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1.
Chemosphere ; 308(Pt 3): 136456, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36150498

ABSTRACT

The coexistence of pharmaceutical compounds and heavy metals in the aquatic environment has resulted in complications in the treatment process and thus, causing uproar among the citizens. The radical-based photocatalysis technology has aroused as an excellent method to eliminate both heavy metal and pharmaceutical compounds in the water. Herein, reported the utilization of the microemulsion technique for the preparation of nanoporous fibrous silica-molybdenum oxide (FSMo) towards simultaneous photocatalytic abatement of hexavalent chromium (Cr(VI)) and tetracycline (TC). The FESEM analysis showed the spherical morphology of the FSMo catalyst with dendrimeric silica fiber. The synthesized FSMo catalyst exhibited narrowed bandgap, high crystallinity, and well Mo element dispersion for enhanced photo-redox of Cr(VI) and TC. Remarkably, simultaneous remediation of the Cr(VI) and TC over FSMo demonstrated superior photocatalytic efficiency, 69% and 75%, respectively, than in the individual system, possibly due to the effective separation of photoinduced charges. The introduction of the Mo element to the silica framework via microemulsion technique demonstrated better dispersion of Mo compared to the incipient wetness impregnation method and thus, yielded higher photocatalytic activity towards simultaneous removal of TC and Cr(VI). Besides, quenching experiments revealed the electrons and holes as the active species that play a dominant role in the simultaneous photo-redox of Cr(VI) and TC. Lastly, the FSMo catalyst demonstrated high stability after four continuous cycles of simultaneous photocatalysis reactions, implying its potential as a suitable material for practical wastewater treatments.


Subject(s)
Environmental Pollutants , Nanoparticles , Catalysis , Chromium/analysis , Light , Molybdenum , Oxides , Pharmaceutical Preparations , Silicon Dioxide , Tetracycline , Wastewater , Water Pollution, Chemical
2.
Environ Res ; 211: 113069, 2022 08.
Article in English | MEDLINE | ID: mdl-35300961

ABSTRACT

A novel Z-scheme titania loaded on fibrous silica ceria (Ti-FSC) was triumphantly fabricated via hydrothermal followed by electrolysis method and evaluated for the visible-light degradation of ciprofloxacin (CIP). Noticeably, Ti-FSC exhibits as an efficient photocatalyst for CIP photodegradation with 95% as followed by titania loaded on fibrous silica (Ti-FS) (68%), Ti-CeO2 (35%), FSC (47%), FS (22%), and CeO2 (17%). The combination of the inherent merits of Ti loaded on FSC is able to realize the crucial role of Ce in harnessing the high dispersion of Ti, which could beneficial for improving the performance proven by XRD, FESEM, TEM and FTIR. Consequently, high dispersion of Ti on FSC has worthwhile towards the interaction of the Si-O-Ti, Ce-O-Ti, and Si-O-Ti, which could enhance the CIP photodegradation by providing more surface defects, narrowing the band gap, improving electron-hole separation and suppressing electron-hole recombination that revealed by XPS, UV-vis/DRS, Nyquist plots and PL studies, respectively. The scavenger study revealed that the controlling species in the system was hydroxyl radical and holes. A potential Z-scheme heterojunction mechanism for Ti-FSC was deduced from the band structure analysis. The possible photodegradation pathway was proposed based on GCMS analysis. Besides, the acceptable reusability, which exceeded 90% of degradation indicated the great application potential of Z-scheme Ti-FSC in wastewater treatment and others application.


Subject(s)
Ciprofloxacin , Silicon Dioxide , Catalysis , Titanium
3.
Environ Res ; 209: 112748, 2022 06.
Article in English | MEDLINE | ID: mdl-35101397

ABSTRACT

With the tremendous development of the economy and industry, the pollution of water is becoming more serious due to the excessive chemical wastes that need to remove thru reduction or oxidation reactions. Simultaneous removal of dual pollutants via photocatalytic redox reaction has been tremendously explored in the last five years due to effective decontamination of pollutants compared to a single pollutants system. In a photocatalysis mechanism, the holes in the valence band can remarkably promote the oxidation of a pollutant. At the same time, photoexcited electrons are also consumed for the reduction reaction. The synergistic between the reduction and oxidation inhibits the recombination of electron-hole pairs extending their lifetime. In this review, the binary pollutants that selectively removed via photocatalysis reduction or oxidation are classified according to heavy metal-organic pollutant (HM/OP), heavy metal-heavy metal (HM/HM) and organic-organic pollutants (OP/OP). The intrinsic between the pollutants was explained in three different mechanisms including inhibition of electron-hole recombination, ligand to metal charge transfer and electrostatic attraction. Several strategies for the enhancement of this treatment method which are designation of catalysts, pH of mixed pollutants and addition of additive were discussed. This review offers a recent perspective on the development of photocatalysis system for industrial applications.


