Multi-Omics Reveals the Role of Osteopontin/Secreted Phosphoprotein 1 in Regulating Ovarian Aging

Secreted phosphoprotein 1 (SPP1), also known as osteopontin (OPN), is located on chromosome 4q22.1. This multifunctional secreted acidic glycoprotein is expressed intracellularly and extracellularly in various tissues, where it interacts with regulatory proteins and pro-inflammatory immune chemokines, contributing to the pathogenesis of multiple diseases. Nevertheless, the intricate genetic connections between SPP1 and ovarian aging remain largely unexplored. This study aims to bridge this knowledge gap by delving into ovarian aging and its associations with SPP1 using multi-omics data analysis. Our findings indicate that SPP1 is a potential gene related to ovarian aging. To comprehend the role of SPP1, we conducted spatial transcriptomic analyses on young and aged female mouse ovaries, revealing a significant decline in SPP1 expression in the aging group compared to the young group. Similarly, a significantly low level of SPP1 was found in the 73-year-old sample. Additionally, in-depth single-cell RNA-sequencing analysis identified associations between SPP1 and ITGAV, ITGB1, CD44, MMP3, and FN1. Notably, co-expression analysis highlighted a strong correlation between SPP1 and ITGB1. In summary, this study pioneers the identification of SPP1 as a gene implicated in ovarian aging. Further research into the role of SPP1 has the potential to advance precision medicine and improve treatment strategies for ovarian aging-related conditions.

Gestalt neurons and emergent properties in visual perception: A novel concept for the transformation from local to global processing

Gestalten in visual perception are defined by emergent properties of the whole, which cannot be predicted from the sum of its parts; rather, they arise by virtue of inherent principles, the Laws of Seeing. This review attempts to assign neurophysiological correlates to select emergent properties in motion and contour perception and proposes parallels to the processing of local versus global attributes by classical versus contextual receptive fields. The aim is to identify Gestalt neurons in the visual system to account for the Laws of Seeing in causal terms and to explain "Why do things look as they do" (Koffka, 1935, p. 76).

Female Human Papillomavirus Infection Associated with Increased Risk of Ectopic Pregnancy: Early Evidence from Taiwan Population-Based Cohort Study

Background: This is an investigation of the human papillomavirus (HPV) infection and its correlation with the risk of ectopic pregnancy (EP). Methods: The cohort study includes 11,239 patients with newly diagnosed HPV infections between 2000 and 2012, and by using computer-generated random numbers, patients who do not have HPV infections are selected randomly as the comparison cohort. The HPV infection cohort is matched to comparison individuals at a 1:10 ratio by age and index year. All individuals included in the study were followed up to the point they developed EP, pulled-out from the insurance program, lost to follow-up, or until the end of 2013. A Cox proportional-hazards regression analysis was used to analyze the risk of EP with the hazard ratios (HRs) and 95% confidence intervals (CIs) between the HPV and control cohort. Results: The adjusted hazard ratio (aHR) of EP for HPV patients relative to controls is 1.70 (95% CI = 1.04, 2.78), indicating a positive correlation between EP and HPV in the 13-year follow-up period, after adjusting for age and relevant comorbidities. The sensitivity analyses yield similar results. Conclusions: A history of HPV infection is a potential risk factor associated with the development of subsequent EP in Taiwanese individuals, especially those diagnosed with an HPV infection within 3 years.

Emotional sensitivity predicts internship performance of medical students enrolled under different admission screening protocols

BACKGROUND AND PURPOSE

People with heightened emotional sensitivity can perceive better how others feel. Students admitted to medical school by interviews for assessing pre-set personal qualities, such as emotional sensitivity, may be more likely to meet patients' satisfaction in the future. We tested whether a student enrolled by passing the interview would have more emotional sensitivity than those by taking an exam. We also investigated what impact the enrolment protocols might have on students' internship performance.

METHODS

Participants were first- and second-year medical students and assigned into the interviewed group or examined group according to the entrance protocols. Two emotion-related tasks and one control task were adopted. Subsequently, the performance evaluation of clinical work from students' advisors about these two groups of participants were collected after they finished the internship training at the hospital.

CONCLUSIONS

Students selected through the pre-programmed interview which is based on personal qualities showed greater emotional sensitivity than those selected by the exam. Those students with better emotional sensitivity also performed better when they were in the internship training. Emotional sensitivity is a valid index to predict students' future performance and could be used in the selection protocol for medical students.

Female Human Papillomavirus Infection Associated with Increased Risk of Infertility: A Nationwide Population-Based Cohort Study

Objective. This study investigated whether women with a history of human papillomavirus (HPV) infection have an increased risk of infertility. Material and Methods. All patients with an HPV infection (n = 11,198) in Taiwan’s National Health Insurance Research Database (2000–2012) were propensity score matched with control subjects (n = 11,198) without an HPV infection by age, sex, index year, and relevant co-morbidities. Both groups were tracked until a diagnosis of infertility was recorded. The Chi-square test was used to analyze the distribution of demographic characteristics in the HPV group and non-HPV group. A Cox proportional hazards regression was used to estimate the hazard ratios (HRs) for the development of infertility, adjusting for age, sex, and co-morbidities. The Kaplan–Meier method was used to plot the cumulative incidence curves. We also performed negative controls to test for possible unmeasured confounding. Results. The HPV cohort had a higher risk of infertility. The adjusted HR (aHR) was found to be 1.39 (95% CI = 1.19–1.63) after adjusting for demographic characteristics and relevant co-morbidities. In the age subgroup analysis, patients with an HPV infection had an increased risk of infertility compared to the non-HPV cohort in the group aged 26 to 35 years (aHR, 1.53; 95% CI = 1.24–1.88). As we used propensity score matching to treat measurable confounders and negative controls to access unmeasured confounders, the findings of the study are robust. Conclusions. Among females of reproductive age, HPV infection is a potential risk factor that predisposes individuals to subsequent infertility.

Maternal pregnancy-induced hypertension increases the subsequent risk of transient tachypnea of the newborn: A nationwide population-based cohort study

OBJECTIVE

To determine the association between pregnancy-induced hypertension (PIH) and transient tachypnea of the newborn (TTN) and to identify the predictive risk factors.

MATERIALS AND METHODS

Pregnant women with a newly diagnosed PIH (between 2000 and 2013) from the Taiwan National Health Insurance Research Database (NHIRD) were compared with a matched (with respect to age and year of delivery) cohort of pregnant women without PIH. The occurrence of TTN was evaluated in both cohorts.

