film, we find that there is a low concentration of F8 trapped within the PS-rich phase. We find that the fluorescence emission lifetime (measured at 440 nm) of F8 trapped within the PS-rich phase is significantly longer than that from the F8-rich phase (290 ps compared to 235 ps). Furthermore, spectral measurements indicate that the F8 emission from the PS-rich phase is characterized by a reduced fraction of emission from fluorenone defect states. Taken together, our measurements suggest that in the PS-rich phase interchain exciton diffusion between F8 molecules is suppressed significantly by the effect of dilution.

Sorghum expressed sequence tags identify signature genes for drought, pathogenesis, and skotomorphogenesis from a milestone set of 16,801 unique transcripts

Improved knowledge of the sorghum transcriptome will enhance basic understanding of how plants respond to stresses and serve as a source of genes of value to agriculture. Toward this goal, Sorghum bicolor L. Moench cDNA libraries were prepared from light- and dark-grown seedlings, drought-stressed plants, Colletotrichum-infected seedlings and plants, ovaries, embryos, and immature panicles. Other libraries were prepared with meristems from Sorghum propinquum (Kunth) Hitchc. that had been photoperiodically induced to flower, and with rhizomes from S. propinquum and johnsongrass (Sorghum halepense L. Pers.). A total of 117,682 expressed sequence tags (ESTs) were obtained representing both 3' and 5' sequences from about half that number of cDNA clones. A total of 16,801 unique transcripts, representing tentative UniScripts (TUs), were identified from 55,783 3' ESTs. Of these TUs, 9,032 are represented by two or more ESTs. Collectively, these libraries were predicted to contain a total of approximately 31,000 TUs. Individual libraries, however, were predicted to contain no more than about 6,000 to 9,000, with the exception of light-grown seedlings, which yielded an estimate of close to 13,000. In addition, each library exhibits about the same level of complexity with respect to both the number of TUs preferentially expressed in that library and the frequency with which two or more ESTs is found in only that library. These results indicate that the sorghum genome is expressed in highly selective fashion in the individual organs and in response to the environmental conditions surveyed here. Close to 2,000 differentially expressed TUs were identified among the cDNA libraries examined, of which 775 were differentially expressed at a confidence level of 98%. From these 775 TUs, signature genes were identified defining drought, Colletotrichum infection, skotomorphogenesis (etiolation), ovary, immature panicle, and embryo.

Fungal biology reaps the benefit of genomics

A report on the 23rd Fungal Genetics Conference, Pacific Grove, USA, 15-20 March 2005.

A report on the 23rd Fungal Genetics Conference, Pacific Grove, USA, 15-20 March 2005.

Gene discovery and gene expression in the rice blast fungus, Magnaporthe grisea: analysis of expressed sequence tags

Over 28,000 expressed sequence tags (ESTs) were produced from cDNA libraries representing a variety of growth conditions and cell types. Several Magnaporthe grisea strains were used to produce the libraries, including a nonpathogenic strain bearing a mutation in the PMK1 mitogen-activated protein kinase. Approximately 23,000 of the ESTs could be clustered into 3,050 contigs, leaving 5,127 singleton sequences. The estimate of 8,177 unique sequences indicates that over half of the genes of the fungus are represented in the ESTs. Analysis of EST frequency reveals growth and cell type-specific patterns of gene expression. This analysis establishes criteria for identification of fungal genes involved in pathogenesis. A large fraction of the genes represented by ESTs have no known function or described homologs. Manual annotation of the most abundant cDNAs with no known homologs allowed us to identify a family of metallothionein proteins present in M. grisea, Neurospora crassa, and Fusarium graminearum. In addition, multiply represented ESTs permitted the identification of alternatively spliced mRNA species. Alternative splicing was rare, and in most cases, the alternate mRNA forms were unspliced, although alternative 5' splice sites were also observed.

