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Closure of an abdominal stoma, a common elective operation, is associated with frequent complications; one of the commonest and impactful is incisional hernia formation. We aimed to investigate whether biological mesh (collagen tissue matrix) can safely reduce the incidence of incisional hernias at the stoma closure site.

AbstractBackground:The growth of Escherichia coliO157:H7 in contaminated dairy and other refrigerated food products due to temperature fluctuation poses a major food safety threat. Effective control or inhibition of E. coliO157:H7 growth depends on our understanding of mechanisms that regulate its growth at low temperature. We hypothesized that polynucleotide phosphorylase (PNPase) plays a critical role in E. coliO157:H7 low-temperature growth.Methods:To test this hypothesis, the pnpdeletion mutant of E. coliO157:H7 was generated using the λ Red recombinase system, and the growth and survival of wild-type and pnpdeletion mutant strains were compared at low temperatures.Results:The growth of pnpdeletion mutant strains in Luria Broth (LB) and agar plate at 37°C was similar to their corresponding wild-type strains, while the deletion of pnpimpaired E. coliO157:H7 growth in LB at 10°C and 22°C; growth impairment could be partially recovered in the mutant strains by ectopic expression of the pnpcomplementation plasmid, demonstrating that growth impairment was PNPase-specific. During 14 days of 10°C storage in both LB and milk, wild type strain EDL933 grew and reached >8 log10colony-forming units per milliliter after 4 days of 10°C storage, while EDL933Δpnpgradually died off with effects more pronounced in milk, which were again mitigated by pnpoverexpression. In addition, pnpdeletion impaired the motility of E. coliO157:H7 but did not affect its susceptibility to H2O2.Conclusion:PNPase is required for the growth of E. coliO157:H7 at low temperature; PNPase thus provides a molecular target to control the growth of E. coliO157:H7, which may have important practical applications in dairy and other food industry.

Early gestation is critical for placentomal growth, differentiation, and vascularization, as well as fetal organogenesis. The fetal origins of adult disease hypothesis proposes that alterations in fetal nutrition and endocrine status result in developmental adaptations that permanently change structure, physiology, and metabolism, thereby predisposing individuals to cardiovascular, metabolic, and endocrine disease in adult life. Multiparous ewes were fed to 50% (nutrient restricted) or 100% (control fed) of total digestible nutrients from Days 28 to 78 of gestation. All ewes were weighed weekly and diets adjusted for individual weight loss or gain. Ewes were killed on Day 78 of gestation and gravid uteri recovered. Fetal body and organ weights were determined, and numbers, morphologies, diameters, and weights of all placentomes were obtained. From Day 28 to Day 78, restricted ewes lost 7.4% of body weight, while control ewes gained 7.5%. Maternal and fetal blood glucose concentrations were reduced in restricted versus control pregnancies. Fetuses were markedly smaller in the restricted group than in the control group. Further, restricted fetuses exhibited greater right- and left-ventricular and liver weights per unit fetal weight than control fetuses. No treatment differences were observed in any gross placentomal measurement. However, caruncular vascularity was enhanced in conceptuses from nutrient-restricted ewes but only in twin pregnancies. While these alterations in fetal/placental development may be beneficial to early fetal survival in the face of a nutrient restriction, their effects later in gestation as well as in postnatal life need further investigation.

This study reports the concentration of collagen and its hydroxypyridinoline crosslinks, collagen fibril organization in the dorsal aortas, and systolic blood pressure during the progression of atherosclerosis in Japanese quail selected for cholesterol-induced atherosclerosis. The quail were placed on either a control or 0.5% cholesterol-added diet at approximately 16 weeks of age. The concentration of total collagen did not change in the control arteries during the course of the study, whereas at 5 and 10 weeks of cholesterol feeding, collagen levels decreased in the cholesterol-fed birds. Hydroxypyridinoline concentration increased during the duration of the study in the cholesterol-fed birds and by 15 and 20 weeks of cholesterol feeding, levels were significantly increased over those observed in the control arteries. Transmission electron microscopy showed changes in the organization of collagen fibrils. Increased systolic blood pressure was noted beginning at 10 weeks of cholesterol feeding, which is suggestive of other systemic changes induced by hypercholesterolemia. These results demonstrated remodeling of the collagen component of the dorsal aorta extracellular matrix during the progression of atherosclerosis and are suggestive of other systemic cardiovascular system changes.

