Clinical observation of orthokeratology with reducing back optic zone diameter in the treatment of myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To discuss the efficacy and safety of orthokeratology with reducing back optic zone diameter(5mm-BOZD)compared with conventional back optic zone diameter(6mm-BOZD)in the treatment of adolescent myopia.METHODS: A prospective randomized controlled trial was performed. There were 100 cases with 100 eyes of adolescent myopia(all right eye data were taken)selected from April 2016 to January 2019, the spherical degree was -1.00--5.00D. Then they were randomly divided into the two groups. The experimental group wore 5mm-BOZD orthokeratology, and the control group wore 6mm-BOZD orthokeratology. Their axis length(AL), spherical equivalent(SE), relative peripheral refraction(RPR), best corrected visual acuity(BCVA), uncorrected near visual acuity(NVA), Efron grading was applied to record the anterior segment of the eyes, corneal hysteresis(CH), corneal resistance factor(CRF), corneal-compensated intraocular pressure(IOPcc), average noninvasive Keratograph tear breakup time(NIKBUTav)and higher order aberration(RMSh) were compared between the two groups during the 1a treatment period.RESULTS: After 1a of treatment, the AL in experimental group increased 0.05±0.05mm,while it increased 0.15±0.05mm(t=-8.949, P<0.001)in control group. The SE in experimental group increased -0.18±0.27D,while it increased-0.42±0.35D(t=3.609, P=0.001)in control group. There were statistical differences in RPR changes at N30°, N20° and T30°sites between the two groups(P<0.05). There were no statistical differences in BCVA,NVA,Efron grade,CH,CRF,IOPcc,NIKBUTav and RMSh between the two groups(P>0.05).CONCLUSION:Reducing back optic zone diameter orthokeratology can correct adolescent myopia safely and more effectively during the observation period.

Distribution of Methicillin-Resistant Staphylococcus aureus (MRSA) in Apparently Healthy Population and its Susceptibility to Saponins from Dialium guineense.

Aims: The ethanolic extracts of stem bark and fruit pulp as well as saponins from Dialium guineense were assayed for antibacterial activity against Gram positive and negative strains and clinical strains of methicilin resistant Staphylococcus aureus (MRSA) isolated from different locations on human body aged 20-30 years within the University of Nigeria community. Methodology: Agar diffusion technique was adopted. Results: The results showed that MRSA is predominant in apparently healthy population of the University community with 100% in males and 92.3% females showing positive case in nasal swab, 87.5% and 96.6 % positive from ear swabs of male and female volunteers respectively; and 77.7% positive from the high vaginal swabs of females. MRSA and other clinical isolates showed higher susceptibility to saponins compared to crude extracts; however, Bacillus cereus (NRRL 14724 and 14725) were not susceptible to the saponins from D. guineense. The MICs of the saponins were 31.25 mg/mL (B. subtilis ATCC 6051, P. aeruginosa, S. typhi, S. knitambo, P. mirabilis and S. aureus), 62.50 mg/mL (E. coli) and 125 mg/mL (P. aeruginosa ATCC 10145). Comparable MICs of higher values were obtained with the crude ethanolic extracts of stem bark and fruit pulp against MRSA and clinical isolates. Conclusion: The present findings revealed wide distribution of MRSA in an apparently healthy population in Nigeria and the susceptibility patterns showed the presence of a broad spectrum antibacterial agent in D. guineense.

Studies on the antibacterial activity of Khaya senegalensis (Desr.) A. Juss) stem bark extract on Salmonella enterica subsp. enterica serovar Typhi (ex Kauffmann and Edwards) Le Minor and Popoff

