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PubMed2002

Surgical management of severe pancreatitis including sterile necrosis.

BACKGROUND/PURPOSE: Severe pancreatitis develops in 15% to 20% of patients with acute pancreatitis, morphologically characterized by extra- and intrapancreatic necrosis and associated with single or multiple organ failure. It is well accepted that surgery is indicated in patients with infected pancreatic necrosis. However, management of sterile necrosis is still controversial. In a prospective study, we evaluated the effect of maximal intensive care unit (ICU) treatment combined with prophylactic antibiotics in patients with necrotizing pancreatitis. METHODS: A total of 306 consecutive patients with acute pancreatitis were hospitalized between November 1993 and August 2001. All patients with necrotizing pancreatitis diagnosed by computed tomography received ICU treatment, including antibiotics (imipenem/cilastin). Fine-needle aspiration of pancreatic necrosis was performed in patients with clinical signs of sepsis, and necrosectomy combined with continuous postoperative lavage was indicated when bacterial testing demonstrated infection. In the presence of sterile necrosis, surgery was only performed when there was no clinical improvement despite maximal ICU treatment. RESULTS: Necrotizing pancreatitis was found in 121 patients. Infected necrosis was verified in 41 patients (34%) at a mean of 26 days. Four percent of patients with sterile necrosis and 95% of patients with infected necrosis were operated on. The surgical procedure was successful in 83% of patients as a single intervention; relaparotomy had to be performed in only 7 patients (17%). Pancreatic abscesses were found in 7 patients; four of these were drained interventionally. The overall mortality of the patients with necrotizing pancreatitis was 9.9%. The mortality of patients with sterile and infected necrosis was 2.5% and 24%, respectively (sterile vs infected; P < 0.01). CONCLUSIONS: Due to improved intensive care treatment, including prophylactic antibiotics, surgical intervention is usually not indicated in the early course of severe acute pancreatitis. Surgery is clearly indicated in patients with proven infected necrosis. Patients with sterile necrosis should undergo surgery when there is no clinical improvement within 4 weeks of intensive care treatment. In the majority of patients a single intervention is sufficient. Reinterventions are rare and even in patients with abscess formation are not needed, because these can easily be drained interventionally.

Antibiotic Prophylaxis↗
PubMed1989

The interaction between X-rays and transposon mobility in Drosophila: hybrid sterility and chromosome loss.

Genetic traits associated with P-M hybrid dysgenesis in Drosophila melanogaster were synergistically affected by X-rays. The interaction between damages induced by these two mutator systems was evident when sterility and X/Y chromosome loss were used as endpoints. No interaction was detected in partial chromosome loss, monitored by the loss of BS and y+ markers. The synergism in sterility, measured either as all-or-none or premature sterility (fecundity) was observed when male hybrids derived from different P strains fathers, namely Harwich or II2, were X-irradiated and the effects compared relative to similarly treated non-dysgenic hybrids. Brooding of sperm showed that the effects of ionizing radiation were ionizing radiation were dependent upon the stage of spermatogenesis during which cells were irradiated. The highly synergistic effect on sterility was found when either spermatids or spermatocytes, but not mature sperm, were irradiated with 550 rad of X-rays. These findings were consistent with the higher radiosensitivity of spermatocytes and spermatids to genetic damage and with the correlation between the incidence of sterility and aging of dysgenic hybrids. The latter observation was particularly evident in the case of Harwich P strain-derived male hybrids whose fertility was greatly reduced due to P element mobility. The synergistic effect of X-rays in these dysgenic hybrids resulted in the virtual abolition of the germ line, increasing the sterility from 50% of the untreated 9-10-day old males, to 85% of the treated males when spermatocytes were irradiated. The synergism observed between transposon mobility and ionizing radiation can best the attributed to an interaction between X-ray-induced and P element-induced chromosome breaks. This interpretation is consistent with the more than additive increase in X or Y chromosome loss in irradiated, Harwich P strain-derived hybrid sons. The induction of these events was 1.164% in dysgenic irradiated males as compared to 0.234% in X-irradiated nondysgenic hybrids and 0.40% in dysgenic untreated males. No synergism was observed in X/Y loss in hybrids derived from II2 P strain fathers where the frequency of the events due to P element mobility alone was only one tenth (0.037%) of that found in Harwich-derived hybrids.