Whether or not exercise training of sufficient intensity and duration to produce left ventricle (LV) hypertrophy also regulates deposition of interstitial collagen and cross-linking at the pretranslational level is unknown. Therefore, the effects of exercise training on gene expression for the two principal fibrillar collagens in LV, types I and III, were assessed in young adult (5 mo), middle-aged (15 mo), and old (26 mo) rats. We also evaluated the potential interaction of changes in mRNA for these procollagens with alterations in LV extracellular matrix characteristics by simultaneously measuring collagen concentration (hydroxyproline) and extent of mature collagen cross-linking (hydroxylysylpyridinoline, HP). Ten weeks of treadmill running resulted in LV hypertrophy and an increased maximal oxygen uptake in all three age groups of trained rats compared with sedentary controls. Percent collagen in rat LV almost doubled (P< 0.0001) from 5 to 26 mo of age, an increase unaffected by exercise training. With aging, a significant decline in expression of mRNAs for both collagen type I (P< 0.005) and type III (P< 0.001) was observed in LV free wall (LVF) but not septum (LVS). Training prevented this decline in LVF mRNAs for the two principal fibrillar collagens in middle-aged rats whereas it attenuated the decline in senescent animals. HP concentration increased significantly with aging in both LVF (P< 0.005) and LVS (P< 0.01). Training modulated this effect, but again only in LVF, so that HP was significantly lower (P< 0.05) in this region of the LV in old trained rats compared with sedentary counterparts. We conclude that exercise training modulates the effects of aging on collagen gene mRNAs and HP cross-linking regionally within the LV.

The purpose of this study was to evaluate the effect of endurance exercise training on both locomotor skeletal muscle collagen characteristics and passive stiffness properties in the young adult and old rat. Young (3-mo-old) and senescent (23-mo-old) male Fischer 344 rats were randomly assigned to either a control or exercise training group [young control (YC), old control (OC), young trained (YT), old trained (OT)]. Exercise training consisted of treadmill running at ∼70% of maximal oxygen consumption (45 min/day, 5 days/wk, for 10 wk). Passive stiffness (stress/strain) of the soleus (Sol) muscle from all four groups was subsequently measured in vitro at 26°C. Stiffness was significantly greater for Sol muscles in OC rats compared with YC rats, but in OT rats exercise training resulted in muscles with stiffness characteristics not different from those in YC rats. Sol muscle collagen concentration and the level of the nonreducible collagen cross-link hydroxylysylpyridinoline (HP) significantly increased from young adulthood to senescence. Although training had no effect on Sol muscle collagen concentration in either age group, it resulted in a significant reduction in the level of Sol muscle HP in OT rats. In contrast, exercise had no effect on HP in the YT animals. These findings indicate that 10 wk of endurance exercise significantly alter the passive viscoelastic properties of Sol muscle in old but not in young adult rats. The coincidental reduction in the principal collagen cross-link HP also observed in response to training in OT muscle highlights the potential role of collagen in influencing passive muscle viscoelastic properties.

Birth regulation is a tired and worn-out conversation, so I will not approach the matter in that way. I think it much more exciting, and it raises all the same problems, to approach the issues of reproductive services through reproductive technologies that are now available. Since this is based on my recent experience with the American Fertility Society, now the American Society of Reproductive Medicine, I will take this tack. This presentation is a vehicle for getting some questions on the table; hopefully, there will be enlightenment in the discussion and debates that follow.

My discussion is presented in three steps: The present position of the Catholic Church; why it is a relatively recent tradition; and the roots of the tradition.

