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1.
Vet J ; 298-299: 106013, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37355009

RESUMO

Osteomalacia outbreaks often occur in cattle grazing native pastures in regions with endemic phosphorous (P) deficiency. This study evaluated the responses of two groups of cows, initially with clinical signs of chronic P deficiency, to P supplements (100 g P/kg) offered ad libitum for 13 weeks as a loose mineral mix (LMM group) or the same mineral mix offered as blocks (BMM group). Half of the cows in each group were categorized as 'with' or 'without' severe osteopenia according to a test that depended on the resistance to penetration of a needle through the left lateral process of the L4-L5 lumbar vertebra. The groups grazed two paddocks that were switched each 3 weeks. The liveweight, supplement intakes, and the P-concentrations in soil, forage, blood, and external cortical bone (ECB) of the ribs were measured. The bicarbonate-extractable P in soil was 3.5 mg/kg. The mean of total P in forage (0.95 g/kg/DM), inorganic P in serum (iP, 0.96 mmol/L), and total P in the ECB of the ribs (85 mg/mL) at the beginning of the experiment were all low and consistent with severe chronic P deficiency. The P supplementation allowed clinical recovery in 18/20 cows with their serum and ECB P and calcium approaching normal values and in the two remaining cows the only sign was abnormal gait. Cows consumed more of the LMM than BMM supplement (means 8.3 and 6.6 g P/day, respectively). After 13 weeks cows initially classified as 'with severe osteopenia' and supplemented with LMM had higher (P < 0.05) final liveweight (difference = 21.6 kg), iP (difference = 0.74 mmol/L), bone Ca (difference = 65.7 mg/mL) and bone P (difference = 26.5 mg/mL) concentrations and lower (P < 0.01) final serum Ca/iP ratio (difference = -0.65) than cows with severe osteopenia but supplemented with BMM. The treatment of severe P deficiency cows grazing P deficient sub-tropical grasslands by P supplementation for 13 weeks was more effective with LMM than BMM.


Assuntos
Doenças dos Bovinos , Osteomalacia , Feminino , Bovinos , Animais , Fósforo , Osteomalacia/veterinária , Ração Animal/análise , Suplementos Nutricionais , Minerais , Solo , Doenças dos Bovinos/tratamento farmacológico
2.
Braz J Microbiol ; 54(1): 475-490, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36602750

RESUMO

Salmonella enterica is a major food-borne pathogen that affects cattle-rearing systems worldwide. Little information is available on the epidemiology and pathology of salmonellosis and the virulence genes (VGs) carried by Salmonella in spontaneous outbreaks in cattle. We describe epidemiological findings in 15 fatal outbreaks of salmonellosis in Uruguayan dairy farms and the age, clinical signs, and pathology in 20 affected calves. We also describe the serotypes and frequencies of 17 VGs in the causative Salmonella strains and explore their associations with epidemiological, clinical, and pathological findings. Salmonella Typhimurium and Dublin were identified in 11/15 and 4/15 outbreaks, respectively. The most frequent reason for consultation was digestive disease (8 outbreaks caused by S. Typhimurium), followed by sudden death (4 outbreaks, 3 caused by S. Dublin). Morbidity, mortality, and lethality ranged 4.8-100%, 3.8-78.9%, and 10-100%, without significant differences between serotypes. Diarrhea, the most common clinical sign (14 cases), was associated with the Typhimurium serotype (OR = 26.95), especially in ≤ 30-day-old calves with fibrinous enteritis as the main autopsy finding. The Dublin serotype affected ≥ 50-day-old calves and was associated with fibrinosuppurative splenitis (p = 0.01) and tubulointerstitial nephritis (OR = 48.95). The chances of the Dublin serotype increased significantly with age. There was low variability of VG across serotypes. The pefA gene was associated with the Typhimurium serotype (OR = 21.95), macroscopic enteritis (p = 0.03), and microscopic fibrinosuppurative splenitis (p = 0.04). Understanding the epidemiology, pathology, and virulence of S. enterica at the farm level is key to delineating prevention and control strategies to mitigate its impact on animal and human health.


