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81.
Serum osteocalcin (bone gla protein, BGP), a vitamin K-dependent non-collagenous bone protein and its relationship to other markers of bone and mineral metabolism were studied cross-sectionally in varying numbers of patients before and over 240 days following renal transplantation. Marked elevation of serum creatinine (11.9 +/- 0.76 mg/dl), osteocalcin (216.9 +/- 7 ng/ml), parathyroid hormone (PTH, mid-molecule fragment) (24.5 +/- 3.6 ng/ml), alkaline phosphatase (255.2 +/- 54.7 IU/l) and phosphorus (5.6 +/- 0.3 mg/dl) were noted preoperatively. Serum calcium levels remained normal throughout the study period while phosphate levels normalized within one week after transplantation. PTH levels progressively decreased postoperatively over the study period but were still elevated well above normal. Serum osteocalcin decreased to near normal values at 60-90 days after surgery. Both PTH and alkaline phosphatase correlated significantly with osteocalcin preoperatively and postoperatively. The relatively depressed values of osteocalcin in the face of still elevated PTH levels post-transplantation was attributed to the effect of immunosuppressive corticosteroid therapy. The significant correlation between PTH and osteocalcin suggests that osteocalcin may be as or more sensitive a measurement of bone turnover than alkaline phosphatase pre- and post-transplantation.  相似文献   
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Objective

To determine frequencies, interlaboratory reproducibility, clinical ratings, and prognostic implications of neural antibodies in a routine laboratory setting in patients with suspected neuropsychiatric autoimmune conditions.

Methods

Earliest available samples from 10,919 patients were tested for a broad panel of neural antibodies. Sera that reacted with leucine-rich glioma-inactivated protein 1 (LGI1), contactin-associated protein-2 (CASPR2), or the voltage-gated potassium channel (VGKC) complex were retested for LGI1 and CASPR2 antibodies by another laboratory. Physicians in charge of patients with positive antibody results retrospectively reported on clinical, treatment, and outcome parameters.

Results

Positive results were obtained for 576 patients (5.3%). Median disease duration was 6 months (interquartile range 0.6–46 months). In most patients, antibodies were detected both in CSF and serum. However, in 16 (28%) patients with N-methyl-d-aspartate receptor (NMDAR) antibodies, this diagnosis could be made only in cerebrospinal fluid (CSF). The two laboratories agreed largely on LGI1 and CASPR2 antibody diagnoses (κ = 0.95). The clinicians (413 responses, 71.7%) rated two-thirds of the antibody-positive patients as autoimmune. Antibodies against the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR), NMDAR (CSF or high serum titer), γ-aminobutyric acid-B receptor (GABABR), and LGI1 had ≥ 90% positive ratings, whereas antibodies against the glycine receptor, VGKC complex, or otherwise unspecified neuropil had ≤ 40% positive ratings. Of the patients with surface antibodies, 64% improved after ≥ 3 months, mostly with ≥ 1 immunotherapy intervention.

Conclusions

This novel approach starting from routine diagnostics in a dedicated laboratory provides reliable and useful results with therapeutic implications. Counseling should consider clinical presentation, demographic features, and antibody titers of the individual patient.

  相似文献   
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Background

Systemic sclerosis (SSc) is an autoimmune connective tissue disease with vascular, fibrotic and immune changes of skin and some internal organs. Anti-heterogeneous nuclear ribonucleoproteins (anti-hnRNP) were found in SSc patients.

Aim of the work

To assess anti-hnRNP A1 and A2 autoantibodies in limited SSc patients and to find their relation to clinical and hand radiographic characteristics.

Patients and methods

26 limited SSc patients and 16 matched control were studied. Skin thickness was scored according to the modified Rodnan skin score method (mRss) and radiologic examination by plain X-ray of the hand and wrist was performed anti-hnRNP A1 and A2 were measured in patients and control.

Results

All patients were females with a mean age of 37.5 ± 11.24 years and mean disease duration of 7.84 ± 1.19 years. 96.2% of cases showed juxta-articular osteoporosis, 38.5% with marginal erosions, 73.1% with surface erosions, 42.3% with subchondral cyst, 42.3% with metacarpophalangeal subluxation, 11.5% with marginal sclerosis, 80.8% with resorption of distal phalanges, 38.5% with resorption of distal ulna and 34.6% with calcinosis. Anti-hnRNPA1 was positive in all the patients but the anti-hnRNPA2 was positive in 21 (80.8%). Anti-hnRNP A1 and A2 showed significant difference between patients and control (5.66 ± 4.18 ng/ml vs 2.88 ± 0.82; p < 0.01 and 1.82 ± 0.36 vs 0.73 ± 0.08; p < 0.02, respectively). There was no significant correlation between the markers with the mRss or radiographic changes.

