Search

Lynch syndrome is an inherited cancer predisposition syndrome caused by germline defects in any of the mismatch repair (MMR) genes. Diagnosis of carriers makes precision prevention, early detection, and tailored treatment possible. Herein we report a novel founder deletion of 18,758 bp, mediated by Alu repeats on both sides, detected in Ethiopian Jews. The deletion, which encompasses exon 9-10 of the MSH2 coding sequence, is associated mainly with early-onset MSH2/MSH6-deficient colorectal cancer (CRC) and liposarcoma. Testing of 35 members of 5 seemingly unrelated families of Ethiopian origin yielded 10/21 (48%) carriers, of whom 9 had CRC. Age at first tumor diagnosis ranged from 16 to 89 years. Carriers from the oldest generations were diagnosed after age 45 years (mean 57), and carriers from the younger generation were diagnosed before age 45 years (mean 30). Awareness of this founder deletion is important to improve patient diagnosis, institute surveillance from an early age, and refer patients for genetic counseling addressing the risk of bi-allelic constitutional MMR deficiency syndrome.

Little is known about the effects of immunosuppression on patients with hereditary nonpolyposis colorectal cancer (HNPCC). We describe a kidney transplant recipient with unrecognized Muir-Torre syndrome in whom the administration of a tacrolimus-based regimen led to the eruption of multiple sebaceous tumors. The patient was later found to harbor an MSH2 mutation. Switching to a sirolimus-based regimen resulted in arrest of the disease. When the patient was switched back to tacrolimus, new facial lesions rapidly appeared. Switching again to sirolimus resulted again in halting the appearance of new lesions. This finding is in line with the known antiangiogenic activity of sirolimus and reports on the regression of cutaneous Kaposi's sarcoma in kidney transplant recipients switched from another immunosuppressive regimen to sirolimus. Further studies on the potential use of sirolimus for the treatment of de novo tumors in immunosuppressed kidney transplant recipients with HNPCC are warranted.

We attempted to demonstrate a relation between a loss of replication control, centromere dysfunction, and predisposition to non-disjunction. Couples with a Down syndrome offspring were the high-risk probands. One-color FISH (fluorescent in-situ hybridization) was applied to interphase nuclei (lymphocytes). Replication pattern of two pairs of alleles, RB-1 and 21q22, were studied, and the rate of aneuploidy was estimated using two alpha-satellite probes of chromosomes 8 and 18. Our results suggest the existence of an association between replication timing and the rate of non-disjunction. A higher rate of allele asynchrony and aneuploidy was found in older women and in mothers of a Down syndrome offspring. These findings may reflect a predisposition for meiotic non-disjunction in these women.

Aqueous extracts of 66 desert plants of the Negev and Beer Sheva Bedouin market plant products were tested for antitumor, antimalarial (protozoa) and growth inhibition of wheat-rootlet activities. Pteranthus dichotomus, Gypsophila arabica, Achillea fragrantissima, Urginea maritima, and Solanum elaeagnifolium exhibited strong cytotoxicity (above 97%) against cultured melanoma cell lines. Mesembryanthemum nodiflorum, Gypsophila arabica, Hammada scoparia, Trigonella foenum-graecum and Peganum harmala had more than 80% inhibition both in rootlet and melanoma assays. Hammada scoparia, Pulicaria crispa, Centaurea eryngioides, Echinops polyceras, Ephedra aphylla, Teucrium polium, Phlomis brachyodon, Urginea maritima, Ochradenus baccatus, Verbascum fruiticulosum, Corchorus olitorius, and Peganum harmala demonstrated strong growth inhibition (above 96%) of the malaria parasite Plasmodium falciparum. The plants that were positive for antimelanoma and antimalarial activities have been under further investigation for...