RESULTS

Among the 23.3 million individuals registered in the NHIRD, 29,013 patients with PIH and 116,052 matched controls were identified. According to a multivariate analysis, PIH (odds ratio [OR] = 1.85, 95% confidence interval [CI] = 1.69-2.03, p < 0.0001), age ≥ 30 years (OR = 1.38, 95% CI = 1.26-1.51, p < 0.0001), primiparity (OR = 1.37, 95% CI = 1.24-1.5, p < 0.0001), preterm birth (OR = 3.4, 95% CI = 3.09-3.75, p < 0.0001), multiple births (OR = 2.54, 95% CI = 2.24-2.89, p < 0.0001), and cesarean section (OR = 1.71, 95% CI = 1.56-1.88, p < 0.0001) were independent risk factors for the development of TTN.

CONCLUSION

Women with PIH have an increased risk of having infants who develop TTN compared with those without PIH. Additionally, age ≥30 years, primiparity, preterm birth, multiple births, and cesarean section were independent risk factors for the development of TTN.

Impact of putamen stroke on task context updating: Evidence from P300 brain waves

According to the context updating theory, the oddball P300 component indexes brain activities underlying revision of the mental representation induced by incoming stimuli. It involves an attention-driven comparison process that evaluates the representation of the previous event in working memory. Delayed latencies have been reported for various types of stroke such as unilateral thalamic stroke. We investigated memory updating effects in patients with putamen stroke. Two groups of patients with putamen and thalamic stroke were recruited along with two control groups of young and old healthy participants. Auditory and visual P300 were elicited respectively in a two-stimulus oddball paradigm. The auditory P300 peak latencies were significantly longer in patients with a putamen lesion than in the aged and young control groups and the same pattern was found in the thalamus-lesioned patient. The delayed auditory P300 component in both patient groups but neither control group suggests impairment of memory updating in patients with putamen stroke comparable with thalamic stroke. Our study illustrates the important role of subcortical structures subserved in context updating.

Predicting raters' transparency judgments of English and Chinese morphological constituents using latent semantic analysis

The morphological constituents of English compounds (e.g., "butter" and "fly" for "butterfly") and two-character Chinese compounds may differ in meaning from the whole word. Subjective differences and ambiguity of transparency make judgments difficult, and a computational alternative based on a general model might be a way to average across subjective differences. In the present study, we propose two approaches based on latent semantic analysis (Landauer & Dumais in Psychological Review 104:211-240, 1997): Model 1 compares the semantic similarity between a compound word and each of its constituents, and Model 2 derives the dominant meaning of a constituent from a clustering analysis of morphological family members (e.g., "butterfingers" or "buttermilk" for "butter"). The proposed models successfully predicted participants' transparency ratings, and we recommend that experimenters use Model 1 for English compounds and Model 2 for Chinese compounds, on the basis of differences in raters' morphological processing in the different writing systems. The dominance of lexical meaning, semantic transparency, and the average similarity between all pairs within a morphological family are provided, and practical applications for future studies are discussed.

Anti-inflammatory properties of yellow and orange pigments from Monascus purpureus NTU 568

The Monascus species has been used in foods for thousands of years in China. In this study, 10 azaphilone pigments, including four yellow and six orange pigments, were isolated from the fermented rice and dioscorea of Monascus purpureus NTU 568. By employing lipopolysaccharide (LPS)-stimulated murine macrophage RAW 264.7 cells, we determined the inhibitory activities of these pigments on nitric oxide (NO) production. As a result, four orange pigments, monaphilols A-D, showed the highest activities (IC50 = 1.0-3.8 μM), compared with the other two orange pigments, monascorubrin (IC50 > 40 μM) and rubropunctatin (IC50 = 21.2 μM), and the four yellow pigments ankaflavin (IC50 = 21.8 μM), monascin (IC50 = 29.1 μM), monaphilone A (IC50 = 19.3 μM), and monaphilone B (IC50 = 22.6 μM). Using Western blot and ELISA kits, we found that treatments with 30 μM of the yellow pigments and 5 μM of the orange pigments could down-regulate the protein expression of inducible nitric oxide synthase (iNOS) and suppress the production of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6). We also used two animal experiments to evaluate the anti-inflammatory effects of these pigments. In a 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema model, eight of these pigments (0.5 mg/ear) could prevent ear edema against TPA administrations on the ears of BALB/c mice. In an LPS-injection mice model, several of these pigments (10 mg/kg) could inhibit the NO, TNF-α, IL-1β, and IL-6 levels in the plasma of BALB/c mice. As concluded from the in vitro and in vivo studies, six azaphilonoid pigments, namely, ankaflavin, monaphilone A, and monaphilols A-D, showed high potential to be developed into chemopreventive foods or drugs against inflammation-associated diseases.

Protective effect of deferricoprogen isolated from Monascus purpureus NTU 568 on citrinin-induced apoptosis in HEK-293 cells

Monascus species have traditionally been used in Asian food, with rice as their fermentation substrate. Red mold rice (RMR) contains citrinin, a nephrotoxic agent capable of exerting oxidative stress and cellular apoptosis. We investigated the components in RMR that could minimize the adverse effects of citrinin. Combining chemical separations and bioactivity assays, we identified an antioxidative component called deferricoprogen (DFC) in the fermented rice of Monascus purpureus NTU 568. The DFC structure was confirmed by nuclear magnetic resonance (NMR) and mass spectra analysis. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical-scavenging activity of DFC was similar to that of vitamin E. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay and flow cytometric analysis showed the effect of DFC and citrinin on cell viability and cell cycle. DFC was found to be protective against the cytotoxicity and cell death induced by citrinin on human embryonic kidney (HEK-293) cells. DFC also demonstrated anti-apoptotic property in preventing citrinin-induced apoptosis.

Induction of apoptosis in human breast adenocarcinoma cells MCF-7 by monapurpyridine A, a new azaphilone derivative from Monascus purpureus NTU 568

A new azaphilonidal derivative, monapurpyridine A (MPA), has recently been isolated from the fermented products of Monascus purpureus NTU 568. The structure of MPA was elucidated by nuclear magnetic resonance (1H-NMR, 13C-NMR, COSY, HMQC, and HMBC) and other spectroscopic analyses. Biological evaluation revealed that MPA could induce cell death in human breast adenocarcinoma cells MCF-7, and it has no significant toxicity to normal mammary epithelial cells M10. The MTT assay and flow cytometric analysis were employed to investigate cell viability and cell cycle influenced by MPA. Moreover, we used Western blot and caspase activity assay to demonstrate the activation of caspase-3, -8 and -9 resulted from MPA. All evidence supported that MPA was suitable for developing into a chemotherapeutic or chemopreventive agent against breast cancer.

Contribution of intracranial vertebral artery asymmetry to vestibular neuropathy

OBJECTIVES

To test the hypothesis that vertebral artery hypoplasia (VAH) may affect the lateralisation of vestibular neuropathy (VN), probably through haemodynamic effect on the vestibular labyrinth.

