Are postoperative antibiotics required after orthognathic surgery?

The aim of this study was to investigate and compare the frequency of surgical site infection (SSI) between orthognathic patients who received only intraoperative antibiotics and patients who received intraoperative antibiotics plus postoperative antibiotics. A retrospective study was performed of patients treated by a single surgeon over the years 2006-2012 and 2016-2019. The primary predictor variable was antibiotic exposure. The control group received no postoperative prophylactic antibiotics. The study group received postoperative antibiotics. Both groups received prophylactic intraoperative antibiotics and performed postoperative chlorhexidine rinses. The primary outcome was SSI frequency. Univariate, bivariate, and multiple logistic regression analyses were performed; statistical significance was set at P ≤ 0.05. The sample comprised 333 patients. Their mean age was 30.7 ± 11.8 years. The study group included 129 patients (38.7%); the control group included 204 patients (61.3%). The frequency of SSI was 17.1% in the study group and 26.5% in the control group (P = 0.048). In the multivariable logistic regression, only alcohol consumption was significantly associated with an increased risk of SSI (odds ratio 2.46, 95% confidence interval 1.36-4.44; P = 0.003). In patients undergoing orthognathic surgery, postoperative antibiotic exposure in addition to intraoperative prophylaxis approached but was not statistically significant for a decreased risk of SSI (P = 0.067).

Influence of electronic resonances on mode selective excitation with tailored laser pulses.

Femtosecond time-resolved coherent anti-Stokes Raman scattering (fs-CARS) gives access to ultrafast molecular dynamics. However, the gain of the temporal resolution entails a poor spectral resolution due to the inherent spectral width of the femtosecond excitation pulses. Modifications of the phase shape of one of the exciting pulses results in dramatic changes of the mode distribution reflected in coherent anti-Stokes Raman spectra. A feedback-controlled optimization of specific modes making use of phase and/or amplitude modulation of the pump laser pulse is applied to selectively influence the anti-Stokes signal spectrum. The optimization experiments are performed under electronically nonresonant and resonant conditions. The results are compared and the role of electronic resonances is analyzed. It can be clearly demonstrated that these resonances are of importance for a selective excitation by means of phase and amplitude modulation. The mode selective excitation under nonresonant conditions is determined mainly by the variation of the spectral phase of the laser pulse. Here, the modulation of the spectral amplitudes only has little influence on the mode ratios. In contrast to this, the phase as well as amplitude modulation contributes considerably to the control process under resonant conditions. A careful analysis of the experimental results reveals information about the mechanisms of the mode control, which partially involve molecular dynamics in the electronic states.

The effect of perinatal hormonal imprinting with 13-cis-retinoic acid (isotretinoin) on the thymic glucocorticoid receptors of female and testosterone level of male adult rats.

In earlier experiments, the long-term effect of perinatal treatment (hormonal imprinting) with all-trans-retinol and all-trans-retinoic acid on the thymic glucocorticoid and uterine estrogen receptors was studied and was found effective. In the present experiments, the imprinting effect of four retinoids (13-cis-retinaldehyde, 13-cis-retinoic acid, 9-cis-retinaldehyde and 9-cis-retinoic acid) was investigated, using receptor kinetic analysis and sexual hormone (testosterone and progesterone) level determinations. Exclusively 13-cis-retinoic acid (isotretinoin) had an effect, significantly decreasing glucocorticoid receptor affinity and increasing serum testosterone level. Relationships with RAR-RXR receptor binding and teratogenicity is discussed.

Prolonged elevation of insulin content in the unicellular tetrahymena after insulin treatment: induction of insulin production or storage?

In the unicellular organism, Tetrahymena, the first encounter with an exogeneously given hormone results in hormonal imprinting. This causes an increase of the binding capacity of receptors and the production of the appropriate hormone in the progeny generations of the treated cell. In the present experiments the quantity (using radioimmunoassay) and localization (using confocal laser scanning microscopy) of the immunologically insulin-like material (hereafter insulin) were studied for 10 days after 4 h or 24 h 10(-6) M insulin treatment (hormonal imprinting). Forty-eight hours after both insulin treatments a high quantity of insulin was present in the cells. This value was also significantly increased after 96 h. After 8 days the difference to the control was significant only in the 24 h treated group. Confocal microscopy (using antibody to pig insulin) localized insulin in the cell body. The oral field contained extremely high quantities of the endogeneous hormone. Insulin treatment (after 48 and 96 h) caused an elevation of insulin content in general, and specific accumulation in the posterior sections of the cell, around the nucleus and in the periphery were observed. Ten days after both treatments only the peripheral region of the cell body and the ciliary row contained more insulin than the control. This means that after insulin treatment the quantity of insulin increases for a lengthy time period which is followed by the expression of insulin in the peripheral region. Insulin contained by Tetrahymena 48 h after imprinting stimulated glucose uptake of rat diaphragm.

