מחקרים קליניים במחלות פנימיות שונות
מחקר קליני בנושאים שונים ברפואה פנימית ניתן למצוא ברשימת המאמרים המלאה, במאמרים הבאים: 1, 2, 15, 45, 54, 56, 69, 70, 73, 108, 147, 174, 207, 228, 256, 259, 267, 270, 300, 330, 335, 359, 365, 379, 380, 398, 411, 430, 470, 471, 490, 504 (לרשימת המאמרים המלאה). להלן, מובאים תקצירים של 5 מאמרים נבחרים:
Am J Hum Genet. 2003 Feb;72(2):375-83.
Cold-induced sweating syndrome is caused by mutations in the CRLF1 gene.
Knappskog PM, Majewski J, Livneh A, Nilsen PT, Bringsli JS, Ott J, Boman H.
In 1978, Sohar et al. described a strikingly peculiar syndrome in two Israeli sisters. These young women responded to environmental temperatures of 18 degrees C-7 degrees C with profuse sweating on large segments on their back and chest. Both had additional abnormalities, including a high-arched palate, nasal voice, depressed nasal bridge, inability to fully extend their elbows, and kyphoscoliosis. We have observed this disorder in two Norwegian brothers. Genome-wide screening in the two families, followed by saturation marker studies and linkage analysis, identified a 1.4-Mb homozygous candidate region on
chromosome 19p12. The maximum multipoint LOD score was 4.22. In both families, DNA sequencing of 25 genes within the candidate region identified potentially deleterious CRLF1 sequence variants that were not found in unaffected control individuals. Our findings confirm that the cold-induced sweating syndrome is an autosomal recessive disorder that is probably caused by impaired function of the CRLF1 gene, and they suggest important developmental functions for human CRLF1.
Am J Gastroenterol. 2003 Jul;98(7):1471-9.
Cholesterol crystal embolization to the digestive system: characterization of a common, yet overlooked presentation of atheroembolism.
Ben-Horin S, Bardan E, Barshack I, Zaks N, Livneh A.
In the 1359 published patients with multiorgan cholesterol crystal embolism (CCE), the digestive system seems to be the third most frequently affected system. Yet, this system received hitherto only little attention in the medical literature. Therefore, the aim of the present study was to clinically characterize the subset of patients with CCE involving the digestive system, based on our institutional experience and a review of the literature. Cases with CCE in a 7-yr period (1995-2001) were sought in the computerized records of our medical center. Of the CCE patients, those with digestive system involvement that could be related to CCE were included in this study. The clinical features of CCE were determined and compared with those found in published series. Fourteen cases with CCE were identified, giving an annual incidence of 0.8 per 10(5). Digestive system involvement was found in five (36%) of the 14 patients. All five patients had established atherosclerosis. Precipitating factors were vascular manipulations or anticoagulation treatment in four of these five patients. Two patterns of disease appeared: acute catastrophic multiorgan disorder with poor prognosis and chronic and more indolent GI disease. Abdominal pain, GI bleeding,
fever, and diarrhea were the most common manifestations, resulting from bowel infarction, mucosal ulcerations, hepatocellular liver disorder, and/or pancreatitis. CCE is a systemic disorder with a frequent involvement of the digestive system and protean clinical manifestations. It should, therefore, be considered in any gastroenterological patient with atherosclerosis and recent vascular manipulations or systemic anticoagulation.
Am J Med. 2005 Jun;118(6):636-40.
The composition of normal pericardial fluid and its implications for diagnosing pericardial effusions.
Ben-Horin S, Shinfeld A, Kachel E, Chetrit A, Livneh A.
BACKGROUND: Pericardial fluid obtained at pericardiocentesis is often subjected to biochemical and hematological analysis, and interpreted using criteria borrowed from pleural effusions. However, the validity and diagnostic yield of this approach is uncertain. Moreover, there is little data regarding the normal composition of the physiological pericardial fluid, which could serve as a reference for pathological effusions.
METHODS: Pericardial fluid from 30 patients undergoing elective open heart surgery was collected. Patients were excluded if they had known pericardial disease, had systemic disorders known to be associated with pericardial disease, or if the fluid samples were hemolytic. The biochemical and hematological parameters of the fluid were determined using standard laboratory techniques, and compared with the results obtained for concurrently drawn venous blood.