METHODS

69 patients with unilateral VN were examined with a magnetic resonance angiographic (MRA) and caloric test. 50 healthy subjects served as controls. The diagnosis of intracranial VAH was based on MRA if <0.22 cm in VA diameter and a diameter asymmetry index >40%. The authors then correlated the canal paretic side with the VAH side.

RESULTS

MRA study revealed 29 VAH (right/left: 23/6) in VN subjects and six VAH in controls (right/left: 5/1). The RR of VAH in VN subjects compared with controls was elevated (RR=2.2; 95% CI 1.8 to 2.8). There was a high accordance rate between the side of VAH and VN. Among 29 patients with unilateral VAH, 65.5% (N=19) had an ipsilateral VN, in which left VAH showed a higher accordance rate (83.3%) than the right side (60.9%). VN subjects with vascular risk factors also had a higher VAH accordance rate (81%) than those without (25%).

CONCLUSIONS

VAH may serve as a regional haemodynamic negative contributor and impede blood supply to the ipsilateral vestibular labyrinth, contributing to the development of VN, which could be enhanced by atherosclerotic risk factors and the left-sided location.

New bioactive orange pigments with yellow fluorescence from Monascus-fermented dioscorea

Red mold dioscorea (RMD) is a fermented product of Monascus purpureus NTU 568 using dioscorea as culture substrate. To investigate the bioactive components of RMD, six orange pigments including four new azaphilones with yellow fluorescence, monapilol A-D (1-4), and known monascorubrin (5) and rubropunctatin (6) were isolated and characterized. Structural elucidation of new isolates was based on nuclear magnetic resonance ((1)H NMR, (13)C NMR, COSY, HMQC, and HMBC) and other spectroscopic analyses. The structures of monapilols (1-4) were similar to those of monascorubrin (5) and rubropunctatin (6); however, the hydroxyl group (8-OH) in compounds 1-4 substituted for the C-8 carbonyl in compounds 5 and 6. Biological evaluation indicated that compounds 1-4 inhibited nitric oxide (NO) production on lipopolysaccharide-stimulated RAW 264.7 cells. Compounds 1-4 also exhibited antiproliferative activities against human laryngeal carcinoma (HEp-2) and human colon adenocarinoma (WiDr).

Anti-tumor and anti-inflammatory properties of ankaflavin and monaphilone A from monascus purpureus NTU 568

An azaphilonidal derivative monaphilone A (MA) was recently isolated from the fermented products of Monascus purpureus NTU 568 by our laboratory. We report here the exploration of apoptosis-related and anti-inflammatory properties of MA and ankaflavin (AK) by some experiments about inducing death of human laryngeal carcinoma cell line HEp-2 and reducing inflammatory responses on murine macrophage RAW 264.7 cells. We employed a ssDNA enzyme-linked immunosorbent assay (ELISA) kit to investigate the nuclear changes of early apoptosis induced by AK and MA on HEp-2 cells and used a western blot and an enzyme activity assay to demonstrate the activation of caspase-3, caspase-8, and caspase-9 by MA and AK. Our studies revealed that AK and MA may decrease lipopolysaccharide (LPS)-induced inflammatory responses, including nitrite productions and expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) in RAW 264.7 cells. All evidence support that azaphilonidal derivatives from M. purpureus NTU 568, such as AK and MA, are suitable for the development of chemotherapy or chemopreventive agents.

Cr(VI) removal on fungal biomass of Neurospora crassa: the importance of dissolved organic carbons derived from the biomass to Cr(VI) reduction

Interactions of toxic Cr(VI) with renewable biomaterials are considered an important pathway for Cr(VI) removal in ecosystems. Biomaterials are susceptible to dissolution, and their dissolved derivatives may provide an alternative to surface-involved pathway for scavenging of Cr(VI). In this study, dissolved organic carbon (DOC) derived from Neurospora crassa biomass was investigated. The proportion of Cr(VI) reduction by DOC to that on biomass was determined to evaluate the importance of DOC to Cr(VI) reduction. A rapid increase in DOC concentration from 145.6 to 193.7 mg L(-1) was observed when N. crassa-biomass was immersed in 0.01 M KCl solution at pH of 1-5, and polysaccharides, peptides, and glycoproteins with carboxyl, amide, and -NH functional groups, are the major compositions of DOC. On reaction of 96.2 microM Cr(VI) with N. crassa-biomass or DOC, it was estimated that DOC contributed approximately 53.8-59.5% of the total Cr(VI) reduction on biomass in the dark. Illumination enhanced Cr(VI) reduction via photo-oxidation of biomass/DOC under aeration conditions, which formed superoxide for Cr(VI) reduction. At pH 1, photoinduced Cr(VI) reduction by DOC proceeded more rapidly than reduction on the biomass surface. However, at pH >3, with a decrease in Cr(VI) reduction by DOC, photon-excited biomass may become an important electron source for Cr(VI) photoreduction.

Monaphilones A-C, three new antiproliferative azaphilone derivatives from Monascus purpureus NTU 568

Monascus purpureus NTU 568 was a mutant strain from M. purpureus HM105. The methanol extract of red mold rice fermented by this strain exhibited four major yellow pigment signals on HPLC profile. By repeated chemical chromatography methods, three new azaphilone derivatives, namely, monaphilone A (1), B (2) and C (3), along with the known pigments ankaflavin (4) and monascin (5), were isolated and characterized. Based on spectroscopic analyses, mainly 1D and 2D NMR data, the structures of compounds 1-3 were completely elucidated; in addition, 1-3 were determined to be new azaphilone structures, due to the decrease of carbon monoxide for producing a gamma-lactone ring, compared with other azaphilone derivatives. Biological evaluations showed that monaphilone A (1) and B (2) exhibited an antiproliferative effect against HEp-2 (human laryngeal carcinoma cell line) and WiDr (human colon adenocarcinoma cell line), and none of the five compounds had toxicity to normal human lung cell lines (WI-38 and MRC-5) at 70 muM.