Subject(s)
Environmental Pollutants , Metals, Heavy , Water Pollutants, Chemical , Water Purification , Wastewater , Water Pollutants, Chemical/analysis , Water Purification/methods
4.
Osteoporos Int ; 33(6): 1275-1284, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35091788

ABSTRACT

The baseline sagittal vertical axis (SVA) and pelvic tilt (PT) are independent risk factors of osteoporosis-related fractures in women with osteoporosis. We clarified the SVA and PT to predict the incidence of osteoporosis-related fractures. PURPOSE: Sagittal alignment with osteoporosis women deteriorates with advancing age and sagittal alignment may indicate osteoporosis-related fractures in the future. However, whether the sagittal alignment predicts future osteoporosis-related fracture in patients with osteoporosis has not been clarified. We aimed to investigate the association between sagittal alignment and future osteoporosis-related fractures. METHODS: This was a retrospective cohort study. Of the 313 participants (mean follow-up period, 2.9 years), 236 were included in the analysis. At baseline, we measured bone mineral density (BMD) of the lumbar spine and the femoral neck, sagittal vertical axis (SVA), thoracic kyphosis, pelvic incidence minus lumbar lordosis, sacral slope, pelvic tilt (PT), geriatric locomotive function scale (GLFS), two-step value, and stand-up test. The information on medications and the duration of treatment were reviewed from the medical records. Additionally, participants reported their history of falls at baseline. Multiple logistic regression analysis was used to determine the association of future osteoporosis-related fracture, and adjusted Odds ratios (OR) and 95% confidence interval (CI) were calculated with all predictors as covariates. All continuous variables were calculated using standardized OR (sOR). RESULTS: Osteoporosis-related fractures occurred in 33 of 313 participants (10.5%). Multiple logistic regression analysis showed that a history of falls (OR =4.092, 95% CI: 1.029-16.265, p =0.045), SVA (sOR =4.228, 95% CI: 2.118-8.439, p <0.001), and PT (sOR =2.497, 95% CI: 1.087-5.733, p =0.031) were independent risk factors for future osteoporosis-related fractures. CONCLUSIONS: This study revealed the SVA and PT to predict osteoporosis-related fractures. TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION: UMIN000036516 (April 1, 2019).


Subject(s)
Kyphosis , Lordosis , Osteoporosis , Osteoporotic Fractures , Aged , Female , Humans , Kyphosis/etiology , Lumbar Vertebrae/diagnostic imaging , Osteoporosis/complications , Osteoporosis/epidemiology , Osteoporotic Fractures/complications , Osteoporotic Fractures/etiology , Outpatients , Retrospective Studies
5.
Chemosphere ; 286(Pt 1): 131651, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34346345

ABSTRACT

Nanostructured photocatalysts commonly offered opportunities to solve issues scrutinized with the environmental challenges caused by steep population growth and rapid urbanization. This photocatalyst is a controllable characteristic, which can provide humans with a clean and sustainable ecosystem. Over the last decades, one of the current thriving research focuses on visible-light-driven CeO2-based photocatalysts due to their superior characteristics, including unique fluorite-type structure, rigid framework, and facile reducing oxidizing properties of cerium's tetravalent (Ce4+) and trivalent (Ce3+) valence states. Notwithstanding, owing to its inherent wide energy gap, the solar energy utilization efficiency is low, which limits its application in wastewater treatment. Numerous modifications of CeO2 have been employed to enhance photodegradation performances, such as metals and non-metals doping, adding support materials, and coupling with another semiconductor. Besides, all these doping will form a different heterojunction and show a different way of electron-hole migration. Compared to conventional heterojunction, advanced heterojunction types such as p-n heterojunction, Z-scheme, Schottky junction, and surface plasmon resonance effect exhibit superior performance for degradation owing to their excellent charge carrier separation, and the reaction occurs at a relatively higher redox potential. This review attends to providing deep insights on heterojunction mechanisms and the latest progress on photodegradation of various contaminants in wastewater using CeO2-based photocatalysts. Hence, making the CeO2 photocatalyst more foresee and promising to further development and research.