Abstract:The so-called "New Objectivity" in the arts and culture of the Weimar Republic was characterized by an erosion of the boundary between the "high culture" associated with the bourgeois public sphere and new forms of mass culture directed at other classes in the emerging modern consumer society. Related to this erosion of boundaries were anxieties about the destabilization of traditional models of (national, ethnic, class, gender, sexual) identity. Change seemed especially threatening in its effect on traditional ("natural") gender roles, as can readily be demonstrated in G.W. Pabst's film Geheimnisse einer Seele(1926). Similar anxieties about gender are also crucial to subsequent developments in German culture and society. (RWM)

Ovine longissimus dorsi and biceps femoris muscles were analyzed for proteoglycan content, collagen and lysine aldehyde-derived collagen crosslinking concentrations at 2-4 days, six-month-old, and six-year-old stages of development. Tissue extracted proteoglycan molecular sieve distribution on a Sephacryl S-200HR column revealed two proteoglycan populations with estimated relative molecular weight ranges of 200,000 to 250,000 daltons and 23,000 to 70,000 daltons. The molecular sieve distribution was similar between the two muscles within a developmental age, but changed as a function of developmental age. Primary culture from both the longissimus dorsi and biceps femoris muscle liberated proteoglycans into the culture medium. In contrast to the tissue extracted proteoglycans, at the six-year-old stage of development, culture medium liberated proteoglycan Sephacryl S-200HR molecular sieve distribution differed between the two muscles. In both the tissue extracted and medium liberated proteoglycans at all developmental stages, nitrous acid deamination demonstrated the presence of heparan sulfate. Immunoblot analysis of the tissue extracted proteoglycans indicated the presence of decorin at each developmental stage. Longissimus dorsi and biceps femoris collagen concentrations (5.13 ± 0.9 vs. 5.53 ± 1.5%, respectively) and crosslink concentrations (0.07 ± 0.01 moles HP/mole collagen) were initially similar between the two muscles; however, by six-months the muscles differed in both collagen concentration (1.72 ± 0.5 and 2.53 ± 0.7%, respectively) and crosslinking (0.24 ± 0.02 and 0.27 ± 0.03 moles HP/mole collagen, respectively). At six years of age, both the longissimus dorsi and biceps femoris exhibited slightly elevated collagen concentrations (2.49 and 3.05%, respectively) while crosslinking values were decreased relative to values at six-months of age (0.11 ± 0.01 and 0.18 ± 0.01 moles HP/mole of collagen, respectively). The results from this study indicate that skeletal muscle proteoglycans and collagen show developmental changes, which suggests that they are subject to developmental regulation.

A few recent investigations have indicated that it is possible for mammalian ovulation to progress to completion in the absence of a preovulatory rise in ovarian prostanoid production and that the antiovulatory mode of action of antiinflammatory agents (e.g., indomethacin) could be independent of their ability to inhibit the cyclooxygenase pathway of arachidonate metabolism. Mature ewes were treated during the preovulatory period with a systemic dosage of indomethacin that either consistently did (500 mg) or did not (100 mg) prevent follicular rupture. With both dosages, the rise in follicular production of prostaglandin F2αfollowing the surge in secretion of LH was negated. Indomethacin did not affect periovulatory patterns of change in follicular tissue concentrations of estradiol-17β, testosterone, or progesterone. The 500-mg dose of indomethacin inhibited collagen breakdown within the follicular wall as deduced from measurement of tissue levels of hydroxyproline. In vitro secretion of a follicular leukotactic agent and accumulation of extravascular white blood cells within the theca interna of periovulatory follicles were also suppressed by the ovulation-inhibiting dose of indomethacin. It appears that the blockage of ovulation induced by indomethacin in the sheep is largely unrelated to its capacity to suppress follicular prostaglandin biosynthesis; rather, it is more directly associated with effects on follicular collagenolysis and leukocyte chemoattraction.

