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K Atsumi

Publications and source records attributed to K Atsumi.

At least 19 recordsLinked to original sources
PubMed2002

Effects of age and menopause on spinal bone mineral density in Japanese women: a ten-year prospective study.

In order to determine the age and menopause-related changes in spinal bone mineral density (BMD) in healthy Japanese women, the spinal BMD at L(2-4) was measured by dual X-ray absorptiometry (DXA) in 172 healthy Japanese women aged 31-69 years (mean age 53.1+/-6.7 years) in 1990 and 2000. This prospective study showed that there was no significant decrease of BMD in premenopausal women, but there was a significant decrease of BMD (-1.59%/year) in the early post menopausal women when compared with the premenopausal and late postmenopausal women (P <0.0001). The rate of decrease in BMD slowed down with the prolongation of the years since menopause (YSM). In postmenopausal women the annual rate of decrease in BMD for obese women was significantly lower than that for slim ones (P <0.01), suggesting that fat tissue may be effective for preventing bone loss. A multiple regression analysis of variables contributing to the annual rate of decrease in spinal BMD showed that YSM and physiological age were the most influential factors, considering other factors such as weight, height and bone mass index. In conclusion, an accelerated bone loss was seen in the early postmenopausal stage. The YSM and physiological age were the most important factors that affect the rate of bone loss in healthy postmenopausal Japanese women.

Absorptiometry, Photon↗
PubMed2001

Variables That Influence Visual Acuity After Macular Hole Surgery.

Purpose: To evaluate the variables that influence visual acuity and visual improvement after macular hole surgery.Methods: Our study included 421 eyes in which macular holes were successfully closed after surgery and followed up at least 1 year after the last surgery. Surgical techniques were conventional methods (Group 1: 350 eyes) with retinal pigment scalping of the macular hole basis added in the refractory cases (Group 2: 71 eyes). The variables used for the multiple regression were gender, age, preoperative visual acuity, hole stage, duration of symptoms, hole size, and axial length.Results: The variables that most influenced postoperative visual acuity were as follows: Group 1: gender (r = -0.011, P =.016), age (r = -0.17, P =.005), preoperative visual acuity (r = 0.51, P <.0001), duration of symptoms (r = -0.015, P <.0001), and axial length (r = -0.090, P =.045). Group 2: age (r = -0.18, P =.047), and preoperative visual acuity (r = 0.47, P <.0001).Conclusions: The variables that influenced visual acuity and visual improvement after macular hole surgery were common. In Group 1: gender, age, preoperative visual acuity, duration of symptoms, and axial length; in Group 2: age and preoperative visual acuity.

Journal Article↗
PubMed2001

Refraction and Anterior Chamber Depth Change After Vitrectomy for Pseudophakia.

Purpose: To evaluate the association between the vitreous and the refractive error in pseudophakia.Methods: Vitrectomy was performed in 67 eyes of 61 patients who underwent cataract surgery. Vitrectomy was needed for epiretinal membrane in 30 eyes, macular edema in 22 eyes, macular hole in 3 eyes, lamelar macular hole in 2 eyes, macular hole in 3 eyes, lamelar macular hole in 2 eyes, vitreous opacity in 6 eyes, and vitreous hemorrhage in 4 eyes. Refraction was measured before the operation, and 1 month, 3 months, 6 months, and 12 months after operation. Anterior chamber depth was measured in 10 eyes before the operation, and 1 month, 3 months, and 6 months after operation. We evaluated the refractive error after vitrectomy in 49 eyes that had predicted refraction.Results: The mean value of refractive change was -0.3 D 1 month postoperatively, and then gradually became positive. The variation of refraction (6-month postoperative refraction minus preoperative refraction) was negatively correlated with preoperative refraction (P =.0052, R(2) = 0.146). If preoperative refraction was more myopic than -1.5 D, then refraction became positive. If preoperative refraction was not more myopic than -1.5 D, then refraction became negative.Conclusion: About 15% of postoperative refractive error may be associated with the vitreous, but further investigation is required.

Journal Article↗
PubMed2001

[Factors related to intraoperative retinal breaks in macular hole surgery].