Subject(s)
Environmental Pollutants , Water Purification , Catalysis , Ecosystem , Humans , Photolysis
6.
Environ Pollut ; 285: 117490, 2021 Sep 15.
Article in English | MEDLINE | ID: mdl-34091265

ABSTRACT

The co-existence of heavy metals and organic compounds including Cr(VI) and p-cresol (pC) in water environment becoming a challenge in the treatment processes. Herein, the synchronous photocatalytic reduction of Cr(VI) and oxidation of pC by silver oxide decorated on fibrous silica zirconia (AgO/FSZr) was reported. In this study, the catalysts were successfully developed using microemulsion and electrochemical techniques with various AgO loading (1, 5 and 10 wt%) and presented as 1, 5 and 10-AgO/FSZr. Catalytic activity was tested towards simultaneous photoredox of hexavalent chromium and p-cresol (Cr(VI)/pC) and was ranked as followed: 5-AgO/FSZr (96/78%) > 10-AgO/FSZr (87/61%) > 1-AgO/FSZr (47/24%) > FSZr (34/20%). The highest photocatalytic activity of 5-AgO/FSZr was established due to the strong interaction between FSZr and AgO and the lowest band gap energy, which resulted in less electron-hole recombination and further enhanced the photoredox activity. Cr(VI) ions act as a bridge between the positive charge of catalyst and cationic pC in pH 1 solution which can improve the photocatalytic reduction and oxidation of Cr(VI) and pC, respectively. The scavenger experiments further confirmed that the photogenerated electrons (e-) act as the main species for Cr(VI) to be reduced to Cr(III) while holes (h+) and hydroxyl radicals are domain for photooxidation of pC. The 5-AgO/FSZr was stable after 5 cycles of reaction, suggesting its potential for removal of Cr(VI) and pC simultaneously in the chemical industries.


Subject(s)
Silicon Dioxide , Water Pollutants, Chemical , Chromium , Cresols , Oxidation-Reduction , Zirconium
7.
J Hazard Mater ; 414: 125524, 2021 07 15.
Article in English | MEDLINE | ID: mdl-33647620

ABSTRACT

In this work, fibrous silica-titania (FST) was successfully prepared by the microemulsion method prior to the addition of three types of carbonaceous materials: graphitic-carbon nitride, g-C3N4 (CN), graphene nanoplatelets (GN), and multi-wall carbon nanotubes, MWCNT (CNT), via a solid-state microwave irradiation technique. The catalysts were characterized using XRD, FESEM, TEM, FTIR, UV-Vis DRS, N2 adsorption-desorption, XPS and ESR, while their photoactivity was examined on the degradation of toxic 2-chlorophenol (2-CP). The result demonstrated that the initial reaction rate was in the following order: CNFST (5.1 × 10-3 mM min-1) > GNFST (2.5 × 10-3 mM min-1) > CNTFST (2.3 × 10-3 mM min-1). The best performance was due to the polymeric structure of g-C3N4 with a good dispersion of C and N on the surface FST. This dispersion contributed towards an appropriate quantity of defect sites, as a consequence of the greater interaction between g-C3N4 and the FST support, that led to narrowed of band gap energy (2.98 eV to 2.10 eV). The effect of scavenger and ESR studies confirmed that the photodegradation over CNFST occurred via a Z-scheme mechanism. It is noteworthy that the addition of green carbonaceous materials on the FST markedly enhanced the photodegradation of toxic 2-CP.

8.
Trop Biomed ; 35(1): 82-90, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-33601780

ABSTRACT

Dogs can act as reservoirs, carriers, and transmitters of several zoonotic intestinal parasites that can cause serious health problems for humans. The aim of this study was to determine the prevalence of intestinal parasites in dogs in Kermanshah Province, west of Iran. Faecal samples were collected from domestic and stray dogs from 30 rural areas of Kermanshah province from August 2014 to April 2015 and were analyzed by formalin-ether sedimentation, sucrose otation technique and the modied Ziehl-Neelsen method. Out of 301 dogs examined, 230 (76.4%) were infected with at least one parasite. The incidence on the different types of intestinal parasitic species recovered from domestic and stray dogs are as follows: Toxocara leonina (20.8% and 27.6%), T. canis (7.5% and 9.4%), Taenia spp. (9.2% and 9.4%), hookworm spp. (18.3% and 33.7%), Capillaria spp. (0.8 and 1.7%), Dicrocoelium dendriticum (0.8% and 3.3%), Fasciola spp. (0.8% and 2.2%), Acanthocephal spp. (3.3% and 5.5%), Trichuris vulpis (0.8% and 1.7%), Dipylidium caninum (4.2% and 3.3%), Physaloptera spp. (6.7% and 6.6%), Cryptosporidium spp.(21.7% and 25.4%), Eimeria spp. (35.0% and 34.3%), Giardia spp. (6.7% and 12.7%), Cystoisospora spp. (7.5% and 5.5%), Blastocystis spp. (18.3% and 20.4%) and Sarcocystis spp. (6.7% and 7.2%), respectively. Signicant difference in infection rates was observed between domestic and stray dogs (P>0.05). Hookworm and Eimeria spp. were the most common intestinal helminth and protozoa detected with 83 (27.6%) out of 301 and 104 (34.6%), out of 301, respectively. There was no significant difference in prevalence and distribution of intestinal parasites between male and female dogs (P>0.05). The wide range of zoonotic parasites indicated that people residing in rural areas in Kermanshah province are at risk of exposure to these pathogens. In this respect, appropriate implementation of control programs by public health authorities and veterinarians should be taken into account.

