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We employed DNA sequence variation at two mitochondrial (control region, COI) regions from 212 individuals of Galaxias platei (Pisces, Galaxiidae) collected throughout Patagonia (25 lakes/rivers) to examine how Andean orogeny and the climatic cycles throughout the Quaternary affected the genetic diversity and phylogeography of this species. Phylogenetic analyses revealed four deep genealogical lineages which likely represent the initial division of G. platei into eastern and western lineages by Andean uplift, followed by further subdivision of each lineage into separate glacial refugia by repeated Pleistocene glacial cycles. West of the Andes, refugia were likely restricted to the northern region of Patagonia with small relicts in the south, whereas eastern refugia appear to have been much larger and widespread, consisting of separate northern and southern regions that collectively spanned most of Argentinean Patagonia. The retreat of glacial ice following the last glacial maximum allowed re-colonization of central Chile from nonlocal refugia from the north and east, representing a region of secondary contact between all four glacial lineages. Northwestern glacial relicts likely followed pro-glacial lakes into central Chilean Patagonia, whereas catastrophic changes in drainage direction (Atlantic --Pacific) for several eastern palaeolakes were the likely avenues for invasions from the east. These mechanisms, combined with evidence for recent, rapid and widespread population growth could explain the extensive contemporary distribution of G. platei throughout Patagonia.

Changes in lake and stream habitats during the growth and retreat of Pleistocene glaciers repeatedly altered the spatial distributions and population sizes of the aquatic fauna of the southern Andes. Here, we use variation in mtDNA control region sequences to infer the temporal dynamics of two species of southern Andean fish during the past few million years. At least five important climate events were associated with major demographic changes: (i) the widespread glaciations of the mid-Pliocene (c. 3.5 Ma); (ii) the largest Patagonian glaciation (1.1 Ma); (iii) the coldest Pleistocene glaciation as indicated by stacked marine delta(18)O (c. 0.7 Ma); (iv) the last southern Patagonian glaciation to reach the Atlantic coast (180 ka); and (v) the last glacial maximum (LGM, 23-25,000 years ago). The colder-water inhabitant, Galaxias platei, underwent a strong bottleneck during the LGM and its haplotype diversity coalesces c. 0.7 Ma. In contrast, the more warm-adapted and widely distributed Percichthys trucha showed continuous growth through the last two glacial cycles but went through an important bottleneck c. 180,000 years ago, at which time populations east of the Andes may have been eliminated. Haplotype diversity of the most divergent P. trucha populations, found west of the Andes, coalesces c. 3.2 Ma. The demographic timelines obtained for the two species thus illustrate the continent-wide response of aquatic life in Patagonia to climate change during the Pleistocene, but also show how differing ecological traits and distributions led to distinctive responses.

Peyronie's disease can best be described as a localized connective tissue disorder that primarily affects the tunica albuginea of the penis. The disease may be attributed to repetitive vascular trauma that initiates an inflammatory process and ultimately leads to the formation of a fibrous penile plaque. The plaque consists mainly of collagen and can significantly alter penile anatomy and function. Patients with Peyronie's disease will most often present with penile curvature, pain on erection, a palpable nodule most commonly located on the dorsal shaft of the penis, and erectile dysfunction. There is no definitive treatment for Peyronie's disease and the treating physician has many options. They may wait for spontaneous resolution of the plaque, choose medical therapy (which includes both oral and intralesional regimens), or opt for surgical management. The main purpose of this article is to discuss the advances in medical therapy for Peyronie's disease, in particular intralesional injection of interferon-alpha-2b (IFN-alpha-2b). Several studies have concluded that IFN-alpha-2b can be an effective modality of treatment and that many patients placed on a regimen of IFN-alpha-2b experienced a significant reduction in penile curvature, diminished pain with erection, and decreased size of the plaque. Further clinical studies are currently being undertaken to determine the precise quantity and frequency of administration of IFN-alpha-2b that is most effective with the least amount of side effects.

▪ Abstract Recent progress on the use of near-field scanning optical microscopy (NSOM) to characterize organic thin film materials is extensively reviewed. NSOM is leading to important new information on the morphology and spatially resolved optical properties of a variety of materials, complementing more widely available methods for thin film analysis. Materials described in this review include polymer thin films, molecular aggregates, molecular crystals, molecular semiconductor heterojunctions, biological materials, and molecular mono-, bi-, and multi-layer films.