Effect of retinoid (vitamin A or retinoic acid) treatment (hormonal imprinting) through breastmilk on the glucocorticoid receptor and estrogen receptor binding capacity of the adult rat offspring.

Hormonal imprinting occurs perinatally when the developing receptor and the appropriate hormone meet each other. The presence of related molecules in this critical period causes misimprinting. Ligands bound to a member of the steroid-thyroid receptor superfamily can disturb the normal maturation of other members of the family, which is manifested in altered binding capacity of the receptor and decreased or increased response of the receptor-bearing cell for life. Excess or absence of the hormone also can cause misimprinting. Treatments once a week for 3 weeks of nursing rat mothers with 6 mg/animal all-trans retinol/dose caused faulty imprinting manifested in significantly reduced density (Bmax) of thymic glucocorticoid receptor in male and female adult progenies alike. 0.03 mg all-trans retinoic acid treatment of nursing mothers was ineffective. Receptor affinity (Kd) was unchanged in both cases as well, as the binding values of uterine estrogen receptors. The results of the experiment call attention to the transmission of imprinter molecules by breastmilk to the progenies, which can cause lifelong alterations at receptorial level and points to the human health aspect. Possible reasons for the differences between retinol and retinoic acid effects and in the sensitivity of receptors are discussed.

Testosterone and progesterone level alterations in the adult rat after retinoid (retinol or retinoic acid) treatment (imprinting) in neonatal or adolescent age.

Newborn rats were treated with a single dose of vitamin A (retinol), or with three doses of retinoic acid (in the 1st, 3rd and 5th days). Serum testosterone and progesterone level was measured in the four months old male and female rats, respectively. Retinol significantly decreased both hormone levels, however retinoic acid decreased the progesterone level only. In the second part of the experiments adolescent rats (in the 6th and 7th week after birth) were treated and measured similar to the newborns. In this case retinol significantly diminished testosterone level, without influencing the progesterone level. Retinoic acid decreased testosterone level and elevated progesterone level. The results demonstrate the long lasting effects of retinoid treatments at a neonatal or adolescent age, pointing also to the differences in the direction of the effects. Considering that previously the receptorial and sexual-behavioral effects of perinatal vitamin A treatments were observed, the experiments call attention to such harmful influences of perinatal vitamin A treatments, which are not manifested in morphological alterations.

Effect of perinatal vitamin A or retinoic acid treatment (hormonal imprinting) on the sexual behavior of adult rats.

Single neonatal treatment with vitamin A (retinol) dramatically reduced the sexual activity of adult male rats. In females there was a significant decrease in the Meyerson index and a non significant decrease in the lordosis quotient. The effect of three perinatal treatments (at the first, third and fifth day) with all-trans retinoic acid was much weaker, causing only a significant increase in the time of the first ejaculation in males and non-significant decrease in the lordosis quotient of females. The experiments call attention to the false imprinting provoking effect of materials acting on members of the steroid receptor superfamily with possible human health aspect.

Increased apoptosis of adult rat lymphocytes after single neonatal vitamin A treatment (hormonal imprinting). A flow cytometric analysis.

Newborn rats were treated with a single dose of vitamin A (retinol) and apoptosis of peripheral lymphocytes was studied by flow cytometry in adult age. Vitamin A treatment (hormonal imprinting) caused a moderate, however significant elevation in the number of apoptotic lymphocytes after three months. Dexamethasone or Concanavalin-A alone did not influence apoptosis significantly. However, in the neonatally retinol treated rats dexamathasone significantly elevated the quantity of apoptotic lymphocytes related to the control or Concanavalin-A treated control cells. The results call attention to the prolonged effect of hormonal imprinting in a new index and to the possible dangerous effects in human, neonatally treated with vitamin A.

Nondenaturing protein electrotransfer of the esterase activity of lipolytic preparations.

