Tropical biomedicine最新文献

Post-COVID-19 conditions encompass a wide range of health problems, including enteritis, but their association with parasitic infections has not yet been investigated. This study analyzed gastrointestinal symptoms, medical histories, fecal Cryptosporidium oocysts, and the history of COVID-19 infection in patients who attended the Faculty of Medicine, Cairo University, from January to July 2021. Fecal biomarkers, including H. pylori, occult blood, fecal calprotectin (FCAL), and TNF-a, were measured, and Cryptosporidium spp. genotypes were molecularly characterized among post-COVID-19 patients using RFLP. Preliminary results from 210 post-COVID-19 patients revealed that group 1 (Cryptosporidiumpositive) (n = 49) and group 2 (Cryptosporidium-negative) (n = 161) showed no significant difference in the prevalence rate of diabetes mellitus (DM). While group 2 was linked to diarrhea, only infections with Cryptosporidium post-COVID-19 were related to chronic diarrhea, vomiting, and weight loss. A total of 220 healthy subjects served as negative controls. Administering azithromycin, hydroxychloroquine, and ivermectin was significantly related to an increased risk of Cryptosporidium infection in group 1, whereas only azithromycin was more frequently recorded in group 2. Antioxidant supplementation insignificantly affected the incidence of cryptosporidiosis. Cryptosporidiosis with a history of COVID-19 was linked to H. pylori infections, increased inflammatory biomarkers (FCAL and TNF-a), and occult blood when compared with group 2. Cryptosporidium genotype 1 was the most commonly occurring subset in individuals with post-COVID-19. The findings demonstrated that aggravating gastrointestinal manifestations, increased fecal biomarkers and anti-COVID-19 therapeutic interventions are significantly related to the existence of Cryptosporidium oocysts in patients with post-COVID-19, indicating the predominance of.

Simulium takahasii (Rubtsov), which was originally described from Japan, and recorded from Korea and China, is the first among the 19 species of the subgenus Wilhelmia Enderlein recorded from East Asia. It is striking in mating, blood-feeding and ovipositing in captivity and in experimentally transmitting Dirofilaria immitis (Leidy) and Brugia pahangi (Buckley & Edeson), and it is a severe biter of cattle and horses, rarely of humans. Nevertheless, updated information about its morphological characteristics was lacking, making comparisons with related species described from China difficult, since species of the subgenus Wilhelmia are almost indistinguishable from one another, in particular, in their female terminalia, male genitalia and most of larval features. In this study, as many morphological characteristics as possible of S. takahasii based on specimens from Japan are redescribed. New information about many features of this species including the length of the female sensory vesicle against the third palpal segment, number of male upper-eye (large) facets, arrangement of the eight pupal gill filaments, presence or absence of tiny dark setae on the dorsum of the larval abdomen and the number of rows and hooklets of the larval posterior circlet will be useful in evaluating the species status of several Wilhelmia species in China including the species regarded as S. takahasii.

Culicoides Latreille biting midges are important blood feeding insects. Many species are pests and vectors of the disease causing agents including viruses, protozoa and filarial nematodes which can be transmitted to humans and other animals. However, knowledge of the role of Culicoides as vectors of filarial nematodes is limited, particular in Thailand, where at least 100 species of the genus Culicoides have been reported. In this study, a molecular approach using the 12S rRNA gene sequence was used to detecting the filarial nematode in four common biting midge species, C. actoni Smith, C. oxystoma Kieffer, C. peregrinus Kieffer and C. mahasarakhamense Pramual, Jomkumsing, Piraonapicha & Jumpato in animal shelters from northeastern Thailand. A total of 1,721 specimens were used for molecular screening. An unidentified Onchocercidae sp. was detected in a specimen of C. mahasarakhamense collected from Maha Sarakham province. This filarial species shows 93% sequence similarity with an unidentified Onchocercidae sp. isolated from Culex mosquitoes. Phylogenetic analyses revealed that Onchocercidae sp. from C. mahasarakhamense formed a clade with strong bootstrap support (100%) with filarial species detected in birds. Thus, it is very likely that the Onchocercidae sp. found in this study employes birds as vertebrate hosts which agrees with feeding behavior of C. mahasarakhamense which is known to feed on chicken. Further study is requiring to examine whether this biting midge species is a competent vector of this Onchocercidae sp.

