Review: A review on classical and atypical scrapie in caprine: Prion protein gene polymorphisms and their role in the disease.

Scrapie is a naturally occurring transmissible spongiform encephalopathy in sheep and goat. It has been known for ~250 years and is characterised by the accumulation of an abnormal isoform of a host-encoded prion protein that leads to progressive neurodegeneration and death. Scrapie is recognised in two forms, classical and atypical scrapie. The susceptibility to both types of scrapie is influenced by polymorphisms of the prion protein gene (PRNP). Sheep susceptibility or resistance to classical scrapie is strongly regulated by the polymorphisms at codons 136, 154 and 171 of the PRNP. The genetic role in atypical scrapie in sheep has been defined by polymorphisms at codons 141, 154 and 171, which are associated with different degrees of risk in the occurrence of the ovine disease. Progress has been achieved in the prevention of scrapie in sheep due to efficient genetic breeding programmes based on eradication and control of the disease. In Europe, the success of these programmes has been verified by applying eradication and genetic selection plans. In general terms, the ovine selection plans aim to eliminate and reduce the susceptible allele and to enrich the resistant allele ARR. During outbreaks all susceptible animals are slaughtered, only ARR/ARR resistant rams and sheep and semi-resistant females are preserved. In the occurrence of scrapie positive goats a complete cull of the flock (stamping out) is performed with great economic loss and severe risk of extinction for the endangered breeds. The ability to select scrapie-resistant animals allows to define new breeding strategies aimed to boost genetic progress while reducing costs during scrapie outbreaks. Allelic variants of PRNP can be protective for caprine scrapie, and the knowledge of their distribution in goats has become very important. Over the past few years, the integration of genetic information on goat populations could be used to make selection decisions, commonly referred to as genetic selection. The objective of this review was to summarise the main findings of polymorphisms of the caprine prion protein (PrP) gene and to discuss the possible application of goat breeding schemes integrating genetic selection, with their relative advantages and limitations.

Beyond palliative mastectomy in inflammatory breast cancer--a reassessment of margin status.

BACKGROUND: Inflammatory breast cancer is a locally advanced tumor with an aggressive local and systemic course. Treatment of this disease has been evolving over the last several decades. The aim of this study was to assess whether current therapies, both surgical and chemotherapeutic, are providing better local control (LC) and overall survival (OS). We also attempted to identify clinical and pathologic factors that may be associated with improved OS, disease-free survival (DFS), and LC. METHODS: A 25-year retrospective review performed at the City of Hope National Medical Center identified 90 patients with the diagnosis of inflammatory breast cancer. RESULTS: Of the 90 patients identified with inflammatory breast cancer, 33 received neoadjuvant therapy (NEO) consisting of chemotherapy followed by surgery with radiation (n = 26) and without radiation (n = 7). Fifty-seven patients received other therapies (nonNEO). Treatments received by the nonNEO group consisted of chemotherapy, radiation, mastectomy, adrenalectomy, and oophorectomy, alone or in combination. The median follow-up was 28.9 months for the NEO group and 17.6 months for the nonNEO group. Borderline significant differences in the OS distributions between the two groups were found (P = .10), with 3- and 5-year OS for the NEO group of 40.0% and 29.9% and for the nonNEO group of 24.7% and 16.5%, respectively. DFS and LC were comparable in the two groups. Lower stage was associated with an improved OS (P < .05). The 5-year OS for stage IIIB was 30.9%, compared to 7.8% for stage IV. In those patients with stage III disease who were treated with mastectomy and rendered free of disease, margin status was identified by univariate analysis to be a prognostic indicator for OS (P < .05). The 3-year OS, DFS, and LC for patients with negative margins were 47.4%, 37.5%, and 60.3%, respectively, compared to 0%, 16.7%, and 31.3% in patients with positive margins. CONCLUSIONS: This study suggests that in patients with inflammatory breast cancer and nonmetastatic disease, an aggressive surgical approach may be justified with the goal of a negative surgical margin. Achievement of this local control is associated with a better overall outcome for this subset of patients. The ability to obtain negative margins may further identify a group of patients with a less aggressive tumor biology that may be more responsive to other modalities of therapy.

Oligonucleotides as modulators of cancer gene expression.

