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Biomedical subjects

A Baram

Publications and source records attributed to A Baram.

At least 19 recordsLinked to original sources
PubMed2006

Analysis of the ordering transition of hard disks through the Mayer cluster expansion.

The available virial coefficients for the two-dimensional hard-disks model are transformed into a matrix representation of the thermodynamic potentials, which allows for an accurate description of the whole fluid phase, up to the phase transition. We find that the fluid phase terminates at the transition point, implying a second-order phase transition in accordance with the Kosterlitz-Thouless-Halperin-Nelson-Young scenario of a transition into a hexatic phase. The density and pressure at the transition are calculated from the available first ten virial coefficients, and are found to be in excellent agreement with recent Monte-Carlo calculations. Finally, we calculate the equation of state in the critical region.

Journal Article↗
PubMed2005

[Pleural endometriosis: an unusual presentation].

INTRODUCTION: Numerous conditions can produce chronic exudative pleural effusions. Pleural endometriosis is a rare cause of unilateral effusion with diffuse pleural thickening. CLINICAL CASE: We report the case of chronic pleural effusion in a thirty year old African woman, where pleural endometriosis was diagnosed only following pleuro-pulmonary decortication, with the diagnosis being confirmed by immunohistochemistry. CONCLUSION: Pleural endometriosis must be considered as a possible diagnosis in women with pleural effusions of unknown aetiology. The presence of endometrial glands or of chorionic cells within the pleura is characteristic. Immunohistochemistry is an important diagnostic tool.

Adult↗
PubMed2000

Do soluble cell adhesion molecules play a role in endometriosis?

PROBLEM: Endometriosis is a chronic inflammatory disease associated with diverse immunologic disturbances. Cell adhesion molecules are essential for the development of immune and inflammatory reactions. This study was conducted to investigate whether or not serum and peritoneal levels of soluble cell adhesion molecules are altered in women with endometriosis. METHOD OF STUDY: The study group comprised five women with moderate-to-severe endometriosis. Eight healthy women with a normal diagnostic laparoscopy served as controls. Serum and peritoneal fluid samples from both groups were analyzed for the soluble isoform of intercellular cell adhesion molecule-1 (sICAM-1). vascular cell adhesion molecule-1 (sVCAM-1), endothelial selectin (sES), and platelet selectin (sPS). RESULTS: Serum levels of sICAM-1 were significantly increased in women with endometriosis (median levels: 410.4 ng/mL; range: 233.9 ng/mL 598.4 ng/mL vs. 235.7 ng/mL; range: 187.4 ng/mL -323.7 ng/mL; P = 0.02). Although the levels of sVCAM-1, sES, and sPS in both samples were higher in the study group, the differences did not reach significance. CONCLUSIONS: Our results suggest a role of ICAM-1 in the pathophysiology of endometriosis. However. the role of other investigated cell adhesion molecules should be confirmed by further studies.

Adult↗
PubMed1999

Line narrowing of I = 12 spins coupled to quadrupolar nuclei in liquids: effects of weak decoupling fields

In this paper an exact description of the observed transverse magnetization of spin 12 nuclei, coupled to quadrupolar spins which are subjected to RF irradiation, is presented. It is shown that for on-resonance CW decoupling at weak to intermediate irradiation levels, the transverse decay of the spin 12 magnetization is modulated with a period of 1/nu(2), where nu(2) is the amplitude of the decoupling irradiation. When the spin 12 signal is created as a spin echo, and the quadrupolar resonance continuously irradiated during the echo evolution, the echo amplitudes experience much stronger modulation with period 2/nu(2). In previous treatments of such spin systems, the regime of weak decoupling power was usually neglected, and approximate analytical expressions seeking to define the "adequate" or "minimal" decoupling power, necessary to achieve the collapse of the spin 12 multiplet into a single narrow line, were derived. It is demonstrated here, both by experiments and by simulations using a full Redfield formalism, that simple analytical predictions for the T(2) decay of the spin 12 magnetization are still possible, even when the scalar relaxation is not in the "fast exchange" limit and the transverse decay is considerably modulated due to insufficient decoupling power. In this case, the expected single exponential decay rate is obtained for the nonmodulated component of the signal. The theoretical solution for spin I = 12 coupled to S = 3 is derived, and results for the proton decay in (10)B-enriched sodium borocaptate in aqueous solution are presented. The effects of irradiation by several composite pulse decoupling sequences are also considered. Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Levels of soluble vascular cell adhesion molecule-1 and soluble intercellular adhesion molecule-1 are increased in women with ovarian hyperstimulation syndrome.

