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Candida albicans is the single, most frequently isolated human fungal pathogen. As with most fungal pathogens, the factors which contribute to pathogenesis in C. albicans are not known, despite more than a decade of molecular genetic analysis. Candida albicans was thought to be asexual until the discovery of the MTL loci homologous to the mating type (MAT) loci in Saccharomyces cerevisiae led to the demonstration that mating is possible. Using Candida albicans mutants in genes likely to be involved in mating, we analysed the process to determine its similarity to mating in Saccharomyces cerevisiae. We examined disruptions of three of the genes in the MAPK pathway which is involved in filamentous growth in both S. cerevisiae and C. albicans and is known to control pheromone response in the former fungus. Disruptions in HST7 and CPH1 blocked mating in both MTLa and MTL(alpha) strains, whereas disruptions in STE20 had no effect. A disruption in KEX2, a gene involved in processing the S. cerevisiae pheromone Mf(alpha), prevented mating in MTL(alpha) but not MTLa cells, whereas a disruption in HST6, the orthologue of the STE6 gene which encodes an ABC transporter responsible for secretion of the Mfa pheromone, prevented mating in MTLa but not in MTL(alpha) cells. Disruption of two cell wall genes, ALS1 and INT1, had no effect on mating, even though ALS1 was identified by similarity to the S. cerevisiae sexual agglutinin, SAG1. The results reveal that these two diverged yeasts show a surprising similarity in their mating processes.

This paper uses patent data from colonial Australia to provide an estimate of comparative Anglo- American inventive activity at the end of the nineteenth century. These data confirm the traditional belief of a widening inventive gap in this period. The paper argues that much of this gap can be accounted for by each nation’s factor endowment and demand pattern. The results, however, also indicate that tariffs may have had a role to play as well. The paper concludes by highlighting the need for further understanding of the ways in which competition, tariffs, and perceptions of security can impact on technological creativity.

Medulloblastoma is an uncommon tumour in the adult population. Maximum surgical resection followed by craniospinal irradiation with a posterior fossa boost is the standard treatment. We report the case history of an adult with medulloblastoma and severe kyphoscoliosis. The unusual anatomy of the patient posed a technical challenge to the oncologist and the physicist in planning the craniospinal radiotherapy. A shaped spinal field matched to a parallel opposed pair of shaped head fields was used. The technique used in treating this patient was made possible with the use of a multileaf collimation and verification with an electronic portal imaging device. The patient remains well with no sign of relapse 4 years after treatment.

This ash study investigated the beneficial use of municipal waste combustion combined ash from the H-POWER facility in Oahu. These uses were grouped into intermediate cover for final closure of the Waipahu landfill, daily cover at the Waimanalo Gulch Landfill, and partial replacement for aggregate in asphalt for road paving. All proposed uses examine combined fly and bottom ash from a modern waste-to-energy facility that meets requirements of the Clean Air Act Amendments for Maximum Achievable Control Technology.

As part of the ongoing Candida albicans Genome Project, we have constructed a complete sequence-tagged site contig map of chromosome 7, using a library of 3840 clones made in fosmids to promote the stability of repeated DNA. The map was constructed by hybridizing markers to the library, to a blot of the electrophoretic karyotype, and to a blot of the pulsed-field separation of the SfiI restriction fragments of the genome. The map includes 149 fosmids and was constructed using 79 markers, of which 34 were shown to be genes via determination of function or comparison of the DNA sequence to the public databases. Twenty-five of these genes were identified for the first time. The absolute position of several markers was determined using random breakage mapping. Each of the homologues of chromosome 7 is approximately 1 Mb long; the two differ by about 20 kb. Each contains two major repeat sequences, oriented so that they form an inverted repeat separated by 370 kb of unique DNA. The repeated sequence CARE2/Rel2 is a subtelomeric repeat on chromosome 7 and possibly on the other chromosomes as well. Genes located on chromosome 7 in Candida are found on 12 different chromosomes in Saccharomyces cerevisiae.