Abstract 467: Effects of Monascus-fermented rice extract on malignant cell associated neovascularization and intravasation by chicken embryo chorioallantoic membrane model

The traditional Chinese medicine, “Hong-Qu”, also call “red mold rice” in the United States and Europe, has been identified and used for the treatment of blood stasis, a disorder related to hyperlipidemia and atherosclerosis. In addition to its value in improving metabolism syndrome, extracts from Monascus fermented rice inhibited proliferation of various cancer cells in vitro and in vivo have demonstrated previously. The objective of the current study was to examine correlation of red mold rice ethanol extract (RMRE) on the process of angiogenesis, invasion and metastasis during tumor progression. In the current study, we examined the inhibitory effects of SW480 and SW620 human colorectal carcinoma cells by RMRE using in vitro MTT assay. RMRE significantly inhibited the proliferation of SW480 and SW620 cells in dose- and time-dependent manner. However, human umbilical vein endothelial cells (HUVECs) showed a minor reduction effect of cell viability up to 20 µg/mL of RMRE for 48 hours using crystal violet staining assay. The capillary-like network morphology was observed following 20 ng/mL VEGF or SW620 culture-conditional medium (CM) addition. Nevertheless, capillary-like tube formation have failed to show when RMRE participation. Moreover, SW620 cells could growth in Matrigel grafts and spontaneously intravasation from the upper to the lower of chick embryo chorioallantoic membrane (CAM) model, which detected human Alu genomic DNA by PCR amplification from the lower CAMs at RMRE-untreated group. The percentage of neovascularization was increased 75.3±11.6% by SW620 cells onplant with Matrigel grafts on the CAM model. However, addition of RMRE significantly reduced CAM neovascularization in dose-dependent effect. Finally, we have finding that RMRE effectively decreased activity of matrix metalloproteinase (MMP)-7 determined by RT-PCR, Western blotting, and casein zymography assays. In summary Monascus fermented products exerted a potent effect on tumor growth and activation, suggesting that it may useful serves as a supplementary agent in adjuvant cancer therapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 467.

Effects of Monascus-fermented rice extract on malignant cell-associated neovascularization and intravasation determined using the chicken embryo chorioallantoic membrane model

The traditional Chinese medicine, Hong-Qu, also called red mold rice in the United States and Europe, is used for treating blood stasis, a disorder related to hyperlipidemia and atherosclerosis. In addition to improving metabolic syndrome, extracts from Monascus-fermented rice inhibit the proliferation of various cancer cells in vitro and in vivo. The objective was to examine the effect of red mold rice ethanol extract (RMRE) on angiogenesis, invasion, and metastasis during tumor progression. RMRE significantly inhibited the proliferation of SW480 and SW620 human colorectal carcinoma cells in a dose- and time-dependent manner by using the MTT assay. A capillary-like network morphology was observed after the addition of 20 ng/mL vascular endothelial growth factor or SW620 culture-conditional medium, which was not seen after RMRE treatment. Moreover, spontaneous intravasation into Matrigel grafts of SW620 cells from the upper to the lower layers in the chick embryo chorioallantoic membrane (CAM) model was detected by the polymerase chain reaction (PCR) amplification of human Alu genomic DNA from the lower CAMs in the RMRE-untreated group. Neovascularization increased to 75.3% +/- 11.6% by SW620 cells onplant with Matrigel grafts in the CAM model. However, RMRE significantly reduced CAM neovascularization in a dose-dependent manner. Finally, RMRE effectively decreased the activity of matrix metalloproteinase (MMP)-7 as determined by reverse transcription PCR (RT-PCR), Western blotting, and casein zymography assays. In summary, Monascus-fermented products exert a potent effect on tumor growth and activation, suggesting that they may serve as supplementary agents in adjuvant cancer therapy.

A new dimeric phenylpropanoid and cytotoxic norditerpene constituents from Podocarpus nakaii

A new dimeric phenylpropanoid namely podonaka A (1), along with the 13 known compounds including diterpenes (2 and 3), norditerpenes (4 and 5), benzenoids (6-10), steroids (11 and 12), chalcone (13), and megastigmane (14), was isolated from the EtOH extract of Podocarpus nakaii Hayata. The structure of 1 was elucidated on the basis of spectroscopic analysis including 1D and 2D NMR and MS techniques. Biological evaluation showed that norditerpenes, inumakilactone B (4), and podolactone E (5) have potent cytotoxic activities against Daoy, WiDr, KB, and HeLa tumor cell lines. Moreover, low dosage of 5 may induce early apoptosis in KB cells before 12 h.

Triterpenoid saponins from the fruits and galls of Sapindus mukorossi

Six saponins, sapinmusaponin K (1) [hederagenin-3-O-(3-O-acetyl-alpha-L-arabinopyranosyl)-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside], sapinmusaponin L (2) [hederagenin-3-O-(4-O-acetyl-alpha-L-arabinopyranosyl)-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabino-pyranoside], sapinmusaponin M (3) [hederagenin-3-O-(2,3-O-diacetyl-beta-D-xylopyranosyl)-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside], sapinmusaponin N (4) [hederagenin-3-O-(2,4-O-diacetyl-beta-D-xylopyranosyl)-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside], sapinmusaponin O (5) [3,7,20(S)-trihydroxydammar-24-ene-3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside], and sapinmusaponin P (6) [3,7,20(R)-trihydroxydammar-24-ene-3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-d-glucopyranoside], along with seven known saponins (7-13), were isolated from fruits and the galls of Sapindus mukorossi. Their structures were elucidated by 1D and 2D NMR spectroscopic techniques and acid hydrolysis. Biological evaluation indicated that saponins 1-4 and 7-13 showed moderate cytotoxicity against several human tumor cell lines.

The removal and recovery of Cr(VI) by Li/Al layered double hydroxide (LDH)

Hexavalent Cr has been identified as one of the toxic metals commonly present in industrial effluents. Among the treatment techniques developed for removing Cr(VI) from waste waters, sorption is most commonly applied, due to its simplicity and efficiency. However, few adsorbents can be recycled and reused cost-effectively. In this study, the removal and recovery of Cr(VI) from water using Li/Al LDH was investigated. The removal of Cr(VI) by Li/Al LDH was evaluated in a batch mode. The results demonstrated that Cr(VI) adsorption onto Li/Al LDH occurs by replacing the Cl(-) that originally exists in the interlayer of the adsorbent. The degree of Cr(VI) adsorption observed for Li/Al LDH was relatively high and the process occurred rapidly; however, a portion of adsorbed Cr(VI) was gradually desorbed, due to the Li de-intercalation of Li/Al LDH. Lithium de-intercalation from Li/Al LDH with interlayer Cl(-) and interlayer Cr(VI) follows the first order kinetics and has the activation energies of 76.6 and 41.5 kJ mol(-1), respectively. The properties of thermal unstability and the high adsorption capacity of Li/Al LDH may lead to the development of an innovative technique for the removal of Cr(VI) from Cr(VI)-containing wastewater. That is, Li/Al LDH may be used as an effective adsorbent for the adsorption of Cr(VI) in an ambient environment. Following the adsorptive process, the adsorbed Cr(VI) may be released, using heated water to treat the Cr(VI)-containing Li/Al LDH particles. Through this hydrothermal treatment of the used adsorbent, Cr(VI) can be recovered and the solid product (gibbsite) can be recycled for further use.