The delineation of gene function has always been an intensive subject of investigations. Recent advances in the synthesis and chemistry of oligonucleotides have now made these molecules important tools to study and identify gene function and regulation. Modulation of gene expression using oligonucleotides has been targeted at different levels of the cellular machinery. Triplex forming oligonucleotides, as well as peptide nucleic acids, have been used to inhibit gene expression at the level of transcription; after binding of these specific oligonucleotides, conformational change of the DNA's helical structure prevents any further DNA/protein interactions necessary for efficient transcription. Gene regulation can also be achieved by targeting the translation of mRNAs. Antisense oligonucleotides have been used to down-regulate mRNA expression by annealing to specific and determined region of an mRNA, thus inhibiting its translation by the cellular machinery. The exact mechanism of this type of inhibition is still under intense investigation and is thought to be related to the activation of RNase H, a ribonuclease that is widely available that can cleave the RNA/DNA duplex, thus making it inactive. Another well-characterized means of interfering with the translation of mRNAs is the use of ribozymes. Ribozymes are small catalytic RNAs that possess both site specificity and cleavage capability for an mRNA substrate, inhibiting any further protein formation. This review describes how these different oligonucleotides can be used to define gene function and discusses in detail their chemical structure, mechanism of action, advantages and disadvantages, and their applications.

Primary lymphoepithelioma-like carcinoma of the lung in a child. Report of an Epstein-Barr virus-related neoplasm.

Lymphoepithelioma-like carcinoma (LEC), an undifferentiated carcinoma with pronounced lymphocytic infiltration, often is seen in the nasopharynx as well as in other areas. But such primary pulmonary lung neoplasms in children are rare, and we present the first reported case of primary pulmonary LEC in a child.

Local recurrence in breast cancer: implications for systemic disease.

BACKGROUND: Recurrence in breast carcinoma follows a pattern of growth marked by local, regional, or widespread dissemination. Local recurrence may be the harbinger of systemic disease or failure of local control. Delineation of these processes may have implications in treatment. METHODS: A retrospective review found 1,171 patients with stages I and II breast cancer from 1978 to 1990 treated at the City of Hope Medical Center. RESULTS: Twenty-seven percent (n = 313) of patients developed recurrences. These were classified as local, including chest wall and regional nodes (n = 40), local and distant (n = 63), and distant (n = 210). Mean follow-up was 60 months. Multivariate analysis demonstrates tumor size was not different between the three groups, but the presence of positive lymph nodes was: local = 51%, local and distant = 78%, and distant = 64%. The disease-free interval was longest in the local group (42 months) versus the local and distant group (23 months) and distant group (39 months). Median survival was calculated from the time of recurrence: local = 90 months, local and distant = 26 months, and distant = 16 months. CONCLUSIONS: A group of patients with local recurrence have improved survival and do not develop distant disease. This group may benefit from aggressive surgical treatment to control local disease. These data suggest that a subset of breast tumors can act locally aggressive without metastatic potential.

Increased specific binding of insulin-like growth factor-I in healing cutaneous wounds.

Insulin-like growth factor-I is a polypeptide hormone structurally related to insulin. It is a potent mitogen that promotes growth and differentiation in many tissues. A role for insulin-like growth factor-I in wound healing is suggested by its rapid rise in levels and increased insulin-like growth factor-I messenger RNA expression in tissue after wounding. We designed our study to characterize possible changes in insulin-like growth factor-I receptor binding during wound healing. Surgical wounds created on the abdominal skin of anesthetized New Zealand White rabbits were either left open or closed primarily. Size- and weight-matched specimens were harvested at wounding time (day 0), and at 1, 4, 7, 38, and 50 days after wounding. Preliminary experiments showed that the greatest difference in specific binding occurred between day 0 and day 7. (125)I-insulin-like growth factor-I binding studies were performed on frozen tissue specimens and autoradiography was performed and analyzed by computerized densitometry. Scatchard analysis of the binding data showed a single class of insulin-like growth factor-I binding sites whose affinity that is, binding constant (K(d) = 0.6 x 10(-9)) did not change significantly over time; in contrast there was a threefold increase in the number of receptors per milligram tissue in day 7 wound tissue versus normal skin harvested at day 0 (17.3 +/- 2.6 x 10(10) versus 4.7 +/- 2.5 x 10(10), respectively, p < 0.05). Binding inhibition experiments showed that (125)I-insulin-like growth factor-I binding was most specific to insulin-like growth factor-I with insulin-like growth factor-I > insulin-like growth factor-II > insulin. This increase in binding was due to upregulation of insulin-like growth factor-I receptors rather than increased levels of insulin-like growth factor-I binding protein as less than 20% of the threefold increase in binding at day 7 could be attributed to insulin-like growth factor-I binding protein in membrane-free extracts. The presence of specific, high-affinity insulin-like growth factor-I receptors in the skin and their upregulation at day 7 after wounding suggest that insulin-like growth factor-I plays an important role during wound healing.