This project to develop a high-performance bridge steel was intended to avoid susceptibility of the steel to weld heat-affected-zone cracking and therefore minimize the requirement for preheat, and to increase its fracture toughness at service temperatures. Previous studies by the Lehigh University Center for Advanced Technology for Large Structural Systems have suggested that a Cu-Ni steels with the following composition was an excellent candidate for such a bridge steel: C/0.070; Mn/1.50; P/0.009; S/0.005; Si/0.25; Cu/1.00; Ni/0.75; Cr/0.50; Mo/0.50; V/0.06; Cb/0.010. To confirm that observation, 227-kg heats of the candidate steel were melted and processed to 25- and 50-mm-thick plate by various thermomechanical practices, and the weldability and mechanical properties determined. To evaluate the feasibility of reduced alloy content, two 227-kg heats of a lower hardenability steel were melted with C reduced to 0.06, Mn to 1.25, and Mo to 0.25 and similarly processed and tested. The results indicate that the steels were not susceptible to hydrogen-induced weld-heat-affected-zone cracking when welded without preheat. Jominy end-quench tests of the higher-hardenability steel indicate that a minimum yield-strength of 690 MPa should be readily attainable in thicknesses through 50 mm and marginally at 100 mm. The toughness of the steel readily met AASHTO specificationsmore » for Zone 3 in all conditions and thicknesses, and may be sufficiently tough so that the critical crack size will minimize fatigue-crack-extension problems.« less

Candida albicans strain WO-2 was isolated as a spontaneous derivative of the white-opaque switching strain WO-1. The electrophoretic karyotype of WO-2 lacks two bands which are found in the parent. These bands correspond to one homologue of chromosome 7 and to a translocation product containing parts of chromosomes 6 and 5. Probing a blot of the karyotype demonstrated that the genetic material in these bands had been lost, yielding an aneuploid strain. UV-irradiation experiments showed that auxotrophs due to mutation in genes located in this region predominated, supporting the conclusion that WO-2 is partially haploid. WO-2 contained about 10% of its genome in the haploid state, and it grew with a doubling time of about twice that of its parent. However, it was able to undergo both the yeast-to-hyphal transition and the white-opaque transition. Hence, these processes do not require perfect diploidy.

Background International standard adjuvant radiotherapy regimens following primary surgery for early breast cancer have historically delivered a high total dose (50Gy) in 25 small daily doses (fractions) over 5 weeks, however randomised trials, including START, indicate that a lower total dose delivered in fewer, larger fractions (Fr) is likely to be at least as safe and effective (START Trialists' Group, Lancet 2008 & Lancet Oncol 2008). With patients remaining at risk of local relapse for many years, information on long-term outcomes is needed to provide confidence in clinical practice. Here, we report 10-year follow-up of the UK START Trials testing 13- and 15-Fr regimens in terms of local cancer control and late adverse effects. Methods Between 1999 and 2002, 4451 women with completely excised invasive breast cancer (T1-3, N0-1, M0) were randomised after primary surgery to comparisons of 50Gy in 25Fr over 5 weeks vs 41·6Gy or 39Gy in 13Fr over 5 weeks (START A), or 50Gy in 25Fr over 5 weeks vs 40Gy in 15Fr over 3 weeks (START B). Women were eligible if aged over 18 years and did not have an immediate surgical reconstruction. Protocol-specified principal endpoints were local-regional (LR) tumour relapse and late normal tissue effects. Analysis was by intention to treat. Findings Median follow-up in survivors is now 9.3 years in START A and 9.9 years in START B, with 139 LR relapses in START A and 95 in START B. In START A, the 10-year rate of LR relapse was 7.4% (95%CI 5.5–10.0) after 50Gy, 6.3% (95%CI 4.7–8.5) after 41·6Gy and 8.8% (95%CI 6.7–11.4) after 39Gy. In START B, the 10-year rate of LR relapse was 5.5% (95%CI 4.2–7.2) after 50Gy and 4.3% (95%CI 3.2–5.9) after 40Gy. Clinician assessments suggested lower 10-year rates of any moderate/marked late normal tissue effects after 39Gy (43.9%; 95%CI 39.3–48.7) and similar rates after 41.6Gy (49.5%; 95%CI 44.9–54.3) compared with 50Gy (50.4%; 95%CI 45.8–55.3) in START A and lower rates after 40Gy in START B (37.9%; 95%CI 34.5–41.5) compared with 50Gy (45.3%; 95%CI 41.7–49.0). From a planned meta-analysis of START A and the START pilot trial (Owen et al, Lancet Oncol 2006), the adjusted estimate of α/β value for tumour control was 3.5Gy (95% CI 1.2–5.7) and for late change in photographic breast appearance was 3.1Gy (95% CI 2.0–4.2). Interpretation Long-term follow-up confirms that breast cancer and the surrounding dose-limiting healthy tissues respond similarly to radiotherapy fraction size and thus that appropriately-dosed hypofractionated radiotherapy is safe and effective in treatment of patients with early breast cancer. 41·6Gy in 13Fr and 40Gy in 15Fr each appear comparable to 50Gy in 25Fr in terms of local-regional tumour control and late normal tissue effects. These results support the continued use of 40Gy in 15Fr as standard of care (UK NICE Guidance 2009) for women requiring adjuvant radiotherapy for early breast cancer. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr S4-1.

