Microbiome of Ceca from Broiler Chicken Vaccinated or Not against Coccidiosis and Fed Berry Pomaces

American cranberry (Vaccinium macrocarpon) and lowbush/wild blueberry (V. angustifolium) pomace are polyphenol-rich products having potentially beneficial effects in broiler chickens. This study investigated the cecal microbiome of broiler-vaccinated or non-vaccinated birds against coccidiosis. Birds in each of the two groups (vaccinated or non-vaccinated) were fed a basal non-supplemented diet (NC), a basal diet supplemented with bacitracin (BAC), American cranberry (CP), and lowbush blueberry (BP) pomace alone or in combination (CP + BP). At 21 days of age, cecal DNA samples were extracted and analyzed using both whole-metagenome shotgun sequencing and targeted-resistome sequencing approaches. Ceca from vaccinated birds showed a lower abundance of Lactobacillus and a higher abundance of Escherichia coli than non-vaccinated birds (p < 0.05). The highest and lowest abundance of L. crispatus and E. coli, respectively, were observed in birds fed CP, BP, and CP + BP compared to those from NC or BAC treatments (p < 0.05). Coccidiosis vaccination affected the abundance of virulence genes (VGs) related to adherence, flagella, iron utilization, and secretion system. Toxin-related genes were observed in vaccinated birds (p < 0.05) in general, with less prevalence in birds fed CP, BP, and CP + BP than NC and BAC (p < 0.05). More than 75 antimicrobial resistance genes (ARGs) detected by the shotgun metagenomics sequencing were impacted by vaccination. Ceca from birds fed CP, BP, and CP + BP showed the lowest (p < 0.05) abundances of ARGs related to multi-drug efflux pumps, modifying/hydrolyzing enzyme and target-mediated mutation, when compared to ceca from birds fed BAC. Targeted metagenomics showed that resistome from BP treatment was distant to other groups for antimicrobials, such as aminoglycosides (p < 0.05). Significant differences in the richness were observed between the vaccinated and non-vaccinated groups for aminoglycosides, β-lactams, lincosamides, and trimethoprim resistance genes (p < 0.05). Overall, this study demonstrated that dietary berry pomaces and coccidiosis vaccination significantly impacted cecal microbiota, virulome, resistome, and metabolic pathways in broiler chickens.

Effects of Vaccination Against Coccidiosis on Gut Microbiota and Immunity in Broiler Fed Bacitracin and Berry Pomace

Feeding practices have been found to influence gut microbiota which play a major role in immunity of poultry. In the present study, changes in cecal microbiota and humoral responses resulting in the 55 ppm bacitracin (BACI), 1% each of cranberry (CP1) and wild blueberry (BP1) pomace alone or in combination (CP+BP) feeding in broiler Cobb 500 vaccinated or not against coccidiosis were investigated. In the non-vaccinated group, no significant treatment effects were observed on performance parameters. Vaccination significantly affected bird's performance parameters particularly during the growing phase from 10 to 20 days of age. In general, the prevalence of coccidiosis and necrotic enteritis (NE) was reduced by vaccination (P < 0.05). BACI-treated birds showed low intestinal lesion scores, and both CP1 and BP1 feed supplementations reduced Eimeria acervulina and Clostridium perfringens incidences similar to BACI. Vaccination induced change in serum enzymes, minerals, and lipid levels in 21-day old birds while, levels of triglyceride (TRIG) and non-esterified fatty acids (NEFA) were higher (P < 0.05) in CP1 treated non-vaccinated group than in the control. The levels of NEFA were lower in BACI- and CP1-fed birds than in the control in non-vaccinated day 28 old birds. The highest levels of all estimated three immunoglobulins (IgY, IgM, and IgA) were found in the vaccinated birds. Metagenomics analysis of the cecal bacterial community in 21-day old birds showed the presence of Firmicutes (90%), Proteobacteria (5%), Actinobacteria (2%), and Bacteroidetes (2%). In the vaccinated group, an effect of BACI was noted on Proteobacteria (P = 0.03). Vaccination and/or dietary treatments influenced the population of Lactobacillaceae, Enterobacteriaceae, Clostridiaceae, and Streptococcaceae which were among the most abundant families. Overall, this study revealed that besides their beneficial effects on performance, alike bacitracin, berry pomaces in poultry feed have profound impacts on the chicken cecal microbiota and blood metabolites that could be influenced by vaccination against coccidiosis.