Studies were performed to determine if periovulatory ovine follicles secrete chemoattractants for leukocytes, and if so, to begin to elucidate the chemical nature of such factors. Tissues were obtained at 0, 12, 24, and 36 h Ater initiation of the preovulatory surge of luteinizing hormone and placed in short-term incubation (ovulation occurs at approximately 24 h). Follicular-conditioned medium was tested for its ability to attract leukocytes by utilizing a linear under-agarose assay: chemotaxis was quantified as a function of the leading front of migration of cells. Neutrophils and eosinophils were attracted toward media conditioned with tissues of 24 and 36 h. Monocytes responded toward medium of tissues collected at 36 h. There was no evidence for chemoattraction of basophils or lymphocytes. Chemoattractant activity for granulocytes and monocytes was of low molecular weight origin (<3000) and water-soluble. High performance liquid chromatographic separation of this sample produced a distinct peak with recoverable activity. The isolated fraction was rich in glycine. Eosinophils also migrated toward an additional low molecular weight attractant that was extracted into ethyl acetate. Leukocytes attracted into periovulatory follicles might produce substances (eg., proteolytic enzymes and angiogenic factors) that play a role in the mechanisms of ovulation and luteinization.

Male pathological gamblers entering a comprehensive treatment program were followed-up for twelve months after treatment completion. Twelve month follow-up was obtained for 45 of the 66 patients entering treatment. Total abstinence was reported by 55% (n=25) of the patients located for twelve month follow-up. A relationship was found between abstinence at six month follow-up and selected subscales of the Wechsler Adult Intelligence Scale, performance scale. The implications of these findings for sub-typing gamblers are discussed.

Substance abusers with borderline personality disorder (n = 34) were compared with substance abusers who were not borderline (n = 89) on measures of impulsivity, coping skills, hostility, negative affect, and triggers for craving or relapse. Borderline substance abusers abused more substances over the course of their lifetime and scored significantly higher on measures of impulsivity. Borderline substance abusers utilized escape/avoidance coping mechanisms more often, and used problem solving and positive reappraisal less often than nonborderline substance abusers. Borderlines had cravings and relapses triggered more often by negative emotional states, tension, social rejection, and negative physical states. The findings support the utility of focusing on treatment-relevant psychological constructs that characterize substance abusers with borderline personality disorder.

Knowledge regarding the steps and mechanisms related to the intra‐ and interchain cross‐linking of collagen and elastin has evolved steadily during the past 30 years. Recently, effort has been directed at identifying the location and types of cross‐links that are found in collagen and elastin. There are two major groups of cross‐links: those initiated by the enzyme lysyl oxidase and those derived from nonenzymatically glycated lysine and hydroxylysine residues. The formation of enzymatic cross‐links depends on specific enzymes, amino acid sequences, and quaternary structural arrangements. The cross‐links that are derived nonenzymatically occur more adventitiously and are important to pathobiological processes. Considerable progress has been made in elucidating the pathways of synthesis for several of the enzymatically mediated cross‐links, as well as possible mechanisms regulating the specificity of cross‐linking. Although less is known about the chemistry of cross‐links arising from nonenzymatically glycated residues, recent progress has also been made in understanding possible biosynthetic pathways and control mechanisms. This review focuses on such progress and hopes to underscore the biological importance of collagen and elastin cross‐linking.—Reiser, K.; McCormick, R. J.; Rucker, R. B. Enzymatic and nonenzymatic cross‐linking of collagen and elastin. FASEB J.6: 2439‐2449; 1992.

