Interactions between stem cells and their niche in the Drosophila ovary

The Drosophila ovary contains at least three types of active stem cells, namely, germ-line stem cells (GSCs), escort stem cells (ESCs), and follicular stem cells (FSCs), which work together to efficiently assemble egg chambers. Among the three stem cell types, the GSC is among the first shown to be controlled by the niche due to its easy identification and welldefined surrounding cells. We have shown that the niche controls GSC self-renewal, anchorage, aging, and competition, and the GSC also signals back to the niche for its maintenance. The FSC is an attractive model for studying epithelial stem cell regulation and signal integration because we have shown that it resembles mammalian epithelial stem cells and requires multiple signaling pathways for its self-renewal. In this chapter, we have highlighted the findings of our studies on interactions between Drosophila ovarian stem cells and their niches during normal development and aging and on stem cell competition for niche occupancy. We further discuss their implications in general stem cell biology and future directions in this exciting area.

Mucosal insulin vaccination for type 1 diabetes prevention

Mucosal administration of autoantigen, if efficacious, is an attractive therapeutic approach for prevention of type 1 diabetes. It can prevent or delay autoimmune diabetes in animal models, but although shown to be safe has not yet been proven effective in human studies. Efficacy may depend upon the dose and route at which antigen is administered, the stage in type 1 diabetes pathogenesis at which treatment is initiated, and the study cohort that is treated. Here we address these issues and propose a clinical translation possibility for mucosal insulin administration in genetically at risk individuals.

P300 plays a role in p16(INK4a) expression and cell cycle arrest

As a cyclin-dependent kinase inhibitor, p16(INK4a) plays a key role in cell cycle progression and cellular differentiation, and its expression is frequently altered in human cancers through epigenetically mediated transcriptional silencing. In this report, we demonstrate that p300 was able to induce cell cycle arrest, and this process was reversed by p16(INK4a) silencing by RNA interference in HeLa cells. We also show that p300 was involved in activation of p16(INK4a) expression in 293T cells. Specifically, p300 cooperated with Sp1 to stimulate both p16(INK4a) promoter activity and mRNA expression. Co-immunoprecipitation and mammalian two-hybrid assays revealed that p300 and Sp1 formed a complex through interaction between the Q domain of p300 and the N-terminal domain of Sp1. The chromatin immunoprecipitation assays verified that p300 was recruited to p16(INK4a) promoter, and the histone acetyltransferase domain of p300 participated in p16(INK4a) activation through inducing hyperacetylation of histone H4 at p16(INK4a) gene. These data suggest that p300 plays a critical role in transcriptional regulation of p16(INK4a) and in cell cycle arrest.

Phase I trial of huA33 antibody plus 5-fluorouracil (5FU), leucovorin, and oxaliplatin in patients with metastatic colorectal cancer [LUD2003–005]

3022

Background: The selective targeting of tumors with monoclonal antibodies (mAb) has emerged as a new therapeutic approach in cancer therapy with the A33 glycoprotein being a promising target in colorectal cancer. Specific tumor localization and low toxicity of a humanised A33 specific mAb (huA33) has previously been demonstrated in patients with colorectal carcinoma. In the present study, we determined the safety and efficacy of the combination of huA33 and 5FU plus leucovorin and oxaliplatin (FOLFOX-4) in patients with metastatic colorectal cancer. Methods: Patients had to present with metastatic colorectal cancer with an expected survival of at least 4 months and no more than 2 different pre-treatment regimens. Patients were excluded if they had previously received oxaliplatin or huA33 mAb. Eligible patients received huA33 (10 mg/m2) by iv infusion weekly for 12 weeks (cycle 1). On study day 15, standard FOLFOX-4 chemotherapy was administered every 2 weeks for 10 weeks. Responding patients received a second cycle of weekly huA33 (10 mg/m2) and biweekly FOLFOX-4 chemotherapy. Results: A total of 19 patients (11 female, 8 male) with a median age of 60 years entered the study. 5 patients had received prior chemotherapy, 2 radiation therapy and 18 surgery. Toxicities observed were as expected for FOLFOX-4 treatment alone with hematological side effects to be most prominent and included (only G3 and G4) 1 anemia and 10 neutropenias. The addition of huA33 to FOLFOX-4 did not change the pattern of known non-hematological toxicities with a low rate (14%) of huA33 mAb associated allergic reactions. One sudden death occurred at cycle five that was neither therapy nor disease related. Within the 16 patients currently available for response assessment, the overall response rate was 38% with 1 CR, 5 PR and 5 disease stabilizations. Conclusion: The combination of FOLFOX-4 as standard chemotherapy for this cohort of patients in combination with the humanized A33 antibody did not increase toxicities and was well tolerated. The overall response rate of 38% is in the response range published so far for the FOLFOX-4 regimen in this setting and warrants further analysis in a larger cohort of patients.

[Table: see text]

Characterization of moisture-sensitive raw materials with simple spectroscopic techniques

The quality of raw materials used in a synthetic process needs to be properly controlled in order to ensure optimal reaction conversion and desired quality of the resulting product. For air and water sensitive raw materials, quantitative analysis can be a challenging task. Spectroscopic techniques possess advantages of simple operation, fast analysis, low consumable costs and high sample throughput for the analysis of reactive raw materials. Three case studies utilizing spectroscopic analysis for air and water sensitive materials are discussed. First, FT-IR spectroscopy was utilized to determine the amount of residual acetic acid in acetic anhydride key raw material. Acetic anhydride was used in a methylenation reaction where the presence of residual acetic acid could quench a base used in the reaction, leading to incomplete conversion. A simple, one-frequency calibration method was developed to quantify acetic acid in acetic anhydride (2-35wt.%). Next, a novel near infrared reflectance spectroscopy (NIRS) method was used to determine the concentration of diisobutyl aluminum hydride (DIBAL-H) in toluene. DIBAL-H is a highly reactive and moisture-sensitive reagent used as a key raw material for the reduction of an active intermediate. A calibration method based on one-frequency was also developed to determine the concentration of DIBAL-H in toluene (0-1.5mole/L). Finally, a NIRS method based on partial least squares regression (PLS) was developed to quantify p-toluenesulfonic acid in p-toluenesulfonic anhydride, which is not amenable to chromatographic analysis.