9.
Trop Biomed ; 35(1): 91-99, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-33601781

ABSTRACT

Echinococcus granulosus, the etiologic agent of echinococcosis, is one of the most important zoonotic helminthes worldwide. Knowledge of E. granulosus species and genotypes has important implications for epidemiology, control, and prevention of diseases as well as future vaccine and drug designs. There are many molecular methods developed to define genotypes of E. granulosus, among them high resolution melting (HRM) analysis, as a new approach, is a single step and closed tube method. It is appropriate for fast screening of large number of isolates. This technique is an accurate, user friendly, cost-effective, fast and simple method, which does not need post-PCR processes. Between March and lst august 2016, of 726 sheep examined in abattoirs in Razavi Khorasan province, Northeast Iran, 109 harboured cystic echincoccosis lesions (liver samples= 65 and lung samples= 44) which were collected for analysis. Total genomic DNA was extracted from each sample and amplified for the presence of polymorphism in the mitochondrial cox1 gene of Echinococcus granulosus using a high resolution melting curve (HRM) method. A total of 109 hydatid cyst samples analyzed by PCR high-resolution melting (qPCR-HRM) curve of the cox1 gene, all isolates were identified as G1 genotype (sheep strain). G1 is the predominant genotype in sheep in northeast of Iran. The high incidence of the G1 genotype (known to be the predominant E. granulosus genotype infecting humans globally) in sheep has considerable implications for hydatid disease control programs in this area.

10.
Int J Mycobacteriol ; 5 Suppl 1: S199-S200, 2016 Dec.
Article in English | MEDLINE | ID: mdl-28043551

ABSTRACT

AIMS AND OBJECTIVES: Age increasing is caused physiological changes in the human body, such as reducing the power of the immune system. Weakened immune systems are more susceptible to bacterial infections like tuberculosis. So, this present study was performed for evaluating the prevalence of tuberculosis among Iranian elderly patients admitted to the infectious ward of a hospital. METHODS: This systematic review and meta-analysis study has been done based on PRISMA guidelines. A comprehensive search was conducted in Iranian and International databases included: Magiran, Iranmedex, IranDoc, SID, Medlib, Scopus, PubMed, Science Direct, Cochrane, Web of Science, Springer, Wiley Online Library as well as the Google Scholar search engine in the period 1990-2016 by two independent researchers using the Mesh keywords. All of the reviewed studies that had inclusion criterion were been evaluated. The diagnosis of tuberculosis were considered results of physical examination, PPD (Purified Protein Derivative) test, Blood tests, Imaging tests and sputum test. The data were analyzed by using random effects model with the software Stata-Ver.11.1. RESULTS: Five studies with a total number of 2,956 elderly patients were included. The prevalence of tuberculosis among Iranian elderly patients admitted to the infectious ward of the hospital was estimated to be 15% (95%CI: 1-30). The relationship between prevalence of tuberculosis with a year of study was not statistically significant (P=0.371). CONCLUSION: This will be the first systematic review of tuberculosis prevalence among elderly patients admitted to the infectious ward in Iran. This study showed a high prevalence of Tuberculosis and it is recommended considering tuberculosis as a differential diagnosis in elderly patients with infectious symptoms.