Animals↗
PubMed1993

Subcutaneous sterile water injections for chronic neck and shoulder pain following whiplash injuries.

In many cases of whiplash injury symptoms persist and do not respond to treatment. There is uncontrolled evidence to suggest that intracutaneous injections of sterile water might help. Since that route may be unacceptable to patients the subcutaneous route is used in the randomised trial reported here. 40 patients with whiplash syndrome, mean age 46 years (24-73) were given subcutaneous injections of 0.3-0.5 ml sterile water or saline over tender and trigger points in the neck and shoulder. A maximum of three treatments were given during the first two months of the study and the patients were followed up for 8 months. The accidents had occurred 4-6 years previously. X-ray examinations revealed no traumatic spinal lesions. Neck mobility and pain levels were evaluated by a physiotherapist immediately before and after the first treatment and after 1, 3, and 8 months. After 3 months, the mean total mobility of the cervical spine had increased by 39 degrees in the sterile water group and 6 degrees in the saline group (p < 0.05). Minimum and maximum levels of pain in the weeks just before treatment were evaluated by a visual analogue scale from 0 to 10. After 3 months the minimum pain level had fallen from 2.2 to 1.4 in the sterile water group but was not reduced in the saline group (p < 0.02); the maximum had fallen from 8.1 to 3.8 in the sterile water group and from 8.3 to 7.5 in the saline group (p < 0.001). After 3 months, 19 of 20 patients in the sterile water group assessed their condition as generally improved but only 6 in the saline group felt that they had got better. After 8 months there were still significant differences for minimum pain score and for mobility but not for maximum pain or for self-assessment of improvement.

Adult↗
PubMed2006

Sterilization of gentamicin containing collagen/PLGA microparticle composites.

In order to achieve implants which provide sustained release of gentamicin, microparticles based on a 50/50 Resomer 503/Resomer 502H blend were combined with collagen in order to achieve their fixation and to utilize the favorable effect of collagen on wound healing. Ethylene oxide treatment as well as beta- and gamma-irradiation were tested for sterilization of the collagen/PLGA-microparticle composite. All methods resulted in a decrease of molecular weight and glass transition temperature of polymer raw material and microparticles. In addition, ethylene oxide treatment yielded aggregation of microparticles leading to a substantial increase in the initially liberated gentamicin dose. Furthermore, chemical changes of gentamicin after ethylene oxide sterilization could be identified using NMR spectroscopy. Despite a decrease in the molecular weight and glass transition temperature after irradiation, neither morphological changes of the composites nor changes regarding the gentamicin release profile from beta- and gamma-sterilized material were observed. Free radicals, which could only be detected in gentamicin drug substance and at marginal level in gentamicin-loaded MPs, disappeared within 4 weeks. Additional microbiological testing verified the microbiological activity of gentamicin liberated from beta-sterilized composites. Storage of beta-sterilized composite at 4 degrees C/35% r.h. for 3 months did not influence morphology, molecular weight, glass transition temperature, and release profiles of microparticles and composites. However, at 25 degrees C/60% r.h. and 40 degrees C/75% r.h. a marked decrease in molecular weight and glass transition temperature resulted. This effect was due to a higher humidity, water uptake into polymers, and subsequent hydrolysis of polymers and microparticles, which was more pronounced for RG 502H because of its hydrophilicity. Upon storage at 25 degrees C/60% r.h. and 40 degrees C/75% r.h. particles collapsed resulting in an increased gentamicin liberation. Thus, all sterilization techniques have their pros and cons, but based on drug release profile and chemical changes of gentamicin irradiation treatment appears to be more suitable for collagen/gentamicin-loaded PLGA microparticle composites.

Beta Particles↗
PubMed2007

Heterologous expression of the mutated melon ethylene receptor gene Cm-ERS1/H70A produces stable sterility in transgenic lettuce (Lactuca sativa).