Candida albicans produces large amounts of the acyclic pentitol D-arabitol in culture and in infected animals and humans, and most strains also grow on minimal D-arabitol medium. An earlier study showed that the major metabolic precursor of D-arabitol in C. albicans was D-ribulose-5-PO4 from the pentose pathway, that C. albicans contained an NAD-dependent D-arabitol dehydrogenase (ArDH), and that the ArDH structural gene (ARD) encoded a 31-kDa short-chain dehydrogenase that catalyzed the reaction D-arabitol + NAD D-ribulose + NADH. In the present study, we disrupted both ARD chromosomal alleles in C. albicans and analyzed the resulting mutants. The ard null mutation was verified by Southern hybridization, and the null mutant's inability to produce ArDH was verified by Western immunoblotting. The ard null mutant grew well on minimal glucose medium, but it was unable to grow on minimal D-arabitol or D-arabinose medium. Thus, ArDH catalyzes the first step in D-arabitol utilization and a necessary intermediate step in D-arabinose utilization. Unexpectedly, the ard null mutant synthesized D-arabitol from glucose. Moreover, 13C nuclear magnetic resonance studies showed that the ard null mutant and its wild-type parent synthesized D-arabitol via the same pathway. These results imply that C. albicans synthesizes and utilizes D-arabitol via separate metabolic pathways, which was not previously suspected for fungi.

We assessed the exchange of Candida albicans among crew members during 10 Space Shuttle missions. Throat, nasal, urine and faecal specimens were collected from 61 crew members twice before and once after space flights ranging from 7 to 10 days in duration; crews consisted of groups of five, six or seven men and women. Candida albicans was isolated at least once from 20 of the 61 subjects (33%). Candida strains were identified by restriction-fragment length polymorphism (RFLP) after digestion by the endonucleases EcoRI and HinfI; further discrimination was gained by Southern blot hybridization with the C. albicans repeat fragment 27A. Eighteen of the 20 Candida-positive crew members carried different strains of C. albicans in the specimens collected. Possible transfer of C. albicans between members of the same crew was demonstrated only once in the 10 missions studied. We conclude that the transfer of C. albicans among crew members during Space Shuttle flights is less frequent than had been predicted from earlier reports.