A common mechanism for perceptual filling-in and motion-induced blindness

Perceptual-filling-in (PFI) and motion-induced-blindness (MIB) are two phenomena of temporary blindness in which, after prolonged viewing, perceptually salient targets repeatedly disappear and reappear, amidst a field of distracters (i.e., non-targets). Past studies have shown that boundary adaptation is important in PFI, and that depth ordering between target and distracter pattern is important in MIB. Here we show that the reverse is also true; that boundary adaptation is important in MIB, and that depth ordering is important in PFI. Results corroborate our earlier conjecture that PFI and MIB are highly related phenomena that share a common underlying mechanism. We argue that this mechanism involves boundary adaptation, but also that the depth effect shows that boundary adaptation can be no more than a sufficient cause of PFI and MIB, and not a necessary one.

Linking motion-induced blindness to perceptual filling-in

"Motion-induced blindness" and "perceptual filing-in" are two phenomena in which perceptually salient stimuli repeatedly disappear and reappear after prolonged viewing. Despite the many similarities between MIB and PFI, two differences suggest that they could be unrelated phenomena: (1) An area surrounded by background stimuli can be perceived to disappear completely in PFI but not in MIB and (2) high contrast stimuli are perceived to disappear less easily in PFI but, remarkably enough, more easily in MIB. In this article we show that the apparent differences between MIB and PFI disappear when eccentricity, contrast, and perceptual grouping are taken into account and that both are most likely caused by the same underlying mechanism.

Predictors of use of highly active antiretroviral therapy (HAART) among persons with AIDS in San Francisco, 1996-1999

Highly active antiretroviral therapy (HAART) has contributed to a decrease in AIDS-related morbidity and mortality. This study used population-based AIDS surveillance data to evaluate the prevalence and predictors of HAART use among persons with AIDS in San Francisco. Use of HAART among persons living with AIDS increased from 41% in 1996 to 72% in 1999. Fourteen percent of persons diagnosed with AIDS between 1996 and 1999 initiated HAART before their AIDS diagnosis. Use of HAART before an AIDS diagnosis increased from 5% in 1996 to 26% in 1999. In the multivariable analysis, African Americans, injection drug users, and those without insurance at the time of AIDS diagnosis were less likely to use HAART before AIDS diagnosis. Delayed initiation of HAART after AIDS was more likely to occur among African Americans, injection drug users, homeless persons, those with public insurance, and those with higher CD4 counts. Although the overall prevalence of HAART use was high, disparity in use of HAART existed by race and risk group, patient's insurance status, and facility of diagnosis. Barriers in use of treatment should be identified so all persons with AIDS can benefit from improved therapies.

Identification of a gamma-tubulin-binding domain in BRCA1

We previously reported (L-C. Hsu and R. L. White, Proc. Natl. Acad. Sci. USA, 95: 12983-12988, 1998) that hypophosphorylated BRCA1 is associated with mitotic centrosomes in vivo, perhaps through its interaction with gamma-tubulin. In vitro evidence presented here indicates that full-length BRCA1 protein generated by in vitro translation interacts with gamma-tubulin. A specific domain of BRCA1 protein, BRCA1 fragment no. 3 (BF3; amino acids 504-803), is both necessary and sufficient to bind gamma-tubulin. BF3 and gamma-tubulin coimmunoprecipitated when coexpressed in cells. In addition, expression of BF3 interfered with the interaction between BRCA1 and gamma-tubulin. Stable transformants of COS-7 cells that overexpressed BF3 showed a reduced growth rate partly because of increased apoptosis. Furthermore, overexpression of BF3 in COS-7 cells results in the accumulation of mitotic cells with multiple centrosomes and abnormal spindles. Okadaic acid, an inhibitor of protein phosphatases types 1 and 2A, induces hyperphosphorylation of BRCA1, a reduction of both BRCA1 and gamma-tubulin associated with mitotic centrosomes, and an accumulation of abnormal spindle formation. Thus, attenuating the interaction between BRCA1 and gamma-tubulin, and their association with mitotic centrosomes, may induce an increase of aneuploid cell population and contribute to tumorigenesis.

Heparin-coated cardiopulmonary bypass circuits: current status

Heparin-coated circuits have been subjected to vigorous testing, both experimentally and clinically, for the past decade. When the functions of heparin are preserved on the surface, the heparinized surface plays multiple roles in attenuating the systemic inflammatory response. These include the ability to attenuate contact activation, coagulation activation, complement activation and, directly or indirectly, platelet and leukocyte activation. The heparinized surface also renders the cardiopulmonary bypass (CPB) circuits hydrophilic and protein resistant and augments lipoprotein binding. The multifunctional nature of the heparinized surface contributes to the overall biocompatibility of the surface. Clinically, heparin-coated circuits become most effective in reducing systemic inflammatory response and in improving morbidity, mortality, and other patient outcome related parameters when material-independent blood activation is controlled or minimized through a global biocompatibility strategy. Techniques involved in the global biocompatibility strategy are readily available and are being effectively and safely practiced at several centers. With the global biocompatibility strategy, outstanding and reproducible results have been routinely achieved with conventional CPB techniques. Alternative revascularization procedures should equal or surpass conventional CPB, using best clinically proven strategies with respect to patient outcome and long-term graft patency.

MR perfusion studies of brain for patients with unilateral carotid stenosis or occlusion: evaluation of maps of "time to peak" and "percentage of baseline at peak"

Maps of "time to peak" (TTP) and "percentage of baseline at peak" (PBP) were compared with maps of conventional brain perfusion parameters, namely, mean transit time (MTT) and relative cerebral blood volume (rCBV). We performed MR perfusion studies in 11 patients. All of them had occlusion or high-grade stenosis of the unilateral carotid artery. Three areas of old infarct, 4 areas of new infarct, and 10 areas of brain without infarct were evaluated specifically. In all these cases, the TTP maps appeared similar to the MTT maps. They showed increases, normal values, or decreases at the same time in all areas evaluated. Most areas of abnormally decreased CBV had increased signal in PBP maps. In conclusion, the TTP map provided the same qualitative information as MTT. PBP seemed correlated inversely to CBV and was less sensitive in demonstrating abnormality.

