Lack of known hepatitis virus in hepatitis-associated aplastic anemia and outcome after bone marrow transplantation

Viral infection has been shown to induce aplastic anemia, unidentified types of hepatitis being the most common cause for aplastic anemia-associated viral hepatitis. The survival rate for this group of patients after bone marrow transplantation with stem cells from an HLA-matched sibling is not well known. The aim of this study was to determine the prevalence of hepatitis G virus (HGV) and transfusion transmitted virus (TTV) infection in non-A, non-B, non-C hepatitis associated-aplastic anemia (HAAA) patients, and to define the role of bone marrow transplantation (BMT) as a therapeutic modality for this disease. Sixty-eight patients (43 males and 25 females) with aplastic anemia, underwent allogeneic BMT at the Hadassah University Hospital between 1981 and 1997. Onset of hepatitis was defined as jaundice and elevated alanine aminotransaminase (ALT) levels. Onset of aplastic anemia was defined as the first date on which varying degrees of pancytopenia occurred: hemoglobin level below 10 g/dl, WBC below 2 x 10(9)/l and low platelet count 10 x 10(10)/l. Serial serum samples from HAAA patients were assayed for virological and/or serological markers of hepatitis A, B, C, D, E, G viruses, TTV and parvovirus B19. Seventeen of the 68 patients with aplastic anemia (25%) suffered from hepatitis, 12 males and five females, ages 5 to 36 years. The mean interval between onset of hepatitis and first indication of aplastic anemia was 62 days (range 14-225 days). The development of aplastic anemia was unrelated to age, sex or severity of hepatitis. Ten of the 17 patients (59%) achieved complete ALT recovery prior to the diagnosis of aplastic anemia. Serum samples were available for 15 patients; none had evidence of acute or active hepatitis A, B, C, D, E, G and TTV virus infection at the time of diagnosis. Parvovirus B19 DNA sequences were not detectable in 10 of 12 tested cases; two positive results were detected in serum samples obtained after blood transfusion, making the analysis of these positive results difficult. All 17 patients underwent BMT. The mean post-BMT follow-up period was 38 months (range 1 day-123 months), five patients (30%) died 1 to 160 days post BMT, and 12 (70%) are alive 31 to 123 months after BMT. Relapsing hepatitis was not observed in any of the patients. In conclusion, HAAA is a disease of the young and the etiologic agent associated with HAAA remains unknown. HGV, TTV and parvovirus B19 sequences were not detected in any of the HAAA cases. The survival rate after BMT with stem cells from an HLA-matched sibling is similar to that for patients with non-hepatitis-associated aplastic anemia.

Exploration of mixed-valence chemistry: inventing new analogues of the Creutz-Taube ion

Starting from the Creutz-Taube ion as the prototype of a molecule-bridged mixed-valent complex, a number of related systems are presented in which the metal, the co-ligands, the molecular bridge, the d electron configuration, the medium, the charge, the coordination mode, or the nuclearity have been modified. The new mixed-valent configurations, as obtained through various chemical approaches, display different stabilities and spectroscopic characteristics in relation to the Creutz-Taube ion; the analysis of these results serves to provide a better understanding of fundamental aspects of molecule-mediated metal-metal interaction.

[Ultrasound anatomy of the sciatic nerve of the thigh]

Ultrasound examinations of the sciatic nerve were performed using high-resolution transducers (7.5, 10 to 20 MHz) both in anatomical specimens and in healthy volunteers. The ultrasonographic anatomy (sono-anatomy) of the nerve, its course along the thigh and its echogenicity in comparison with muscles, tendons and adipose tissue were investigated in 10 isolated muscle/nerve preparations. In addition, the influence of the angle of the applied transducer on the various different tissues was evaluated. In the clinical part of the study, the sciatic nerve was identified ultrasonographically in both thighs of 50 sex-matched healthy volunteers aged between 2 and 76 years. The normal sciatic nerve presents as a tubular echogenic structure with parallel linear internal echoes in the longitudinal section, and as a punctiform moderately echoic structure in cross-section, with the perineurium producing bright boundary echoes. Varying the insonating angle of the transducer reduced echogenicity, but to a smaller degree than in muscles and tendons. Unequivocal identified of the sciatic nerve from the level of the gluteal fold to its bifurcation in the distal thigh was possible in all but one case. We conclude that the course of the sciatic nerve along the thigh can be reliably identified and imaged with high-resolution ultrasound.