The mutated melon ethylene receptor gene Cm-ERS1/H70A was introduced into tobacco and induced stable sterility in transgenic lines. This gene contains a missense mutation that converts the His(70) residue to Ala in the melon ethylene receptor gene Cm-ERS1. To test the applicability of this inducible sterility system to other plants, lettuce (Lactuca sativa) was transformed with the gene using Agrobacterium, and putative transformants containing Cm-ERS1/H70A were obtained. Thirteen randomly selected putative transformants were grown in a growth room under constant conditions, and seven of the lines showed sterility or significantly reduced fertility. DNA gel blot analysis confirmed the integration of the Cm-ERS1/H70A gene into the genomes of the putative transformants, and RT-PCR and protein gel blot analysis confirmed the expression of Cm-ERS1/H70A mRNA and protein in all of the transformants. Five transformants showing sterility or reduced fertility when grown in a growth room under constant conditions were randomly selected to be grown in an open-air greenhouse under various environmental conditions. All five showed stable sterility under the various conditions. These results suggest that Cm-ERS1/H70A can induce sterility in heterologous transgenic plants.

Agrobacterium tumefaciens↗
PubMedDate not supplied

[Study on psychiatric disorders and defensive process assessed by the "defense style questionnaire" in sterile males SAMPLE consulting in andrology].

