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1.
J Dev Orig Health Dis ; 12(3): 420-427, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32513328

RESUMO

While fetal alcohol spectrum disorder (FASD) has primarily been thought of as a neurodevelopmental condition, research is beginning to highlight its 'whole-body' implications. Accordingly, the current study sought to provide a snapshot of potential health issues. Caregivers of children (median age of 12 years) with an FASD diagnosis were invited to participate in an online survey. Information relating to sample demographics, FASD status of the child and health outcomes were collected. The prevalence of health conditions reported in the FASD sample was compared against national prevalence data. Multiple linear regression utilising a stepwise approach was used to investigate potential predictors of the number of diagnosed health conditions. Survey data were from an international cohort (n = 197), with the majority of respondents based in Australia (40.2%) or the United States (27.7%). The most commonly reported diagnosed health conditions were eye conditions (44.7%), asthma (34.5%), heart conditions (34.0%) and skin conditions (27.4%). Binomial testing indicated the proportion of children diagnosed with these disorders was generally higher in the current FASD population, compared to national prevalence data. Indicators of metabolic dysfunction including diabetes and obesity were not significantly different compared to national prevalence data. Age of FASD diagnosis, existence of comorbid mental health conditions and the primary caregiver being in paid work were identified as being associated with the prevalence of diagnosed health conditions. Overall, the study has provided an up-to-date snapshot of health problems reported in a sample of children with FASD, confirming their increased risk of adverse health outcomes.


Assuntos
Transtornos do Espectro Alcoólico Fetal/epidemiologia , Adolescente , Adulto , Austrália/epidemiologia , Cuidadores , Criança , Pré-Escolar , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Inquéritos e Questionários , Adulto Jovem
2.
Surg Endosc ; 20(12): 1872-8, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17031746

RESUMO

BACKGROUND: Hepatobiliary iminodiacetic scan with ejection fraction (HIDA EF) is used to evaluate chronic acalculous cholecystitis (CAC). A presumed etiology of CAC is sphincter of Oddi hypertension (SOH). In this study, we evaluated the value of HIDA EF to predict patient response to laparoscopic cholecystectomy and to identify SOH. METHODS: A prospective study of 93 patients with biliary pain but without gallstones (CAC) who underwent preoperative HIDA EF was conducted. At laparoscopic cholecystectomy, transcystic antegrade biliary manometry was performed to determine the SO pressure. Patients were evaluated postoperatively for response to cholecystectomy. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. The outcomes were compared with the clinical impression. RESULTS: Of the 93 patients with both HIDA EF and SOP measurements, 50 had abnormal EF (< 35%); of these, 29 had SOH (SO pressure > or = 40 mmHg). Of the 43 patients with normal HIDA EF, 30 had SOH. The sensitivity was 49%, specificity 38%, PPV 58%, and NPV 30%. Eighty-six of the 93 patients returned for follow-up evaluation. Follow-up ranged from 0 to 99 months, with a mean of 26.4 months. Overall, 73 patients (85%) improved. Of the 46 with abnormal HIDA EF, 42 (91%) improved. Of the 40 patients with normal HIDA EF, 31 (77.5%) improved. The sensitivity was 57.7%, specificity 69.2%, PPV 91.3%, and NPV 22.5%. CONCLUSION: Although the PPV of abnormal HIDA EF is high, it is not much better than the clinical impression. The sensitivity and specificity are marginal. The NPV is poor. Based on the review of these 93 patients, HIDA EF is not reliable for identifying CAC. We recommend that patients with normal HIDA EF have additional testing or consultation before ruling out CAC. HIDA EF does not predict SOH.