Conversion of the central [4Fe-4S] cluster into a [3Fe-4S] cluster leads to reduced hydrogen-uptake activity of the F420-reducing hydrogenase of Methanococcus voltae

As in many other hydrogenases, the small subunit of the F420-reducing hydrogenase of Methanococcus voltae contains three iron-sulfur clusters. The arrangement of the three [4Fe-4S] clusters corresponds to the arrangement of [Fe-S] clusters in the [NiFeSe] hydrogenase of Desulfomicrobium baculatum. Many other hydrogenases contain two [4Fe-4S] clusters and one [3Fe-4S] cluster with a relatively high redox potential, which is located in the central position between a proximal and a distal [4Fe-4S] cluster. We have investigated the role of the central [4Fe-4S] cluster in M. voltae with regard to its effect on the enzyme activity and its spectroscopic properties. Using site-directed mutagenesis, we constructed a strain in which one cysteine ligand of the central [4Fe-4S] cluster was replaced by proline. The mutant protein was purified, and the [4Fe-4S] to [3Fe-4S] cluster conversion was confirmed by EPR spectroscopy. The conversion resulted in an increase in the redox potential of the [3Fe-4S] cluster by about 400 mV. The [NiFe] active site was not affected significantly by the mutation as assessed by the unchanged Ni EPR spectrum. The specific activity of the mutated enzyme did not show any significant differences with the artificial electron acceptor benzyl viologen, but its specific activity with the natural electron acceptor F420 decreased tenfold.

Influence of the fusion of two subunits of the F420-non-reducing hydrogenase of Methanococcus voltae on its biochemical properties

In Methanococcus voltae, one of the two [NiFeSe] hydrogenases is unusual in that the large subunit is split into two subunits, each contributing two ligands to the [NiFe] center that catalyzes the heterolytic cleavage of the dihydrogen molecule. We have engineered a fusion of these two subunits. The resulting new enzyme showed no significant difference in hydrogen uptake activity or in the Ni-C or Ni-L EPR spectra compared to the the wild-type enzyme, but exhibited a tenfold increase in both the Km for hydrogen and the Ki for the competitive inhibitor carbon monoxide.

Extraction and amplification of authentic DNA from ancient human remains

A total of 36 ancient human remains from 12 individuals (three tooth/bone samples each) and one sample each of three individuals from the newest time was typed in a blind study using the amelogenin sex test. Prior to this molecular sex determination the sex of the individual was determined morphologically. The success rate of the amelogenin amplifications was >90%. For every individual an unambiguous molecular sex typing result was obtained. Furthermore, the morphological and molecular sex determinations were in accordance with each other, giving evidence for the authenticity and ancient origin of the polymerase chain reaction (PCR) amplifications.

Detection of tumor circulating cells by cytokeratin 20 in the blood of patients with endometrial carcinoma

BACKGROUND

Cytokeratins are constituents of the intermediate filaments of epithelial cells which are expressed in various combinations depending on the epithelial type and the degree of differentiation. Using the reverse transcriptase-polymerase chain reaction technique (RT-PCR) we recently demonstrated that: (1) Cytokertin 20-the most recent discovered cytokeratin-is expressed in endometrial carcinoma tumors but not in the endometrium of patients with benign diseases, and (2) CK-20 is not expressed in blood cells. The aim of this study is to examine whether CK-20 expression in blood can be used as a biomarker for the detection of the dissemination of malignant cells in patients treated for endometrial carcinoma.