The clinical significance of mosaicism trisomy 20 detected prenatally following amniocentesis remains uncertain, due to the rarity of liveborn cases with inconsistent clinical findings, the short postnatal follow-up, and failure in evaluating other fetal tissues for the presence of the trisomy. We report on a 15 month-old 46,XX chromosome constitution in white blood cells, while skin fibroblasts demonstrated trisomy 20 mosaicism (54%) by fluorescence in situ hybridization (FISH) analysis. Clinical examination of the baby showed only minor phenotypic signs (bilateral epicanthal folds, delayed closure of fontanel with no other gross anomalies), but demonstrated a considerable developmental delay in gross and fine motor skills along with hypotonicity. This is the second oldest described liveborn with trisomy 20 mosaicism confirmed in skin fibroblasts. This cytogenetic aberration along with her developmental delay suggests that the two findings are related and that aberration affects various fetal tissues and is not confined to extra-embryonic tissue as suggested previously. Yet, an undiagnosed condition may be the cause of the child's developmental delay. Based on this case and following a review of the literature we suggest that when mosaic trisomy 20 is identified in amniocytes, further evaluation is required. Cord blood should be analyzed preferably by FISH. During counseling the parents should be advised of an additional risk, such as developmental delay, even when fetal cord karyotype and detailed ultrasonic scan are normal.

This study was undertaken in an attempt to determine the significance of elevated maternal serum human chorionic gonadotropin (MShCG), in the presence of an otherwise normal screen with respect to fetal malformations, chromosomal aberrations, and pregnancy outcome. Targeted ultrasound findings and perinatal outcome of 298 women in whom serum hCG was > or = 2.5 MOM and who were screen-negative for Down syndrome (the study group) were compared with a control group of 229 women in whom serum hCG as well as the other parameters were within the normal range. Genetic amniocentesis was performed in 125 women from the study group. Ultrasonically detected malformations were significantly more frequent among the study group (12 vs. 1, P = 0.01). Pregnancy complications were similar in the two groups, with the exception of pre-eclampsia-toxaemia, which was significantly more frequent in the study group (5 vs. 0, P = 0.02). There was one case of an abnormal karyotype (47,XXY). Although genetic amniocentesis does not appear warranted, isolated elevated MShCG levels during the second trimester screening was associated with an increased risk of fetal anomalies detected by ultrasound and of toxaemia of pregnancy.

Cytogenetic and fluorescent in situ hybridization (FISH) studies were performed on several formalin-fixed tissues obtained from four fetuses diagnosed at amniocentesis as 45,XO-Turner syndrome. Three of the four were phenotypically normal and one had malformations. The three phenotypically normal cases were found to have an additional normal cell line, which may explain their ability to survive, at least to the time of pregnancy termination well into the second trimester. The abnormal 45,XO fetus was not found to be mosaic in all of the tissues examined. In 45,XO cases in which no malformation is detected, the possibility of mosaicism should be raised and thus the counselling should be modified accordingly.

Incorporation of maternal serum unconjugated estriol into the calculation of risk may increase the yield of serum screening performed during pregnancy for detection of fetal chromosomal and structural anomalies. The differential diagnosis of very low and undetectable levels of unconjugated estriol in maternal serum is discussed, with special emphasis on the prenatal diagnosis of X-linked ichthyosis. The prenatal detection of these findings dictates skilled genetic counseling, targeted sonographic evaluation and examination of fetal karyotype and fetal cDNA for Xp 22.32 with amniotic fluid levels of cortisol, STS, and ASC.

Five cases of supernumerary marker chromosomes were identified in prenatal diagnosis as derived from chromosomes 18, X, and Y. One unexpected finding was in a case where the PCR was positive for the SRY gene while fluorescence in situ hybridization was positive for two X centromeres. In another case with an X derived supernumerary marker the newborn was phenotypically normal. Two women with fetal mar(18) and mar(Xp) decided to terminate the pregnancy. The fifth pregnancy had a karyotype of 46,XX,-15,+der(15)t(Y:15)(q11,23;p13). A phenotypically normal girl was born at term.