BACKGROUND: The literature about artificial insemination and the associated psychological, psychiatric and sexual disorders is relatively rich. But the majority of these studies is made in gynaecology, with a feminine approach of the disorder. There are very few works led in andrology. This justified the investigation of new trails in order to understand better the clinical context of the sterile man. We undertake a study about the psychiatric disorders among sterile men and about the defense styles. These are a clinical entity recently introduced in the quantitative psychopathology research. The defense style questionnaire (DSQ) is a psychometric scale used in common practice in order to measure the defense styles. OBJECTIVES: We made this study in order to examine the psychiatric state of a sterile males sample consulting in andrology; to assess the defense style by means of the Bond and al DSQ-88 ; to look into a difference between the defensive process according to their clinical situation of azoospermic males or as the oligoazoospermic males and finally, to reveal a correlation between the psychiatric disorders developed in this sample of sterile males and the defensive process they used. METHOD: There were 42 people (22 azoospermic males and 20 oligoazoospermic males) aged between 23 and 49 years old in the analysed sample. These have been selected at the surgery of andrology at the RUHC of Lille, depending on their arrival order for 6 months. There was no significant difference between the two groups as far as the age and the education standard are concerned. The selection criteria were medical and somatic. Our sample population were divided into two groups: azoospermia (no spermatozoon found in the semen analysis) and oligoasthenospermia (decrease of the number and the mobility of the spermatozoa and an increase of the percentage of atypical forms). The method first consisted in the DSQ, followed by the analysis of the psychiatric state according to the DSM IV, a hetero questionnaire to collect some general information about infertility and a self questionnaire about the sexual, conjugal and social effects of infertility. The DSQ and the interviews took place in the andrology department with the same investigator trained for this job. RESULTS: We found in our sample 26.2% of psychiatric disorders according to the DSM IV with a significant over-representation of generalized anxious disorder and somatization disorder. The comparison between azoospermic males and oligoazoospermic males patients showed the absence of significative difference as far as psychiatric morbidity rate and the use of defense styles are concerned. DISCUSSION: Our sample defended himself in accordance with modalities similar to the general population and used defense mechanisms preferentially belonging to the mature defense style, such as humor, repression and anticipation. The psychiatric pathology was significantly correlated to the preferential use of withdrawal, consumption, reaction formation and lack of humor use. We also confirm in our study the fact that the subjects using especially neurotic defense styles are more likely to develop a psychiatric disorder than the others. Our male sample is a waiting population and threatened by failure. The situation of wait creates anxiety. We also know that infertility is one of the most stressful situations a couple might face. However, our study did not enable us to know the precise relations between generalized anxious disorder and infertility, especially whether the generalized anxious disorder preceded this pathology or not. The over-representation of a somatization disorder only allows us to acknowledge its existence. We can also deduce from that a possible link between infertility and psychic disorder, even if no research permitted to affirm to date the existence of interrelations linking infertility and psychic life. On the whole, this population was suffering despite 73.8% of the patients had no confirmed psychiatric disorder. It is the reason why a liaison psychiatry more inserted into highly specialized teams is interesting, especially because it includes a medical and psychological approach of such disorders. The defense mechanisms preferentially used by this population were humor, repression and anticipation. Humor can only be considered as a defense mechanism when it is applied to oneself. The population who has no psychiatric disorder more uses humor. Does humor protect against the development of a psychiatric pathology, as certain authors proved it ? On the other hand, is repression really protective? It didn't interfere in our study about the development of a psychiatric pathology. So we can suppose that repression was protective for our whole sample, but we can not prove it. However, we wonder if this mechanism works after the failure of an artificial insemination is announced. In which measure such a stress can be repressed out of the conscience field? As for anticipation, it is used by our population who is for the most part in good health. But the question is to know if our sample really envisaged all the different possible solutions or only the success of artificial insemination. As some other works, we confirm that the, psychiatric, people significantly use the neurotic style. Our psychiatric patients used less humor and more consumption, withdrawal and reaction formation than the sane people. Consumption is rarely considered as a defense mechanism by some other authors. And yet, consumption and the existence of psychiatric disorders were very closely linked. This association is found again with anxiety in other studies. The correlation between psychiatric disorder and withdrawal was veryimportant too. The DSM lV defines withdrawal as an apathetic withdrawal. It is not an apathetic withdrawal in our population because the average scores for the ,, activity >, defense mechanism remained high. In our sample, the use of this defense mechanism would encourage the expression of psychiatric troubles. The reaction formation quoted by Freud and Bergeret are both valorised in our society. What kinds of reaction formations use these men ? Are they pathological ? Our study can not answer to these questions. However, the DSQ items examining the reaction formation present its "socially promoted" aspect and forget the pathological one. It has been showed that the evaluation of the defense modalities in a certain type of population can allow the emergence of specific defense mechanisms. This can be considered as predictive factors of development of a mental pathology. The evaluation of specific mental defenses could permit to define vulnerability and affinity for given affections instead of simple personality traits or profiles. Most part of the works shows results in favour of the capacity of DSQ to assess the different defense mechanisms according to the diagnosis groups. But the insufficient numbers of studies moderate on the whole the hypothesis of the existence of specific defense mechanisms--protective factors and factors of vulnerability--linked to a given psychiatric disorder. CONCLUSION: There is not a difference of psychological effect in terms of degree of sterility. On the other hand, the existence of over-represented psychiatric disorders with sterile males compared with a control group force Consultation-Liaison psychiatrists and andrologists would be able to understand the pain beyond the need of acting by the artificial insemination. In our opinion, this justifies the fact that the patients should have the opportunity of expressing, in the department where they are treated, all the feelings inherent to their personal and conjugal drama as part of a specialized treatment. Our study confirms the difficulty to know whether some defense mechanisms are vulnerability factors for a certain psychiatric disorder or whether the defense mechanisms are an epiphenomenon of a particular psychiatric disorder. This is the reason why a lot of authors having worked with DSQ agree to conclude that additional prospective studies, which would permit to make a link between the defense mechanisms anda certain psychiatric pathology, are necessary. In the case we study, it is important to explore the defensive modalities before the infertility diagnosis and after the birth of a child, with a more important sample population. A better knowledge of the defensive modalities of such a population, used in a psychotherapeutic context could help to prevent the appearance of psychiatric disorders or, if not, to anticipate them.

Adaptation, Psychological↗
PubMed2000

Male-sterile tobacco displays abnormal mitochondrial atp1 transcript accumulation and reduced floral ATP/ADP ratio.