Phase II trial of vaccination with full length NY-ESO-1/IMX in patients with advanced malignant melanoma

2571

Background: NY-ESO-1 is an immunogenic “cancer-testis” (CT) antigen, expressed in many cancers including melanoma. Iscomatrix adjuvant (IMX), a saponin-based adjuvant, was formulated with NY-ESO-1 (ESO) protein (ESO/IMX). ESO/IMX was highly immunogenic as defined by ESO specific antibody (Ab), delayed type hypersensitivity (DTH) & T-cell responses in patients (pts) with resected ESO+ve cancer. Disease free survival in vaccine recipients with resected melanoma appeared longer than in controls. A prospective evaluation was subsequently undertaken to determine whether ESO/IMX could mediate antitumor responses in pts with advanced NY ESO-1+ve melanoma. Methods: 27 pts were vaccinated in a trial designed to assess objective clinical responses, safety, & immunogenicity. Vaccination consisted of 100 μg ESO/IMX administered q 4 wk × 3; this cycle was repeated in pts without symptomatic progression unless they required other treatment. Pts were then eligible to continue vaccination q12 weeks so long as they were responding or stable. Results: ESO/IMX was well tolerated. 13 pts progressed when evaluated after the first cycle at week 11. No objective clinical responses were seen. Vaccine-induced antibody titers to NY-ESO-1 were comparable to those seen in the earlier minimal residual disease trial (ranging to > 1: 390,000). DTH & T-cell responses were less marked. This occurred despite many pts with advanced measurable disease having pre-existing spontaneous ESO immunity ( Table ). DTH responses were seen in 11 pts; 5 had pre-existing responses (2 were boosted) and 6 were induced. The DTH responses were lost by week 33. Conclusion: No objective responses were seen. Vaccine-induced immunity appeared to be attenuated in the presence of advanced metastatic disease. Ongoing laboratory studies are investigating the role of regulatory T cells in the suppression of ESO-specific immunity in these pts with a view to adopting strategies to counter regulatory responses e.g. low-dose cyclophosphamide prior to vaccination.

[Table: see text]

[Table: see text]

Identification and characterization of six new alternatively spliced variants of the human mu opioid receptor gene, Oprm

The mu opioid receptor plays an important role in mediating the actions of morphine and morphine-like drugs. Receptor binding and a wide range of pharmacological studies have proposed several mu receptor subtypes, but only one mu opioid receptor (Oprm) gene has been isolated. Like the mouse and rat, the human Oprm gene undergoes alternative splicing. In the present studies, we have identified and characterized six new splice variants from the human Oprm gene using a reverse transcription-polymerase chain reaction strategy, yielding a total of 10 human splice variants of the mu opioid receptor MOR-1. All the variants identified contained exons 1, 2 and 3, but differed from MOR-1 itself and each other by splicing downstream from exon 3, resulting in different amino acid sequences. Northern blot analysis demonstrated expression of the variant mRNAs. Receptor binding assays established that these variants belonged to the mu opioid receptor family with limited differences in mu opioid ligand affinities and selectivity. However, adenylyl cyclase and [35S]GTPgammaS binding assays revealed major differences in both potency and efficacy among these variants. The dissociation between binding affinity, potency and efficacy for the opioids among these variants may provide insights into the wide range of opioid responses among these agents observed clinically and opens new avenues in designing selective drugs based upon their efficacy and potency rather simple binding affinity.

Kinetic analysis and subambient temperature on-line on-column derivatization of an active aldehyde

The chromatographic analysis of aldehydes under typical reversed-phase conditions may be a challenging task due to an equilibrium process leading to the formation of a gem diol species regardless of acidic or basic conditions. Initially, a reversed-phase HPLC gradient elution was developed to determine the amount of a n acetylenic aldehyde in a reaction mixture. Significant fronting was observed under acidic and basic conditions even at -5 degrees C. In order to circumvent this problem, a reversed-phase HPLC gradient method on a C18 column at subambient temperature was developed using diethylamine as a mobile phase additive for on-line on-column derivatization of the aldehyde moiety. The on-line on-column reaction rate for the derivatization of the aldehyde with diethylamine was determined as a function of column temperature. An Arrhenius plot was constructed and the activation energy was calculated. The chromatographic behavior of the derivatized acetylenic aldehyde and products formed in-situ in the chromatographic system were studied at various temperatures ranging from -10 to 60 degrees C. It was found that the reaction products could be controlled by adjusting the column temperature. Different reaction pathways were identified as a function of temperature. The products and the reaction pathways were characterized by NMR, LC-MS and UV spectra.

Perturbations in three medullary nuclei enhance fractionated breathing in awake goats

Our aim was to determine the frequency and characteristics of a fractionated pattern of diaphragm and upper airway muscle activity and airflow during wakefulness and sleep in adult goats. A fractionated breath (FBr) was defined as three or more brief (40-150 ms) interruptions in the diaphragm activity not associated with multiple swallows, eructation, mastication, or movement. During a FBr, the discharge pattern in the diaphragm and upper airway muscles showed complete cycles of inspiration and expiration. Whereas the interval between peak diaphragm activity of the breath preceding the FBr to the first diaphragm peak of the FBr was 15-20% less than the average interval of the preceding five control breaths, the breath-to-breath interval of the five breaths after a FBr did not differ from the control breaths before the FBr event. In normal goats, FBr was evident in only 4 of 18 (22%) awake goats and in only one of these goats during non-rapid eye movement sleep. In 35 goats with implanted microtubules in the medulla, FBr were present in 14 (40%) goats. In these goats with FBr, 78% (11 of 14) had one or more implantations into or near the facial, vestibular, or raphe nuclei. The effect of perturbations in these nuclei is probably nonspecific, because injections into these nuclei with mock cerebrospinal fluid or excitatory amino acid-receptor agonist or antagonist produced both increases and decreases in the frequency of the FBr while not altering their characteristics. Finally, a swallow occurred at the termination or during the first breath after 60% of the FBr. We speculate that the FBr manifest 1) the disruption of a neuronal network, which coordinates breathing and other functions (such as swallowing), utilizing the same anatomic structures, and/or 2) transient changes in synaptic inputs that increase the rate of the normal respiratory rhythm generator or allow an ectopic, anomalous generator to become dominant.

Possible dominant-negative mutation of the SHIP gene in acute myeloid leukemia

The SH2 domain-containing inositol 5'-phosphatase (SHIP) is crucial in hematopoietic development. To evaluate the possible tumor suppressor role of the SHIP gene in myeloid leukemogenesis, we examined primary leukemia cells from 30 acute myeloid leukemia (AML) patients, together with eight myeloid leukemia cell lines. A somatic mutation at codon 684, replacing Val with Glu, was detected in one patient, lying within the signature motif 2, which is the phosphatase active site. The results of an in vitro inositol 5'-phosphatase assay revealed that the mutation reduced catalytic activity of SHIP. Leukemia cells with the mutation showed enhanced Akt phosphorylation following IL-3 stimulation. K562 cells transfected with the mutated SHIP-V684E cDNA showed a growth advantage even at lower serum concentrations and resistance to apoptosis induced by serum deprivation and exposure to etoposide. These results suggest a possible role of the mutated SHIP gene in the development of acute leukemia and chemotherapy resistance through the deregulation of the phosphatidylinositol-3,4,5-triphosphate (PI(3,4,5)P3)/Akt signaling pathway. This is the first report of a mutation in the SHIP gene in any given human cancer, and indicates the need for more attention to be paid to this gene with respect to cancer pathogenesis.