Impact of protease inhibitors and other antiretroviral treatments on acquired immunodeficiency syndrome survival in San Francisco, California, 1987-1996

The authors assessed temporal trends in acquired immunodeficiency syndrome (AIDS) survival for 15,271 persons in San Francisco, California, diagnosed between 1987 and 1996 with an opportunistic illness included in the 1987 AIDS case definition. Predictors of survival were evaluated for 5,686 persons who were diagnosed between 1993 and 1996 and met the 1993 AIDS case definition. Median survival was 19 months for persons diagnosed between 1987 and 1989, 17 months for persons diagnosed between 1990 and 1992, 15 months for persons diagnosed between 1993 and 1994, and 31 months for persons diagnosed between 1995 and 1996. Decreased mortality was associated with use of antiretroviral therapy without protease inhibitors before AIDS (relative hazard (RH) = 0.88, 95% confidence interval (CI): 0.8, 1.0) and after AIDS (RH = 0.83, 95% CI: 0.7, 0.9) and use of antiretroviral agents with protease inhibitors before AIDS (RH = 0.25, 95% CI: 0.2, 0.3) and after AIDS (RH = 0.36, 95% CI: 0.3, 0.4). Increased mortality was found for persons aged > or = 40 years (RH = 1.43, 95% CI: 1.3, 1.6), persons initially diagnosed with an opportunistic illness (RH = 1.97, 95% CI: 1.8, 2.2), and homosexual injection drug users (RH = 1.33, 95% CI: 1.2, 1.5). Survival after AIDS has increased. Treatment with antiretroviral agents, particularly protease inhibitors, strongly predicts improved survival.

Mouse type-2 retinaldehyde dehydrogenase (RALDH2): genomic organization, tissue-dependent expression, chromosome assignment and comparison to other types

Retinaldehyde dehydrogenase (RALDH) isozymes catalyze the formation of an essential developmental modulator, retinoic acid. We determined the structural organization of mouse type-2 Raldh2 by isolation of overlapping genomic DNA clones from a phage library. The gene consists of 14 exons spanning more than 70 kb of genomic DNA. It was localized to mouse chromosome 6. Northern blot analysis revealed testis-specific expression. The RALDH genes belong to the aldehyde dehydrogenase (ALDH) multi-gene family. Three types of RALDH genes (e.g. human ALDH1/mouse Ahd2/rat RalDH(I), human ALDH11/mouse Raldh2/rat RalDH(II) and human ALDH6) are highly conserved during evolution, sharing about 70% identity at the amino acid level between any two gene types and 90% identity between any two mammalian genes of the same type. Different RALDH types show specific tissue and developmental expression patterns, suggesting (i) a regulatory mechanism of retinoic acid synthesis via different promoters of RALDH genes, and (ii) distinctive biological roles of different isozymes in embryogenesis and organogenesis.

Effect of heparin reversal and fresh platelet transfusion on platelet emboli post-cardiopulmonary bypass in a pig model

Heparin reversal by protamine and fresh platelet transfusion may decrease bleeding complications post-cardiopulmonary bypass (CPB) and may increase the level of organ trapped platelet emboli. Platelet emboli were quantified in two groups of 12 Yorkshire pigs (30-35 kg), where 111indium labeled autologous platelets (INPLT: 850-1,200 microCi) were injected intravenously before and after CPB (BCPB, ACPB), and the platelet emboli level in intact organs and their samples (brain, heart, kidneys, lung, liver, and spleen) was quantified with an ion chamber and a gamma counter, respectively. All pigs were systemically heparinized (ACT > 400 sec). CPB was carried out at 2.5-3.5 L/min at 28 degrees C using a centrifugal pump, an oxygenator (OX:Bentley Univox 1.8 m2), an arterial filter (AF:0.25 m2), and a cardiotomy reservoir (CR: BMR 250) for 90 min. Heparin was reversed with an equivalent dose of protamine. The percent of INPLT dose (ID%, mean +/- SD) in organs of BCPB and ACPB pigs was calculated. The sequence of platelet emboli on a unit weight basis (ID%/g) had the following order: Spleen > Liver > Lung > Kidneys > Heart > Brain. The presence of significantly higher levels of emboli in brain, heart, and kidneys in the ACPB than the BCPB group suggest that platelet transfusion after heparin reversal with protamine may increase the risk of platelet emboli. However, it is an acceptable risk for patients having bleeding complications post-CPB.

Sp1-like proteins function in the transcription of human ferredoxin genes

We characterized a regulatory element located in the -76 to -62 region of the human ferredoxin gene. This region bound to Sp1-like proteins with low affinity, as shown using electrophoretic mobility shift, competition, antibody binding, and Southwestern experiments. The similarity of the regulatory element to Sp1 extends beyond its DNA-binding domain, as cloned Sp1 functioned equally well when fused to a peptide that bound to an irrelevant site. The function of these Sp1-binding sites is mediated through the cAMP-dependent protein kinase (PKA) signaling pathway, because reporter genes downstream of the Sp1-binding sites were not activated in a PKA-deficient cell line. Transfection of the catalytic subunit of PKA restored activated transcription. Similar Sp1-binding sites identified in the CYP11A1 and CYP21 genes also controlled cAMP-dependent transcription of the reporter gene. Our finding of the function of Sp1-like proteins in steroidogenic gene transcription adds one more role Sp1 plays in controlling physiological events.

Chronic daily headache in Chinese elderly: prevalence, risk factors, and biannual follow-up

OBJECTIVE

To investigate the prevalence, risk factors, and prognosis of chronic daily headache (CDH) in a population of elderly Chinese subjects.

METHODS

A community-based survey of registered residents > or =65 years old (n = 2,003) in two townships of Kinmen Island in 1993. A neurologist used a structured questionnaire and clinical interview to make the diagnosis of headache. Subjects who had headaches > or =15 days/month for > or =6 months in the previous year were considered to have CDH. CDH was further classified into chronic tension-type headache (CTTH), CDH with migrainous features (CDH/MF), and other CDH. Person-to-person biannual follow-up of the subjects with CDH was done in June 1995 and August 1997.

RESULTS

A total of 1,533 people (77%) participated in our prevalence study. Sixty subjects (3.9%) fulfilled the criteria for CDH, with a higher prevalence in women (F/M: 5.6%/1.8%, p < 0.001). Of these subjects, 42 (70%) had CTTH, 15 (25%) had CDH/MF, and 3 (5%) had other CDH. Only 23% of those with CDH had consulted physicians for their headaches in the previous year. Multivariate logistic regression revealed the significant risk factors for CDH to be analgesic overuse (OR = 79), a history of migraine (OR = 6.6), and a Geriatric Depression Scale-Short Form score of > or =8 (OR = 2.6). The follow-up results in 1995 and 1997 showed that about two-thirds of the subjects still had CDH. Analgesic overuse (relative risk = 1.6) in 1993 was a significant predictor of persistent CDH at follow-up.

CONCLUSIONS

A total of 3.9% of this elderly population had CDH, with CTTH being the most common subtype. Almost two-thirds of those with CDH had persistent frequent headaches at follow-up. Analgesic overuse was a significant predictor of a poor outcome.

