Asian Pacific Journal of Tropical Medicine

98-105

Authors: Moragot Chatatikun, Takeshi Yamauchi, Kenshi Yamasaki, Anchalee Chiabchalard, Setsuya Aiba

Objective: To determine the effect of extracts from Phyllanthus acidus (P. acidus) (L.) Skeels and Rhinacanthus nasutus (R. nasutus) (L.) Kurz leaves on melanogenesis and the underlying mechanism in normal human epidermal melanocytes (NHEM) and a reconstitutive skin model. Methods: NHEM and a reconstitutive skin model were stimulated with ethanol extracts of P. acidus (L.) Skeels and R. nasutus (L.) Kurz leaves. mRNA expression of microphthalmiaassociated transcription factor (MITF), tyrosinase (TYR), tyrosinase-related protein 1 (TYRP1) and dopachrome tautomerase (DCT) were examined by real-time PCR. The melanin content in NHEM was also measured. Moreover, protein levels of tyrosinase were determined using western blot analysis. Results: In NHEM and the reconstitutive skin model, ethanol extracts from P. acidus (at 12.5 and 25.0 μg/mL) and R. nasutus (at 6.25 and 12.50 μg/mL) significantly diminished mRNA expression of MITF, TYR, TYRP1 and DCT in a concentration-dependent manner. P. acidus and R. nasutus extracts also reduced the amount of melanin in α-MSH-stimulated NHEM. Moreover, P. acidus and R. nasutus extracts markedly suppressed tyrosinase at the translational level in the reconstitutive skin model. Conclusions: P. acidus and R. nasutus extracts significantly reduced melanogenesis in NHEM and the reconstitutive skin model, suggesting that P. acidus and R. nasutus extracts can inhibit melanin synthesis through downregulation of MITF, TYR, TYRP1 and DCT. Therefore, the ethanol extracts of P. acidus and R. nasutus contain compounds that have the potential for development as a skin lightening agent for the treatment of hyperpigmentation disorder or melasma.

117-122

Authors: Abdelhakim Bouyahya, Omar Belmehdi, Jamal Abrini, Nadia Dakka, Youssef Bakri

Objective: To determin the chemical compounds of Mentha suaveolens (M. suaveolens) and Pinus halepensis (P. halepensis) essential oils (Eos) and evaluate their antioxidant and antibacterial activities. Methods: The chemical composition of P. halepensis and M. suaveolens EOs was determined by GC-MS analysis. The antioxidant activity was evaluated using DPPH, ABTS and FRAP assays. The antibacterial effect was tested against 6 bacterial strains using the well diffusion method and micro-dilution assay. Results: The major components of P. halepensis EOs were β-caryophyllene (28.04%), myrcene (23.81%) and α-pinene (12.02%). However, piperitenone oxid (56.28%), piperitenone (11.64%) and pulegone (6.16%) were the major components of M. suaveolens EOs. M. suaveolens EOs showed remarkable antioxidant activities compared with P. halepensis EOs, showing antioxidant capacity values of IC50=(64.76±2.24) μg/mL, IC50=(82.73±3.34) μg/mL, and IC50=(93.35±4.45) μg/mL, revealed by DPPH, ABTS and FRAP assays, respectively. However, P. halepensis EOs showed interesting antibacterial effects against all bacterial strains. The most sensible strains to P. halepensis EOs were Staphylococcus aureus [(34.00±0.50) mm], Listeria monocytogenes [(31.00±1.50)] mm and Proteus mirabilis [(29.00±2.25)mm]. Furthermore, the lowest minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were revealed by P. halepensis EOs against Staphylococcus aureus [MIC=MBC=0.125% (v/v)] and Listeria monocytogenes [MIC=MBC=0.25% (v/v)]. Conclusions: P. halepensis and M. suaveolens EOs contain bioactive compounds that could have potential applications against bacterial infections and oxidative stress related diseases as well as for food conservation. However, further investigations are necessary to isolate and investigate the action mechanisms of these bioactive compounds.

130-136

Authors: Molouk Beiromvand, Esmat Panabad, Abdollah Rafiei

Objective: To evaluate the prevalence and risk factors of intestinal parasitic infections in the urban and rural areas of Shushtar County, southwest Iran. Methods: A total of 1 008 fecal samples were analyzed by direct smear examination, formalinether concentration, and Ziehl-Neelsen and trichrome staining; furthermore, PCR was used to distinguish Trichostrongylus and hookworm species based on 28S rRNA gene. Results: Totally, 16.0% cases tested positive, either with a pathogenic or a non-pathogenic parasite. Protozoa were detected in 14.0%, helminths in 1.0%, protozoa and helminth coinfections were detected in 0.3%, and co-infections of two protozoa were detected in 0.7% of cases. The most common protozoa and helminths were Giardia duodenalis (7.7%) and Trichostrongylus spp. (0.5%), respectively. Among five microscopy Trichostrongylus positive cases, Trichostrongylus culbriformis was successfully identified in three isolates by sequencing. In the rural areas, the prevalence of parasitic infection was higher (9.8%) than that in the urban areas (6.2%). A significant association was found between educational level, type of drinking water, animals contact, hand-washing, and clinical symptoms. Conclusions: This study indicates that intestinal parasitic infections remain as a public health priority in Shushtar County. It seems that drinking water and environmental sanitation are the main risk factors of parasitic infections in rural areas.

142-146

Authors: Fabrizio Bertelloni, Errica Lunardo, Guido Rocchigiani, Renato Ceccherelli, Valentina Viginia Ebani

Objective: To investigate the potential role of wild birds as fecal spreaders of enteropathogenic, enterohemorrhagic and Shiga-toxins producing Escherichia coli (E. coli ), enteropathogenic E. coli, enterohemorrhagic E. coli and Shiga toxin-producing E. coli strains. Methods: Fecal samples collected from 121 wild birds of different orders and species were submitted to molecular analyses. In particular, eaeA encoding intimin, hlyA encoding for hemolysin, stx1 and stx2 genes encoding Shiga-toxins 1 and 2, respectively, were investigated. Results: Overall, 21(17.35%) fecal samples resulted positive for at least one of the investigated genes. In detail, 12(9.91%) samples were positive for eaeA, 10(8.26%) for stx1, 4(3.31%) for hylA and 1(0.83%) for stx2. An owl (Athene noctua) positive for the four investigated genes suggesting that it harbored a STEC strain. However, virulence genes characterizing EPEC, and EHEC strains were mainly found among seagulls, waterfowl and feral pigeons. Conclusions: Seagulls, waterfowl and feral pigeons, which frequently reach and contaminate rural, urban and peri-urban areas with their droppings, may be important sources of E. coli infection for other animals and humans.