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1.
OBJECTIVES: 1) To assess, with a peripheral magnetic resonance imaging system (pMRI), the prevalence of bony and soft tissue abnormalities in the knee joints of normal subjects, osteoarthritis (OA) patients, and individuals who have suffered an anterior cruciate ligament (ACL) rupture; and 2) to compare the prevalence among groups. METHODS: Magnetic resonance (MR) images of 28 healthy, 32 OA, and 26 ACL damaged knees were acquired with a 1.0-T pMRI system. Two radiologists graded the presence and severity of 9 MR image features: cartilage degeneration, osteophytes, subchondral cyst, bone marrow edema, meniscal abnormality, ligament integrity, loose bodies, popliteal cysts, and joint effusion. RESULTS: Ten of 28 healthy (35.7%), 24 of 26 ACL (92.3%), and all OA knees (100%) showed prevalent cartilage defects; 5 healthy (17.9%), 20 ACL (76.9%), and all OA knees (100%) had osteophytes; and 9 normal (32.1%), 21 ACL (80.8%), and 29 OA knees (90.6%) had meniscal abnormalities. One-half of the knees in the OA group (16 of 32, 50%) had subchondral cysts, and almost one-half had bone marrow edema (15 of 32, 46.9%). These features were not common in the ACL group (7.7%, and 11.5%, respectively) and were not observed in healthy knees. The OA group had the most severe cartilage defects, osteophytes, bone marrow edema, subchondral cysts, and meniscal abnormalities; the ACL group showed more severe cartilage defects, osteophytes, and meniscal abnormalities than did normal subjects. CONCLUSION: The results suggest that knees that have sustained ACL damage have OA-like reatures; most subjects (19 of 26, 73.1%) could be identified as in the early stage of OA. The prominent abnormalities present in ACL-damaged knees are cartilage defects, osteophytes, and meniscal abnormalities.  相似文献   
2.
MaxiK channel partners: physiological impact   总被引:7,自引:2,他引:7  
The basic functional unit of the large-conductance, voltage- and Ca2+-activated K+ (MaxiK, BK, BKCa) channel is a tetramer of the pore-forming α-subunit (MaxiKα) encoded by a single gene, Slo , holding multiple alternative exons. Depending on the tissue, MaxiKα can associate with modulatory β-subunits (β1–β4) increasing its functional diversity. As MaxiK senses and regulates membrane voltage and intracellular Ca2+, it links cell excitability with cell signalling and metabolism. Thus, MaxiK is a key regulator of vital body functions, like blood flow, uresis, immunity and neurotransmission. Epilepsy with paroxysmal dyskinesia syndrome has been recognized as a MaxiKα-related disorder caused by a gain-of-function C-terminus mutation. This channel region is also emerging as a key recognition module containing sequences for MaxiKα interaction with its surrounding signalling partners, and its targeting to cell-specific microdomains. The growing list of interacting proteins highlights the possibility that associations with the C-terminus of MaxiKα are dynamic and depending on each cellular environment. We speculate that the molecular multiplicity of the C-terminus (and intracellular loops) dictated by alternative exons may modulate or create additional interacting sites in a tissue-specific manner. A challenge is the dissection of MaxiK macromolecular signalling complexes in different tissues and their temporal association/dissociation according to the stimulus.  相似文献   
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4.

Background:

Infection with Trichostrongylus spp. is common among human and herbivorous in most parts of Iran, especially in southern and northern areas. The aim of present study was to identify Trichostrongylus spp. among human population using excreted egg specimens, by the molecular method, in Mazandaran Province, northern Iran.

Methods:

Overall, 33 positive fecal specimens were randomly sampled and examined. PCR amplification of ITS2-rDNA region was performed on the isolated egg and then a restriction fragment length polymorphism (RFLP) profile was considered to discriminate of Trichostrongylus spp.

Results:

A total of 33 positive fecal specimens, 29(78.9%), 4(12.1%) were found T. colubriformis and T. axei respectively. Our data appear the molecular evidence of both human T. colubriformis and T. axei infections in North of Iran.

