Identification and characterization of microsatellite markers from the tropical sea cucumber, Stichopus horrens (Selenka)

Tropical commercial sea cucumber Stichopus horrens is extensively distributed throughout the tropical Indo-Pacific region, and wild stocks have been severely depleted over the past decade. In this study, we used the microsatellite enrichment library of S. horrens to identify and characterize 13 microsatellite loci, including 11 polymorphic loci and 2 monomorphic loci. Among the 11 polymorphic loci, the number of alleles was 3-8. The observed and expected heterozygosity varied from 0.1364 to 0.8966 and from 0.1653 to 0.7551, respectively. Additionally, all 11 polymorphic loci showed moderate and high polymorphism with the polymorphism information content (0.271-0.7311). A total of 9 polymorphic loci were in Hardy-Weinberg equilibrium, except for 2 loci (adjusted P = 0.004545). Linkage disequilibrium was not detected in any pairs of polymorphic loci. The present study will be useful for studying genetic structure, population conservation, and breeding of wild S. horrens; moreover, our results contribute to the phylogeny and evolutionary research of Holothuroidea.

Isolation and characterization of microsatellite loci in Branchiostoma belcheri Gray (Amphioxus)

Branchiostoma belcheri Gray is a second-class, nationally protected protochordate in China. We developed 10 novel polymorphic sites in B. belcheri, which were examined using a population of 30 wild individuals from Xiamen, China. The polymorphism information content ranged between 0.141 and 0.681, and the number of alleles varied from 2 to 5. The expected and observed heterozygosities varied between 0.1528 and 0.6920, and between 0.1429 and 0.5000, respectively. These novel microsatellite markers will facilitate the genetic analysis and protection of wild B. belcheri individuals, and the possible re-stocking of the species in the long-term.

Isolation and characterization of microsatellite markers of sea cucumber Stichopus horrens

Curry fish (Stichopus horrens) is a tropical holothurian species and is widely distributed in the India-West Pacific. In the present study, 9 polymorphic microsatellite loci were isolated and characterized for S. horrens. These loci were tested in 30 individuals from Hainan Island in China. The number of alleles ranged from 2 to 5. The polymorphism information content ranged from 0.348-0.584. The levels of observed and expected heterozygosities varied from 0.1500-0.8000 and from 0.2014-0.5000, respectively. Most loci were in Hardy-Weinberg equilibrium, except HCS1-27 and HCS2-7, after sequential Bonferroni's correction, and no significant linkage disequilibrium was detected for any pairwise combination of loci. These polymorphic microsatellite loci will be useful for studying population structure and conservation strategy design for S. horrens.

Development and characterization of microsatellite markers for molecular genetic diversity in Atrina pectinata

The pen shell, Atrina pectinata, is an economically valuable species that is widely distributed along the coastal waters of temperate and tropical areas, mainly growing in the Indian and Pacific Oceans. Eight novel microsatellite loci from the genome of A. pectinata were developed using fast isolation by amplified fragment length polymorphism of sequence containing repeats. The loci were screened in 30 wild individuals. The results showed that the number of alleles per locus and the polymorphism information content ranged from 2-6 and from 0.233-0.447, respectively. Observed and expected heterozygosities varied from 0.2069-0.7931 and 0.1887-0.5124, respectively. No significant deviations from Hardy-Weinberg equilibrium were detected. These microsatellite loci will be useful for further population studies of genetic diversity, population structure assessment, and conservation of A. pectinata.

Development and characterization of new microsatellite markers of Fenneropenaeus penicillatus

Thirteen new polymorphic microsatellite markers in Fenneropenaeus penicillatus were isolated and characterized. The polymorphism of the thirteen microsatellite markers was tested by 30 individuals from Lianjiang, China. It showed that the number of al-leles per locus ranged from 3 to 6 and the Polymorphism Information Content (PIC) was from 0.324 to 0.706. The observed and expected heterozygosities were 0.3217-0.8023 and 0.1977-0.6783, respectively. Only one loci (LJ-19) deviated significantly from Hardy-Weinberg equilibrium (HWE) (P < 0.00385) after Bonferroni correction, while the other twelve markers were in HWE after Bonferroni correction (P > 0.00385). The thirteen polymorphic microsatellite markers could pro-vide more genetic data for further research on cultivation and recovery of F. penicillatus.

Screening and characterization of novel polymorphic microsatellite markers from sea cucumber Holothuria leucospilota

The sea cucumber Holothuria leucospilota has high me-dicinal value and rich nutritional edible value, and thus is a commercially important aquatic product in China. Microsatellite loci were developed and screened using a fast isolation protocol and amplified fragment length polymorphism of sequences containing repeats. In this study, 16 novel polymorphic microsatellite markers in H. leucospilota were identified, and the relevant genetic variability index was assessed using 30 individu-als from a wild population. The polymorphic information content ranged from 0.183 to 0.668, and the number of alleles per locus varied from 3 to 5. The observed and expected heterozygosities were 0.0370-0.5000 and 0.0776-0.6250, respectively. With the exception of 3 loci (Y1-15, Y11-1, and Y28), the polymorphic loci were in Hardy-Weinberg equilibrium (P > 0.003125). These polymorphic microsatellite loci will contribute to studies of genetic diversity, the research of population structure, and the design of conservation strategies for H. leucospilota.

Isolation and characterization of polymorphic microsatellite loci in the sea cucumber Holothuria scabra

The sea cucumber Holothuria scabra is an endangered species. In this study, nine new polymorphic microsatellite loci were developed and tested in 30 individuals. The number of alleles ranged from 2 to 5, and the observed and expected heterozygosities ranged from 0.1200 to 0.7391 and from 0.2408 to 0.5983, respectively. No loci significantly deviated from the Hardy-Weinberg equilibrium af-ter a Bonferroni correction, and no significant linkage disequilibrium was found between pairs of loci. These polymorphic microsatellite loci will be useful in studying the genetic diversity of H. scabra and its conservation.

Isolation and characterization of novel polymorphic microsatellite loci in Atrina vexillum Born (Pinnidae)

The pen shell, Atrina vexillum Born, is an edible shellfish that is widely consumed in the Asia-Pacific region. In this study, 11 polymorphic microsatellite loci were isolated from A. vexillum, and 30 wild individuals were used to evaluate the degree of polymorphism of these markers. The number of alleles per locus ranged from 3 to 8. The polymorphism information content varied from 0.199 to 0.831. The observed and expected heterozygosities were 0.1000-0.8667 and 0.1244-0.8356, respectively. Two loci deviated significantly from the Hardy-Weinberg equilibrium (HWE) after a Bonferroni correction, while the other nine loci were at HWE. These microsatellite loci will be useful in further studies on population genetic analyses, and will provide important genetic data for the conservation and recovery of A. vexillum.