Synopsis An epithelium is important for integrity, homeostasis, communication and co-ordination, and its development must have been a fundamental step in the evolution of modern metazoan body plans. Sponges are metazoans that are often said to lack a true epithelium. We assess the properties of epithelia, and review the history of studies on sponge epithelia, focusing on their homology to bilaterian epithelia, their ultrastructure, and on their ability to seal. Electron micrographs show that adherens-type junctions are present in sponges but they can appear much slighter than equivalent junctions in other metazoans. Fine septae are seen in junctions of all sponge groups, but distinct septate junctions are only known from Calcarea. Similarly, all sponges can have collagenous sheets underlying their epithelia, but only homoscleromorphs are established to have a distinct basal lamina. The presence of most, but not all, gene families known to be involved in epithelial development and function also suggests that sponge epithelia function like, and are homologous to, bilaterian epithelia. However, physiological evidence that sponge epithelia regulate their internal environment is so far lacking. Given that up to six differentiated epithelia can be recognized in sponges, distinct physiological roles are expected. Recognition that sponges have epithelia challenges the perception that sponges are only loose associations of cells, and helps to relate the biology and physiology of the body plan of the adult sponge to the biology of other metazoans.

Raman spectra of Mn2(CO)10 and Re2(CO)10 have been studied to 27 and 98 kbar respectively, and the infrared (IR) spectrum of Re2(CO)10 to 30 kbar at ambient temperature. Both materials undergo a first-order structural phase transition at high pressure (Mn at approximately 8 kbar, Re at approximately 5 kbar) which is accompanied by dramatic changes in all regions of their vibrational spectra. These data are interpreted in terms of a change of molecular geometry from D4d to D4h. In the new high-pressure phases the M to carbonyl backbonding is increased significantly for the axial but not the equatorial carbonyls. The molecular torsion is implicated in the phase change but is not thought to drive it.

The so-called 'valence transition' in EuPd2Si2 has been observed using energy-dispersive synchrotron X-ray powder diffraction at elevated pressures and is centred at 8 kbar. The estimated increase in valence at the transition is 0.2, and is associated with crossover of 4f and 6d/s bands.

Using synchrotron energy-dispersive X-ray powder diffraction (EDXRPD) the authors have shown that K2SnBr6 transforms at pressures of 14 kbar and above from the parent monoclinic cell to a cubic structure of symmetry Fm3m, which is stable to 120 kbar. A different phase appears to exist above 120 kbar.

The structural behaviour of ammonium metavanadate, NH4VO3, under high pressures has been studied to 65 kbar using energy-dispersive synchrotron X-ray powder diffraction, and to 106 kbar by FTIR methods, in a diamond anvil cell. A reversible crystalline-to-disordered phase transition was found at 49 kbar. The transition is thought to be due to relative slipping of the vanadate chains parallel to their axes, the product being disordered, possibly amorphous, rather than crystalline because the process is hindered and the solid prevented from attaining periodicity by hydrogen bonding to ammonium ions.

Changes in lake and stream habitats during the growth and retreat of Pleistocene glaciers repeatedly altered the spatial distributions and population sizes of the aquatic fauna of the southern Andes. Here, we use variation in mtDNA control region sequences to infer the temporal dynamics of two species of southern Andean fish during the past few million years. At least five important climate events were associated with major demographic changes: (i) the widespread glaciations of the mid-Pliocene (c. 3.5 Ma); (ii) the largest Patagonian glaciation (1.1 Ma); (iii) the coldest Pleistocene glaciation as indicated by stacked marine delta(18)O (c. 0.7 Ma); (iv) the last southern Patagonian glaciation to reach the Atlantic coast (180 ka); and (v) the last glacial maximum (LGM, 23-25,000 years ago). The colder-water inhabitant, Galaxias platei, underwent a strong bottleneck during the LGM and its haplotype diversity coalesces c. 0.7 Ma. In contrast, the more warm-adapted and widely distributed Percichthys trucha showed continuous growth through the last two glacial cycles but went through an important bottleneck c. 180,000 years ago, at which time populations east of the Andes may have been eliminated. Haplotype diversity of the most divergent P. trucha populations, found west of the Andes, coalesces c. 3.2 Ma. The demographic timelines obtained for the two species thus illustrate the continent-wide response of aquatic life in Patagonia to climate change during the Pleistocene, but also show how differing ecological traits and distributions led to distinctive responses.

