30-second Group Research Articles

Preliminary study of the antibacterial effect on the conjunctival sac and the influence on the corneal epithelium of domestic 5% povidone-iodine before cataract extraction

Objective: To investigate the efficacy and adverse reactions of 5% povidone-iodine in removing bacteria from the conjunctival sac with different durations. Methods: Randomized controlled study. A total of 420 patients who underwent cataract surgery in Daping Hospital, Army Medical University from December 2017 to June 2018 were selected. Non-surgical eyes (420 eyes) were selected as the study subjects and divided into 4 groups randomly: 30-second group, 1.0-min group, 2.0-min group and 3.5-min group. On the day of surgery, domestic 5% povidone-iodine was used to flush the conjunctival sac for 30 seconds, 1.0 min, 2.0 min and 3.5 min, respectively. The conjunctival sac specimens were collected for bacterial culture and bacterial identification before and after flushing the conjunctival sac with povidone-iodine. The positive rates of bacterial culture and bacterial growth were compared. The patients' ocular surface was observed and the incidence of corneal epithelial injury was recorded at 1 hour and 1 day after surgery. The positive rates of bacterial culture and corneal epithelial injury between groups were compared by Pearson chi-square test. Results: After excluding 20 patients with suspected specimens contamination, 400 patients (400 non-surgical eyes) were enrolled, including 191 males and 209 females, with an average age of 66.8 years. Before flushing the conjunctival sac, the positive rates of bacterial culture in the 30-second group, 1.0-min group, 2.0-min group and 3.5-min group were 44.8% (43/96), 43.3% (39/90), 43.1% (47/109) and 43.8% (46/105), respectively, with no statistically significant difference (χ(2)=0.066, P=0.996). After flushing, the positive rates of conjunctival sac bacterial culture in the 4 groups were 29.2% (28/96), 31.1% (28/90), 13.8% (15/109) and 13.3% (14/105), respectively. The differences between the 30-second group and 2.0-min group (χ(2)=7.308, P=0.007), between the 1.0-min group and 2.0-min group (χ(2)=8.760, P=0.003), between the 30-second group and 3.5-min group (χ(2)=7.606, P=0.006), and between the 1.0-min group and 3.5-min group (χ(2)=9.063, P=0.003) were statistically significant. At 1 hour after surgery, mild corneal epithelial injury occurred in each group, with a rate of 16.7% (16/96), 18.9% (17/90), 20.2% (22/109) and 34.3% (36/105), respectively. The differences between the 30-second group and 3.5-min group (χ(2)=8.118, P=0.004), between the 1.0-min group and 3.5-min group (χ(2)=5.804, P=0.016), and between the 2.0-min group and 3.5-min group (χ(2)=5.383, P=0.020) were statistically significant. At 1 day after surgery, there was no occurrence of new injury, and the incidence of mild corneal injury in each group was 3.1% (3/96), 5.6% (5/90), 9.2% (10/109) and 15.2% (16/105), respectively. There was statistically significant difference between the 30-second group and 3.5-min group (χ(2)=8.597, P=0.003), and between the 1.0-min group and 3.5-min group (χ(2)=4.728, P=0.030). The corneal epithelial injury healed completely at 1 week after surgery. Conclusions: The preoperative bacterial load of the conjunctival sac is more effectively reduced with 5% povidone-iodine in the 2.0-min and 3.5-min than in the 30-second and 1.0-min, and the 2-min is superior to the 3.5-min in the occurrence of corneal epithelial injury at 1 hour after surgery. Irrigation of the conjunctival sac with 5% povidone-iodine for 2 min is effective and safe, which can be an alternative measure. (Chin J Ophthalmol, 2019, 55: 509-514).

Effects of Two Different Weight Training Programs on Swimming Performance and Muscle Enzyme Activities and Fiber Type.