Alloplasmic male sterility is commonly obtained in Nicotiana by combining the nucleus from N. tabacum with the cytoplasm from other Nicotiana species. Besides being male-sterile, most of these cultivars also display changes in floral organ structure. Flowers from male-sterile plants containing the nucleus from N. tabacum combined with N. repanda cytoplasm develop stamen with shortened filaments and shrivelled anthers capped with stigmatoids. Male fertility and normal floral development can be restored by introduction of a restorer chromosome fragment from the cytoplasmic donor N. repanda into the N. tabacum nucleus. A novel reading frame, orf274, located upstream of atp1 in the mitochondrial genomes of both N. tabacum and N. repanda, as well as in the male-sterile and fertility-restored plants was identified. Co-transcripts of orf274 and atp1 were detected by RT-PCR in all four cultivars, but these transcripts accumulate to levels detectable by northern hybridization only in male-sterile plants. These co-transcripts neither generate detectable levels of an ORF274 polypeptide nor lead to altered expression of the ATP synthase subunit alpha. Measurement of ATP and ADP steady-state levels, however, revealed that the ATP/ADP ratio is significantly lower in young floral buds of male-sterile plants than in fertile plants.

Adenosine Diphosphate↗
PubMed1997

Comparison of the wear of aged and non-aged ultrahigh molecular weight polyethylene sterilized by gamma irradiation and by gas plasma.

The wear of ultrahigh molecular weight polyethylene in artificial joints is a major cause of long-term osteolysis and loosening. The wear rate of aged and non-aged ultrahigh molecular weight polyethylene sterilized by both gamma irradiation in air and gas plasma has been studied in simple configuration wear tests. Fourier transform infrared analysis (FTIR) showed marked oxidative degradation of the irradiated and aged material compared to the gas plasma sterilized and aged material. The wear rate of the irradiated and aged material was significantly (three times) higher than the gas plasma sterilized, gas plasma sterilized and aged, and non-sterilized materials. Alternative sterilization procedures such as gas plasma, when used instead of gamma irradiation in air, are likely to reduce the incidence of long-term osteolysis.

Journal Article↗
PubMed1979

The I-R system of hybrid dysgenesis in Drosophila melanogaster: influence on SF females sterility of their inducer and reactive paternal chromosomes.

A specific kind of sterile F1 female, denoted SF, arises when females from strains known as reactive are crossed with males from the complementary class of strains (inducer). It has been shown that this sterility results from the interaction between the maternal reactive cytoplasm and any one of the paternal inducer chromosomes. This interaction yields other dysgenic traits including non-disjunction and mutations. In this note, the abilities of paternal gametes containing various combinations of inducer and reactive chromosomes to give more or less sterile SF females when fertilising standard reactive oocytes were compared. Although they did not cause SF sterility, reactive chromosomes, when present in sperm containing at least one inducer chromosome, were found to influence the intensity of sterility: variations of SF sterility were observed between SF females which differed only by one paternally inherited reactive chromosome. Reactive chromosomes are known to control the cytoplasmic state of reactive females. The present results suggest that this chromosomal control also takes place in SF females.

Animals↗
PubMed1991

Sterility of male and female hybrids of Drosophila virilis and Drosophila lummei.

The sterility of interspecific hybrids between the sibling species Drosophila virilis and D. lummei was tested in reciprocal F1s and different second generation combinations of cytoplasm, sex chromosomes and autosomes. Males with motile sperm and females with at least one mature egg were scored as fertile. When D. virilis was the mother, about 5 per cent of the F1 male progeny was sterile, the reason being that the X of D. virilis was weakly incompatible with the heterozygous second, fourth and fifth chromosomes. The F1 males carrying the X chromosome of D. lummei were all fertile. The X chromosome of D. lummei, and in particular its species-specific double inversion In(1)a + b, nevertheless caused sterility in 70 per cent of males in the presence of homozygous autosomes of D. virilis. Sterility was rare among the females, although some weakly disadvantageous X versus autosome and autosome versus autosome interactions were detected. The male and female hybrid sterilities were based on different genetic systems. The results emphasize the central role of the X chromosome in hybrid male sterility.

Animals↗
PubMed1966

Microbial persistence. I. The capacity of tubercle bacilli to survive sterilization in mouse tissues.