History of Chinese stereotactic and functional neurosurgery

Chinese stereotactic and functional neurosurgery started in 1963. Dr. Jian-Ping Xu did stereotactic surgery for Parkinson's disease with a small Cartesian coordinate stereotactic device which he designed. In 1983, the first Chinese Institute of Stereotactic and Functional Neurosurgery was established by Dr. Jian-Ping Xu and Dr. Ye-Han Wang in the Anhui Provincial Hospital in the city of Hefei. Since then, the Institute has hosted an annual National Workshop on Stereotactic and Functional Neurosurgery, where more than 80% of the functional neurosurgeons now practicing in China have been trained. In 1986, the Chinese Society of Stereotactic and Functional Neurosurgery was established, and the first issue of the Chinese Journal of Stereotactic and Functional Neurosurgery was published. With more than 35 years of development, stereotactic and functional neurosurgery has become a very important branch of surgery in China. More than 5,000 functional neurosurgery procedures and more than 8,000 stereotactic radiosurgery procedures are now performed annually.

Contributions from rostral medullary nuclei to coordination of swallowing and breathing in awake goats

The purpose of this study was to determine whether neurons in the facial (FN), gigantocellularis reticularis (RGN), and vestibular (VN) nuclei contribute to the regulation of breathing, swallowing, and the coordination of these two functions. Microtubules were chronically implanted bilaterally in goats. Two weeks later during wakefulness, 100-nl unilateral injections were made of mock cerebral spinal fluid or an excitatory amino acid receptor agonist or antagonists. When the agonist, N-methyl-D-aspartic acid, was injected into any nuclei, breathing and swallowing increased transiently (15-30%; P < 0.05), whereas only injections of the antagonist 2,3-dihydroxy-6-nitro-7-sulfamoylbenzo-(f)quinoxaline into VN increased swallowing (20%; P < 0.05). The phase of breathing in which the swallows occurred was not altered by any injections. However, more importantly, injections of the agonist and the antagonists significantly altered (P < 0.05) by 5-50% the respiratory phase-dependent timing and tidal volume effect of swallows on breathing relative to mock cerebral spinal fluid injections. In addition, these effects were not uniform for all three nuclei. We conclude that the FN, RGN, and VN are part of a neural circuit in the rostral medulla that regulates and/or modulates breathing, swallowing, and their coordination in the awake state.

Effects of spontaneous swallows on breathing in awake goats

The effects of spontaneous swallows on breathing before, during, and after solitary swallows were investigated in 13 awake goats. Inspiratory (TI) and expiratory (TE) time and respiratory output were determined from inspiratory airflow [tidal volume (VT)] and peak diaphragmatic activity (Dia(peak)). The onset time for 1,128 swallows was determined from pharyngeal muscle electrical activity. During inspiration, the later the swallowing onset, the greater increase in TI and VT, whereas there was no significant effect on TE and Dia(peak). Swallows in early expiration increased the preceding TI and reduced TE, whereas later in expiration swallows increased TE. After expiratory swallows, TI and VT were reduced whereas minimal changes in Dia(peak) were observed. Phase response analysis revealed a within-breath, phase-dependent effect of swallowing on breathing, resulting in a resetting of the respiratory oscillator. However, the shift in timing in the breaths after a swallow was not parallel, further demonstrating a respiratory phase-dependent effect on breathing. We conclude that, in the awake state, within- and multiple-breath effects on respiratory timing and output are induced and/or required in the coordination of breathing and swallowing.

Effects of prostaglandin E2 on gene expression in primary osteoblastic cells from prostaglandin receptor knockout mice

Recent studies have shown that stimulation of osteoclastogenesis in cocultures of osteoblasts and spleen cells in response to prostaglandin E2 (PGE2) is markedly decreased when the osteoblasts are derived from cells lacking either the EP2 or the EP4 receptor. Induction of osteoclast formation requires upregulation of receptor activator of nuclear factor-kappaB ligand (RANKL) on cells of the osteoblastic lineage, which then binds to the RANK receptor on cells of the osteoclast lineage. Osteoprotegerin (OPG) is a decoy receptor for RANKL that can block its interaction with RANK. In addition, macrophage-colony stimulating factor (M-CSF) is essential for osteoclast formation. Finally, PGE2 can increase interleukin-6 (IL-6), which may further enhance osteoclastogenesis. To study the relative influence of the EP2 and EP4 receptors on response of these factors to PGE2, we examined mRNA levels for RANKL, OPG, M-CSF, and IL-6 in primary osteoblastic cell cultures derived from two lines of EP2 knockout mice (EP2-/-) and one line of EP4 knockout mice (EP4-/-) and the relevant wild-type controls (EP2+/+ and EP4+/+). The responses of cells from wild-type animals of all three lines were similar. After PGE2 treatment, RANKL mRNA levels were increased at 2 h, and this was sustained over 72 h. Basal RANKL expression was moderately reduced in EP2-/- cells and markedly reduced in EP4-/- cells. PGE2 increased RANKL mRNA in EP2-/- cells and EP4-/- cells, but the levels were significantly reduced compared with wild-type cells. There were no consistent changes in expression of M-CSF or OPG in the different genotypes or with PGE2 treatment. IL-6 mRNA was variably increased by PGE2 in both wild-type and knockout cells, although the absolute levels were somewhat lower in both EP2-/- and EP4 -/- cultures. Parathyroid hormone (PTH) increased RANKL and IL-6 and decreased OPG mRNA levels similarly in both wild-type and EP2-/- or EP4-/- cells. The major defect in the response to PGE2 in animals lacking either EP2 or EP4 receptors is a reduction in basal and stimulated RANKL levels. Loss of EP4 receptor appears to have a greater effect on basal RANKL expression than EP2.

Gamma Knife radiosurgery as a primary surgical treatment for hypersecreting pituitary adenomas

OBJECT

To estimate the efficacy of Gamma Knife radiosurgery (GKR) especially as a primary surgical treatment for hypersecreting pituitary adenomas.

METHODS

274 patients were treated with GKR. The mean tumor volume was 1.86 cm(3). The mean peripheral dose was 28.7 Gy.