<p><b>OBJECTIVE</b>To study the phytochemical screening and antibacterial activity of the stem bark extracts of Khaya senegalensis (K. senegalensis) against Salmonella enterica subsp. enterica serovar Typhi.</p><p><b>METHODS</b>The plant components were extracted using methanol, ethanol and water. The phytochemical screening of the stem bark extracts were carried out using a standard method. The antibacterial assay of the stem bark extracts against Salmonella Typhi (S. Typhi) using the agar well diffusion method with different concentrations of 50, 100, 200, 400 and 500 mg/mL and the corresponding concentrations of the control was carried out and the result compared with a standard antibiotic, amoxicillin as the control.</p><p><b>RESULTS</b>The results obtained from the phytochemical screening of the three plant bark extracts of K. senegalensis showed 10 plant secondary metabolites including saponins, tannins, reducing sugars, aldehyde, phlobatannins, flavonoids, terpenoids, alkaloids, cardiac glycoside and anthroquinones. The ethanol and aqueous extracts showed antibacterial activities against S. Typhi at concentration of 50 mg/mL with the zone diameter of inhibition (ZDI) of 14 mm and 15 mm respectively. The ethanol and aqueous extracts also showed zone diameter of inhibition of 23 mm and 25 mm respectively at 250 mg/mL and 27 mm each at 500 mg/mL. The ethanol and aqueous stem bark extracts gave the highest ZDI at 500 mg/mL while 100 mg/mL gave the least ZDI for ethanol extract and 50 mg/mL for the aqueous extract. This was followed by 400 mg/mL that gave 24 mm ZDI of the aqueous extract and 27 mm of the ethanol extract. The methanol extract showed intermediate susceptibility evidenced by ZDI of 10 mm at 100 mg/mL concentration. The methanol extract also showed antibacterial activity of 24 mm ZDI against the test organism at a higher concentration of 250 mg/mL and 26 mm at 500 mg/mL concentration. The methanol, ethanol and aqueous extracts displayed antibacterial activities against S. Typhi with a statistical significant difference at (P≤0.05). The extracts compared favourably with the standard antibiotic, the control. The minimum inhibitory concentration of the extracts was 250, 200, 200 and 100 mg/mL for methanol, ethanol, aqueous extracts and amoxicillin (control) respectively. The minimum lethal concentration of the extracts was 250, 250, 400 and 200 mg/mL for methanol, ethanol, aqueous extracts and control respectively.</p><p><b>CONCLUSIONS</b>The antibacterial properties of K. senegalensis stem bark extract can be harnessed for the production of new antibiotics or the enhancement of already existing antibiotics.</p>

Studies on the antibacterial activity of Khaya senegalensis [(Desr.) A. Juss)] stem bark extract on Salmonella enterica subsp. enterica serovar Typhi [(ex Kauffmann and Edwards) Le Minor and Popoff]

Objective: To study the phytochemical screening and antibacterial activity of the stem bark extracts ofKhaya senegalensis (K. senegalensis) against Salmonella enterica subsp. enterica serovar Typhi. Methods: The plant components were extracted using methanol, ethanol and water. The phytochemical screening of the stem bark extracts were carried out using a standard method. The antibacterial assay of the stem bark extracts against Salmonella Typhi (S. Typhi) using the agar well diffusion method with different concentrations of 50, 100, 200, 400 and 500 mg/mL and the corresponding concentrations of the control was carried out and the result compared with a standard antibiotic, amoxicillin as the control.Results:The results obtained from the phytochemical screening of the three plant bark extracts of K. senegalensis showed 10 plant secondary metabolites including saponins, tannins, reducing sugars, aldehyde, phlobatannins, flavonoids, terpenoids, alkaloids, cardiac glycoside and anthroquinones. The ethanol and aqueous extracts showed antibacterial activities against S. Typhi at concentration of 50 mg/mL with the zone diameter of inhibition (ZDI) of 14 mm and 15 mm respectively. The ethanol and aqueous extracts also showed zone diameter of inhibition of 23 mm and 25 mm respectively at 250 mg/mL and 27 mm each at 500 mg/mL. The ethanol and aqueous stem bark extracts gave the highest ZDI at 500 mg/mL while 100 mg/mL gave the least ZDI for ethanol extract and 50 mg/mL for the aqueous extract. This was followed by 400 mg/mL that gave 24 mm ZDI of the aqueous extract and 27 mm of the ethanol extract. The methanol extract showed intermediate susceptibility evidenced by ZDI of 10 mm at 100 mg/mL concentration. The methanol extract also showed antibacterial activity of 24 mm ZDI against the test organism at a higher concentration of 250 mg/mL and 26 mm at 500 mg/mL concentration. The methanol, ethanol and aqueous extracts displayed antibacterial activities against S. Typhi with a statistical significant difference at (P≤0.05). The extracts compared favourably with the standard antibiotic, the control. The minimum inhibitory concentration of the extracts was 250, 200, 200 and 100 mg/mL for methanol, ethanol, aqueous extracts and amoxicillin (control) respectively. The minimum lethal concentration of the extracts was 250, 250, 400 and 200 mg/mL for methanol, ethanol, aqueous extracts and control respectively.Conclusions:The antibacterial properties of K. senegalensis stem bark extract can be harnessed for the production of new antibiotics or the enhancement of already existing antibiotics.

