• Pediatric Infection and Vaccine
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• v.28 no.3
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• pp.149-159
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• 2021

Purpose: Antibiotic exposure during pregnancy may affect the fetus and newborn in many ways. This study investigated the impact of prenatal antibiotic exposure duration on neonatal outcomes in very preterm (VP) or very low birth weight (VLBW) infants. Methods: From September 2015 to December 2020, preterm infants with gestational age less than 32 weeks or with a BW less than 1,500 g who were admitted to the neonatal intensive care unit, and their mothers were enrolled. Prenatal antibiotic exposure was defined as antibiotics received by mothers before delivery, and the patients were categorized into the non-antibiotic group, short-duration (SD; ≤7 days) group, or long-duration (LD; >7 days) groups. Results: A total of 93 of 145 infants were exposed to prenatal antibiotics, among which 35 (37.6%) were in the SD group and 58 (62.4%) were in the LD group. Infants in the LD group had a significantly higher birth weight-for-gestational-age (BW/GA) Z-score than those in the non-antibiotic group, even after the adjustment for confounding factors (beta, 0.258; standard error, 0.149; P<0.001). Multivariate logistic regression analysis showed that prolonged prenatal antibiotic exposure was independently associated with death (adjusted odds ratio [aOR], 8.926; 95% confidence interval [CI], 1.482-53.775) and composite outcomes of death, necrotizing enterocolitis (NEC), and late-onset sepsis (LOS) (aOR, 2.375; 95% CI, 1.027-5.492). Conclusions: Prolonged prenatal antibiotic exposure could increase the BW/GA Z-score and the risk of death and composite outcomes of death, NEC, and LOS in VP or VLBW infants.

• Biomolecules & Therapeutics
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• v.4 no.1
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• pp.51-58
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• 1996

A new composite antibiotic, SM-101(sulbactam.metampicillin), was at dose levels of 0, 250, 500 and 1000 mg/kg/day administered intravenously to Sprague-Dawley male rats from predating to mating period and to females from premating to early gestation period. Effects of test agent on general findings and reproductive performance of parent animals and embryonic development were examined. In male parents, two deaths occurred at 1000 mg/kg. The increase in kidney weight of the 1000 mg/kg group were also observed. The decrease in body weight and food consumption were found at 500 and 1000 mg/kg. The decrease in spleen weight were seen at 250, 500 and 1000 mg/kg. In female parents, three deaths were found at 1000 mg/kg. Mating performance and fertility of parent animals were not adversely affected by all doses tested. F1 fetuses showed no changes related to treatment of SM-101. The results show that the no effect dose level(NOEL) for general toxicity of parent animals is under 250 mg/kg/day and NOELS for reproductive capability and fatal development are over 1000 mg/kg/day.

• Biomolecules & Therapeutics
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• v.4 no.1
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• pp.59-67
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• 1996

A new composite antibiotic, SM-101(sulbactam·metampicillin), was at dose levels of 0, 375, 750 and 1500 mg/kg/day administered intravenously to pregnant Sprague-Dawley rats during the organogenetic period. Two-third of dams per group were subjected to caesarean section on day 20 of pregnancy and the remaining 10 dams per group were allowed to deliver. Effects of test substance on dams, embryonal development of F1 fetuses, as well as growth, behaviour and mating performance of F1 offspring were examined. In dams, two deaths occurred at 375 and 1500 mg/kg, respectively. The decrease in the weight of adrenal glands of the 1500 mg/kg group was observed. The prolongation of pregnancy period was found at 1500 mg/kg. F1 fetuses showed no changes related to the treatment of SM-101. In F1 offspring, the increase in spleen weight was seen at all doses treated. No treatment-related abnormalities were observed in each treated group in terms of development, behaviour and reproductive performance. In F2 fetuses, no drug-induced abnormalities occurred at all doses. The results show that the no-effect dose levels (NOELS) for dams and Fl offspring are under 375 mg/kg/day and NOELs for F1/F2 fetuses are over 1500 mg/kg/day.