Detection of human JCPyV and BKPyV in diffuse large B-cell lymphoma of the GI tract

Previous studies have demonstrated that infection with human polyomavirus, such as JCPyV and BKPyV, might be associated with various human tumors. However, an association between human JCPyV and BKPyV infection and diffuse large B-cell lymphoma (DLBCL) has not been reported. The purpose of this study was to examine DLBCLs of the gastrointestinal tract for evidence of human polyomavirus infection. Nested PCR and DNA sequencing were employed for viral DNA detection and viral genotype identification. In addition, two viral proteins, the large tumor antigen (LT) and the major structural protein (VP1), were detected by immunohistochemistry (IHC). Human JCPyV and BKPyV DNA was detected in 14 out of 16 tissue samples (87.5%), whereby nine cases were infected with JCPyV and five cases were infected with BKPyV. Both archetypal and rearranged genotypes of JCPyV and BKPyV were detected in the tissues. LT was detected in 11 tissue samples (68.75%). However, VP1 was not detected in any of the tissue samples. The presence of human JCPyV and BKPyV DNA and protein in DLBCL tissues of gastrointestinal tract were first reported in this study. The current results provide evidence of a possible association between human JCPyV and BKPyV infection and DLBCL.

Detection of human JCPyV and BKPyV in diffuse large B-cell lymphoma of the GI tract

Previous studies have demonstrated that infection with human polyomavirus, such as JCPyV and BKPyV, might be associated with various human tumors. However, an association between human JCPyV and BKPyV infection and diffuse large B-cell lymphoma (DLBCL) has not been reported. The purpose of this study was to examine DLBCLs of the gastrointestinal tract for evidence of human polyomavirus infection. Nested PCR and DNA sequencing were employed for viral DNA detection and viral genotype identification. In addition, two viral proteins, the large tumor antigen (LT) and the major structural protein (VP1), were detected by immunohistochemistry (IHC). Human JCPyV and BKPyV DNA was detected in 14 out of 16 tissue samples (87.5%), whereby nine cases were infected with JCPyV and five cases were infected with BKPyV. Both archetypal and rearranged genotypes of JCPyV and BKPyV were detected in the tissues. LT was detected in 11 tissue samples (68.75%). However, VP1 was not detected in any of the tissue samples. The presence of human JCPyV and BKPyV DNA and protein in DLBCL tissues of gastrointestinal tract were first reported in this study. The current results provide evidence of a possible association between human JCPyV and BKPyV infection and DLBCL.

p53 levels in human mammary epithelial cells expressing wild-type and mutant human papillomavirus type 16 (HPV-16) E6 proteins

Human fibroblast cells must overcome both the M1 and the M2 stages of cellular senescence to immortalize, at which point cells almost always express telomerase activity. The human papillomavirus (HPV) oncoproteins, HPV-16 E6 and E7, can block the progression to senescence in fibroblasts by associations with p53 and pRb, respectively. Human mammary epithelial (HME) cells require only HPV-16 E6 to bypass M1, suggesting that pRb may not have a direct role in HME cells senescence. In the present report, we show that only wild-type HPV-16 E6 allows complete degradation of p53, immortalization and reactivation of telomerase activity in HME cells. These results suggest that the ability of HPV-16 wild-type and mutant E6 proteins to degrade p53 in intact HME cells and keratinocytes does not completely correlate with their ability to degrade p53 in a cell-free system. This discrepancy between in vitro and in vivo p53 degradation may be biologically significant and may provide insight into the susceptibility of certain human cells and tissues for reactivation of telomerase and immortalization.