PURPOSE: To evaluate the factors of intraoperative retinal breaks in macular hole surgery. METHODS: This study included 558 eyes of 506 patients who underwent idiopathic macular hole surgery by one surgeon. Multiple regression was performed using the variables of gender, age, affected eye, lens status, stage, duration of symptoms, hole size, axial length, and lattice degeneration. RESULTS: The rate of retinal breaks was higher in stage 3 (16.0%) than in stage 4 (8.2%) (p = 0.014). In eyes with lattice degeneration intraoperative retinal breaks occurred in about 40% of the cases. Major factors were as follows: lattice degeneration (r = 0.24, p < 0.0001) in all eyes, stage (r = 0.090, p = 0.048) in eyes without lattice degeneration, and gender (r = -0.18, p = 0.035) in eyes of stage 4 without lattice degeneration. CONCLUSIONS: The factors of intraoperative retinal breaks in macular hole surgery were lattice degeneration in all eyes and stage 3 in eyes without lattice degeneration. The high incidence of intraoperative retinal breaks in stage 3 was mainly due to the occurrence of posterior vitreous detachment. Male gender was a significant factor associated with intraoperative retinal breaks.

Adult↗
PubMed2001

[Operculum in idiopathic macular holes].

PURPOSE: To detect the factors related to the operculum in idiopathic macular holes and present a pathogenesis of idiopathic macular holes. METHODS: This study included 583 eyes of idiopathic macular hole that underwent macular hole surgery. To detect the factor related to the operculum, the variables of age, duration of symptoms, hole size, preoperative visual acuity, refraction, axial length, refraction axial length ratio were used for the comparison between two groups and multiple regression. The success rate of surgery and postoperative visual acuity were examined whether the operculum was present or not. RESULTS: The variables that were significantly related to the operculum were as follows: refraction axial length ratio (r = 0.18, p = 0.0092) in women of stage 3, duration of symptoms (r = -0.44, p < 0.001), preoperative visual acuity (r = -0.33, p = 0.0025), and refraction axial length ratio (r = -0.22, p = 0.020) in women of stage 4, and age (r = 0.19, p = 0.047) in men of stage 3. There were no significant differences in the success rate of surgery and postoperative visual acuity whether the operculum was present or not. CONCLUSIONS: Generally, operculum tends to occur in aged and round eyes and possibly does not occur in younger and back projected eyes because of retinal fissure. In women of stage 4, the operculum is possibly a torn retina and does not occur in atrophic holes.

Adult↗
PubMed2001

Incidence of Reopening and Variables That Influence Reopening After Macular Hole Surgery.

Purpose: To evaluate the incidence and variables of reopening of macular holes after macular hole surgery.Methods: Our study included 467 eyes in which macular holes were successfully closed after surgery. Surgical techniques consisted of conventional methods (358 eyes) and scalping methods (109 eyes) with retinal pigment scalping of the macular hole basis added in such cases: reoperation, hole size (more than 0.4 disc diameter), duration of symptoms (more than 2 years). Long term incidence of reopening was predicted by life table method. After we compared reopened cases with non-reopened cases, the variables of gender, stage, biocular occurrence, age, duration of symptoms, hole size, preoperative visual acuity, refraction axial length ratio, and intraoperative retinal tears were used for the multiple regression.Results: Reopening was found in 20 eyes (5.6%) treated by conventional methods and in 10 eyes (9.2%) treated by scalping methods. Survival ratio was 87% for the conventional methods in 6 years and 79% for the scalping methods in 5 years. The variables influencing reopening were as follows: conventional methods: gender (r = 0.065, P =.19), biocular occurrence (r = 0.12, P =.026), and refraction axial length ratio (r = -0.11, P =.045); scalping methods: hole size (r = 0.14, P =.25).Conclusions: Incidence of reopening in scalping methods was high. The variables that influenced reopening after macular hole surgery were biocular occurrence and refraction axial length ratio in conventional methods. The shape of the eye may be related to reopening.

Journal Article↗
PubMed2001

[Clinical features of idiopathic macular holes-differences between sexes and stages].

PURPOSE: The purpose of this study was to evaluate the differences in the clinical features of idiopathic macular holes between sexes and stages. METHODS: Five hundred and twenty-six eyes of 480 patients with stage 3 or 4 idiopathic macular hole that had undergone vitrectomy were observed consecutively in this study. The each stage ratio, bilaterality, and affected eye were examined and the differences in age, hole duration, hole size, visual acuity, refractive power, axial length, and corneal refractive power were evaluated. RESULTS: Twenty-six % of the cases were stage 4 in males and 31% in females. There were no significant differences in bilaterality or affected eye between the sexes. Younger age and larger size were found in females of stage 3. Larger size was found in stage 4. More myopic eye and longer axial length were found in males of stage 4. There were no significant differences in hole duration and visual acuity between sexes or stages. CONCLUSIONS: In females the onset of macular hole occurred at a younger age than in males, size of the hole was larger from an earlier stage, and refractive power was less myopic. More myopic eye and longer axial length were found in stage 4, especially in males. This fact might be related to the existence of posterior vitreous detachment. We concluded that there were some differences in the mechanism of the onset and the progression of idiopathic macular hole between males and females.

