Ommatidia of blow fly, house fly, and flesh fly: implication of their vision efficiency

This work aims to elucidate the number of ommatidia or facets (the outwardly visible units of each ommatidium) for compound eyes in blow flies [Chrysomya megacephala (F.), Chrysomya rufifacies (Macquart), Chrysomya nigripes (Aubertin), Lucilia cuprina (Wiedemann)], house flies (Musca domestica L.), and flesh flies (Liosarcophaga dux Thomson) by manual counts of the corneal spreads. The head of the fly in each species was soaked in 20% potassium hydroxide solution at room temperature for 7 days, and the clear compound eye was dissected into six small parts, each of which was placed onto a slide and flattened using a coverslip. Images of each part were obtained using a microscope connected to a computer. The printed images of each part were magnified, and the total number of ommatidia per eye was manually counted. For males, the mean number of ommatidia was statistically different among all flies examined: L. dux (6,032) > C. rufifacies (5,356) > C. nigripes (4,798) > C. megacephala (4,376) > L. cuprina (3,665) > M. domestica (3,484). Likewise, the mean number of facets in females was statistically different: L. dux (6,086) > C. megacephala (5,641) > C. rufifacies (5,208) > C. nigripes (4,774) > L. cuprina (3,608) > M. domestica (3433). Scanning electron microscopy analysis of adult flies revealed the sexual dimorphism in the compound eye. Male C. megacephala had large ommatidia in the upper two thirds part and small ommatidia in the lower one third part, whereas only small ommatidia were detected in females. Dense postulate appearance was detected in the external surface of the corneal lens of the ommatidia of C. megacephala, C. rufifacies, and C. nigripes, while a mix of dense postulate appearance and variable groove array length was detected in L. cuprina and M. domestica. The probable functions of ommatidia are discussed with reference to other literature. This work has been presented at the 21st Pacific Science Congress held in Okinawa, Japan, in 12–18 June, 2007.     

Human-induced pluripotent stem cells form functional neurons and improve recovery after grafting in stroke-damaged brain

Reprogramming of adult human somatic cells to induced pluripotent stem cells (iPSCs) is a novel approach to produce patient-specific cells for autologous transplantation. Whether such cells survive long-term, differentiate to functional neurons, and induce recovery in the stroke-injured brain are unclear. We have transplanted long-term self-renewing neuroepithelial-like stem cells, generated from adult human fibroblast-derived iPSCs, into the stroke-damaged mouse and rat striatum or cortex. Recovery of forepaw movements was observed already at 1 week after transplantation. Improvement was most likely not due to neuronal replacement but was associated with increased vascular endothelial growth factor levels, probably enhancing endogenous plasticity. Transplanted cells stopped proliferating, could survive without forming tumors for at least 4 months, and differentiated to morphologically mature neurons of different subtypes. Neurons in intrastriatal grafts sent axonal projections to the globus pallidus. Grafted cells exhibited electrophysiological properties of mature neurons and received synaptic input from host neurons. Our study provides the first evidence that transplantation of human iPSC-derived cells is a safe and efficient approach to promote recovery after stroke and can be used to supply the injured brain with new neurons for replacement.     

Synthesis and structure-activity relationship of 2-thiopyrimidine-4-one analogs as antimicrobial and anticancer agents

Considering that some thiopyrimidines were previously reported as potential therapeutics, the present study achieved novel analogs of bioactive 2-substituted thiopyrimidines-4-(3H)-ones via base catalyzed alkylation reaction of 2-thiouracil using alkyl and aralkyl bromides. The title compounds were 2-(1-butylthio)pyrimidine-4(3H)-one (5a), 2-(2-butylthio)pyrimidine-4(3H)-one (5b), 2-(cyclohexylmethylthio)pyrimidine-4(3H)-one (5c), 2-(benzylthio)pyrimidine-4(3H)-one (5d) and 2-(1-adamantylthio)pyrimidine-4(3H)-one (5e). Bioactivity tests revealed that thiopyrimidines 5a, 5c, 5d and 5e exhibited antimicrobial activity. The thiopyrimidine-4-one (5c) showed complete inhibition against Streptococcus pyogenes and Branhamella catarrhalis as well as antifungal action against Candida albicans. Significantly, the 1-adamantylthiopyrimidine (5e) was shown to be the most potent cytotoxic compound against multidrug-resistant small cell lung cancer (H69AR). Their structure-activity relationships were discussed.     

Incidence of HIV-1 infection and effects of clinic-based counseling on HIV preventive behaviors among married women in northern Thailand

To determine the incidence of and risk factors for HIV-1 infection among married women in northern Thailand, we enrolled 779 seronegative women from family planning clinics and a postpartum ward in Chiang Rai, Thailand, from 1998 through 1999. Women were tested for HIV antibodies at 6 and 12 months after enrollment. They received HIV prevention counseling at enrollment and at each follow-up visit. Counseling covered partner communication, partner HIV testing, and condom use by steady partners. Effects of counseling were measured using standardized questionnaires. Follow-up rates were 94% at 6 months and 92% at 12 months. Only 1 woman seroconverted during the follow-up period, yielding an overall HIV incidence of 0.14 per 100 person-years. After receiving counseling, women reported significantly increased communication with husbands concerning HIV risk, HIV testing, and condom use during the first 6 months after enrollment; communication remained high for 6 to 12 months. Women reported a modest increase in HIV testing and consistent condom use by husbands. The risk for HIV transmission to women in steady relationships is low in northern Thailand. Although HIV prevention counseling promoted partner communication, its effects on HIV preventive behaviors were limited.     