A spectroscopic system used for the calibration of pressure using the ruby R-line method has been designed and interfaced to a BBC model B microcomputer. The methodology of the real-time software design is detailed including flow diagrams for the three main programs employed in the system. The software includes both ambient and high-pressure data acquisition and analysis programs. Suggestions are made for the application of the software system to other experimental tasks and also to other compatible microcomputers.

We have previously reported a method for labeling epidermal growth factor (EGF) with technetium-99m and have shown that 99mTc-EGF localized in EGF receptor (R) positive intracerebral C6EGFR rat gliomas following intratumoral (i.t.) injection of the radioligand. In the present study, we have evaluated the potential use of 99mTc-EGF as a tumor targeting agent after systemic administration to Fischer rats bearing intracerebral implants of C6EGFRgliomas. Radiolocalization was determined following intravenous (i.v.) or intracarotid (i.c.) injection with or without hyperosmotic mannitol induced disruption of the blood-brain barrier (BBB-D). As determined by gamma-scintillation counting, 4 h after i.c. injection of 99mTc-EGF, 0.34% of the injected dose per gram (% ID/g) was localized in C6EGFR tumors. which expressed 10(5)-10(6) EGFR sites per cell, compared to 0.07% ID/g in animals bearing C6 wildtype gliomas, which do not express EGFR. The corresponding tumor to brain ratios were 5.6 and 1.6, respectively. Tumors could be visualized by external gamma-scintigraphy in rats bearing C6EGFR but not C6 wildtype gliomas, thereby establishing that radiolocalization was dependent upon receptor expression. Intracarotid administration of 99mTc-EGF significantly increased tumor uptake compared to i.v. injection (0.34 vs 0.14% ID/g, p0.04). BBB-D disruption, followed by i.c. injection of 99mTc-EGF, however, did not significantly enhance tumor uptake compared to i.c. injection without BBB-D (0.45% vs 0.34% ID/g, p0.1). The uptake of 99mTc-EGF was approximately 4-9% ID/g in the liver and 12-20% ID/g in the kidneys after i.c. or i.v. administration. External gamma-scintigraphy of regions of interest over the liver and kidneys revealed that approximately 70-80% of the whole body radioactivity accumulated in these organs, and only 0.47-0.83% in the tumor following i.v. or i.c. administration of 99m9Tc-EGF. Our study has demonstrated that EGF can be used as a specific targeting agent for EGFR (+) rat brain tumors. However, it is unlikely that systemic injection of EGF-based bioconjugates can deliver sufficient amounts of the ligand to brain tumors for therapeutic purposes and direct delivery by means of either intratumoral injection or a variant of it such as convection enhanced delivery will be required.

The in vivo uptake of dodecahydro-closo-dodecaborate derivatives substituted with phosphate- and bisphosphonate groups was evaluated in two different experimental tumor model systems and compared to other boronated and non-boronated compounds. These phosphorous-containing boron clusters may have potential for use in boron neutron capture therapy, a chemoradiotherapeutic form of cancer treatment. Using the F98 rat glioma as a brain tumor model in syngeneic Fischer rats, there was selective tumor uptake of the phosphate derivative with 21.5 micrograms boron/g tumor versus 5.2 micrograms/g normal brain and a tumor:blood ratio of 2.7. However, this compound was toxic to test animals and lethal at relatively low doses. The uptake of the bisphosphonate by the murine K8 osteosarcoma was approximately 18 micrograms boron/g tumor with a T:Bl ratio of 7.6 and a tumor:bone ratio of 1.5. This compound was non toxic to the test animals. The results indicate that phosphate- and bisphosphonate derivatives of dodecahydro-closo-dodecaborate may have potential for BNCT of gliomas and osteosarcomas, respectively.

A boronated derivative of dequalinium, a delocalized lipophilic cation (DLC), was synthesized as a potential boron carrier for the selective targeting of mitochondria in malignant versus benign cells for boron neutron capture therapy (BNCT), a binary modality for the treatment of cancer. This agent, designated DEQ-B, was taken up and retained in vitro in the KB, F98, and C6 tumor cell lines but not in the normal epithelial cell line CV1. DEQ-B was also less toxic in the latter cell line at lower exposure concentrations The uptake, retention, and toxicity profiles of DEQ-B are comparable to those of the non-boronated DLCs, dequalinium, MKT 077, RH 123, and tetraphenylphosphonium chloride. Our results suggest that the synthesis and further evaluation of boronated DLCs as potential delivery agents for BNCT is warranted.