Lipolytic enzymes subjected to nondenaturing polyacrylamide gel electrophoresis were electrophoretically transferred under nondenaturing conditions onto a solid-state matrix. Electrotransfer permitted the visualization of hydrolytic activity to the long-chain water insoluble substrate alpha-naphthyl palmitate. Four commercial preparations: a lipase from Candida cylindracea, an esterase from porcine liver, a lipase from Pseudomonas sp., and a cholesterol esterase from Pseudomonas fluorescens were examined.

High-resolution separation and accurate size determination in pulsed-field gel electrophoresis of DNA. 3. Effect of electrical field shape.

The resolution of pulsed-field gel electrophoresis is dramatically affected by the number and configuration of the electrodes used, because these alter the shape of the applied electrical fields. Here we present calculations and experiments on the effect of electrode position in one of the most commonly used pulsed-field gel electrophoresis configurations. The goal was to explore which aspects of the electrical field shape correlate with improved electrophoretic resolution. The most critical variable appears to be the angle between the alternate electrical fields. The most effective electrode configurations yield angles of more than 110 degrees. A continually increasing angle between the fields produces band sharpening that greatly enhances the resolution.

Uniformly spaced banding pattern in DNA sequencing gels by use of field-strength gradient.

A method is described for casting and operating ultrathin wedge-shaped field-strength gradient gels for DNA sequencing. One of the gradients results in a uniformly-spaced oligonucleotide banding pattern from 60 to 300 nucleotides in a 53 cm long 4% polyacrylamide gel. From these field-strength gradient gels, more sequencing data can be obtained with greater confidence than from gels with uniform thickness. The gel-casting method is fast and simple. At 2.5 kV two gels can be run simultaneously in 2 h with the same power supply.

Induction of phenol-metabolizing enzymes in Trichosporon cutaneum.

Some aspects of the induction of enzymes participating in the metabolism of phenol and resorcinol in Trichosporon cutaneum were studied using intact cells and cell-free preparations. Activities of phenol hydroxylase (1.14.13.7), catechol 1,2-oxygenase (1.13, 11.1), cis-cis-muconate cyclase (5.5.1.-), delactonizing enzyme(s) and maleolylacetate reductase were 50-400 times higher in fully induced cells than in noninduced cells. In addition to phenol and resorcinol, also catechol, cresols and fluorophenols could induce phenol hydroxylase. The induction was severely inhibited by phenol concentrations higher than 1 mM. Using optimum inducer concentrations (0.01-0.10 mM), it took more than 8 h to obtain full induction, whether in proliferating or in nonproliferating cells. Phenol hydroxylase, catechol 1,2-oxygenase and cis, cis-muconate cyclase were induced simultaneously. The synthesis of the de-lactonizing activity was delayed in relation to these three preceeding enzymes of the pathway. High glucose concentration (over 15 mM) inhibited completely the induction of phenol oxidation by nonproliferating cells. It also inhibited phenol oxidation by pre-induced cells. Among the NADPH-generating enzymes, the activity of iso-citrate dehydrogenase was elevated in cells grown on phenol and resorcinol instead of glucose.

cis,cis-Muconate cyclase from Trichosporon cutaneum.

The inducible enzyme catalysing the conversion of cis,cis-muconate to (+)-muconolactone was purified 300-fold from the yeast Trichosporon cutaneum, grown on phenol. The enzyme has a sharp pH optimum at pH 6.6. It reacts also with several monohalogen derivatives and with one monomethyl derivative of cis,cis-muconate, but not with cis,trans- or trans,trans-muconate or 3-carboxy-cis,cis-muconate. In contrast with the corresponding enzymes in bacteria, the yeast enzyme does not require added divalent metal ions for activity and is not inhibited by EDTA. The purified enzyme can be resolved into two peaks by isoelectric focusing. The two forms have pI 4.58 (cis,cis-muconate cyclase I) and pI 4.74 (cis, cis-muconate cyclase II), respectively. Each of these is homogenous on polyacrylamide-gel electrophoresis in the absence or presence of sodium dodecyl sulphate. The two enzyme forms have the same molecular weight (50000) as determined by gel filtration and by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. They have the same Km value (25 microM) for cis,cis-muconate. They differ with respect to their content of free thiol groups. cis, cis-Muconate cyclase I contains one thiol group, essential for activity, but relatively stable upon storage. cis, cis-Muconate cyclase II contains two thiol groups that are readily oxidized during storage with concomitant loss of activity.