Reliability of Kirby-Bauer disk diffusion method for detecting meropenem resistance among non-fermenting gram-negative bacilli.

Background: Meropenem is empirically used as a last resort for the treatment of infections by non-fermenting gram-negative bacilli (NFGNB). Minimum inhibitory concentration (MIC) determined using agar or broth dilution methods is widely used for testing meropenem resistance. However, it is not possible in resource-poor settings. Aim: A prospective study was performed to evaluate the reliability of Kirby-Bauer disk diffusion (KBDD) method for detecting meropenem resistance among NFGNB. Materials and Methods: A total of 146 NFGNB consisting of 56 Acinetobacter baumannii, 24 Acinetobacter lwoffii, 48 Pseudomonas aeruginosa and 18 Pseudomonas spp. were included in the study. All the isolates were tested simultaneously by both KBDD method and agar dilution method. Results: Very major errors were not observed with A. baumannii, A. lwoffii and P. aeruginosa, while other Pseudomonas spp. showed a very major error rate of about 5.6%. The major error rates observed with A. baumannii, A. lwoffii, P. aeruginosa and Pseudomonas spp. were 1.8%, 0%, 2.1% and 28.6%, respectively. All the isolates showed a good correlation between zone diameters (KBDD method) and MICs (agar dilution method). The sensitivity and specificity of KBDD method for detecting meropenem resistance was above 90% for all the NFGNB except Pseudomonas spp. Conclusions: The KBDD method can be reliably used for routine testing of meropenem resistance in A. baumannii, A. lwoffii and P. aeruginosa. However, further studies are needed before employing this technique for detecting meropenem resistance in Pseudomonas spp.

Analysis of Corneal Topographic Optical Zone and Decentration after Myopic Refractive Surgery

PURPOSE: To identify factors influencing the ablation center and to evaluate the size of the ablation zone after PRK and LASIK using Technolas 217 C. METHODS: This study examined the results of refractive surgery using Technolas 217 C Excimer laser with eye tracking system in 69 eyes, of which 31 underwent PRK and 38 LASIK. The ablation zone and degree of decentration were determined through corneal topography. We divided the eyes into two groups according to the degree of decentration: less than 0.5 mm as the first group, and from 0.5 to 1.0 mm as the second. The ablation zone diameter in topography was compared with the programmed preoperative optical zone. RESULTS: The only factor influencing the ablation center in the PRK group was preoperative spherical equivalent(p=0.016), and no factor influenced the ablation zone in the LASIK group. In both groups, the long axis of the ablation zone was longer than that of the programmed optical zone(p=0.003), while the short axis was shorter (p=0.001). CONCLUSIONS: After refractive surgery using Technolas 217 C Excimer laser with eye tracking system, there was no clinically significant decentration. With greater preoperative spherical equivalent, more decentered ablation was noted in the PRK group. The topographical long axis of the ablation zone was longer than that of the programmed ablation zone, while the short axis of the ablation zone was shorter. During refractive surgery, we should be aware of the possibility that the short axis of the postoperative ablation zone may be shorter than that of the programmed preoperative optical zone.

