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101.
The cellular mechanisms of blood-brain barrier (BBB) opening to endogenous albumin in the mouse brain after intracarotid infusion of solutions of protamine free base (PB) or protamine sulfate (PS) were studied using quantitative immunocytochemistry. Ultrathin sections of brain samples embedded at low temperature in Lowicryl. K4M were exposed to anti-mouse albumin antiserum followed by protein A-gold. Using morphometry, the density of immunosignals (gold particles per m2) was recorded over four compartments: vascular lumen, endothelial profiles, subendothelial space (including the basement membrane), and brain parenchyma (neuropil). In addition, the adsorption of endogenous albumin evidenced by the number of gold particles per m of the endothelial luminal plasmalemma was quantitatively evaluated. In the applied experimental conditions, PB was found to be strongly cytotoxic as indicated by the appearance of rapid degenerative changes and the disruption of the endothelial lining with concomitant clumping of the blood plasma. The action of PS was milder, offering a better opportunity for detailed ultrastructural and morphometric examination of brain samples during consecutive steps of PS action (2, 5, 10 and 30 min). As early as 10 min after infusion of PS solution, the adsorption of blood plasma albumin to the endothelial luminal surface was increased 2.5 times. Simultaneously, the immunolabelling of the endothelial profiles and subendothelial space was significantly increased. These results suggest that BBB disruption occurs through enhanced adsorption of albumin or albumin-protamine complexes to the luminal plasmalemma, followed by transendothelial vesicular transport, rather than through modification of interendothelial junctional complexes. This process appears to be focally disseminated throughout the cerebral vascular network and declines at 30 min following infusion of PS solution.  相似文献   
102.
103.
Purpose. Dextran magnetite (DM)-incorporated thermosensitive liposomes, namely thermosensitive magnetoliposomes (TMs), were prepared and characterized in order to investigate their possibility for magnetic drug targeting. Methods. TMs containing calcein were prepared at various DM concentrations by reverse-phase evaporation of dipalmitoylphosphatidylcholine (DPPC). They were evaluated for their physicochemical properties including size, DM capture, magnetite distribution within liposomes, and temperature-dependent calcein release. Moreover, a novel on-line flow apparatus with a sample injector, a coil of tubing placed in an electromagnet, and a fluorescence detector was developed for quantifying the magnetic responsiveness of TMs. This device allowed us a real-time measurement of percentage holding of TMs by magnetic field. Results. Due to water-soluble property of DM, higher contents of magnetite up to 490 mg per mmol DPPC were successfully incorporated into the liposomes with DM than with conventional magnetite (Fe3O4). Thermosensitivity and lipid integrity of TMs were not influenced by inclusion of DM. Using the on-line flow system, percentage holding of TMs by magnetic field was shown to vary with several factors; it increases as the magnetic field strength increases, the fluid flow rate decreases, the magnetite content increases, and the liposome concentration increases. Typically, at 490 mg incorporated magnetite per mmol DPPC, 0.5 ml/min-fluid flow rate, and high magnetic field strength (10 kiloGauss), approximately 100% of TMs were found to be held. Conclusions. The TMs were suggested to be useful in future cancer treatment by magnetic targeting combined with drug release in response to hyperthermia.  相似文献   
104.
The Drosophila white gene is a member of the ATP-binding cassette (ABC) transporter superfamily and is involved in the cellular uptake of tryptophan. Its human homologue gene (hW) has been mapped to chromosome 21q22.3. Tryptophan is the precursor for the neurotransmitter serotonin, which has been implicated in the regulation of mood and anxiety. The locus 21q22.3 has also been reported to be associated with mood disorders. The 3'-untranslated region (3'-UTR) in the hW gene has been shown to contain a polymorphic poly(T) region. We have identified a new polymorphism G2457A in the 3'-UTR in the present study. We examined the relationship between these polymorphisms and mood and panic disorders, and a significant association between the poly(T) polymorphisms and mood disorders was detected (P=0.039 (allele frequency)). Associations were found between the polymorphisms and mood (poly(T) polymorphism: P=0.047 (allele frequency), G2457A: P=0.040 (allele frequency), P=0.044 (genotype frequency)) and panic disorders (G2457A: P=0.026 (allele frequency), P=0.011 (genotype frequency)) in males, but not in females. These findings suggest that the hW gene may be an important gene in the control of mood and anxiety as well as one of the genetic factors related to mood disorders and panic disorder in males. The statistical significance of the association remains relatively low and larger materials facilitating further dissection of the clinical phenotype will be needed to confirm and independently validate this finding and to evaluate its significance.  相似文献   
105.
Background. Graft ischemic time (GIT) is a potential limiting factor in lung transplantation.

Methods. Seventy-four patients who underwent bilateral sequential single-lung transplantation were divided into three groups: group I, GIT less than 5 hours (n = 20); group II, GIT between 5 and 8 hours (n = 39); and group III, GIT more than 8 hours (n = 15). We compared early allograft function (ratio of arterial oxygen tension to inspired oxygen fraction and alveolar–arterial oxygen gradient), blood loss, the need for tracheostomy, the duration of ventilation, intensive care unit stay, and hospital stay. We also compared prevalences of acute and chronic rejection, airway complications, lung function test, and 2-year survival.

Results. Early allograft function in group III was significantly worse than those in groups I and II. However, there was no significant difference in any other variables of early and medium-term outcomes among the three groups. No significant correlation was detected between GIT and duration of intensive care unit stay or hospital stay.