Maleylacetate reductase from Trichosporon cutaneum.

The enzyme catalysing the reduction of maleylacetate to 3-oxoadipate was purified 150-fold from Trichosporon cutaneum, induced for aromatic metabolisms by growth with resorcinol as a major carbon source. The enzyme separated upon electrofocusing into three species with PI values 4.6, 5.1 and 5.6. They had similar catalytic properties and the same molecular weight.

Metabolism of phenol and resorcinol in Trichosporon cutaneum.

Trichosporon cutaneum was grown with phenol or resorcinol as the carbon source. The formation of beta-ketoadipate from phenol, catechol, and resorcinol was shown by a manometric method using antipyrine and also by its isolation and crystallization. Metabolism of phenol begins with o-hydroxylation. This is followed by ortho-ring fission, lactonization to muconolactone, and delactonization to beta-ketoadipate. No meta-ring fission could be demonstrated. Metabolism of resorcinol begins with o-hydroxylation to 1,2,4-benzenetriol, which undergoes ortho-ring fission yielding maleylacetate. Isolating this product leads to its decarboxylation and isomerization to trans-acetylacrylic acid. Maleylacetate is reduced by crude extracts to beta-ketoadipate with either reduced nicotinamide adenine dinucleotide or reduced nicotinamide adenine dinucleotide phosphate as a cosubstrate. The enzyme catalyzing this reaction was separated from catechol 1,2-oxygenase, phenol hydroxylase, and muconate lactonizing enzyme on a diethyl-aminoethyl-Sephadex A50 column. As a result it was purified some 50-fold, as was the muconate-lactonizing enzyme. Methyl-, fluoro-, and chlorophenols are converted to a varying extent by crude extracts and by purified enzymes. None of these derivatives is converted to maleylacetate, beta-ketoadipate, or their derivatives. Cells grown on resorcinol contain enzymes that participate in the degradation of phenol and vice versa.

Phenol hydroxylase from yeast. Sulfhydryl groups in phenol hydroxylase from Trichosporon cutaneum.

Thiol groups in phenol hydroxylase were measured using two different -SH reagents and amino acid analysis. Stepwise blocking of the -SH groups was correlated with enzyme activity and FAD content. The results indicate that the enzyme contains 16 -SH groups per molecule of Mr 1.48 X 10(5). At least four -SH groups are not accessible without the use of a denaturing agent. There is seemingly no disulphide bridge. On the whole, the reactivity towards p-hydroxymercuribenzoate is much greater than towards 5,5'-dithio-bis(2-nitrobenzoic acid). The two reagents seem to have a different specificity with respect to which -SH groups they attack. Either reagent dislocates FAD from the holoenzyme, leaving a characteristic mercaptide derivative of the apoenzyme. Such derivatives were used to prepare the apoenzyme. The -SH groups in the apoenzyme are much more reactive towards 5,5'-dithio-bis(2-nitrobenzoic acid) than the -SH groups in the holoenzyme. The stoichiometry of the reaction with 5,5'-dithio-bis(2-nitrobenzoic acid) indicates that at least 8 -SH groups are located in spatially close pairs. The most reactive pair of all does not appear to be of importance for enzyme activity. The two subsequent -SH pairs are essential for enzyme activity are are involved in FAD attachment. The reactivity of the -SH groups decreases dramatically in the presence of substrate, even at substrate concentrations equivalent to the level of the catalytic sites. The isolated apoenzyme has a tendency to aggregate. A large proportion of -SH groups in such aggregate(s) is buried, especially when EDTA is not used throughout the preparation of the apoenzyme. The aggregates are enzymically inactive.

Serum IgM immunoglobulin in neonatal enteritis.

The serum IgM immunoglobulin level has been studied in 106 newborns admitted with enteritis of various aetiology. The clinical characteristics of E. coli K86 and K59 enteritis as well as those of aspecific enteritis are discussed. The epidemic caused by E. coli K86 was the first of its kind observed in Hungary. Mature, dysmature and preterm newborns were all capable of increased IgM production under the effect of an antigenic stimulus. Serial examinations showed a rapid and considerable rise of IgM concentration in the initial, active phase of the disease. The rise was significant statistically and the level remained constant in the course of the disease and during convalescence. The importance of prevention is emphasized, especially as fatal septicaemia may develop on the basis of the existing or of a new infection, in spite of careful nursing and drug therapy.