Purpose. To evaluate the significance of marked, acute swelling in patients after percutaneous sclerosis of low-flow vascular malformations, as a predictor of both prolonged recovery and likelihood of therapeutic effect.¶Materials and methods. In 22 patients who underwent percutaneous ethanol sclerosis of low-flow vascular malformations, we compared the incidence of prolonged recovery and lasting therapeutic effect between those patients with and without marked soft-tissue swelling following the procedure.¶Results. Five patients exhibited marked swelling after sclerosis. Four of these five had causes of prolonged recovery. These four recovered and all five eventually had marked therapeutic effect. Seventeen patients did not meet criteria for severe swelling. Only one of these patients had prolonged recovery. Eighteen of the 22 total patients had therapeutic effect. All 4 of the 22 total patients who had no therapeutic effect were in the group without marked swelling.¶Conclusions. Marked soft-tissue swelling, which occurs after percutaneous sclerosis of vascular malformations, is both a predictor of prolonged recovery and high likelihood of therapeutic effect.

L ow-flow vascular malformations, such as venous or mixed malformations, can cause a variety of medical problems related to pain, compression or invasion of adjacent structures, limited range of motion, bleeding, consumptive coagulopathy, and cosmetic deformity [1-4]. Treatment of these lesions is often problematic. Surgical resection, medical therapy, and transarterial embolization therapy have all had limited suc

Our goal was to compare the lengths of hospitalization and the perinatal outcomes of triplet pregnancies managed with either outpatient or inpatient third-trimester bed rest.Thirty-two triplet pregnancies in which outpatient bed rest was prescribed (April 1993 to April 1996) were compared with a historic cohort of 34 triplets (January 1985 to March 1993) in which routine hospitalization was undertaken in the third trimester. Length of hospitalization and maternal and neonatal outcome parameters were compared between groups.Maternal inpatient hospital days were significantly reduced for the group managed as outpatients, but combined maternal and neonatal hospitalization was similar between groups. The mean gestational age at delivery was 1 week greater in the hospitalized cohort (33.5+/-2.8 vs 32.5+/-2.8, respectively; p=0.16), and average birth weight was correspondingly greater in hospitalized cases (1942 gm vs 1718 gm, p0.005). Neonatal lengths of stay were similar between groups, reflecting earlier postnatal discharge in the outpatient era of this study. Preeclampsia occurred with greater frequency in the outpatient group (31.3% vs 8.8%, p=0.02), and the neonatal complication of intraventricular hemorrhage occurred more commonly in this cohort as well (10/96 vs 1/102, p=0.004). All other maternal and neonatal complications were similar between groups.Reduction in the length of hospitalization attributable to outpatient management was limited to the maternal length of stay. It is possible that the observed maternal and neonatal complications in the outpatient group may have been related to less rigorous bed rest. We would suggest that the differences noted in preeclampsia, birth weight, and intraventricular hemorrhage support prospective evaluation of bed rest in triplet pregnancy.

Stressful events have long been acknowledged as important risk factors for suicidal behavior. Although suicide research has generally focused on less severe stressful events, a long-standing vulnerability for suicidal behavior may be a sequela of prolonged traumatic stressors. The present paper discusses the relationship between prolonged traumatic stress and subsequent suicidality by reviewing studies that have examined suicidal behavior in relationship to child abuse and combat trauma. Traumatic stress is conceptualized according to a person-environment interactional paradigm, and this paradigm is used to discuss the characteristics of traumatic events, recovery environments, and individuals that may contribute to subsequent suicidality.

