Imaging considerations for in vivo 13C metabolic mapping using hyperpolarized 13C-pyruvate

One of the challenges of optimizing signal-to-noise ratio (SNR) and image quality in (13)C metabolic imaging using hyperpolarized (13)C-pyruvate is associated with the different MR signal time-courses for pyruvate and its metabolic products, lactate and alanine. The impact of the acquisition time window, variation of flip angles, and order of phase encoding on SNR and image quality were evaluated in mathematical simulations and rat experiments, based on multishot fast chemical shift imaging (CSI) and three-dimensional echo-planar spectroscopic imaging (3DEPSI) sequences. The image timing was set to coincide with the peak production of lactate. The strategy of combining variable flip angles and centric phase encoding (cPE) improved image quality while retaining good SNR. In addition, two aspects of EPSI sampling strategies were explored: waveform design (flyback vs. symmetric EPSI) and spectral bandwidth (BW = 500 Hz vs. 267 Hz). Both symmetric EPSI and reduced BW trended toward increased SNR. The imaging strategies reported here can serve as guidance to other multishot spectroscopic imaging protocols for (13)C metabolic imaging applications.

Phase I study of pemetrexed (P) and pegylated liposomal doxorubicin (PLD) in patients with refractory breast, ovarian, primary peritoneal, or fallopian tube cancer

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Background: P and PLD are clinically active as single agents and synergistic in preclinical models. This phase I, open-label trial determined the maximum tolerated dose (MTD) and safety profile of P followed by PLD in patients (pts) with breast or gynecologic cancers. Methods: Using standard phase I (3+3 dose escalation) study design, cohorts of 3–9 pts received escalating doses of P followed by PLD in 28-day cycles: P 400–500 mg/m2 on Days 1 and 15 and PLD 30–45 mg/m2 on Day 1. All pts received folic acid (350–1000 μg daily) and vitamin B12 (1000 μg) until 21 days after last dose of P. Pts continued until dose-limiting toxicity (DLT) or disease progression (PD) occurred. Results: From 11/05 to 1/08, 29 pts were registered/treated. Median age: 60.6 years (range, 47.5–80.1); ECOG performance status 0/1: 28%/72%; primary disease sites: ovarian (55%), breast (35%), peritoneal (10%); prior therapies: chemotherapy (100%), surgery (72%), hormones/biologics (35%), radiation (21%). Dosing results are shown below. At dose level (L) 2 and L3, 1 pt/cohort had DLTs; L5 was added and 3/3 pts had DLTs; 4 more pts were treated at L4 (1 pt replaced). Most frequent drug-related Grade 3–4 hematologic toxicities: neutropenia (86%), leukopenia (59%), thrombocytopenia (48%), anemia (41%). Most frequent drug-related Grade 3–4 nonhematologic toxicities: hand-foot syndrome (14%), hypokalaemia (10%). Major reasons for discontinuation: PD (48%), toxicity (28%), pt request (14%). Overall best responses (n=24): 5 pts (21%) had partial response (PR), 14 pts (58%) had stable disease (SD), 2 pts (8%) had PD, 3 pts (13%) were not evaluable. All 5 PR and 8 SD pts were ovarian; 5 SD and both PD pts were breast. Conclusions: P followed by PLD was reasonably tolerated in this heavily-pretreated population. The MTD was P 500 mg/m2 and PLD 40 mg/m2. These dose levels may be carried forward to phase II studies in more specific patient populations.

[Table: see text]

[Table: see text]

Preliminary results of a randomized phase II study of paclitaxel and bevacizumab ± gemcitabine as first-line treatment for metastatic breast cancer

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Background: The addition of bevacizumab (B) to paclitaxel (P) results in a significant improvement in PFS in pts with metastatic breast cancer (MBC) (Miller K, et al. New Engl J Med 2007). A randomized Phase II trial examining the efficacy and safety of adding gemcitabine (G) to the PB doublet has completed enrollment. Reported here are preliminary efficacy and safety results. Methods: This is a US, multicenter, randomized, superiority trial. Eligible pts have locally advanced or metastatic breast cancer, ECOG PS 0 or 1, and no prior cytotoxic therapy for metastatic disease. Prior adjuvant or neoadjuvant treatment with a taxane or endocrine therapy is allowed. Pts are randomized to receive P 90 mg/m2 on Days 1, 8, and 15, followed by B 10 mg/kg on Days 1 and 15 of a 28-day cycle, or the same regimen plus G 1,500 mg/m2 on Days 1 and 15. Primary endpoint is response rate according to RECIST criteria. Results: Between May 2006 and February 2008, 189 women were randomized to treatment. The table below summarizes currently available results. Grades 1–2 alopecia occurred in 28% of pts in the PB arm and in 38% of pts in the PB+G arm. One pt (2%) in the PB arm experienced a Grade 3 nosebleed. Grades 3 and 4 thrombotic events occurred respectively in 0% and 2% of pts in the PB arm, and in 3% and 2% of pts in the PB+G arm. Four pts (7%) in the PB arm and 3 pts (5%) in the PB+G arm discontinued due to treatment-related AEs. Three on-study deaths have occurred, none deemed related to study treatment. Conclusions: Study follow-up is ongoing. Full results will be available at the time of the meeting. Therapy with PB ± G is feasible and does not appear to be associated with significant bleeding or thrombotic events. As expected, the addition of G to the PB doublet appears to increase the incidence of neutropenia in pts with MBC.

