Histochemical study with lectins in nasal polyposis]

Changes in the membrane potential of Saccharomyces cerevisiae were monitored by the electrochromic probe 3-(4-(2-(6-(dibutylamino)-2-naphthyl)-trans- ethenyl)pyridinium)propanesulfonate (di-4-ANEPPS) that should incorporate into the plasma membrane. The probe had suitable spectral characteristics and exhibited an electrochromic shift upon a change in membrane potential but the magnitude of the response increased with time. The presence and properties of the cell wall affected the extent of cell staining. The time dependence of the fluorescent response indicated that the probe was not incorporated solely into the plasma membrane but spread gradually into the whole cell; this was confirmed by confocal microscopy. The probe is therefore suitable for assessing membrane potential changes only over time intervals up to 30 min. Longer monitoring will require either a modified staining protocol or a derivatization of the probe molecule. As found by using the dioctyl derivative di-8-ANEPPS, extending the aliphatic chains of the di-4-ANEPPS molecule does not prevent the dye from penetrating into the cell or liposome interior and, in addition, impairs staining.     

Dynamic properties of lymphatic pathways for the absorption of cerebrospinal fluid

Recent advances in small, linear-array transducers have opened new avenues for three-dimensional image acquisition from an intracardiac approach. The purpose of this study was to introduce a novel method of image acquisition using toroidal geometry, explore its fidelity of reproduction of three-dimensional cardiac anatomy, and determine whether a whole-heart scan is achievable. Acquisition was accomplished through 360-degree incremental rotation of a rigid endoscope with a side-mounted ultrasound transducer. The procedure was first tested with the use of a gelatin model to define far-field slice resolution with 1.8-degree rotational increments. Comparison of three-dimensional scans of cardiac specimens with corresponding photographs confirmed that toroidal geometry can provide a high-quality display of structures from all sides. We conclude that whole-heart three-dimensional scanning from within the cardiac chambers is possible with toroidal geometry. The quality of depicted anatomy depends on transducer location within the heart, distance from the transducer, density of slices, and image resolution. The potential of intracardiac three-dimensional ultrasound imaging includes detailed spatial evaluation of cardiac morphology, determination of appropriate placement of investigative or therapeutic devices (catheters, closure devices, etc.), and assessment of cardiac function.     

Pneumatization of the middle nasal turbinate: a CT study

Anatomic variations of the middle turbinate may be an important factor in the pathogenesis of inflammatory processes of the paranasal sinuses. A detailed analysis of coronal and axial plane CT scans of the paranasal sinuses obtained from 120 patients was performed. Paradoxical curve of the middle concha was detected in 24.2% of patients. Pneumatized middle turbinate was found in 42.5% and "true" concha bullosa in 8.3% of patients. Bilateral concha bullosa was found in 1.7% of patients.     

Histochemical detection of 4-hydroxynonenal protein in Alzheimer amyloid

Portfolio learning has not previously been reported for clinical undergraduate teaching. This open randomized study aimed to assess the effect of portfolio learning in the teaching of oncology to medical students. The project aimed to provide the student with a holistic understanding of the impact of the disease and its treatment on the patient and family, and the natural history of malignant disease, through long-term personal experience of a cancer patient. All undergraduate medical students entering Clinical Studies in October 1992 at the University of Wales College of Medicine were randomized to a study or control group. Both groups continued with the standard curriculum. Each study-group student followed a patient with cancer for 9 months, supported by bi-monthly small-group tutorials. Tutors were either general practitioners or hospital consultants, not necessarily oncologists; each was supplied with a tutor's resource pack of key oncology review papers. Students recorded triggers to learning and key items in a personal learning portfolio. Students' performances in clinical examinations and the contents of their portfolio was assessed. Final assessment was by hidden questions in the objective structured clinical examination (OSCE) in the final degree examination, when students in the study group showed higher marks in factual knowledge of oncology, particularly amongst the weaker students (P = 0.01). Those submitting portfolios for formative assessment had higher overall marks than those in the study group who did not (P = 0.04), representing the more motivated students. The whole study group showed a beneficial trend in their knowledge of oncology.     

Cotton-wick method for better drainage of middle ear

One of the advantages of polyurethane foam-covered prostheses has been that in the first 5 to 10 years after their use, the amount of capsular contraction was found much less than when similar "slick" prostheses were used. Another advance was their fixation to the surrounding tissue thus giving a more natural appearance and movement with the muscles when the arms were moved in any direction. The formation of a thick capsule also acted as a protection against gel granuloma due to rupture of the prosthesis and has been thought to be a factor in the lower capsule contraction rate. The greatest disadvantage has been that its removal was extremely difficult and this has continued up until the technique described in this paper has been introduced.     