The opportunistic fungal pathogen, Candida albicans, is diploid as usually isolated and has no apparent sexual cycle. Genetic analysis has therefore been very difficult. Molecular genetics has yielded important information in the past few years, but it too is hampered by the lack of a good genetic map. Using the well-characterized strain 1006 and strain WO-1, which undergoes the white-opaque phenotypic transition, we have developed a genomic restriction map of C. albicans with the enzyme SfiI. There are approximately 34 SfiI restriction sites in the C. albicans genome. Restriction fragments were separated by pulsed-field electrophoresis and were assigned to chromosomes by hybridization of complete and partial digests with known chromosome-specific probes as well as by digestion of isolated chromosomes. Telomeric fragments were identified by hybridization with a telomere-specific probe (C. Sadhu, M.J. McEachern, E.P. Rustchenko-Bulgac, J. Schmid, D.R. Soll, and J.B. Hicks, J. Bacteriol. 173:842-850, 1991). WO-1 differs from 1006 in that it has undergone three reciprocal chromosomal translocations. Analysis of the translocation products indicates that each translocation has occurred at or near an SfiI site; thus, the SfiI fragments from the two strains are similar or identical. The tendency for translocation to occur at or near SfiI sites may be related to the repeated sequence RPS 1, which contains four such sites and could provide homology for ectopic pairing and crossing over. The genome size of both strains is about 16 to 17 megabases, in good agreement with previous determinations.

The secreted aspartyl proteinase activity from Candida albicans is thought to be a potential virulence factor. Four laboratories have cloned a gene from C. albicans encoding this enzyme. When two of these genes sharing 77% homology at the DNA level are hybridized under conditions of high stringency to contour-clamped homogeneous electric field chromosome separations of four different strains, they label different chromosomes: chromosome 6 for SAP1 and chromosome R for SAP2. The existence of different genes for the two sequences was confirmed by polymerase chain reaction. Genomic Southern blots probed with the genes and washed at low stringency revealed several cross-hybridizing bands. Contour-clamped homogeneous electric field chromosome separations probed at low stringency indicated that there was a cross-hybridizing sequence on chromosome 3 in addition to those on chromosomes R and 6. The genes for the secreted aspartyl proteinase activity in C. albicans thus constitute a gene family which we have called the SAP family.

Pulsed-field gel electrophoresis was used to analyze several aspects of the genetics of Candida albicans. A restriction map of the genome of strain 1006 was prepared using the eight-base-pair specific enzyme SfiI. The previously determined genetic map was superimposed on this physical map. Preparation of a similar map for the white-opaque strain WO-1 demonstrated the presence of three reciprocal chromosomal translocations in this organism. Mapping the cloned genes for the extracellular aspartyl proteinase to the electrophoretic karyotype under different stringencies demonstrated that there are at least four genes homologous to both the cloned genes.

Epidemiologic studies in women with recurrent Candida vaginitis have been hampered in the past by the lack of a reproducible typing system. Several molecular probes have now been developed that have the ability to differentiate strains of Candida albicans and give reproducible results. In this investigation, 24 women with Candida vaginitis were studied in a longitudinal fashion for 30 days following short-course antifungal therapy. Seven women with either recurrent vaginitis or with multiple culture-positive sites with C. albicans were included in an epidemiological study. A total of 18 isolates of C. albicans (12 vaginal and six rectal) were typed utilizing restriction fragment length polymorphisms of rDNA. This technique was able to differentiate five different strains of C. albicans. Our epidemiologic study revealed that vaginal and rectal strains recovered from the same women were usually different. None of our patients had a similar vaginal and rectal strain prior to treatment, and only one patient had the same strain isolated from both the rectum and the vagina at the time of recurrence. On the other hand, we found that the same strain of C. albicans was initially and later recovered from the vagina in four of five women who failed treatment or developed recurrent vaginitis. These results suggest that recurrent episodes of C. albicans vaginitis, following short-course antifungal therapy, are often due to relapse of the original infecting strain and not due to autoinoculation from the rectum.(ABSTRACT TRUNCATED AT 250 WORDS)

11504 Background: Following interim results of the HERA study (2005) trastuzumab (T) was introduced as standard clinical practice three weekly for 18 cycles postchemotherapy (CT). Cardiac dysfuncti...

