[Cytogenetics of oral solid tumors].

The tumorigenesiss of oral solid tumors is still uncertain. The underlying mechanisms of epithelial or connective tissue proliferation are not yet fully understood. Also, the transformation of a benign tumor into malignant is obscure. Cytogenetics is the study of chromosome number and structure using a light microscope. Human chromosome nomenclature is based on An International System for Human Cytogenetic Nomenclature (ISCN). The normal human somatic cells have 46 chromosomes, including 22 pairs of autosomes and two sex chromosomes, XX in female and XY in male. The chromosome abnormalities can be numerical and structural. Both types can occur concurrently. Numerical abnormalities involve the loss and/or gain of a whole chromosome and can include both autosomes and sex chromosomes. Cells which have lost a chromosome are categorized as a monosomy, while those with an extra chromosome are trisomy. Structural abnormalities include translocations, deletions, inversions and insertions. Cancer, in its various forms is a result of genetic changes. This concept comes from the finding of chromosomal abnormalities. These abnormalities may arise as a consequence of random replication errors; exposure to carcinogens; or damaged DNA repair process. In clinical oncology, the study of chromosome abnormalities in solid tumors provides valuable information for the diagnosis, evaluating treatment response of metastatic cancer, marker for prognosis and targeted therapy. In tumors which histologic features overlap, cytogenetics plays an important role for diagnosis. Cytogenetics has also been used to monitor the surgical margins of the resection in head and neck carcinoma, where the histology was not definitive. The present report will focus on the role of cytogenetics in the diagnosis and prognosis of benign and malignant oral solid tumors.

Dependence of maternal serum [AFP]/[hCG] median ratios on age of gestation: comparison of trisomy 21 to euploid pregnancies.

BACKGROUND: Current risk calculations for trisomy 21, which are based on multiples of median (MoM), do not take into account possible differences between euploid and trisomy 21 pregnancies that may develop with gestational age. In order to optimize the predictive value of screening tests, we calculated the ratio between maternal serum concentration of alpha-fetoprotein (AFP) and that of human chorionic gonadotropin (hCG) in euploid and in trisomy 21 pregnancies. METHODS: The medians of the concentration ratios, [AFP]/[hCG] at 16-21 weeks of gestation, were plotted as a function of gestational age for 307 cases of trisomy 21 and were compared with the medians of 30 549 normal karyotype cases. RESULTS: [AFP]/[hCG] ratio medians were independent of body weight and maternal age. There was a significant difference in the [AFP]/[hCG] ratio when comparing trisomy 21 and euploid pregnancies at each week. This difference became greater with advancing gestational age (P < 0.01). CONCLUSION: There is a significant difference in ratios of [AFP]/[hCG] between euploid and trisomy 21 pregnancies, which may be used to improve detection rates of Down syndrome screening.

Prior joint disease is associated with increased risk of periarticular histiocytic sarcoma in dogs.

Periarticular histiocytic sarcoma (PAHS) is the most common synovial tumour in dogs and is characterized by aggressive local disease with a high rate of distant metastasis. Previously, an association between PAHS and prior joint disease has been demonstrated in the Bernese Mountain Dog breed and suggested in the Rottweiler. We hypothesized that this association would be present in other breeds and investigated this via a retrospective, case-controlled analysis. Cases were dogs diagnosed with PAHS of the stifle or elbow. Controls were age, breed and sex-matched dogs without a diagnosis of histiocytic sarcoma. Diagnosis of prior joint disease was determined based on review of medical records and direct veterinarian and owner communications. Data were evaluated using logistic regression, 2-sampled t tests, and chi-squared analysis. Our study population consisted of 28 cases and 46 controls, including Flat-Coated, Golden and Labrador Retrievers, Rottweilers, English Bulldogs, Shih Tzus, Australian Shepherds, Staffordshire Terriers and mixed breed dogs. Dogs with PAHS were more likely to have prior joint disease in the tumour-affected joint compared with the control population (odds ratio [OR] = 13.42, P < .0001, 95% confidence interval [CI] = 4.33-48.63). A total of 88.2% of dogs with stifle PAHS had prior joint disease in their tumour-affected joint, most commonly cranial cruciate ligament rupture. This study confirms that the previously noted association between prior joint disease and PAHS in Bernese Mountain Dogs also applies to other breeds. Additional studies are needed to further investigate for a causal relationship.