Assuntos
Doenças dos Bovinos , Intoxicação Alimentar por Salmonella , Salmonelose Animal , Salmonella enterica , Humanos , Animais , Bovinos , Salmonella typhimurium , Virulência , Salmonelose Animal/microbiologia , Doenças dos Bovinos/microbiologia , Surtos de Doenças
4.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1561-1565, July-Aug. 2020. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1131518

RESUMO

Calcinose enzoótica, causada por Nierembergia rivularis, no Uruguai, e Nierembergia veitchii, no Brasil, é uma doença caracterizada por mineralização de tecidos moles, hiperplasia das células parafoliculares da tireoide e elevação nos níveis de cálcio e fósforo. Descreve-se um caso de hiperplasia e carcinoma de células parafoliculares bilateral em um ovino de quatro anos, com calcinose enzoótica associada à intoxicação por Nierembergia rivularis. O diagnóstico histológico de hiperplasia e carcinoma de células parafoliculares é suportado pelas marcações imuno-histoquímicas positivas para calcitonina, peptídeo relacionado ao gene da calcitonina e enolase neurônio específica. Como a hiperplasia de células parafoliculares é uma lesão pré-neoplásica induzida por hipercalcemia, sugere-se que a hipercalcemia crônica causada pela intoxicação por N. rivularis pode ter induzido hiperplasia de células parafoliculares seguida de transformação em carcinoma, neste caso. Os efeitos carcinogênicos das plantas calcinogênicas no sistema endócrino devem ser melhor explorados.(AU)


Assuntos
Animais , Intoxicação por Plantas/veterinária , Calcinose/veterinária , Ovinos , Neoplasias da Glândula Tireoide/veterinária , Células Epiteliais da Tireoide/patologia , Plantas Tóxicas
5.
Braz J Microbiol ; 50(4): 1139-1144, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31606855

RESUMO

Salmonella enterica is an important animal and human pathogen that can cause enteritis and septicaemia in calves. Generally, antibiotics are prescribed for the treatment of salmonellosis in dairy calves. Here, we report the isolation of antibiotic resistant S. enterica serotypes from calves, including multidrug-resistant isolates. A total of 544 faecal samples from live healthy and diarrheic dairy calves from 29 commercial dairy farms and organ samples from 19 deceased calves that succumbed to salmonellosis in 12 commercial dairy farms in Uruguay were processed for selective S. enterica culture. In total, 41 isolates were serotyped, and susceptibility to 14 antibiotics, from 9 classes of compounds, was evaluated by disk-diffusion test. The minimum inhibitory concentration (MIC) was determined by microdilution. Salmonella Typhimurium was the most frequent serotype, followed by S. Dublin and S. Anatum. Whether determined by diffusion assay or microdilution, resistance to tetracycline, streptomycin and ampicillin were the most frequently pattern found. Based on MIC, 5 isolates were resistant to at least one antibiotic, 21 were resistant to 2 antibiotics, and 14 were multidrug-resistant (resistant to at least one antibiotic in 3 different categories of antibiotics). Eleven different resistance patterns were found. Multidrug resistance in S. enterica is a concern for animal and public health not only because of its zoonotic potential but also due to the possibility of transfer resistance determinants to other bacterial genera. This represents the first report of the antibiotic resistance in S. enterica in dairy farms in Uruguay.