RESULTS

223 patients were followed up for an average of 31.6 months. The dose related to the tumor growth control and endocrinological normalization was detailed and statistical analysis of the data was performed.

CONCLUSION

GKR as a primary surgical treatment for hypersecreting pituitary adenomas may be safe and effective.

Critical roles of a cyclic AMP responsive element and an E-box in regulation of mouse renin gene expression

Mouse As4.1 cells, obtained after transgene-targeted oncogenesis to induce neoplasia in renal renin expressing cells, express high levels of renin mRNA from their endogenous Ren-1(c) gene. We have previously identified a 242-base pair enhancer (coordinates -2866 to -2625 relative to the CAP site) upstream of the mouse Ren-1(c) gene. This enhancer, in combination with the proximal promoter (-117 to +6), activates transcription nearly 2 orders of magnitude in an orientation independent fashion. To further delimit sequences necessary for transcriptional activation, renin promoter-luciferase reporter gene constructs containing selected regions of the Ren-1(c) enhancer were analyzed after transfection into As4.1 cells. These results demonstrate that several regions are required for full enhancer activity. Sequences from -2699 to -2672, which are critical for the enhancer activity, contain a cyclic AMP responsive element (CRE) and an E-box. Electrophoretic mobility shift assays demonstrated that transcription factors CREB/CREM and USF1/USF2 in As4.1 cell nuclear extracts bind to oligonucleotides containing the Ren-1(c) CRE and E-box, respectively. These two elements are capable of synergistically activating transcription from the Ren-1(c) promoter. Moreover, mutation of either the CRE or E-box results in almost complete loss of enhancer activity, suggesting the critical roles these two elements play in regulating mouse Ren-1(c) gene expression. Although the Ren-1(c) gene contains a CRE, its expression is not induced by cAMP in As4.1 cells. This appears to reflect constitutive activation of protein kinase A in As4.1 cells since treatment with the protein kinase A inhibitor, H-89, caused a significant reduction in Ren-1(c) gene expression and this reduction is mediated through the CRE at -2699 to -2688.

The Arabidopsis thaliana ethylene-responsive element binding protein (AtEBP) can function as a dominant suppressor of Bax-induced cell death of yeast

We identified genes based on screening of an Arabidopsis cDNA library for functional suppressors of mouse Bax-induced cell death of yeast cells. Interestingly, the cDNA encoding AtEBP, known as Arabidopsis thaliana ethylene-responsive element binding protein, was isolated numerous times in the functional screen (82% of all suppressors). Full-length AtEBP and its localization to the nucleus were essential for the suppression of Bax-induced cell death. Morphological abnormality of intracellular network that is a hallmark of Bax-induced cell death was attenuated by expression of AtEBP.

Negative pressure effects on mechanically opposing pharyngeal muscles in awake and sleeping goats

Our aim was to investigate the effects of the negative pressure reflex on mechanically opposing pharyngeal muscles during wakefulness, slow-wave sleep (SWS), and rapid eye movement (REM) sleep. In four goats with isolated upper airways, we measured tracheal airflow and electrical activity of the thyropharyngeus (TP; constricting), the stylopharyngeus (SP; dilating), and the diaphragm (Dia). In the wakefulness state in response to negative pressure tests, TP decreased (65%), SP increased (198%), and tidal volume (VT) (66%) and rate of rise of Dia (Dia(slope), 69%) decreased (P < 0.02). Similarly, during SWS, the negative pressure response of TP (31%), VT (61%), and Dia(slope) (60%) decreased, whereas SP (113%) increased, relative to SWS control (P < 0.02). In REM sleep, the negative pressure response by TP and SP were small, whereas both VT (38%) and Dia(slope) (24%) were greatly decreased (P < 0.02) compared with REM control. Inspiratory duration remained unchanged in response to negative pressure tests in all states. These data provide evidence that mechanically opposing inspiratory and expiratory pharyngeal muscles are reciprocally controlled and their response to negative pressure are state dependent.

A reversible structural interconversion involving [M(H2pdc)2(H2O)2] . 2H2O (M = Mn, Fe, Co, Ni, Zn, H3pdc = 3,5-pyrazoledicarboxylic acid) and the role of a reactive intermediate [Co(H2pdc)2]

A new type of hydrogen bonded networks [M(H2pdc)2(H2O)2] . 2H2O [M = Mn (1), Fe (2), Co (3), Ni (4), Zn (5); H3pdc = 3,5-pyrazoledicarboxylic acid] have been synthesized via hydrothermal reactions and their structures have been characterized. Upon a cooling-heating cycle, these compounds undergo a reversible structural interconversion process via hydration-dehydration: [chemical equation: see text]. The process is associated with distinct color changes. The dehydrated [M(H2pdc)2] (M = Mn, Fe, Co, Ni, and Zn) are amorphous and highly reactive. Further chemical reactions of these reactive intermediates show that they may act as effective precursors towards assembly of new supramolecular compounds that may otherwise be inaccessible by other synthetic routes. An interesting structure containing an "open-box" molecule [Co4(Hpdc)4(py)12] . 4py . 2H2O . 2CH3OH (6) (py=pyridine) has been isolated by using dehydrated [Co(H2pdc)2] as the precursor, and its crystal structure has been analyzed. Crystal data for 1-6: monoclinic, space group P2(1/c) and Z = 2 with a = 10.186(2), b = 12.473(2), c = 6.831(1) A, beta = 108.80(3) degrees (1); a = 9.896(2), b = 12.402(2), c = 6.810(1) A, beta = 108.15(3) degrees (2); a = 9.981(2), b = 12.426(2), c = 6.807(1) A, beta = 108.23(3) degrees (3); a = 9.896(2), b = 12.402(2), c = 6.810(1) A, beta = 108.15(3) degrees (4); a = 10.001(2), b = 12.430(2), c = 6.834(1) A, beta = 108.32(3) degrees (5); a = 9.9617(1), b=18.5080(2), c = 28.4786(3) A, beta = 93.076(1) degrees (6).