Reduction of Platelet Thrombi and Emboli by L-Arginine during Cardiopulmonary Bypass in a Pig Model

We wanted to test the hypothesis that NO generation by L-arginine (LA) infusion will be beneficial in increasing blood flow to all organs to counteract the process of global ischemia during cardiopulmonary bypass (CPB) and to reduce platelet emboli by platelet inhibition. The effect of LA infusion on NO formation, vasodilation, and reduction of thromboembolic burden in organs and tissues after CPB was quantified with In-111-labeled autologous platelets in two major groups: 180 minutes CPB (CPB) and 90 minutes CPB plus 90 minutes reperfusion (RP). Platelets labeled with In-111 tropolone (650-780 µCi) were administered 24 hours before CPB and LA infusion (bolus, 10 mg/kg and infusion at 2 mg/kg/min, 21 pigs for 180 minutes CPB) in 8 groups of 30 Yorkshire pigs (30-35 kg, 6 pigs; LA 2 mg/kg/min, 3 pigs; sham-thoracotomy control, 6 pigs; unoperated control, 6 pigs). Two groups of 9 pigs (control CPB, 6 pigs; LA 2 mg/kg/min, 3 pigs) underwent 90 minutes of CPB and 90 minutes of reperfusion. All pigs were heparinized (ACT > 400 seconds); CPB was instituted with a roller pump, an oxygenator (OX: Bentley Univox, 1.8 m2), and an arterial filter (AF: 0.25 m2, Bentley) at a blood flow of 2.5-3.5 l/min. Radioactive thrombi in OX and AF and emboli in viscera, brain, and connective tissues were imaged with a gamma camera and were finally measured with an ion chamber and a gamma counter. The percent of injected platelets (mean +/- SD) in the organs and tissues of all pigs was calculated. Cerebral emboli were mapped in 25 regions of both hemispheres of pig brain. Flow cytometry with antibodies to CD61 (GPIIIa) and CD62P (GMP-140:control) of porcine platelets was carried out with blood samples taken before, during, and after CPB. Coronary bypass with LA infusion decreased the amount of adherent thrombi in OX and AF (p < 0.07). The embolic burden in brain and lung also decreased. Regional cerebral mapping of In-111 platelets showed reduced emboli in almost all regions, including the medulla, hip pocampus, and posterior cerebral cortex in both LA-treated groups. Flow cytometry of blood samples demonstrated the shift of equilibria from single platelet to platelet-aggregate-microparticle during CPB and steady-state level after the first 5-10 minutes of initiation of CPB. The L-arginine infusion reduced thrombi and emboli during CPB in the pig model.

Spectral analysis of arterial blood pressure and cerebral blood flow velocity during supine rest and orthostasis

This study evaluates the effect of orthostasis on the low frequency (LF, 0.04 to 0.15 Hz) fluctuations in the blood flow velocity of the middle cerebral artery (MCAFV) in relation to its arterial blood pressure (ABP) equivalent to further define and quantify this relationship in cerebrovascular regulation. Spectral analysis was performed on 22 healthy subjects during supine rest and head-up tilt. The power in the LF range can be used to quantify the LF fluctuations, and four types of LF power data could be obtained for each individual: LF power of supine MCAFV, LF power of supine ABP, LF power of tilt MCAFV, and LF power of tilt ABP. By comparing LF power of MCAFV with LF power of ABP, two power ratios could be generated to describe the flow-pressure relationship during supine rest and head-up tilt, respectively, supine power ratio (LF power of supine MCAFV/ LF power of supine ABP) and tilt power ratio (LF power of tilt MCAFV/ LF power of tilt ABP). In addition, an index for dynamic autoregulation in response to orthostasis can be calculated from these two power ratios (tilt power ratio/supine power ratio). The authors found that this index was dependent on the extent of orthostatic MCAFV changes, and the dependency could be mathematically expressed (r = 0.61, P = .0001), suggesting its involvement in cerebrovascular regulation. Moreover, these data further support the previous observation that the LF fluctuations of MCAFV might result from modulation of its ABP equivalent, and the modulation effect could be quantified as the power ratio (LF power of MCAFV/ LF power of ABP). These observations could be an important step toward further insight into cerebrovascular regulation, which warrants more research in the future.

Transcranial Doppler monitoring with head-upright tilting in patients with syncope

BACKGROUND

The aim of our study was to evaluate the effects of orthostatic stress produced by the head-upright tilt test on human cerebral hemodynamics by transcranial Doppler sonography.

METHODS

We studied 60 subjects who were divided into two groups; one of normal controls (n = 43) and one of patients suffering from syncope (n = 17). A 30-minute head-upright tilt test was conducted on all subjects, and heart rate and blood pressure were monitored by surface electrocardiography and cuff sphygmomanometry, respectively. Cerebral blood flow velocity and cerebral vasoreactivity were continuously monitored using transcranial Doppler sonography.

RESULTS

The maximal decreases in mean blood pressure of controls and patients with syncope were 2.6 +/- 7.8% and 0.5 +/- 7.9% of baseline, respectively. The maximal decreases in mean blood flow velocity in the middle cerebral artery between the two groups reached 19.6 +/- 6.2% and 30.7 +/- 14.1% of baseline, respectively (p < 0.05). The increases in pulsatility index between the two groups were 15.4 +/- 14.3% and 16.9 +/- 21.1% of baseline, respectively.

CONCLUSION

The responses of cerebral blood flow to upright tilting differed significantly between normal controls and patients with syncope, implying that the latter may suffer an impairment of cerebral autoregulation. Further studies are needed to ascertain what clinical implications this finding might have.

A double-blind, placebo-controlled study of tacrine in Chinese patients with Alzheimer's disease

The purpose of the study was to evaluate the efficacy and safety of tacrine over 30 weeks in Chinese patients with probable Alzheimer's disease (AD). A total of 100 patients with mild to moderate AD were recruited and randomly assigned to active or placebo treatment. The active group received 30 mg/day of tacrine for the first 6 weeks, 60 mg/day for the next 6 weeks, 90 mg/day for 6 more weeks and then 120 mg/day for the remaining 12 weeks. Safety evaluations included biweekly determinations of alanine aminotransferase (ALT). The primary outcome measures were Cognitive Abilities Screening Instrument (CASI), Clinical Global Impression of Change (CGIC) by investigator and the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). Secondary outcome measures were Mini-mental State Examination (MMSE), Alzheimer's Deficit Scale (ADS) and CGIC by caregivers. Sixty-eight patients were included in an intent-to-treat analysis (48 active and 20 placebo); 56 patients had evaluable data at week 30 (36 active and 20 placebo). The results of the complete case analysis revealed a significant improvement in the CASI and MMSE scores of the active group in the 18th week (90 mg/day) and the 30th week (120 mg/day) (p < 0.01). In the intent-to-treat analysis, significant improvement of the active group was noted on CASI at week 30 (p = 0.05), but there was no significant difference in the measures of IQCODE, CGIC and ADS. The primary reasons for withdrawal of tacrine-treated patients (39 patients, 52%) were asymptomatic ALT elevation, anorexia and nausea/vomiting. These patients all recovered from the adverse events on discontinuation of treatment. Tacrine produced a statistically significant improvement in the CASI and MMSE in Chinese patients with mild to moderate AD using a lower dose than in western people.