Assuntos
Farmacorresistência Bacteriana Múltipla , Salmonelose Animal/microbiologia , Salmonella enterica/isolamento & purificação , Animais , Antibacterianos/farmacologia , Bovinos , Indústria de Laticínios , Fezes/microbiologia , Testes de Sensibilidade Microbiana , Salmonella enterica/efeitos dos fármacos , Uruguai
6.
J Comp Pathol ; 164: 32-36, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30360910

RESUMO

Salmonellosis is an enteric or multisystemic disease of global distribution that affects numerous animal species. Although Salmonella enterica has been associated with urinary tract lesions in man, information on urocystitis/ureteritis in cattle caused by salmonellae is lacking. This communication describes lesions of the inferior urinary tract in four Holstein calves with septicaemia caused by S. enterica subsp. enterica serotype Dublin. Examination of the urinary bladder revealed either diffuse irregular thickening (three cases) or petechiation (one case) of the mucosa. On histopathological examination, urocystitis with submucosal histiocytic, lymphocytic and plasmacytic infiltration and neutrophil transmigration through the urothelium was noted in all cases. In one case, a fibrinosuppurative ureteritis was detected. Salmonella Dublin was identified by culture, 16S rDNA sequencing and serotyping and Salmonella antigen was detected intralesionally by immunohistochemistry. Other lesions, indicative of septicaemia included hepatitis, enteritis, pericarditis, splenitis, lymphadenitis and pneumonia. We conclude that S. Dublin can be uropathogenic in cattle with septicaemia.


Assuntos
Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/patologia , Salmonelose Animal/patologia , Sepse/veterinária , Infecções Urinárias/veterinária , Animais , Bovinos , Salmonella enterica
7.
J Appl Microbiol ; 124(3): 922-929, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29316065

RESUMO

AIM: To analyse group A rotavirus (RVA) environmental contamination in waters used for calves' consumption and to assess viral viability in dairy farm water sources. METHODS AND RESULTS: We analysed 202 samples of water used for calves' consumption and RVA was detected by RT-qPCR in 35·1% (95% CI: 28·9-42·0%). A marked pattern of seasonality was observed with higher frequency of detection in colder than warmer months (P = 0·002). There was no association between viral load and season or between the number of milking cows in the herd and the detection of RVA in the farm. The viability of the RVA particles detected was confirmed by isolation of RVA in cell culture from 5 of 10 water samples. Furthermore, an RVA waterborne outbreak of neonatal calf diarrhoea was described. CONCLUSIONS: We demonstrate that RVA is frequent in dairy farm waters, and that the virus is infectious and capable of generating a diarrhoea outbreak. SIGNIFICANCE AND IMPACT OF THE STUDY: Neonatal diarrhoea syndrome leads to economic losses to the livestock industry worldwide. To determine transmission routes is essential to take action in this regard and reduce the impact that this syndrome has for the livestock production. The results obtained in this work alert the dairy industry and highlight that mitigation strategies are crucial to improve the microbiological quality of this water.


Assuntos
Doenças dos Bovinos/virologia , Água Doce/virologia , Infecções por Rotavirus/veterinária , Rotavirus/isolamento & purificação , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Diarreia/epidemiologia , Diarreia/veterinária , Diarreia/virologia , Fazendas , Fezes/virologia , Feminino , Masculino , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Rotavirus/classificação , Rotavirus/genética , Rotavirus/crescimento & desenvolvimento , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Poluição da Água
8.
Rofo ; 186(2): 151-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23975878

RESUMO

OBJECTIVES: The aim of the study was to determine whether automated quantification of pulmonary perfused blood volume (PBV) in dual-energy computed tomography pulmonary angiography (DE-CTPA) can be used to assess the severity of chronic thromboembolic pulmonary hypertension (CTEPH). METHODS: Automated quantification of PBV was performed in 25 consecutive CTEPH patients undergoing DE-CTPA. PBV values were correlated with cardiac index and pulmonary vascular resistance quantified by right heart catheterization and walking distance in the 6-minute walk test using Pearson's correlation coefficient and multivariate linear regression analysis to control for age and gender. RESULTS: DE-CTPA derived PBV values inversely correlated with systolic (r = -0.64, p = 0.001) and mean (r = -0.57, p = 0.004) pulmonary arterial pressure. There was a trend for PBV values to inversely correlate with pulmonary vascular resistance (r = -0.20, p = 0.35). No significant correlation was found between PBV values and cardiac index or 6-minute walking distance. These correlations were confirmed to be independent of age and gender on multivariate linear regression analysis. CONCLUSION: DE-CTPA can be used for an automated quantification of pulmonary PBV in chronic thromboembolic pulmonary hypertension. PBV values correlate inversely with systolic and mean pulmonary arterial pressure and can thus be used to estimate the severity of pulmonary hypertension in these patients. Citation Format: • Meinel FG, Graef A, Thierfelder KM et al. Automated Quantification of Pulmonary Perfused Blood Volume by Dual-Energy CTPA in Chronic Thromboembolic Pulmonary Hypertension. Fortschr Röntgenstr 2014; 186: 151 - 156.