A previously reported form of microbial persistence whereby large populations of tubercle bacilli can be made to "vanish" uniformly from the tissues of mice has been shown to occur generally throughout each group of animals subjected to the experimental procedure; it does not reflect the eradication of the bacilli in the majority of animals with their persistence and ultimate revival in only a minority. The one demonstrable alteration of the tubercle bacilli while "vanished" is that they are sterile. Thus, they are undetectable by cell-free culture, tissue culture, and blind animal passage, i.e. by any method based on microbial multiplication. Whether they have also undergone alteration in morphology and persist in some unconventional form cannot be stated. Acid-fast forms similar to tubercle bacilli can be detected in small numbers by intensified microscopic search of tissue homogenates but the relationship of these forms to the sterile bacilli that ultimately revive is unclear. Thus, the persisting tubercle bacilli are more correctly designated as being in a "sterile state" than one of true latency. The uniform induction of the sterile state is a specific phenomenon requiring the participation of both the nicotinamide derivative, pyrazinamide, and isoniazid. Once assumed, this sterile state is relatively stable and the time required for revival of the tubercle bacilli in the spleens in one-half the animals is seven months. This process can be speeded up by the administration of large doses of cortisone in the third or fourth month after sterilization but revival is not significantly affected by the administration of cortisone earlier.

Animals↗
PubMed1966

Microbial persistence. II. Characteristics of the sterile state of tubercle bacilli.

The capability of tubercle bacilli to assume a long continued sterile state in the tissues when exposed to pyrazinamide and isoniazid is a highly specific drug-microbe phenomenon in which host participation is not critical. Although it is the pyrazinamide that possesses the sterilizing type of action, the role of the isoniazid is specific and essential. The isoniazid serves to convert a phenomenon that occurs irregularly with pyrazinamide alone into one that occurs with a high degree of uniformity. The observations suggest a competition between isoniazid and the pyrazinamide (or its parent nicotinamide) for a site or entrance in or on the tubercle bacilli and for sterilization, the isoniazid apparently must reach the site first. The rare failures to attain complete sterilization, appear to depend on the emergence of pyrazinamide-resistance which prevents the necessary dependent action of the two drugs. Populations already in the sterile state are nevertheless subject to a continued drug influence. Whether this represents a direct action on the sterile bacilli or an indirect effect produced by making the environment hostile to microbial revival, cannot be determined from the present observations.

Animals↗
PubMed1994

Genetics of reproductive isolation in the Drosophila simulans clade: complex epistasis underlying hybrid male sterility.

We have analyzed the sterility associated with introgressions of the distal one-fourth of the X chromosome from either Drosophila mauritiana or Drosophila sechellia into the genome of Drosophila simulans using a series of visible and DNA markers. Because in Drosophila hybrids, male sterility is usually complete and is often tightly linked with each of several markers used in crosses, a simple genetic basis has generally been assumed. In our low resolution mapping experiment, we were not able to reject the null hypothesis that a single gene, introgressed from either D. mauritiana or D. sechellia, is the cause of male sterility. High resolution mapping, however, reveals a much more complex picture. At least three distinct factors from D. mauritiana, or two from D. sechellia, were identified that need to be jointly present to confer full sterility. Each individual factor by itself is relatively ineffective in causing sterility, or even a partial spermatogenic defect. Moreover, there appear to be more sterility factors on comparable introgressions from D. mauritiana than from D. sechellia. On the basis of these observations, we propose a model which suggests that multilocus weak allele interactions are a very common cause of reproductive incompatibility between closely related species. We also present theoretical argument and empirical evidence against extrapolating the results of within-species analysis to interpret the genetic basis of species differences. The implications of this model on the theories of evolution of species differences and the attempt to understand the mechanisms of hybrid sterility/inviability at the molecular level are discussed.

Animals↗
PubMed1996

Genetic architecture of autosome-mediated hybrid male sterility in Drosophila.