The gene for epidermal growth factor receptor (EGFR) is amplified or overexpressed in high-grade gliomas but is low or undetectable in normal brain. Recently, there has been increasing interest in using epidermal growth factor (EGF)-based bioconjugates as targeting agents for brain tumors. In the present study, we have investigated the potential use of boronated EGF as a delivery agent for boron neutron capture therapy, which is based on the capture reaction that occurs when 10B, a stable isotope, is irradiated with low-energy thermal neutrons. A fourth generation starburst dendrimer was boronated and linked to EGF using heterobifunctional reagents. Either wild-type or EGFR gene transduced C6 glioma cells (C6EGFR), which expressed 10(5)-10(6) receptor sites/cell, were stereotactically implanted into the right cerebral hemisphere of Fischer rats. Four weeks later, the rats received either i.v. or intratumoral (i.t.) injection of 131I-labeled boronated starburst dendrimer (BSD) or BSD-EGF. The biodistribution of 131I-BSD-EGF and 131I-BSD was studied by means of whole-body scintigraphy, autoradiography, and gamma scintillation counting. Following i.t. injection of 131I-BSD-EGF, 21.8% of the injected dose per gram tissue (% ID/g) was localized in C6EGFR tumors at 24 h and 16.3% at 48 h compared to 5 and 1.3% ID/g in C6 wild-type tumors, respectively, and 0.01 and 0.006% ID/g, respectively, for i.v. injected animals at the corresponding times. In contrast, following i.t. injection of BSD-EGF, only 0.01-0.1% ID/g was localized in the liver and spleen at 24 and 48 h compared to 5-12% ID/g following i.v. injection. Our data indicate that direct i.t. injection can selectively deliver BSD-EGF to EGFR-positive gliomas and suggest that intracerebral administration may be the most effective way for delivering EGF-based bioconjugates to EGFR-positive brain tumors.

Omenn syndrome comprises a rare form of combined immunodeficiency with TH2-type features of eosinophilia and elevated IgE. Previous studies have led to reports of restricted heterogeneity in the T lymphocyte repertoire, and in vitro cloned T lymphocytes have been shown to produce IL-4 and IL-5. We hypothesized that (1) T cell receptor beta V(D)J DNA sequence analysis would confirm and further define the putative restricted heterogeneity, and (2) increased production of IL-4 and IL-5 should be found in nonstimulated T lymphocytes, if the molecular pathogenesis of Omenn syndrome is an uncontrolled TH2 state. We report the results of molecular analyses of T lymphocytes from an untreated 3-month-old patient. Oligoclonal T cell receptor beta variable gene usage was found. Sequence analysis revealed sets of identical V(D)J sequences, each in-frame, with apparently normal N-diversification and no obvious antigen combining site motif. From fresh, nonstimulated lymphocytes, proinflammatory TH1 cytokines could be detected, but TH2 cytokines could not, so that a simple TH1/TH2 paradigm cannot explain the eosinophilia and elevated IgE in Omenn syndrome. Our studies fully document for the first time at the molecular level that clonally expanded populations of T lymphocytes are present in Omenn syndrome.

Boron neutron capture therapy (BNCT) is based on the nuclear capture reaction that occurs when 10B, a stable isotope, is irradiated with low energy neutrons to produce high linear energy transfer (LET) alpha particles and recoiling 7Li nuclei. In order for BNCT to be successful in treating cancer, approximately 10(9) boron atoms must be delivered per tumor cell to sustain a lethal 10B, (n,a) 7Li capture reaction. In the present study, we have produced and characterized a bispecific antibody (BsAbB8), which was reactive with both human glioma and melanoma cell lines, as well as with a variety of polyhedral borane anions (PBA). The affinity constants (KA) of BsAb-B8 with D-54 MG and M21 cells were 3.49 and 2.57 x 10(8) M-1, respectively, which were almost identical to those of the parental mAb 9.2.27 with these cell lines. In vivo tumor localizing properties were studied in nude mice bearing subcutaneous xenografts of the D-54 MG glioma. Following intravenous injection of 131I-labeled BsAb-B8, 3.4 +/- 0.2% of the injected dose/g was detected in the tumor at 24 hours, and then slowly declined to 2.0 +/- 0.4% at 96 hours compared to 1.34 +/- 0.07% and 0.03 +/- 0.01%, respectively, for normal mouse IgG. Based on the assumption that all the tumor cell antigenic receptor sites could be saturated, the following calculations have been carried out. The maximum concentration of BsAb-B8 that could be delivered to 1 g of D-54 MG glioma cells would be 99.6 micrograms, which could bind 71.7 ng of a PBA. However, since at least 500 x more boron would be required per gram of tumor to sustain a lethal 10B (n,a) 7Li capture reaction, a macromolecule containing -10(3)-10(4) boron atoms rather than a low molecular weight PBA would be required to deliver this amount. Such boron containing macromolecules have been synthesized by us, and future studies should provide information on the feasibility of using them in combination with BsAb-B8 to deliver the requisite amount of 10B.