OBJECTIVE: To determine whether plasma and peritoneal fluid levels of soluble vascular cell adhesion molecule-1 (sVCAM-1) and soluble intercellular adhesion molecule-1 (sICAM-1) are altered in women with ovarian hyperstimulation syndrome (OHSS). DESIGN: Prospective, case-control study. SETTING: Lis Maternity Hospital and the Sara Racine IVF Unit, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel. PATIENT(S): The study group comprised 16 women with severe OHSS. The control groups comprised 10 women treated with controlled ovarian hyperstimulation and 8 women with normal findings at diagnostic laparoscopy. INTERVENTION(S): Plasma samples were obtained from the study group and the first control group. Peritoneal fluid samples were obtained during paracentesis from the study group and during diagnostic laparoscopy from the second control group. MAIN OUTCOME MEASURE(S): Samples were assayed by specific ELISA for sVCAM-1 and sICAM-1. RESULT(S): The mean peritoneal fluid levels of sVCAM-1 and sICAM-1 and the mean plasma levels of sVCAM-1 were significantly higher in the women with OHSS than in the control groups. However, the mean plasma levels of sICAM-1 were comparable. A positive correlation was demonstrated between the levels of sVCAM-1 and plasma E2 at the time of hCG administration and between the levels of sICAM-1 and number of ova retrieved. CONCLUSION(S): Our findings suggest that soluble cell adhesion molecules may have a role in the pathogenesis and progression of OHSS.

Adult↗
PubMed1999

Decision-making in the colposcopy clinic--a critical analysis.

OBJECTIVE: To consider the omission of several diagnostic steps from the management of patients with high-grade squamous intraepithelial lesion (SIL) by analyzing the role of each step on the choice of treatment. STUDY DESIGN: Each diagnostic procedure was correlated to the treatment and outcome in 87 women with high-grade SIL. Treatments considered were large loop excision of the transformation zone (LLETZ) cold knife conization, and CO2 laser vaporization. RESULTS: Unsatisfactory colposcopy (P< or =0.01) and positive endocervical curettage (ECC) specimen (P< or =0.01) were essential for choice of treatment. CIN2 diagnoses of the preoperative cervical biopsy were rediagnosed as CIN3 based on the surgical specimen in 57% of the cases. The margins of 33 and 23% of surgical specimens removed by LLETZ or knife conization, respectively, displayed CIN involvement. Forty and 47% of these patients, respectively, later developed recurrent CIN. CONCLUSIONS: Omission of colposcopy and ECC could have resulted in sub-optimal treatment in many cases. Excision by LLETZ or knife conization is recommended for cases of CIN2 and CIN3. Follow up is imperative for patients with involvement of the margins.

Adult↗
PubMed1999

A selective increase in plasma soluble vascular cell adhesion molecule-1 levels in preeclampsia.

PROBLEM: The study was conducted to determine whether altered plasma levels of soluble intercellular adhesion molecule (ICAM)-1 and soluble vascular cell adhesion molecule (VCAM)-1 are involved in the pathogenesis of preeclampsia. METHOD OF STUDY: Maternal plasma samples were collected from 20 patients with preeclampsia, 20 matched normotensive patients with uncomplicated pregnancies. and ten healthy nonpregnant women. Samples were assayed for soluble VCAM-1 and soluble ICAM-1 by specific enzyme-linked immunosorbent assay. RESULTS: Both soluble VCAM-1 and soluble ICAM-1 were detectable in the plasma of all preeclamptic, normotensive pregnant, and nonpregnant women. The mean plasma level of soluble VCAM-1 was significantly higher in preeclamptic women compared to normotensive pregnant women (1831 ng/mL +/- 534 ng/mL vs. 1254 ng/mL +/- 386 ng/mL, respectively; P < 0.05). However, the plasma level of soluble VCAM-1 was unchanged during the third-trimester of normal pregnancy compared to nonpregnant women. The mean plasma level of soluble ICAM-1 in preeclamptic and normotensive pregnant women were increased when compared to nonpregnant women. However, the mean plasma level of soluble ICAM-1 was comparable in women with preeclampsia and normotensive pregnancy. CONCLUSIONS: The selective increased plasma levels of soluble VCAM-1 in patients with preeclampsia provide evidence for endothelial activation and suggest distinct pathways for neutrophil and endothelial activation in preeclampsia.

Adult↗
PubMed1998

Plasma soluble endothelial selectin is elevated in women with pre-eclampsia.