Simple sequence repeat marker diversity in cassava landraces: genetic diversity and differentiation in an asexually propagated crop

Cassava (Manihot esculenta) is an allogamous, vegetatively propagated, Neotropical crop that is also widely grown in tropical Africa and Southeast Asia. To elucidate genetic diversity and differentiation in the crop's primary and secondary centers of diversity, and the forces shaping them, SSR marker variation was assessed at 67 loci in 283 accessions of cassava landraces from Africa (Tanzania and Nigeria) and the Neotropics (Brazil, Colombia, Peru, Venezuela, Guatemala, Mexico and Argentina). Average gene diversity (i.e., genetic diversity) was high in all countries, with an average heterozygosity of 0.5358 +/- 0.1184. Although the highest was found in Brazilian and Colombian accessions, genetic diversity in Neotropical and African materials is comparable. Despite the low level of differentiation [F(st)(theta) = 0.091 +/- 0.005] found among country samples, sufficient genetic distance (1-proportion of shared alleles) existed between individual genotypes to separate African from Neotropical accessions and to reveal a more pronounced substructure in the African landraces. Forces shaping differences in allele frequency at SSR loci and possibly counterbalancing successive founder effects involve probably spontaneous recombination, as assessed by parent-offspring relationships, and farmer-selection for adaptation.

Transcriptional regulation of biomass-degrading enzymes in the filamentous fungus Trichoderma reesei

The filamentous fungus Trichoderma reesei produces and secretes profuse quantities of enzymes that act synergistically to degrade cellulase and related biomass components. We partially sequenced over 5100 random T. reesei cDNA clones. Among the sequences whose predicted gene products had significant similarity to known proteins, 12 were identified that encode previously unknown enzymes that likely function in biomass degradation. Microarrays were used to query the expression levels of each of the sequences under different conditions known to induce cellulolytic enzyme synthesis. Most of the genes encoding known and putative biomass-degrading enzymes were transcriptionally co-regulated. Moreover, despite the fact that several of these enzymes are not thought to degrade cellulase directly, they were coordinately overexpressed in a cellulase overproducing strain. A variety of additional sequences whose function could not be ascribed using the limited sequence available displayed analogous behavior and may also play a role in biomass degradation or in the synthesis of biomass-degrading enzymes. Sequences exhibiting additional regulatory patterns were observed that might reflect roles in regulation of cellulase biosynthesis. However, genes whose products are involved in protein processing and secretion were not highly regulated during cellulase induction.

A draft sequence of the rice genome (Oryza sativa L. ssp. japonica)

The genome of the japonica subspecies of rice, an important cereal and model monocot, was sequenced and assembled by whole-genome shotgun sequencing. The assembled sequence covers 93% of the 420-megabase genome. Gene predictions on the assembled sequence suggest that the genome contains 32,000 to 50,000 genes. Homologs of 98% of the known maize, wheat, and barley proteins are found in rice. Synteny and gene homology between rice and the other cereal genomes are extensive, whereas synteny with Arabidopsis is limited. Assignment of candidate rice orthologs to Arabidopsis genes is possible in many cases. The rice genome sequence provides a foundation for the improvement of cereals, our most important crops.

A draft sequence of the rice genome (Oryza sativa L. ssp. japonica)

The genome of the japonica subspecies of rice, an important cereal and model monocot, was sequenced and assembled by whole-genome shotgun sequencing. The assembled sequence covers 93% of the 420-megabase genome. Gene predictions on the assembled sequence suggest that the genome contains 32,000 to 50,000 genes. Homologs of 98% of the known maize, wheat, and barley proteins are found in rice. Synteny and gene homology between rice and the other cereal genomes are extensive, whereas synteny with Arabidopsis is limited. Assignment of candidate rice orthologs to Arabidopsis genes is possible in many cases. The rice genome sequence provides a foundation for the improvement of cereals, our most important crops.

Effect of incision and saphenous vein grafting for Peyronie's disease on penile length and sexual satisfaction

PURPOSE

We determined the effect of incision and saphenous vein grafting on penile length, erectile function and overall sexual satisfaction in men with Peyronie's disease.

MATERIALS AND METHODS

A total of 24 consecutive men underwent plaque incision and saphenous vein grafting with postoperative daily use of a vacuum erection device. Erect penile length, pain, curvature and erectile function were assessed before and after surgery, and overall sexual satisfaction was scored from 1 to 5 by a validated instrument.