METHODS

In the present study, we have used RT-PCR to determine the expression of CK-20 in the peripheral blood of the following groups: (1) preop new diagnosed patients (n = 20), (2) patients with no clinical evidence of disease following completion of definitive treatment (n = 33; 17 at low risk; 16 at high risk), (3) patients with recurrent disease (n = 6), and (4) a control group of healthy subjects (n = 16). RNA was extracted from cell pellets and analysed by RT-PCR using primers for CK-20.

RESULTS

Of the 20 patients of the first group 7 (35%) were CK-20 positive. Of the 33 patients of the second group 17 (51%) were CK-20 positive. Subdivision of this group showed that 9 of 17 (53%) were positive in the low-risk subgroup, and 8 of 16 (50%) were positive in the high-risk subgroup. All 6 patients with recurrent disease were positive, and all subjects in the control group were negative.

CONCLUSION

These results indicate that RT-PCR of CK-20, because of its high sensitivity, is a potential biomarker for detecting metastasis in blood samples of patients with endometrial carcinoma.

[Candida endophthalmitis in drug abuse. case report

BACKGROUND

Endogenous fungal endophthalmitis is mostly seen as opportunistic infection, particularly in immunocompromised patients and under special risk factors. The therapeutical approach and the value of vitrectomy in diagnosis and therapy are discussed.

PATIENT

A 42-years-old intravenous heroin addicted male patient with unilateral Candida albicans endophthalmitis, determined by cultivation is presented. The visual acuity at initial was 20/25 but decreased to hand-movements within 14 days despite systemic therapy. Treatment with systemic Fluconazole was extended and vitrectomy performed. The infection resolved but left a scar in the macula. The patient recovered a visual acuity of 20/80.

CONCLUSION

Candida albicans endophthalmitis is a dreaded situation in ophthalmology. It has poor visual prognosis if left untreated. Therefore immediate diagnosis and aggressive therapy, if necessary vitrectomy are required.

Regional diastolic function by pulsed Doppler myocardial mapping for the detection of left ventricular ischemia during pharmacologic stress testing: a comparison with stress echocardiography and perfusion scintigraphy

OBJECTIVES

We evaluated regional diastolic function by pulsed Doppler myocardial mapping for the detection of left ventricular ischemia during pharmacologic stress testing.

BACKGROUND

Evaluation and quantification of diastolic myocardial function remain a challenge for imaging techniques in stress tests.

METHODS

A prospective study compared the detection of coronary artery stenosis: 1) by pulsed Doppler myocardial mapping, 2) by two-dimensional echocardiographic dobutamine stress test, and 3) by perfusion scintigraphy in 64 patients using coronary angiography for reference. An age matched subgroup of 10 patients with normal angiograms and two-dimensional echocardiographic stress test served as control group. Peak myocardial contraction velocity (Vc) and lengthening rate during early diastolic left ventricular (LV) filling (VE) were measured in 12 LV segments from three apical views.

RESULTS

In controls, myocardial velocities increased during stress by > or =3.6 cm/s (p < 0.001). In LV segments depending on a stenosed artery (n = 70), VE decreased by > or =1 cm/s and, thus, was different from control segments (n = 112, p < 0.001) and from scar segments (n = 13, p < 0.01), whereas the change of Vc was similar to that in scar segments. A stress induced 2 cm/s reduction of VE discerned the best diagnostic accuracy (sensitivity 84%, specificity 93%) in comparison with two-dimensional echocardiography (78% and 71%) and perfusion scintigraphy (61% and 86%). Using receiver operating curves at incremental levels of luminal narrowing, these relations persisted.

CONCLUSIONS

Quantification of diastolic myocardial function by pulsed Doppler myocardial mapping during dobutamine stress test was shown to be a feasible, accurate, reproducible, noninvasive technique that should be considered to be a sensitive alternative to the present echocardiographic and scintigraphic imaging techniques for stress tests.