Assuntos
Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/fisiopatologia , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/fisiopatologia , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Angiografia , Volume Sanguíneo , Determinação do Volume Sanguíneo/métodos , Doença Crônica , Feminino , Humanos , Hipertensão Pulmonar/etiologia , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/complicações , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
HNO ; 59(5): 437-46, 2011 May.
Artigo em Alemão | MEDLINE | ID: mdl-21505923

RESUMO

Cochlear implantation (CI) is a new form of treatment in the rehabilitation of single-sided deafness. The patient requires thorough initial examination and a full explanation of alternative treatment options prior to determining the indication for CI treatment. To date, we have treated 28 patients with CI, of whom data are available for 11 after 12 months. We examined speech comprehension in background noise and localisation ability 12 months after CI implantation compared to conventional CROS (contralateral routing of signal) hearing aids, BAHA (bone-anchored hearing aid) and hearing in untreated patients. In addition, we determined the subjective handicap (HHIE, hearing handicap inventory for the elderly) and the subjective success (IOI-HA, international outcome inventory for hearing aids; SSQ, spatial and qualities of hearing scale) of each treatment option. After 12 months' experience, the results show a significantly better localisation ability and an improvement in speech comprehension in background noise with CI than with the other treatment options. Subjective results also show a clear benefit with CI. Careful patient selection is a decisive factor for successful treatment of this patient group. Under these conditions, CI is a treatment option with which significant improvement in speech comprehension and localization ability in single-sided deafness is possible.


Assuntos
Implante Coclear/métodos , Implantes Cocleares , Perda Auditiva Unilateral/diagnóstico , Perda Auditiva Unilateral/terapia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
11.
HNO ; 59(5): 448-52, 2011 May.
Artigo em Alemão | MEDLINE | ID: mdl-21505922

RESUMO

The aim of our study was to evaluate results of insertion following cochlear implantation with Contour™ and Contour Advance™ electrode arrays in adult patients and to analyze individual insertion results for three experienced surgeons. We performed a retrospective analysis of postoperative 3D volume tomography results in 223 adult patients. The intracochlear electrode position was evaluated to be in scala tympani, scala vestibuli or with a dislocation from one scala to the other. Surgical methods were analyzed and assigned to the different surgeons. We observed a significant increase for scala tympani insertions from initially 33% to 84% and a reduction in dislocations from scala tympani to scala vestibuli from 71% with the Contour™ electrode to 22% with the Contour Advance™ electrode. Results for the different surgeons varied individually with regard to scala tympani insertion rates and dislocation rates over time. 3D Volume tomography offers an important method for postoperative quality control following cochlear implant surgery. The intracochlear electrode position could be determined in all cases. We were able to identify individual learning curves for insertion results. Controlling the insertion quality serves as a feedback of surgical results and may be helpful for improving surgical quality and thus rehabilitation results.