RESULTS

Of the 22 patients in whom adequate followup data were available mean penile length was increased 2.1 cm. as a result of surgery (p <0.001). Median score of overall satisfaction with sex life was 4 or moderately satisfied. Of the 86% of men who achieved sexual intercourse after surgery 54% used no erectile aids and 32% required sildenafil or intracavernous injection. Complete erectile dysfunction was present in 14% of cases. Patients who reported erectile difficulty preoperatively were significantly more likely to have erectile dysfunction postoperatively that required erectile aids. Arterial insufficiency on duplex Doppler ultrasound was associated with a higher likelihood of complete erectile dysfunction. Complications in 33% of patients included complete erectile dysfunction in 3 and significant persistent penile curvature in 1.

CONCLUSIONS

Incision and venous grafting of plaque leads to statistically and clinically significant increases in penile length in men with Peyronie's disease. Preoperative erectile dysfunction and cavernous arterial insufficiency were associated with a higher risk of postoperative erectile dysfunction. Nevertheless, patients reported a high degree of satisfaction with their overall sex life.

Inhibition of Kupffer cells reduced CXC chemokine production and liver injury

BACKGROUND

Cytokine production is a critical component of ischemia/reperfusion (IR) injury. In the liver, Kupffer cells produce cytokines and chemokines (i.e., cytokines with chemoattractant properties) that are important mediators in neutrophil recruitment and subsequent hepatocellular injury. Therefore, the role of Kupffer cells in chemokine production in hepatic IR injury was investigated.

METHODS

Adult male C57BL/6 mice underwent 90 min of partial hepatic ischemia followed by various reperfusion times (i.e., 0, 1.5, 3, and 6 h). Gadolinium chloride (GC), which inhibits Kupffer cell activity, was administered to mice 48 and 24 h prior to ischemia. The control group received a corresponding volume of normal saline. Plasma levels of the cytokine macrophage inflammatory protein-2 (MIP-2), KC, and tumor necrosis factor (TNF)-alpha and liver mRNA were measured. Liver injury was assessed by plasma level of alanine transaminase (ALT) and histopathology.

RESULTS

A reperfusion time-dependent liver injury occurred as indicated by increased levels of plasma ALT and histopathology. The injury was associated with increased plasma TNF-alpha, MIP-2, and KC and their hepatic mRNA expression and neutrophil infiltration into ischemic lobes of the liver. GC treatment significantly reduced the number of Kupffer cells as determined by the immunostained liver tissue sections. The extent of liver injury significantly decreased in GC-treated mice that were associated with decreased levels of plasma ALT, TNF-alpha, MIP-2, and KC and neutrophil infiltration.

CONCLUSIONS

This study suggests that Kupffer cells are major contributors to cytokine production in hepatic IR and their modulation may serve as a potential target for therapeutic intervention.

TBI or not TBI: that is the question. Is it better to measure toe pressure than ankle pressure in diabetic patients?

AIMS

Measurement of ankle blood pressure is a simple method of assessing lower limb arterial blood supply. However, its use in diabetes has been questioned due to the presence of medial artery calcification. Measurement of toe blood pressure has been advocated as an alternative but it is technically more difficult. The aim of this study was to obtain information to guide clinicians as to when pressure measurements should be taken at the toe.

METHODS

Ankle brachial index (ABI) and toe brachial index (TBI) were measured by Doppler ultrasound, or photoplethysmography on 174 subjects with diabetes and 53 control subjects. The Bland and Altman method, and the Cohen's method of measuring agreement between two tests were used to compare ABI with TBI.

RESULTS

The mean differences between ABI and TBI in control and diabetic subjects are 0.40 +/- 0.13 and 0.37 +/- 0.15, respectively. Nearly all diabetic patients with an ABI < 1.3 have an ABI-TBI gradient falling within the normal range established from the non-diabetic cohort. In contrast, the majority of diabetic subjects with an ABI > or = 1.3 have ABI-TBI differences outside this range. When patients are categorized according to ABI and TBI, there is also good agreement between the tests when ABI is low or normal (84% and 78% agreement, respectively), but not when ABI is elevated.