The central nervous system and the lymphatic system. Lymphatic drainage of the cerebrospinal fluid

BACKGROUND: Recent evidence suggests that transient neurologic symptoms commonly follow lidocaine spinal anesthesia. However, information concerning factors that affect their occurrence is limited. Accordingly, to evaluate many potential risk factors, the authors undertook a prospective, multicenter, epidemiologic study. METHODS: On a voluntary basis, anesthetists at 15 participating centers forwarded a data sheet on patients who had spinal anesthesia to a research nurse blinded to the details of anesthesia and surgery. A subset was randomly selected for follow-up. The pressure [corrected] of transient neurologic symptoms, defined as leg or buttock pain, was the principal outcome variable. Logistic regression was used to control for potential confounders, and adjusted odds ratios and confidence intervals were used to estimate relative risk. RESULTS: During a 14-month period, 1,863 patients were studied, of whom 47% received lidocaine, 40% bupivacaine, and 13% tetracaine. Patients given lidocaine were at higher risk for symptoms compared with those receiving bupivacaine (relative risk, 5.1; 95% CI, 2.5 to 10.2) or tetracaine (relative risk, 3.2; 95% CI, 1.04 to 9.84). For patients who received lidocaine, the relative risk of transient neurologic symptoms was 2.6 (95% CI, 1.5 to 4.5) with the lithotomy position compared with other positions, 3.6 (95% CI, 1.9 to 6.8), for outpatients compared with inpatients, and 1.6 (95% CI, 1 to 2.5) for obese (body mass index >30) compared with nonobese patients. CONCLUSIONS: These results indicate that transient neurologic symptoms commonly follow lidocaine spinal anesthesia but are relatively uncommon with bupivacaine or tetracaine. The data identify lithotomy position and outpatient status as important risk factors in patients who receive lidocaine. Among other factors postulated to increase risk, obesity had an effect of borderline statistical significance, whereas age, sex, history of back pain, needle type, and lidocaine dose and concentration failed to affect risk.     

Embryonal morphogenesis of the intraorgan circulatory bed, lymphatic outflow pathways and innervation structures

Development of the circulation bed in human embryogenesis is brought about by a loop-like growth of vessels manifesting in proliferation, integration and morphofunctional transformation of the vascular loops. Proliferation of the loops ensures the blood inflow and reflux at all levels while their integration is followed by formation of hemocirculation system with appearance of the connective and major capillaries which serve the basis for development of true capillaries and capillary network in which precapillary arterioles and postcapillary venules can be distinguished. Hemocirculation system is completed by formation of the arteriolar and venular collaterals and arteriolo-venular anastomoses. Non-participation in the angiogenesis of the autogenic vessel endotheliocytes and their widespread necrosis give grounds to suggest that they are genetically condemned to death. Development of lymph vessels and innervation occurs simultaneously and together with blood vessels by mechanism of their centrifugal growth.     

Mechanical resilience of skin: a function of blood supply and lymphatic drainage

Diabetic ketoacidosis occurs more frequently in the young adult population than in any other age group. In a 3-year retrospective casenote review of all patients admitted with ketoacidosis to this hospital, we have defined the clinical characteristics of ketoacidosis in this age group. Young adults (< 25 years) had worse preceding glycaemic control (median HbA1 14.6 vs 10.1%, p = 0.0001) and more frequent episodes of ketoacidosis in the previous 5 years (3 vs 0, p = 0.0001) than older adults (> 25 years); on admission they had lower blood urea concentrations (p = 0.0001) and had a lower incidence of systolic hypotension (6% vs 32%, p = 0.007). There were fewer complications of ketoacidosis in the young adults, and the duration of hospital stay was less than that in the older age group (4 vs 8 days, p = 0.0003). Young adults were less likely to have a proven underlying infective or other organic precipitant for ketoacidosis, but were investigated and treated in a similar way to older adults. Insulin error or manipulation was identified in 42% of young adults; abnormal insulin treatment behaviour is likely to be the major cause of ketoacidosis in this age group.     