• Biomolecules & Therapeutics
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• v.4 no.4
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• pp.339-348
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• 1996

A new composite antibiotic, SM-101 (sulbactam·metampicillin), was at dose levels of 0, 250, 500 and 1000 mg/kg/day administered intravenously to pregnant and subsequently delivered Sprague-Dawley rats from day 17 of gestation to day 21 of lactation. Effects of test agent on dams and growth, behaviour and mating performance of Fl offspring were examined. In dams, one death occurred at 1000 mg/kg. The increase in kidney weight of the 250, 500 and 1000 mg/kg group was found. In F1 offspring, both delayed incisors eruption and decreased body weight were observed in females of the 1000 mg/kg group. The increase in the weights of liver and kidney was found in males of the 1000 mg/kg group. No treatment-related abnormalities were observed in each treated group in terms of behaviour and reproductive performance. In F1/F2 fetuses, no drug-induced abnormalities occurred at all doses tested. The results show that the no effect dose level (NOEL) of SM-101 is under 250 mg/kg/day for dams and 500 mg/kg/day for F1 offspring, and over 1000 mg/kg/day for F1/F2 fetuses.

• Economic and Environmental Geology
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• v.48 no.3
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• pp.199-204
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• 2015

In this study, we aimed to make antibiotic-intercalated smectite composites using amoxicillin and clarithromycin as hygroscopic antibiotics, and gentamicin, tobramycin and netilmicin as non-hygroscopic aminoglucosides, and to check their drug delivery potential in gastric system using preliminary in-situ column release test for clarithromycinsmectite composite. All antibiotics were successfully intercalated into the interlayer of smectite by cation-exchange reaction in the batch experiment. Equilibrium batch test showed that clarithromycin-intercalation followed Langmuir isotherm and the possible maximum amount was calculated as 1.811 mmole/g. Clarithromycin was continuously released by the solutions of pH=2, 3, and 4 and the amount was decreased with pH increase.

• Biomaterials and Biomechanics in Bioengineering
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• v.2 no.3
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• pp.159-172
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• 2015

Treatment of polymicrobial infected musculoskeletal defects continues to be a challenge in orthopaedics. This research investigated single and dual-delivery of two antibiotics, vancomycin and amikacin, targeting different classes of microorganism from a biodegradable calcium sulfate-chitosan-nHA microsphere composite scaffold. The addition of chitosan-nHA was included to provide additional structure for cellular attachment and as a secondary drug-loading device. All scaffolds exhibited an initial burst of antibiotics, but groups containing chitosan reduced the burst for amikacin at 1hr by 50%, and vancomycin by 14-25% over the first 2 days. Extended elution was present in groups containing chitosan; amikacin was above MIC ($2-4{\mu}g/mL$, Pseudomonas aeruginosa) for 7-42 days and vancomycin was above MIC ($0.5-1{\mu}g/mL$ Staphylococcus aureus) for 42 days. The antibiotic activity of the eluates was tested against S. aureus and P. aeruginosa. The elution from the dual-loaded scaffold was most effective against S. aureus (bacteriostatic 34 days and bactericidal 27 days), compared to vancomycin-loaded scaffolds (bacteriostatic and bactericidal 14 days). The dual- and amikacin-loaded scaffolds were effective against P. aeruginosa, but eluates exhibited very short antibacterial properties; only 24 hours bacteriostatic and 1-5 hours bactericidal activity. For all groups, vancomycin recovery was near 100% whereas the amikacin recovery was 41%. In conclusion, in the presence of chitosan-nHA microspheres, the dual-antibiotic loaded scaffold was able to sustain an extended vancomycin elution longer than individually loaded scaffolds. The composite scaffold shows promise as a dual-drug delivery system for infected orthopaedic wounds and overcomes some deficits of other dual-delivery systems by extending the antibiotic release.

• Korean Chemical Engineering Research
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• v.45 no.5
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• pp.473-478
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• 2007

Antibiotic composite was synthesized by coprecipitation of silver nitrate into hydroxyapatite. Adsorbed amount of silver ion was examined by the variation of concentration of silver nitrate, temperature, pressure and curing time. Optimum condition for silver-hydroxyapatite adsorption could be achieved. Physical and chemical characteristic properties of synthesized silver-hydroxyapatite were tested by ICP-MS, SEM-EDAX, DSC and XRD. Antibiotic properties for gram positive staphylococcus aureus (ATCC 6538) and gram negative escherichia coli (ATCC 25922) were tested by shake flake method.