Isolation of new polymorphic microsatellite markers from the marbled rockfish Sebastiscus marmoratus

The marbled rockfish, Sebastiscus marmoratus, is an important commercially near-shore fish that inhabits the beach rocky bottom from Japan to the South China Sea. Eleven polymorphic microsatellite loci were developed from S. marmoratus and were used to identify polymorphisms in 30 samples from a wild population. The allele locus number ranged from 2 to 7. Polymorphism data content ranged from 0.032 to 0.751. The observed and expected heterozygosity levels were 0.0333-0.9667 and 0.0328-0.7675, respectively. Two loci, Smd1-112 and Smd2-80, deviated from Hardy-Weinberg equilibrium. These polymorphic microsatellite markers will facilitate further studies of genetic diversity and genetic differentiation of S. marmoratus.

Development and characterization of polymorphic microsatellite loci in the sea cucumber Holothuria leucospilota

Holothuria leucospilota is a tropical holothurian species that is widely distributed in the tropical and sub-tropical India-Western Pacific Region. Eight polymorphic microsatellite loci were developed from H. leucospilota by using the protocol fast isolation by amplified fragment length polymorphism of sequences containing repeats and tested in 30 individuals from Hainan Island in China. The number of alleles was 2-6 and polymorphism information content ranged from 0.371-0.694. The levels of expected and observed heterozygosities varied from 0.3913-0.6701 and from 0.1154-0.7000, respectively. No significant linkage disequilibrium was detected for any pairwise combination of loci. Only loci YZHS1-42 deviated from Hardy-Weinberg equilibrium. These polymorphic microsatellite loci may be useful for germplasm conservation of H. leucospilota.

Isolation and characterization of novel microsatellite markers for molecular genetic diversity in Siganus fuscescens

The rabbitfish Siganus fuscescens is an economically valuable species that is widely distributed throughout the estuaries, intertidal, and offshore coasts of the Indo-Pacific and eastern Mediterranean. Ten novel microsatellite loci from the genome of S. fuscescens were developed using the fast isolation protocol with amplified fragment length polymorphism of sequences containing repeats. Polymorphisms in these 10 microsatellite markers were determined from 32 wild individuals. The number of alleles per locus and the polymorphism information content ranged from 2 to 5 and from 0.059 to 0.668, respectively. The observed and expected heterozygosities varied from 0.063 to 0.781 and from 0.062 to 0.731, respectively. Although 1 locus (LZY-X7, P < 0.005) showed significant deviation from the Hardy-Weinberg equilibrium, no deviations were detected in the other 9 loci. These microsatellite loci may be useful for further population genetic studies, conservation studies, population structure assessment, and linkage map construction of S. fuscescens.

Frequency and features of TP53 mutation in 30 Chinese patients with sporadic basal cell carcinoma

BACKGROUND

Basal cell carcinoma (BCC) is a prevalent form of nonmelanoma skin cancer. Although numerous studies in white populations suggest that mutations in the TP53 gene play an important role in the development of BCC, it is not clear whether this is also the case in East Asian populations such as in China.

AIM

To investigate the frequency and the features of TP53 mutation in sporadic BCC in a Chinese population.

METHODS

In total, 30 patients with sporadic BCC, who had previously taken part in a study on PTCH1 mutations, were enrolled. BCC and control cells were obtained by laser-capture microdissection, and DNA was amplified and sequenced for analysis of TP53 mutations.

RESULTS

In the 30 BCC samples, 6 TP53 point mutations were found (frequency of 20%), and 4 of these 6 mutations had ultraviolet (UV)-specific alterations. Combining these results with those of the previous study on PTCH1 mutations, we found that two patients with had three types of genetic alterations (each had two PTCH1 mutations and one TP53 point mutation). A further two patients each had one PTCH1 mutation and one UV signature TP53 mutation. In addition, the total number of UV-specific mutations of PTCH1 and TP53 accounted for 20% of the total patient group.

CONCLUSIONS

The incidence of TP53 mutation in BCC in our Chinese subjects was lower than that reported for white populations. Many of the patients carried mutations of other genes in addition to of TP53. The majority of TP53 mutations were UV-induced specific alterations. However, the results of the two studies on TP53 and PTCH1 indicated that the incidence of UV-specific mutations is much lower in Chinese than in white populations.

Comparable efficacy and safety of 8 weeks treatment with agomelatine 25-50mg or fluoxetine 20-40mg in Asian out-patients with major depressive disorder

OBJECTIVE

This randomized, double-blind study evaluates the efficacy and tolerability of agomelatine, using fluoxetine as an active comparator, in Asian patients suffering from moderate to severe major depressive disorder (MDD).

METHOD

Patients were randomly assigned to receive either agomelatine (25-50mg/day, n=314) or fluoxetine (20-40mg/day, n=314) during an 8-week treatment period. The main outcome measure was the change in Hamilton Depression Rating Scale 17 items (HAM-D17) scores. Secondary efficacy criteria included scores on Clinical Global Impression Severity of illness (CGI-S) and Improvement of illness (CGI-I), patient sleeping improvement using the self-rating Leeds Sleep Evaluation Questionnaire (LSEQ) and anxiety using the Hamilton Anxiety Rating Scale (HAM-A) scores. Tolerability and safety evaluations were based on emergent adverse events.

RESULTS

Agomelatine and fluoxetine exert a comparable antidepressant efficacy in the Asian population. Mean changes over 8 weeks were clinically relevant and similar in both groups (-14.8±7.3 and -15.0±8.1 on HAM-D17 scale in agomelatine and fluoxetine groups, respectively). The between-group difference reached statistical significance on non-inferiority test (p=0.015). Clinically relevant decreases in CGI-S and CGI-I scores were observed over the treatment period in both groups. The two treatments were equally effective on the symptoms of both anxiety and sleep. The good tolerability profile and safety of both doses of agomelatine was confirmed in the Asian population.

CONCLUSIONS

Agomelatine and fluoxetine are equally effective in the treatment of MDD-associated symptoms in Asian depressed patients.

Identification and characterization of RFRP gene in pigs and its association with reproductive traits

RFamide-related peptide (RFRP) gene is a crucial gene of the hypothalamo-pituitary-gonadal axis and plays an important role in reproduction regulation. This study aimed to clone and characterize the pig RFRP gene. We obtained a 645-bp cDNA of pig RFRP gene comprising a 546-bp open reading frame, which encoded a peptide of 188 amino acids. The pig RFRP coding sequences have the identities of 81, 68.8, and 76.1% with their counterparts in humans, mice, and rats, respectively. Real-time polymerase chain reaction showed that the pig RFRP gene was expressed predominantly in the stomach and testis of males, and large intestine and uterus of females. It was also found to be abundantly expressed in the cerebrum and liver tissues of both male and female pigs. The pig RFRP gene is 4.6 kb long and contains 3 exons and 2 introns. We further identified a total of 25 single nucleotide polymorphisms and 2 insertion/deletion (indel) polymorphisms across the whole RFRP gene, and 9 of them were in the exons. Marker trait association analysis in Yorkshire and Landrace populations showed that g.45859759C>T was significantly associated with the total number born of second parity (TBA2; P < 0.05). In conclusion, the pig RFRP gene was cloned and characterized in this study, and its polymorphism g.45859759C>T showed significant associations with reproductive traits.