As clinicians include an immunologic evaluation in their assessment of recurrent fetal loss among otherwise asymptomatic women, the diagnosis of PAPS will be uncovered with greater frequency. Our understanding of the underlying pathophysiology of PAPS is critical if we are to propose safe and rational therapies for these patients. It appears as though prostaglandin metabolites are implicated directly in the processes that culminate in this unique, localized vasculopathy; and research is actively progressing with this focus in mind. For the present, we should look critically at the available treatments to be sure that the rationale for use is consistent with current evidence and that the margin of fetal and maternal safety justifies their use. To date, only low-dose aspirin appears to alter prostaglandin metabolites favorably and is thus, emerging as our safest and most efficacious treatment.

Epithelial tissue — the sealed and polarized layer of cells that regulates transport of ions and solutes between the environment and the internal milieu — is a defining characteristic of the Eumetazoa. Sponges, the most ancient metazoan phylum [1], [2], are generally believed to lack true epithelia [3], [4], [5], but their ability to occlude passage of ions has never been tested. Here we show that freshwater sponges (Demospongiae, Haplosclerida) have functional epithelia with high transepithelial electrical resistance (TER), a transepithelial potential (TEP), and low permeability to small-molecule diffusion. Curiously, the Amphimedon queenslandica sponge genome lacks the classical occluding genes [5] considered necessary to regulate sealing and control of ion transport. The fact that freshwater sponge epithelia can seal suggests that either occluding molecules have been lost in some sponge lineages, or demosponges use novel molecular complexes for epithelial occlusion; if the latter, it raises the possibility that mechanisms for occlusion used by sponges may exist in other metazoa. Importantly, our results imply that functional epithelia evolved either several times, or once, in the ancestor of the Metazoa.

That part of the field of single-crystal vibrational spectroscopy which is devoted to acquisition of well-proven assignments in terms of symmetry species is first placed within the wider context of solid state spectroscopy as a whole. Theoretical and practical factors which limit the size of crystal with which meaningful polarisation data can be obtained are then considered. Finally, brief summaries are given of selected areas of recent significant activity: chain and layer structures, silicates, and complexes with donor ligands.

A comparative study of antibody titres to nine common viruses has been carried out in hepatitis B surface (HBs) antigen-positive and -negative chronic active liver disease. The results show that increased titres of antibody to morbilli virus by complement fixation and to rubella by haemagglutination inhibition are found in HBs antigen-negative but not in HBs antigen-positive chronic active liver disease. There was a significant association of increased morbilli but not of rubella virus antibody titres with the presence of high-titre nuclear antibodies (ANA) but no association with smooth-muscle antibody or the presence of HLA-B8.

A summary account is given of the phase transitions found at high pressure for several inorganic carbonyl and cyanide complexes: M(CO)6, (M = Cr, Mo, W); Re(CO)5Br; M2(CO)10, (M = Mn, Re) and MnRe(CO)10; Hg(CN)2; K2M(CN)4, (M = Zn, Cd, Hg); and K3Cu(CN)4. The structures of some of the phases have been deduced using group theoretical methods.

The aims were to understand and to learn how to control potentially destructive stresses which limit the performance of anvils in high pressure optical and X-ray cells. The calculations show that the largest compressive and shear stresses are near the working face of the anvil and, hence, that plastic flow will begin there, as has been observed. The largest tensile stresses are at the base, above the unsupported light port. Since diamond, a brittle material, is liable to failure in tension, these stresses are potentially destructive. The largest principal tensile stress is in a hoop direction: consequently diamond anvils are liable to basal failure by radial cracking, with ring cracking from tensile radial stresses important also. This type of failure has been observed in diamond anvil cells. In the light of these results, mechanisms of anvil failure are discussed and illustrated with photographs. Attention is drawn to the importance of fatigue as a cause of failure in diamond.

IR and Raman spectra of MCl2(meso-2,3-diaminobutane), (M = Pd, Pt), have been recorded down to liquid nitrogen temperature or lower. It is shown that correlation coupling occurs between closely spaced hydrogen-bonded pairs of molecules, which form a “super molecule,” but not between all eight molecules in the unit cell. The lattice mode region is also understood in outline on the basis of motions of the “super molecules” Methyl torsional modes appear to be near 140 cm−1.