CONCLUSION

In the majority of patients with diabetes, assessment of TBI conveys no advantage over ABI in determining perfusion pressure of the lower limbs. Only in those patients with overt calcification, which gives an ABI > or = 1.3, are toe pressure measurements superior. This guideline should simplify assessment and treatment of diabetic patients with disease of the lower limbs. Diabet. Med. 18, 528-532 (2001)

Angiotensin type 2 receptor is expressed in the adult rat kidney and promotes cellular proliferation and apoptosis

BACKGROUND

Angiotensin II (Ang II) is associated with cell proliferation and apoptosis. The role of the angiotensin type 2 receptor (AT2R) in these processes remains controversial. Conventional radioligand binding of 125I-Sar1, Ile8 Ang II in adult kidney has failed to demonstrate the binding for the AT2R.

METHODS

The presence of the AT2R was explored in adult rat kidney by in vitro and in vivo autoradiography using the selective AT2R radioligand 125I-CGP 42112B. The roles of the angiotensin type 1 receptor (AT1R) and the AT2R in mediating cellular proliferation and apoptosis were assessed using selective AT1R or AT2R antagonists in Ang II-infused Sprague-Dawley (SD) rats.

RESULTS

125I-CGP 42112B binding was demonstrated by in vitro and in vivo autoradiography techniques in the glomeruli and proximal tubules of SD rats. This binding could be displaced by Ang II and the AT2R antagonist PD123319 but not by the AT1R antagonist valsartan. Subcutaneous infusion of Ang II for 14 days in eight-week-old SD rats induced proliferation of proximal tubular epithelial cells, as assessed by a twofold increase in proliferating cell nuclear antigen (PCNA)-positive cells and apoptosis, as assessed by a threefold increase in terminal dUTP nick end labeling (TUNEL)-positive cells. The administration of the AT2R antagonist PD123319 or the AT1R antagonist valsartan was associated with attenuation of the increases in both PCNA- and TUNEL-positive cells following Ang II infusion. Ang II infusion was associated with increased osteopontin gene and protein expression, which could be reduced by treatment with either valsartan or PD123319.

CONCLUSION

These findings indicate that there is significant expression of the AT2R in the adult kidney, and that the AT2R has a role in mediating Ang II-induced proliferation and apoptosis in proximal tubular epithelial cells and expression of osteopontin.

Knowledge of Centers for Disease Control and Prevention guidelines for the use of vancomycin at a large tertiary care children's hospital

OBJECTIVE

In 1994, the Centers for Disease Control and Prevention (CDC) published guidelines to encourage prudent use of vancomycin. We sought to determine whether physicians could demonstrate knowledge consistent with the guidelines.

DESIGN

Survey consisting of 18 clinical vignettes based on the CDC guidelines.

PARTICIPANTS

All residents, fellows, and attending physicians involved in pediatric inpatient services.

SETTING

Tertiary care children's hospital providing service to an inner-city population and community referral base.

MAIN OUTCOME MEASURES

Comparison of survey scores and individual responses among respondents.

RESULTS

Survey scores did not vary with level of training or whether the respondent was a pediatrician or non-pediatrician. Average scores of attending physicians, fellows, and residents were 74.1% (SD = 13.1), 77.2% (SD = 11.5), and 73.4% (SD = 10.5), respectively, and did not differ significantly. Questions incorrectly answered by more than 30% of respondents concerned the use of vancomycin as: (1) first-line treatment of Clostridium difficile colitis, (2) a topical solution for wound infection, (3) initial, empiric treatment of patients with fever and neutropenia, (4) peri-operative prophylaxis, (5) a preferred agent over beta-lactam antimicrobial agents.

CONCLUSION

Deficits in knowledge regarding appropriate vancomycin use can be localized to certain clinical settings. This observation lends optimism to the notion that targeted educational intervention may improve the appropriate use of vancomycin.