Difficulties in organ procurement and transplantation in the aboriginal minority people in Taiwan

BACKGROUND

Aboriginal people (AP) are a minority group in Taiwan. Little information on their perspectives on organ transplantation (OT) is available. Their rights for organ donation (OD) and as OT recipients (OTR) are constrained as a vulnerable population in society. This research sought to explore various Highland Aborigine Tribes beliefs systems and concepts related to OT.

METHODS

We employed a qualitative design on a purposive sample including seven categories of Taiwanese AP. Data collected by face-to-face interviews were evaluated by content analysis.

RESULTS

Seventy-five informants (45 female and 30 males) of 18 to 82 years from seven tribes completed interviews: Bunun (n = 20), Shao (n = 18), Tsou (n = 15), Amis (n = 12), Truku (n = 4), Rukai (n = 3), and Puyuma (n = 3). Of there, 33% had no idea of OT. All informants reported lack of knowledge of OD, organ procurement, and OTR. Eighty percent (45-82 years) had no willingness for OD or OTR; others might consult family members and health professionals (HP) to learn about OT. Seven hindering factors were identified: (1) having no background of OT; (2) limited impressions obtained from television news reports; (3) negative concepts of donating one's organs to others; (4) OT concepts contrast with cultural meanings of death; (5) possibility of being stigmatized; (6) fear of being rejected by others; and (7) HP had never mentioned OT.

CONCLUSIONS

Taiwan APs' perspectives of OT concepts showed the majority to be unfamiliar with the concept and benefits of OT. Future research is necessary to explore the possible avenues to facilitate communications between HP and AP leaders, as well as elders in each AP category in Taiwan.

Merging of the National Cancer Institute-funded cooperative oncology group data with an administrative data source to develop a more effective platform for clinical trial analysis and comparative effectiveness research: a report from the Children's Oncology Group

PURPOSE

The National Cancer Institute-funded cooperative oncology group trials have improved overall survival for children with cancer from 10% to 85% and have set standards of care for adults with malignancies. Despite these successes, cooperative oncology groups currently face substantial challenges. We are working to develop methods to improve the efficiency and effectiveness of these trials. Specifically, we merged data from the Children's Oncology Group (COG) and the Pediatric Health Information Systems (PHIS) to improve toxicity monitoring, to estimate treatment-associated resource utilization and costs, and to address important clinical epidemiology questions.

METHODS

COG and PHIS data on patients enrolled on a phase III COG trial for de novo acute myeloid leukemia at 43 PHIS hospitals were merged using a probabilistic algorithm. Resource utilization summary statistics were then tabulated for the first chemotherapy course based on PHIS data.

RESULTS

Of 416 patients enrolled on the phase III COG trial at PHIS centers, 392 (94%) were successfully matched. Of these, 378 (96%) had inpatient PHIS data available beginning at the date of study enrollment. For these, daily blood product usage and anti-infective exposures were tabulated and standardized costs were described.

CONCLUSIONS

These data demonstrate that patients enrolled in a cooperative group oncology trial can be successfully identified in an administrative data set and that supportive care resource utilization can be described. Further work is required to optimize the merging algorithm, map resource utilization metrics to the National Cancer Institute Common Toxicity Criteria for monitoring toxicity, to perform comparative effectiveness studies, and to estimate the costs associated with protocol therapy.

Unique features of PTCH1 mutation spectrum in Chinese sporadic basal cell carcinoma

BACKGROUND

Alterations of the PTCH1 gene have been found to contribute to both familial and sporadic basal cell carcinoma (BCC), especially in Caucasian patients. Furthermore, the majority of PTCH1 gene mutations in sporadic BCCs in Caucasian patients carry ultraviolet (UV) signatures, suggesting the key role of UV light in BCC development. However, sporadic BCC in non-Caucasian population has a lower incidence, and the pathogenesis remains largely unknown. To date, there has been no mutation analysis on PTCH1 gene in Chinese patients with sporadic BCCs.

OBJECTIVE

To investigate genetic alterations of the PTCH1 gene in Chinese sporadic BCCs.

METHODS

Direct sequencing was used to screen for mutations in PTCH1 in 31 microdissected samples in Chinese sporadic BCCs. In addition, single nucleotide polymorphisms (SNPs) were studied for loss of heterozygosity (LOH).

RESULTS

Nineteen PTCH1 mutations in 17 of the 31 BCCs (54.8%) were identified. SNP analysis revealed LOH of PTCH1 in 10 of 23 BCCs (43.5%). Interestingly, the majority of mutations identified (63.2%) were insertion/deletion, which was different from the results in Caucasian cases whose mutations are predominantly point mutations. Only two (10.5%) of the remaining seven mutations were UV-specific C → T transition or tandem CC → TT transitions. All mutations occurred evenly throughout the entire PTCH1 protein domain without a hot-spot detected.

CONCLUSION

Mutations and LOH in PTCH1 were also highly prevalent in Chinese sporadic BCCs. However, UV light plays a less role in causing these mutations, suggesting other potential mechanisms in the development of sporadic BCC in Chinese patients.

Delayed diagnosis of abdominal mass due to morbid obesity

Obesity has become an increasing problem in developed countries. Obesity is associated with many of the most common causes of morbidity and mortality, including diabetes mellitus, coronary artery diseases, sleep apnoea, and many types of cancers. Not only is morbid obesity associated to a greater extent to the many medical problems related to obesity, but the body habitus of a morbidly obese patient causes limitation to physical examination, radiologic evaluations, and therapeutic interventions that can delay diagnosis and treatment of the patient. We present a case of a morbidly obese patient whose diagnosis of liposarcoma was delayed for over a year as his obesity hindered proper diagnosis and medical treatment.

Preparation and characterization of iridium dioxide-carbon nanotube nanocomposites for supercapacitors

A thin film of novel hierarchical structure, suitable for supercapacitor applications, has been developed through combining conductive multi-wall carbon nanotubes (MWCNTs) and square IrO(2) nanotubes (IrO(2)NT) of nanometer size. Synthesis of this hierarchical structure with open porosity is performed by depositing IrO(2) short tubes densely along the long wires of carbon nanotube on a substrate of stainless steel. A IrO(2) tube of rutile structure grows in the [001] direction, with an opening at its top, surrounded by very thin walls. The IrO(2) addition on the MWCNT template increases the capacitance of the CNT thin film effectively, because of pseudocapacitance of the IrO(2) surface. For this particular composite, featured with two tubular nanostructures, the specific capacitance increases from 15 F g(-1) (MWCNT) to 69 F g(-1) (IrO(2)NT/MWCNT), measured using the galvanostatic discharge experiment. Its property of fast retrieval of the stored charge is assured in the impedance measurement, showing that the internal resistance of the IrO(2)NT/MWCNT nanocomposite electrode is lower than that of the bare MWCNTs.