The effects of 2 different weight training programs incorporating bench press (BP) and pullover (PO) exercises on swimming performance, power, enzyme activity, and fiber type distribution were studied on 16 men (age = 23 ± 4 years). A 30-second group (n = 6) performed up to 20 repetitions of BP and PO in 30 seconds. The 2-minute group (n = 6) performed a maximum of 80 repetitions of BP and PO in 2 minutes. As participants reached the prescribed 20 or 80 repetitions, the weight was increased 4.5 kg. A third group (n = 4) served as nontraining controls. Exercise groups trained 3 times per week for 6 weeks. Maximal effort swims of 50 and 200 yd were performed before and after training. Training resulted in increases in work on both exercises in both groups pre- to post-training (BP 30 seconds, 722 ± 236-895 ± 250 kg; PO 30 seconds, 586 ± 252-1,090 ± 677 kg; and BP 2 minutes, 1,530 ± 414-1,940 ± 296; PO 2 minutes, 1,212 ± 406-2,348 ± 194, p ≤ 0.05). Swim performances of the 30-second group improved for both the 50-yd (32.0 ± 6.9 seconds, 30.0 ± 5.9 seconds, p ≤ 0.05) and 200-yd swims 200.0 ± 54 seconds, 182 ± 45.1 seconds (p ≤ 0.05), whereas 2-minute training improved only the 200-yd swim (198.3 ± 32.3 seconds, 186.2 ± 32.2 seconds). No changes in swim performance were observed for the control group. Triceps muscle succinate dehydrogenase activities increased (pre 3.48 ± 1.1 μmol · g(-1) wet weight per minute, post 6.25 ± 1.5 μmoles · g(-1) wet weight per minute, p ≤ 0.05) in only the 30-second training group, whereas phosphofructokinase activities and fiber type distribution did not change in either training group. This study has demonstrated that a 30-second 20-repetition weight training program, specific to the swimming musculature without concurrent swim training, improves swimming performances at both 50- and 200-yd distances.

Film thickness of crown disclosing material and its relevance to cementation

Regardless of the type of indirect restoration being fabricated, optimizing fit at cementation is a challenge. Several disclosing agents have been recommended to identify intaglio surface contacts that may result in incomplete seating and poorly adapted margins. The International Organization for Standardization has established a standard of 25 μm for the maximum film thickness for water-based cements. To accurately predict the clinical behavior of aluting cement, the disclosing agents themselves should have a film thickness no greater than 25 μm. The purpose of this study was to determine the film thickness of 2 disclosing products, a spray-on powder (Occlude Indicator Marking Spray) and a silicone disclosing agent (Fit Checker). The film thickness of the 2 disclosing products was determined by using optically flat glass cylinders according to the method set forth in International Organization for Standardization Standard 9917 for water-based cements. Because the silicone product is fast setting, the load was applied within 10 seconds of completing the mix. The spray-on product was allowed to dry before applying the load, in accordance with its intended clinical use. The film thickness of both products was determined with a load of 150 N applied for 30 seconds. Additional determinations were made for the silicone product at both 100 N and 50 N applied for 30 seconds and at 150 N applied for 90 seconds. An additional film thickness determination for the spray-on product was made with no load applied. The film thickness data for the various loads and intervals for the silicone product were analyzed with a 1-way ANOVA and the Tukey-Kramer multiple comparison test (α=.05). A t test (unequal variance, 2-tailed) was used to compare the spray-on and silicone products as measured at a load of 150 N applied for 30 seconds. The average film thickness of Fit Checker ranged from 16.7 to 23.7 μm, with the two 150-N groups significantly lower than the others, whereas that of Occlude was 67.7 μm unloaded and 48.4 μm when loaded. The film thickness of Fit Checker was significantly less than that of Occlude for the 150 N, 30-second group. Within the limitations of this study design, Fit Checker had a film thickness that satisfied the 25-μm limit imposed on water-based luting cements in the International Organization for Standardization standard, whereas Occlude Spray did not.

Comparative study of stretching modalities in healthy women: Heating and application time

A lack of muscle flexibility affects the functionality of the human body, making it difficult to carry out certain activities of daily living. The aim of the present study was to compare the technique of passive static stretching on hamstring muscles in isolation, or combined with heating techniques and different application times. Fifty women were randomly assigned to 5 groups (n = 10 each): The Microwave Diathermy Group had the hamstrings heated by microwave before stretching; Treadmill Group, in which warm-up walking was performed before stretching; 30-Second Group, in which 30 s of stretching was performed; 10-Minute Group, which involved stretching for 10 min and Control Group. In all groups, the leg extension range of motion was assessed, and the flexibility by the third finger-ground test was performed before and after application. The individuals in the experimental groups performed three stretching sessions on three consecutive days. All statistical analysis was performed with p ≤ 0.05. The results showed that all treatments were effective compared to the control group. The Treadmill Group and the 10-Minute group were superior for an acute effect (soon after the stretch--related to a decreased muscular viscoelasticity). The 10-Minute Group was the most effective for the chronic effect (long lasting--related to increased numbers of sarcomeres). A 10-minute stretch, when performed over four subsequent days, is suggested for faster increase in flexibility. The results could suggest a systemic warming (such as the one provided by a treadmill workout) before stretching for an acute gain of flexibility in the same day. It was possible to identify the inefficiencies associated with the use of microwaves in terms of stretching to gain flexibility. In fact, the values recorded were similar to stretching without any heat at all.