Telomerase activity in human intestine

In human somatic cells without the activity of telomerase, the ends of chromosomes consisting of the telomeric repeats TTAGGG progressively erode with each cell division. In germline and immortal cells telomerase activity maintains telomere length and thus compensates for the 'end-replication problem'. Progressive telomere shortening and reactivation of telomerase activity have been considered to be one of the key mechanisms in cellular senescence and immortalization. It has been shown that while most somatic cells do not have detectable telomerase activity, almost all cancers do have telomerase activity. Thus, detection of telomerase activity may have utility in the early diagnosis of cancer and may be a new target for therapeutic intervention. However, there is recent evidence that some cells of renewal tissues, such as hematopoietic cells and basal cells of the epidermis, have detectable telomerase activity. In the present study, we report detectable telomerase activity in normal human intestinal mucosa. This activity is localized to the lower third of each crypt and may be derived from intestinal stem cells. Since intestinal telomeric repeats are shorter in adults when compared to children, the telomerase activity in the intestine is insufficient to maintain telomere length but may be sufficient to provide extended proliferative capacity for such renewal tissues.

Loss of telomeric DNA during aging may predispose cells to cancer (review)

In normal human somatic cells, gradual shortening of telomeres may activate the complex cascade of molecular events known as cellular senescence. Experimental evidence from our laboratory suggests that cellular mortality is regulated by two separate mechanisms that we have termed mortality stage 1 (M1) and mortality stage 2 (M2). In mammary epithelial cells, the M1 mechanism involves de-regulation of p53 whereas in fibroblasts both the retinoblastoma (Rb) and p53 gene products are implicated. Cells that overcome the function of these antiproliferative proteins (M1 controls) continue to divide until a second entirely independent mechanism, M2 is induced. As somatic cells age they gradually lose telomeric sequences at the termini of their chromosomes, a process that continues during the extended lifespan period between M1 and M2. Immortal and cancer cells, as well as cells that maintain telomere length (e.g. germ cells), express telomerase, a ribonucleoprotein which maintains (stabilizes) telomere length by synthesizing TTAGGG repeats. Because normal human somatic cells and cells prior to M2 do not express telomerase, we propose that the M2 mechanism involves either the direct or indirect induction of telomerase activity. In order for cells to overcome senescence and become immortal, they must first escape the checkpoints that limit the proliferative capacity of normal cells, the MI and M2 controls (a very rare event). However, the probability of immortalization and that of tumorigenesis increases with age and we propose telomere shortening and reactivation of telomerase are important components in these processes. Once immortal, cells can then follow many pathways that result in the acquisition and progression of cancer.

Telomerase inhibitors--oligonucleotide phosphoramidates as potential therapeutic agents

We have designed, synthesized, and evaluated using physical, chemical and biochemical assays various oligonucleotide N3'-->P5' phosphoramidates, as potential telomerase inhibitors. Among the prepared compounds were 2'-deoxy, 2'-hydroxy, 2'-methoxy, 2'-ribo-fluoro, and 2'-arabino-fluoro oligonucleotide phosphoramidates, as well as novel N3'-->P5' thio-phosphoramidates. The compounds demonstrated sequence specific and dose dependent activity with IC50 values in the sub-nM to pM concentration range.

Effects of oral supplementation with evening primrose oil for six weeks on plasma essential fatty acids and uremic skin symptoms in hemodialysis patients

Abnormalities in plasma composition of essential fatty acids (EFAs) may be associated with the etiology of pruritus and other skin problems in patients undergoing hemodialysis. To study whether an oral supplementation with omega-6 (n-6) EFAs would restore deranged plasma EFAs and ameliorate skin symptoms, 9 and 7 dialysis patients were randomly assigned to receive either gamma-linolenic acid (GLA)-rich evening primrose oil (EPO) or linoleic acid (LA) (2 g/day each) for 6 weeks. Plasma concentrations of EFA were analyzed by gas chromatography and uremic skin symptoms were assessed for dryness, pruritus and erythema by questionnaire and visual inspection in a double-blind manner. The patients given EPO exhibited a significant (p < 0.05) increase in plasma dihomo-gamma-linolenic acid (a precursor of anti-inflammatory prostaglandin E1) with no concomitant change in plasma arachidonic acid (a precursor of pro-inflammatory prostaglandin E2 and leukotriene B4). In contrast, those given LA exhibited a significant (p < 0.05) increase in LA but not in any other n-6 EFAs, whereas they exhibited a significant (p < 0.05) decrease in plasma docosahexaenoic acid. The patients given EPO showed a significant (p < 0.05) improvement in the skin scores for the three different uremic skin symptoms over the baseline values and a trend toward a greater improvement (0.05 < p < 0.1) in pruritus scores than those given LA. Results indicate that GLA-rich EPO would be a more favorable supplemental source than LA in terms of shifting eicosanoid metabolism toward a less inflammation status through modifying plasma concentrations of their precursor n-6 EFAs. Further studies are required to confirm the efficacy and safety of EPO therapy for the treatment of uremic pruritus.