[Table: see text]

[Table: see text]

Multiplexed immunobead-based assay for detection of oral cancer protein biomarkers in saliva

OBJECTIVE

For clinical applications of biomarkers, there is a need for multiplex assays using high throughput platforms. The objective of this study was to determine the efficacy of Luminex Multianalyte Profiling (xMAP) technology for measurement of salivary proteins and to evaluate whether multiplex assays are as effective as single-plex assays and enzyme-linked immunosorbent assay (ELISA).

RESULTS

The average levels of interleukin-8 (IL-8) from the single-plex assay were 3313.2 +/- 3759.8 pg ml(-1) [oral squamous cell carcinoma (OSCC), n = 20] and 1061.7 +/- 1978.8 pg ml(-1) (control, n = 20). The IL-1beta average levels from the single-plex assay were 945.2 +/- 1134.8 pg ml(-1) (OSCC, n = 20) and 314.2 +/- 444.8 pg ml(-1) (control, n = 20). The average levels of IL-8 from the multiplex assay were 2834.9 +/- 3385.6 pg ml(-1) (OSCC, n = 20) and 947.3 +/- 2036.8 pg ml(-1) (control, n = 20). The IL-1beta average levels from the multiplex assay were 1013.5 +/- 1221.1 pg ml(-1) (OSCC, n = 20) and 376.3 +/- 576.3 pg ml(-1) (control, n = 20). The correlation coefficient between Luminex and ELISA assay for IL-8 (n = 19) and IL-1beta (n = 19) was 0.91 and 0.84, respectively.

CONCLUSION

Luminex xMAP single-plex and multiplex assays are as effective as ELISA assays for quantification of proteins in saliva. Both IL-8 and IL-1beta were expressed at significantly higher levels in OSCC subjects than in the matched healthy control subjects.

Monophyletic origin of domestic bactrian camel (Camelus bactrianus) and its evolutionary relationship with the extant wild camel (Camelus bactrianus ferus)

The evolutionary relationship between the domestic bactrian camel and the extant wild two-humped camel and the factual origin of the domestic bactrian camel remain elusive. We determined the sequence of mitochondrial cytb gene from 21 camel samples, including 18 domestic camels (three Camelus bactrianus xinjiang, three Camelus bactrianus sunite, three Camelus bactrianus alashan, three Camelus bactrianus red, three Camelus bactrianus brown and three Camelus bactrianus normal) and three wild camels (Camelus bactrianus ferus). Our phylogenetic analyses revealed that the extant wild two-humped camel may not share a common ancestor with the domestic bactrian camel and they are not the same subspecies at least in their maternal origins. Molecular clock analysis based on complete mitochondrial genome sequences indicated that the sub-speciation of the two lineages had begun in the early Pleistocene, about 0.7 million years ago. According to the archaeological dating of the earliest known two-humped camel domestication (5000-6000 years ago), we could conclude that the extant wild camel is a separate lineage but not the direct progenitor of the domestic bactrian camel. Further phylogenetic analysis suggested that the bactrian camel appeared monophyletic in evolutionary origin and that the domestic bactrian camel could originate from a single wild population. The data presented here show how conservation strategies should be implemented to protect the critically endangered wild camel, as it is the last extant form of the wild tribe Camelina.

SNP deserts of Asian cultivated rice: genomic regions under domestication

When performing a genome-wide comparison between indica (93-11) and japonica (Nipponbare), we find 8% of the genome, which have an extremely low SNP rate (< 1 SNP/kb). Inside these 'SNP deserts', experimentally confirmed genes show increased K(a)/K(s) that indicate adaptive selection. To further elucidate this connection, we survey the level and pattern of genetic variation in both cultivated and wild rice groups, using 155 noncoding regions located within SNP deserts. The results suggest that cultivated rice has greatly reduced genetic variation within SNP deserts as compared to either the nondesert or corresponding genomic regions in wild rice. Consistent with this reduction in genetic variation, we find a biased distribution of derived allele frequency in the cultivated group, indicative of positive selection. Furthermore, over half of the confirmed, domestication-related genes are found within SNP deserts, also suggesting that SNP deserts are strongly related to domestication, and might be the key sites in the process of domestication.

