Spinal cord injury following aortic arch replacement

Surgery Today - Postoperative spinal cord injury is a devastating complication after aortic arch replacement. The purpose of this study was to determine the predictors of this complication. A group...     

Acceptable parameters for alignment of distal radius fracture with conservative treatment in elderly patients

BackgroundThere is a conflict in the treatment of distal radius fractures in elderly patients, because fracture reduction does not appear to be as strongly associated with functional outcomes as in younger patients. The purpose of this study was to evaluate radiographic findings of acceptable reduction without leading to wrist dysfunction and poor outcomes.MethodsFifty-two active and healthy elderly patients with conservatively managed distal radius fractures were included in the study. They consisted of 7 men and 45 women, all 60 years or older. Radiographic assessment included volar tilt, radial inclination and ulnar variance, and outcome evaluation included the Mayo wrist score and DASH score. As a control group, the preoperative radiographic and clinical outcomes were examined as well for 19 patients older than 60 with malunion, for whom corrective osteotomy was performed because of wrist dysfunction. The radiographic parameters and clinical outcomes were compared between the two groups in a statistical manner. Correlation coefficients of the radiographic parameters with Mayo wrist score and DASH score were analyzed by multiple regression.ResultsVolar tilt (mean —1.2°) and ulnar variance (mean 2.5 mm), as well as Mayo wrist score (mean 80.0 points) and DASH score (mean 8.6 points) in the objective group were significantly superior to those in the control group when comparing radiographic parameters and clinical outcomes. There was no significant difference between the two groups in regard to RI (mean 14.9°). Multiple regression analysis revealed that volar tilt and ulnar variance were significantly correlated with the clinical outcomes in the objective.ConclusionThe parameters of volar tilt and ulnar variance had a significant correlation with clinical outcomes. Clinical outcomes significantly worsened when those parameters exceeded a tolerable range. In elderly patients, it is important to determine an appropriate therapeutic modality for a distal radius fracture when considering the acceptable parameters for alignment.     

Effects of Heat Stress on Ocular Blood Flow During Exhaustive Exercise

The hypothesis that heat stress reduces the ocular blood flow response to exhaustive exercise was tested by measuring ocular blood flow, blood pressure, and end- tidal carbon dioxide partial pressure (P_ETCO₂) in 12 healthy males while they performed cycle ergometer exercise at 75% of the maximal heart rate at ambient temperatures of 20°C (control condition) and 35°C (heat condition), until exhaustion. The blood flows in the retinal and choroidal vasculature (RCV), the superior temporal retinal arteriole (STRA) and the superior nasal retinal arteriole (SNRA) were recorded at rest and at 6 and 16 min after the start of exercise period and at exhaustion [after 16 ± 2 min (mean ± SE) and 24 ± 3 min of exercise in the heat and control condition, respectively]. The mean arterial pressure at exhaustion was significantly lower in the heat condition than in the control condition at both 16 min and exhaustion. The degree of P_ETCO₂ reduction did not differ significantly between the two thermal conditions at either 16 min or exhaustion. The blood flow velocity in the RCV significantly increased from the resting baseline value at 6 min in both thermal conditions (32 ± 6% and 25 ± 5% at 20°C and 35°C, respectively). However, at 16 min the increase in RCV blood flow velocity had returned to the resting baseline level only in the heat condition. At exhaustion, the blood flows in the STRA and SNRA had decreased significantly from the resting baseline value in the heat condition (STRA: -19 ± 5% and SNRA: -30 ± 6%), and SNRA blood flow was lower than that in the control condition (-14 ± 6% vs -30 ± 6% at 20°C and 35°C, respectively), despite the finding that both thermal conditions induced the same reductions in P_ETCO₂ and vascular conductance. These findings suggested that the heat condition decreases or suppresses ocular blood flow via attenuation of pressor response during exhaustive exercise.

Key Points

• The ocular (retinal and choroidal) blood flow response to exhaustive exercise with heat stress is unknown.
• We hypothesized that the heat stress decreases ocular blood flow response to exhaustive exercise, since cerebral flow, which is regulated similarly to ocular flow, was reported to decrease during heat stress.
• To test this hypothesis, ocular blood flow was measured during exhaustive exercise at 20°C (control condition) and 35°C (heat condition).
• At exhaustion in the heat condition, the ocular flow response was suppressed or decreased with an attenuated pressor response.
• It is suggested that the heat condition decreases or suppresses the ocular blood flow to exhaustive exercise via attenuation of pressor response.