The aim of this pilot study was to assess the clinical and immunological effects of human allogeneic liposomal melanoma vaccine alone or combined with Interleukin-2 (IL-2) in patients with metastatic melanoma. Four concurrent treatment arms were included: vaccine alone (A); vaccine combined with systemic IL-2 (B); vaccine combined with low-dose liposomal regional IL-2 (C); and low-dose regional IL-2 as in group C but without vaccine (D). Vaccine was prepared from semisynthetic phospholipids (dimyristol phosphatidylcholine and dimyristol phosphatidylglycerol) and membranes of six human melanoma cell lines. The latter were chosen as expressing MHC class I and II antigens and a "mosaic" of melanoma-associated antigens (MAAs) as detected by MoAbs R24, p97, CF21 and TA99. Nine of the 24 patients had objective clinical responses: of the ten patients treated with liposomal vaccine and low dose regional IL-2 (arm C), three had complete responses (CR) and three had partial responses (PR); of the five patients treated with liposomal, low-dose regional liposomal IL-2 only (arm D), three had PRs. No clinical responses were seen in patients treated by vaccine alone (A) nor in patients treated by vaccine and systemic IL-2 (B). Patients' in vivo and in vitro cellular immune responses were closely monitored. Conversion to positive cutaneous delayed type hypersensitivity (DTH) to membrane vaccine (without liposomes) was induced only in the six clinical responders of arm C. Positive DTH correlated with augmented in vitro proliferative lymphocyte responses stimulated by melanoma cell lines and membrane preparation and with the augmented cytolytic activity against melanoma cell lines.

Objective A study was conducted to evaluate the sensitivity of combining a second trimester triple test and targeted ultrasound in order to detect Down syndrome in women undergoing amniocentesis over 35 years of age. Methods Women over 35 years of age underwent a triple test and an ultrasound examination for chromosomal markers immediately prior to genetic amniocentesis. Results One thousand and six women were examined. Four hundred and thirty seven were triple test-positive and in 195 cases ultrasonographic abnormalities were observed. Thirteen had Down syndrome and eight had other chromosomal abnormalities. All women with Down syndrome babies were triple test-positive and seven also had ultrasonographic markers. Three of eight women who had babies with chromosomal aberrations other then Down syndrome were also triple test-positive. Conclusions The use of the triple test as a screening tool in our population would reduce the number of amniocenteses by 60%, while no cases of Down syndrome would be missed. Ultrasonographic markers have added little to this population. Three non-Down syndrome chromosomal abnormalities and two Down syndrome mosaic cases would be missed by this approach. Copyright © 2002 John Wiley & Sons, Ltd.

We attempted to demonstrate a relation between a loss of replication control, centromere dysfunction, and predisposition to non-disjunction. Couples with a Down syndrome offspring were the high-risk probands. One-color FISH (fluorescent in-situ hybridization) was applied to interphase nuclei (lymphocytes). Replication pattern of two pairs of alleles, RB-1 and 21q22, were studied, and the rate of aneuploidy was estimated using two alpha-satellite probes of chromosomes 8 and 18. Our results suggest the existence of an association between replication timing and the rate of non-disjunction. A higher rate of allele asynchrony and aneuploidy was found in older women and in mothers of a Down syndrome offspring. These findings may reflect a predisposition for meiotic non-disjunction in these women.

We evaluated the feasibility of retrospective genetic testing for numerical chromosomal aberrations by applying the FISH technique to formalin-fixed fetal tissue. Fetal tissue from 10 old cases with known aneuploidy and from 13 cases with known fetal malformations, were tested with specific DNA probes for pericentromeric repeat regions of chromosomes 13/21, 18, X and Y. FISH diagnosis concurred with karyotype in all nine cases with sufficient cells. Numerical aberration was diagnosed in six out of 13 cases with fetal malformations.