Assuntos
Colecistite Acalculosa/diagnóstico , Colecistectomia Laparoscópica/métodos , Esvaziamento da Vesícula Biliar/fisiologia , Esfíncter da Ampola Hepatopancreática/fisiopatologia , Colecistite Acalculosa/fisiopatologia , Colecistite Acalculosa/cirurgia , Adolescente , Adulto , Idoso , Doença Crônica , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Pressão , Prognóstico , Estudos Prospectivos , Sensibilidade e Especificidade
3.
J Comp Neurol ; 416(3): 277-90, 2000 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-10602088

RESUMO

Mesenteric arteries of the rat are surrounded by a plexus of primary afferent nerve terminals which contain both substance P (SP) and calcitonin gene-related peptide (CGRP). The ultrastructural arrangement of the innervation was studied in second-order branches of the rat mesenteric artery using immunohistochemical labelling with antibodies against SP. The structure and distribution of SP-immunoreactive (SP+) and SP-negative (SP-, i.e., virtually all noradrenergic) axons and their terminals within the adventitia of the artery have been determined. Sixteen percent of axons and 22% of varicosities in the perivascular plexus were SP+. Most of the SP+ varicosities lay between 0.4 and 2 microm from the smooth muscle cells, whereas most SP- varicosities lay much closer to the vessel (i.e., <1 microm). SP+ varicosities typically contained the same number and size of small synaptic vesicles and mitochondria as SP- varicosities, but there were more large dense-cored vesicles in the SP+ varicosities. Unlike SP- varicosities, the peptidergic varicosities did not show clustering of synaptic vesicles toward one part of the axon membrane, and none of them formed junctions with the smooth muscle cells. Close relationships between SP+ and SP- varicosities lacked any detectable structural specialization. The arrangement of SP+ (primary afferent) terminals and their association with vascular smooth muscle cells indicates that peptide released from afferent terminals must diffuse further than noradrenaline from sympathetic terminals to reach the vascular smooth muscle.


Assuntos
Artérias Mesentéricas/inervação , Músculo Liso Vascular/inervação , Terminações Pré-Sinápticas/química , Terminações Pré-Sinápticas/ultraestrutura , Substância P/análise , Animais , Imunofluorescência , Imuno-Histoquímica , Mitocôndrias/ultraestrutura , Junção Neuromuscular/química , Junção Neuromuscular/ultraestrutura , Ratos , Ratos Wistar , Vesículas Sinápticas/química , Vesículas Sinápticas/ultraestrutura
4.
J Comp Neurol ; 361(4): 699-709, 1995 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-8576423

RESUMO

Most sympathetic postganglionic noradrenergic varicosities of the perivascular plexus of small muscular arteries in laboratory mammals make contact with the outer smooth muscle cells of the media at neuromuscular junctions. These neurovascular junctions have most of the characteristics of those in skeletal muscle. In the rat tail artery, which bears a particularly dense perivascular plexus, many studies indicate that both purinergic and noradrenergic mechanisms underlie neurally mediated vasoconstriction. We have examined the relationship of large axonal varicosities to the smooth muscle surface of proximal parts of this vessel using three-dimensional reconstructions from serial thin sections photographed in the electron microscope. Unlike in small arterioles, less than 50% of the large photographed in the electron microscope. Unlike in small arterioles, less than 50% of the large varicosities lying within 1 micron of the outer surface of this artery were found to make neuromuscular junctions. In some non-contacting varicosities, accumulations of synaptic vesicles were aggregated toward axonal membrane which was bare of Schwann cell toward the vessel surface. Prejunctional membrane specializations were detected at 20% of contacting and 12% of non-contacting varicosities. All of the latter lay close (< 350nm) to the smooth muscle. These anatomical data suggest that, in the rat tail artery, transmitter release by exocytosis may occur from both types of varicosity.