Infertility and testicular defects in hormone-sensitive lipase-deficient mice

The 84-kDa hormone-sensitive lipase (gene designation Lipe; EC 3.1.1.3) is a cholesterol esterase and triglyceride hydrolase that functions in the release of fatty acids from adipocytes. The role of hormone-sensitive lipase in other tissues such as the testis, where a specific 120-kDa testis-specific isoform is expressed, is unknown. To study this, we examined the fertility and testicular histology of gene-targeted hormone-sensitive lipase-deficient mice. Homozygous hormone-sensitive lipase-deficient male mice are infertile and have decreased testis weights; female homozygotes are fertile. Testicular abnormalities, detected at the light and electron microscopic levels, included the presence of multinucleated round and elongating spermatids, vacuolization of the seminiferous epithelium, asynchronization of the spermatogenic cycle, sloughing of postmeiotic germ cells from the seminiferous epithelium into the lumen, and a marked reduction in the numbers of late spermatids. Extensive nuclear head deformation was noted in late spermatids as well as the sharing of a common acrosome in multinucleated cells. In some multinucleated cells, nuclei were separated from their acrosomes, with the acrosomes remaining attached to areas of ectoplasmic specializations, suggesting defects in intercellular cytoplasmic bridge integrity. Although the lumen of the epididymis was essentially devoid of spermatozoa and filled instead with spherical degenerating cells, the epididymal epithelial cells appeared normal. The few late spermatids present in the epididymis were abnormal. There was no morphological evidence, as judged by the absence of lipid droplets of triacylglycerol or cholesteryl ester accumulation in the testis. Together, the data suggest that hormone-sensitive lipase deficiency results in abnormalities in spermiogenesis that are incompatible with normal fertility. We speculate that a metabolite downstream from the hormone-sensitive lipase reaction may be essential for membrane stabilization and integrity in the seminiferous epithelium and, in particular, may play an important role in the maintenance of intercellular cytoplasmic bridges between postmeiotic germ cells.

[Surgical procedure of gynecologic malignances in patients over 70 years]

OBJECTIVE

To assess the viability of performing surgical procedure on gynecologic malignances patients over 70 years old.

METHODS

A retrospective study of all patients 70 years of age and older treated by surgical procedure for gynecologic malignances was performed between September 1, 1983, and June 30, 1999.

RESULTS

Fifty-seven patients were older than 70 years of age at the time of the diagnosis. Mean age of the patients was 73.5 years. In thirty-four patients a extensive surgical procedure was carried out, while in twenty-three patients a conservative surgery was done. Seventy-one percent of patients had one or more preexisting medical illnesses. Minor surgical morbidity occurred in 31.6% of the patients, while major surgical morbidity occurred in 10.5% of the patients. There were no differences in the type of surgical procedure, mean hospital stay, preexisting medical illness and postoperative complication between patients 70 to 75 and over age 75. The total major postoperative complications occurred in extensive surgical procedure group and postoperative mean stay was also significantly length.

CONCLUSIONS

The extensive surgical procedure is a safe treatment for elderly patients with gynecologic malignances. Careful preoperative assessment, monitoring, and meticulous postoperative care are vital to the success.

Novel silver(I)-organic coordination polymers: conversion of extended structures in the solid state as driven by argentophilic interactions

Structurally distinct coordination polymers [Ag(bpp)]ClO4 1 and [Ag(bpp)]PF6 2 [bpp = 1,3-bis(4-pyridyl)propane] have been assembled; the conversion of 1 into 2 on treatment with NaPF6 is driven by argentophilic interactions and is the first such transformation reported for silver(I)-organic coordination polymers.

A genetic investigation of E2A function in lymphocyte development

Lymphocytes are derived from hematopoietic stem cells (HSC) following a series of regulated differentiation events. Multipotent HSCs become committed to the B cell lineage in bone marrow and the T cell lineage in the thymus after receiving appropriate signals from the corresponding microenvironment. These committed lymphoid cells must then undergo V(D)J recombination at the immunoglobulin gene or T cell receptor gene locus resulting in clonal production of functional B or T lymphocytes, respectively. Lymphocyte commitment and differentiation are accompanied by programmed gene expression or repression events which are driven by lineage and stage specific transcription factors. The basic-helix-loop-helix (bHLH) transcription factors encoded by the E2A gene are involved in several differentiation events during B and T cell development, including lineage commitment, initiation of V(D)J recombination, and antigen receptor mediated proliferation and differentiation. Several recent reviews have provided a comprehensive discussion of biochemical, cellular, and genetic research on E2A function in lymphocyte development (1,2). Here, we only discuss some of the genetic approaches our laboratory (except where it is noted) has undertaken to investigate the molecular pathways mediated by E2A transcription factors in lymphocyte development.

Noise robustness of nonlinear filters for image recognition

We analyze the performance of the Fourier plane nonlinear filters in terms of signal-to-noise ratio (SNR). We obtain a range of nonlinearities for which SNR is robust to the variations in input-noise bandwidth. This is shown both by analytical estimates of the SNR for nonlinear filters and by experimental simulations. Specifically, we analyze the SNR when Fourier plane nonlinearity is applied to the input signal. Using the Karhunen-Loève series expansion of the noise process, we obtain precise analytic expressions of the SNR for Fourier plane nonlinear filters in the presence of various types of additive-noise processes. We find a range of nonlinearities that need to be applied that keep the output SNR of the filter stable relative to changes in the noise bandwidth.

Reversing drug resistance in the ovarian carcinoma cell line SKOV3/mdr1 in vitro by antisense oligodeoxynucleotides

OBJECTIVE

To investigate the effect of multidrug resistance gene 1 (mdr1) antisense oligodeoxynucleotides (ODNs) on reversing multidrug resistance in the drug resistant ovarian carcinoma cell line SKOV3/mdr1.

METHODS

The ovarian carcinoma cell line SKOV3 transducted with a human multidrug resistance gene (mdr1) served as the drug resistant model (SKOV3/mdr1). The mdr1 antisense ODNs was transfected into SKOV3/mdr1 cells while mediated by lipofectamine. Reverse transcription-polymerase chain reaction (RT-PCR) was used to measure the expression and the amount of the mdr1 mRNA in the cells. The positive rate and function of the mdr1 gene product P-glycoprotein (Pgp) in the mdr1 antisense ODNs treated SKOV3/mdr1 cells were determined by flow cytometry and rhodamine 123 efflux. Drug resistance in the SKOV3/mdr1 cell line was observed by MTT assay and cell colony culture.

RESULTS

The mdr1 mRNA level was decreased to about 60% of that of beta-actin after mdr1 antisense ODNs treatment. The Pgp positive rate of mdr1 antisense ODNs treated SKOV3/mdr1 cells decreased from 100% to 52.6% (P < 0.01). The intracellular rhodamine 123 retention was increased from 9.1% to 33.8% (P < 0.01). The chemoresistance to taxol decreased to 58% of SKOV3/mdr1 with mdr1 antisense ODN treatment. Compared with SKOV3/mdr1 cells in the control group, under a certain range of drug concentrations, the number of drug resistance colonies in mdr1 antisense ODNs treated SKOV3/mdr1 cells for taxol and doxorubicin decreased by 8.6 +/- 0.8 fold and 3.1 +/- 0.6 fold, respectively. Some non-specific functions during oligodeoxyncleotide treatment was also detected.