Conclusion

Joint affection in SSc is more frequent than expected. Anti-hnRNP A1 and anti hnRNP A2 antigens may be useful markers for SSc patient although no significant relation was found with radiologic findings.  相似文献   
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Objective Familial Mediterranean fever (FMF) is an autosomal recessive recurrent polyserositis with a higher prevalence in some ethnic groups, including Turks. Mutations in the FMF gene (MEFV) were found associated with FMF. The aim of this study was to analyze MEFV gene mutations in FMF patients to gain insight into the mutation phenotype correlation.Objectives We analyzed the most frequent mutations (M680I, M694V, V726A, and E148Q) in a group of young male Turkish FMF patients using an amplification refractory mutation system and a commercial kit.Results M694V mutation was detected in 80% of the patients. After making a strict diagnostic discrimination between arthralgia and arthritis, arthritis was present in 71% of homozygous and 29.4% of heterozygous patients for M694V mutation. Other mutations were not found to correlate with specific symptoms or findings.Conclusion The homozygosity of M694V mutation in the MEFV gene is associated with arthritis in FMF patients.  相似文献   
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BACKGROUND: The pathophysiologic mechanisms that determine the severity of Mediterranean spotted fever (MSF) and the host-related and microbe-related risk factors for a fatal outcome are incompletely understood. METHODS: This prospective study used univariate and multivariate analyses to determine the risk factors for a fatal outcome for 140 patients with Rickettsia conorii infection admitted to 13 Portuguese hospitals during 1994-2006 with documented identification of the rickettsial strain causing their infection. RESULTS: A total of 71 patients (51%) were infected with the Malish strain of Rickettsia conorii, and 69 (49%) were infected with the Israeli spotted fever (ISF) strain. Patients were admitted to the intensive care unit (40 [29%]), hospitalized as routine inpatients (95[67%]), or managed as outpatients (5[4%]). Death occurred in 29 adults (21%). A fatal outcome was significantly more likely for patients infected with the ISF strain, and alcoholism was a risk factor. The pathophysiology of a fatal outcome involved significantly greater incidence of petechial rash, gastrointestinal symptoms, obtundation and/or confusion, dehydration, tachypnea, hepatomegaly, leukocytosis, coagulopathy, azotemia, hyperbilirubinemia, and elevated levels of hepatic enzymes and creatine kinase. Some, but not all, of these findings were observed more often in ISF strain-infected patients. CONCLUSIONS: Although fatalities and similar clinical manifestations occurred among both groups of patients, the ISF strain was more virulent than the Malish strain. Multivariate analysis revealed that acute renal failure and hyperbilirubinemia were most strongly associated with a fatal outcome.  相似文献   
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Objective: The purpose of this study was to examine the vasoreactivity in retina and choroid of the healthy eyes in response to experimentally altered partial arterial pressure of carbon dioxide (PaCO2) using a non-invasive technique, spectral domain optical coherence tomography (SD-OCT).

Materials and methods: The study included non-smoking participants between 18 and 35 years of age, having visual acuity of 20/20 and with no systemic and ocular diseases. At baseline, the participants breathed room air (normocapnia). Hypocapnia was created with the help of hyperventilation; for this, the participants were instructed to draw deep and quick breaths, resulting one breathing cycle per 2?s. To create hypercapnia subjects rebreathed from a 5?l bag at least 3?min. Choroidal thickness and retinal artery diameter were measured at baseline, and hyperventilation and rebreathing conditions by SD-OCT.

Results: Twenty eyes of 20 healthy subjects were included in this study. Their mean age was 24.90?±?5.32 years. Hyperventilation caused a significant reduction in choroidal thickness, compared with baseline, at all points; whereas rebreathing caused no significant change at all points. The mean diameters of the arteries were 151.80?±?7.88?μm, with a significant decline to 148.90?±?7.25?μm at hyperventilation condition and a significant increase to 153.50?±?7.88?μm at rebreathing condition (p?=?0.018, p?=?0.043, respectively).

Conclusion: This study demonstrated that, SD-OCT was a useful tool in measuring the ocular vascular response under hypercapnia and hypocapnia conditions. These findings may be helpful for further understanding the physiological nature of ocular blood flow and this preliminary study provides a basis for future studies.  相似文献   
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