Muramyl tripeptide phosphatidylethanolamine (MTP-PE; CGP 19835A from Ciba Geigy) is a synthetic muramyl tripeptide structurally related to bacterial cell wall constituents. MTP-PE activates monocytes in vitro to a tumoricidal state and has in vivo antitumor effects in animal models. We studied the toxicity and immunomodulatory effects of once weekly i.v. administration of liposomal-encapsulated MTP-PE for 8 weeks in 27 patients with advanced malignancies. Doses ranged from 0.1 to 2.7 mg/m2. No major tumor responses were seen; 11 patients had stable disease after 8 weeks of therapy and 3 continued on maintenance therapy because of minor tumor regressions and/or clinical improvement. MTP-PE at these doses was well tolerated. Shaking chills and fevers were the most common toxicities and occurred at all dose levels. There was no treatment-induced loss of performance status. Immunomodulatory studies revealed evidence of a biological effect on monocytes. C-reactive protein levels rose in the majority of patients with end-of-treatment values 2 to 10 times higher than baseline. Serum neopterin levels were consistently increased 24 h after MTP-PE administration and significant decreases in expression of two different types of Fc receptors on peripheral blood monocytes were noted 6 h after treatment. Although no major tumor responses were seen in this group of patients with advanced malignancies, MTP-PE was well tolerated and exerted biological effects on monocytes. Serum neopterin levels may be a useful marker for the biological effects of MTP-PE.

Standardization of the measurement of amyloid degrading activity (ADA) by diffusion of serum in amyloid-impregnated agar plates may either indicate or exclude with reasonable certainty the presence of systemic AA amyloidosis. In certain cases, it may obviate the need for a diagnostic biopsy. The sera of 38 patients with systemic amyloidosis were tested and compared with sera of 38 controls matched for age, serum creatinine and albumin blood levels, and with sera of 48 additional controls with the same basic diseases as the amyloidotic patients but without amyloidosis. The difference between ADA of amyloidotic and control patients was significant, with no overlap in the range of activity between the two groups. A positive correlation was found between ADA and serum albumin concentration in the nonamyloidotic matched controls but not in patients with amyloidosis. Our data do not support the view that the decline in ADA of sera of amyloidotic patients is due to hypoalbuminemia.

Experiments with two models of intestinal ischemia were performed in order to examine the protective effect of dimethyl sulfoxide (DMSO). Segmental ischemia of the small intestine for 150 minutes caused necrosis of the affected bowel in 90% of the animals. Intravenous administration of DMSO or impregnation of the peritoneum with this substance prevented the development of gangrene in 28 of 29 rats. 30 or 60 minutes of complete ischemia of the small intestine, produced by clamping of the superior mesenteric artery, resulted in partial or complete necrosis of bowel segments with a high incidence of perforation and peritonitis and a high mortality rate within the first 24 hours. Intravenous DMSO, given upon declamping of the artery, effectively protected the bowel from the ischemic damage. There were no deaths among DMSO-treated animals and at 24 h there was no evidence of ischemic damage to the intestine. Though the exact mechanism of action of DMSO is unknown, the results of these and other experiments may warrant clinical trials especially in cases of mesenteric thrombosis.

We studied the influence of unactivated mouse peritoneal macrophages on the proliferative capacity of a spontaneously transformed MRL-lpr/lpr T cell clone. Macrophages, 25%, induced a reduction in proliferative rate from 20% to 95% measured by [3H]thymidine incorporation and microscopic cytometry. MHC-compatible (H-2k) macrophages caused growth inhibition reciprocal to the amount of Ia expression on the macrophage. Thus, with increasing preculture of the macrophages there was both decreasing Ia and increasing suppression. H-2-incompatible macrophages had maximal inhibitory capacity without preincubation. Macrophages derived from the peritoneum of MRL-lpr/lpr mice were less suppressive than macrophages from other H-2k mice. In contrast to the case of activated macrophages in other studies, in the present system there was no killing of T cells, only reduction in proliferation. The inhibitory effect of the macrophages correlated with the spontaneous formation of rosettes between the macrophages and the T cell clone. The number of rosettes forming a single layer of T cells around the macrophages, but not the number of rosettes with multiple layers of cells, was reciprocally related to the amount of Ia expression. The results suggest that macrophages bear a surface structure that influences and modulates the growth of T cells.

Washed cells, from ascitic fluid, which contained predominantly polymorphonuclear leucocytes from casein treated donor mice, induced accelerated amyloid formation in untreated syngeneic recipient animals. A similar transfer model, with lymph node cell suspension, was ineffective. Amyloidogenesis was completely blocked by colchicine treatment of the donors while treatment of the recipients had no effect. A casein induced amyloidogenic stimulus was transferred from nude C3H mice to their normal litter-mates. When the order was reversed, no amyloidosis occurred in the nude recipients. These experiments indicate the possible involvement of two cells in the biphasic process of casein induced murine amyloid formation: the polymorphonuclear leucocyte in the first phase and the T lymphocyte in the second.