Omega-3 polyunsaturated fatty acid levels in the diet and in red blood cell membranes of depressed patients

BACKGROUND

There is a hypothesis that lack of n-3 polyunsaturated fatty acids (PUFAs) is of aetiological importance in depression. Docosahexaenoic acid, a member of the n-3 PUFA family, is a crucial component of synaptic cell membranes. The aim of this study was to measure RBC membrane fatty acids in a group of depressed patients relative to a well matched healthy control group.

METHOD

Red blood cell (RBC) membrane levels, and dietary PUFA intake were measured in 10 depressed patients and 14 matched healthy control subjects.

RESULTS

There was a significant depletion of RBC membrane n-3 PUFAs in the depressed subjects which was not due to reduced calorie intake. Severity of depression correlated negatively with RBC membrane levels and with dietary intake of n-3 PUFAs.

CONCLUSION

Lower RBC membrane n-3 PUFAs are associated with the severity of depression.

LIMITATIONS

Although patient numbers were small, confounding factors were well controlled for and the results were highly significant. Results of the dietary data would tend to be weakened due to the limitations associated with dietary assessment.

CLINICAL RELEVANCE

The findings raise the possibility that depressive symptoms may be alleviated by n-3 PUFA supplementation.

Depletion of omega-3 fatty acid levels in red blood cell membranes of depressive patients

BACKGROUND

It has been hypothesized that depletion of cell membrane n3 polyunsaturated fatty acids (PUFA), particularly docosahexanoic acid (DHA), may be of etiological importance in depression.

METHODS

We measured the fatty acid composition of phospholipid in cell membranes from red blood cells (RBC) of 15 depressive patients and 15 healthy control subjects.

RESULTS

Depressive patients showed significant depletions of total n3 PUFA and particularly DHA. Incubation of RBC from control subjects with hydrogen peroxide abolished all significant differences between patients and controls.

CONCLUSIONS

These findings suggest that RBC membranes in depressive patients show evidence of oxidative damage. Possible interpretations, and implications for the etiology and treatment of depression, are discussed.

Analysis of the FHIT gene and FRA3B region in sporadic breast cancer, preneoplastic lesions, and familial breast cancer probands

The FHIT gene, which spans the FRA3B fragile site at chromosome 3p14.2, is a candidate tumor suppressor gene in breast and other cancers. We investigated FHIT and FRA3B for loss of heterozygosity (LOH); homozygous deletions; abnormal transcripts; and acquired/germ-line point mutations in breast cancer cell lines (n = 32), breast epithelial and stromal cell cultures (n = 18), microdissected invasive (n = 16) and ductal in situ carcinomas (n = 6), and their accompanying normal and abnormal epithelial foci (n = 14). LOH at 3p14.2, especially at FHIT intragenic marker D3S1300, was found in 6 of 16 microdissected invasive tumors and 3 of 6 ductal in situ carcinomas. In accompanying preneoplastic foci, LOH occurred in two of eight intraductal hyperplasias but not in histologically normal ductal epithelium (n = 6). Three of 32 (9%) breast cancer cell lines demonstrated homozygous deletions of FHIT exon 4 (two cases) and exon 5 (one case), which correlated with exon 4-deleted transcripts and loss of the cDNA transcript containing the coding exons 5-9, respectively. Normal mammary cultures and 31 of 32 tumor cell lines (97%) expressed wild-type coding transcripts as well as a minor exon 8-deleted message. Single-strand conformation polymorphism analysis of the coding exons in the 32 tumor and 18 normal breast cell lines and their sequencing revealed four silent polymorphisms and a germ-line histidine triad point mutation (651 G-->T) in a tumor arising in a 70-year-old woman. This mutation was also present in one of her two thus far unaffected daughters. Analysis of additional DNAs from 280 probands of high-risk breast cancer families for other FHIT exon 8 mutations detected an intronic point mutation 13 bases upstream of exon 8. Thus, we have demonstrated relatively early abnormalities of the FHIT/FRA3B region in breast cancer and discovered two rare FHIT germ-line mutations. The expression of a transcript containing the coding exons in nearly all cell lines, including those with germ-line mutations, suggests the possibility that another gene in the FRA3B region may be involved in the pathogenesis of breast cancer.