Histophysiological observations on the external auditory meatus, middle, and inner ear of the Weddell seal (Leptonychotes weddelli)

The assembly assay for peptide binding to class I major histocompatibility complex (MHC) is based on the ability to stabilise MHC class I molecules from mutant cell lines by the addition of suitable peptides. Such cell lines lack a functional transporter associated with antigen presentation (TAP) and as a result accumulate empty, unstable class I molecules in the ER. These dissociate rapidly in cell lysates unless they are stabilised by the addition of an appropriate binding peptide during lysis. The extent of stabilisation of class I molecules is directly related to the binding affinity of the added peptide. However, some MHC class I molecules, including HLA-B * 2705 and H-2Kk are unusually stable in their peptide-receptive state making them inappropriate for analysis using this assay or assays which depend on the ability of peptides to stabilise MHC class I molecules at the cell surface. Here we present an improved method that permits reliable measurements of peptide binding to such class I MHC molecules that are unusually stable in the absence of peptide. Cells are lysed in the presence of peptide and incubated at 4 degrees C. After 2 h, during which peptide binding to empty MHC molecules occurs, the lysate is heated to a temperature which preferentially destabilises those MHC molecules that remain empty. We have used this technique to assay peptide binding to HLA-B * 2705, as well as to the murine allele H-2Kk which also displays a stable phenotype when transfected into TAP-deficient T2 cells and show that this method represents a marked improvement over previous methods in terms of lower background signal and higher recovery of peptide bound molecules.     

Tympanometric detection of middle ear effusion in infants and young children

Tympanometry, a test of middle ear status new to clinical pediatrics, was carried out on 280 subjects, 10 days through 5 years of age. The tympanograms obtained were compared with otoscopic findings and, in 107 of the subjects, with findings at myringotomy. Seven distinct tympanometric curve types were identified and defined, based on their degree of correlation with the presence or absence of middle ear effusion. In subjects 7 months of age and older, curves suggesting normal (high) tympanic membrane compliance in combination with atmospheric or near-atmospheric middle ear air pressure were rarely associated with effusion. Conversely, curves suggesting low tympanic membrane compliance were highly correlated with the presence of effusion. Curves suggesting intermediate compliance or reduced middle ear air pressure were also correlated with effusion, but the degree of correlation was dependent on the shape of the curve. In infants less than 7 months of age, many of the ears with effusion had "normal" tympanograms, presumably because external auditory canal walls in such infants tend to be highly distensible. Tympanometry is a simple, rapid, atraumatic, valid, and objective test, easily administered by paraprofessional personnel. Its use can result in improved detection of middle ear effusion and other middle ear abnormalities, and also appears to promote improvement in diagnostic acumen.     

中厚钢板探伤缺陷的研究

根据多年的实践经验,总结了中厚钢板常见探伤缺陷,分析了缺陷的成因,并提出了解决探伤问题的工艺措施.     

Early detection of anastomotic leaks after colorectal surgery by measuring endotoxin in the drainage fluid

BACKGROUND/AIMS: Early detection of anastomotic leaks after colorectal anastomosis is essential for adequate intervention to prevent peritonitis. We investigated whether the measurement of endotoxin (LPS) concentrations in the drainage has any value for the early detection of anastomotic leaks. MATERIALS AND METHODS: Twenty two patients with colorectal anastomosis were enrolled in this study, 3 developed clinically established signs of anastomotic leaks and 19 recovered without complications. LPS concentrations in the drainage, the total daily excreted LPS amounts, leukocyte and thrombocyte counts, plasma urea and creatinine, and body temperature were measured for up to 8 days after surgery and tested for their value to detect anastomotic leaks. RESULTS: LPS concentrations in the drainage fluid and daily excreted LPS amounts of patients with anastomotic leaks were significantly higher compared to the group without anastomotic leaks. On the third postoperative day, LPS concentrations ranged from 5270 to 6750 pg/ml in patients with anastomotic leaks and from 1 to 1848 pg/ml in patients without complications. Total daily excreted LPS amounts were 270-675 ng/day in patients with anastomotic leak and 0-92 ng/day in patients without anastomotic leaks. Both LPS-related parameters allowed reliable detection of anastomotic leaks on day 3 after surgery (Student's t-Test, p < 0.0005), while leukocyte and thrombocyte counts, plasma urea and creatinine, and body temperatures of both patient groups were not significantly different at any time (p > 0.05). CONCLUSION: We found that the measurement of LPS concentrations in the drainage and the daily excreted LPS amount could be valuable parameters for the early detection of anastomotic leaks as early as on the third post-operative day.     

Gender differences in motivational pathways to college for middle class African American youths.