Black soldier fly (Hermetia illucens (Linnaeus, 1758)) larvae inhibit oviposition of house fly (Musca domestica Linnaeus, 1758) by releasing a semiochemical, although in some situations, inhibition is only partial. We hypothesized that there is a certain period in the life cycle of black soldier fly when it can cause antibiosis of the house fly. Choice and non-choice tests were used to separately examine the effectiveness of each developmental stage of black soldier fly (egg, larval (phase I, II, and III), prepupal and pupal stages) and crude extract of larvae on house fly oviposition. Tests using each developmental stage were compared with controls lacking black soldier fly. The effects of black soldier fly on the number of newly hatched house fly larvae were evaluated and there was a significant difference between the test and control in the number of eggs laid by house fly for all phases of the black soldier fly larval stage. Strong inhibition was found in some black soldier fly larval phases. Significant differences in the numbers of house fly eggs oviposited in food containers treated with crude extract were found when compared with a control, confirming that chemicals from black soldier fly larvae resulted in inhibition of oviposition of house fly. The results from experiment also indicated that chemicals from black soldier larvae influenced the number of house fly larvae newly hatched from eggs.

Peptide therapeutics are found to be an emerging and attractive class of treatment due to their highly specific and safe nature. Hence twenty plant peptides were subjected to screening by molecular docking against the envelope protein of the dengue virus using Clus Pro, Patch Dock, and HADDOCK servers. Physicochemical parameters, allergenicity, and toxicity profile of the plant peptides were estimated by Protparam analysis, AllergenFP, and ToxinPred web servers. Six potential compounds namely Ginkbilobin, Cycloviolin-D, Circulin-B, Circulin-A, Cycloviolacin-013, and Circulin-C showed the highest binding energy with both nonallergenic and nontoxic properties. They also exhibited desirable half-lives extending to 30 hrs except for Ginkbilobin, which showed the least half-life of 4.4 hours and non-polar activity. The residues of Ala-4 of Ginkbilobin; Arg-30 of Cycloviolin D; Arg-29 of Circulin A and C interacted with the Try 101 of the domain II of Envelope protein, implying the possible inhibition of the insertion process of the trimeric E protein during fusion with the host cells. Thus, the identified plant peptides could serve as potential leads upon further subjection to in vitro studies.

Oriental theileriosis caused by Theileria orientalis is a growing health concern of lactating cows in its endemic areas. Rapid and sensitive diagnostic tests are demand areas for appropriate and effective prophylactic and therapeutic measures. Quantitative polymerase chain reaction (qPCR) is the answer for both detection and quantification of parasites. Present study deals with qPCR for detection of parasitemia level of T. orientalis in apparently healthy and clinically affected cows. Major piroplasm surface protein (MPSP) gene present in T. orientalis was cloned in pUC57 vector and transformed into E. coli Top 10 cells. Single and mixed infections of hemoprotozoa other than T. orientalis, causing anemia were differentiated through blood smear examination and PCR tests. T. orientalis was detected in 108 (63.15%) ill and 48 (26.66%) healthy cows. Piroplasms detected per 1000 red blood cells (RBCs) was 0-1 in the healthy group as compared to 3-22 in those showing clinical signs. Parasitemia in ill cows ranged between 6.9 × 10² and 4.5 × 10³ parasites / µl of blood which was significantly higher (p<0.05) than healthy group (2.6 × 10² - 5.7 × 10² parasites / µl of blood). Phylogenetic study of the isolates showed similarity with Buffeli type that unfolded its pathogenic form in apparently healthy and ill cows.

Entamoeba histolytica (E. histolytica), the causative agent of amoebiasis, is still a global public health problem that cannot be controlled, especially in tropical and subtropical countries. This study was conducted to obtain information about the incidence of Entamoeba histolytica/dispar/ moshkovskii complex infection and the factors that influence it. The prevalence of infection with the Entamoeba histolytica/dispar/moshkovskii complex and the factors that influence it in people living on the smallest and outermost island of Indonesia, Sabang Island, Aceh Province. This study involved 335 respondents aged >= 10 years. Respondents were selected by non-probability sampling technique. Interviews and observations were conducted to identify risk factors. The Entamoeba histolytica/dispar/ moshkovskii complex was identified by direct examination, concentration, and Whitley's trichrome staining techniques. A Chi-Square test was performed to analyze the correlation of risk factors with the incidence of infection. The prevalence of infection with the Entamoeba histolytica/dispar/ moshkovskii complex in the people of Sabang Island was 26.6% (89/335). Source and adequacy of clean water correlated with the incidence of Entamoeba histolytica/dispar/moshkovskii complex infection. Demographic variables are not correlated with the incidence of infection. However, the group of women aged > 61 years, unemployed, unmarried, and earning less than the regional minimum wage tend to be more likely to be found with Entamoeba histolytica/dispar/moshkovskii complex infections. Thus it can be concluded that the prevalence of infection with the Entamoeba histolytica/dispar/moshkovskii complex on Sabang Island is in the high category. The prevalence of E. histolytica as the causative agent of amoebiasis cannot be explained with certainty because the two identical non-pathogenic Entamoeba species cannot be distinguished by microscopic identification. Sources and adequacy of clean water correlate with the incidence of Entamoeba histolytica/dispar/moshkovskii complex infection in the people of Sabang Island.