Assuntos
Artérias/anatomia & histologia , Junção Neuromuscular/anatomia & histologia , Cauda/irrigação sanguínea , Animais , Feminino , Microscopia Eletrônica , Músculo Liso Vascular/anatomia & histologia , Músculo Liso Vascular/ultraestrutura , Ratos , Sistema Nervoso Simpático/anatomia & histologia
5.
Obstet Gynecol ; 78(5 Pt 2): 972-4, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1923243

RESUMO

Vaginal fibromyomata are rare benign neoplasms; approximately 300 have been reported in the world literature. The clinical presentation is variable and the consistency of the mass on pelvic examination may be misleading. A mass may occur anywhere along the vaginal tube and is usually localized, mobile, nontender, and circumscribed. Its consistency, however, may range from solid to cystic. These lesions may be asymptomatic or may cause pain or urinary tract symptoms. Transabdominal and intravaginal sonography along with needle biopsy are valuable in making the preoperative diagnosis of a benign smooth-muscle tumor. Vaginal enucleation is the treatment of choice. Operative management should include evaluation of urethrovesical support and possible reconstruction, eg, pubourethral ligament plication.


Assuntos
Leiomioma/diagnóstico por imagem , Neoplasias Vaginais/diagnóstico por imagem , Adulto , Biópsia por Agulha , Feminino , Humanos , Leiomioma/patologia , Leiomioma/cirurgia , Pessoa de Meia-Idade , Ultrassonografia , Neoplasias Vaginais/patologia , Neoplasias Vaginais/cirurgia
6.
Obstet Gynecol ; 71(5): 736-8, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3357663

RESUMO

To determine whether intraumbilical oxytocin would shorten the third stage of labor, we enrolled 50 normal parturients into a randomized, double-blind protocol. Either 10 U of oxytocin diluted to 20 mL in normal saline (25 subjects) or 20 mL of normal saline alone (25 subjects) was injected into the placental circulation within one minute after cord clamping. The mean (+/- SD) duration of the third stage was 4.1 +/- 2.0 minutes in saline-treated subjects and 4.6 +/- 3.4 minutes in those treated with oxytocin. Intraumbilical oxytocin was not effective in shortening the normal third stage of labor.


Assuntos
Terceira Fase do Trabalho de Parto/efeitos dos fármacos , Trabalho de Parto/efeitos dos fármacos , Ocitocina/farmacologia , Adulto , Método Duplo-Cego , Feminino , Humanos , Injeções Intravenosas , Ocitocina/administração & dosagem , Gravidez , Distribuição Aleatória , Veias Umbilicais
7.
Obstet Gynecol ; 88(4 Pt 2): 706-8, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8841261

RESUMO

BACKGROUND: Non-Hodgkin lymphomas, a common AIDS-defining manifestation of human immunodeficiency virus (HIV), are aggressive, advanced at diagnosis, and tend to involve extranodal sites. Burkitt lymphoma comprises approximately 20% of AIDS-related non-Hodgkin lymphomas. Sites frequently affected by the disease include the central nervous system, bone marrow, gastrointestinal tract, and mucocutaneous tissue. Gonadal involvement is less common; reports of testicular lymphomas in adult males with AIDS have been sporadic. Ovarian involvement in AIDS-related lymphoma is exceedingly rare and usually involves pediatric patients. CASE: We report an unusual case in which disseminated Burkitt lymphoma presented as pelvic pain in a 32-year-old woman with AIDS. At laparoscopy, the ovaries were unremarkable in appearance but at the upper limits of normal size. However, extreme friability of the left ovary led to hemorrhage and oophorectomy. Pathologic evaluation of the ovary resulted in the diagnosis of Burkitt lymphoma. CONCLUSION: With improved survival because of antiretroviral therapy, the incidence of AIDS-related lymphomas is expected to rise. Lymphoma should be considered in the differential diagnosis of women with AIDS with perplexing abdominal or pelvic symptoms.


Assuntos
Linfoma de Burkitt/diagnóstico , Linfoma Relacionado a AIDS/diagnóstico , Neoplasias Ovarianas/diagnóstico , Dor Pélvica/etiologia , Adulto , Linfoma de Burkitt/complicações , Feminino , Humanos , Linfoma Relacionado a AIDS/complicações , Neoplasias Ovarianas/complicações
8.
Magn Reson Imaging ; 9(6): 955-7, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1766322

RESUMO

We present a case report of a urethral diverticulum where magnetic resonance imaging suggested infected contents of the urethral diverticulum besides providing superb detail of periurethral anatomy. The critical clinical question was answered.