The epidemiology and surgical outcomes of patients undergoing primary total hip replacement: an Asian perspective

INTRODUCTION

The number of total knee replacements far exceeds the number of primary total hip replacements (THR) in Singapore. There is a paucity of data regarding patients who undergo THR in Singapore. This paper aimed to study the epidemiology and early postoperative outcomes of patients receiving primary THR in a single tertiary institution.

METHODS

This is a retrospective study of all patients undergoing primary THR between January 2003 and December 2005. The following variables were analysed: patient demographics, surgical approach, mode of implant fixation, postoperative complications and functional outcomes using D'Aubigne and Postel scoring.

RESULTS

There were a total of 115 patients who underwent primary THR over a 36-month period. The mean age of patients was 55 (range 23-80) years. The male-to-female ratio was 1:2. The most common diagnoses in descending order were as follows: inflammatory arthritis, osteoarthritis, avascular necrosis, hip dysplasia and post-traumatic osteoarthritis. Patients were evaluated at a mean follow-up of 41 months, with 90.8 percent having excellent and good outcomes. There were no statistical differences between the surgical approach and implant fixation with regard to postoperative outcome.

CONCLUSION

In Asian patients, the three commonest aetiologies for degenerative hip arthritis were inflammatory arthropathies, primary osteoarthritis and avascular necrosis. Regardless of diagnosis, the patient groups had comparable functional outcomes following THR.

Interleukin-1beta release in the supraoptic nucleus area during osmotic stimulation requires neural function

Interleukin (IL)-1beta is present throughout the magnocellular neuroendocrine system and co-depletes with oxytocin and vasopressin from the neural lobe during salt-loading. To examine whether IL-1beta is released from the dendrites/soma of magnocellular neurones during osmotic stimulation, microdialysis adjacent to the supraoptic nucleus (SON) in conscious rats was combined with immunocapillary electrophoresis and laser-induced fluorescence detection to quantify cytokine in 5-min dialysates collected before (0-180 min; basal), and after (180-240 min), hypertonic saline injected s.c. (1.5 m NaCl). Osmotic release of IL-1beta was compared after inhibiting local voltage-gated channels for Na+ (tetrodotoxin) and Ca2+ (cadmium and nickel) or by reducing intracellular Ca2+ stores (thapsigargin). Immunohistochemistry combined with microdialysis was used to localise cytokine sources (IL-1beta+) and microglia (OX-42+). Under conditions of microdialysis, the basal release of IL-1beta+ in the SON area was measurable and stable (pg/ml; mean +/- SEM) from 0-60 min (2.2 +/- 0.06), 60-120 min (2.32 +/- 0.05) and 120-180 min (2.33 +/- 0.06), likely originating locally from activated microglia (OX42+; IL-1beta+; ameboid, hypertrophied) and magnocellular neurones expressing IL-1beta. In response to osmotic stimulation, IL-1beta increased progressively in dialysates of the SON area by a mechanism dependent on intracellular Ca2+ stores sensitive to thapsigargin and, similar to dendritic secretion of oxytocin and vasopressin, required local voltage-gated Na+ and Ca2+ channels for activation by osmoregulatory pathways from the forebrain. During osmotic stimulation, neurally dependent release of IL-1beta in the SON area likely upregulates osmosensitive cation currents on magnocellular neurones (observed in vitro by others), to facilitate dendritic release of neurohypophysial hormones.

Prosaposin is an AR-target gene and its neurotrophic domain upregulates AR expression and activity in prostate stromal cells

Recent studies have introduced prosaposin (PSAP) as a pleiotrophic growth factor for prostate cancer (PCa). We have previously reported that PSAP or one of its known active molecular derivatives, saposin C functions as an androgen-agonist and androgen-regulated gene (ARG) for androgen-sensitive (AS) PCa cell lines. Due to the potential significance of androgen receptor (AR)-expressing stroma in PCa, we evaluated a possible bi-directional paracrine regulatory interactions between DHT and PSAP in AR-positive prostate stromal (PrSt) cells. We report that saposin C in a ligand-independent manner increased AR expression, its nuclear content, and tyrosine phosphorylation. DHT treatment of PrSt cells increased PSAP expression. We also demonstrated both serum- and androgen-inducibility of a previously characterized hormone-responsive element (HRE) located in the proximal region of PSAP promoter. In addition, conditioned-media derived from PrSt cells and bone fibroblasts (i.e., MSF) differentially increased PSAP-promoter activity in androgen-independent (AI) PC-3 and AS LNCaP cells. Our data for the first time demonstrate that not only saposin C or PSAP regulates AR expression/activity, but also function as an ARG in PrSt. Ligand-independent activation of AR by PSAP or saposin C in PCa and stromal cells may contribute not only to prostate carcinogenesis at an early stage, but also in AI progression of the disease in an androgen-deprived tumor microenvironment.