Cellular dosimetry and microdosimetry for internal electron emitters

Radiobiological descriptions of cellular dosimetry and microdosimetry require both radiation dose and radiation quality. The lineal energy, defined as a ratio of the energy deposition by a particle in the biological target and the mean chord length of this target, is generally adopted to characterise the radiation quality. Most microdosimetry applications assume that the cell nucleus is the target region. Therefore, the lineal energy is obtained for the source (S) to target (T) geometry, T ← S, where S = cell surface, cytoplasm, cell nucleus and T = cell nucleus. The definition of lineal energy is based on the approximation that the particle mean pathlength is equal to target mean chord length. This approximation is valid for crossers of external irradiations. In the case of starters, insiders and stoppers of internal sources, particle pathlengths are always shorter than target chord lengths. Thus, the lineal energy does not reflect the specific energy deposition along particle path. In the present work, the specific energy deposition in a target is calculated using three distance parameters, i.e. target mean chord length, particle mean pathlength in the target and particle individual pathlength in the target. Monte Carlo calculations are performed for electrons of various energies and cells of different sizes. Results are analysed and discussed.

Green fabrication of agar-conjugated Fe3O4 magnetic nanoparticles

Magnetic nanoparticles are of great interest both for fundamental research and emerging applications. In the biomedical field, magnetite (Fe(3)O(4)) has shown promise as a hyperthermia-based tumor therapeutic. However, preparing suitable solubilized magnetite nanoparticles is challenging, primarily due to aggregation and poor biocompatibility. Thus methods for coating Fe(3)O(4) NPs with biocompatible stabilizers are required. We report a new method for preparing Fe(3)O(4) nanoparticles by co-precipitation within the pores of agar gel samples. Permeated agar gels were then dried and ground into a powder, yielding agar-conjugated Fe(3)O(4) nanoparticles. Samples were characterized using XRD, FTIR, TGA, TEM and SQUID. This method for preparing agar-coated Fe(3)O(4) nanoparticles is environmentally friendly, inexpensive and scalable.

Size of the Chloroplast Genome in Codium fragile

Chloroplasts isolated from the siphonous green alga Codium fragile yield circular DNA molecules averaging 27.3 micrometers in length and 56 x 10(6) daltons in molecular size. This chloroplast genome is 25 to 30 percent smaller than any reported. The small size of the Codium chloroplast genome may represent a primitive evolutionary condition in green plants.

Characterization of the DNA of a Nonoccluded Baculovirus, Hz-1V

The DNA of the nonoccluded baculovirus (Hz-1V) obtained from the IMC-Hz-1 cell line was characterized by physicochemical and restriction endonuclease techniques. Hz-1V DNA isolated from purified virus had buoyant densities of 1.58 and 1.54 g/ml in CsCl-ethidium bromide density gradients, which corresponded to supercoiled and to relaxed circular and linear DNA, respectively. Neutral CsCl equilibrium centrifugation indicated that the Hz-1V DNA had a buoyant density of 1.7024 g/ml, which corresponded to a guanine-plus-cytosine (G+C) content of 43%. Thermal denaturation indicated a high G+C domain(s) in the Hz-1V genomic DNA. The domain(s), which included about 11% of the total genomic DNA, exhibited a T(m) of 97 degrees C. The remaining portion (89%) of the DNA had a T(m) of 86.5 degrees C. The T(m)s corresponded to G+C contents of 42 and 67%, respectively. The mean genetic complexity of Hz-1V DNA determined by DNA reassociation kinetic analysis was found to be 152 x 10(6). A possible rapidly reassociating component comprising approximately 13% of the genome was observed. The mean molecular weights from restriction endonuclease digests were 159 x 10(6) for both HindIII and EcoRI. Genomic heterogeneity was found in both the wild-type Hz-1V stock and in two plaque isolates. Of 12 single-plaque isolates, 3 basic restriction endonuclease DNA fragment patterns were observed. The molecular size estimates from electron microscopic contour lengths of uncloned viral DNA ranged from 70 to 158 megadaltons, and the mode was the 130- to 140-megadalton class.

A prospective observational study of attention-deficit hyperactivity disorder in Asia: baseline characteristics of symptom severity and treatment options in a paediatric population

OBJECTIVES

To better understand the burden and management of attention-deficit hyperactivity disorder in East Asia, this subanalysis of the baseline characteristics of a large prospective, observational, nonrandomized study investigating the relationships between symptom severity, treatments, co-morbidities, and health outcomes provides information about the diagnosis of, and treatment patterns for, attention-deficit hyperactivity disorder in this region.

METHODS

Outpatients with attention-deficit hyperactivity disorder symptoms participated in this 12-month study performed in China, Korea, and Taiwan. Patients were grouped according to whether they received conventional treatment or no or other treatment. Attention-deficit hyperactivity disorder symptom severity and co-morbidities were assessed using the Clinical Global Impressions-Attention-deficit Hyperactivity Disorder-Severity scale and Child Symptom Inventory-4: Parent Checklist (categories B to J) / Adolescent Symptom Inventory-4: Parent Checklist (categories L and O), respectively.

RESULTS

A total of 502 patients aged 6 to 18 years were enrolled. Investigators were psychiatrists (69%) and paediatricians (31%), who used the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders (86%), the 10th revision of the International Classification of Diseases (6%), and other attention-deficit hyperactivity disorder diagnostic criteria (8%) for diagnosis. Pharmacotherapy was the most commonly prescribed treatment (n = 251; 50%), and treated patients were older (9.1 vs. 8.2 years; p < 0.001) and more severely ill (Clinical Global Impressions-Attention-deficit Hyperactivity Disorder- Severity scale, 4.6 vs. 4.2; p < 0.001) than those who were not treated. Anxiety and oppositional co-morbidities were commonly reported.

CONCLUSIONS

These data provide an insight into the demographics, diagnosis, and treatment of paediatric patients with attention-deficit hyperactivity disorder in East Asia, and provide a baseline for assessing changes in treatment practices in this population.

Characterization and enhanced field emission properties of IrO2-coated carbon nanotube bundle arrays

Low operating electric field and stable emission current have been achieved in IrO(2) nanocrystal-coated carbon nanotube bundle arrays (CNTBAs). Patterned vertically aligned CNTBAs were synthesized using thermal chemical vapor deposition followed by the deposition of IrO(2) nanocrystals by reactive radio-frequency magnetron sputtering using an Ir target. The structural and spectroscopic properties were characterized by field emission scanning and transmission electron microscopy, and Raman spectroscopy. The current density versus electric field measurements yielded a low turn-on field of 0.7 V microm(-1) at a current density of 0.1 microA cm(-2), a low threshold field of 2.3 V microm(-1) at a current density of 1 mA cm(-2) and a high field enhancement factor of 1 x 10(4) for the IrO(2)-coated CNTBAs. Long-term stability was also demonstrated. The enhancement of field emission characteristics is attributed to the combined effects of the geometrical structure of the IrO(2)-coated CNTBAs, and the natural conducting and enhanced resistance to oxidation properties of IrO(2).