CONCLUSION

mdr1 expression in the SKOV1/mdr1 cell line was partially inhibited after mdr1 antisense ODNs treatment at the mRNA and protein level, increasing the chemotherapy sensitivity of this drug resistant ovarian carcinoma cell line.

An Abd-B class HOX.PBX recognition sequence is required for expression from the mouse Ren-1c gene

Expression from the mouse Ren-1(c) gene in As4.1 cells is dependent on a proximal promoter element (PPE) located at approximately -60 and a 241-base pair enhancer region located at -2625 relative to the transcription start site. The PPE (TAATAAATCAA) is identical to a consensus HOX.PBX binding sequence. Further, PBX1b has been shown to be a component of a PPE-specific binding complex present in nuclear extracts from As4.1 cells. The binding affinities of different paralog HOX members to the PPE were examined in the absence or presence of PBX1b. HOXB6, -B7, and -C8 failed to bind the PPE alone but showed weak affinity in the presence of PBX1b. In contrast, HOXD10 and to a lesser degree HOXB9 bound the PPE with high affinities regardless of whether PBX1b was present. Abd-B HOX members, including HOXD10, -A10, -A9, -B9, and -C9, are expressed in As4.1 cells. The ability of HOX and PBX1b to form a ternary complex with PREP1 on the PPE is also demonstrated both in vivo and in vitro. Point mutations in either the HOX or PBX half-site of the PPE disrupted the formation of the HOX.PBX complex and dramatically decreased transcriptional activity of the Ren-1(c) gene demonstrating that both the HOX and PBX half-sites are critical for mouse renin gene expression. These results strongly implicate Abd-B class Hox genes and their cofactors as major determinants of the sites of renin expression.

Use of an in silico approach to define the gene structure of eukaryotic adenylyl cyclases

The limited information available regarding the gene structure of adenylyl cyclases (AC), which catalyze the synthesis of cAMP, suggests a complex arrangement with many exons and large introns such that molecular techniques to define these gene structures are time- and labor-intensive. We report here the use of a computer-based approach involving the assembly of fragmented sequence data generated by the Human Genome Project and nucleic acid analysis software to decipher the gene structure of human and murine AC 6 and other human AC isoforms (ACs 3, 7, and 8). The results, which document 21 exons in human and murine AC 6, human AC 3, 18 exons in AC 8, and 24 exons in AC 7, show substantial conservation of exon organization in the AC family and in particular regions of the AC protein. Application of such in silico methods should prove useful to characterize genes for other ACs and protein families and data provided here should facilitate studies of polymorphisms in AC genes.

Evaluation of a single-pass intestinal-perfusion method in rat for the prediction of absorption in man

Prediction of the fraction of dose absorbed from the intestine (Fa) in man is essential in the early drug discovery stage. In-vitro assays in Caco-2 and MDCK cells are routinely used for that purpose, and their predictive value has been reported. However, in-situ techniques might provide a more accurate estimation of Fa. In this study, we evaluated a single-pass intestinal-perfusion (SPIP) method in the rat for its use in the prediction of absorption in man and compared it with a previous report using cell-based assays. Effective permeability coefficients (Peff) were determined in rats for 14 compounds, and ranged from 0.043x 10(-4) cm s(-1) to 1.67 x 10(-4) cm s(-1). These values strongly correlated (r2 = 0.88) with reported Peff values for man. In addition, the Spearman rank correlation coefficient calculated for in-situ-derived Peff and absorption in man was 0.92 while for the previously tested in-vitro Caco-2 and MDCK systems vs absorption in man, the correlation coefficients were 0.61 and 0.59, respectively. SPIP provided a better prediction of human absorption than the cell-based assays. This method, although time consuming, could be used as a secondary test for studying the mechanisms governing the absorption of new compounds, and for predicting more accurately the fraction absorbed in man.

[In vitro cotransfer human multidrug resistance gene (mdr-1) and dihydrofolate reductase gene (DHFR) into human CD(34)(+) progenitor cells to broaden the spectrum of drug resistance]

OBJECTIVE

To explore the feasibility of cotransferring human mdr-1 gene and DHFR gene into human CD(34)(+) progenitor cells to broaden the spectrum of drug resistance and improve the tolerance of myelosuppression following combination chemotherapy.

METHODS

The recombinant retroviral vector pSF-DIM containing mdr-1 and DHFR (L22Y) gene was constructed by introducing IRES sequence into vector FMCF which enable highly efficient gene expression in early hematopoietic cells. The retrovirus titers were raised by repeated supernatant cross infection between the amphotropic and ectropic retroviral packaging cells. Human CD(34)(+) progenitor cells were transduced by supernatant infection. Expression of P-gp was detected by flow cytometry. Integration of the foreign drug resistance gene in CD(34)(+) cells was determined by PCR. Drug resistance was evaluated by CFU-GM assay.

RESULT

Integration of the two foreign drug resistance genes was detected in the CD(34)(+) cells after pSF-DIM transduction. Compared with the untransduced group, the expression of P-gp elevated by 10.98% after gene transduction and the CFU-GM yields were significantly increased at 48 nmol/L of MTX and 10 ng/ml or 12 ng/ml of taxol (P < 0.05).

CONCLUSION

The retroviral vector pSF-DIM can mediate mdr-1 and DHFR gene integration and co-expression in human hematopoietic progenitor cells so as to broaden the spectrum of drug resistance.

Thermolysis of free-radical initiators: tert-butylazocumene and its 1,3- and 1,4-bisazo and 1,3,5-trisazo analogues

Four tert-butylazocumenes (4-7) were prepared from the corresponding cyanobenzenes, and their nitrogen evolution kinetics and products were analyzed. In combination with TEMPO, the simplest compound, tert-butylazocumene (4), shows promise as a "one-radical" initiator of styrene polymerization. The ABNO-trapped cumyl radical 29 is a particularly stable trialkylhydroxylamine, whose thermolysis half-life is 2.1 h at 150 degrees C. Taking advantage of this stability, we trapped the cumyl radical centers from 7 to afford tris adduct 32a. While the behavior of the meta bisazoalkane 6 can be mostly predicted from that of 4, the para isomer 5 exhibits both unusual products and kinetics, attributed to the formation of quinodimethane 33 via azo-containing radical 34. In fact, flash vacuum pyrolysis of 5 allowed observation of the (1)H and (13)C NMR spectra of 33, whose persistence even at ambient temperature showed that this quinodimethane is far more stable than the parent 36. Finally, evidence is presented that 7 is an initiator of star polymerization.