Characterization of two alpha-galactosidase mutants (Q279E and R301Q) found in an atypical variant of Fabry disease

The mutant products Q279E ((279)Gln to Glu) and R301Q ((301)Arg to Gln) of the X-chromosomal inherited alpha-galactosidase (EC 3.2.1. 22) gene, found in unrelated male patients with variant Fabry disease (late-onset cardiac form) were characterized. In contrast to patients with classic Fabry disease, who have no detectable alpha-galactosidase activity, atypical variants have residual enzyme activity. First, the properties of insect cell-derived recombinant enzymes were studied. The K(m) and V(max) values of Q279E, R301Q, and wild-type alpha-galactosidase toward an artificial substrate, 4-methylumbelliferyl-alpha-D-galactopyranoside, were almost the same. In order to mimic intralysosomal conditions, the degradation of the natural substrate, globotriaosylceramide, by the alpha-galactosidases was analyzed in a detergent-free-liposomal system, in the presence of sphingolipid activator protein B (SAP-B, saposin B). Kinetic analysis revealed that there was no difference in the degradative activity between the mutants and wild-type alpha-galactosidase activity toward the natural substrate. Then, immunotitration studies were carried out to determine the amounts of the mutant gene products naturally occurring in cells. Cultured lymphoblasts, L-57 (Q279E) and L-148 (R301Q), from patients with variant Fabry disease, and L-20 (wild-type) from a normal subject were used. The 50% precipitation doses were 7% (L-57) and 10% (L-148) of that for normal lymphoblast L-20, respectively. The residual alpha-galactosidase activity was 3 and 5% of the normal level in L-57 and L-148, respectively. The quantities of immuno cross-reacting materials roughly correlated with the residual alpha-galactosidase activities in lymphoblast cells from the patients. Compared to normal control cells, fibroblast cells from a patient with variant Fabry disease, Q279E mutation, secreted only small amounts of alpha-galactosidase activity even in the presence of 10 mM NH(4)Cl. It is concluded that Q279E and R301Q substitutions do not significantly affect the enzymatic activity, but the mutant protein levels are decreased presumably in the ER of the cells.

Laparoscopic live donor nephrectomy: the recipient

BACKGROUND

Laparoscopic live donor nephrectomy offers advantages to the donor in terms of decreased pain and shorter recuperation. Heretofore no detailed analysis of the recipient of laparoscopically procured kidneys has been performed. The purpose of this study was to determine whether laparoscopic donor nephrectomy had any deleterious effect on the recipient.

METHODS

A retrospective review was conducted of all live donor renal transplantations performed from January 1995 through April 1998. The control group received kidneys procured via a standard flank approach (Open). Rejection was diagnosed histologically. Creatinine clearance was calculated using the Cockroft-Gault formula.

RESULTS

A total of 110 patients received kidneys from laparoscopic (Lap) and 48 from open donors. One-year recipient (100% vs. 97.0%) and graft (93.5% vs. 91.1%) survival rates were similar for the Open and Lap groups, respectively. A similar incidence of vascular thrombosis (3.4% vs. 2.1%, P=NS) and ureteral complications (9.1% vs. 6.3%, P=NS) were seen in the Lap and Open groups, respectively. The incidence of acute rejection for the first month was 30.1% for the Lap group and 31.9% for the Open group (P=NS). The rate of decline of serum creatinine level in the early posttransplantation period was initially greater in the Open group, but by postoperative day 4 no significant difference existed. No difference was observed in allograft function long-term. The median length of hospital stay was 7.0 days for both groups.

CONCLUSIONS

Laparoscopic live donor nephrectomy does not adversely effect recipient outcome. The previously demonstrated benefits to the donor, and the increased willingness of individuals to undergo live kidney donation, coupled with the acceptable outcomes experienced by recipients of laparoscopically procured kidneys justifies the continued development and adoption of this operation.