Dimethyl sulfoxide was administered intravenously for 60 days to twenty mice with casein-induced amyloidosis. Partial or total disappearance of amyloid deposits occurred in all treated animals. The urine of these animals contained a substance from which amyloid fibrils could be synthesized. A control group of mice with casein-induced amyloidosis given saline injections showed massive amyloid deposition in the liver and in the spleen at the end of the experiment. Neither the urine of these mice nor the urine of normal control mice treated with dimethyl sulfoxide contained substances from which amyloid fibrils could be synthesized. It is our assumption that dimethyl sulfoxide treatment of mice with amyloidosis resulted in a break up of amyloid fibres into small subunits which were excreted in the urine.

In vitro experiments have shown that the amyloid degrading activity of amyloidotic sera could be restored by ascorbic acid, citric acid and by EDTA. It was therefore decided to test the influence of Vitamin C on experimental murine amyloidosis. Amyloidosis was induced during 14 days in three groups of 60 animals each. The first group received Vitamin C in the drinking water, as 3.5% solution, throughout the entire experimental period. Vitamin C was given to the second group after the induction of amyloidosis, while the control group received water alone. On the tenth, 17th, and 20th post induction days, 15 mice of each group were sacrificed. Their spleens were examined for the presence of amyloid. On the 17th day no amyloid was found in nine mice (out of 15) of the first group and in eight of the second. Small deposits were observed in five and three animals respectively. However, in the control groups giant deposits of amyloid were found in ten out of 15 animals. Amyloid degrading activity (ADA) of murine serum was examined in untreated, amyloidotic and Vitamin C treated animals. In healthy animals the ADA is unaffected by Vitamin C. In amyloidotic mice which have very low ADA initially, the addition of Vitamin C significantly increases the ADA. These results may possibly indicate that the in vitro effect of Vitamin C on amyloidotic sera is also expressed in an in vivo experimental model.

Insulin, calcitonin and parathyroid hormone subjected to one of two procedures-acidification and heating or incubation with mouse kidney lysosomal extracts-assumed a nonbranching fibrillar structure, 7 to 10 nm in diameter. The preparations showed green birefringence after Congo red staining. The in vitro synthesis from different hormonal polypeptides of fibrils, fulfilling the criteria for the identification of amyloid, indicates that these criteria are related to conformational rather than to compositional properties, and suggests that these hormones may provide the subunit of the amyloid formed in the corresponding endocrine organs.

Acute, ischemic renal failure was induced in rats by clamping of the renal vessels for 1 h. Following the termination of the ischemic period 5 g/kg of dimethyl sulfoxide (DMSO) were administered intravenously as a 20% solution in saline. Control animals received normal saline. There were not deaths among the DMSO-treated animals. Urine flow began within 15 min of DMSO infusion. 24 h after the experiment the mean blood urea was 73 +/- (SEM) 14 mg/100 ml (n = 29). All the control rats died during the week following the experiment. The mean blood urea at 24 h was 276 +/- 18 mg/100 ml (n = 20). In 10 additional animals perfusion of the kidney with DMSO prior to the closure of renal vessels protected the organ from ischemic damage. These experiments have a bearing on the therapeutic approach to ischemic renal failure in man, and on preservation methods of donor kidneys for transplantation.

ADA of human serum was demonstrated and investigated with an agar gel diffusion technique using amyloid-impregnated agar plates. Sera of 20 healthy adults, 40 patients with AA-amyloidosis, and 86 nonamyloidotic patients were tested. The presence of an ADF, showing enzymatic properties and strongly bound to albumin, was demonstrated in normals and amyloidotic and nonamyloidotic patients. ADA in the serum of amyloidotic and cirrhotic patients was markedly decreased due to the presence of an inhibitor of ADF. ADA of amyloidotic sera was restored to normal by EDTA, citric acid, and ascorbic acid. The ADA of 16 FMF patients and four of 34 patients with rheumatoid arthritis without amyloidosis was intermediate between normal and amyloidotic values, indicating the presence of lADF at low concentrations in these patients. These findings suggest that amyloid is a normal protein metabolite, possibly with a high metabolic turnover. Accumulation of amyloid may be caused by decrease of the ADA of the serum by its inhibitor, rather than by accelerated production.