Using a sample of predominantly middle-class African American adolescents and parents (N = 424), the authors tested a path model linking parental expectations for children's future educational attainment, youths' motivation during Grade 11, and youths' subsequent on-time postsecondary educational progress. Parents' expectations were positively related to adolescents' educational attainment aspirations, attainment expectations, utility values (i.e., beliefs about the usefulness of education), and perceptions of racial barriers to upward mobility. Relationships between parents' expectations and youths' aspirations and expectations were mediated by youths' perceptions of parents' expectations. For boys, but not girls, Grade 11 educational expectations and utility values each uniquely predicted college attendance 1 year after high school graduation. In addition, boys' perceptions of racial barriers were negatively related to subsequent postsecondary progress through their influence on values. Findings underscore the importance of academic achievement motivation as a developmental resource for African American boys and suggest that boys are especially likely to benefit from interventions promoting positive motivational beliefs. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Quantitation of lymphatic drainage of the peritoneal cavity in sheep: comparison of direct cannulation techniques with indirect methods to estimate lymph flow

OBJECTIVE: It has been suggested that lymphatics may contribute to ultrafiltration failure in patients on continuous ambulatory peritoneal dialysis (CAPD) by absorbing dialysate and ultrafiltrate from the peritoneal cavity. In most studies lymphatic drainage has been estimated from the disappearance of an instilled tracer from the peritoneal cavity or estimated from the appearance of an intraperitoneally administered tracer in the bloodstream. However, in sheep it is possible to cannulate several of the relevant lymphatics that drain the peritoneal cavity and assess lymph drainage parameters directly. The purpose of this study was to estimate lymph drainage from the peritoneal cavity in sheep using the disappearance of tracer from the cavity and the appearance of intraperitoneally instilled tracer in the bloodstream and to compare these results with those obtained from our previous studies using cannulation techniques. DESIGN: Experiments were performed in anesthetized and nonanesthetized animals. Volumes of 50 mL/kg of Dianeal 4.25% containing 25 microCi of 125I-albumin were infused into the peritoneal cavity. RESULTS: In anesthetized sheep the calculated peritoneal lymph drainage from monitoring the disappearance of tracer from the peritoneal cavity over 6 hours was 1.873 +/- 0.364 mL/kg/hour. Monitoring the appearance of tracer in the blood gave significantly lower peritoneal lymph flow rates of 1.094 +/- 0.241 mL/kg/hour. Directly measured lymph flow rates from our earlier publication were lower still and ranged from 0.156 +/- 0.028-0.265 +/- 0.049 mL/hour/kg, depending on how we estimated the right lymph duct contribution to peritoneal drainage, since we could not cannulate this vessel. We repeated these experiments in conscious sheep. The value for lymph flow estimated from the disappearance of tracer from the peritoneal cavity was 2.398 +/- 0.617 mL/hour/kg and from the appearance of tracer in the blood, 1.424 +/- 0.113 mL/hour/kg. The lymph flow rates monitored from indwelling lymphatic catheters ranged from 1.021 +/- 0.186-1.523 +/- 0.213 mL/hour/kg (again, depending on our estimates for the right lymph duct). CONCLUSIONS: Lymph flow rates measured from indwelling lymphatic catheters provided the most conservative values for lymphatic drainage of the peritoneal cavity under dialysis conditions. Estimates of lymphatic drainage based on the appearance of tracer in the blood gave values that were on average higher. The method using the disappearance of tracer from the cavity to estimate lymph flows overestimated peritoneal lymph drainage. Fluid was lost from the peritoneal cavity, and the estimated proportion of liquid lost through lymphatic drainage depended on the technique used to measure lymph flow rates.     

Collapse of the nasal endotracheal tube in the nasal cavity

A 27-year-old female with maxillary maldevelopment was admitted for mandibular sagittal splitting osteotomy with mandibular progeny. General anesthesia was induced with 100 mg of propofol and 8 mg of vecuronium. When a soft and preformed 7.0 mm North-Polar-nasotracheal tube (Portex) was inserted into the nasopharynx through the left nasal cavity, it was very difficult to advance beyond the choana. After nasotracheal intubation, the buking became harder than before when she had been ventilated with a face mask. The peak airway pressure had reached higher than 50 cmH2O with ventilation of 500 ml tidal volume. Bronchoscopy revealed that the fiberscope (3.5 mm O.D.) could not go through the choanal stenosis, because it was too narrow. Therefore, she had to be intubated by a spiral tube, 6.0 mm I.D., through the other nasal cavity with assistance of bronchoscopy, instead of the North-Polar-tube. So, we have to pay attention to the possibility of compression and collapse of a soft nasotracheal tube in the nose of the patient with choanal stenosis due to maxillary maldevelopment.     