Inhibition of CXCL4-CCL5 Chemokine Interaction Ameliorates the Development of Abdominal Aortic Aneurysm in Mice

1.05 / 0.11mm and 1.24 / 0.09mm in the 3-minute time group (p NS between groups). Intimal hyperplasia was modest in all rats, with no significant differences in intimal wall areas. The intimal and medial wall area as a percentage of overall vessel area was 35.0 / 5.2% in the 30-second group and 36.8 / 6.6% in the 3-minute group (p NS). Conclusions: Prolonged balloon inflation time failed to produce significant changes in intimal disruption after 24 hours. At 30 days, there was no difference in the amount of intimal hyperplasia, medial wall thickening, or lumen diameter compared to standard inflation times. These results do not support changing current balloon angioplasty practices.

Viability of corneal epithelial cells and cleavage of corneal basement after ethanol effect

To evaluate the viability of corneal epithelial cells and to determine the anatomic cleavage on the epithelial basement membrane after various exposure times to 20% ethanol during epithelial flap preparation in laser-assisted subepithelial keratectomy (LASEK) in cadaver eyes. Six human cadaver eyes were exposed to 20% ethanol for 20, 30 and 40 seconds (2 eyes for each group), and another one eye was used as the control. PCNA staining was performed to determine the viability of corneal epithelial cells. Immunofluorescence staining using monoclonal antibodies against collagen VII, and immunohistological staining using monoclonal antibodies against laminin were performed to detect the anatomic location of the cleavage plane on the corneal epithelial flaps created by 20 seconds exposure to 20% ethanol in cadaver eyes. Hematoxylin and eosin staining of epithelial flaps revealed a coherent stratified epithelium. The PCNA positive rates of the epithelial cells in the flap decreased in the 20-second group, 30-second group and 40-second group successively. Immunohistological staining to laminin was patchy in the lifted flap and the remaining corneal basement membrane. Immunofluorescence to collagen VII, the main component of anchoring fibrils remained exclusively in the corneal bed. Viability of the epithelial flap decreased with longer time exposure to ethanol. The cleavage plane of the ethanol-treated corneal epithelial flap is located between the lamina lucida and the lamina densa of the basement membrane where laminin forms hemidesmosome.

Photochemically induced graded spinal cord infarction. Behavioral, electrophysiological, and morphological correlates.

Neurological and morphological outcome was evaluated in a rat model of graded spinal cord infarction initiated by a photochemical reaction. In this model, light-dye interactions induce primary microvascular stasis, resulting in consistent patterns of tissue necrosis. Four groups of rats underwent photoinduction times ranging from 30 seconds to 10 minutes. Neurological and electrophysiological functions were assessed starting 1 week after irradiation and continuing for 8 weeks. A functional neurological score was obtained by combining results from sensory and motor tasks, and electrophysiological function was evaluated from the somatosensory evoked potential recordings. In rats irradiated for short periods (30 seconds and 1 minute) mild behavioral deficits were documented. In contrast, electrical conduction was suppressed acutely in both groups; this recovered by 8 weeks to baseline or near baseline in the 30-second group but not in the 1-minute group. In rats irradiated for longer periods (5 and 10 minutes), severe behavioral and conduction abnormalities were detected at both the subacute and chronic testing periods. Although no significant difference in behavior was documented between the 5- and 10-minute groups acutely, the rats with 5-minute photoinduction time demonstrated a significant improvement in behavior over time whereas the group with 10-minute photoinduction time showed no improvement. A severe conduction block was present in both animal groups during the course of the study. Histopathological examination combined with morphometric measurements of the lesion area in cross section revealed four different degrees of spinal cord necrosis which correlated significantly with photoinduction times and neurological scores at 8 weeks. Reproducible degrees of ischemic damage to spinal cord parenchyma following primary microvascular occlusion result in a predictable sequence of behavioral and functional abnormalities, which in some cases recover with time.