Expression of amoebapores is required for full expression of Entamoeba histolytica virulence in amebic liver abscess but is not necessary for the induction of inflammation or tissue damage in amebic colitis

Entamoeba histolytica trophozoites produce amoebapores, a family of small amphipathic peptides capable of insertion into bacterial or eukaryotic membranes and causing cellular lysis. Recently, E. histolytica trophozoites that are totally deficient in the production of amoebapore-A were created through a gene silencing mechanism (R. Bracha, Y. Nuchamowitz, and D. Mirelman, Eukaryot. Cell 2:295-305, 2003). Here we tested the virulence of amoebapore A(-) trophozoites in models of the two major forms of amebic disease: amebic liver abscess and amebic colitis. We demonstrate that amoebapore expression is required for full virulence in the SCID mouse model of amebic liver abscess, but E. histolytica trophozoites that do not express amoebapore-A can still cause inflammation and tissue damage in infected human colonic xenografts. These data are consistent with the concept that tissue damage may proceed by different mechanisms in amebic liver abscess compared to amebic colitis.     

Purification and characterization of placental heparanase and its expression by cultured cytotrophoblasts

The role of different extracellular matrix (ECM)-degrading enzymesin the normal functioning of the placenta is well documented.Heparan sulphate proteoglycan (HSPG) is an integral constituentof the placental and decidual ECM. Because this proteoglycanspecifically interacts with various macromolecules in the ECM,its degradation may disassemble the matrix. Hence, in the caseof the placenta, this may facilitate normal placentation andtrophoblast invasion. Crude placental specimens were collectedfrom first and third trimester placentas. Heparanase (endo-P-glucuronidase)was isolated and purified by ammonium sulphate precipitationfollowed by sequential chromatographies on carboxymethyl-, heparin-and ConA-Sepharose columns. The placental enzyme was furthercharacterized for its molecular weight and specific inhibitionby heparin, and was shown to resemble heparanase expressed byhighly metastatic tumour cells and activated cells of the immunesystem. In order to locate the source of heparanase activityin the placenta, primary cytotrophoblast cultures were established.Intact cells, as well as conditioned medium and cell lysates,were analysed for heparanase activity using metabolically sulphate-labelledECM as a natural substrate. Heparanase was highly active inlysates of cytotrophoblasts. This activity was also expressedby intact cytotrophoblasts seeded on ECM, but no activity couldbe detected in the culture medium. Incubation of the cytotrophoblastsin contact with ECM resulted in release of ECM-bound basic fibroblastgrowth factor (bFGF). We propose that the cytotrophoblasticheparanase facilitates placentation, through cytotrophoblastextravasation and localized neovascularization. cytotrophoblast/extracellular matrix/heparanase/heparan sulphate proteoglycan/placenta     

Ethnic ancestry and increased paternal age are risk factors for breast cancer before the age of 40 years.

To study the risk factors associated with breast cancer in women younger than 40 years, a cohort study (The Jerusalem Perinatal Study) of 42 822 female offspring born in hospitals in West Jerusalem during 1964-1976 was carried out. Hazard ratios of potential parental and perinatal risk factors for early breast cancer were measured. The overall incidence of breast cancer was 5.2/100 000 person-years. The highest incidence was found among Jewish women of West Asian ancestry (8.6/100 000 person-years), specifically those whose maternal grandfathers were born in Iraq, Iran or Afghanistan (9.5/100 000 person-years). Using Cox models we found independent risk factors for early breast cancer to be paternal age (relative risk/year=1.06, 95% confidence interval=1.02-1.10, P=0.005), and ancestry from Iraq/Iran/Afghanistan (relative risk=3.1, 95% confidence interval=1.50-6.52, P=0.002). The study confirms a previously observed effect of advanced paternal age on the occurrence of early breast cancer and identifies a novel population group at increased risk for the disease. The excess risk of early breast cancer associated with ancestry from Iraq, Iran and Afghanistan suggests involvement of genetic determinants, environmental exposures and/or lifestyle factors and mandates further investigation.     

Polycythemia of the preterm and full-term newborn infant: relationship between hematocrit and gestational age, total blood solutes, reticulocyte count, and blood pH.

The umbilical venous hematocrit at birth (Hct 1) and the peripheral venous hematocrit at 2 h of life (Hct 2) were determined in 78 healthy full-term and 14 healthy preterm newborn infants. Hct 1 was 51.6 +/- 4.1% in full-term infants and 50.8 +/- 4% in preterm infants. Hct 2 was 60.9 +/- 2 and 58.6 +/- 6.1% in full-term and preterm infants, respectively. Significant differences between Hct 1 and Hct 2 were found in both groups of infants (p less than 0.01). The blood viscosity increased significantly in both groups from birth to 2 h of life. Neonatal polycythemia (Hct higher than 70% at 2 h of life) was detected in only 3 full-term infants (3.8%). They received partial exchange transfusion. There was a positive linear correlation of Hct 1 with Hct 2 in full-term newborns (r = 0.71, p less than 0.001) and preterm infants (r = 0.57, p less than 0.02). No infants with Hct 1 equal to or below 50% had Hct 2 higher than 65%. None with Hct 1 between 51 and 54% had Hct 2 higher than 70%. Neither Hct 1 nor Hct 2 correlated with birth weight, gestational age, total blood solutes, or reticulocyte counts at birth in either group. An inverse linear correlation was found between blood pH at birth and Hct 2 in preterm newborn infants (r = 0.66, p less than 0.02).     