Cerebral amyloid angiopathy: amyloid beta accumulates in putative interstitial fluid drainage pathways in Alzheimer's disease

Cerebral amyloid angiopathy in Alzheimer's disease is characterized by deposition of amyloid beta (Abeta) in cortical and leptomeningeal vessel walls. Although it has been suggested that Abeta is derived from vascular smooth muscle, deposition of Abeta is not seen in larger cerebral vessel walls nor in extracranial vessels. In the present study, we examine evidence for the hypothesis that Abeta is deposited in periarterial interstitial fluid drainage pathways of the brain in Alzheimer's disease and that this contributes significantly to cerebral amyloid angiopathy. There is firm evidence in animals for drainage of interstitial fluid from the brain to cervical lymph nodes along periarterial spaces; similar periarterial channels exist in humans. Biochemical study of 6 brains without Alzheimer's disease revealed a pool of soluble Abeta in the cortex. Histology and immunocytochemistry of 17 brains with Alzheimer's disease showed that Abeta accumulates five times more frequently around arteries than around veins, with selective involvement of smaller arteries. Initial deposits of Abeta occur at the periphery of arteries at the site of the putative interstitial fluid drainage pathways. These observations support the hypothesis that Abeta is deposited in periarterial interstitial fluid drainage pathways of the brain and contributes significantly to cerebral amyloid angiopathy in Alzheimer's disease.     

Permeation and pathways of human calcitonin (hCT) across excised bovine nasal mucosa

In vitro permeation of human calcitonin (hCT), salmon calcitonin (sCT), and the somatostatin analog octreotide (SMS) through excised bovine nasal mucosa was studied applying donor/receiver experiments and confocal laser scanning microscopy. Permeabilities of gonadorelin, buserelin, Hoe013, and of thymopoietin fragments TP5 and TP4 were also included. Apparent permeability coefficients (Peff) ranged between 4 x 10(-5) (SMS) and 1.7 x 10(-5) cm s(-1) (TP4). Such Peff are typical for leaky-type airway epithelia. The order of permeabilities was: SMS > hCT, sCT > buserelin, Hoe013 > TP5 > TP4, LHRH. The relatively high permeability of hCT and sCT contrasted to their high molecular weight. At 37 degrees C, the permeability of hCT from mucosal to serosal (m-to-s) was found two-fold higher (p < 0.05) than from serosal to mucosal (s-to-m). Controls using 3H-mannitol showed equal permeabilities in both directions. At 4 degrees C, permeation of hCT was reduced but equal in both directions (m-to-s and s-to-m). As evaluated by confocal laser scanning microscopy, uptake studies with FITC-18-hCT revealed intracellular fluorescence in the epithelial cells, at 10 min/10 microM exposure in the form of fluorescent vesicles. By combination of these findings, an endocytotic pathway is suggested to contribute to the transport of hCT through nasal epithelium.     

Heterogeneity among peer-rejected boys across middle childhood: Developmental pathways of social behavior.

The purpose of this longitudinal study was to identify subgroups of rejected boys with different developmental pathways of aggression and prosocial behavior across the elementary school years. Peer, teacher, and parent reports and behavior observations yielded composite scores for aggression and prosocial behavior at 3 measurement waves. A cluster analysis with these composites on 87 initially rejected boys identified 4 subgroups with different developmental pathways of prosocial behavior and aggression that were associated with different patterns of sociometric acceptance and rejection over time and with social emotional adjustment in the last measurement wave. Changes in acceptance and rejection tend to precede changes in aggression and prosocial behavior. Cluster differences on social emotional adjustment indicators converged into 1 moderately discriminating factor, Social Maladaptation in Peer-Oriented Behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Role of the external nasal dilator in the management of nasal obstruction

The aim of this study is to evaluate the effect of an external nasal dilator in patients with nasal obstruction secondary to mucosal congestion (n = 33) or to septal deviation in the nasal valve area (n = 28). A group of subjects with healthy nasal cavities was tested also (n = 51). Acoustic rhinometric and rhinomanometric nasal measurements were performed with and without the dilator and before and after topical decongestion of the nasal mucosa. A visual analog scale was employed to evaluate the subjective sensation of nasal obstruction. Objective measurements showed that the external dilator increased the minimum cross-sectional area and decreased the nasal resistance significantly in all three groups (P < 0.01). The effect was more impressive in patients with septal deviation (P < 0.001). Subjective assessments reflected patency in all subjects except those in the mucosal swelling group (P = 0.06). From this study the authors conclude that the external nasal dilator offers an effective, nonsurgical therapeutic approach in the management of septal deviation that obstructs the nasal valve area. Although patients with nasal obstruction secondary to mucosal congestion showed objective improvement with the nasal dilator, these changes were not accompanied by a sensation of enhanced patency.