Barclay: New scientific knowledge and resultant technologies create ethical dilemmas for society. The potential applications of in utero surgery for the repair of fetal defects are enormous and raise interesting ethical questions. The work of Drs Hodgen and Michejda and their associates, such as fetoscopic insertion of a prosthesis to relieve intracranial pressure in the hydrocephalic fetus and closure of neural tube defects, represents important advances and will be the context of our discussion today.McCormick: As part of any full discussion of an issue like this, something that strikes me is the need to distinguish among technologies. How is in utero surgery similar or dissimilar to end-stage renal disease programs, cardiac bypass surgery, and so on? In many such procedures, we are dealing with people who have lived fairly full lives, and we are not changing life radically, in terms of mentation or freedom. With the technology under discussion,

The importance of coping skill enhancement in the treatment of pathological gamblers is discussed. It is particularly critical to assess and enhance the coping skills of relapse prone gamblers who are marked by unusual degrees of impulsivity, high levels of negative affect and feelings of helplessness and hopelessness. A study of 1129 substance abusers, including 140 with serious gambling problems is reported. All were assessed to determine their repertoire of coping skills. The patients with serious gambling problems utilized significantly more avoidant and impulsive coping styles.

The model proposed attempts to integrate the growing data base on pathological gamblers in a parsimonious manner. The model focuses on psychological observations, although it recognizes the parallel importance of physiological phenomena. The model is based on two recurring observations with pathological gamblers: Gambling satisfies recurring and often intensified needs for the gambler; and pathological gamblers vary tremendously on a number of dimensions. The model suggests that attempts to understand pathological gambling must focus on sub-types of pathological gamblers. Two sub-types, are discussed.

This paper argues that there area priori reasons to extract measures of ego strength and achievement motivation from the psychometric data base routinely collected from inpatient pathological gambers in order to clarify the meaning of these constructs and to evaluate their roles in personality organization. A sample of 57 subjects engaged in an inpatient treatment program for pathological gamblers was studied using Barron's Ego Strength Scale (ES) from the Minnesota Multiphasic Personality Inventory and two measures of achievement motivation from the California Personality Inventory, Achievement via Conformance (Ac) and Achievement via Independence (Ai). Compared to the standardization group norms on these instruments, pathological gamblers are significantly deficient in both ego strength and one type of achievement motivation, Ac. Clinical impressions of gamblers in treatment suggest that narcissistic characteristics are a major problem in treatment and that future research should attempt further detailed studies of ego structure in order to refine treatment objectives.

Major traumatic events were discovered in the histories of 23% of pathological gamblers seeking hospital treatment. These high-trauma patients were compared with groups of gambler patients who had experienced insignificant, low, or moderate amounts of life trauma. High-trauma patients tended, as measured by standard psychometrics, to be more depressed, anxious, and avoidant in personality style; they were also more likely to be abusing alcohol or other drugs. In their discussion the authors focus on the concept of learned dysthymia, a chronic state of negative affect related to cumulative life trauma and seemingly instrumental in potentiating addictive euphoria.

To explore the use of normal personality measures in clinical populations, we investigated the usefulness of the Five-Factor personality domains measured by the NEO Personality Inventory (NEO-PI) in identifying subtypes among a cohort of 3,256 substance abusers. Three groups were reliably identified across clustering methods and the groups differed in reported coping style, psychopathological symptoms, and pattern of substance choice. The largest differences between group members' personality dimensions were found for measures of neuroticism, agreeableness, and conscientiousness. Members of groups characterized by elevated levels of neuroticism demonstrated low levels of conscientiousness and agreeableness. The more extreme the group members' levels on these personality dimensions, the higher their reported levels of depressive symptoms, aggressive/hostile cognitions, impulsiveness, maladaptive coping styles, and likelihood of abusing more than one substance. Results support the use of measures of normal domains of personality in identifying meaningful subtypes of substance abusers.

This paper evaluates direct filtration as a treatment method for water from five sources in Virginia. The most effective filtration scheme consisted of a three‐minute rapid mix with alum and a cationic polymer used in combination as primary coagulants. The rapid mix was followed by filtration at 3.5 mm/s (5 gpm/sq ft) through 51 cm (20 in.) of 1.3‐mm effective size (e.s.) anthracite coal and 25 cm (10 in.) of 0.45‐mm e.s. silica sand. This configuration produced filtered water that met the AWWA goal for turbidity with filter run times of at least eight hours when color and turbidity in the raw water were less than 15–20 units.