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21.
Polymorphonuclear leukocytes (PMN) with a deficiency of the complement receptor type 3 (CR3) membrane glycoprotein family have impairments in the ability to adhere to surfaces as well as chemotactic and phagocytic defects, processes that require a functional contractile apparatus. PMN from the patient with neutrophil actin dysfunction (NAD) displayed similar functional characteristics to those with CR3 deficiency suggesting the two disorders may be the same disease. In order to evaluate the relationship between CR3 deficiency and actin assembly, actin filament assembly was measured in PMN from six previously reported homozygotes (two severe and four moderate CR3-deficient patients) as well as five heterozygotes for CR3 deficiency. PMN from all patients had normal unstimulated concentrations of F-actin and after exposure to the chemotactic peptide FMLP (5 x 10(-7) mol/L for 5 to 40 seconds at 25 degrees C) assembled actin normally. Pretreatment of normal PMN with concentrations of monoclonal anti-alpha CR3 antibody, capable of blocking PMN adherence, also failed to impair FMLP- induced actin filament assembly. CR3 glycoprotein expression was measured in PMNs from the mother, father, and older sister of the NAD patient (N Engl J Med 291:1093, 1974). Actin filament assembly was recently shown to be defective in PMNs from all three family members. The total concentrations of the alpha and beta CR3 subunits were below normal in PMN detergent extracts from the mother (25% of simultaneous controls) and older sister (56% of control). PMN surface expression of these two subunits was also found to be depressed (mother, 50%; older sister, 63% of control). These findings suggest these two NAD family members are heterozygote carriers for CR3 deficiency as well as NAD. Simultaneous studies of the father, however, demonstrated normal total concentrations of both the alpha and beta CR3 subunits (126% of controls) as well as normal surface expression of both subunits after phorbol myristate acetate stimulation and incubation at 37 degrees C (mean, 112% of controls) but slightly lower than normal levels after FMLP stimulation (mean, 83%). These findings indicate that CR3 deficiency generally is not associated with defective actin filament assembly and support the conclusion that NAD represents a unique kindred in which PMN actin function differs from previously reported genotypes of CR3 deficiency.  相似文献   
22.
The first recorded case of lymphoma of the bladder was reported by Eve and Chaffey in 1885. Malignant lymphoma of the bladder can be classified into one of three different clinical groups: 1) Primary lymphoma localized to the bladder; 2) Lymphoma presenting in the bladder as the first sign of disseminated disease (non-localized lymphoma); 3) Recurrent bladder involvement by lymphoma in patients with a history of malignant lymphoma (secondary lymphoma). Primary extranodal marginal zone lymphoma of mucosa associated lymphoid tissue (MALT type) of the urinary bladder, first described by Kempton et al in 1990, is the most common primary bladder lymphoma and associated with an excellent prognosis. We present a patient with gross hematuria who was found to have a primary bladder lymphoma and review the relevant literature.  相似文献   
23.
Musculoskeletal disorders gradually affect workers in different parts of the world, compromising their occupational health and quality of life. Professionals exposed to these symptoms include the motorcycle taxi driver, whose pain is due to the overuse of the musculoskeletal system and little time to recover it.To identify the prevalence of musculoskeletal symptoms in motorcycle taxi drivers in the city of Rio Branco, Acre, Brazil, West Amazon.Cross-sectional study, involving 296 motorcycle taxi drivers in the city of Rio Branco-Acre, Brazil, male, from December 2016 to February 2017. The Nordic Musculoskeletal Questionnaire was used to collect information related to symptoms (pain, discomfort, or numbness) in the last 7 days of work. For the exclusion criteria were, being female; not reside outside the city of Rio Branco, Acre; having less than 3 months of work activity; not be carrying out their work activities at the time of application of the protocol; be limited by clinical or physical issues at the time of application of the protocol. The data obtained in the questionnaire were entered into the Epidata program (Epidata Association, Odense, Denmark) and then transferred to the STATA 10 statistical program (Stata Corp., College Station), for categorization and statistical analysis.The study population is over 36 years old; most reported having a partner and a higher education level. The average daily working hours of the participants were 12 hours, with the majority working over 12 hours daily. Most of the epidemiological variables factors were associated with musculoskeletal pain when the prevalence and prevalence ratio analyzes were performed. Higher prevalence of musculoskeletal symptoms in the lumbar region is with 17.9%. In the lower limbs, the most affected joint was the ankle (5.7%), followed by the hip (5.07%) and knee (5.07%), respectively. Insomnia was present in 55.35% and self-reported headache in 49.4% of participants.The musculoskeletal disorders generated by the daily service of motorcycle taxi drivers are directly affecting the quality of life of these professionals.  相似文献   
24.
Scott  CF; Sinha  D; Seaman  FS; Walsh  PN; Colman  RW 《Blood》1984,63(1):42-50
The traditional coagulant assay for plasma factor XI suffers from a relatively high coefficient of variation, the need for rare congenitally deficient plasma, and a poor correlation between precision and sensitivity. We have developed a simple functional amidolytic assay for factor XI in plasma using the chromogenic substrate PyrGlu-Pro-Arg- p-nitroanilide (S-2366). After inactivation of alpha 1-antitrypsin, CI inhibitor, and other plasma protease inhibitors with CHCI3, plasma was incubated with kaolin, in the absence of added calcium, which limited the enzymes formed to those dependent on contact activation. Soybean trypsin inhibitor was used to minimize the action of kallikrein on the substrate. Once the reaction was complete, corn trypsin inhibitor was used to inactive factor XIIa, the enzyme generated by exposure of plasma to negatively charged surfaces, which had activated the factor XI. The assay is highly specific for factor XI, since plasma totally deficient in that zymogen yielded only 1%-3% of the enzymatic activity in normal plasma under identical conditions. The requirements for complete conversion of factor XI to XIa in plasma within 60 min were, respectively, factor XII, 0.6 U/ml, and high molecular weight kininogen, 0.2 U/ml. Prekallikrein was not an absolute requirement for complete activation but did accelerate the reaction. The intraassay coefficient of variation was 3.4%, and the mean of 35 normal plasmas was 1.00 U +/- 0.24 SD. In addition, a new rapid radioimmunoassay was devised using staphylococcal protein A as the precipitating agent for a complex of factor XI antigen with monospecific rabbit antibody. The mean was 1.01 U +/- 0.30 SD. The correlation coefficients for amidolytic versus coagulant and amidolytic versus radioimmunoassay were r = 0.95 for the former and 0.96 for the latter. Thus, a simple, accurate amidolytic assay and a radioimmunoassay have been devised for measuring factor XI in plasma that correlate well with the coagulant activity of factor XI, as determined in our laboratory.  相似文献   
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The aims of this pilot study were to verify which muscle strength tests better explain bone mineral content (BMC) of the femoral neck and lumbar spine and to develop predictive equations to estimate femoral neck and lumbar spine BMC. Twenty-nine subjects aged 56–76 years old (12 women and 17 men) participated in the study. Femoral neck and lumbar spine BMC was evaluated by Dual X-ray absorptiometry (DXA). Muscle strength measurements included maximal isometric voluntary contractions of knee extensors and flexors, vertical jump, 5-repetition maximum of the leg press (5-RMLP) and seated leg curl (5-RMLC), and handgrip strength. Women presented a moderate to strong correlation between femoral neck BMC and 5-RMLP (r = 0.819), 5-RMLC (r = 0.879), knee extensors peak torque (r = 0.699), and handgrip strength (r = 0.663), as well as between lumbar spine BMC and the 5-RMLP test (r = 0.845) and manual grip strength (r = 0.699). For females, the 5-RMLP and 5-RMLC tests most fully explained femoral neck BMC (R2 = 0.859) and the 5-RMLP test and body mass explained lumbar spine density (R2 = 0.757) for females. Men did not present correlations between BMC and strength variables. For females, the 5-RMLP and 5-RMLC variables explained the variations of femoral neck BMC, while 5-RMLP and body mass explained lumbar spine BMC. Future studies should evaluate a larger sample size and prioritize the strength tests with a greater predictive capacity.  相似文献   
27.
Interest in hybrid monolayers with arrangements that differ from that of the honeycomb lattice has been growing. However, systematic investigations on the properties of these structures are still lacking. In this work, we combined density functional theory (DFT) and molecular dynamics (MD) simulations to study the stability and electronic properties of nanosheets composed of B, C, and N atoms arranged in the pattern of the carbon allotrope graphenylene. We considered twenty structures with varied atomic arrangements and stoichiometries, which we call BxCyNz hybrid graphenylenes. We calculated the formation energy for each arrangement, and found that it decreases as the number of B–C and N–C bonds decreases. We also found that the structure with minimum energy has stoichiometry B2CN and an atomic arrangement with BN and C stripes connected along the zigzag direction. Regarding the electronic properties, we found that all investigated structures are semiconductors, with band gaps ranging from 0.14 to 1.65 eV. Finally, we found that the optimized hybrid lattices presented pores of varied sizes and shapes. This diversity in pore geometry suggests that these structures might be particularly suited for molecular sieve applications.