Adult↗
PubMed2000

Effects of geometry of hydroxyapatite as a cell substratum in BMP-induced ectopic bone formation.

Three different types of porous hydroxyapatite with pore sizes of 100-200 micrometer in diameter-porous particles of hydroxyapatite (PPHAP), porous blocks of hydroxyapatite (PBHAP), and honeycomb-shaped hydroxyapatite (HCHAP)-were compared in terms of their abilities to induce osteogenesis when implanted subcutaneously with recombinant human BMP-2 into rats and extracted at 1, 2, 3, and 4 weeks. Histologically, direct bone formation occurred in PPHAP and PBHAP while only endochondral ossification took place in HCHAP. Interestingly, cartilage in the central zones and bone in the orifice zones of the tunnels of the HCHAP were observed at 2 weeks. After 3 weeks, the cartilage disappeared and bone formation occurred throughout the inner surface of the tunnels of the HCHAP, always leaving space for capillaries within the tunnels. Alkaline phosphatase activity and osteocalcin content were the highest in HCHAP among the three hydroxyapatite implants. These results clearly indicate that BMP-induced bone formation is highly dependent on the geometry of the carrier, which provides feasible structural factors for vascularization.

Alkaline Phosphatase↗
PubMed2000

Changes in levels of biochemical markers and ultrasound indices of Os calcis across the menopausal transition.

The aim of this longitudinal study was to investigate the changes in the levels of biochemical markers and ultrasound indices of os calcis across the menopausal transition. One hundred and ten healthy women (age 35-59 years at the 1992 baseline) participated in this 4-year population-based longitudinal study. Serum intact osteocalcin (IOC), urinary pyridinoline (Pyr), urinary deoxypyridinoline (Dpyr) and ultrasound indices were measured at baseline and after 4 years. The percentage changes in biochemical markers (% delta IOC, % delta Pyr and % delta Dpyr) and the percentage decreases in the ultrasound indices (% delta SOS, % delta BUA and % delta Stiffness) were calculated. The values of % delta IOC and % delta Dpyr in the perimenopausal subgroup (-4 to -3 years since menopause) and the values of % delta SOS and % delta Stiffness in the perimenopausal subgroup (-2 to 0 years since menopause) were significantly higher than those in other groups. Pyr was significantly correlated with % delta SOS (r = -0.467, p < 0.01) and % delta Stiffness (r = -0.330, p < 0.05) and Dpyr was significantly correlated with % delta SOS (r = -0.390, p < 0.05), % delta BUA (r = -0.353, p < 0.05) and % delta Stiffness (r = -0.454, p < 0.05), while % delta IOC was significantly correlated with % delta SOS (r = -0.278, p < 0.05), % delta BUA (r = -0.369, p < 0.01) and % delta Stiffness (r = -0.383, p < 0.01) in the peri- and postmenopausal groups. These results indicate that the increase in bone turnover occurs 4 years before menopause. However, the correlations between biochemical markers and ultrasound indices were too low to allow prediction of bone change in the individual patient.

Adult↗
PubMed2000

CP6679, a new injectable cephalosporin. Part 1: synthesis and structure-activity relationships.

A series of cephalosporins bearing a 5,5-fused ring system, an (imidazo[5,1-b]thiazolium-6-yl)methyl group, at the C-3 position were synthesized and evaluated for in vitro antibacterial activities. CP6679 (1s) and its analogues showed potent antibacterial activities against gram-positive and gram-negative bacteria, including Pseudomonas aeruginosa. They were also highly active against methicillin-resistant Staphylococcus aureus (MRSA). CP6679 (1s) showed more potent antibacterial activity than ceftazidime (CAZ) or cefpirome (CPR) against Pseudomonas aeruginosa and MRSA.

Ceftazidime↗
PubMed2000

[Variables that influence visual acuity after macular hole surgery].