Assuntos
Implante Coclear/estatística & dados numéricos , Implantes Cocleares/estatística & dados numéricos , Perda Auditiva/epidemiologia , Perda Auditiva/reabilitação , Competência Profissional/estatística & dados numéricos , Adulto , Feminino , Alemanha/epidemiologia , Humanos , Resultado do Tratamento
12.
HNO ; 59(5): 461-4, 2011 May.
Artigo em Alemão | MEDLINE | ID: mdl-21505929

RESUMO

Cochlear implantation has become the standard procedure for the treatment of severe to profound hearing loss, even in patients with underlying diseases. We report the case of a CI patient who underwent cardiac defibrillation, following which he reported a reduction in sound quality, a worsening of tinnitus, as well as headaches. An integrity test showed multiple electrode anomalies which could not be directly attributed to the cardioversion. We performed explantation and reimplantation of the CI. During the course of rehabilitation, the patient showed good results in speech comprehension. Since cardioversion, like any electrical monopolar treatment, may damage CI, it should be avoided in CI patients wherever possible. If it cannot be avoided, we strongly recommend removing the sound processor during treatment sessions. When device-related problems occur, the treatment of choice is reimplantation.


Assuntos
Implantes Cocleares , Cardioversão Elétrica , Falha de Equipamento , Humanos , Masculino , Pessoa de Meia-Idade
14.
HNO ; 57(7): 657-62, 2009 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-19517077

RESUMO

The treatment of deaf and hearing-impaired children with cochlear implants has been established for several years. Nonetheless, no long-term results exist for studies of a representatively large number of children in the German-speaking area. These are necessary in order to formulate prognoses regarding the development and results of children undergoing implantation at various ages. In a retrospective study, we assessed the data of 156 children with various implantation ages and a minimum follow-up period of 5 years for whom speech and audiological data (Oldenburg Sentence Test, Freiburg words/numbers test) were available. Our findings confirm the assumption that early-implanted children (<2 years) achieve the best speech-comprehension results. For this reason, support for a sufficient universal neonate hearing screen should be emphatically given so that implantation, after a hearing test phase, can be targeted in the first year of life. The surgical, anesthesiological, and rehabilitation conditions must be fulfilled, and surgical experience is required for operation on infants and small children.


Assuntos
Implante Coclear/métodos , Implantes Cocleares , Surdez/reabilitação , Recuperação de Função Fisiológica , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Estudos Retrospectivos , Resultado do Tratamento
15.
HNO ; 57(6): 533-41, 2009 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-19452138

RESUMO

The radiologic evaluation of the temporal bone in cochlear implant candidates can detect malformations of the inner ear in up to 20% of cases. The aim of our study was to analyze and classify malformations of the inner ear in patients with cochlear implants carried out from 2001 to 2009. Malformations of the inner ear, including malformations of the internal auditory canal were detected in 12.7% of children and 3.4% of adults. Mondini dysplasia was most common and occurred in 45% of cases. The surgical procedure had to be adapted according to the individual malformation. Modification of surgical access, management of intraoperative CSF gusher, choice of electrode array, intraoperative imaging and the use of navigation were the most important factors. Rehabilitation results were generally very positive and corresponded to the expectation depending on the duration of deafness, if no additional handicaps were present.


Assuntos
Implante Coclear/métodos , Implante Coclear/estatística & dados numéricos , Implantes Cocleares/estatística & dados numéricos , Correção de Deficiência Auditiva/métodos , Correção de Deficiência Auditiva/estatística & dados numéricos , Orelha Interna/anormalidades , Orelha Interna/cirurgia , Adolescente , Criança , Pré-Escolar , Correção de Deficiência Auditiva/instrumentação , Orelha Interna/diagnóstico por imagem , Feminino , Alemanha/epidemiologia , Transtornos da Audição , Humanos , Incidência , Lactente , Masculino , Radiografia , Estudos Retrospectivos , Resultado do Tratamento
16.
Int J Gynaecol Obstet ; 95(1): 66-72, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16926014