Several estimators have been developed for assessing the number of sterility factors in a chromosome based on the sizes of fertile and sterile introgressed fragments. Assuming that two factors are required for producing sterility, simulations show that one of these, twice the inverse of the relative size of the largest fertile fragment, provides good average approximations when as few as five fertile fragments are analyzed. The estimators have been used for deducing the number of factors from previous data on several pairs of species. A particular result contrasts with the authors' interpretations: instead of the high number of sterility factors suggested, only a few per autosome are estimated in both reciprocal crosses involving Drosophila buzzatii and D. koepferae. It has been possible to map these factors, between three and six per chromosome, in the autosomes 3 and 4 of these species. Out of 203 introgressions of different fragments or combinations of fragments, the outcome of at least 192 is explained by the mapped zones. These results suggest that autosome-mediated sterility in the male hybrids of these species is mediated by a few epistatic factors, similarly to X-mediated sterility in the hybrids of other Drosophila species.

Animals↗
PubMed2006

Methicillin-resistant Staphylococcus aureus sterile-site infection: The importance of appropriate initial antimicrobial treatment.

OBJECTIVE: The first goal of this investigation was to determine the rate of appropriate initial antimicrobial administration to patients with methicillin-resistant Staphylococcus aureus (MRSA) sterile-site infections. Our second goal was to evaluate the influence of appropriate initial treatment of MRSA sterile-site infection on outcome. DESIGN: A retrospective, single-center, observational cohort study. SETTING: Barnes-Jewish Hospital, a 1200-bed urban teaching facility. PATIENTS: Adult patients requiring hospitalization identified to have an MRSA sterile-site infection. INTERVENTIONS: Retrospective data collection from automated hospital and pharmacy databases. MEASUREMENTS AND MAIN RESULTS: Five hundred forty-nine patients with S. aureus sterile site infections were identified during a 3-yr period (January 2002 through December 2004). One hundred twenty-seven (23.1%) died during hospitalization. Hospital mortality was statistically greater for patients receiving inappropriate initial antimicrobial treatment (n = 380) within 24 hrs of a positive culture than for those receiving appropriate initial treatment (n = 169) (26.1% vs. 16.6%; p = .015). Multiple logistic regression analysis identified inappropriate initial antimicrobial treatment (adjusted odds ratio [AOR], 1.92; 95% confidence interval [CI], 1.48-2.50; p = .0134), vasopressor administration (AOR, 5.49; 95% CI, 4.08-7.38; p < .001), and increasing age (1-yr increments) (AOR, 1.03; 95% CI, 1.02-1.04; p < .001) as independent determinants of hospital mortality. CONCLUSIONS: Inappropriate initial antimicrobial treatment of MRSA sterile-site infections is common and is associated with an increased risk of hospital mortality. Appropriate antimicrobial treatment of MRSA sterile-site infections may be maximized by increased use of initial empirical antimicrobial treatment regimens targeting MRSA in patients at risk for this infection until organism identification and susceptibility become known.

Adolescent↗
PubMed1983

Studies on Genetic Male-Sterile Soybeans : II. Effect of Nodulation on Photosynthesis and Carbon Partitioning in Leaves.

Soybean (Glycine max L. Merr.) germplasm, essentially isogenic except for loci controlling male sterility (ms(1)) and nodulation (rj(1)), were developed to study the effects of reproductive development and nitrogen source on certain aspects of photosynthesis. Plants were sampled from flowering (77 days after transplanting) until maturity (150 days after transplanting). With all four genotypes, net carbon exchange rates were highest at flowering and declined thereafter. Photosynthetic rates of the sterile genotypes (nodulated and non-nodulated) declined more rapidly than the fertile genotypes, and after 105 days, both sterile genotypes maintained low but relatively constant carbon exchange rates (<3 milligrams CO(2)/gram fresh weight per hour). Photosynthetic rates and starch accumulation (difference between afternoon and morning levels) declined with time. The sterile genotypes attained the highest morning starch levels, which reflected reduced starch mobilization. After 92 days, the proportion of photosynthetically fixed carbon that was partitioning into starch (relative leaf starch accumulation) in the sterile genotypes increased dramatically. In contrast, relative leaf starch accumulation in the fertile genotypes remained relatively constant with time. Throughout the test period, all four genotypes maintained leaf sucrose levels between 5 and 15 micromoles glucose equivalents per gram fresh weight.The activities of sucrose phosphate synthase (SPS) in leaf extracts of the four genotypes declined from 77 to 147 days. Nodulated genotypes tended to maintain higher activities (leaf fresh weight basis) than did the non-nodulated genotypes. In general, relative leaf starch accumulation was correlated negatively with the activity of SPS (normalized with leaf net carbon exchange rate) in leaf extracts for all four genotypes during early reproductive development, and for the fertile genotypes at all sampling dates. In contrast, leaf sucrose content was correlated positively with SPS activity during early reproductive development. These results suggested that a direct relation existed between the activity of SPS and starch/sucrose levels in soybean leaves. However, the interaction between these processes also may be influenced by other factors, particularly when leaf photosynthetic rates and plant demand for assimilates is low, as in the sterile genotypes.