PURPOSE: To evaluate the variables that influence visual acuity and visual improvement after macular hole surgery. METHODS: Our study included 421 eyes in which maculor holes were successfully closed after surgery and followed up at least 1 year after the last surgery. Surgical techniques were conventional methods (Group 1: 350 eyes) with retinal pigment scalping of the macular hole basis added in the refractory cases (Group 2: 71 eyes). The variables used for the multiple regression were gender, age, preoperative visual acuity, hole stage, duration of symptoms, hole size, and axial length. RESULTS: The variables that most influenced postoperative visual acuity were as follows: Group 1: gender (r = -0.011, p = 0.016), age (r = -0.17, p = 0.005), preoperative visual acuity (r = 0.51, p < 0.0001), duration of symptoms (r = -0.015, p < 0.0001), and axial length (r = -0.090, p = 0.045). Group 2: age (r = -0.18, p = 0.047), and preoperative visual acuity (r = 0.47, p < 0.0001). CONCLUSIONS: The variables that influenced visual acuity and visual improvement after macular hole surgery were common. In Group 1: gender, age, preoperative visual acuity, duration of symptoms, and axial length; in Group 2: age and preoperative visual acuity.

Adult↗
PubMed2000

[Incidence of reopening and variables that influence reopening after macular hole surgery].

PURPOSE: To evaluate the incidence and variables of reopening of macular holes after macular hole surgery. METHODS: Our study included 467 eyes in which maculor holes were successfully closed after surgery. Surgical techniques consisted of conventional methods (358 eyes) and scalping methods (109 eyes) with retinal pigment scalping of the macular hole basis added in such cases: reoperation, hole size (more than 0.4 disc diameter), duration of symptoms (more than 2 years). Long term incidence of reopening was predicted by life table method. After we compared reopened cases with non-reopened cases, the variables of gender, stage, biocular occurrence, age, duration of symptoms, hole size, preoperative visual acuity, refraction axial length ratio, and intraoperative retinal tears were used for the multiple regression. RESULTS: Reopening was found in 20 eyes (5.6%) treated by conventional methods and in 10 eyes (9.2%) treated by scalping methods. Survival ratio was 87% for the conventional methods in 6 years and 79% for the scalping methods in 5 years. The variables influencing reopening were as follows: conventional methods: gender (r = 0.065, p = 0.19), biocular occurrence (r = 0.12, p = 0.026), and refraction axial length ratio (r = -0.11, p = 0.045); scalping methods: hole size (r = 0.14, p = 0.25). CONCLUSIONS: Incidence of reopening in scalping methods was high. The variables that influenced reopening after macular hole surgery were biocular occurrence and refraction axial length ratio in conventional methods. The shape of the eye may be related to reopening.

Adult↗
PubMed2000

[Refraction and anterior chamber depth change after vitrectomy for pseudophakia].

PURPOSE: To evaluate the association between the vitreous and the refractive error in pseudophakia. METHODS: Vitrectomy was performed in 67 eyes of 61 patients who underwent cataract surgery. Vitrectomy was needed for epiretinal membrane in 30 eyes, macular edema in 22 eyes, macular hole in 3 eyes, lamelar macular hole in 2 eyes, vitreous opacity in 6 eyes, and vitreous hemorrhage in 4 eyes. Refraction was measured before the operation, and 1 month, 3 months, 6 months, and 12 months after operation. Anterior chamber depth was measured in 10 eyes before the operation, and 1 month, 3 months, and 6 months after operation. We evaluated the refractive error after vitrectomy in 49 eyes that had predicted refraction. RESULTS: The mean value of refractive change was -0.3 D 1 month postoperatively, and then gradually became positive. The variation of refraction (6-month postoperative refraction minus preoperative refraction) was negatively correlated with preoperative refraction (p = 0.0052, R2 = 0.146). If preoperative refraction was more myopic than -1.5 D, then refraction became positive. If preoperative refraction was not more myopic than -1.5 D, then refraction became negative. CONCLUSION: About 15% of postoperative refractive error may be associated with the vitreous, but further investigation is required.

Aged↗
PubMed2000

[Artificial organ].

Explore the source record for details and available documents.

Artificial Organs↗
PubMed2000

[Factors related to initial success in macular hole surgery].