We combine density functional theory and molecular dynamics to investigate the stability and electronic properties of 20 structures composed of boron, carbon, and nitrogen arranged in the pattern of the two-dimensional carbon allotrope graphenylene.  相似文献   
28.
We analyzed spatiotemporal patterns of 8,756 schistosomiasis-related deaths in Brazil during 2000–2011 and identified high-risk clusters of deaths, mainly in highly schistosomiasis-endemic areas along the coast of Brazil’s Northeast Region. Schistosomiasis remains a neglected public health problem with a high number of deaths in disease-endemic and emerging focal areas.  相似文献   
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Background

Resistance training has proven to be an excellent method for counteracting aging physical dysfunctions. However, its application in the liquid environment is not yet fully elucidated.

Aim

To investigate the effects of water-based resistance training (WBRT) with the concentric phase performed as fast as possible, compared to conventional resistance training (CRT), on physical functional capacity, muscle strength, and body composition in older women.

Methods

Thirteen healthy older women participated in the WBRT and 11 in the CRT. Estimation statistics focused on the effect size of the experiment/intervention were used. We also analyzed the intervention effect based on the percentage delta between WBRT and CRT.

Results

The WBRT group showed a negative large effect (d?=?? 0.922; p?=?0.0274) for the timed up and go, and a large effect for chair rise in 30″ and the elbow flex test (d?=?1.58; p?=?0.0012; d?=?2.8; p?=?0.01) respectively. Intervention comparisons based on the delta percentage between WBRT and CRT presented an intermediate effect (d?=?0.606; p?=?0.157) for the stair climb, a large effect (d?=?0.988; p?=?0.0282) for the timed up and go, and a large negative effect [d?=?? 1.32 (90.0% CI ? 1.92, ? 0.646); p?=?0.0038] for the elbow flex test. Concentric extensor-flexor peak torque (60°/s) showed an intermediate effect (d?=?0.749; p?=?0.0876; d?=?0.65; p?=?0.122 respectively). Body fat (%) demonstrated an intermediate effect (d?=?0.523; p?=?0.234).

Conclusion

WBRT with the concentric phase performed as fast as possible was able to improve physical functional capacity and maximal knee extension strength of older women.

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