Assuntos
Divertículo/diagnóstico , Doenças Uretrais/diagnóstico , Adulto , Feminino , Humanos , Infecções/diagnóstico , Imageamento por Ressonância Magnética , Uretra/patologia
9.
Magn Reson Imaging ; 12(4): 569-76, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8057761

RESUMO

MRI is a modality that provides excellent anatomic detail, especially of soft tissue and bone. Comparison of T1-weighted and T2-weighted images offers significant diagnostic information of pelvic pathology. In five problematic gynecologic cases, magnetic resonance imaging (MRI) provided key information for optimal treatment planning or a definitive diagnosis for the gynecologist.


Assuntos
Doenças dos Genitais Femininos/diagnóstico , Imageamento por Ressonância Magnética , Adulto , Feminino , Genitália Feminina/patologia , Humanos , Pessoa de Meia-Idade
10.
Obstet Gynecol Clin North Am ; 21(2): 357-79, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7936549

RESUMO

This article provides a logical approach to the evaluation and management of urinary incontinence in the perimenopausal and postmenopausal woman. The impact of the climacteric on normal anatomy and physiology of the female continence mechanism is addressed. Primary office evaluation and guidelines for referrals are provided. The surgical and nonsurgical treatments of incontinence are discussed with illustrative cases.


Assuntos
Climatério , Incontinência Urinária , Climatério/fisiologia , Feminino , Humanos , Exame Físico , Pós-Menopausa , Pré-Menopausa , Urinálise , Incontinência Urinária/diagnóstico , Incontinência Urinária/fisiopatologia , Incontinência Urinária/terapia , Urodinâmica
11.
J Reprod Med ; 40(11): 809-12, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8592319

RESUMO

BACKGROUND: In the last 20 years the technique of operative laparoscopy has rapidly evolved, so the majority of gynecologic procedures can now be performed endoscopically. However, laparoscopy is still a relatively new technique, and we have much to learn about its associated complications and their management. In the English-language literature there are 15 reported cases of bladder perforation associated with laparoscopy, and 4 of them occurred with insertion of the primary trocar. CASES: Two cases are described in which incidental cystotomy occurred with primary trocar insertion during laparoscopy for infertility and chronic pelvic pain. Both patients were treated successfully with Foley catheterization. CONCLUSION: To our knowledge, nothing was written earlier about conservative management of incidental cystotomy occurring at the time of primary laparoscopic trocar insertion. This paper reports two such cases.


Assuntos
Laparoscopia/efeitos adversos , Dor Pélvica/cirurgia , Bexiga Urinária/lesões , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Punções
12.
J Reprod Med ; 39(5): 408-10, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8064709

RESUMO

We report hematometra as a rare complication of cervical stenosis after a cone biopsy. Ultrasound and magnetic resonance imaging were very helpful in determining the diagnosis in conjunction with a physical examination.


Assuntos
Biópsia/efeitos adversos , Hematometra/diagnóstico , Hematometra/etiologia , Doenças do Colo do Útero/diagnóstico , Doenças do Colo do Útero/etiologia , Displasia do Colo do Útero/patologia , Adulto , Constrição Patológica , Feminino , Hematometra/cirurgia , Humanos , Histerectomia , Imageamento por Ressonância Magnética , Doenças do Colo do Útero/cirurgia
13.
Chin J Physiol ; 32(1): 1-12, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2638615

