Imaging of Oxygen Saturation and Distribution of Erythrocytes in Microvessels

Objective : To construct images of oxygen saturation and the distribution of erythrocytes in a network of microvessels. Methods : The image of a small group of microvessels under an inverted microscope was incorporated into an image processor through a video camera and was digitized. Based on the information obtained through six visible interference filters of different wavelengths, oxygen saturation and the amount of erythrocytes in microvessels were calculated with a computer. The system was applied to a microvascular bed of isolated rabbit mesentery perfused with a suspension of human erythrocytes. Results : In a steady flow, with lowering of tissue oxygen tension by superfusion with nitrogen-bubbled isotonic saline containing 20 mmol/L sodium dithionite, the decrease of oxygen saturation of erythrocytes from arterioles to venules was imaged. Simultaneously, the distribution of erythrocytes in the microvessels was imaged and the marginal cell-free layer was profiled under high magnification. No significant alteration of the erythrocyte distribution on the deoxygenation of erythrocytes was observed. The exposure of erythrocytes to acidic pH and the decrease of the flow velocity of erythrocytes increased the release of oxygen from the erythrocytes in microvessels. Conclusions : The present method will be useful for the comprehensive analysis of oxygen transfer in the microvascular network, on the basis of both changes of the oxygen saturation and the flow behavior of erythrocytes.     

Measurement of peak inspiratory flow with asthma: effect of inhaled beta2-stimulant]

This study was designed to evaluate peak inspiratory flow (PIF) and peak expiratory flow (PEF) in 24 patients with mild asthma. After inhalation of a beta2-stimulant (beta2), PIF significantly increased from 173.0 +/- 67.0 (range 70-300 L/min) to 194.0 +/- 66.7 after 1 minute, and to 199.3 +/- 63.0 after 15 minutes (p < 0.0025, and p < 0.008, respectively). PEF also significantly increased. The previous inhalation of beta2 improved the efficacy of inhalation of dry powder. This evidence should be considered in performing patient education for effective methods of inhalation.     

Mapping and ablation of clinical spontaneous perimitral atrial tachycardias using an ultra–high-resolution mapping system

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Comparison between primary closure and skin grafts of the free fibula osteocutaneous flap donor site

Purpose

This study aimed to compare the size of skin paddles, the postoperative course, and donor site complications between primary closure and skin grafts of the free fibula flap donor site.

Methods

Thirty-five consecutive patients were enrolled. Medical records were retrospectively reviewed for risk factors for delayed healing, size of skin paddles, time to resumption of gait with a mobility aid and self-ambulation, early donor site morbidity, and late donor site complaints.

Results

The harvested skin paddles were significantly wider in the skin graft group than in the primary closure group (P?=?0.02), with no difference in length (P?=?0.1). The difference in time to resuming gait with a mobility aid was also significant (P?=?0.01), but not the time to self-ambulation (P?=?0.9). Two early donor site morbidities (5.7 %) and 12 late donor site complaints (34.3 %) were found. No significant difference in the incidence of early donor site morbidity was observed between two groups. Occurrence of late donor site complaints was not affected by any risk factors.

Conclusions

The width of the harvested skin paddle, but not the length, is one of factors involved in donor site closure. Resumption of gait with a mobility aid, but not self-ambulation, may be delayed in skin graft patients.

     

Central diabetes insipidus caused by pituitary metastasis of lung cancer]

A 71-year-old man was admitted with high fever, thirst, polyposia and polyuria. After examination, lung cancer (adenocarcinoma T1NOM1, Stage IV) and central diabitus insipidus caused by pituitary metastasis of lung cancer, were diagnosed. We gave him desmopressin acetate, gamma knife surgery for pituitary metastasis and chemotherapy with paclitaxel and carboplatin, and his symptoms improved. However, his lung cancer progressed. Diabitus insipidus caused by lung cancer is rare.     

Sensory distinction between H-2b and H-2bm1 mutant mice.

Genetic polymorphism in the H-2:Qa:Tla region of chromosome 17 is associated with constitutive variation of bodily odor phenotypes which permit individual olfactory recognition among mice. To determine whether known genes in the H-2:Qa:Tla complex are concerned in the constitution of odor phenotypes, mice were tested for their ability to sense a difference between the B6/By (H-2b) and congeneic B6.C-H-2bm1 strains, which differ genetically by mutation of the H-2K gene. As in previous studies of the sensory discrimination of H-2:Qa:Tla phenotypes, mice were trained by reward in a Y maze to distinguish the odors of urine samples, and the successful distinctions of B6/By from B6.C-H-2bm1 were confirmed by transfer of training, without reward, to coded samples of urine from genetically equivalent urine donor mice which the trained mice had not previously encountered. Cosegregation of odor phenotype with H-2b and H-2bm1 was demonstrated by transfer of training to typed H-2b and H-2bm1 homozygous segregants of F2 generations of appropriate crosses. Although it is not excluded that the differences in odor phenotype which distinguish H-2b and H-2bm1 mice are directly related to the structure of the H-2b and H-2bm1 products, it is equally possible that H-2-related odor phenotypes arise from effects of H-2 genetic variation on metabolic pathways either directly, or indirectly through developmental polymorphism.     

Role of endothelin in disseminated intravascular coagulation.

We examined the changes in plasma levels of endothelin-1 (ET-1), a potent vasoconstrictor peptide, in 47 cases of disseminated intravascular coagulation (DIC) to investigate the role of ET-1 in DIC and its relation to multiple organ failure (MOF). A significant elevation of plasma levels of ET-1 was observed in some cases of DIC, especially in patients with sepsis, blastic crisis of chronic myelogenous leukemia, and cancer. However, no such significant elevation was observed in patients with acute promyelocytic leukemia (APL), acute leukemias except for APL, or non-Hodgkin lymphoma. Plasma levels of ET-1 were higher in patients with DIC with MOF than in those without MOF. Although the levels of ET-1 were decreased or remained low with clinical improvement in most DIC patients, the levels were further increased or remained high in patients who showed no improvement in DIC. It is suggested that ET-1 must play an important role in further progression of MOF with the vasoconstriction and microcirculatory disorders.