Telomerase reactivation in leukemia cells

We utilized fluorescent-labeled primers and modified the telomeric repeal amplification protocol (TRAP) to assess telomerase activity during the process of in vitro establishment in four different leukemia cell lines. We demonstrate that three of four leukemia cell lines had elevated telomerase activity, shortened telomeres, and the appearance of either dicentric chromosomes or acentric fragments. By contrast, one leukemia cell line (HAL-01) had high levels of telomerase activity, stable telomeres, but no obvious additional cytogenetic rearrangements. These experiments indicate that there may be several pathways involving telomerase activity in the establishment of leukemia cell lines.

The first intron of human h-ras is regulated by p53 - mediation of specific activation by a p53-binding element

We conducted transient reporter gene expression assays to show that the wild-type but not the mutant-type p53 protein positively regulates the expression of the human H-ras gene. This activation of expression is mediated through a specific p53-binding DNA element located in the first intron of the H-ras gene. This element is similar to a previously identified p53-binding element. Without this element, wild-type p53 represses the H-ras promoter, as do several p53 mutants. The repression function is lost when the N-terminal 81 amino acids of the p53 protein are deleted, suggesting that the N-terminus is required for repression. Therefore, p53 seems to regulate the H-ras through both positive and negative mechanisms.

Trauma contagion in partners of survivors of childhood sexual abuse

Partners of survivors of childhood sexual abuse may develop a "trauma contagion" marked by high levels of stress, doubts about to key personal values and assumptions about the world, and a tendency to be drawn into unconscious reenactments with the survivor of the abusive relationship. Various treatment interventions are discussed, especially conjoint work with the survivor.

Nitric oxide accounts for dose-dependent estrogen-mediated coronary relaxation after acute estrogen withdrawal

BACKGROUND

Estrogen replacement therapy reduces the risk of coronary heart disease in postmenopausal women, and estrogen treatment modulates endothelium-dependent vasodilation in ovariectomized, atherosclerotic monkeys. Estradiol-17 beta also induces relaxation in isolated rabbit coronary arteries as well as cerebral basilar arteries. The estrogen concentrations required to induce such relaxation are in the pharmacological range (10(-6) to 10(-5) mol/L).

METHODS AND RESULTS

The present study was designed to test whether the sensitivity and specificity of the relaxing response of coronary vascular smooth muscle to exogenous estradiol-17 beta is dependent on the sex hormone status of the animal. In coronary artery rings contracted with PGF2 alpha (3 x 10(-5) mol/L), estradiol-17 beta caused significant relaxation at a physiological estrogen concentration (10(-9) mol/L), in coronary artery rings from oophorectomized, estrogen-treated and acutely estrogen-withdrawn rabbits only. Relaxation induced by estradiol-17 beta at lower concentrations (10(-9) to 10(-6) mol/L) in these rings was 20 +/- 6%, 42 +/- 8%, 54 +/- 9%, and 75 +/- 8%, respectively, compared with 4 +/- 2%, 12 +/- 5%, 16 +/- 7%, and 25 +/- 12% and 5 +/- 2%, 12 +/- 5%, 18 +/- 8%, and 23 +/- 10% in rings from estrogen-maintained and oophorectomized rabbits, respectively (P < .01). The relaxation in coronary artery rings from estrogen-treated and acutely estrogen-withdrawn rabbits was endothelium and nitric oxide dependent since it was abolished by endothelium removal and the nitric oxide synthase inhibitor N omega-nitro-L-arginine.

CONCLUSIONS

This study demonstrates that estrogen-induced, endothelium-dependent relaxation of coronary arteries may, in some species, depend on the sex hormone status of the animal. These findings may help to better understand the effects of ovarian steroids in the coronary circulation of females.