RESUMO

The purpose of the present study was to examine the afferent mechanisms for phasic hypoglossal and phrenic responses to airflow changes in the upper airway (UAW). An isolated UAW was produced in decerebrate, unanesthetized, vagotomized, paralyzed and ventilated cats. Activities of both the hypoglossal and phrenic nerves were monitored at hyperoxic (FETCO2 greater than 0.80) normocapnia (FETCO2 = 0.04-0.05). As inspiratory airflow passing through the UAW, hypoglossal activity enhanced significantly while phrenic discharge reduced (p less than 0.01). After bilateral denervation of the superior laryngeal nerve (SLN), enhancements of hypoglossal activity in response to the same level of airflow were much lower whereas reduce in phrenic discharge was eliminated. Combined with sectioning of the glossopharyngeal nerve (GPN), augmentation of hypoglossal response to airflow was even higher. This increase in hypoglossal activity with airflow changes was not discerned when the trigeminal ganglion (TGG) was further destroyed. These results suggest that airflow changes in the UAW, which was sensed by the receptors in the SLN, GPN, and TGG, produce an increase in hypoglossal discharge and a decrease in phrenic burst. Increase in hypoglossal activity in response to airflow change in the UAW may relate to keeping a patent UAW.


Assuntos
Nervo Hipoglosso/fisiologia , Nervo Frênico/fisiologia , Sistema Respiratório/inervação , Vias Aferentes/fisiologia , Animais , Gatos , Estado de Descerebração , Denervação , Feminino , Masculino , Respiração/fisiologia , Fenômenos Fisiológicos Respiratórios
14.
Transplant Proc ; 46(6): 1867-71, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25131056

RESUMO

BACKGROUND: Liver regeneration has great importance for transplantation, especially in children; however, it has not been studied sufficiently in development animals. Ischemia-reperfusion injury is a problem, and strategies such as ischemic preconditioning and postconditioning are not well defined regarding regeneration. OBJECTIVE: This study sought to evaluate liver regeneration with modulation by ischemic preconditioning and postconditioning in prepubertal rats subjected to total ischemia and reperfusion. METHODS: Thirty-five 5-week-old female Wistar rats were divided into groups of 7 animals each: control group (SHAM), 70% hepatectomy (HEP), total ischemia 30 minutes before hepatectomy (IR), ischemic preconditioning 10/10 minutes before ischemia (PRE), and two 30/30-second ischemic postconditioning cycles after ischemia and hepatectomy (POS). All animals were subjected to 24-hour reperfusion. Aspartate aminotransferase and alanine aminotransferase activity were measured to evaluate liver damage, and histological analysis, proliferating cell nuclear antigen (PCNA) and regenerated mass liver were used to evaluate liver regeneration. Statistical analyses were performed using ANOVA and Kruskal-Wallis test. RESULTS: Alanine aminotransferase and aspartate aminotransferase levels were significantly lower in conditioned groups than in the IR group. Regarding mitotic index, IR > control group and HEP (P < .05), PRE and POS were not significantly different from IR, and POS > HEP (P < .05). PCNA analysis showed that IR > HEP (P < .01), PRE < IR (P < .01), and no significant differences were observed between POS and IR groups. No significant differences in regenerated mass liver were observed between conditioned groups and HEP. CONCLUSIONS: Ischemic postconditioning prevented ischemic injury, promoted greater liver regeneration, and should be further investigated as an alternative better than ischemic preconditioning.


Assuntos
Pós-Condicionamento Isquêmico/métodos , Precondicionamento Isquêmico/métodos , Hepatopatias/cirurgia , Regeneração Hepática , Traumatismo por Reperfusão/prevenção & controle , Animais , Modelos Animais de Doenças , Feminino , Hepatectomia , Hepatopatias/patologia , Ratos , Ratos Wistar
16.
J Pediatr Oncol Nurs ; 7(1): 9-13, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2363871

RESUMO

Vincristine is a highly effective cell-cycle specific chemotherapeutic agent used in the treatment of most pediatric malignancies. The major dose-limiting side effect of this drug is neurotoxicity, which can present in the form of peripheral, autonomic, or cranial nerve deficits. Conditions such as liver dysfunction can increase the risk for vincristine neurotoxicity. The only treatment for severe toxicity is to decrease the drug dose or to discontinue the drug. Many of the symptoms of neurotoxicity are subjective and therefore adequate assessment is often difficult. Baseline data is obtained before starting vincristine and with each subsequent clinic visit so that the appropriate drug dose can be determined to maximize tumor response with the fewest side effects. Nursing interventions are directed at symptom management. Patient-family education centers on relating informing of the potential and symptoms of neurotoxicity, with an emphasis on safety precautions.