Candida albicans and Candida stellatoidea are two closely related imperfect yeasts. Some isolates characterized as C. stellatoidea are in fact C. albicans, while others differ with respect to virulence and to karyotype, containing extra small chromosomes. Experiments in this study allowed us to infer that a typical C. stellatoidea isolate, Y2360, has 12 chromosomes rather than the 7 previously shown for C. albicans. The majority of cloned sequences tested hybridized to analogous chromosomes in C. albicans and in C. stellatoidea, although there were exceptions, and a repeated element isolated as specific for C. albicans hybridized to most of the chromosomes of C. stellatoidea. Several genes tested hybridized to one of the smaller, C. stellatoidea-specific chromosomes as well as to a larger one. The arrangement of restriction enzyme sites around the gene was the same in both the large and small chromosomes. For ADE2 and LYS2, the arrangements were identical to those of a typical C. albicans strain, FC18, suggesting a high degree of sequence conservation between the two species. Spheroplast fusion and segregation experiments showed that the ADE2 genes on both the large and small chromosomes of C. stellatoidea are active, implying that the organism is functionally at least triploid for this gene and probably for any others duplicated on the smaller chromosomes.

LBA518 Background: The START Trials (ST-A and ST-B) test the hypothesis that breast cancer is as sensitive to fraction (Fr) size as late reacting normal tissues, with an a/β value of about 4Gy. Methods: The phase III randomised START Trials tested hypofractionated post-operative RT in women with completely excised invasive breast cancer (T1–3, N0–1, M0). Centres opted for either ST-A or ST-B. ST-A tested 50Gy in 25Fr (5 wks) vs 41.6Gy vs 39Gy, both in 13Fr (5 wks). ST-B tested 50Gy in 25Fr (5 wks) vs 40Gy in 15Fr (3 wks). Stratification was by centre, surgery and boost. The primary endpoint was local-regional (LR) relapse. Late normal tissue effects (NTE) were assessed by breast photographs, clinical examination and quality of life (QL) questionnaires. Survival analysis methods were used to estimate rates of relapse and NTEs, and hazard ratios (HR) (with 95%CI). Smoothed estimates of absolute differences in relapse rates were obtained from the rates in the 50Gy control arms and the HR. Results: 2236 (ST-A) and 2215 (ST-B) patients were recruited from 35 UK centres during 1999–2002. Median follow-up is 5.1 years (ST-A) and 6.0 years (ST-B). There were 93 LR relapses in ST-A (4.1% at 5 years, 3.2- 5.0%), with absolute differences in LR relapse rates at 5 years compared with 50Gy of 0.2% (−1.3%−2.6%) for 41.6Gy and 0.9% (−0.8%−3.7%) for 39Gy. The a/β estimate for tumour control was 5.0Gy (−2.7–12.7). In ST-B, there were 65 LR relapses (2.8% at 5 years, 2.1–3.5%), with an absolute difference in LR relapse rates at 5 years of −0.6% (−1.7%−0.9%) for 40Gy vs 50Gy. In ST-A the rate of mild/marked change in photographic breast appearance was lower in 39Gy vs 50Gy (HR 0.69, 0.52–0.91), and similarly for 40Gy vs 50Gy in ST-B (HR 0.83, 0.66–1.04). The a/β estimate for change in breast appearance was 3.1Gy (1.6–4.6). Rates of induration, telangiectasia and breast oedema were lower in 39Gy (ST-A) and 40Gy (ST-B) compared with the 50Gy arms. QL results were consistent with the clinical findings. Conclusions: The fractionation sensitivity of breast cancer is comparable to that of late reacting normal tissues, confirming the results of a recent pilot trial. These results support the use of hypofractionated RT schedules for early breast cancer. No significant financial relationships to disclose.

The southern highbush blueberry (Vaccinium, mostly corymbosum) cultivars Jubilee, Pearl River, and Magnolia and the rabbiteye cultivars Climax and Premier were stored for 4 weeks at 1-2 °C. Berries were held in pint “clam shell” plastic retail units and were evaluated weekly for physical and compositional quality. As groups, the rabbiteyes were higher in SSC, SSC/TA, glucose and fructose, anthocyanins, and malic, quinic, and succinic acids. `Jubilee' was the southern highbush and `Climax' the rabbiteye least affected by the storage. `Pearl River' and `Magnolia' were less firm and more shriveled than the other cultivars. `Magnolia' had the highest incidence of decay; decay was slight overall.