RESUMO

OBJECTIVE: To examine whether alcohol abuse (ALC) continued to be a health hazard to pregnant women in the 1990s. STUDY DESIGN: Analysis of a perinatal data base comprising 170,258 women with singleton pregnancies. Univariate cross table analysis and logistic regression were conducted to examine the association between alcohol abuse and congenital malformations coded according to the International Classification of Diseases (ICD). RESULTS: 14,727/170,258 mothers (8.6%) admitted to ALC during pregnancy and 36,705/170,258 (21.6%) to smoking. Anomaly rates for ALC (365/14,092, 4.3%) vs. Non-ALC (6187/149,344, 4.0%) differed significantly (p<0.001). The rates of specific anomalies varied between <0.1% and 1.1%. Odds ratios for 16 ICD 9 anomaly categories were >1 in 14 instances overall (Sign test, p=0.004), in 12 instances in women <30 years (p=0.08), and in 13 instances in women over 30 years (p=0.02). Congenital anomalies of the "respiratory system" (ICD9 748), of "genital organs" (ICD9 752.1), of the "integument" (ICD9 757), and "other anomalies of limbs/other musculoskeletal anomalies" (ICD 755/756) were statistically significantly associated with ALC, especially in women>30 years. CONCLUSION: ALC in pregnancy continued to be an important factor independently associated with an increased incidence of a broader range of congenital anomalies than previously recognized. Risk for anatomic anomalies was increased in offspring of ALC women over age 30, consistent with previous reports of increased risk of neurobehavioral abnormality in offspring of women over 30.


Assuntos
Anormalidades Induzidas por Medicamentos/etiologia , Alcoolismo/complicações , Transtornos do Espectro Alcoólico Fetal/epidemiologia , Anormalidades Induzidas por Medicamentos/epidemiologia , Adulto , Feminino , Alemanha/epidemiologia , Humanos , Modelos Logísticos , Paridade , Gravidez , Fatores de Risco , Fumar/epidemiologia
17.
FEBS Lett ; 508(2): 165-9, 2001 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11718709

RESUMO

In higher plants, chloroplast-destined precursor proteins are thought to be phosphorylated. Mediated by a specific 14-3-3 protein, these phosphorylated proteins bind to the chloroplast surface and are subsequently imported into the chloroplast. We demonstrate that also in the green alga Chlamydomonas reinhardtii the precursor of the small subunit of ribulose-1,5-bisphosphate carboxylase becomes phosphorylated by a plant protein kinase and that the phosphorylation site is located in the transit peptide. The phosphorylation status of the precursor protein regulates its import into chloroplasts especially at an early step during this process. The possible physiological function is discussed.


Assuntos
Chlamydomonas reinhardtii/metabolismo , Cloroplastos/metabolismo , Precursores de Proteínas/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo , Animais , Chlamydomonas reinhardtii/efeitos dos fármacos , Cloroplastos/efeitos dos fármacos , Eletroforese em Gel Bidimensional , Inibidores Enzimáticos/farmacologia , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Proteínas Quinases/metabolismo , Precursores de Proteínas/química , Sinais Direcionadores de Proteínas/fisiologia , Subunidades Proteicas , Transporte Proteico/efeitos dos fármacos , Ribulose-Bifosfato Carboxilase/química
18.
Eur J Biochem ; 268(8): 2315-21, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11298749

RESUMO

By studying the import of radioactively labelled small subunit of ribulose-1,5-bisphosphate carboxylase (pSS) into chloroplasts of the green alga C. reinhardtii cw-15 protein delivery to chloroplasts was found to vary during the cell cycle. Chloroplasts were isolated from highly synchronous cultures at different time points during the cell cycle. When pSS was imported into 'young' chloroplasts isolated early in the light period about three times less pSS was processed to small subunit SS than in 'mature' chloroplasts from the middle of the light period. In 'young' chloroplasts also, less pSS was bound to the envelope surface. During the second half of the light period the import competence of isolated chloroplasts decreased again when based on chlorophyll content or cell volume, but did not change significantly when related to chloroplast number. Measurements of pSS binding to the surface of chloroplasts of different age indicated that the adaptation of protein import competence during the cell cycle is due to a variation of the number of binding sites per chloroplast surface area, rather than to modulation of the binding constant.