Assuntos
Neoplasias/enfermagem , Doenças do Sistema Nervoso/induzido quimicamente , Vincristina/efeitos adversos , Criança , Humanos , Neoplasias/tratamento farmacológico , Doenças do Sistema Nervoso/fisiopatologia , Avaliação em Enfermagem , Vincristina/uso terapêutico
17.
Occup Ther Health Care ; 4(2): 37-46, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-23947502

RESUMO

A movement program for children based on sensory integration theory, using movement education concepts, was developed by an occupational therapist for use in preschool settings. The goal of the program is to enhance normal growth and development in 3-5 year old children, and to provide a vehicle for early identification of children with developmental delays. The paper will describe the curriculum and provide examples of activities used as well as suggestions for instituting such a program elsewhere. Research has not been conducted on the effects of the program, but comments from teachers, parents and therapists involved indicate that the program is meeting its goals.

18.
J Appl Microbiol ; 96(2): 289-301, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14723690

RESUMO

AIMS: To determine the mechanisms of Bacillus subtilis spore killing by and resistance to the general biological decontamination agents, Decon and Oxone. METHODS AND RESULTS: Spores of B. subtilis treated with Decon or Oxone did not accumulate DNA damage and were not mutagenized. Spore killing by these agents was increased if spores were decoated. Spores prepared at higher temperatures were more resistant to these agents, consistent with a major role for spore coats in this resistance. Neither Decon nor Oxone released the spore core's depot of dipicolinic acid (DPA), but Decon- and Oxone-treated spores more readily released DPA upon a subsequent normally sublethal heat treatment. Decon- and Oxone-killed spores initiated germination with dodecylamine more rapidly than untreated spores, but could not complete germination triggered by nutrients or Ca(2+)-DPA and did not degrade their peptidoglycan cortex. However, lysozyme treatment did not recover these spores. CONCLUSIONS: Decon and Oxone do not kill B. subtilis spores by DNA damage, and a major factor in spore resistance to these agents is the spore coat. Spore killing by both agents renders spores defective in germination, possibly because of damage to the inner membrane of spore. SIGNIFICANCE AND IMPACT OF STUDY: These results provide information on the mechanisms of the killing of bacterial spores by Decon and Oxone.


Assuntos
Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Álcoois Graxos/farmacologia , Peróxido de Hidrogênio/farmacologia , Ácidos Sulfúricos/farmacologia , Aminas/farmacologia , Membrana Celular/efeitos dos fármacos , Dano ao DNA , DNA Bacteriano/análise , Descontaminação , Farmacorresistência Bacteriana , Inibidores Enzimáticos/análise , Temperatura Alta , Mutagênese/fisiologia , Ácidos Picolínicos/análise , Esporos Bacterianos/efeitos dos fármacos , Tensoativos/farmacologia
19.
J Appl Microbiol ; 95(1): 54-67, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12807454