One-year Result of LASIK using 5.0 mmOptical Zone Ablation

The stability, efficacy, predictability, and safety of LASIK with 5.0 mm zone ablation was assessed and the relation between the amount of correction and the amount of ablation was also evaluated to determine how much we need to ablate the corneal stroma. In this study, we present our data on the 125 cases of myopic correction by LASIK, using ExciMed UV 200LA[Summit Technologies Inc. USA]. The patients were divided into 4 groups with preoperative myopia. About 90% of myopic error at the corneal plane was ablated and uncorrected visual acuity[UCVA], best corrected visual acuity[BCVA], intraocular pressure[IOP], and manifest refraction[MR] were checked 1 week, 1 month, 3 months, 6 months, 9 months, and 1 year after LASIK. Spherical refraction improved from -11.94D preop to -0.53D postop one year. 57.1% of eyes was within+/-0.50D and 85.7% was within+/-1.0D of emmetropia one year after LASIK. UCVA of 0.5 or better was achieved in 74.3% of eyes that is because preoperative BCVA was below 0.5 in many cases. BCVA was improved or unchanged, in 90.0% of the eyes one year after LASIK. In eyes with -20.0D of preoperative spherical value or less, ablation of about 90% of spherical value at the corneal plane made 102.9% of attempted correction 9 months after LASIK and 98.3% of attempted correction 1 year after LASIK. In eyes over -20.0D, 89.8% of attempted correction was achieved 9 months after LASIK. In conclusion, this study suggest that the ablation of 90% of preoperative myopic error at the corneal plane is reasonable for LASIK using 5.0 mmablation zone.

Prevalence of Teicoplanin-resistant Staphylococci and Evaluation of the Disk Diffusion Test for Testing the Susceptibility of Staphylococci to Teicoplanin / 감염

BACKGROUND: Teicoplanin is a glycopeptide antimicrobial agent effective against methicillin-resistant staphylococci. Decreased susceptibility of staphylococci to glycopeptides has been increasing. Teicoplanin diffuses poorly in agar and therefore the correlation between the inhibition zone diameter and the minimal inhibitory concentration(MIC) is rather poor. The purpose of this study was to evaluate the prevalence of teicoplanin-resistant staphylococci and to assess the reliability of inhibition zone diameters for determining the susceptibility of staphylococci to teicoplanin by comparing the results of the agar dilution MICs. METHODS: From June to August 1997, 290 clinical isolates of staphylococci(77 coagulase negative staphylococci(CNS), 213 Staphylococcus aureus) were collected. The antimicrobial susceptibilities to teicoplanin were determined by inhibition zone diameter and the results were compared with the MICs determined by the agar dilution method. RESULTS: Among 77 CNS strains, 75(97.4%) were susceptible and 2(2.6%) were intermediate by agar dilution method and all 213 strains of S. aureus were susceptible to teicoplanin. There was a poor correlation(r=0.50) between the zone diameters of inhibition and agar dilution MICs. In comparison with the results of disk diffusion test and agar dilution MIC, eight (2.8%) out of 290 isolates showed discrepancies (major error rates : 0.3%, minor error rates: 2.4%). CONCLUSIONS: Two(2.6%) out of 77 strains of CNS and none of 213 S. aureus strains revealed decreased susceptibility to teicoplanin. And the inhibition zone diameter was less reliable in determining the susceptibility of staphylococci than MICs. Therefore, the more effective and convenient method is needed.

Comparison of Ampicillin, Trimethoprim-Sulfamethoxazole and Rifampin therapy for Shigellosis in Admitted patients

Forty-Five cases of Shigellosis were treated with Ampicillin, TMP/SMX and Rifampin from April 1980. to November 1980. Of the 18 strains of shigellae, in-vitro sensitivity test was performed against twelve antimicrobial agents. The percentage of resistant strains was 77.8% in Ampicillin and 100% in TMP/SMX. Inhibition zone diameter by Rifampin disc was 8~10mm in all cases and clinical improvement with treatment was noted in nearly all cases, therefore we regarded inhibition zone diameter above 8mm sensitive to Rifampin. In clinical evaluation, the percentage of effectiveness by antibiotics was as follows; Ampicillin-60%, TMP/SMX-70% and Rifampin-93.3%. Rifampin appears to be the best, available drug bacteriologically and clinically for the treatment of Shilgellosis.