Ultrahigh temperature sterilized canned puddings occasionally exhibit spoilage in the form of a dramatic loss of viscosity or thinning. Studies on a concentrated fraction of spoiled pudding indicate that thinning was due to a heat-resistant amylase. The concentrate was obtained by centrifugation and ultrafiltration of the thinned pudding. Ultrafiltration characteristics of the active agent indicate a molecular weight of 1–30 × 104 daltons. The agent attacked starch with a decrease in iodine-binding capability and an increase in reducing units. Treatment of the concentrate with proteolytic enzymes decreased enzymatic activity by 50%; treatment with sodium ethylene diaminetetraacetate decreased activity by 80%. The levels of starch and pH of the spoiled puddings were suitable for action of the amylase, and the enzyme was quite active at normal and elevated room temperatures.

The α-amylase of the thermophile Bacillus stearothermophilus 1518 was used as a model enzyme to examine the heat resistance of a bacterial amylase at ultrahigh temperature in a starch-based pudding. When heated in the laboratory pudding at 143°C for the equivalent of 22.2 set, approximately 26% of the initial amylolytic activity was retained. The presence or absence of individual ingredient groups (starch, caseinate-nonfat dry milk, oilemulsifiers, salts, or sucrose) of the pudding had no significant effect on amylase heat resistance. A combination of any two of the starch, caseinate-nonfat dry milk, or oil-emulsifier ingredients were found to be important for thermostability. The amylase of the mesophile Xanthomonas campestris 13957–2 exhibited similar thermal inactivation characteristics.

Potassium nitrate (KNO3) has seven polymorphs in the pressure range 0-4.0 GPa. The authors have studied it at room temperature as a function of pressure up to 9.3 GPa and have confirmed the structure of phase IV previously refined by neutron diffraction at 0.36 GPa. The compressibility measured in the range 0.3-9.3 GPa is found to be anisotropic with the axial compression ratios a:b:c=1.0:0.64:0.50. The relative merits of X-rays and neutrons for high-pressure studies are discussed.

Modified PA3679 agar (MPA3679A) was formulated as a plating medium to provide improved recovery of Clostridium sporogenes Putrefactive Anaerobe (PA) 3679 spores. A comparative study of MPA3679A and two currently used plating media, Yeast extract agar (YEA), and Peptone trypticase agar (PTA), showed that MPA3679A was superior for the recovery of heat activated and heat stressed spores. Further, when this medium was altered for use as an inoculated pack subculture medium, recovery of severely heat stressed spores was superior to that in the previously recommended PA3679 agar, also known as T-Best.

The optical problems associated with infrared spectroscopy at very high pressures in a diamond anvil cell are considered and the main limitations identified. The principal difficulty is the conflict between optical requirements, which indicate the need for relatively large unsupported areas of diamond, and mechanical requirements which work conversely. A simple refracting beam condenser is described and the problems of coupling it to spectrophotometers are indicated.

Phase transitions have been observed in mercury (II) cyanide near 2.5, 89, 19 and 60 kbar. The I/II transition appears to be of second order with the structure of phase II closely related to that of the parent molecular type. Using Landau theory, three possible structures have been identified for the new phase II, of which S24 is marginally better in accord with the evidence. A major reconstruction of the lattice occurs at the II/III transition; the coordination number of mercury appears to increase to four, and the structure becomes covalently bonded, rather than molecular. Phase IV has a spectrum consistent with it having the cubic anti-cuprite structure adopted at STP by Zn(CN)2 and Cd(CN)2. Above 60 kbar, brown polymeric Hg(CN)2V is formed irreversibly. It has a single IR absorption

Raman spectra of CH3Hg (X=Cl,Br,I) have been studied as a function of pressure using diamond anvil cells. Phase transitions were discovered in the chloride at 1.5+or-0.3 and 5.9 kbar, with an almost immediate further transition near 6 kbar to a phase stable to at least 40 kbar. CH3HgBr shows a single transition at 12.5 kbar. Soft modes were found for all three materials. That for the bromide was followed by change of temperature as well as of pressure. The crystal structure of CH3HgBr was found to be like that of the chloride, but of a different space group (P421m, Z=4), allowing slight nonlinearity of the C-Hg-Br skeleton. On the basis of this structural evidence a phase diagram is proposed. A very narrow (about 0.1 kbar) phase in CH3HgCl may be incommensurate. Preliminary studies of CH3HgI show that its behaviour parallels that of its congeners, but that the crystallography is different in detail.