PURPOSE: To evaluate the factors of initial success in macular hole surgery. METHODS: This study included 526 eyes of 480 patients who underwent idiopathic macular hole surgery by one and the same surgeon. Surgical methods included conventional method (392 eyes), retinal pigment epithelium (RPE) scalping (61 eyes), internal limiting membrane (ILM) removal (62 eyes), and RPE scalping combined with ILM removal (11 eyes). To evaluate the factors of initial success multiple regression was performed using the variables of (gender, age, stage, duration of symptoms, hole size, axial length, and preoperative visual acuity). RESULTS: The rate of initial success was 81.4% in all eyes, 80.9% in the conventional method, 78.7% in RPE scalping, 83.9% in ILM removal, and 100% in RPE scalping combined with ILM removal. Significant factors of initial success were as follows: gender (r = -0.091, p = 0.053), age (r = -0.14, p = 0.0062), duration of symptoms (r = -0.23, p < 0.0001), hole size (r = -0.23, p < 0.0001), and axial length (r = -0.21, p < 0.0001) in the conventional method, hole size (r = -0.56, p = 0.0006) in ILM removal and stage (r = -0.43, p = 0.0011) and preoperative visual acuity (r = 0.30, p = 0.018) in RPE scalping. CONCLUSIONS: Significant factors of initial success were being male being young, shorter duration of symptoms, smaller hole size, and shorter axial length in the conventional method, smaller hole size in ILM removal and stage 4 and better preoperative visual acuity in RPE scalping method.

Adult↗
PubMed2000

[Clinical features of idiopathic macular holes].

PURPOSE: The purpose of this study was to evaluate the clinical features of idiopathic macular holes. MATERIALS AND METHODS: The clinical features were examined in consequentive 526 eyes of 480 patients with idiopathic macular hole who underwent vitrectomy. RESULTS: Sixty-seven% of the patients were female. The mean onset age was 64.4 years of age and 60% of the cases were in their 60's at the time of onset. The mean refractive value was -0.66 dioptor and 40% of the cases were emmetropia with a refractive value between -1.0 dioptor and +1.0 dioptor. The onset age was positively correlated with refractive value. The visual acuity was negatively correlated with onset age, duration after onset, and the size of the macular hole. The duration was positively correlated with onset age. The size of the macular hole was positively correlated with age and duration. The factors for good visual acuity were determined by bilaterality, youth, or small size. Also we found the factors for large size of macular holes to be female gender, long duration of the hole, being in stage 4, and low visual acuity. CONCLUSIONS: The incidence of idiopathic macular hole is seen more in eyes of patients in their 60's and in emmetropic eyes. Patients with myopic eyes tend to have younger onset. The size of the macular hole in females tends to be larger than in males.

Adult↗
PubMed1999

Effects of sevoflurane anesthesia on plasma inorganic fluoride concentrations during and after cardiac surgery.

PURPOSE: Sevoflurane metabolism results in the production of inorganic fluoride, which is known to be nephrotoxic. Since marked changes in body temperature and hemodynamics in cardiac surgery affect sevoflurane metabolism, plasma inorganic fluoride concentrations may differ in this situation compared with other types of surgery. We therefore measured plasma inorganic fluoride concentrations during and after sevoflurane anesthesia in patients undergoing cardiac surgery. METHODS: Sixteen patients undergoing coronary artery bypass grafting or valve replacement were premedicated with 5-10 mg midazolam and 0.5 mg scopolamine injected intramuscularly. Anesthesia was induced with 5-10 mg midazolam, 0.5-1 mg fentanyl, and 0.12-0.15 mg.kg(-1) vecuronium. Following tracheal intubation, anesthesia was maintained with oxygen, sevoflurane, and fentanyl. At the onset of cardiopulmonary bypass (CPB), sevoflurane was discontinued, and additional fentanyl, midazolam, and pancuronium were administered. Plasma inorganic fluoride concentrations were measured before anesthesia, immediately before and after CPB, and at 0, 2, 6, 12, 24, and 48 h after anesthesia. RESULTS: The individual maximum plasma inorganic fluoride concentration was 19.2 +/- 7.2 micromol.l(-1) (mean +/- SD; range, 9.2-36.7). The mean plasma inorganic fluoride concentrations increased during anesthesia, but the rate of increase decreased after the initiation of CPB. Concentrations peaked at 2 h after anesthesia and decreased thereafter. The concentrations in three cases continued to increase 2 h after anesthesia. CONCLUSION: The plasma inorganic fluoride concentrations observed in patients undergoing cardiac surgery were below nephrotoxic levels. However, the decrease in mean fluoride concentration after anesthesia was slower than that in the previous study in general surgical patients.

Journal Article↗