Deletion of 8.5 Mb, including the FMR1 gene, in a male with the fragile X syndrome phenotype and overgrowth.

A four-year-old boy with severe psychomotor retardation, facial appearance consistent with the fragile X syndrome, hypotonia, and overgrowth was found to have a deletion including the fragile X gene (FMR1). The breakpoints of the deletion were established between CDR1 and sWXD2905 (approximately 200 kb apart) at Xq27.1 (centromeric) and between DXS8318 (612-1078L) and DXS7847 (576-291L) (approximately 250 kb apart) at Xq28, about 500 kb telomeric to the FMR1 gene. The total length of the deletion is approximately 8.5 Mb. The propositus's mother, who was found to be a carrier of the deletion, showed very mild mental impairment. Except for mental retardation, which is a common finding in all cases reported with similar deletions of chromosome Xq, this patient had generalized overgrowth, exceeding the 97th centile for height and weight. Obesity and increased growth parameters have been reported in other patients with deletions either overlapping or within a distance of 0.5 Mb from the deletion in the present patient. Thus, it is suggested that a deletion of the 8-Mb fragment centromeric to the FMR1 gene might have an effect on growth.

Tumor necrosis factor alpha and prostaglandin E2 production by human monocyte-derived macrophages infected with spotted fever group rickettsiae.

Infection of macrophages by intracellular parasites might modulate production of tumor necrosis factor (TNF) and prostaglandin E2 (PGE2), which, in turn, might have a profound effect on the outcome of the infection in vivo. In this study we examined in an in vitro system, the rickettsial yield in human monocyte-derived macrophages (MdM) and the PGE2 and TNF production by MdM infected with Rickettsia conorii RC, Casablanca strain) or Israeli spotted fever (ISF, G-212 strain). TNF and PGE2 were determined in the media of MdM infected with RC or ISF. TNF reached maximum levels 24 h post-infection and then declined, while PGE2 levels increased continuously during the infection up to 96 h post-infection. Addition of dexamethasone inhibited both TNF and PGE2 production and enhanced rickettsial yield in MdM. Inhibition of PGE2 production by indomethacin resulted in increased production of TNF from rickettsial-infected MdM, while addition of PGE2 caused partial inhibition of TNF production from infected MdM.

Spotted fever rickettsiae in ticks from the northern Sinai Governate, Egypt.

A field study was initiated in 1988 to investigate whether spotted fever group rickettsiae occur in geographic areas in Egypt that are adjacent to an area in the southern Israeli Negev that has a defined focus of spotted fever disease. Ticks were collected from dogs, sheep, and camels at four study sites in the northern Sinai. Tick hemolymph was processed for rickettsial detection by staining with fluorescein isothiocyanate-conjugated antibody to Rickettsia rickettsii. Of the 442 hemolymphs examined, 15 contained immunofluorescent rickettsiae. Eight hemolymph test-positive (HT+) ticks were Rhipicephalus sanguineus removed from dogs; the other HT+ ticks comprised three Hyalomma species, H. anatolicum, H. impeltatum, and H. dromedarii. Both HT+ and HT- ticks were tested for rickettsial DNA using the polymerase chain reaction (PCR). Eight of 10 HT+ field-collected ticks were PCR positive (PCR+). All laboratory colony R. rickettsii-infected ticks were PCR+. No HT- ticks from field or laboratory isolates were PCR+.

Comparative antigenic analysis of spotted fever group rickettsiae from Israel and other closely related organisms.