Growth and characterization of V-shaped IrO(2) nanowedges via metal-organic vapor deposition

We report in detail the synthesis and characterization of V-shaped IrO(2) nanowedges (NWs) with an angle of 110° between the two arms. The NWs were grown on top of rutile (R) phase TiO(2) nanorods (NRs) sitting on a sapphire (SA)(100) substrate via metal-organic chemical vapor deposition (MOCVD) by using (C(6)H(7))(C(8)H(12))Ir and titanium-tetraisopropoxide (TTIP, Ti[OCH(CH(3))(2)](4)) as the source reagents. The surface morphology, structural, and spectroscopic properties of the as-deposited nanocrystals (NCs) were characterized by field emission scanning electron microscopy (FESEM), x-ray diffraction (XRD), micro-Raman spectroscopy, transmission electron microscopy (TEM), and selected-area electron diffractometry (SAED). The FESEM images and XRD patterns indicated growth of V-shaped IrO(2)(101) NWs on top of R-TiO(2) NRs. The Raman spectrum showed the nanosize induced redshift and peak broadening of the IrO(2) and rutile phase of TiO(2) signatures with respect to that of the bulk counterparts. TEM and SAED characterizations of IrO(2) NCs showed that the nanowedges were crystalline IrO(2) with a twin plane of (101) and twin direction of [Formula: see text] at the V-junction. The probable mechanisms for the formation of well-aligned IrO(2) NWs are discussed.

Predictive Value of Serum-soluble CD154 in Fulminant Hepatic Failure

The interaction of CD40 with CD154 is a pivotal trigger of immune cascade-inducing acute liver failure, however its clinical significance has not been well studied. The present study aimed to investigate the clinical implications of serum-soluble CD154 (sCD154) levels and the expression of CD40 on monocytes in patients with fulminant hepatic failure (FHF). The results showed that serum sCD154 levels and CD40 expression on monocytes were significantly higher in FHF patients than in acute hepatitis (AH) patients and healthy controls, and were also significantly higher in FHF patients who died, compared with those who survived. We conclude that high serum levels of sCD154 may be linked to fatal outcome in patients with severe liver injury and may be a valuable prognostic marker for survival in patients with FHF.

Growth and characterization of well-aligned densely-packed rutile TiO(2) nanocrystals on sapphire substrates via metal-organic chemical vapor deposition

Well-aligned densely-packed rutile TiO(2) nanocrystals (NCs) have been grown on sapphire (SA) (100) and (012) substrates via metal-organic chemical vapor deposition (MOCVD), using titanium-tetraisopropoxide (TTIP, Ti(OC(3)H(7))(4)) as a source reagent. The surface morphology as well as structural and spectroscopic properties of the as-deposited NCs were characterized using field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), selected-area electron diffractometry (SAED), x-ray diffraction (XRD) and micro-Raman spectroscopy. FESEM micrographs reveal that vertically aligned NCs were grown on SA(100), whereas the NCs on the SA(012) were grown with a tilt angle of ∼33° from the normal to substrates. TEM and SAED measurements showed that the TiO(2) NCs on SA(100) with square cross section have their long axis directed along the [001] direction. The XRD results reveal TiO(2) NCs with either (002) orientation on SA(100) substrate or (101) orientation on SA(012) substrate. A strong substrate effect on the alignment of the growth of TiO(2) NCs has been demonstrated and the probable mechanism for the formation of these NCs has been discussed.

Electrical transport studies of individual IrO(2) nanorods and their nanorod contacts

We have studied the electrical transport properties of individual single-crystalline IrO(2) nanorods prepared by the metal-organic chemical vapour deposition method. With the help of the standard electron-beam lithographic technique, individual nanorods are contacted by Cr/Au submicron electrodes from above. Utilizing two-probe, three-probe and four-probe measurement configurations, not only the intrinsic electrical transport properties of the individual nanorods but also the electronic contact resistances, R(c)(T), have been determined from 300 K down to liquid-helium temperatures. Our measured resistivity behaviour of the nanorods is in close agreement with the current theoretical understanding of this rutile material. On the other hand, we found that the temperature behaviour of the electronic contact resistance obeys the law [Formula: see text] over an extremely wide temperature range, from approximately 100 K down to liquid-helium temperatures. This latter conduction process is ascribed to the hopping of electrons through nanoscale Cr granules and/or an amorphous coating incidentally formed at the interface between the submicron Cr/Au electrode and the nanorod.

An accurate air temperature measurement system based on an envelope pulsed ultrasonic time-of-flight technique

A new microcomputer based air temperature measurement system is presented. An accurate temperature measurement is derived from the measurement of sound velocity by using an ultrasonic time-of-flight (TOF) technique. The study proposes a novel algorithm that combines both amplitude modulation (AM) and phase modulation (PM) to get the TOF measurement. The proposed system uses the AM and PM envelope square waveform (APESW) to reduce the error caused by inertia delay. The APESW ultrasonic driving waveform causes an envelope zero and phase inversion phenomenon in the relative waveform of the receiver. To accurately achieve a TOF measurement, the phase inversion phenomenon was used to sufficiently identify the measurement pulse in the received waveform. Additionally, a counter clock technique was combined to compute the phase shifts of the last incomplete cycle for TOF. The presented system can obtain 0.1% TOF resolution for the period corresponding to the 40 kHz frequency ultrasonic wave. Consequently, with the integration of a humidity compensation algorithm, a highly accurate and high resolution temperature measurement can be achieved using the accurate TOF measurement. Experimental results indicate that the combined standard uncertainty of the temperature measurement is approximately 0.39 degrees C. The main advantages of this system are high resolution measurements, narrow bandwidth requirements, and ease of implementation.

Downregulation of HER2/neu receptor by solamargine enhances anticancer drug-mediated cytotoxicity in breast cancer cells with high-expressing HER2/neu

Overexpression of HER2/neu is associated with drug resistance and poor outcome in breast cancer. Solamargine (SM), a glycoalkaloid purified from the herb Solanum incanum, exhibits HER2/neu gene modulation of HER2/neu high-expressing human breast cancer cell line ZR-75-1. SM downregulation of HER2/neu gene expression was determined by RT-PCR and Southern hybridization. Additionally, the membrane-bound HER2/neu receptor in highly HER2/neu-expressing breast cancer cells was determined by radioimmunoassay, immunocytochemistry, fluorescent immunocytochemistry, and flow cytometry. SM significantly decreased the number of HER2/neu receptors on the cell membrane. Methotrexate (MTX), 5-florouracil (5-Fu), and cisplatin (CDDP) are commonly used for breast carcinoma treatment in clinics; however, patients with HER2/neu overexpression exhibit resistance to these anticancer drugs. Notably, combination of MTX, 5-Fu, and CDDP with SM individually increased the susceptibility of breast cancer cells to these chemotherapeutic agents. Experimental results indicated that downregulation of HER2/neu by SM might be an effective strategy for enhancing drug susceptibility of breast cancer cells expressing high levels of HER2/neu.