Reactions of hypochlorous acid with tyrosine and peptidyl-tyrosyl residues give dichlorinated and aldehydic products in addition to 3-chlorotyrosine

The toxicity of hypochlorous acid (HOCl) generated from activated neutrophils has been associated with several pathological processes such as atherosclerosis. Formation of 3-chlorotyrosine (Cl-Tyr) has been used as a marker for assessing the involvement of HOCl in such processes. In this study, we aimed to investigate the formation of Cl-Tyr from reaction of HOCl with tyrosine (both free and peptide-bound) and the fate of Cl-Tyr under such conditions. Tyrosine, N-acetyltyrosine, bovine serum albumin, and human low density lipoproteins were incubated with a range of reagent hypochlorite concentrations for varying periods in 10 mM phosphate buffer (pH 7.4) at 22 degrees C. The reaction products, and several biological samples, were hydrolyzed (in the case of proteins), isolated, and purified by high pressure liquid chromatography and characterized or quantitated by mass spectrometry and NMR. A significant amount of 3,5-dichlorotyrosine (diCl-Tyr) was obtained from the bovine serum albumin, low density lipoprotein, and some biological samples, in addition to Cl-Tyr, indicating that Cl-Tyr competes effectively for HOCl even when tyrosine is present in great excess. Cl-Tyr and diCl-Tyr were also formed from free tyrosine but then reacted further with HOCl. This finding differs from a claim in the literature that Cl-Tyr was not formed in such a system. The further reaction products of Cl-Tyr and diCl-Tyr with HOCl were elucidated as their corresponding mono- and dichlorinated 4-hydroxyphenylacetaldehydes. These results indicate the importance of assessing other products of HOCl action in addition to Cl-Tyr.

Expression profile of an androgen regulated prostate specific homeobox gene NKX3.1 in primary prostate cancer

PURPOSE

NKX3.1, a member of the family of homeobox genes, exhibits prostate tissue specific expression and appears to play a role in mouse prostate development. Rapid induction of NKX3.1 gene expression in response to androgens has also been described. On the basis of the established role of androgens in prostatic growth and differentiation and studies showing an association of aberrant homeobox gene expression with the neoplastic process, we hypothesize that alterations of NKX3.1 gene expression play a role in prostate tumorigenesis.

MATERIALS AND METHODS

NKX3.1 expression was analyzed in matched, microdissected normal and tumor tissues from 52 primary prostate cancer specimens from radical prostatectomy by semiquantitative RT-PCR and in situ hybridization and correlated with the clinicopathologic features. NKX3.1 expression was quantified as differential expression between matched tumor and normal tissues and was grouped as overexpression in tumor tissue, reduced expression in tumor tissue and no change between tumor and normal tissues. Androgen regulation of NKX3.1 expression was also studied in LNCaP cells. Androgen receptor (AR) expression in prostate tumor and normal tissue was correlated with NKX3.1 expression.

RESULTS

Comparison of NKX3.1 expression between normal and tumor tissues revealed overexpression in 31% tumor specimens (16 of 52), decreased expression in 21% tumor specimens (11 of 52) and no change in 48% specimens (25 of 52). When these expression patterns were stratified by organ confined and non-organ-confined tumor, a higher percentage of patients exhibited NKX3.1 overexpression in non-organ confined tumor (40%) versus organ confined tumor (22%). Elevated NKX3.1 expression significantly correlated with tumor volume and serum prostate specific antigen (PSA) level in the NKX3.1 overexpression group (p<0.05). Metastatic prostate cancer cell lines did not exhibit mutations in the protein coding sequence of NKX3.1. Additionally, the NKX3.1 expression correlated with AR expression (p<0.01) in vivo in human prostate tissues. Comparison of PSA and NKX3.1 expression in response to androgen revealed a rapid androgen mediated induction of NKX3.1 expression in LNCaP cells. In situ hybridization analysis of representative specimens confirmed RT-PCR observations.

CONCLUSIONS

These results suggest an association of NKX3.1 with a more aggressive phenotype of carcinoma of the prostate. Correlation of AR expression with NKX3.1 in human prostate tissues underscores the androgen regulation of NKX3.1 in the physiologic context of human prostate tissues.