Estrogen withdrawal selectively increases serotonin reactivity in rabbit basilar artery

Clinical observations and laboratory investigations suggest that gender and menstrual status modulate cerebrovascular reactivity. We prepared 7 groups of rabbits (I) males (II) oophorectomized untreated females, (III) testosterone treated oophorectomized females, (IV) superovulated females, (V) superovulated estrogen withdrawn females, (VI) estrogen treated oophorectomized females, and (VII) estrogen withdrawn females to mimic phases of the estrous cycle and compare cerebral basilar artery reactivity to serotonin (5-HT) and norepinephrine (NE) in vitro. Basilar artery sensitivity to 5-HT vasoconstriction was increased in oophorectomized, acutely estrogen withdrawn females (Group VII) when compared to estrogen maintained and the other groups (p < 0.0001). There was a significant reduction in 5-HT sensitivity in superovulated females (Group IV) (p < 0.001). The change in 5-HT sensitivity is selective and was not observed for NE. Nitroarginine treatment and mechanical denudement resulted in higher Tmax and lower ED50 for both NE and 5-HT regardless of hormonal manipulation. We conclude that estrogen withdrawal increases 5-HT vasoreactivity by an endothelium independent mechanism.

Estrogen and progesterone withdrawal increases cerebral vasoreactivity to serotonin in rabbit basilar artery

An in vitro animal model which examines the effects of sex hormone variations during the menstrual cycle on basilar artery reactivity is presented. Three groups of rabbits were utilized: a chronically depleted control group which received no further hormonal treatment after bilateral surgical oophorectomy (O), simulating menopause, and two groups of intact females, one of which was treated to mimic the estrogen and progesterone surge during the luteal phase (H) and the third group which was acutely estrogen and progesterone depleted after the luteal surges to simulate the immediate premenstrual state (W). We show that both acute and chronic estrogen and progesterone withdrawal significantly increase serotonin sensitivity (ED50) in basilar artery rings. There was no difference between groups for maximum contraction (Tmax) to serotonin, nor optimal resting tension. Furthermore, there was no difference in vasoreactivity and contractility to norepinephrine between groups. In order to distinguish between the effects of chronic and acute treatment we examined acute estrogen and progesterone superfusion in basilar artery rings from intact non-treated female rabbits. Acute superfusion of pre-contracted and non-pre-contracted artery segments resulted in significant dilatation only when supraphysiologic concentrations of estrogen and progesterone were used. We conclude that both acute and chronic female sex hormone withdrawal selectively increases cerebral vasoreactivity to serotonin.

The effect of maternal supplementation with linoleic and gamma-linolenic acids on the fat composition and content of human milk: a placebo-controlled trial

Total fat content and therefore total energy content and the content of essential fatty acids (EFAs) in milk are known to decline with prolonged breast feeding. In a placebo-controlled study a variety of evening primrose oil (Efamol) rich in linoleic and gamma-linolenic acids, or a matching placebo were given to 39 women for a period of 8 months starting between the 2nd and 6th months of lactation. Total fat and EFA contents of the milk declined in the placebo group but rose in the primrose oil supplemented group. A surprisingly high proportion of the supplemented dietary fatty acids could be accounted for by appearance in the milk. The milk composition can be readily manipulated by changing the fatty acid composition of the maternal diet.

Effects of linoleic and gamma-linolenic acids (efamol evening primrose oil) on fatty acid-binding proteins of rat liver

We have studied the effects of Efamol evening primrose oil (EPO) on fatty acid-binding proteins (L-FABP) of rat liver. EPO contains 72% cis-linoleic acid and 9% cis-gamma linolenic acid. EPO has been clinically used for treatment of a number of diseases in humans and animals. EPO is also known to lower cholesterol level in humans and animals. Feeding of an EPO supplemented diet to rats (n = 9) for 2 months decreases the oleate binding capacity of purified L-FABP of rat liver whereas the palmitate binding activity was increased by 38%. However, EPO feeding did not alter the L-FABP concentrations significantly as measured by using the fluorescence fatty acid probe, dansylamino undecanoic acid. Endogenous fatty acid analysis of L-FABPs revealed significant qualitative and quantitative changes in fatty acid pattern after EPO feeding. EPO feeding decreased the endogenous palmitate level by 53% and oleate level by 64% in L-FABPs and also EPO feeding decreased the total endogenous fatty acid content from 62 nanomole per mg of protein to 42 nanomole per mg of L-FABP (n = 3).