Clotrimazole decreases glycolysis and the viability of lung carcinoma and colon adenocarcinoma cells

Glycolysis is known to be the primary energy source in most cancer cells. We investigated here the effect of clotrimazole (1-(alpha-2-chlorotrityl)imidazole), the antifungal azole derivative, which was recently recognized as calmodulin antagonist, on the levels of glucose 1,6-bisphosphate and fructose 1,6-bisphosphate, the two stimulatory signal molecules of glycolysis, and on ATP content and cell viability in LL/2 Lewis lung carcinoma cells and CT-26 colon adenocarcinoma cells. We found that clotrimazole induced a significant, dose- and time-dependent reduction in the levels of glucose 1,6-bisphosphate, fructose 1,6-bisphosphate, ATP, and cell viability. These findings suggest that clotrimazole causes a reduction in glycolysis and ATP levels, which eventually leads to cell destruction after 3 h of treatment. Since cell proliferation was also reported to be inhibited by calmodulin antagonists, this substance is most promising agent in treatment of cancer by inhibiting both cell proliferation and the glycolytic supply of ATP required for cancer cell growth.     

Incipient CADASIL

BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is caused by mutations in the NOTCH3 gene. Knowledge of disease expression in young adult NOTCH3 mutation carriers (MCs) is limited. OBJECTIVE: To characterize clinical, neuropsychological, and radiological status in NOTCH3 MCs younger than 35 years. DESIGN: Clinical characterization and blinded survey comparing MCs with non-MCs. SETTING: Referral center. PARTICIPANTS: Individuals younger than 35 years who were at a 50% risk of a NOTCH3 mutation, from our CADASIL database. Thirteen individuals, from 8 families, met the criteria. METHODS: Comprehensive clinical, genetic, neuropsychological, and radiological investigations. Magnetic resonance images were scored according to a standardized white matter hyperintensities rating scale. RESULTS: Six individuals, from 5 families, were MCs. Clinical symptoms consisted of migraine (with aura), stroke, and stroke-like episodes. We did not find evidence for psychiatric disturbances, functional disability, or cognitive dysfunction, compared with non-MCs. Radiologically, a characteristic magnetic resonance imaging lesion pattern emerged for all MCs. This comprised white matter hyperintensities in the anterior temporal lobes, the frontal lobes, and the periventricular frontal caps. CONCLUSIONS: Migraine (with aura) and stroke can present in NOTCH3 MCs younger than 35 years; however, more importantly, physical function and cognition are intact. Possible subtle cognitive dysfunction needs to be assessed in a larger study. White matter hyperintensities on magnetic resonance imaging are characteristic, and are consistently visualized from the age of 21 years and onward. Awareness of the clinical and radiological features of CADASIL in those younger than 35 years should increase early diagnosis and allow for customized counseling of young adults from families with CADASIL.     

Broad expression of Toll-like receptors in the human central nervous system

The family of Toll-like receptors (TLRs) plays a key role in controlling innate immune responses to a wide variety of pathogen-associated molecules. In this study we investigated expression of TLRs in vitro by purified human microglia, astrocytes, and oligodendrocytes, and in vivo by immunohistochemical examination of brain and spinal cord sections. Cultured primary microglia were found to express mRNA encoding a wide range of different TLR family members while astrocytes and oligodendrocytes primarily express TLR2 and TLR3. Comparisons between microglia derived from a series of control subjects and neurodegenerative cases indicate distinct differences in levels of mRNA encoding the different TLRs indifferent microglia samples. Interestingly, expression of TLR proteins in cultured microglia as revealed by immunocytochemistry was restricted to intracellular vesicles, whereas in astrocytes they were exclusively localized on the cell surface. Finally, in vivo expression of TLR3 and TLR4 was examined by immunohistochemical analysis of brain and spinal cord sections from both control and multiple sclerosis brains, revealing enhanced expression of either TLR in inflamed CNS tissues. Together, our data reveal broad and regulated expression of TLRs both in vitro and in vivo by human glia cells.     

Treatment of severe, drug resistant obsessive compulsive disorder with the 5HT1D agonist sumatriptan

The serotonergic system has been implicated in both the aetiology and pharmacological treatment of obsessive compulsive disorder. In pharmacological challenge tests, mCPP, a 5-HT agonist, with an affinity for 5HT_2C as well as 5HT_1A and 5HT_1D, receptors, was associated with a transient exacerbation of obsessive compulsive symptoms. Chronic administration of mCPP was found to bring about some relief of these symptoms. Sumatriptan is an antimigraine agent, which interacts most potently with 5HT_1D receptors. In the cases to be presented, we report the effects of chronic administration of Sumatriptan to three severe, treatment resistant, OCD patients. Following chronic administration of sumatriptan, these patients, who have been resistant to any former pharmacological treatment, responded with an improvement in their depression and a modest reduction in their obsessive compulsive symptoms.