Association of polymorphisms of the <i>GHRHR</i> gene with growth traits in cattle (Brief report)

Abstract. The hypothalamic hormone, growth hormone-releasing hormone (GHRH), is the principal stimulator of pituitary growth hormone (GH) synthesis and secretion. Its pituitary receptor is well characterized as a member of the superfamily of G protein-coupled receptors (MAYO et al., 1992). GHRH and its receptor provide important functions in the regulation of the GH axis and in the development and proliferation of pituitary somatotropes (LIN-SU et al., 2002). By now, polymorphisms of bovine GHRHR were not reported. In the present experiment the 5' flanking region, the coding region and partially introns of GHRHR were screened to detect the SNPs in the predominant cattle breeds of China.

PCR-SSCP and &lt;i&gt;Hin6&lt;/i&gt;I PCR-RFLP detecting novel anonymous SNPs within ovine &lt;i&gt;PROP1&lt;/i&gt; gene (Brief report)

Abstract. PROP1 plays a direct or indirect key role in the ontogenesis of pituitary gonadotropes, as well as somatotropes, lactotropes and caudomedial thyrotropes (WU et al., 1998). Mutations of PROP1 are responsible for deficiencies of POU1F1, GH, prolactin (PRL) and thyroid stimulating hormone (TSH) in Snell and Jackson dwarf mice and in man, as well as deficiencies of LH and FSH, suggesting that the PROP1 gene is a potential candidate gene associating with production traits in animal breeding and genetics. To date, no polymorphism of PROP1 gene has been reported in ruminant animals except bovine (PAN et al., 2007). So, the objective of this study is to investigate the polymorphism of all coding regions within ovine PROP1 gene by PCR-SSCP, DNA sequencing and PCR-RFLP methods, which will possibly contribute to conducting association analysis and evaluating them as genetic markers in animal breeding and genetics.

Clinicopathological features and prognosis of drug rash with eosinophilia and systemic symptoms: a study of 30 cases in Taiwan

BACKGROUND

Drug rash with eosinophilia and systemic symptoms (DRESS), a group of non-blistering severe cutaneous adverse drug reactions (SCADRs), is characterized by skin rash and multiorgan involvement. Details of this reaction have not been reported in the literature so far.

AIM

We investigate clinical and pathological features and prognosis of DRESS and hope this study will provide data concerning this disorder in Taiwan.

METHODS

From January 2001 to June 2006, a total of 30 patients, diagnosed with DRESS, were enrolled and evaluated for demographic characteristics, pathological findings, complications and outcome.

RESULTS

Patient ages ranged from 13 to 78, with an equal sex ratio. The most common offending drug was allopurinol followed by carbamazepine. Pathologic changes observed were lichenoid dermatitis, erythema multiforme, pseudolymphoma and vasculitis. Impairment of liver and renal functions and blood dyscrasia were frequent complications. Active infection or reactivation of HHV-6 was observed in 7 of 11 patients studied serologically. Two patients developed type 1 diabetes mellitus. The mortality rate was 10% (3 of 30).

CONCLUSIONS

DRESS is a heterogeneous group of life-threatening conditions. The leading drug in DRESS in Taiwan is allopurinol. High eosinophil count and multiple underlying diseases are poor prognostic factors in patients with DRESS.

Microtia: ear reconstruction using tissue expander and autogenous costal cartilage

Ear reconstruction is one of the most challenging surgeries faced by the reconstructive surgeon. Currently, the use of autogenous costal cartilage is still best practice for microtia reconstruction. However, the relative deficiency of thin skin for coverage of the cartilage framework remains a limiting factor. Since 1994, we have used tissue expander in the mastoid area and innovated a technique to fabricate cartilage framework. All these innovations may solve the deficiency of the skin and improve cartilaginous framework definition. In conclusion, tissue expander offers a non-hairbearing, thin, well-vascularised skin to envelope an erect, contour-accentuated framework. Most patients with microtia are satisfied with their ear reconstruction.