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1.
Nature ; 630(8017): 720-727, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38839949

RESUMO

Spermatozoa harbour a complex and environment-sensitive pool of small non-coding RNAs (sncRNAs)1, which influences offspring development and adult phenotypes1-7. Whether spermatozoa in the epididymis are directly susceptible to environmental cues is not fully understood8. Here we used two distinct paradigms of preconception acute high-fat diet to dissect epididymal versus testicular contributions to the sperm sncRNA pool and offspring health. We show that epididymal spermatozoa, but not developing germ cells, are sensitive to the environment and identify mitochondrial tRNAs (mt-tRNAs) and their fragments (mt-tsRNAs) as sperm-borne factors. In humans, mt-tsRNAs in spermatozoa correlate with body mass index, and paternal overweight at conception doubles offspring obesity risk and compromises metabolic health. Sperm sncRNA sequencing of mice mutant for genes involved in mitochondrial function, and metabolic phenotyping of their wild-type offspring, suggest that the upregulation of mt-tsRNAs is downstream of mitochondrial dysfunction. Single-embryo transcriptomics of genetically hybrid two-cell embryos demonstrated sperm-to-oocyte transfer of mt-tRNAs at fertilization and suggested their involvement in the control of early-embryo transcription. Our study supports the importance of paternal health at conception for offspring metabolism, shows that mt-tRNAs are diet-induced and sperm-borne and demonstrates, in a physiological setting, father-to-offspring transfer of sperm mitochondrial RNAs at fertilization.


Assuntos
Dieta Hiperlipídica , Epigênese Genética , Mitocôndrias , RNA Mitocondrial , Espermatozoides , Animais , Feminino , Humanos , Masculino , Camundongos , Índice de Massa Corporal , Dieta Hiperlipídica/efeitos adversos , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Embrião de Mamíferos/metabolismo , Epididimo/citologia , Epigênese Genética/genética , Fertilização/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Camundongos Endogâmicos C57BL , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Obesidade/genética , Obesidade/metabolismo , Obesidade/etiologia , Oócitos/metabolismo , Sobrepeso/genética , Sobrepeso/metabolismo , Herança Paterna/genética , RNA Mitocondrial/genética , RNA Mitocondrial/metabolismo , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/metabolismo , RNA de Transferência/genética , RNA de Transferência/metabolismo , Espermatozoides/metabolismo , Testículo/citologia , Transcrição Gênica
2.
Cryobiology ; 100: 63-71, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33826944

RESUMO

We compared the results of using egg yolk plasma (EYP) instead of egg yolk (EY) in a TRIS-based Equex STM Paste freezing extender system for dog semen [25]. We also tested whether the addition of lecithin and catalase to the EYP extenders would improve results. Fractionated semen collection was done in 17 stud dogs and the sperm rich fraction diluted with different extenders in 2 steps: (I) TRIS-fructose-citric acid extender (TRIS) containing 20% egg yolk (EY) and 3% glycerol [25], (II) TRIS containing 20% egg yolk plasma (EYP) and 3% glycerol, and (III) TRIS containing 20% EYP and 0.8% lecithin (EYP-L) and 3% glycerol. After equilibration the second dilution step was done: samples with (I) were diluted with TRIS-EY with 7% glycerol and 1% Equex STM paste [25]; samples with (II) and (III) were divided in 2 aliquots each, and one part diluted with TRIS-EYP or TRIS-EYP-L, both containing 7% glycerol and 1% Equex STM paste, and the other one part with the same extenders containing additionally 300 I.U./mL catalase. After freezing and thawing, samples were analyzed by CASA and sperm chromatin structure assay (SCSA); reactive oxygen species (ROS), degree of apoptosis and zona binding ability were determined. Semen samples with TRIS-EY with a final concentration of 5% glycerol and 0.5% Equex STM paste [25] showed best post thaw progressive motility (P), most intact cells, lowest percentage of ROS, acrosome damages, dead and apoptotic cells. Curvilinear velocity (VCL), DNA fragmentation, morphological abnormalities and zona binding ability did not differ between groups. Replacement of egg yolk by EYP increased the ROS and late apoptotic cells. Addition of lecithin and catalase to EYP containing extenders decreased motility and increased complete apoptosis. We conclude that egg yolk is superior to EYP in the here investigated extenders. The TRIS-based extender [25] with EYP could not be improved by addition of lecithin and catalase; however, in-vivo fertilization capacity of the here examined extenders remains to be investigated.


Assuntos
Preservação do Sêmen , Animais , Catalase , Criopreservação/métodos , Crioprotetores/farmacologia , Cães , Gema de Ovo , Congelamento , Humanos , Lecitinas , Masculino , Sêmen , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides
3.
Osteoarthritis Cartilage ; 26(12): 1627-1635, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30099114