RESUMO

AIMS: To determine the mechanisms of Bacillus subtilis spore killing by hypochlorite and chlorine dioxide, and its resistance against them. METHODS AND RESULTS: Spores of B. subtilis treated with hypochlorite or chlorine dioxide did not accumulate damage to their DNA, as spores with or without the two major DNA protective alpha/beta-type small, acid soluble spore proteins exhibited similar sensitivity to these chemicals; these agents also did not cause spore mutagenesis and their efficacy in spore killing was not increased by the absence of a major DNA repair pathway. Spore killing by these two chemicals was greatly increased if spores were first chemically decoated or if spores carried a mutation in a gene encoding a protein essential for assembly of many spore coat proteins. Spores prepared at a higher temperature were also much more resistant to these agents. Neither hypochlorite nor chlorine dioxide treatment caused release of the spore core's large depot of dipicolinic acid (DPA), but hypochlorite- and chlorine dioxide-treated spores much more readily released DPA upon a subsequent normally sub-lethal heat treatment than did untreated spores. Hypochlorite-killed spores could not initiate the germination process with either nutrients or a 1 : 1 chelate of Ca2+-DPA, and these spores could not be recovered by lysozyme treatment. Chlorine dioxide-treated spores also did not germinate with Ca2+-DPA and could not be recovered by lysozyme treatment, but did germinate with nutrients. However, while germinated chlorine dioxide-killed spores released DPA and degraded their peptidoglycan cortex, they did not initiate metabolism and many of these germinated spores were dead as determined by a viability stain that discriminates live cells from dead ones on the basis of their permeability properties. CONCLUSIONS: Hypochlorite and chlorine dioxide do not kill B. subtilis spores by DNA damage, and a major factor in spore resistance to these agents appears to be the spore coat. Spore killing by hypochlorite appears to render spores defective in germination, possibly because of severe damage to the spore's inner membrane. While chlorine dioxide-killed spores can undergo the initial steps in spore germination, these germinated spores can go no further in this process probably because of some type of membrane damage. SIGNIFICANCE AND IMPACT OF THE STUDY: These results provide information on the mechanisms of the killing of bacterial spores by hypochlorite and chlorine dioxide.


Assuntos
Bacillus subtilis/efeitos dos fármacos , Compostos Clorados/farmacologia , Desinfetantes/farmacologia , Ácido Hipocloroso/farmacologia , Oxidantes/farmacologia , Óxidos/farmacologia , Bacillus subtilis/genética , Dano ao DNA/efeitos dos fármacos , DNA Bacteriano/efeitos dos fármacos , Farmacorresistência Bacteriana , Inibidores Enzimáticos/análise , Genes Bacterianos/genética , Mutação/genética , Ácidos Picolínicos/análise , Esporos Bacterianos/efeitos dos fármacos
20.
J Appl Microbiol ; 96(5): 1133-42, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15078531

RESUMO

AIMS: To determine the mechanisms of Bacillus subtilis spore killing by and resistance to aqueous ozone. METHODS AND RESULTS: Killing of B. subtilis spores by aqueous ozone was not due to damage to the spore's DNA, as wild-type spores were not mutagenized by ozone and wild-type and recA spores exhibited very similar ozone sensitivity. Spores (termed alpha-beta-) lacking the two major DNA protective alpha/beta-type small, acid-soluble spore proteins exhibited decreased ozone resistance but were also not mutagenized by ozone, and alpha-beta- and alpha-beta-recA spores exhibited identical ozone sensitivity. Killing of spores by ozone was greatly increased if spores were chemically decoated or carried a mutation in a gene encoding a protein essential for assembly of the spore coat. Ozone killing did not cause release of the spore core's large depot of dipicolinic acid (DPA), but these killed spores released all of their DPA after a subsequent normally sublethal heat treatment and also released DPA much more readily when germinated in dodecylamine than did untreated spores. However, ozone-killed spores did not germinate with either nutrients or Ca(2+)-DPA and could not be recovered by lysozyme treatment. CONCLUSIONS: Ozone does not kill spores by DNA damage, and the major factor in spore resistance to this agent appears to be the spore coat. Spore killing by ozone seems to render the spores defective in germination, perhaps because of damage to the spore's inner membrane. SIGNIFICANCE AND IMPACT OF THE STUDY: These results provide information on the mechanisms of spore killing by and resistance to ozone.


Assuntos
Bacillus subtilis/efeitos dos fármacos , Oxidantes Fotoquímicos/farmacologia , Ozônio/farmacologia , Aminas/metabolismo , Bacillus subtilis/fisiologia , Proteínas de Bactérias/metabolismo , Dano ao DNA/efeitos dos fármacos , DNA Bacteriano/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Farmacorresistência Bacteriana/fisiologia , Inibidores Enzimáticos/metabolismo , Mutagênese/efeitos dos fármacos , Ácidos Picolínicos/metabolismo , Esporos Bacterianos/efeitos dos fármacos , Tensoativos/metabolismo
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