The study was conducted to determine whether altered plasma concentrations of soluble selectins are involved in the pathogenesis of pre-eclampsia. Maternal plasma samples were collected from 20 patients with pre-eclampsia, and from 20 matched normotensive patients with uncomplicated pregnancies. Samples were assayed for soluble endothelial selectin (sES), platelet selectin (sPS) and leukocyte selectin (sLS) by specific enzyme-linked immunosorbent assay. The three soluble selectins were detectable in the plasma of all pre-eclamptic and control patients. The mean plasma concentrations of sPS and sLS were comparable between the groups. However, the mean plasma concentration of sES was significantly higher in the pre-eclamptic group compared with the control group (61 ng/ml +/- 30 ng/ml compared with 40 ng/ml +/- 17 ng/ml; P < 0.01). The selective increased plasma concentrations of sES in patients with pre-eclampsia provide specific evidence for endothelial activation and may reflect distinct pathways for neutrophil activation in pre-eclampsia.

Adult↗
PubMed1998

Plasma interleukin-12 is elevated in patients with preeclampsia.

PROBLEM: Abnormal immune activation has been suggested as a contributor to the development of preeclampsia. We hypothesized that intact interleukin (IL)-12 directly, or through its main mediator, interferon (IFN)-gamma, contributes to the altered immune response observed in preeclampsia. METHOD OF STUDY: Plasma samples were collected from 20 patients with preeclampsia and 20 normotensive patients with uncomplicated pregnancies who were matched with the preeclamptic patients by age, gestational age, and parity. Samples were collected before the onset of labor, induction, or medical intervention. The samples were assayed for IL-12 and IFN-gamma by specific enzyme-linked immunoassays. RESULTS: IL-12 was detected in 35% of the preeclamptic patients and in 5% of the patients with normal pregnancies (P < 0.01). The detection rate and mean concentration of IFN-gamma were comparable in both groups. CONCLUSION: Intact plasma IL-12 is detected more frequently in preeclamptic patients, suggesting the involvement of this cytokine in the enhanced immune response observed in preeclampsia.

Adult↗
PubMed1997

Quadrupolar relaxation of spin 3 in the intermediate omega0tauc regime

The equations for the quadrupolar relaxation of spin 3 were derived for the Redfield limit where the molecular reorientation rate is much faster than the size of the quadrupolar interaction. In the extreme narrowing regime (omega0tauc << 1), the results converge to the analytical expressions for the relaxation rates available in the literature. For slower motions, both longitudinal (spin-lattice) and transverse (spin-spin) relaxations are described by a superposition of three exponentials, where both the rates themselves and their relative weights are functions of omega0tauc. Numerical calculations of the relevant relaxation parameters in the intermediate omega0tauc regime are presented. Spin-lattice relaxation is described to very good approximation by a single exponential for all values of omega0tauc, with the weight of the dominant decay mode exceeding 0. 97 for the entire range. The predictions of these simulations were found to be in good agreement with experimentally measured relaxation rates of the 10B resonances in the sodium salt of Na2B12H12S, mercaptoundecahydro-closo-dodecaborane (sodium borocaptate or BSH) dissolved in glycerol, determined at omega0 = 53. 73 MHz, between temperatures of 268 and 323 K. The fit to the experimental results yielded a value of 1.25 MHz for the average 10B quadrupolar coupling constant in this molecule. Copyright 1997 Academic Press. Copyright 1997Academic Press

Journal Article↗
PubMed1997

Vascular endothelial growth factor is increased in patients with preeclampsia.

PROBLEM: This study was conducted to determine whether altered levels of vascular endothelial growth factor (VEGF) may play a role in the pathogenesis of preeclampsia. METHOD OF STUDY: Maternal plasma samples were collected from 19 patients with preeclampsia (group A) either before the onset of labor, or before induction of labor or medical intervention. Plasma samples were also obtained from 19 normotensive patients with uncomplicated pregnancies (group B), who were matched with the patients with preeclampsia for gestational age and parity. Samples were frozen at -70 degrees C until assayed for VEGF by a specific enzyme-linked immunoassay. RESULTS: The mean maternal age was similar in groups A and B. For both groups the VEGF was detectable in all plasma samples. However, the plasma concentrations of VEGF were significantly increased in the group A patients, compared with those in group B (median, 47 ng/ml; range, 10.6-72 ng/ml versus median, 13.6 ng/ml; range, 0.66-20 ng/ml; P < 0.001). In group A, a positive correlation was noted between VEGF concentrations and the systolic and diastolic blood pressure (r = 0.56; P = 0.01 and r = 0.48; P = 0.037, respectively). CONCLUSIONS: Maternal plasma VEGF levels were elevated in the patients with preeclampsia and correlated with the severity of hypertension, suggesting a role for VEGF in the pathogenesis of preeclampsia.

Adult↗
PubMed1992

Differential expression of HPV types 6 and 11 in condylomas and cervical preneoplastic lesions.