Journal Article↗
PubMed1992

Premature dissolution of the microsporocyte callose wall causes male sterility in transgenic tobacco.

Male sterility in a petunia cytoplasmic male sterile line has been attributed to the early appearance of active callase, a beta-1,3-glucanase, in the anther locule. This leads to premature dissolution of the callose walls surrounding the microsporogenous cells. We have mimicked this aspect of the petunia line in transgenic tobacco by engineering the secretion of a modified pathogenesis-related vacuolar beta-1,3-glucanase from the tapetum prior to the appearance of callase activity in the locule. Plants expressing the modified glucanase from tapetum-specific promoters exhibited reduced male fertility, ranging from complete to partial male sterility. Callose appearance and distribution are normal in the male sterile transgenic plants up to prophase I, whereupon callose is prematurely degraded. Meiosis and cell division occur normally. The resultant microspores have an abnormally thin cell wall that lacks sculpturing. The tapetum shows hypertrophy. Male sterility is probably caused by bursting of the aberrant microspores at a time corresponding to microspore release. These results demonstrate that premature callose degradation is sufficient to cause male sterility and suggest that callose is essential for the formation of a normal microspore cell wall.

Base Sequence↗
PubMed2001

Evidence for Dobzhansky-Muller incompatibilites contributing to the sterility of hybrids between Mimulus guttatus and M. nasutus.

Both chromosomal rearrangements and negative interactions among loci (Dobzhansky-Muller incompatibilities) have been advanced as the genetic mechanism underlying the sterility of interspecific hybrids. These alternatives invoke very different evolutionary histories during speciation and also predict different patterns of sterility in artificial hybrids. Chromosomal rearrangements require drift, inbreeding, or other special conditions for initial fixation and, because heterozygosity per se generates any problems with gamete formation, F1 hybrids will be most infertile. In contrast, Dobzhansky-Muller incompatibilities may arise as byproducts of adaptive evolution and often affect the segregating F2 generation most severely. To distinguish the effects of these two mechanisms early in divergence, we investigated the quantitative genetics of hybrid sterility in a line cross between two members of the Mimulus guttatus species complex (M. guttatus and M. nasutus). Hybrids showed partial male and female sterility, and the patterns of infertility were not consistent with the action of chromosomal rearrangements alone. F2 and F1 hybrids exhibited equal decreases in pollen viability (> 40%) relative to the highly fertile parental lines. A large excess of completely pollen-sterile F2 genotypes also pointed to the segregation of Dobzhansky-Muller incompatibility factors affecting male fertility. Female fertility showed a pattern similarly consistent with epistatic interactions: F2 hybrids produced far fewer seeds per flower than F1 hybrids (88.0 +/- 2.8 vs. 162.9 +/- 8.5 SE, respectively) and either parental line, and many F2 genotypes were completely female sterile. Dobzhansky-Muller interactions also resulted in the breakdown of several nonreproductive characters and appear to contribute to correlations between male and female fertility in the F2 generation. These results parallel and contrast with the genetics of postzygotic isolation in model animal systems and are a first step toward understanding the process of speciation in this well-studied group of flowering plants.

Asteraceae↗