Ephrin-B3 is the midline barrier that prevents corticospinal tract axons from recrossing, allowing for unilateral motor control

Growing axons follow highly stereotypical pathways, guided by a variety of attractive and repulsive cues, before establishing specific connections with distant targets. A particularly well-known example that illustrates the complexity of axonal migration pathways involves the axonal projections of motor neurons located in the motor cortex. These projections take a complex route during which they first cross the midline, then form the corticospinal tract, and ultimately connect with motor neurons in the contralateral side of the spinal cord. These obligatory contralateral connections account for why one side of the brain controls movement on the opposing side of the body. The netrins and slits provide well-known midline signals that regulate axonal crossings at the midline. Herein we report that a member of the ephrin family, ephrin-B3, also plays a key role at the midline to regulate axonal crossing. In particular, we show that ephrin-B3 acts as the midline barrier that prevents corticospinal tract projections from recrossing when they enter the spinal gray matter. We report that in ephrin-B3(-/-) mice, corticospinal tract projections freely recross in the spinal gray matter, such that the motor cortex on one side of the brain now provides bilateral input to the spinal cord. This neuroanatomical abnormality in ephrin-B3(-/-) mice correlates with loss of unilateral motor control, yielding mice that simultaneously move their right and left limbs and thus have a peculiar hopping gait quite unlike the alternate step gait displayed by normal mice. The corticospinal and walking defects in ephrin-B3(-/-) mice resemble those recently reported for mice lacking the EphA4 receptor, which binds ephrin-B3 as well as other ephrins, suggesting that the binding of EphA4-bearing axonal processes to ephrin-B3 at the midline provides the repulsive signal that prevents corticospinal tract projections from recrossing the midline in the developing spinal cord.

Myosin light chain kinase regulates capacitative ca(2+) entry in human monocytes/macrophages

Monocytes/macrophages are present in all stages of atherosclerosis. Although many of their activities depend to various extents on changes in intracellular Ca(2+) concentration ([Ca(2+)](i)), mechanisms regulating [Ca(2+)](i) in these cells remain unclear. We aimed to explore the role of myosin light chain kinase (MLCK) in Ca(2+) signaling in freshly isolated human monocytes/macrophages. Large capacitative Ca(2+) entry (CCE) was observed under fura 2 fluoroscopy in human monocytes/macrophages treated with thapsigargin and cyclopiazonic acid. ML-9 and wortmannin, 2 structurally different inhibitors of MLCK, dose-dependently (1 to 100 micromol/L) prevented CCE and completely did so at 100 micromol/L, whereas inhibitors of tyrosine kinase and protein kinase C had only partial effects. Western blotting showed that thapsigargin significantly caused myosin light chain phosphorylation, which was almost completely blocked by ML-9 (100 micromol/L) and wortmannin (100 micromol/L). ML-9 also dose-dependently (1 to 100 micromol/L) inhibited this phosphorylation, which was well correlated with its inhibition of CCE. Transfection with MLCK antisense completely prevented CCE in response to thapsigargin and cyclopiazonic acid, whereas MLCK sense had no effect. These data strongly indicate that MLCK regulates CCE in human monocytes/macrophages. The study suggests a possible involvement of MLCK in many Ca(2+)-dependent activities of monocytes/macrophages.

Comparison of chromatographic and spectroscopic methods used to rank compounds for aqueous solubility

Rapid methods for ranking the solubility of compounds in aqueous media using commercial, 96-well ultraviolet-visible (UV-vis) and nephelometric plate readers are described. The methods were evaluated using commercially available compounds from a variety of structural classes as well as a series of structurally related compounds derived from combinatorial synthesis. Samples were predissolved in dimethyl sulfoxide (DMSO) and then added to the study solvent to attain a final concentration of DMSO in the aqueous solution of 5%. Comparison of filtration of the samples through nylon and poly(tetrafluoroethylene) (PTFE) membranes is also described. The solubility of the compounds determined using the UV-vis plate reader in the absorption mode (with samples filtered with the PTFE filter) as well as in the light scattering mode was in good agreement with that determined by high-performance liquid chromatography, with an average correlation of 0.95. Solubility data obtained using a 96-well nephelometer was also comparable (r(2) = 0.97). The nonequilibrium methods described in this study can be used to rapidly rank compounds from combinatorial libraries for solubility and can also give a general assessment of solubility prior to running additional high throughput screens in a drug discovery environment.

The effect of pH on the dimensionality of coordination polymers

Hydrothermal reactions of simple alkaline salts or their hydroxides with 3,5-pyrazoledicarboxylic acid (H(3)pdc) yielded seven new compounds. At a lower pH level three one-dimensional structures [Ca(Hpdc)(H(2)O)(4)].2H(2)O (1), [Ca(Hpdc)(H(2)O)(4)].H(2)O (2), and [Ba(H(2)pdc)(2)(H(2)O)(4)].2H(2)O (6) were obtained by evaporation of the solutions resulting from hydro(solvo)thermal reactions of MCl(2) (M = Ca, Ba) with H(3)pdc in water (1, 6) or in water/Et(3)N (2) at 150 degrees C for 3 days. Crystal structures of 1 and 2 contain zigzag chains of metal centers bridged by a single Hpdc(2-) ligand, whereas structure 6 consists of linear chains of metal centers bridged by two H(2)pdc(-) ligands. A dimer molecule [Sr(H(3)pdc)(H(2)pdc)(2)(H(2)O)(3)](2).2(H(3)pdc).4H(2)O (4) was obtained from a similar hydrothermal reaction using Sr(ClO(4))(2).6H(2)O instead of MCl(2). This compound contains [2+2] metallomacrocycles. At higher pH levels (pH = 4-6), the three-dimensional polymers [M(Hpdc)(H(2)O)] (Ca 3, Sr 5, Ba 7 ) were isolated by reactions of MCl(2) (M = Ca, Sr, Ba) with H(3)pdc in water/Et(3)N or in M(OH)(2) (M = Ca, Sr, Ba) with H(3)pdc in water under hydro(solvo)thermal conditions (150 degrees C, 3 days). Calcium and strontium are seven- and nine-coordinated in 3 and 5, respectively; barium is nine- and ten-coordinated in 7. It was observed that the increase in pH resulted in a higher connectivity level of ligands, which in turn leads to a higher dimensionality of the crystal structures. The correlation between the structures and pH values will be discussed. Crystal data: for 1, monoclinic, space group P2(1)/n (No. 14), with a = 8.382(2), b = 12.621(3), c = 11.767(2) A, beta = 98.91(3) degrees, Z = 4; for 2, 3, and 5, monoclinic, space group P2(1)/c (No. 14), Z = 4, a = 7.711(2), b = 15.574(3), c = 9.341(2) A, beta = 96.73(3) degrees, Z = 4 (2), a = 6.616(1), b = 12.654(3), c = 8.782(2) A, beta = 103.65(3) degrees, Z = 4 (3), a = 9.213(2), b = 12.088(3), c = 6.196(2) A, beta = 98.96(3) degrees (5); for 4 and 7, triclinic, space group P1 (No. 2), with a = 11.263(2), b = 11.460(3), c = 12.904(2) A, alpha = 71.54(3), beta = 98.96(3), gamma = 89.03(3) degrees, Z = 1 (4), a = 7.107(1), b = 9.780(2), c = 11.431(2) A, alpha = 74.69(3), beta = 73.39(3), gamma = 85.29(3) degrees, Z = 2 (7); for 6, monoclinic, space group C2/c (No. 15), with a = 20.493(4), b = 6.708(1), c = 15.939(3) A, beta = 123.56(3) degrees, Z = 4.