Distribution and clinical significance of human papillomavirus subtypes in Shenzhen city, People's Republic of China

This study investigated the subtype distribution of the human papillomavirus (HPV) in the patients with condyloma accuminatum (CA) in Shenzhen city, China, and assessed the relationship between different HPV subtypes and cervical neoplasia. Type-specific prevalence and extent of multiple infections were assessed in the genital tract. CA samples collected from the 352 patients in the departments of dermatology and gynecology from the People's Hospital in Shenzhen during 2004-2006, using MY09/11 PCR and reverse dot blot hybridization for genotyping of 9-20 kinds of HPV subtypes. HPV status was studied in relation to the pathologic findings. HPV type diversity was wide. The low-risk HPV subtype 11 and 6 were the main subtypes, and multiple HPV infection rate was about 37% in HPV-positive samples. High-risk HPV (HR-HPV) types (16, 18, 58, 52, and 33) were the main subtypes in the CA of cervix, especially in the advanced stage cervical intraepithelial neoplasia (cervical intraepithelial neoplasia II(+) or above), multiple HR-HPV infection was found in 87% of HPV-positive samples. We conclude that HPV type 6 and 11 were the main subtypes in patients with CA in Shenzhen region, while HPV type 16 and 18 may be one of the main reasons for malignant changes of cervix, but this study cannot prove the association between multiple HPV infection and severity of cervix lesions.

Optical characterization of a Cd(0.85)Mg(0.15)Se mixed crystal

We present an optical characterization of a Bridgman-grown wurtzite-type Cd(0.85)Mg(0.15)Se mixed crystal in the near-band-edge interband transitions using temperature-dependent contactless electroreflectance (CER) and photoreflectance (PR) in the temperature range 15-400 K. The interband excitonic transitions A and C originating from the band edge and spin-orbital splitting critical points of the sample, respectively, have been observed in the CER/PR spectra. The transition energies and broadening function of the excitonic features are determined via a lineshape fit to the CER/PR spectra. The parameters that describe the temperature dependence of the transition energies of excitons A and C, and the broadening function of exciton A, are evaluated and discussed.

Solamargine induces apoptosis and sensitizes breast cancer cells to cisplatin

Solamargine (SM), a major steroidal alkaloid glycoside, was purified from Solanum incanum plant. SM exhibited the most cytotoxic effect comparing with that of cisplatin (cDDP), methotrexate (MTX), 5-fluorouracil (5-FU), epirubicin (EPI) and cyclophosphamide (CP) against human breast cancer cells. In this study, SM induces apoptosis of the breast cancer cells and the mechanism was characterized. SM up-regulated the expressions of external death receptors, such as tumor necrosis factor receptor I (TNFR-I), Fas receptor (Fas), TNFR-I-associated death domain (TRADD), and Fas-associated death domain (FADD). SM also enhanced the intrinsic ratio of Bax to Bcl-2 by up-regulating Bax and down-regulating Bcl-2 and Bcl-xL expressions. These effects resulted in the release of mitochondrial cytochrome c and activation of caspase-8, -9 and -3 in the cells, indicating that SM triggered extrinsic and intrinsic apoptotic pathways of breast cancer cells. Similar to function way of SM, cDDP causes cancer cell apoptosis though caspase-8/caspase-3 and Bax/cytochrome c pathways, but the resistance to cDDP is correlated with Bcl-2 and Bcl-xL overexpression. However, the overexpression of Bcl-2 and Bcl-xL can be broken through by SM. The combined treatment of SM and cDDP significantly reduced Bcl-2 and Bcl-xL expressions, and enhanced Bax, cytochrome c, caspase-9 and -3 expressions in breast cancer cells. Thus, the combined use of SM and cDDP may be effective in cDDP-resistant breast cancer.

Temperature dependence of surface photovoltage spectroscopy in vertically coupled self-organized InAs/GaAs quantum dots

The surface photovoltage (SPV) spectra of a series of vertically stacked self-organized InAs/GaAs quantum dot (QD)-based laser structures with different spacer layer (SL) thickness were obtained as a function of temperature (77 K </= T </= 300 K). A decrease of the compressive stress for thinner SL samples arising from coherent relaxation enables us to designate the effect of material intermixing as the most probable mechanism of the energetic blueshift of the observed structures. The turnaround characteristic of the temperature-dependent spectral intensity shows that the reduced SPV signal at higher temperature is limited by the carrier scattering and at lower temperature it is governed by the magnitude of built-in electric field and the escape efficiency of the photogenerated carriers. The dot states to be blueshifted by material intermixing are expected to have higher escape rate for carriers out of QDs, thus resulting in lower measurable temperature for the detected SPV signal. The relatively higher signal at low temperature for the 10 nm SL sample provides a direct evidence of the tunneling process of carriers in the stacked QD layers.

Quantification of pre-parturition restlessness in crated sows using ultrasonic measurement

This study presents the non-video, noninvasive, automatic, and on-site monitoring system employing ultrasonic transducers to detect the behavior in sows before, during and after parturition. An ultrasonic transmitting/receiving (T/R) circuit of 40kHz is mounted above a conventional parturition bed. The T/R units use ultrasonic time-of-flight (TOP) ranging technology to measure the height of the confined sows at 8 predetermined locations. It is suggested that the system could be applied to automatic prediction of sow parturition, with automatic notification of remote management personnel so human attendance at the birth could reduce rates of sow and piglet mortality.

Modulation spectroscopy study of the effects of growth interruptions on the interfaces of GaAsSb/GaAs multiple quantum wells

The effects of growth interruption times combined with Sb exposure of GaAsSb/GaAs multiple quantum wells (MQWs) have been investigated by using phototransmittance (PT), contactless electroreflectance (CER) and wavelength modulated surface photovoltage spectroscopy (WMSPS). The features originated from different portions of the samples, including interband transitions of MQWs, interfaces and GaAs, are observed and identified through a detailed comparison of the obtained spectra and theoretical calculation. A red-shift of the interband transitions and a broader lineshape of the fundamental transition are observed from samples grown under Sb exposure compared to the reference sample grown without interruption. The results can be interpreted in terms of both increases in Sb content and mixing of Sb in the GaAs interface layers. An additional feature has been observed below the GaAs region in the samples with Sb treatment. The probable origin of this additional feature is discussed.

Magnetic properties of large area cobalt nanomagnets

We have investigated the magnetization reversal process of cobalt nanomagnetic dot arrays with thickness t in the range from 5 to 90 nm and diameter d in the range from 150 to 250 nm. Large area cobalt nanomagnets were fabricated on Si(100) substrate using deep ultra-violet lithography at 248 nm exposure wavelength. We observed that the magnetic properties of the nanomagnets strongly depend on the thickness and diameter of Co dots due to the effect of the demagnetizing field. The onset of the formation of a magnetization vortex at remanence was found at a phase boundary of thickness and size (e.g., t = 20 nm, d = 250 nm; t = 40 nm, d = 150 nm). Above this boundary, vortex annihilation and nucleation fields markedly varied with the thickness and diameter of the dots. Our experimental results are in good agreement with a simple micromagnetic modelling.