Many concepts of the nutritional value of fruit and vegetables generally accepted in the past, in the light of more knowledge, today are considered “misconceptions.” For example, the tomato, once considered poisonous, then shown edible, later proved to be a “good” food and a valuable source of minerals and vitamin C, today shows the potential for significant anti-cancer activity. Results of a 6-year study of the dietary habits of 47,000 men reported up to a 45% reduction in the incidence of prostate cancer of those who ate 10 or more servings per week of tomato-based products. Other misconceptions to be discussed include nightshade vegetables and arthritis, apples after meals to clean the teeth and gums, and “if a little is good for you, a lot must be better.” Today's nutritional ideas about many fruits and vegetables may become tomorrow's misconceptions as our knowledge of the composition (e.g., phytochemicals) of fruits and vegetables increases. Examples of this are include the use of muscadine pomace and the nutritive value of strawberries.

The delivery of radiotherapy to the young child can be a challenging process, particularly where the primary disease is well advanced, involves the central nervous system or requires involuntary immobilisation. Radiotherapy units often sedate children to overcome these problems, which may lead to suboptimal nutrition and sleep disruption. We have reviewed our own practice in preparing young children for radiotherapy and factors influencing use of sedation. Our practice encompasses providing radiotherapy from a paediatric unit, encouraging parents and children to stay until radiotherapy is accepted by the child, structured and unstructured play therapy, and timing radiotherapy to reflect the child's natural sleep pattern.

Thirteen rabbiteye cultivars were surveyed for postharvest berry rots during the 1992, 1993, and 1994 harvest seasons. Disease incidence and severity were low, with

Rabbiteye (Vaccinium ashei) blueberries were harvested in Mississippi and highbush (V. corymbosum) blueberries were harvested in Michigan. The berries were rapidly cooled to 5C after harvest and kept at this temperature for 48 h before being analyzed as fresh fruit or freezing for later analyses. Microstructural (light and scanning/transmission electron microscopy) and chemical (pectins, cellulose, hemicellulose, lignin, and fiber) evaluations were performed to evaluate differences between the two types of blueberries. Scanning electron micrographs showed that rabbiteye spp. have thicker epidermal and subepidermal cells than highbush spp. Transmission electron micrographs also showed that rabbiteye spp. have a thicker, more uniform cuticle layer than highbush spp. Rabbiteye spp. contained higher fiber and complex polysaccharides than highbush spp. Although, there were no differences in total pectins, rabbiteye berries had lower water soluble pectins and oxalate soluble pectins than highbush blueberries. Differences in polysaccharides and pectins between highbush and rabbiteye berries indicate that their cell wall components differ. These differences, along with the variation in subepidermal, epidermal and cuticle layers of the skin, provide valuable information to explain the textural differences between rabbiteye and highbush blueberries.

Rabbiteye blueberry (Vaccinium ashei) cultivars `Climax', `Premier', and Tifblue' were treated with gibberellic acid when 50% to 75% of the flowers of each were at stage 5 and again 10 days later. No known pollination stresses occurred during flowering, and the growing conditions were near optimum. First harvest yields from the gibberellic-acid-treated plants of each cultivar were significantly lower than the yields from nontreated controls. Gibberellic acid treatment essentially delayed commercial quantity production by an estimated 5 to 7 days for each cultivar; for the early ripening cultivars `Premier' and `Climax', this delay could mean lower yields of more profitable early berries in the Mississippi–Louisiana growing areas. Harvest-season total yields from treated plants were lower than the yields from nontreated plants of each cultivar. Using gibberellic acid as a routine cultural practice may not be necessary for small-scale growers when pollination stresses, such as frost damage to flowers, do not occur.