Conclusions. The limitation of acceptable GIT could be extended from the traditionally approved 4 to 5 hours, to 5 to 8 hours or even longer.  相似文献   

106.
BACKGROUND: The role of iliac lymphadenectomy in surgery for rectal cancer remains unknown. Detailed clinicopathological data on lateral cancer extension may be needed to determine the true role of this procedure. METHODS: Seventy consecutive patients with low rectal cancer who underwent systematic iliac lymphadenectomy between 1991 and 1995 were reviewed. The iliac area was divided into five regions: (1) middle rectal root, (2) internal iliac, (3) obturator, (4) common iliac and (5) external iliac. Iliac lymph nodes that were cancer-free based on conventional pathological examination were serially sectioned at 100-microm intervals and re-examined for occult microscopic involvement. RESULTS: Occult microscopic foci were detected in five (7 per cent) of the 70 patients, and the overall incidence of lateral cancer spread was 24 per cent (17 of 70). Among patients without other sites of distant metastasis or circumferential involvement of the margin, the 5-year survival rate of those with lateral spread was 35 per cent. Although the prognosis of patients with cancer involving multiple iliac regions was poor, three of six patients with metastasis to only a single region were alive without disease at 3 years. CONCLUSION: Surgeons should be aware of the possibility of localized lateral spread, including microscopic metastasis, when determining the optimum procedure for iliac lymphadenectomy in patients with rectal cancer.  相似文献   
107.
Tracheomalacia (TM) is well known as a complication associated with esophageal atresia (EA) and tracheoesophageal fistula (TEF); however, the occurrence of TM requiring surgical treatment in a patient having EA without a tracheoesophageal fistula has never been reported. We describe herein a rare case of TM associated with EA without TEF. Respiratory distress was caused by compression of the trachea by a severely dilated upper esophageal pouch with weakness of the tracheal wall. Aortopexy was performed, and an excellent postoperative result was achieved.  相似文献   
108.
We report a case of acute renal failure associated with cryoglobulinemic glomerulonephritis. The patient, a 49-year-old woman, was referred to our hospital because of acute nephritic syndrome. After admission, she developed oliguria, and hemodialysis was instituted. Renal biopsy was performed and the specimens showed moderate endocapillary proliferation, large deposits filling the capillary lumen ("intraluminal thrombi"), and a double-contoured appearance, which are typical morphologic features of cryoglobulinemic glomerulonephritis. Immunoelectrophoresis showed a monoclonal increase of IgM kappa. On the basis of these findings, we diagnosed type II essential mixed cryoglobulinemia. Cryofiltration was performed with oral administration of prednisolone. Following the start of therapy, the patient's renal function gradually improved. Because of severe hypoproteinemia, cryofiltration was discontinued after three sessions. However, renal function recovered and was maintained with prednisolone only. This case shows that acute oliguric renal failure caused by cryoglobulinemic glomerulonephritis can be reversible if immunosuppressive therapy, together with plasmapheresis in more severe cases, is instituted promptly.  相似文献   
109.
The prevalence of antibodies against spotted fever group rickettsia (SFGR), murine typhus and Q fever were investigated in wild rats captured in Indonesia. Sera of 327 rats were collected from Jakarta and Boyolali on Java Island. The prevalences of antibodies against SFGR and murine typhus were 128 (39.1%) and 48 (14.7%), respectively. Antibodies against Q fever were not detected in these serum samples. Antibodies against SFGR were found in all species of rats (20.8–51.9%). The antibody positive rate against murine typhus in Rattus norvegicus (38.0%) was significantly higher than that in other rat species (0–4.8%, p < 0.01). The antibody positive rates against SFGR and murine typhus in rats captured in Jakarta were significantly higher than those in rats captured in Boyolali (p < 0.01). In this survey, all species of rats had antibodies against SFGR, indicating that the 4 species of tested rats (R. norvegicus, R. rattus, R. exulans, R. tiomanicus) were infected with SFGR and that SFGR may infest the whole of Java Island. Most of the rats that were antibody-positive against murine typhus were captured in Jakarta. Therefore, R. norvegicus and R. rattus are likely to be important hosts of murine typhus in Jakarta. The antibody-positive rates against SFGR and murine typhus in rats captured in the dry season were significantly higher than those in rats captured in the rainy season. This may coincide with the active periods of ticks and fleas in Indonesia.  相似文献   
110.
The aim of this study was to establish a physical performance test battery to assess the wide variation of functional fitness in older Japanese women. The criteria for sampling low/high extremity functional fitness were the amount of physical activities that older women perform on a regular basis and the distance they could move by foot. Seventeen tests related to the activities parallel to daily living (APDL) were completed for 178 women, aged 60 to 91 years. Principal component analysis of the 17 performance tests in the reference group (n = 140) yielded 5 components accounting for 63.5% of the total variance. Fourteen test items were heavily loaded on the 1st principal component, so that 31.4% of the total variance was accounted for by this component. Considering these results as well as test-retest reliability, kurtosis, and skewness of each item, the following four items were selected as a combination of test battery: (X1) repetition of the bicipital flexion/extension, (X2) walking around two cones and sitting on a chair, (X3) moving beans with chopsticks, and (X4) functional reach. Principal component analysis was again applied to these four variables so as to obtain the first principal component score of each person. As a result, the following equation was drawn: the first principal component score = 0.063X1 - 0.055X2 + 0.098X3 + 0.042X4 - 2.65. The scores averaged 0.68 +/- 0.27 for the exercise group (n = 19) (those who played croquet or other similar sports activities consistently twice or more a week); and -0.76 +/- 0.55 for the sedentary group (n = 19) (those who did no exercise and confined their activities to the home). Biserial correlation coefficient as an index of criterion-related validity was 0.67 (P < 0.05) between the scores in the exercise and sedentary groups. These results indicate that a wide range of functional fitness among older Japanese women can be assessed by the four tests.  相似文献   
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