Electron paramagnetic resonance and spectroscopic characteristics of electrogenerated mixed-valent systems [(eta 5-C5Me5)M(mu-L)M(eta 5-C5Me5)]+ (M = Rh, Ir; L = 2,5-diiminopyrazines) in relation to the radicals [(eta 5-C5Me5)ClM(mu-L)MCl(eta 5-C5Me5)]+ and [(eta 5-C5Me5)M(mu-L)MCl(eta 5-C5Me5)]2+

Electrochemical reduction of the dinuclear [(eta 5-C5Me5)ClM(mu-L)MCl(eta 5-C5Me5)]2+ ions (M = Rh, Ir; L = 2,5-bis(1-phenyliminoethyl)pyrazine (bpip) and 2,5-bis[1-(2,6-dimethylphenyl)iminoethyl]pyrazine (bxip)) proceeds via the paramagnetic intermediates [(eta 5-C5Me5)ClM(mu-L)MCl(eta 5-C5Me5)]+ (L = bpip) or [(eta 5-C5Me5)M(mu-L)MCl(eta 5-C5Me5)]2+ (L = bxip) and [(eta 5-C5Me5)M(mu-L)M(eta 5-C5Me5)]+. Whereas the first is clearly a radical species with a small g anisotropy, the chloride-free cations are distinguished by structured intervalence charge transfer (IVCT) bands in the near-infrared region and by rhombic electron paramagnetic resonance features between g = 1.9 and g = 2.3, which suggests considerable metal participation at the singly occupied MO. Alternatives for the d configuration assignment and for the role of the bisbidentate-conjugated bridging ligands will be discussed. The main difference between bpip and bxip systems is the destabilization of the chloride-containing forms through the bxip ligand for reasons of steric interference.

Detection of micrometastasis by cytokeratin-20 (reverse transcription polymerase chain reaction) in lymph nodes of patients with endometrial cancer

BACKGROUND

Cytokeratins are constituents of the intermediate filaments (IFs) of epithelial cells which are expressed in various combinations, depending on the type of epithelium and degree of differentiation. We have reported (R. Zemer, A. Fishman, J. Bernheim, S. Zimlichman, O. Markowitz, M. Altaras, and A. Klein, Gynecol Oncol 70:410-413, 1998) on the determination of cytokeratin-20 (CK-20) by reverse transcription polymerase chain reaction (RT-PCR) in the detection of endometrial cancer cells as a potential biomarker. In that study, we also found that by using immunocytochemistry, most carcinomas were found to be negative for CK-20. The sensitivity and specificity rates obtained by using the RT-PCR method were 94.4 and 91%, respectively.

OBJECTIVE

The aim of this study is to investigate the feasibility and potential of the specific mRNA marker, CK-20, to detect endometrial cancer cells-micrometastases (MMs)-by RT-PCR in lymph node (LN) samplings of patients undergoing hysterectomy for endometrial carcinoma.

METHOD

We used the RT-PCR method to determine the expression of CK-20 in the LNs of 20 patients [study group (SG)] who were being surgically staged and treated for endometrial carcinoma. The specificity of the mRNA CK-20 marker was examined in LNs obtained from five healthy patients [control group (CG)] who underwent abdominal hysterectomy and bilateral salpingo-oopherectomy for benign gynecologic conditions. The LNs obtained from the SG and CG patients were prepared together before mRNA extraction. RNA of the various cell pellets was extracted and RT-PCR was performed with CK-20 primers. RT-PCR products were analyzed by agarose gel electrophoresis and ethidium bromide staining against PCR size markers. Specificity of the RT-PCR products was examined by Southern blotting.

RESULTS

Histopathologic examinations demonstrated the presence of metastases in two (10%) SG patients. These patients were also CK-20 positive. Of the remaining 18 patients with negative histopathologic results, 6 (33%) were CK-20 positive and 12 (67%) were negative. All the CG patients were CK-20 negative (specificity, 100%).

CONCLUSIONS

The results obtained in this study suggest that RT-PCR of CK-20 is more sensitive than traditional histopathologic methods in the diagnosis of MMs in LNs of patients with endometrial cancer. Thus, due to the aforementioned characteristics of CK-20, it may be considered a powerful biomarker in the detection of MMs in LNs of patients with endometrial cancer.