Renal ischemia was produced in rats by clamping of the renal artery for 1 h. Upon termination of the ischemic period a 20% solution of DMSO (5 g/kg b.w.) was given intravenously to 33 rats. Eighteen control animals received normal saline. All DMSO-treated animals survived while all control animals died within the subsequent seven days. At 24 h following the experiment, the mean blood urea of the control rats was 254 mg/100 m1 and the mean plasma creatinine 7.2 mg/100 m1. By contrast, the DMSO-treated rats had a mean blood urea of 69 mg/100 m1 and plasma creatinine of 1.6 mg/100 m1. In 17 animals the kidney was perfused with DMSO prior to the closure of the renal artery. All these rats survived the procedure and showed near normal kidney function at 24 h. The renal artery was clamped for 60 min in ten dogs. Five dogs received DMSO (3 g/kg b.w.) and the other five received an equivalent dose of normal saline. Three weeks later a contralateral nephrectomy was performed. Renal function was normal in the DMSO-treated dogs. One control dog died of uremia, in the remaining four a transient renal failure was observed. These experiments in two different animals highlight the protective effect of DMSO on the ischemic kidney when the drug is administered after the ischemic period.

Amyloid was obtained in recipient mice by implantation into their peritoneal cavity of a dialysis bag containing spleen cells obtained from donor mice which were treated with casein for 6 days and while no amyloid was found in their implanted spleens. The transplantations were performed with 2 cell systems, one containing whole spleen suspension and the other washed cells. Amyloid was obtained in the recipient mice within 6 days after the implantation and in a more massive quantity than in mice treated by casein for a similar period.

A patient with nephrotic syndrome was found to have amyloidosis secondary to an otherwise asymptomatic Crohn's disease. Resection of a major portion of the affected bowel and long-term colchicine therapy were followed by a complete clinical remission of the nephrotic syndrome, most probably due to a significant resolution of amyloidosis. The combination of resection of affected bowel segments, together with long-term colchicine therapy may offer a better prognosis than either method alone.

In systemic amyloidosis, the rare instances of recovery following the successful treatment of a predisposing disease present a challenge in the management of an otherwise fatal disorder 1,2. Notwithstanding, experimental endeavor has been directed largely toward unravelling the nature of amyloid and its pathogenesis rather than the biological mechanism by which this fibrillar protein may be removed from the tissues 3. The following experiments indicate that normal human serum contains a heat-stable component capable of degrading amyloid in vitro.Procedure. In principle, one portion of a standard suspension of water-soluble amyloid 4 was incubated with two portions of human serum in a test tube for 2 hr at 37°. Following incubation the precipitate obtained by centrifugation for 30 min in a cooled PC-2 Sorvall Centrifuge at 15,000 rpm was collected, twice washed in cold saline, and recentrifuged as above, resuspended in normal saline, and its total protein content determined by the Biuret method at 555 nm. ...

Amyloidosis was induced by casein injections in mice allocated to glucose, purina and casein dietary regimens. Amyloid was not found in the glucose fed mice. By contrast, amyloid was present in the spleen of purina fed animals and in the spleen, liver and kidney of those fed casein. It seems therefore that adequate protein intake is essential for the consummation of an amyloidogenic stimulus.

The natural clinical course of four patients with systemic amyloidosis was favourably altered by continuous colchicine therapy. One patient had primary amyloidosis, and the other three suffered from amyloidosis of familial Mediterranean fever. All had a nephrotic syndrome, and one showed features of intestinal malabsorption. The institution of colchicine therapy was followed by a gradual remission of the nephrotic syndrome, a rise of serum albumin to normal values, a slight improvement of renal function, and regression of the intestinal malabsorption. This pattern has remained steady during an observation period of 30 months.