Cytogenetic studies on commercial hexane solvent.

Commercial hexane is a solvent mixture of six-carbon isomers, consisting principally of n-hexane, 3-methylpentane, methylcyclopentane and 2-methylpentane. The potential of commercial hexane to produce chromosome aberrations was evaluated in both an in vitro assay using Chinese hamster ovary (CHO) cells and an in vivo cytogenetics assay using Sprague-Dawley rats. The CHO cells were exposed to media containing commercial hexane at concentrations of 0.014-0.42 microliters ml-1 in the presence and absence of an S-9 activation mixture. Cellular toxicity was observed at the higher dose levels, but no increase in chromosome aberrations was observed in either the non-activated or S-9-activated systems. For the in vivo cytogenetics assay, rats were exposed nose-only for 6 h per day for 5 consecutive days to commercial hexane vapor at target concentrations of 900, 3000 and 9000 ppm. Bone marrow cells were collected at 6 and 24 h after the midpoint of the last exposure. Metaphase cells were examined microscopically for chromosome aberrations. No statistically significant increases in aberrant cells were observed in the commercial hexane-exposed animals of any dose group at either of the bone marrow harvest times. In conclusion, commercial hexane did not produce chromosomal mutations under the conditions of these studies.

Effects of ursodeoxycholic acid therapy for liver disease associated with cystic fibrosis.

The hydrophilic bile acid ursodeoxycholic acid (UDCA) has recently been shown to improve indexes of liver function in adult patients with various liver diseases. The clinical and biochemical responses to UDCA administration (10 to 15 mg/kg body weight per day) were therefore investigated in nine patients with cystic fibrosis and evidence of liver disease. All patients were receiving pancreatic enzymes and taurine supplementation. Liver function tests were done and serum bile acid concentrations and biliary bile acid composition were determined before and during UDCA therapy; fat balance studies and fecal bile acid excretion were carried out before and 6 months after UDCA treatment. After 2 months of bile acid therapy, biliary bile acid composition was enriched in UDCA from approximately 5% before treatment to 25%, at the expense of cholic and chenodeoxycholic acids, thus making the pool more hydrophilic. This enrichment is lower than that reported for adults with chronic liver diseases. Serum concentrations of UDCA increased significantly but variably. UDCA became the predominant fecal bile acid excreted (12% to 67%), indicating a variable absorption of the administered bile acid. Liver function improved in all patients after 2 to 6 months of therapy, although the degree of improvement (aspartate aminotransferase, -34%; alanine aminotransferase, -41%; gamma-glutamyltranspeptidase, -41% alkaline phosphatase, -19%) was lower than that observed in adults with chronic liver diseases. Mean coefficient of fat absorption and growth rate were, on average, unaffected by UDCA therapy, although an improvement was noted for three patients with greater severity of steatorrhea. The study indicates that UDCA can be used safely in this patient population but that higher doses of UDCA may be of greater benefit in the treatment of the liver disease associated with cystic fibrosis.

Genetic differences in cystic fibrosis patients with and without pancreatic insufficiency. An Italian collaborative study.

To determine the number and frequency of mutations that occur at the cystic fibrosis locus (CF), we have examined the allele and haplotype frequencies of eight polymorphic DNA markers linked to CF in 163 Italian patients who were sub-divided according to their clinical presentations. The distribution of haplotypes for the tightly linked polymorphisms KM.19 and XV-2c differ significantly between patients with and those without pancreatic insufficiency. The haplotype found most commonly in CF chromosomes occurs much more frequently in pancreatic insufficient than in pancreatic sufficient patients. Among the 19 pancreatic sufficient patients, 6 (31.6%) show at least one copy of the rare KM.19 = 1, XV-2c = 2 haplotype, as against 16 of 138 patients (11.6%) with pancreatic insufficiency. In addition, only 5 pancreatic sufficient patients (26.3%) are homozygous for the common 2.1 haplotype, as compared with 88 patients (63.8%) with pancreatic insufficiency. These findings support the hypothesis of allelic heterogeneity at a single locus in CF and suggest that different mutations underlie the presence or absence of pancreatic insufficiency in this disorders.

Prevention of cystic fibrosis in Italian families by DNA studies.