Key Words: Hyperthermia, exercise, healthy subjects, retinal circulation, choroidal circulation, laser-speckle flowgraphy     

Bradykinin induces NO and PGF2α production via B2 receptor activation from cultured porcine basilar arterial endothelial cells

Our previous in vitro study demonstrated that bradykinin (BK) induced relaxation and contraction of porcine basilar artery (PBA) mediated via activation of endothelial B₂ receptors. The main relaxing and contracting factors appeared to be nitric oxide (NO) and prostaglandin (PG) H₂, respectively, but not thromboxane A₂. After obtaining these findings, we succeeded in cultivating endothelial cells isolated from the PBA. Although PGH₂ has different functionally active isoforms, including PGD₂, PGE₂, and PGF_2α, we have not yet clarified which of them is responsible for BK-induced contraction. Therefore, we attempted to quantify NO and PG production from cultured porcine basilar arterial endothelial cells (PBAECs) and to identify which of the PGs was involved in this contraction. The cultured PBAECs produced NO spontaneously, and BK enhanced this production in a concentration-dependent manner. The NO synthase inhibitor Nω-nitro-l-arginine (L-NNA) and the B₂ receptor antagonist HOE-140, but not the B₁ receptor antagonist des-Arg⁹, [Leu⁸]-BK, completely abolished it. In a functional study, PGD₂, PGE₂, and PGF_2α induced concentration-dependent contractions in isolated porcine basilar arterial rings, the order of maximum contraction being PGF_2α?>?PGE₂?>?PGD₂. The cultured PBAECs produced PGD₂, PGE₂, and PGF_2α spontaneously, and BK significantly enhanced the production of PGF_2α, but not that of PGD₂ and PGE₂. The B₂, but not B₁, antagonist completely abolished the BK-enhanced production of PGF_2α. These results suggest that BK induces production of NO and PGF_2α simultaneously from PBAECs via B₂ receptor activation.     

Effects of streptozotocin-induced diabetes on circulating levels of vitamin D metabolites

In order to investigate vitamin D metabolism in insulin-deficient diabetic rats, plasma vitamin D metabolites were measured at various periods after induction of diabetes by iv administration of 60 mg/kg streptozotocin (STZ). After STZ injection, plasma insulin was significantly decreased and plasma urea nitrogen increased with the duration of diabetes, while plasma creatinine remained unchanged. Plasma calcium, 25-dihydroxyvitamin D (25(OH)D), and 24,25-dihydroxyvitamin D (24,25(OH)2D) progressively decreased. On the other hand, plasma 1,25-dihydroxyvitamin D (1,25(OH)2D) did not change at any period, but the ratio of 1,25(OH)2D to 25(OH)D became high in proportion to the severity of hypocalcaemia. Since significantly lower 25(OH)D and 24,25(OH)2D levels were observed at the later stage of diabetes, it is suggested that the altered vitamin D metabolism in diabetes is secondary to the disturbances in metabolic homeostasis derived form the insulin deficiency.     

Results from pelvic exenteration for locally advanced colorectal cancer with lymph node metastases

PURPOSE: We examined the survival benefit of pelvic exenteration for locally advanced colorectal cancer with lymph node metastases, because this issue remains controversial. METHODS: Medical records of 50 patients who underwent curative pelvic exenteration for colorectal cancer were reviewed retrospectively. Nodal metastases were examined by the clearing method in 29 patients and by the conventional manual method in 21 patients. RESULTS: Invasion to contiguous pelvic organs was present in 40 patients (80 percent) and absent in 10 patients (20 percent). Node metastases were present in 33 patients (66 percent). Operative morbidity and mortality rates were 22 percent (11 patients) and 6 percent (3 patients), respectively. Respective five-year survival rates were 60 and 80 percent in the groups with and without organ invasion (no significant difference). Five-year survival rates in patients with nodal metastases was 54.6 percent but was significantly higher, 82.4 percent, in patients without nodal metastases. Five-year survival in 28 patients with both organ invasion and nodal metastases was 53.6 percent. CONCLUSIONS: Long-term survival was afforded by pelvic exenteration for locally advanced colorectal cancer with nodal metastases.     

Nutritional status and functional capacity of community-dwelling elderly in southern Laos

Objectives

The aim of this study was to assess the nutritional status and functional capacity of 144 community-dwelling elderly in three rural ethnic groups, namely, the Oy, the Brau and the Lao, of southern Laos.

Methods

The Mini nutritional assessment (MNA) questionnaire and Determine Your Nutritional Health checklist were used to assess nutritional status. The Barthel Activities of Daily Living questionnaire and Lawton and Brody’s Instrumental Activities of Daily Living questionnaire were used to assess the functional capacity of the respondents.

Results

The MNA score results indicated that 92.5 % of Oy respondents, 85.4 % of Brau respondents and 60 % of Lao respondents were malnourished. Analysis of variance tests showed that the MNA scores of the Oy and Lao ethnic groups and of the Brau and Lao ethnic groups were significantly different ( both p < 0.01), but that there was no significant difference between the MNA scores of the Oy and Brau ethnic groups (p > 0.05). In terms of functional capacity, 47.2 % of Oy respondents, 43.9 % of Brau respondents and 20 % of Lao respondents had limitations in their activities of daily living, whereas 98.1 % of Oy respondents, 97.6 % of Brau respondents and 86 % of Lao respondents had limitations in their instrumental activities of daily living. Body mass index, reduced appetite, number of meals consumed daily and presence of common diseases predicted nutritional status in all three ethnic groups; the remaining factors differed by ethnicity. This result implies that ethnic differences and other factors, such as location of the village, services, resources within the village and respondents’ lifestyles, can affect nutritional status.

Conclusions

Because predictors of nutritional status varied by ethnicity, there is a need for area-specific interventions aimed at improving the quality of life of the elderly in these areas.