Spotted fever rickettsiosis in Israel has been considered as possibly somewhat more severe than boutonneuse fever, from which it also differs in having a very low proportion of cases with a tick-inoculation site eschar. This investigation was undertaken to determine whether the Israeli spotted fever group (SFG) rickettsiae differed sufficiently from Rickettsia conorii to be considered as a distinct species. Strains of Rickettsia conorii from Morocco and South Africa, four SGF rickettsial isolates from Israel, one from Russia, and one from Zimbabwe were compared by microimmunofluorescence serotyping, Western immunoblotting, monoclonal antibody reactivity, and polymerase chain reaction amplification of the repeat domain of the rickettsial outer membrane protein A (rOmpA). All are strains and isolates of R. conorii, yet there is considerable molecular and antigenic diversity of both rOmpA and rickettsial outer membrane protein B (rOmpB) among them. The rOmpA gene of the Israeli isolates and the Astrakhan strain from Russia is estimated to encode 15 rOmpA repeat units as compared with 10 for the South African strain and six for the strains from Morocco and Zimbabwe. The Israeli SFG rickettsial strains appear to be R. conorii, a species with substantial antigenic and genetic diversity. The Israeli strains appear to fall within the limit previously described for the genetic and antigenic diversity of R. conorii.

Intracellular persistence of chlamydial major outer-membrane protein, lipopolysaccharide and ribosomal RNA after non-productive infection of human monocytes with Chlamydia trachomatis serovar K.

The replication of Chlamydia trachomatis serovar K was studied in human peripheral blood monocytes (PBMo). The intracellular fate of the bacteria was examined by determining the presence of chlamydial major outer-membrane protein (MOMP), lipopolysaccharide (LPS) and ribosomal RNA (rRNA). In-vitro infection of PBMo with C. trachomatis serovar K was not productive. However, chlamydial MOMP antigen, demonstrated by immunofluorescence, was present in PBMo for up to 14 days. Infected monocytes also contained chlamydial rRNA, measured by in-vitro hybridisation, and LPS, measured by enzyme immunoassay, for up to 14 days. These data are compatible with the hypothesis that the infection of PBMo with C. trachomatis may play a role in the systemic distribution of chlamydial antigens, leading to systemic manifestations of urogenital chlamydial infection.

Acute blast crisis with EBV-infected blasts, in a patient with chronic myeloid leukemia, and vasculitis.

Unless they undergo transplantation, all patients with chronic myeloid leukemia (CML) will eventually develop a late phase of acute blast crisis (ABC). Although additional chromosomal abnormalities to the Philadelphia (Ph) chromosome may herald ABC in many CML cases, the mechanisms leading to this fatal event are obscure. Viral etiology, including the Epstein-Barr virus (EBV) has never been implicated in the pathogenesis of ABC in CML. Iloprost is an analogue of epoprostenol (prostacyclin; PGI2) commonly used for the treatment of peripheral vascular diseases and acts via inhibition of platelet activation, and by vasodilation. A case of ABC with blasts of undetermined lineage showing EBV infection in a male patient with Ph positive CML is described here. This unusual event developed during a course of treatment with the prostacyclin analogue, iloprost administered for vasculopathic leg ulcers. The proliferating blasts stained positively by immunohistochemistry only for the leukocyte common antigen (LCA/CD-45), and the EBV-latent membrane protein 1 (LMP-1). The only chromosomal abnormality detected by cytogenetic analysis was the conventional Ph-chromosome. It is suggested that ABC in this case of CML, was associated with EBV-activated blasts of undetermined lineage.

Papilledema in endemic typhus.

A 21-year-old women developed severe bilateral papilledema during an acute febrile disease. Her optic disk margins were blurred and the disks were elevated up to 5 diopters. Splinter hemorrhages, cotton-wool exudates, cytoid bodies, and sheathing of veins were also present. The pyrexia was caused by murine typhus diagnosed by serologic tests. These tests revealed that Proteus OX-19 agglutination titer rose to 1:12800, and a positive complement fixation test titer was 1:640 with Rickettsia mooseri antigens. Neurological examination results, skull roentgenograms, brain scan, electroencephalogram, and the cerebrospinal fluid were all within normal range, thereby excluding intracranial hypertension. After the patient's recovery from the rickettsial disease, the papilledema abated gradually until her fundi reverted to normal.