Conclusion:

T. colubriformis was the probable most common zoonotic species causing human trichostrongylosis infection in the area  相似文献   
5.
Journal of Clinical Monitoring and Computing - Comparison of two depth of anesthesia indices, qCON (Conox) and PSI (Sedline), during desflurane sedation and their sensitivity to random ketamine...  相似文献   
6.
BackgroundReversible Cerebral Vasoconstriction Syndrome is a condition of transient cerebral vascular spasms, which usually presents with recurrent thunderclap headaches and recovers within 3 months. Several probable triggers and underlying factors, such as sex hormones, vasoactive drugs, head trauma or surgery, and tumors, have been implicated.Case presentationIn this paper, we present a 53-year-old woman with thunderclap headaches and normal lab tests who was radio-clinically diagnosed with reversible cerebral vasoconstriction syndrome and treated accordingly. Then, she experienced the recurrence of RCVS after about 2 years and headaches after 1 year in association with high blood pressure, high blood sugar, hypothyroidism, hyperlipidemia, and a urine metanephrine level of 5 times higher than the normal limit, suggesting a diagnosis of pheochromocytoma. After confirmation of the diagnosis with further imaging studies, surgical removal of the tumor resolved all the signs and symptoms.ConclusionOften underdiagnosed, pheochromocytoma could be an important condition associated with RCVS. It is important for clinicians to bear this diagnosis in mind while dealing with similar cases of recurrent thunderclap headaches.  相似文献   
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8.
BackgroundCurrently, an anteroposterior radiograph of the knee is judged based on a centered position of the patella between the femoral condyles. We are not aware of any anatomic literature supporting this recommendation.Questions/PurposesOrthogonal images are required for accurate assessment of knee deformity. Although an image with the patella centered at the distal femur is generally accepted as a true anteroposterior (AP) radiograph of the knee, there is minimal anatomic data to support that this view is orthogonal to a true lateral view of the knee where the condyles are overlapped. We designed an anatomical study to test the relationship between these two radiographic views.MethodsWe studied 428 well-preserved cadaveric skeletons ranging from 40 to 79 years of age at death. Centering of the patella was calculated based on distal femoral and patellar widths. Multiple regression analysis was then performed to determine the relationship between patellar centering and age, gender, ethnicity, mechanical lateral distal femoral angle (mLDFA), medial proximal tibial angle (MPTA), femoral anteversion, and contralateral centering.ResultsAverage patellar centering was 0.13 ± 0.04, indicating that the average patella was laterally positioned in the distal femur. Only mLDFA and contralateral centering showed statistically significant independent correlations with patellar centering with modest standardized beta coefficients of 0.10 and 0.23, respectively.ConclusionsIn the average specimen, the patella is laterally deviated by 13% of the condylar width. Clinicians should be aware that a lateral view with the femoral condyles overlapped is not always orthogonal to a patella-centered AP view when planning and implementing deformity correction.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-014-9419-3) contains supplementary material, which is available to authorized users.  相似文献   
9.
Pretreatment with a phytoestrogen genistein has been shown to attenuate the development of pulmonary hypertension (PH). Because PH is not always diagnosed early, we examined whether genistein could also reverse preexisting established PH and prevent associated right heart failure (RHF). PH was induced in male rats by 60 mg/kg of monocrotaline. After 21 days, when PH was well established, rats received daily injection of genistein (1 mg/kg per day) for 10 days or were left untreated to develop RHF by day 30. Effects of genistein on human pulmonary artery smooth muscle cell and endothelial cell proliferation and neonatal rat ventricular myocyte hypertrophy were assessed in vitro. Severe PH was evident 21 days after monocrotaline, as peak systolic right ventricular pressure increased to 66.35±1.03 mm Hg and right ventricular ejection fraction reduced to 41.99±1.27%. PH progressed to RHF by day 30 (right ventricular pressure, 72.41±1.87 mm Hg; RV ejection fraction, 29.25±0.88%), and mortality was ≈75% in RHF rats. Genistein therapy resulted in significant improvement in lung and heart function as right ventricular pressure was significantly reduced to 43.34±4.08 mm Hg and right ventricular ejection fraction was fully restored to 65.67±1.08% similar to control. Genistein reversed PH-induced pulmonary vascular remodeling in vivo and inhibited human pulmonary artery smooth muscle cell proliferation by ≈50% in vitro likely through estrogen receptor-β. Genistein also reversed right ventricular hypertrophy (right ventricular hypertrophy index, 0.35±0.029 versus 0.70±0.080 in RHF), inhibited neonatal rat ventricular myocyte hypertrophy, and restored PH-induced loss of capillaries in the right ventricle. These improvements in cardiopulmonary function and structure resulted in 100% survival by day 30. Genistein restored PH-induced downregulation of estrogen receptor-β expression in the right ventricle and lung. In conclusion, genistein therapy not only rescues preexisting severe PH but also prevents the progression of severe PH to RHF.  相似文献   
10.
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