RESULTS: The median age of the study population was 64.5 +/- 10.6 years. Chemistry results of soluble molecules were consistent with the plasma ultrafiltrate nature of the fluid. However, fluid lactate dehydrogenase (LDH) level was unexpectedly high, averaging 2.4 times the serum level, and the mean protein level was 0.6 of the serum level. No correlation was found between comorbidities of patients and fluid characteristics. Fluids contained an average of 1430 leukocytes/muL, with a differential count that was predominated by lymphocytes (53.2 +/- 14%) and monocytes (11.6 +/- 6%).
CONCLUSIONS: The composition of the physiologic pericardial fluid is remarkable for high LDH and protein content, and for predominance of lymphocytes. Thus, the biochemical criteria useful for diagnosing pleural effusions are probably not applicable for differentiating transudative from exudative pericardial effusions, and lymphocytosis should be interpreted cautiously.
Medicine (Baltimore). 2006 Jan;85(1):49-53.
Large symptomatic pericardial effusion as the presentation of unrecognized cancer: a study in 173 consecutive patients undergoing pericardiocentesis.
Ben-Horin S, Bank I, Guetta V, Livneh A.
Large symptomatic pericardial effusion (PE)-PE that causes hemodynamic compromise-can be the initial presentation of an unrecognized underlying malignancy. However, the prevalence and features of this association have not been thoroughly characterized. We performed a retrospective study of all patients with hemodynamically significant PE who underwent pericardiocentesis in a 9-year period (1995-2004) in a tertiary hospital. Etiologies of pericardial disease were diagnosed using predetermined criteria. Demographic and clinical data of patients with hemodynamically significant PE as the presentation of their malignant disease were compared to those with established neoplastic disease, and to those
with other etiologies. We identified 173 patients who underwent pericardiocentesis during the study period. Neoplastic PE was found in 58 patients (33%), 45 of whom had a known malignant disease at the time of pericardiocentesis. Pericardial disease was found to be the presentation of an unrecognized underlying neoplastic disease, mostly a lung tumor, in 13 patients (7.5% of all etiologies). After exclusion of pericardial effusions with easily attributable causes by clinical circumstances, physical examination, and simple laboratory tests (traumatic, uremic, post-pericardiotomy, rheumatic, and effusions related to known neoplasia), newly found cancer accounted for 18% of the remaining 74 cases. No epidemiologic or clinical parameter was found useful to differentiate between cancerous and noncancerous effusions. In conclusion, a large symptomatic PE may be the presentation of an unrecognized underlying malignancy in approximately one-fifth of the patients with a nonrevealing basic workup. This grave diagnosis cannot be ruled out on the basis of any clinical parameter. Thus, a more extensive workup should probably be considered in this patient group.
J Immunol Methods. 2013 Apr 30;390(1-2):74-80.
Free light chain monomer-dimer patterns in the diagnosis of multiple sclerosis.
Kaplan B, Golderman S, Yahalom G, Yeskaraev R, Ziv T, Aizenbud BM, Sela BA, Livneh A.
In our search of new biomarkers for multiple sclerosis (MS), we aimed to characterize the immunoglobulin (Ig) free light chains (FLC) in patients' cerebrospinal fluid (CSF) and serum, and to evaluate the diagnostic utility of FLC monomer-dimer patterns for MS. FLC were analyzed by Western blotting and mass spectroscopy. CSF and serum samples were examined for the presence of oligoclonal Ig bands by a conventional laboratory test for MS. Three distinct pathological FLC monomer-dimer patterns, typical of MS but not of other neurological diseases, were revealed. In 31 out 56 MS patients the highly increased CSF levels of κ monomers and dimers were demonstrated. In 18 MS patients, the increased κ-FLC
levels were accompanied by highly elevated λ dimers. Five MS cases showed no significant elevation in κ-FLC, but they displayed abnormally high λ dimer levels. The intensity of the immunoreactive FLC bands was measured to account for κ and λ monomer and dimer levels and their ratios in the CSF and serum. Combined usage of different FLC parameters allowed the determination of the appropriate FLC threshold values to diagnose MS. The developed method showed higher sensitivity and specificity (96% and 90%, respectively), as compared to those of the conventional OCB test (82% and 70%, respectively). Our study highlights the
role of the differential analysis of monomeric and dimeric κ- and λ-FLC for the precise diagnosis of MS.