Walking aids and complicated orthopedic diseases are risk factors for falls in hemodialysis patients: an observational study.

BACKGROUND: Aging and an increased fall risk have been demonstrated in hemodialysis patients at home and in a facility. However, studies investigating the cause of falls to prevent fractures in dialysis rooms are scarce. This study aimed to explore the related factors for accidental falls statistically in dialysis facilities for future fall prevention. METHODS: This study included 629 hemodialysis patients with end-stage renal disease. The patients were divided into two groups: the fall and non-fall groups. The main outcome was the presence or absence of falls in the dialysis room. Univariate and multivariate logistic analyses were performed; multivariate analysis was conducted using covariates significantly correlated in the univariate analysis. RESULTS: A total of 133 patients experienced falling accidents during the study period. The multivariate analysis indicated that the use of walking aid (p < 0.001), orthopedic diseases (p < 0.05), cerebrovascular disease, and age were significantly correlated with falls. CONCLUSIONS: In the dialysis clinic, patients who use walking aids and have complicated orthopedic or cerebrovascular conditions are at a high risk of falling in the dialysis room. Therefore, establishing a safe environment may help prevent falls, not only for these patients but also among other patients with similar conditions.

Laser Doppler blood flowmeter as a useful instrument for the early detection of lower extremity peripheral arterial disease in hemodialysis patients: an observational study.

BACKGROUND: A simpler method for detecting atherosclerosis obliterans is required in the clinical setting. Laser Doppler flowmetry (LDF) is easy to perform and can accurately detect deterioration in skin perfusion. We performed LDF for hemodialysis patients to determine the correlations between blood flow in the lower limbs and peripheral arterial disease (PAD). METHODS: This retrospective study included 128 hemodialysis patients. Patients were categorized into the non-PAD group (n = 106) and PAD group (n = 22), 14 early stage PAD patients were included in the PAD group. We conducted LDF for the plantar area and dorsal area of the foot and examined skin perfusion pressure (SPP) during dialysis. RESULTS: SPP-Dorsal Area values were 82.1 ± 22.0 mmHg in the non-PAD, and 59.1 ± 20.3 mmHg in PAD group, respectively (p < 0.05). The LDF-Plantar blood flow (Qb) values were 32.7 ± 15.5 mL/min in non-PAD group and 21.5 ± 11.3 mL/min in PAD group (p < 0.001). A total of 21 non-PAD patients underwent LDF before and during dialysis. The LDF-Plantar-Qb values were 36.5 ± 17.6 mL/min before dialysis and 29.6 ± 17.7 mL/min after dialysis (p < 0.05). We adjusted SPP and LDF for PAD using logistic regression, SPP-Dorsal-Area and LDF-P were significantly correlated with PAD (p < 0.05). The receiver-operating characteristic curve analysis indicated cut-off values of 20.0 mL/min for LDF-Plantar-Qb during dialysis. CONCLUSION: LDF is a simple technique for sensitive detection of early-stage PAD. This assessment will help physicians identify early-stage PAD, including Fontaine stage II in clinical practice, thereby allowing prompt treatment.

Alanine scanning analyses of the three major loops in domain II of Bacillus thuringiensis mosquitocidal toxin Cry4Aa.

Cry4Aa produced by Bacillus thuringiensis is a dipteran-specific toxin and is of great interest for developing a bioinsecticide to control mosquitoes. Therefore, it is very important to characterize the functional motif of Cry4Aa that is responsible for its mosquitocidal activity. In this study, to characterize a potential receptor binding site, namely, loops 1, 2, and 3 in domain II, we constructed a series of Cry4Aa mutants in which a residue in these three loops was replaced with alanine. A bioassay using Culex pipiens larvae revealed that replacement of some residues affected the mosquitocidal activity of Cry4Aa, but the effect was limited. This finding was partially inconsistent with previous results which suggested that replacement of the Cry4Aa loop 2 results in a significant loss of mosquitocidal activity. Therefore, we constructed additional mutants in which multiple (five or six) residues in loop 2 were replaced with alanine. Although the replacement of multiple residues also resulted in some decrease in mosquitocidal activity, the mutants still showed relatively high activity. Since the insecticidal spectrum of Cry4Aa is specific, Cry4Aa must have a specific receptor on the surface of the target tissue, and loss of binding to the receptor should result in a complete loss of mosquitocidal activity. Our results suggested that, unlike the receptor binding site of the well-characterized molecule Cry1, the receptor binding site of Cry4Aa is different from loops 1, 2, and 3 or that there are multiple binding sites that work cooperatively for receptor binding.

Biological properties of loop-replaced mutants of Bacillus thuringiensis mosquitocidal Cry4Aa.

Cry4Aa produced by Bacillus thuringiensis subsp. israelensis (Bti) exhibits a specific toxicity to Anopheles, Aedes, and Culex larvae, which are vectors of serious diseases, and formulations of Bti are used worldwide for mosquito control. In general, domain II of the Cry toxin is believed to be important for target specificity, and three loops (loops 1, 2, and 3) in domain II have been studied extensively. In this report, to analyze the biological functions of loops 1, 2, and 3 of Cry4Aa, mutants were constructed in which one of the loops was replaced with either of the other two loops. A bioassay using Culex pipiens larvae revealed that the mosquitocidal activity was virtually lost upon replacement of loop2. The mutants in which loops 1 and/or 3 were replaced also showed decreased activity, but they still maintained some activities. This suggested that loop2, but not loops 1 and 3, was essential for the mosquitocidal activity of Cry4Aa. Proteolytic digestion revealed the involvement of loops in the stability of the Cry4Aa structure. No significant differences were observed in the amount of wild-type and mutant Cry4Aa bound to the BBMVs prepared from the C. pipiens larvae.