• Membrane and Water Treatment
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• v.11 no.4
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• pp.313-321
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• 2020

ACF preparation from different materials and its application in constructed wetlands for wastewater treatment has been focused in environmental field. Different materials have been used to prepare ACF around the world. This study aims to prepare, characterize and use of ACF from loofah for removal of Tetracycline from water through composite vertical flow constructed wetlands. ACF was prepared and it was tested for characterization, later it was used for removal of Tetracycline from water through composite vertical flow constructed wetlands. In composite vertical flow constructed wetlands, three HRTs were set according to the experiment, 1D, 2D, and 3D is individually. Samples were transported immediately from collection point to laboratory for analyzing. Samples were measured for Tetracycline (TC), Total Phosphorus (TP), and Total nitrogen and COD. Tetracycline absorbance with respective 356nm was obtained good and HRT is important factor. Results show that composite vertical flow constructed wetlands with ACF from luffa is best option and it is recommended to study further deep analysis.

• Restorative Dentistry and Endodontics
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• v.43 no.3
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• pp.31.1-31.7
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• 2018

Despite considerable focus on the regenerative endodontic treatment of immature teeth with necrotic infected pulps and apical periodontitis, little data exist with regard to its possible implementation in necrotic permanent teeth with complete apical and radicular development. The present report describes the procedures and outcome of a regenerative endodontic treatment approach in 2 previously-traumatized incisors with closed apex with apical periodontitis. A 2-visit treatment procedure was employed. At initial visit, the root canals were copiously irrigated, followed by placement of a triple antibiotic paste containing ciprofloxacin, metronidazole, and clindamycin into the root canals. After 4 weeks, the antibiotic paste was removed, and apical bleeding was initiated with size 10 hand files beyond the apices. The root canals were coronally sealed with mineral trioxide aggregate, and the access cavities were restored with bonded resin composite. At post-operative 60 months, both teeth were remained asymptomatic, with the recall radiographs showing complete resolution of apical radiolucency and reestablishment of periradicular tissues. In both teeth, the dimensions of root space remained unchanged as verified by image analysis. The revitalization protocol utilizing root canal disinfection and induced apical bleeding in necrotic, closed-apex incisors may offer a clinically acceptable alternative to conventional root canal treatment.

• Archives of Reconstructive Microsurgery
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• v.4 no.1
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• pp.9-15
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• 1995

Free vascularized composite tissue transfer is more frequently underwent for reconstruction of complicated tissue defects with the recent advance of microsurgery. But postoperative result was not satifactory because of donor site morbidity, flap bulkiness and cosmetic problem. So would no longer be a problem if we can obtain the exact donor tissue required for the recipient site as allotransplantation and designing the flap. Allotransplantation has been resolved with the recent development of immunosuppressive agents, while reconstruction has made great progress with the refinement of microsurgical techniques in the last 20 years. The final sucess or failure of the operative procedure in transplantation is so utterly dependent no the availability of strategies that can control the immune system effectively, selectively, safely to allow allotransplantation of a nonvital body part. 1 used 2 strains of rats, BUF and LEW, for the limb allotransplantation as a composite tissue transfer. The primary goal of this program is to improve results in clinical transplantation by accelerating the transformation of new immunological knowledge into useful medicine. Two of the most promising new immunosuppressive compounds are FK-t06(FK) and rapamycin(RPM). Both drugs are antibiotic macrolide fungal fermentation products that presumably suppress the immune system in ways similar to cyclosporin(CyA). This study shows that two new immunosuppressive drugs compare the immunosuppressive activity and effectiveness of FK-506 and RPM for prevention of the limb allograft rejection in the rat. Additional experiments investigate the dose, route of administration and histologic findings. These data demonstrates that rapamycin is far more potent and effective than FK-506 when both compounds are administered by the intraperitoneal route, as well as prolonged graft survival significantly in a dose-route dependent manner. These results lead to the view that vascularized allograft composite tissue transfer can become a reality with the expectation of possible future application in reconstructive surgery of humans.