The impact of the 1993 AIDS case definition on the completeness and timeliness of AIDS surveillance

OBJECTIVE

To assess the impact of the 1993 change in the AIDS case definition on the completeness and timeframe of AIDS case reporting in San Francisco.

DESIGN

Retrospective review of records: billing records, list of selected diagnostic codes, radiology logs, ophthalmology clinic records, and patient registries at a selection of hospitals, clinics, and physician offices.

SETTING

Hospitals, public/community health clinics, and physician offices.

MAIN OUTCOME MEASURES

The completeness of reporting and the median reporting delay was calculated for hospitals, clinics, and physician offices.

RESULTS

Reporting was 97% complete. Reporting from physician offices was less complete (75%) than from other facilities. The median reporting delay was 1 month and was shorter for persons who met the 1993 AIDS case definition (1 month) than for persons who met the 1987 case definition (3 months).

CONCLUSIONS

AIDS case reporting in San Francisco is highly complete but less so for persons diagnosed at physician offices. The 1993 AIDS case definition has resulted in more timely reporting. Health departments should consider efforts to improve reporting from private physician offices and should evaluate the use of laboratory-initiated CD4 reporting.

Molecular analysis of two closely related mouse aldehyde dehydrogenase genes: identification of a role for Aldh1, but not Aldh-pb, in the biosynthesis of retinoic acid

Mammalian class I aldehyde dehydrogenase (ALDH1) has been implicated as a retinal dehydrogenase in the biosynthesis of retinoic acid, a modulator of gene expression and cell differentiation. As the first step towards studying the regulation of ALDH1 and its physiological role in the biosynthesis of retinoic acid, mouse ALDH1 cDNA and genomic clones have been characterized. During the cloning process, an additional closely related gene was also isolated and named Aldh-pb, owing to its high amino acid sequence identity (92%) with the rat phenobarbitol-inducible ALDH protein (ALDH-PB). Aldh1 spans about 45 kb in length, whereas Aldh-pb spans about 35 kb. Both genes are composed of 13 exons, and the positions of all the exon/intron boundaries are conserved with those of human ALDH1. The promoter regions of Aldh1 and Aldh-pb demonstrate high sequence similarity with those of human ALDH1 and rat ALDH-PB. Expression of Aldh1 and Aldh-pb is tissue-specific, with mRNAs for both genes being found in the liver, lung and testis, but not in the heart, spleen or muscle. Expression of Aldh-pb, but not Aldh1, was also detected at high levels in the kidney. Aldh1 and Aldh-pb encode proteins of 501 amino acids with 90% positional identity. To examine the relative roles of these two enzymes in retinoic acid synthesis in vivo, Xenopus embryos were injected with mRNAs encoding these enzymes to assay the effect on conversion of endogenous retinal into retinoic acid. Injection of ALDH1, but not ALDH-PB, mRNA stimulated retinoic acid synthesis in Xenopus embryos at the blastula stage. Thus our results indicate that Aldh1 can function in retinoic acid synthesis under physiological conditions, but that the closely related Aldh-pb does not share this property.

Transfer function analysis of cerebral hemodynamics in patients with carotid stenosis

This study evaluates the validity of the transfer function analysis of spontaneous fluctuations of arterial blood pressure (ABP) and blood flow velocity of the middle cerebral artery (MCAFV) as a simple, convenient method to assess human cerebral autoregulation in patients with carotid stenosis. Eighty-three consecutive patients with various degrees of carotid stenosis and 37 healthy controls were enrolled. The carotid stenosis was graded based on the diagnostic criteria of duplex ultrasound. Instantaneous bilateral MCAFV and ABP of all participants were assessed noninvasively using transcranial Doppler sonography and the servocontrolled infrared finger plethysmography, respectively. Spectral analyses of ABP and MCAFV were performed by fast Fourier transform. The fluctuations in ABP as well as in MCAFV were diffracted into three components at specific frequency ranges designated as high-frequency (HF; 0.15 to 0.4 Hz), low-frequency (LF; 0.04 to 0.15 Hz), and very low-frequency (VLF; 0.016 to 0.04 Hz). Cross-spectral analysis was applied to quantify the coherence, transfer phase, and magnitude in individual HF, LF, and VLF components. Transcranial Doppler CO2 vasomotor reactivity was measured with 5% CO2 inhalation. The LF phase angle (r=-0.53, P<0.001); magnitude of VLF (r=-0.29, P=0.002), LF (r=-0.35, P<0.001), and HF (r=-0.47, P<0.001); and CO2 vasomotor reactivity (r=-0.66, P<0.001) were negatively correlated with the severity of stenosis. Patients with unilateral high-grade (greater than 90% stenosis) carotid stenosis demonstrated significant reduction in LF phase angle (P<0.001) and HF magnitude (P=0.018) on the ipsilateral side of the affected vessel compared with their contralateral side. The study also revealed a high sensitivity, specificity, and accuracy using LF phase angle and HF magnitude to detect a high-grade carotid stenosis. A strong correlation existed between the LF phase angle and the CO2 vasomotor reactivity test (r=0.62, P<0.001), and the correlation between the HF magnitude and the CO2 vasomotor reactivity (r=0.44, P<0.001) was statistically significant as well. We conclude that transfer function analysis of spontaneous fluctuations of MCAFV and ABP could be used to identify hemodynamically significant high-grade carotid stenosis with impaired cerebral autoregulation or vasomotor reserve.

Characterization of the consequence of a novel Glu-380 to Asp mutation by expression of functional P450c21 in Escherichia coli

P450c21 catalyzes an important step in steroid synthesis. Its deficiency leads to symptoms of steroid imbalance. To obtain enough P450c21 for structure and function studies, we developed a method to express P450c21 in Escherichia coli. The 5'-region of the human P450c21 cDNA was modified to ensure efficient translation and the C terminus of the protein was extended with four His residues for easy purification. Mutant proteins with substitutions at residues 172 and 281 exhibited decreased enzymatic activities similar to those found in mammalian cells. One new mutation changing Glu-380 to Asp (D380) caused 3-fold reduction in enzymatic activity. The amount of apoprotein production detected by immunoblotting and the affinity of the mutant protein towards substrate as measured by Km were normal. The defect lies in the decreased ability of the apoprotein to bind heme, which was measured by CO difference and substrate-binding spectra. The D380 mutant protein had 3-fold reduction in peak heights in both spectra. This reduced heme binding resulted in 3-fold lower enzymatic activity.