Q-fever pneumonia in the Negev region of Israel: a review of 20 patients hospitalised over a period of one year.

BACKGROUND: Three-hundred and forty-six patients with community acquired pneumonia were included in a prospective study of patients hospitalised over a 12-month period in the Soroka Medical Center in Beer-Sheva, Israel. Q-fever pneumonia (QFP) was diagnosed in 20 patients (5.8%). A detailed epidemiological and clinical description of this disease, is presented. METHODS: QFP was diagnosed by conventional criteria using a commercial immunofluorescent assay. RESULTS: The age of patients was 41 +/- 14 years (mean +/- S.D., range 20-69). Twelve of the patients were males. No concomitant or chronic disease was present in 16 patients. Chest radiograms revealed alveolar or air space pneumonia in 10 patients, bronchopneumonia in nine and interstitial pneumonia in one patient. The mean febrile period was 10.5 +/- 5.3 days. There was serological evidence of co-infection with Mycoplasma pneumonia in six patients, and with Legionella pneumophila in one patient. Patients treated with beta-lactam antibiotics recovered as quickly as those treated with tetracyclines or erythromycin. CONCLUSIONS: The Negev region of Israel is an endemic area for Q-fever. The diagnosis of QFP can be made only on the basis of a specific serological test. Clinical, radiologic or laboratory findings are not diagnostically definitive. The importance of specific therapy is unclear.

Ecological studies on the brown dog tick Rhipicephalus sanguineus (Acari: Ixodidae) in southern Israel and its relationship to spotted fever group rickettsiae.

An outbreak of spotted fever group rickettsiae (SFGR) was investigated by studying free-living and parasitic stages of ticks in two settlements of equal size and population located 20 km apart in the Negev Desert. Although high morbidity from SFGR was found in one of the settlements (Kibbutz Ze'elim), no clinical cases were observed in the second (Kibbutz Re'im). Using flagging and CO2-trapping, approximately 9 times more ticks were collected in Ze'elim than in Re'im. Rhipicephalus sanguineus (Latreille) was the dominant species in Ze'elim, whereas in Re'im R. turanicus Pomerantzev was the most abundant species. Several physical factors that may account for these differences were investigated. Significantly higher maximum soil temperature as well as ambient temperature above the soil were found in Ze'elim. Differences in soil composition in the two sites were also observed. Tick numbers were especially high during April through October in Ze'elim, whereas in Re'im, ticks were found mainly from April to July. A significant positive correlation was found between temperature and tick population size in Ze'elim. Dogs, sheep, goats, Mus musculus, and Meriones crassus, were more heavily infested with ticks in Ze'elim than in Re'im. The percentage of mice and dogs seropositive to SFGR was the same in both sites. In Ze'elim, 7.1% of dog owners acquired Mediterranean spotted fever during the period 1984-1989 compared with only 1.4% of people without dogs.

Prevalence of vectors of the spotted fever group Rickettsiae and murine typhus in a Bedouin town in Israel.