Induction of VX2 carcinoma in rabbit liver: comparison of two inoculation methods

Direct injection of VX2 cell suspension into the liver is simple and widely used. Implantation of a fragment of VX2 tumour into the liver using a surgical technique has also been developed in the last decade. In this study, we compared these two methods in order to find a better modality for establishing VX2 liver mass. Forty rabbits, each weighing 2.8-3.2 kg, were divided into two groups, 20 rabbits in each. In Group 1, a tumour cell suspension containing 1 x 10(6) cells in a volume of 0.1 ml, was injected slowly into the liver parenchyma using a 27-gauge needle during laparotomy. In Group 2, a 1 mm(3) fragment of VX2 carcinoma was inoculated into the sub-capsule of the left anterior lobe of the liver. In Group 1, three rabbits showed no tumour growth and 10 rabbits showed evidence of leakage and tumour seeding outside of the liver. In Group 2, all but one rabbit showed tumour growth and none showed evidence of tumour seeding. The leakage rates were 50% and 0% for Group 1 and Group 2, respectively. Overall, the success inoculation rate was 35% for Group 1 and 95% for Group 2. In conclusion, to create the VX2 liver tumour model in rabbits, direct implantation of VX2 tumour fragment into the liver achieved better results than injecting cell suspension of VX2 tumour into the liver.

Cladistic analysis of iridoviruses based on protein and DNA sequences

Cladograms of iridoviruses were inferred from bootstrap analysis of molecular data sets comprising all published protein and DNA sequences of the major capsid protein, ATPase and DNA polymerase genes of members of the Iridoviridae family Iridovirus. All data sets yielded cladograms supporting the separation of the Iridovirus, Ranavirus and Lymphocystivirus genera, and the cladogram based on data derived from major capsid proteins further divided both the Iridovirus and Ranavirus genera into two groups. Tests of alternative hypotheses of topological constraints were also performed to further investigate relationships between infectious spleen and kidney necrosis virus (ISKNV), an unclassified fish iridovirus for which the complete genome sequence data is available, and other iridoviruses. Cladograms inferred and results of Shimodaira-Hasegawa tests indicated that ISKNV is more closely related to the Ranavirus genus than it is to the other genera of the family.

Correlation of the fatty acid composition and fluid property of the cholesteryl esters in the serum of Nigerian children with sickle cell disease and healthy controls

In a previous study conducted in Nigeria, we found that children with sickle cell disease (SCD) had exceedingly low total serum cholesterol levels (mean=100-102mg/dl). The fact that significant reductions in the levels of certain polyunsaturated fatty acids (PUFA) have been documented in the serum phospholipids of these same SCD subjects led us to inquire as to the fatty acid composition of the cholesteryl esters (CE) in their serum. Lecithin:cholesterol acyl transferase (LCAT), the enzyme in blood that catalyzes the reaction in which tissue cholesterol is acylated prior to its removal from cell membranes, is relatively specific for certain PUFA. CE in blood serum from 43 male and 42 female children with SCD, ages 4-18 years, and equal numbers of age- and gender-matched controls were analyzed for their fatty acid composition. Relative to the non-SCD controls, the CE of the SCD subjects contained 9% less linoleic acid, 16% less arachidonic acid, 40% less alpha-linolenic acid, 50% less eicosapentaenoic acid, and 36% less docosahexaenoic acid, but 15% more palmitic acid and 10% more oleic acid. Overall, the acyl chains of the CE of the SCD subjects were less fluid than those of the controls, as determined by comparison of their mean melting points (MMP) and double bond indices (DBI). MMP and DBI were both estimated from the individual constituent fatty acids comprising the CE acyl chains. The strongest correlations between MMP and fatty acid mole percent were seen with palmitic acid and linoleic acid. These results show that the fatty acid composition of the serum CE of children with SCD is abnormal relative to controls who do not have this hematologic disorder. We speculate that suboptimal fatty acid nutrition in Nigerian children with SCD compromises their ability to remove cholesterol from their tissues due to preference of the LCAT enzyme for PUFA, thereby accounting, in part at least, for the low total serum cholesterol levels one finds in children with SCD.

Expression of the Recombinant Human Interleukin-11 in Pichia pastoris

Full length cDNA of human IL-11 was synthesized by DNA synthesizer. An expression plasmid, pGENYk, containing the recombinant DNA fragment, was linearized and transformed into Pichia pastoris. This recombinant gene was highly expressed in this yeast, and the expression product was purified by a three-step chromatography method. Analysis of the purified recombination protein with SDS-PAGE, Western blot and biological activities showed that the activity of the protein was the same as the Neumega expressed in E.coli.

Fatty acid, amino acid, and trace mineral analyses of five weaning foods from Jos, Nigeria

Five plant-based weaning foods (WF) (Dietrend, Jot-M, Soy, Ang, and Vic-T) locally prepared in Jos, Nigeria were analyzed by gas-liquid chromatography, reverse-phase high performance liquid chromatography, and atomic emission spectrometry with inductively coupled plasma to determine their fatty acid (FA), amino acid, and trace mineral contents, respectively. Results of these direct analyses were compared to expected values derived from food composition tables prepared by the United States Department of Agriculture (USDA). Additionally, results were compared against recommended nutrient values, using breast milk as the standard for FA content and recommended dietary allowances (RDA) for amino acid and mineral contents. The overall nutritional value of the five WF varied considerably and the quantities of particular nutrients determined by direct analysis differed markedly from those estimated using USDA food tables. Comparison of WF fatty acid composition relative to the RDA recommendations and a human milk standard revealed a much higher proportion of both linoleic (35-55 wt%) and alpha-linolenic acids (1%-7 wt%) relative to human milk lipids (11%-12% and 0.8%-0.9% wt, respectively); however, the WF were devoid of arachidonic acid and docosahexaenoic acid. Soy contained the highest amounts of linoleic acid (59.7 mg/g) and alpha-linolenic acid (7.46 mg/g) compared to the other four WF (10.2-41.0 and 0.35-3.18 mg/g, respectively). The linoleic acid/alpha-linolenic acid ratio was within the recommended range (5:1 to 10:1) in only Jot-M (10:1) and Soy (8:1). Dietrend, Vic-T and Ang, contained linoleic/alpha-linolenic ratios of 12:1, 29:1, and 82:1, respectively. The Soy weaning food would provide the most protein (24.3 g/day), based on an estimated daily intake of 65 g of weaning food by a normal six-month-old infant, compared to Jot-M (11.9 g/day), Dietrend (11.7 g/day), Ang (8.07 g/day), and Vic-T (7.26 g/day). The protein RDA for children up to 1 year of age is 13-14 g/day. Comparison of the mineral contents of the WF to the RDAs for various minerals indicated that all five would provide suboptimal amounts of calcium (16 to 250 mg/day) and zinc (1.42 to 3.56 mg/day) compared to respective RDAs of 400 mg/day and 5 mg/day. These data show that the Soy weaning food is an excellent source of linoleic acid and alpha-linolenic acid, as well as being a good source of high quality protein. Jot-M and Dietrend provide useful amounts of the essential FA; however, it is advisable to reevaluate the composition of Ang and Vic-T to find ways to improve the linoleic/alpha-linolenic ratio of each and increase their total protein content. These results document the shortcomings of using published food composition tables based on foods in America when devising weaning foods based on ingredients in another part of the world.