We performed a feasibility study of prenatal diagnosis in the Italian population by DNA analysis utilizing the probes: metD, metH, J3.11, KM.19 and XV-2c. With these probes, 118 out of 126 families (93.7%) were fully informative. We also tested part of the families with new additional tightly linked probes, E.9 and W3D1.4. With all the probes feasibility was complete in 44 out of 45 families (97.8%). In particular with a set of only 3 tightly linked probes, KM.19 + XV-2c + W3D1.4, 71% of the families were fully informative. We carried out 8 prenatal diagnoses, 4 of which with the polymerase chain reaction (PCR) for KM.19. These data show that these probes are highly informative and can be used for feasibility studies and prenatal diagnosis of CF in the Italian population.

Effect of taurine supplementation on fat and bile acid absorption in patients with cystic fibrosis.

Eleven children with cystic fibrosis (CF) and pancreatic insufficiency were given supplementation with taurine (30-40 mg/kg/day) for 2 months, while taking their usual dosage of enzymatic therapy. One patient dropped out of the study because she developed severe constipation. In the other 10 patients, urinary taurine excretion (88 +/- 30.1 mg/m2s.a./24 h) was similar to that of controls (86.2 +/- 6 mg/m2s.a./24 h) before taurine and increased markedly after supplementation (618.2 +/- 79.97 mg/m2s.a./24 h), indicating efficient intestinal absorption. Their coefficient of fat absorption was 81.2 +/- 2.3% and increased significantly after taurine (91.3 +/- 1.13%; p less than 0.01); the area under the curve of plasma triglyceride postprandial levels (1 +/- 0.1 mg X min/ml) also increased significantly after taurine (1.4 +/- 0.3 mg X min/ml; p less than 0.05), showing values very similar to those of controls. Conversely, no change was observed in the serum postprandial levels of glycocholic acid: the maximum postprandial peak before (1.2 +/- 0.3 mumol/l) and after taurine (1 +/- 0.1 mumol/l) remained significantly lower than in controls (2.4 +/- 0.3 mumol/l); p less than 0.01 and p less than 0.001, respectively. Mean total fecal bile acid (BA) excretion was 10.24 +/- 2.15 mg/kg/day before taurine and 12.8 +/- 4.27 mg/kg/day after taurine (normal pediatric values, 2.91 +/- 1.1 mg/kg/day); however, in the individual patients we found a variable trend, four of them showing a net increase in fecal BA excretion.(ABSTRACT TRUNCATED AT 250 WORDS)

The management of enzymatic therapy in cystic fibrosis patients by an individualized approach.

We evaluated nutritional status, pulmonary impairment, nutritional intake, and fat absorption in 73 cystic fibrosis (CF) patients to identify the primary factor(s) influencing growth. In general, the growth pattern in our patients was satisfactory since 60/73 were not underweight. When caloric intake is greater than or equal to 95% of RDA, wasting does not occur regardless of the degree of malabsorption, dietary fat content, or lung involvement. In the group of patients who consume less than the RDA, underweight is related to the severity of pulmonary disease; indeed, 11/13 underweight patients have a chest x-ray score over 15. Steatorrhea is well controlled in most patients; only 11 of 73 show a fat excretion greater than 25% of fat intake. The daily number of capsules of Pancrease varies from 4 to 57. The amount of Pancrease to be given was individualized to meet each patient's requirements using fat balance studies to determine the necessary daily Pancrease dose, then distributing the total dose in proportion to the fat content of each meal.

Concentrations of semi-synthetic penicillins in the plasma and in the expectoration, administered by means of intermittent vein perfusion.

We report the levels of concentration of ampicillin, dicloxacillin, and carbenicillin reached in the blood and in the expectoration following the administration of these drugs by rapid venous infusion, once every 24 h. The concentration of ampicillin in the blood serum varied from 150 to 180 micrograms/ml at the end of the infusion and from 30 to 3 micrograms/ml 4 afterwards and the dicloxacillin concentration from 150 to 120 micrograms/ml, and from 24 to 6 micrograms/ml. The concentration of ampicillin in purulent expectoration was 5-7 micrograms/ml and that of dicloxacillin 2.5-4 micrograms/ml. The concentration of carbenicillin in the plasma varied from 1,040 to 130 micrograms/ml, and in the expectoration it was around 15 micrograms/ml. Several cases of acute and chronic lung and bronchial diseases caused by bacteria have been treated by means of venous infusion once every 24 h and results were excellent.

Complement (C3), nutrition, and infection.

Complement (C(3)) was determined and related to various parameters of nutritional status and past infectious disease experience in a group of 53 rural preschool children in North India. Mean complement level was 25% lower than in an age-matched European reference population. Low complement (C(3)) levels were associated mainly with children who were both stunted and wasted, as well as with those who had experienced frequent purulent skin infections in the past.