Solid base working cast

A technique is presented to facilitate the fabrication of single or multiple restoration die working casts. The technique allows a full remount potential for use especially in multiple centric relation record verification techniques. A die removal technique that will not damage the brass dowel pin is suggested.

Anoxic cell swelling dissociated from excess permeability by poorly penetrating solutes

Increased plasma membrane permeability, cell swelling, and cell death are consequences of metabolic energy deprivation. Rabbit retinas were incubated in an oxygenated artificial cerebrospinal fluid containing glucose. The incubating medium was modified by causing anoxia and glucose deprivation with one of the following treatments: addition of 97 mM mannitol, equimolar substitution of choline+ for Na+, or substitution of isethionate- for Cl-. Some retinas were resupplied with oxygen and glucose to determine the consequences of solute manipulation. Water compartments and membrane permeability were assayed using [3H]inulin and [14C]mannitol. Abnormal nuclei were counted on blind-coded slides. Both treatments prevented doubling of inulin-free water of untreated retinas after 70 min of deprivation. Neither treatment preserved morphology or prevented massive swelling after restoration of oxygen and glucose and gradual removal of the treatment. Mannitol leaked into deprived cells only, even when swelling was prevented. We conclude that prophylaxis of cell swelling during metabolic energy deprivation prevents neither cell leakiness nor cell death.

Combination prosthesis for optimum esthetic appearance

A method of treatment that combines the advantages of both a removable partial denture and a fixed partial denture is described. The indications, contraindications, advantages, and special considerations are discussed. The procedures necessary for treatment of patients are described. Our observations indicate that this is an acceptable mode of treatment for those patients in need of this type of prosthesis.

Retina subjected to components of ischemia in vitro. Selective vulnerability and minimum lethal exposure of neurons and glia to oxygen and/or glucose deprivation and to loss of exchange with incubating medium

Rabbit retinas were incubated at 37 C in media lacking oxygen, glucose, or both, or sealed in a small compartment without medium to convert them to a "closed system." They were then returned to control medium before being fixed for microscopy. Other retinas were incubated only in control medium and then fixed. Conversion of the retina to a closed system caused irreversible damage to all cell types within 40 minutes. Combined deprivation of oxygen and glucose also irreversibly damaged the neuronal cells within 40 minutes, but Mueller cells,the principal glial cells of the retina, were not irreversibly altered by 90 minutes of the deprivation. Deprivation of oxygen alone caused irreversible damage to receptor cells in 80 minutes, but the cells of the inner nuclear layer, ganglion cells, and Mueller cells retained normal structure for at least 180 minutes. Deprivation of glucose alone damaged receptor cells in 160 minutes and the other neuronal cells in 180 minutes, but did not irreversibly damage Mueller cells by 200 minutes.

Cell volume and permeability of oxygen-and glucose-deprived retina in vitro

Rabbit retina was deprived of O(2) and glucose in vitro for up to four hours at 37 C. Intracellular volume was measured, using inulin as an extracellular marker. After a 30-minute latency, cells swelled rapidly to more than twice normal volume while extracellular volume was unchanged. Intracellular accumulation of water was not reversed by resupply of oxygen and glucose. Permeability to small molecules was assessed with mannitol. The ratio of mannitol space to inulin space averaged 1.0 in controls. This ratio remained 1.0 up to 30 minutes of deprivation, but increased to 1.2 by 60 minutes. Permeability to large molecules was assessed from the rate of loss of isotopically labeled cell protein into the medium. There was no difference between control and deprived retinas up to three hours.

Economy of effort in electron microscope morphometry

Statistical techniques known as the analysis of variance make it possible for the electron microscopist to plan work in such a way as to get quantitative data with the greatest possible economy of effort. This paper explains how to decide how many measurements to make per micrograph, how many micrographs per tissue block, how many blocks per experimentally treated organ, and how many organs per experimental treatment group.