Vibrio cholerae is a gram-negative bacterium synonymous with its namesake disease, cholera. Thus, gastrointestinal symptoms are the norm and V. cholerae is very rarely associated with skin and soft tissue infections. We describe a case of a 63-year-old Chinese woman with multiple medical comorbidities on corticosteroid therapy who developed fever and a painful swelling on her left leg after being pricked by a branch while gardening. There was no abdominal pain, vomiting or diarrhea. A diagnosis of bullous cellulitis was made clinically, and blood was sent for bacteriological culture. A beta-hemolytic commashaped gram-negative bacillus was isolated from the blood. It was also oxidase-positive and produced an acid/alkaline (A/K) reaction on triple sugar iron agar. It was identified biochemically as Vibrio cholerae. After additional testing, it was found to be of the O1 serogroup and Ogawa serotype. The infection resolved following a 10-day course of high-dose co-trimoxazole therapy.

Leishmaniasis is an infectious disease with various clinical manifestations. We studied the therapeutic effects of Elettaria cardamomum essential oil (ECEO) against Leishmania major infection. In vitro effects of ECEO against L. major were examined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and macrophage assays. Nitric oxide (NO) production, infection inhibition in macrophages, and the apoptotic activity of ECEO in treated parasites were also measured. By calculating the 50% cytotoxic concentrations (CC₅₀), we studied the cytotoxicity effects of ECEO on human macrophage cells (THP-1). The efficacy of ECEO for improving cutaneous leishmaniasis (CL) lesions in mice (BALB/c) was determined by evaluating the size of lesions and the number of amastigotes before and after four weeks of treatment. The effects of ECEO on liver and kidney function in the tested mice were also evaluated. ECEO dose-dependently (p<0.001) inhibited the viability and the mean number of promastigotes and amastigote forms of L. tropica. Four weeks of treatment with ECEO at the doses of 2.5 and 5 mg/kg/ day significantly (p<0.001) improved the CL lesions and reduced the number of parasites in the infected mice. ECEO significantly increased NO production, apoptosis induction, and infection rate in parasites. The CC₅₀ value for ECEO and MA was 303.4 µg/mL and 835.2 µg/mL, respectively. In the mice receiving ECEO at the doses of 2.5 and 5 mg/kg/day for 28 days, no significant change was reported between the serum level of liver enzymes and kidney factors when compared with the control group. ECEO displayed promising efficacy in parasite reduction in vitro and in the animal model. ECEO can thus be used as an alternative medicine to treat CL.

We have previously isolated a novel avian Orthobunyavirus, Kedah Fatal Kidney Syndrome (KFKS) virus from a broiler farm in Kedah, Malaysia in 2020 with a severe kidney lesion in chickens. The virus was designated as KFKS2_CS virus. Sequence analysis of partial nucleocapsid (N) and nonstructural (NSs) sequence of this virus showed the highest sequence identity with previous KFKS1 from Malaysia (100%) and 97% with a zoonotic Umbre (UMB) virus, which was reported to cause encephalitis in immunocompromised humans in India. Phylogenetic analysis revealed that this virus was clustered together with previous KFKS1 virus from Malaysia, UMB and Cristoli viruses. This study aimed to assess the zoonotic potential of this KFKS2_CS virus in vitro by determining its ability to inhibit the production of interferon (IFN) in human glioblastoma multiforme (GBM) brain cells using reverse-transcriptase polymerase reaction (RT-PCR). This virus blocked the production of interferon-a in this human brain cells. In conclusion, this KFKS2_CS virus may have a zoonotic potential and become a public health concern in the future.