Tumor biopsies from exophytic and flat condylomas at different locations on the genital epithelium (10 cases) and in cervical intraepithelial neoplasia (CIN) grades 1-2 (6 cases) were analysed for HPV types 6 and 11 DNA and RNA. The presence of mRNA species which could encode the E6, E7, E1M, E2, E2C, E4, E5 and L1 proteins was determined using the RNA polymerase chain reaction (PCR) technique with primers that flank previously mapped or predicted splice sites. The state of the viral DNA in the tumor biopsies was established by Southern blot analysis. We could detect the various mRNA species in biopsies from condylomas associated with both HPV types. The size of the RNA PCR products were in agreement with the previously mapped splice sites of mRNAs recovered from an experimental condyloma induced by HPV11. The major viral transcript encoding the E1i--E4 protein was detected in all the tumor biopsies. From the rare transcripts the rate of detection of mRNA species encoding the E1M, E2C proteins was the highest. In 2 of 6 CIN biopsies analysed only the major viral transcript was detected. The overall results of this study suggest that early gene products of HPV types 6 and 11 may be important in the induction of cellular proliferation and condylamatous differentiation but these possibly may not be required for the development of the HPV-associated cervical neoplasia.

Base Sequence↗
PubMed1992

Expression and splicing patterns of human papillomavirus type-16 mRNAs in pre-cancerous lesions and carcinomas of the cervix, in human keratinocytes immortalized by HPV 16, and in cell lines established from cervical cancers.

We have analysed the splicing patterns of human papillomavirus (HPV) type-16 mRNAs in a human epithelial cell line immortalized by HPV 16 (HPKII), in cell lines established from cervical carcinomas (SiHa and CaSki) and in pre-invasive and invasive carcinomas of the cervix. The presence of mRNA species previously described, which could encode the E6, E6I, E6II, E6III, E7, E2, E2C, E4, E5 and L1 proteins, was determined, using the RNA polymerase chain reaction (PCR) technique with primers that flank unique splice sites. The state of the viral DNA in the tumor biopsies was established by Southern blot analysis. The various HPV 16 transcripts could be detected in cell lines and in tumor biopsies. The size of the RNA PCR products were in agreement with the previously mapped splice sites. The full range of transcripts was revealed in the HPKII cell line and in a number of pre-invasive carcinomas. Messenger RNAs which could encode the E6III, E4 and E5 proteins were most prevalent in all types of tumor. The overall results of DNA and RNA analyses in cell lines and tumor specimens indicate that (1) expression of either of the early or late transcripts studied is not specifically related to (a) tumor stage or (b) the physical state of the viral genome; and (2) alterations in the splicing patterns of HPV 16 transcripts may not be involved in tumor progression.

Blotting, Southern↗
PubMed1985

Endometrial carcinoma stage I--comparison of two different treatment regimes--evaluation of risk factors and its influence on prognosis; suggested step by step treatment protocol.

Two hundred twenty-four patients with stage I endometrial carcinoma were treated between the years 1964 and 1978. One hundred and fifteen patients were classified as clinical stage Ia (51.3%) and 109 patients as clinical state Ib (48.7%). For stage Ia the standard treatment protocol was total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH + BSO). In stage Ib disease, preoperative irradiation was performed followed by TAH + BSO after an interval of 4 to 6 weeks. Postoperative irradiation to the pelvis and vaginal vault was given when extrauterine spread was found and in cases of myometrial penetration beyond the inner one-third of the myometrium. At evaluation in May 1983, the rate of disease recurrence in stage Ia was 20% and in stage Ib 9.1%. Five-year survival in stage Ia was 77.3% and 72.4% in stage Ib. Preoperative irradiation was found justified for G3 disregarding the clinical stage, therefore the approach of routine preoperative irradiation in stage Ib is not recommended. The uterine cavity depth was found to be an inaccurate prognostic parameter. According to the data collected in our material the histological grade and myometrial invasion are much better prognostic parameter and should be taken into consideration while planning the treatment regime.

Adenocarcinoma↗
PubMed1985

Population differences in ovarian cancer in Israel.

One hundred and seven patients with epithelial carcinoma of the ovaries were studied in an Israeli population in the Tel Aviv area. The women under study belonged mainly to two ethnic groups: European and North American (Ashkenazi) and Afro-Asian immigrants. The highest incidence of this neoplasm was found in the Ashkenazi group and the lowest in the Afro-Asian (less than 50%). It has been found that there is an age variation in the onset of the disease between the two ethnic groups. The average age of all the patients was 57 years, but in the Afro-Asian group of patients, the malignancy was more commonly found in the 45-54 age group (P less than 0.05). A tendency of a shorter survival rate due to more aggressive disease in the Afro-Asian group was observed. Survival rate for patients with FIGO stages I and II was lower in the Afro-Asian group. These conclusions were supported by the statistical significance of the data.

Adenocarcinoma↗