Ephrin-B2 selectively marks arterial vessels and neovascularization sites in the adult, with expression in both endothelial and smooth-muscle cells

The Eph receptor tyrosine kinases and their membrane-tethered ephrin ligands provide critical guidance cues at points of cell-to-cell contact. It has recently been reported that the ephrin-B2 ligand is a molecular marker for the arterial endothelium at the earliest stages of embryonic angiogenesis, while its receptor EphB4 reciprocally marks the venous endothelium. These findings suggested that ephrin-B2 and EphB4 are involved in establishing arterial versus venous identity and perhaps in anastamosing arterial and venous vessels at their junctions. By using a genetically engineered mouse in which the lacZ coding region substitutes and reports for the ephrin-B2 coding region, we demonstrate that ephrin-B2 expression continues to selectively mark arteries during later embryonic development as well as in the adult. However, as development proceeds, we find that ephrin-B2 expression progressively extends from the arterial endothelium to surrounding smooth muscle cells and to pericytes, suggesting that ephrin-B2 may play an important role during formation of the arterial muscle wall. Furthermore, although ephrin-B2 expression patterns vary in different vascular beds, it can extend into capillaries about midway between terminal arterioles and postcapillary venules, challenging the classical conception that capillaries have neither arterial nor venous identity. In adult settings of angiogenesis, as in tumors or in the female reproductive system, the endothelium of a subset of new vessels strongly expresses ephrin-B2, once again contrary to earlier views that such new vessels lack arterial/venous characteristics and derive from postcapillary venules. While earlier studies had focused on a role for ephrin-B2 during the earliest embryonic stages of arterial/venous determination, our current findings using ephrin-B2 as an arterial marker in the adult challenge prevailing views of the arterial/venous identity of quiescent as well as remodeling adult microvessels and also highlight a possible role for ephrin-B2 in the formation of the arterial muscle wall.

The adipose tissue phenotype of hormone-sensitive lipase deficiency in mice

OBJECTIVE

To directly ascertain the physiological roles in adipocytes of hormone-sensitive lipase (HSL; E.C. 3.1.1.3), a multifunctional hydrolase that can mediate triacylglycerol cleavage in adipocytes.

RESEARCH METHODS AND PROCEDURES

We performed constitutive gene targeting of the mouse HSL gene (Lipe), subsequently studied the adipose tissue phenotype clinically and histologically, and measured lipolysis in isolated adipocytes.

RESULTS

Homozygous HSL-/- mice have no detectable HSL peptide or cholesteryl esterase activity in adipose tissue, and heterozygous mice have intermediate levels with respect to wild-type and deficient littermates. HSL-deficient mice have normal body weight but reduced abdominal fat mass compared with normal littermates. Histologically, both white and brown adipose tissues in HSL-/- mice show marked heterogeneity in cell size, with markedly enlarged adipocytes juxtaposed to cells of normal morphology. In isolated HSL-/- adipocytes, lipolysis is not significantly increased by beta3-adrenergic stimulation, but under basal conditions in the absence of added catecholamines, the lipolytic rate of isolated HSL-/- adipocytes is at least as high as that of cells from normal controls. Cold tolerance during a 48-hour period at 4 degrees C was similar in HSL-/- mice and controls. Overnight fasting was well-tolerated clinically by HSL-/- mice, but after fasting, liver triglyceride content was significantly lower in HSL-/- mice compared with wild-type controls.

CONCLUSIONS

In isolated fat cells, the lipolytic rate after beta-adrenergic stimulation is mainly dependent on HSL. However, the observation of a normal rate of lipolysis in unstimulated HSL-/- adipocytes suggests that HSL-independent lipolytic pathway(s) exist in fat. Physiologically, HSL deficiency in mice has a modest effect under normal fed conditions and is compatible with normal maintenance of core body temperature during cold stress. However, the lipolytic response to overnight fasting is subnormal.

Polymerase chain reaction detection of Kaposi's sarcoma-associated herpesvirus-optimized protocols and their application to myeloma

Since its discovery in 1994, KSHV (also called human herpesvirus-8 or HHV8) has been implicated in a variety of disorders. Although the association of KSHV with Kaposi's sarcoma (KS), primary effusion lymphoma (PEL), and multicentric Castleman's disease has been well established, its presence in some other diseases, such as multiple myeloma, remains controversial. Because most KSHV studies are based on polymerase chain reaction (PCR) analysis, the conflicting data may be attributable to variations in the methods, primer sets, and target sequences selected. To establish an efficient and reliable PCR approach for KSHV detection we designed eight sets of primers to six regions (ORFK1, ORFK2, ORFK9, ORK26, ORF72, and ORF74) of the KSHV genome using appropriate database and software. The detection sensitivity of these primers was carefully assessed and their reliability was strictly validated in a series of positive (15 KS and PEL samples) and negative (16 lymphoid tissues) controls. We found that primer sets to the ORFK9 region showed the highest sensitivity, whereas primer sets to ORFK1 and ORF74 showed the lowest sensitivity. Primer sets to ORFK9, ORF26 and ORF72 regions detected all of the positive cases, whereas other primer sets showed varying detection rates or nonspecific bands. All 16 negative controls were negative with all primer sets. However, six of 16 negative controls became positive when we used nested PCR targeting ORF26. Therefore, multiple target KSHV sequences increase the detection efficiency, while nested PCR protocols are likely to introduce false positivity. Using ORFK9, ORF26 and ORF72 primer sets, we screened bone marrow biopsies from 18 cases of multiple myeloma, and failed to detect any KSHV sequences. This finding supports the conclusion that KSHV is not associated with multiple myeloma. Indeed, our results further confirm that although KSHV is universally present in Kaposi's sarcoma and primary effusion lymphoma, it is not ubiquitious.