Three varieties of rabbit eye (Vaccinium ashei) blueberries (`Climax',, `Premier', and `Tifblue') were harvested in Mississippi and two varieties of highbush (v. corymbosum blueberries (`BlueCrop' and `Jersey') were harvested in Michigan. Each variety was harvested at three different locations as replications. The berries were rapidly cooled to 5°C after harvest, placed in 1-pint containers, and analyzed at 7-day intervals for 28 days with day 0 being 48 h after harvest. Shear, compression and puncture forces were higher for rabbiteye spp. than for highbush spp. `Bluecrop' blueberries showed the lowest shear force whereas, Climax, had the most shear force. Puncture force (skin toughness) was lower for `Bluecrop' and `Jersey' and higher for, Climax, There was an increase in shear force by all varieties with storage time. `Premier, and `Climax' had lower soluble solids, but they increased with storage time. `Jersey' had the highest pH and `Tifblue' the lowest. Although all varieties lost moisture with time, `Bluecrop' always had higher moisture. Mold growth varied with time; however, `Bluecrop' had a higher percentage of moldy berries throughout refrigeration. The percent decay was higher for highbush blueberries after 16 d of refrigeration. Rabbiteye's toughness and firmness give them a longer refrigerated shelf-life over highbush blueberries.

I wish to comment on the paper by Plowman & Doughty (1991). The authors describe an interesting method for cranio-spinal radiation using a PTB technique. They “believe such techniques will become standard practice”.

In addressing the subject of nondestructive evaluation of internal quality of horticultural crops, the establishment of an understanding of quality is needed at the outset. Dull (4) has defined nondestructive quality evaluation (NDQE) as “a gaining of meaningful information which can be used in making judgments, both positive and negative, about the degree of excellence of a food with out altering the physical and chemical properties of that food.” In order to make judgments about a specific quality situation, one must select specific physical and/or chemical properties to be measured. A list of those properties would include weight, diameter, titratable acidity, pH, total nitrogen and concentration of soluble solids, sucrose, glucose, fructose, malic acid, citric acid, chlorophyll, carotene, anthocyanins, dry matter, proteins, amino acids, fat, starch, cellulose, pectins, and hemicellulose.

This paper reports that the opaque and white phenotypes of Candida albicans constitute a true high-frequency reversible transition system. The rDNA restriction fragment and orthogonal field alternating gel electrophoresis profiles of opaque and white phenotypes are indistinguishable, and a genetic marker introduced into a white strain is present in all opaque derivatives of this strain. Opaque and white derivatives appear markedly different on a bismuth indicator medium and differ in a number of other respects. We have used bismuth medium to examine the spontaneous and temperature-induced frequencies of transition from opaque to white. The temperature-induced transition from opaque to white does not occur when opaque cells are held in water.

By using orthogonal-field alternating gel electrophoresis (OFAGE), field-inversion gel electrophoresis (FIGE), and contour-clamped homogeneous field gel electrophoresis (CHEF), we have clearly resolved 11 chromosomal bands from various Candida albicans strains. OFAGE resolves the smaller chromosomes better, while FIGE, which under our conditions causes the chromosomes to run in the reverse order of OFAGE, is more effective in separating the larger chromosomes. CHEF separates all chromosomes under some conditions, but these conditions do not often resolve homologs. The strains examined are highly polymorphic for chromosome size. Fourteen cloned Candida genes, isolated on the basis of conferral of new properties to or complementation of auxotrophic deficiencies in Saccharomyces cerevisiae, and three sequences of unknown function have been hybridized to Southern transfers of CHEF, FIGE, and OFAGE gels. Four sets of resolvable bands have been shown to be homologous chromosomes. On the basis of these data, we suggest that C. albicans has seven chromosomes. Genes have been assigned to the seven chromosomes. Two chromosomes identified genetically have been located on the electrophoretic karyotype.

Chromosomes from Cryptococcus neoformans, an encapsulated yeast pathogen, were separated by contour-clamped homogeneous field gel electrophoresis. Seven strains representing all four serotypes were studied. It was found that each strain had a unique, reproducible pattern of chromosome bands which could potentially be used for strain polymorphism studies. There were between 10 and 12 chromosomes in the strains studied, with an approximate genomic size of 15,000 to 17,000 kilobases. Chromosome separation also could be used to assign locations for cloned genes, and the ribosomal DNA genes were found on one of the larger C. neoformans chromosomes. The technique of electrophoretic karyotyping should be helpful for genetic and molecular investigations into the biology of C. neoformans.