A survey of the vectors of spotted fever group Rickettsiae and of murine typhus was carried out in Rahat, a Bedouin town in the Negev Desert, where the diseases are endemic. Houses with known cases of spotted fever group Rickettsiae or murine typhus were compared with those without reported clinical cases. A neighboring Jewish community, Lehavim, where no cases of spotted fever group Rickettsiae and murine typhus were reported in recent years, was used as a control. In the houses of patients with spotted fever group Rickettsiae in Rahat, an average of 7.4 times more ticks were found than in control houses. Out of 190 ticks isolated from sheep and goats or caught by flagging in Rahat, 90% were Rhipicephalus sanguineus (Latreille), 7.9% Rhipicephalus turanicus Pomerantzev, and 2.1% were Hyalomma sp. In the houses of patients with murine typhus, three times more rats were caught and, on the average, each rat was infested with 2.2 times more fleas than rats in the control houses. Out of 323 fleas collected from 35 Norwegian rats (Rattus norvegicus Berkenhout), 191 were Xenopsylla cheopis Rothschild and 132 Echidnophaga murina Tiraboschi. Thus, there was a six to seven times higher probability of encountering a tick or flea vector where infections had occurred than in control houses in Rahat. The percentage of rats seropositive to Rickettsia typhi was similar in study and control households (78.3 and 76.2, respectively). In the control settlement, Lehavim, only three Mus musculus L. were caught, which were not infested with ectoparasites and their sera were negative for murine typhus. Out of 10 dogs examined in this settlement, 15 R. sanguineus and eight specimens of the cat flea (Ctenocephalides felis felis Bouché) were isolated. No rats were caught in this settlement. These data indicate that there is a correlation among the density of domestic animals, their ectoparasites, and the incidence of spotted fever group Rickettsiae and murine typhus in Rahat.

Comparison of nucleoside transport binding sites in rabbit iris-ciliary body and cultured rabbit nonpigmented ciliary epithelial cells.

The iris-ciliary body (ICB) is a site of action for topically applied antiglaucoma drugs. Moreover, adenosine has been implicated as a modulator of aqueous humor dynamics. The present study compares the binding of the nucleoside transporter probe, [3H]nitrobenzylthioinosine ([3H]NBMPR), to homogenates prepared from rabbit ICB and a cultured rabbit nonpigmented ciliary epithelial cell line (NPE) to determine whether NPE can be used as an experimental model to study the nucleoside transporter. Linear transformation of the saturation binding data revealed that [3H]NBMPR binds to a homogeneous population of binding sites with similar binding affinities (Kd = 0.3 +/- 0.1 and 0.6 +/- 0.1 nM in NPE and ICB, respectively). However, the maximal binding capacity in NPE (Bmax = 288 +/- 54 fmol/mg protein) was significantly higher than that in ICB (Bmax = 154 +/- 17 fmol/mg protein). Selected inhibitors of the nucleoside transport system and structural analogs of adenosine inhibited the binding in both homogenate preparations with a similar rank order of potency: NBMPR > DPY > CV-1808 > CHA > R-PIA > S-PIA > 2-CADO > NECA. The results suggest that NPE is a useful model which could be used for characterizing the nucleoside transporter in ICB and for the screening of nucleoside transport inhibitors as potential antiglaucoma drugs.

Acquired chromosome instability in the elderly--the effect of diepoxybutane.

Aging and Alzheimer's disease (AD) have been the subject of many studies. It has been suggested that chromosomal alterations may be involved in the etiology and/or pathogenesis of ageing and AD. The purpose of the present study was to examine the effect of diepoxybutane (DEB) on lymphocyte chromosomal instability in the elderly. We examined lymphocytes cytogenetically with, as well as, without DEB treatment, in a group of 12 elderly (range of age 72-96 years), nine of them suffering from AD type. Without DEB treatment six of the donors expressed chromosomal instability in at least 6% of the analyzed cells. After treatment with DEB, lymphocytes showed an increase in the chromosomal instability in up to 20% of the analyzed in eight donors. The sex chromosomes were the main chromosomes involved in the acquired chromosomal abnormalities. It is not clear from this study whether this chromosomal instability is related to the AD. The significance of the involvement of sex chromosomes either in ageing or in AD, as well as, the question whether the chromosomal instability is the cause of or part of ageing processes, has to be addressed.

The effect of monocyte-derived macrophages on the growth of Rickettsia conorii in permissive cells.