Assuntos
Chlamydomonas/metabolismo , Cloroplastos/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Sítios de Ligação , Ciclo Celular , Divisão Celular , Citoplasma/metabolismo , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Cinética , Oxigênio/metabolismo , Fotossíntese/fisiologia , Plasmídeos/metabolismo , Ligação Proteica , Transporte Proteico , Fatores de Tempo
19.
Am J Obstet Gynecol ; 183(4): 815-22, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11035319

RESUMO

OBJECTIVE: This study was undertaken to identify correlates of abruptio placentae and to develop a mathematic model for the prediction of abruptio placentae. STUDY DESIGN: A total of 170,258 singleton birth records from 1991 to 1996 contained in the Schleswig-Holstein perinatal database were analyzed. Fifty-two recognized obstetric risk factors were subjected to univariate analysis. Correlates of abruptio placentae then underwent stepwise forward binary logistic regression. A constant value B(0), coefficients B(1) through B(p), an odds ratio, and a 95% confidence interval were calculated for individual correlates. RESULTS: Abruptio placentae occurred in 874 of 170,258 singleton gestations (0.5%). Of the 52 risk factors 31 proved to be correlates of abruptio placentae, with 16 among primiparous women and 25 among multiparous women. Ten correlates for primiparous, women and 13 for multiparous women emerged from the linear regression, with 7 correlates being shared by both primiparous and multiparous women. CONCLUSION: The probability that abruptio placentae will occur (p) can be calculated according to the following expression: p = e (z)/(1 + e (z)), where z = B(0) + B(1), em leaderB(p). For example, for a primiparous woman who smokes with bleeding at >28 weeks' gestation and a male fetus in the breech position, the following calculation would yield the chance of abruptio placentae:z = -2.25 + 2.51 + 0.41 + 0.24 + 0.60 = 1.51; p = e (1.51)/ (1 + e (1.51)) = 4. 53/5.53 = 0.82, or 82%.


Assuntos
Descolamento Prematuro da Placenta/etiologia , Modelos Biológicos , Descolamento Prematuro da Placenta/epidemiologia , Estudos de Casos e Controles , Cesárea , Feminino , Previsões , Alemanha , Humanos , Incidência , Trabalho de Parto Induzido , Idade Materna , Paridade , Gravidez , Gravidez Múltipla , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco
20.
Biochem J ; 344 Pt 2: 391-5, 1999 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-10567220

RESUMO

Proteins synthesized in the cytoplasm and destined for importation into the chloroplast across the double envelope membrane contain an N-terminal transit sequence which upon import is cleaved off by a stromal-processing peptidase. Since for stromal-residing proteins no intermediates have ever been found in vivo, it is assumed that precursor proteins are cleaved to the mature size by one proteolytic event which occurs immediately after translocation across both envelope membranes. During import of the precursor of the small subunit of ribulose-1,5-bisphosphate carboxylase (pSS) into isolated chloroplasts of Chlamydomonas we identified an intermediate-sized product, called iSS. It might be identical to a previously described iSS obtained in vitro by a partially purified soluble chloroplast protease [Su and Boschetti (1993) Eur. J. Biochem. 217, 1039-1047]. The kinetics of the formation of iSS in chloroplasts suggest that pSS is processed to the mature small subunit (SS) not by one, but by two steps via this intermediate product. Since, after an induction period, the ratio of iSS/SS was constant under various experimental conditions of import, the formation of iSS was considered not to be a side-reaction. The location of iSS in the intermembrane space of the envelope, as suggested by protease treatment of chloroplasts, questions the one-step translocation mechanism of precursor import into chloroplasts.


Assuntos
Chlamydomonas reinhardtii/metabolismo , Cloroplastos/metabolismo , Processamento de Proteína Pós-Traducional , Ribulose-Bifosfato Carboxilase/metabolismo , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Animais , Transporte Biológico/efeitos da radiação , Compartimento Celular , Endopeptidases/metabolismo , Membranas Intracelulares/metabolismo , Luz , Dados de Sequência Molecular , Sinais Direcionadores de Proteínas/metabolismo , Tilacoides/metabolismo
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