11.
Trop Biomed ; 33(4): 689-696, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-33579065

ABSTRACT

Antimony compounds are first line treatments for cutaneous leishmaniasis. The prognosis of the disease varies depending on the type of medicine and species. We aimed to determine the species responsible for cutaneous leishmaniasis in patients referred to Skin Diseases and Leishmaniasis Research Center in Isfahan and Bam Health Center (Kerman) in order to follow and assess the complete healing of the lesions. A total of 40 skin lesions samples were collected from patients with cutaneous leishmaniasis (CL) form January 2014 to 2015. Dermal scrapings were analyzed by examination of Giemsa-stained smears. Parasites were cultured and isolated in NNN and RPMI 1640 medium and DNA was extracted. We used PCR-RFLP assays of ITS1 genes for direct identification of Leishmania species. Treatment process was assessed after a treatment period with glucantime and healing of the studied cases was followed up. All the samples from Isfahan and Bam regions were L. major and L. tropica species respectively. In patients infected with L. major and L. tropica treated with glucantime, the shortest healing period was 40 days in 5(25%) and 60 days in 3(15.8%) patients, respectively and the longest healing period was 100 days in 1 (5%) and 160 days in 1 (5.3%) patient, respectively. The mean complete healing periods in patients with L. tropica and L. major were 100 and 58 days, respectively (P<0.001). Average recovery period for people with dry cutaneous leishmaniasis is longer than average recovery period for people with wet cutaeous leishmaniasis.

12.
Mol Biol (Mosk) ; 41(5): 934-9, 2007.
Article in Russian | MEDLINE | ID: mdl-18240576

ABSTRACT

Cryptosporidium is an important protozoan that cause diarrheal illness in humans and animals. Different species of Cryptosporidium have been reported and it is believed that species characteristics are an important factor to be considered in strategic planning for control. We therefore analyzed oocysts from human and animal isolates of Cryptosporidium by PCR-RFLP to determine strain variation in Isfahan. In total, 642 human fecal samples from children under five years of age, immunocompromised patients, and high risk persons and 480 randomly selected rectal specimens of cows and calves in Isfahan were examined. Microscopic examination showed that 4.7% (30/642) of human samples and 6.2% (30/480) of animal samples were infected with Cryptosporidium. After identification of the samples infected with the parasite, oocysts were purified and their DNA was extracted. We used PCR-RFLP analysis of a 1750-bp region of 18S rRNA gene to identify Cryptosporidium species. The human samples were infected with Cryptosporidium parvum II, C. muris, C. wrairi, and a new genotype of Cryptosporidium (GenBank accession numbers: DQ520951). The cattle samples were identified as C. parvum II, C. muris, C. wrairi, C. serpentis, C. baileyi, and a new genotype of Cryptosporidium (GenBank accession numbers: DQ520952). Also we found a new genotype infecting both human and cattle samples (GenBank accession numbers: DQ520950). In addition to demonstrating the widespread occurrence of most species of Cryptosporidium, C. parvum, we also observed extensive polymorphism within species. Furthermore, the occurrence of the same species of parasite in both animal and human samples shows the importance of the animal-human cycle.


Subject(s)
Cryptosporidiosis/genetics , Cryptosporidium/genetics , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , RNA, Ribosomal, 18S/genetics , Adult , Animals , Base Sequence , Cattle , Child, Preschool , Cryptosporidiosis/prevention & control , Cryptosporidium/isolation & purification , Host-Parasite Interactions/genetics , Humans , Immunocompromised Host , Iran , Molecular Sequence Data , Species Specificity
13.
Parasitol Res ; 96(4): 273-5, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15915364

ABSTRACT

Blastocystis hominis is commonly found in the intestinal tract of humans. Although the pathogenicity of this unicellular parasite is controversial, anti-protozoan agents are usually administered to infected individuals. At present, the first choice of chemotherapeutic agent is Metronidazole as described in the literature. In this study, we evaluated the effects of metronidazole and Trimethoprim/Sulfamethoxazole (TMP/SMX) on persons infected with B.hominis. A total of 104 subjects infected with B. hominis were admitted to the laboratory from 2002 to 2003. All individuals were non-immunocompromised and subjects were monitored for 1 year after treatment. All stool samples were microscopically examined after staining with iodine and by culturing in an egg slant medium. Of the 104 infected individuals (52+/-16 years of age, M:F=60:44) with B. hominis infection, 28 were discharging large numbers of parasites before treatment. Of 28 severely infected individuals, 12 were treated with metronidazole/250-750 mg at a regimen of 3 x/day/10 days and 4 of the 12 were eradicated. Nine individuals were treated with TMP/SMX/1 tab at a regimen of 3 x/day/10 days and 2 of the 9 were eradicated. For severe B. hominis infections, it appears that metronidazole and TMP/SMX are effective in some individuals, but not all.


Subject(s)
Anti-Infective Agents/therapeutic use , Antiprotozoal Agents/therapeutic use , Blastocystis Infections/drug therapy , Blastocystis hominis/drug effects , Metronidazole/therapeutic use , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use , Abdominal Pain/drug therapy , Abdominal Pain/parasitology , Animals , Blastocystis hominis/pathogenicity , Dose-Response Relationship, Drug , Feces/parasitology , Female , Humans , Male , Middle Aged , Surveys and Questionnaires , Treatment Outcome
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