We examined whether monocyte-derived macrophages (MdM) incubated with rickettsia-infected HEp-2 or BGM cells a) affect R. conorii (Boutonneuse fever) growth, and b) secrete TNF and IL-1 alpha. BGM and HEp-2 cells were infected with R. conorii at multiplicities of infection (MOI) of 1-0.01. After 2 hr of adsorption, the cells were washed and MdM were added at an effector to target ratio of between 3 and 5. At 2, 24, 48, and 96 hr post-infection (p.i.) cells were scraped off; cell-free medium was collected and TNF and IL-1 levels were determined by ELISA and RIA, respectively. MdM caused a 50-70% reduction in the yield of R. conorii in HEp-2 cells as compared to the control (infected HEp-2 cells incubated without MdM). This reduction was more pronounced at MOI 0.1 and 0.01, than at MOI 1. In contrast, no reduction in the rickettsial yield was observed in the BGM cells incubated with MdM. TNF and IL-1 alpha levels in the cell-free medium from infected HEp-2 cells incubated with MdM were higher (2-5 fold) than those from infected BGM cells incubated with MdM. These data suggest the possibility that, and the mechanisms whereby, MdM may modulate rickettsia replication in vivo.

Serum antibodies in rickettsia patients as determined by immunoblotting technique.

The Western-blot technique (WB) was used to determine which polypeptides of Israeli spotted fever (ISF) isolates and other spotted fever group rickettssia (SFGR) reference isolates (G212, S484, A828) and two reference strains. R. Rickettsii (Sheila Smith strain) and R. conorii (Boutonneuse fever), were used as antigen sources for the WB. Immunoperoxidase assay (IPA) seropositive (titer greater than 80) and seronegative (titer less than) sera were examined with the separated polypeptides of the above strains. WB analysis of the rickettsial polypeptide-serum reactions showed that R. conorii and the three isolates of ISF reacted identically with the sera, except that in the three ISF strains a 175 kD protein was present. It was also observed that all of the IPA seropositive sera examined reacted with the following polypeptides: 18kD, 20kD, 22kD (28kD to 37 kD LPS group), while each seropositive and seronegative serum reacted differently with polypeptides 23kD, 42kD, 45kD, 46kD, 52kD, 55kD, 70kD, 82kD, 105kD, 125kD, 155kD and 175kD. Using this technique, no heat labile polypeptides (preelectrophoretic treatment: 100 degrees C for 2 min vs 37 degrees C for 20 min) were observed in SFGR strains used in this study. Our results indicate that the immunoblot technique shows no difference between R. conorii and ISF antigens except the existence of 175kD protein antigen in the latter.

Comparison of structural polypeptides, detected by immunoblotting technique, in the sera of spotted fever group rickettsia positive cases--symptomatic versus asymptomatic.

In an attempt to characterize the nature of symptomatic versus asymptomatic spotted fever group rickettsia (SFGR) infection, the immune response to R. conorii (boutonneuse fever) structural polypeptides was studied by Western-blot immunoassay. Sera from immunoperoxidase assay (IPA), SFGR seropositive (titre greater than or equal to 80) individuals, symptomatic and asymptomatic and from SFGR seronegative (IPA titre less than 80) individuals living in a kibbutz community in the desert region of Southern Israel were examined by immunoblot. This community suffered from a very high morbidity rate due to SFGR (21-fold higher than the national reported average). The entire community (n-326) has been followed-up since 1985, with serial serum samples being examined for specific IgG antibodies by IPA. The intensity of the immunoblot reaction correlated with specific IgG antibody titres as determined by IPA. This correlation was also observed between the decrease in the IgG titre and the strength of the antibody-antigen reaction by immunoblot over time for a given individual. IPA seropositive sera from asymptomatic as well as symptomatic spotted fever cases reacted to 8 individual polypeptides. In both cases antibodies to 22 kD, 24 kD, 26 kD, 28 kD, 30 kD, 32 kD, 34 kD, and 37 kD were found. In the IPA seronegative sera, antibodies to polypeptides in the range of 24 kD to 32 kD were not detected. The lack of detectable differences by immunoblotting between SFGR symptomatic vs, asymptomatic cases might be explained by other aspects of the immune response of each infected individual, and/or it is possible that virulent and non-virulent antigenically closely related SFGR strains infected symptomatic vs. asymptomatic individuals.