Radical scavenging and antioxidant activities of isocoumarins and a phthalide from the endophytic fungus Colletotrichum sp

Five known isocoumarins, monocerin (1), derivative 2, and fusarentin derivatives 3-5, and a new phthalide (6) were isolated from the endophytic fungus Colletotrichum sp. 2 selectively exhibited cytotoxic activity toward the HepG2 cell line. Compounds 2 and 4 scavenged 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals (IC(50) values of 23.4 and 16.4 μM, respectively) and inhibited superoxide anion radical formation (IC(50) values of 52.6 and 4.3 μM, respectively). The C-7 hydroxyl group in 2 and 4 might be important for radical scavenging activities. Isocoumarins 1-3 and phthalide 6 showed potent antioxidant activity.     

Depsidones, aromatase inhibitors and radical scavenging agents from the marine-derived fungus Aspergillus unguis CRI282-03

Three new depsidones ( 1, 3, and 4), a new diaryl ether ( 5), and a new natural pyrone ( 9) (synthetically known), together with three known depsidones, nidulin ( 6), nornidulin ( 7), and 2-chlorounguinol ( 8), were isolated from the marine-derived fungus ASPERGILLUS UNGUIS CRI282-03. Aspergillusidone C ( 4) showed the most potent aromatase inhibitory activity with the IC (50) value of 0.74 μM, while depsidones 1, 3, 6- 8 inhibited aromatase with IC (50) values of 1.2-11.2 μM. It was found that the structural feature of depsidones, not their corresponding diaryl ether derivatives (e.g. 5), was important for aromatase inhibitory activity. Aspergillusidones A ( 1) and B ( 3) showed radical scavenging activity in the XXO assay with IC (50) values of 16.0 and < 15.6 μM, respectively. Compounds 1 and 3- 7 were mostly inactive or showed only weak cytotoxic activity against HuCCA-1, HepG2, A549, and MOLT-3 cancer cell lines.     

A randomized, placebo-controlled trial to assess the safety and acceptability of use of carraguard vaginal gel by heterosexual couples in Thailand

OBJECTIVES: To determine the safety and acceptability of use of Carraguard, a carrageenan-derived candidate microbicide gel, during sexual intercourse in women and men. STUDY DESIGN: We conducted a 6-month randomized, placebo-controlled trial among sexually active, couples at relatively lower risk for HIV infection in northern Thailand. METHODS: Women inserted 1 applicator of study gel vaginally every time the couple had sex. Safety was assessed by symptom report and genital examination of both partners and by changes in vaginal flora. Acceptability was assessed by participant interview. RESULTS: Overall, 55 couples were randomized, 28 to Carraguard use and 27 to the methyl-cellulose placebo gel group. Retention and study gel use were similarly high in both study groups; use of gel without condoms was reported in more than 95% of vaginal sex acts. The 2 study groups were similar in the proportions of women and men with symptoms or with genital findings without epithelial disruption, of men with findings with epithelial disruption, and of women with abnormal genital flora, whereas more women in the placebo group had findings with epithelial disruption. Women and men in both groups reported that the gel and applicator were acceptable. CONCLUSIONS: Carraguard can safely be used an average of 2 to 3 times per week during sex and is acceptable to Thai women and men.     

Brain metastases from cholangiocarcinoma: a first case series in Thailand

Background: Brain metastasis from cholangiocarcinoma (CCA) is a rare but fatal event. To the best of ourknowledge, only few cases have been reported. Herein, we report the incident rate and a first case series of brainmetastases from CCA. Methods: Between January 2006 and December 2010 5,164 patients were treated atSrinagarind hospital, Khon Kaen University; of those, 8 patients developed brain metastasis. Here we reviewedclinical data and survival times. Results: The incident rate of brain metastases from CCA was 0.15%. The medianage of the patients was 60 years. Tumor subtypes were intrahepatic in 6 and hilar in 2 patients. All suffered fromsymptoms related to brain metastasis. Three patients were treated with whole-brain radiation therapy (WBRT),one of whom also underwent surgery. The median survival after the diagnosis of brain metastasis was 9.5 weeks(1-28 weeks). The longest survival observed in a patient in RPA class I with two brain lesions and received WBRT.Conclusion: This is a first case series of brain metastases from CCA with the incident rate of 0.15%. It is rareand associated with short survival time.     

Assessing the performance of a methyl methacrylate-based resin cement with self-etching primer for bonding orthodontic brackets

Questions over the usefulness of a self-etching primer with resin adhesive in the bonding of orthodontic brackets remain unsolved. The purpose of this study was to determine the effects of using Multibond, a new methyl methacrylate (MMA)-based resin cement with self-etching primer, on the shear bond strength of orthodontic brackets compared with Superbond C&B, which is a well-known MMA-based resin cement containing phosphoric acid etching. Metal or plastic brackets were bonded to etched or self-etching primed bovine teeth using Superbond C&B or Multibond. The shear bond strengths were measured after immersion in water at 37 degrees C for 24 hours. Data were analyzed by two-way analysis of variance and Scheffe's test. The surface appearances of the teeth after phosphoric acid etching or self-etching priming were observed by field-emission scanning electron microscopy (FE-SEM). Metal brackets bonded with Multibond had a significantly lower shear bond strength than metal brackets bonded with Superbond C&B. No significant differences in shear bond strength were observed between Multibond and Superbond C&B when plastic brackets were bonded to the enamel. The shear bond strength of metal brackets bonded with Multibond was comparable with that of plastic brackets bonded with Superbond C&B. Adhesive remnant index score showed a tendency of more residual resin cement remaining on the teeth when metal brackets were bonded with Multibond. FE-SEM observation revealed less dissolution of the enamel surface resulting from treatment with Multibond self-etching primer as compared with phosphoric acid. Thus, the Multibond system may be a candidate for bonding orthodontic brackets with the advantage of minimizing enamel loss.