A role for the cytoplasmic polyadenylation element in NMDA receptor-regulated mRNA translation in neurons

The ability of neurons to modify synaptic connections based on activity is essential for information processing and storage in the brain. The induction of long-lasting changes in synaptic strength requires new protein synthesis and is often mediated by NMDA-type glutamate receptors (NMDARs). We used a dark-rearing paradigm to examine mRNA translational regulation in the visual cortex after visual experience-induced synaptic plasticity. In this model system, we demonstrate that visual experience induces the translation of mRNA encoding the alpha-subunit of calcium/calmodulin-dependent kinase II in the visual cortex. Furthermore, this increase in translation is NMDAR dependent. One potential source for newly synthesized proteins is the translational activation of dormant cytoplasmic mRNAs. To examine this possibility, we developed a culture-based assay system to study translational regulation in neurons. Cultured hippocampal neurons were transfected with constructs encoding green fluorescent protein (GFP). At 6 hr after transfection, approximately 35% of the transfected neurons (as determined by in situ hybridization) expressed detectable GFP protein. Glutamate stimulation of the cultures at this time induced an increase in the number of neurons expressing GFP protein that was NMDAR dependent. Importantly, the glutamate-induced increase was only detected when the 3'-untranslated region of the GFP constructs contained intact cytoplasmic polyadenylation elements (CPEs). Together, these findings define a molecular mechanism for activity-dependent synaptic plasticity that is mediated by the NMDA receptor and requires the CPE-dependent translation of an identified mRNA.

Expression of fungal desaturase genes in cultured mammalian cells

Long-chain polyunsaturated fatty acids (LC-PUFA) are important components of cellular structure and function. Most of LC-PUFA are derived from linoleic acid and alpha-linolenic acid. In plants and fungi, these two acids can be synthesized from oleic acid via the action of two enzymes, delta12 and delta15-desaturases. Due to lack of these enzymatic activities and the ability to synthesize these two essential fatty acids, animals must obtain them from the diet. In this report, we demonstrated the expression of a fungal delta12-desaturase gene in mouse L cells incubated in serum-free medium. The results showed a significant increase in the amount of linoleic acid with a concomitant decrease of oleic acid in cellular lipids. Most of the newly formed linoleic acid was incorporated into cellular phospholipids, particularly phosphatidylcholine. The increase of linoleic acid provided the substrate for the endogenous synthesis of (n-6) LC-PUFA, such as eicosadienoic acid (EDA), dihomo-gamma-linoleic acid (DGLA) and arachidonic acid (AA). Prolonged incubation further increased the levels of linoleic acid derived from oleic acid by the action of delta12-desaturase, and the levels of 20:2n-6 produced from linoleic acid by the action of the endogenous elongase. However, prolonged incubation suppressed significantly the formation of DGLA and AA. In a separate study, a fungal delta6-desaturase gene has also been expressed in the mouse L cells incubated in serum-containing medium. The result shows a significant increase in levels of 20:3n-6 and 20:4n-6. These findings demonstrate that through genetic modification, it is possible to (1) generate cell lines which no longer require dietary 'essential' fatty acids and (2) alter the endogenous fatty acid metabolism to enhance the production of LC-PUFA and their derivatives.

Inhibitory effect of conjugated linoleic acid on linoleic acid elongation in transformed yeast with human elongase

Conjugated linoleic acid (CLA; 18:2) refers to a group of positional and geometric isomers derived from linoleic acid (LA; delta9,12-18:2). Using a growing baker's yeast (Saccharomyces cerevisiae) transformed with human elongase gene, we examined the inhibitory effect of CLA at various concentrations (10, 25, 50, and 100 microM) on elongation of LA (25 microM) to eicosadienoic acid (EDA; delta11,14-20:2). Among four available individual CLA isomers, only c9,t11- and t10,c12-isomers inhibited elongation of LA to EDA. The extent of inhibition (ranging from 20 to 60%) was related to the concentration of CLA added to the medium. In the meantime, only these two isomers, when added at 50 microM to the media, were elongated to conjugated FDA (c11,t13- and t12,c14-20:2) by the same recombinant elongase at the rate of 28 and 24%, respectively. The inhibitory effect of CLA on LA elongation is possibly due to competition between CLA isomers and LA for the recombinant elongase. Thus, results from this study and a previous study suggest that the biological effect of CLA is exerted through its inhibitory effect on delta6-desaturation as well as elongation of LA which results in a decrease in long-chain n-6 fatty acids and consequently the eicosanoid synthesis.

Fatty acid composition of the milk lipids of Nepalese women: correlation between fatty acid composition of serum phospholipids and melting point

Milk was collected from 36 Nepalese women, 15 to 32 years of age, in order to investigate relationships between the proportions of intermediate chain-length (C10-C14) fatty acids and critical n-3 and n-6 polyunsaturated fatty acids in the milk lipids they were producing. Serum was also obtained from these lactating women and the fatty acid composition of their serum phospholipid fraction was determined and compared with that of the corresponding milk lipid fraction. Compared to women in technologically advanced parts of the world, the serum phospholipids of the Nepalese women contained nutritionally adequate proportions of linoleic acid (LA) (16.8%), alpha-linolenic acid (ALA) (0.53%), arachidonic acid (AA) (5.69%), and docosahexaenoic acid (DHA) (1.42%). However, although the milk lipids contained adequate proportions of ALA (1.81%), AA (0.43%), and DHA (0.23%), the lipids contained low to moderate percentages of LA (mean, 9.05%). Positive correlations were observed between the proportions of AA (P=0.001, r=0.50) and ALA (P=0.03, r=0.36) in the serum phospholipids and milk lipids of the women. As the proportion of C10-Cl4 fatty acids in the milk lipids increased from 10% to 40%, there was preferential retention of three critical n-3 and n-6 fatty acids (ALA, AA, and DHA) at the expense of two relatively abundant nonessential fatty acids, namely stearic acid and oleic acid. In addition, using fatty acid melting point data and the mol fraction of the 9 most abundant fatty acids in the milk, we estimated the mean melting point (MMP) of the milk lipids of the Nepalese women. The MMPs ranged from 29.3 to 40.5 degrees C (median, 35.5 degrees C). These results indicate that: 1) the levels of AA and ALA in the blood of lactating mothers influence the levels of these fatty acids in the milk they produce; 2) when the mammary gland produces a milk that is rich in C10-Cl4 fatty acids, it somehow regulates triglyceride synthesis in such a way as to ensure that the milk will provide the exclusively breast-fed infant with the amounts of the critical n-3 and n-6 fatty acids it requires for normal growth and development; and 3) the melting point of the milk lipid fraction is determined mainly by the mol % of the intermediate chain-length (C10-C14) fatty acids, oleic acid, linoleic acid, and alpha-linolenic acid.

Inflammatory pseudotumor of the spleen--a case report

A 36-year-old woman had suffered from epigastric fullness for half a year. A splenic mass was found by ultrasonography. She was treated with splenectomy. Inflammatory pseudotumor of the spleen was diagnosed pathologically. This benign tumor in the spleen is extremely rare. To our knowledge, only 67 cases had been reported in the literature. Recognition of this rare entity is important because it may mimic splenic malignancy clinically and radiographically.