Reconstruction of mammalian cells from nuclear and cytoplasmic components separated by treatment with cytochalasin B

Mouse L929 cells were separated into enucleated cytoplasmic components (cytoplasts) and nucleated subcellular fractions (karyoplasts) in the presence of cytochalasin B. Karyoplasts from cells containing tritiated nuclei were fused, using inactivated Sendai virus, to cytoplasts from cells containing large (1.0-mum diameter) latex spheres in the cytoplasm. Mononucleated cells containing radioactive nuclei and large latex spheres in the cytoplasm were observed among the products of the fusion reaction. Some of these cells were in mitotic configurations. The results indicate that cells capable of undergoing mitosis can be reconstructed from the products of cellular enucleation in the presence of cytochalasin B.

Electron microscopy of cat spinal cord subject to circulatory arrest and deep local hypothermia (15 C)

Circulatory arrest to the lumbar spinal cord of adult cat was produced by occlusion of the descending aorta and concurrent arterial hypotension. Local hypothermia of the cord was induced by paraffin oil at 5 C, which was circulated over the exposed surface of the cord, using the laminectomy wound as a trough. Intramedullary temperature was 15 C at a depth of 5 mm. In 10 control animals oil at 37 or 5 C was circulated over the exposed cords (normal-normothermic and normal-hypothermic controls with 1 and 2 hours hypothermia). Three animals had circulatory arrest and recirculation in normothermia (ischemic-normothermic) and 3 in hypothermia (ischemic-simultaneous hypothermia). Three had circulatory arrest and 15 minutes of recirculation in normothermia followed by 1 hour of hypothermia (ischemic-delayed hypothermia). The medial and lateral portions of the anterior gray horns of the last lumbar spinal segment were studied in the light and electron microscopes. Ischemic-normothermic tissue showed 20% shrinkage in mean areas of neuronal perikarya and massive "watery" swelling of astrocytic cell bodies and processes. Within neuronal perikarya and dendrites, cytoplasm increased in electron density, ribosomes dispersed, Golgi apparatus swelled and mitochondria swelled with loss of matrix density and disruption of cristae. Axons and axon terminals did not increase in size, but mitochondria within these structures doubled in size without loss of matrix density or change in pattern of cristae. Synaptic vesicles were no longer uniform in size, and they were clumped away from the synaptic cleft and diminished in number. Lysosomes were unchanged in appearance and size. Mitochondria of astrocytes underwent approximately fourfold enlargement without loss of matrix density or pattern of cristae. Bundles of astrocytic microfilaments were fragmented, spread apart and diminished in quantity. Oligodendroglia and endothelial cells were unchanged. Normal-hypothermic animals were similar to normal-normothermic except for clefts in rough endoplasmic reticulum of neurons and dendrites. These clefts were formed by a separation of the cisternal membrane from the adjacent row of ribosomal rosettes. Ischemic-simultaneous hypothermia animals had findings identical to normal-hypothermic animals. Ischemic-delayed hypothermia animals were similar to ischemic-normothermic animals except for less swelling of astrocytic processes, greater swelling of astrocytic mitochondria and less alteration of microfilaments. The findings show that ischemia in normothermia brings about alterations in virtually every organelle of the neurronal perikaryon except the lysosome. Simultaneous hypothermia in ischemia prevents the protean alterations of ischemia, whereas hypothermia delayed until after the ischemic episode only slightly modifies the cellular lesions found in ischemic-normothermic animals.

Morphometry of an ischemic lesion of cat spinal cord

Profiles in random electron micrographs of anterior gray matter of normal and ischemic cat spinal cord were measured with a planimetric computer. Analysis of 5600 area measurements revealed the following differences. Mitochondria of neuron cell bodies, axons, axon terminals and astrocytic processes were two to three times larger after ischemia. However, only 15% of mitochondria of axons and axon terminals and 5% of astrocytic processes lost their matrix density and pattern of cristae, compared to 49% of mitochondria of neuron cell bodies. Ischemia caused no significant changes in mean sizes of axons or axon terminals. Lysosomes in neurons were unchanged. The mean size of astrocytic processes increased more than threefold.