Infrared reflectance spectra are reported for oriented single crystals of MAMC and PAMC with the electric vector parallel to the anionic sheets for temperatures from 50 to 295K. Single-crystal Raman spectra were also obtained at similar temperatures. The main features of the spectra, particularly for the ambient temperature phases, are assigned with the aid of a factor group analysis. This phase for MAMC, although orthorhombic, behaves spectroscopically as pseudo-tetragonal, but PAMC is plainly orthorhombic. Modes above 260 cm-1 are attributed to cation internal modes, including torsions. The phase III (tetragonal) to phase IV (monoclinic) transition is distinguished in the Raman spectra by disappearance of an intense broad features at about 35 cm-1/.

Clostridium perfringens spores were injured by ultrahigh-temperature treatment at 105 C for 5 min. Injury was manifested as an increased sensitivity to polymyxin and neomycin. Since many of the survivors could not germinate normally the ultrahigh-temperature-treated spores were sensitized to and germinated by lysozyme. Polymyxin reportedly acts upon the cell membrane. Neomycin may inhibit protein synthesis and has surface-active properties. Injured spores were increasingly sensitive to known surface-active agents, sodium lauryl sulfate, sodium deoxycholate, and Roccal, a quaternary ammonium compound. Injured spores sensitive to polymyxin and neomycin also were osmotically fragile and died during outgrowth in a liquid medium unless the medium was supplemented with 20% sucrose, 10% dextran, or 10% polyvinylpyrrolidone. The results suggested that a spore structure destined to become cell membrane or cell wall was the site of injury. Repair of injury during outgrowth in the presence of protein, deoxyribonucleic acid, ribonucleic acid and cell wall synthesis inhibitors was consistent with this hypothesis.

The heat resistant lipase of Pseudomonas spp. MC50 hydrolyzed coconut oil, corn oil, butter oil and olive oil. Lipase activity was maximum at 1% corn oil. The effects of pH and temperature on lipase activity varied with the substrate. The pH optima were in the range pH 8–9; the temperature optima were in the range 35–40°C. Of several emulsifiers tested, four supported significant lipase actiivity, and three supported no lipase activity and may have inhibited the lipase. Emulsifier concentration influenced lipase activity. All stabilizers tested supported lipase activity; above 0.36% stabilizer concentration had no effect.

Pseudomonas spp. MC50 produced an extra-cellular lipase that was extremely heat resistant at 100–150°C when heated in water or emulsions. The D-values ranged from 40 min at 100°C to 84 sec at 150°C. The zD-vallue was 36°C. When heated in water, the lipase exhibited greatest survival at pH 8.5. Below pH 6.5, survival was less than 10% of that at pH 8.5. Survival of lipase heated in emulsions was affected somewhat by the type of oil, corn oil concentration, and type of emulsifier. Type of stabilizer or stabilizer concentration had little effect on lipase survival. Lipase treated with ethylenediaminetetraacetate (EDTA) was fully heat resistant in water; survival declined when lipase was heated in CaCl2 solutions of 3–120 mM.

Raman spectra of NaNO2 have been studied as a function of hydrostatic pressure to 40 kbar at 295 and 348 K. Slight changes in slope of mode frequency versus pressure plots support the view that a structural anomaly exists at 9 ± 1 kbar. The absence of qualitative changes in the Raman spectra allow the space group of NaNO2 IV to be specified as one of P1, P2, B2, Pm or Bm. The Raman spectrum of NaNO3 has been studied to 87 kbar. The changes observed are fully consistent with a second-order transition to a phase with symmetry C63v, as indicated by previous X-ray work, although the transition is sluggish.

The effect of pressure at low temperature (166.8K) upon the R1 and R2 lines of ruby has been investigated for the first time to establish a calibration for use in high-pressure/low-temperature work. A reinvestigation of the behaviour of R1 and R2 at ambient temperatures and at pressures up to ca 70 kbar supports previous work on the calibration under hydrostatic conditions but shows that in a 4:1 methanol:ethanol mixture conditions become nonhydrostatic at lower pressures (ca 50 kbar) than claimed (ca 100 kbar). The importance of monitoring both R1 and R2 is emphasised as their relative shifts are sensitive indicators of the presence, and approximate magnitude, of non-hydrostatic stress components. It is shown that although changes in half-bandwidths are also associated with development of shear stress, their use in estimating gradients is extremely hazardous and can indicate values greatly in excess of the known shear strength of the material.