RESUMO

OBJECTIVE: To investigate the performance of the Michigan Hand Outcomes Questionnaire (MHQ) in hand osteoarthritis (OA) by evaluating truth, discrimination and feasibility. DESIGN: Symptomatic hand OA patients from the Hand Osteoarthritis in Secondary Care (HOSTAS) cohort completed questionnaires (demographics, MHQ, Australian/Canadian Hand Osteoarthritis Index [AUSCAN], Functional Index for Hand Osteoarthritis [FIHOA] and visual analogue scale [VAS] pain) at baseline (n = 383), 1- and 2-year follow-up (n = 312, n = 293). Anchor questions at follow-up assessed whether pain/function levels were (un)acceptable and had changed compared to baseline. Correlations between MHQ and other pain/function questionnaires were calculated. Validity of unique MHQ domains (work performance, aesthetics, satisfaction), discrimination across disease stages, and responsiveness were assessed by categorizing patients by external anchors (employment, joint deformities, erosions, and anchor questions). Between-group differences were assessed with linear regression, probability plots and comparison of medians. RESULTS: MHQ pain and function subscales correlated moderately-to-good with other instruments (rs 0.63-0.81). Work performance scores were worse in patients with reduced working capacity than in employed patients. Aesthetics scores were worse in patients with more deformities. Patients with unacceptable complaints had worse satisfaction scores. All pain/function instruments discriminated between patients with acceptable vs unacceptable pain/function, while only MHQ activities of daily living (ADL), FIHOA, and MHQ aesthetics could discriminate between erosive and non-erosive disease. MHQ and AUSCAN were most responsive. CONCLUSIONS: MHQ has several unique aspects and advantages justifying its use in hand OA, including the unique assessment of work performance, aesthetics, and satisfaction. However, MHQ, AUSCAN and FIHOA appear to measure different aspects of pain and function.


Assuntos
Articulação da Mão/fisiopatologia , Osteoartrite/reabilitação , Atividades Cotidianas , Idoso , Avaliação da Deficiência , Emprego , Feminino , Seguimentos , Força da Mão/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/complicações , Osteoartrite/fisiopatologia , Avaliação de Resultados em Cuidados de Saúde/métodos , Dor/etiologia , Medição da Dor/métodos , Índice de Gravidade de Doença , Inquéritos e Questionários
4.
Anat Rec (Hoboken) ; 300(11): 1935-1941, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28971623

RESUMO

The anatomy of large cetaceans has been well documented, mostly through dissection of dead specimens. However, the difficulty of studying the world's largest animals in their natural environment means the functions of anatomical structures must be inferred. Recently, non-invasive tracking devices have been developed that measure body position and orientation, thereby enabling the detailed reconstruction of underwater trajectories. The addition of cameras to the whale-borne tags allows the sensor data to be matched with real-time observations of how whales use their morphological structures, such as flukes, flippers, feeding apparatuses, and blowholes for the physiological functions of locomotion, feeding, and breathing. Here, we describe a new tag design with integrated video and inertial sensors and how it can be used to provide insights to the function of whale anatomy. This technology has the potential to facilitate a wide range of discoveries and comparative studies, but many challenges remain to increase the resolution and applicability of the data. Anat Rec, 300:1935-1941, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Sistemas de Informação Geográfica/instrumentação , Natação/fisiologia , Gravação em Vídeo/instrumentação , Baleias/anatomia & histologia , Animais , Fenômenos Biomecânicos , Meio Ambiente , Comportamento Alimentar/fisiologia , Oceanos e Mares , Orientação , Tecnologia de Sensoriamento Remoto/instrumentação , Tecnologia de Sensoriamento Remoto/métodos , Respiração , Gravação em Vídeo/métodos , Baleias/fisiologia
5.
Br J Cancer ; 109(6): 1625-35, 2013 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-23969726

RESUMO

BACKGROUND: Gastrointestinal stromal tumours (GIST) are characterised by high expression of KIT and ETV1, which cooperate in GIST oncogenesis. Our aim was to identify microRNAs that are deregulated in GIST, have a role in GIST pathogenesis, and could potentially be used as therapeutic tool. METHODS: Differentially expressed microRNAs between primary GIST (n=50) and gastrointestinal leiomyosarcomas (GI-LMS, n=10) were determined using microarrays. Selected microRNA mimics were transfected into GIST-882 and GIST-T1 cell lines to study the effects of microRNA overexpression on GIST cells. Luciferase reporter assays were used to establish regulation of target genes by selected microRNAs. RESULTS: MiR-17-92 and miR-221/222 cluster members were significantly (P<0.01) lower expressed in GIST vs GI-LMS and normal gastrointestinal control tissues. MiR-17/20a/222 overexpression in GIST cell lines severely inhibited cell proliferation, affected cell cycle progression, induced apoptosis and strongly downregulated protein and--to a lesser extent--mRNA levels of their predicted target genes KIT and ETV1. Luciferase reporter assays confirmed direct regulation of KIT and ETV1 by miR-222 and miR-17/20a, respectively. CONCLUSION: MicroRNAs that may have an essential role in GIST pathogenesis were identified, in particular miR-17/20a/222 that target KIT and ETV1. Delivering these microRNAs therapeutically could hold great potential for GIST management, especially in imatinib-resistant disease.


Assuntos
Proteínas de Ligação a DNA/genética , Tumores do Estroma Gastrointestinal/genética , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-kit/genética , Fatores de Transcrição/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/genética , Carcinogênese/genética , Processos de Crescimento Celular/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/patologia , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Família Multigênica , Proteínas Proto-Oncogênicas c-kit/metabolismo , Fatores de Transcrição/metabolismo , Transfecção
6.
Oncogene ; 32(36): 4284-93, 2013 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-23045278

RESUMO

Epithelial ovarian cancer is the most lethal gynecological malignancy in the Western world. A major impediment for the successful treatment is the development of drug resistance. The molecular processes that contribute to resistance have been extensively studied; however, there is not much known about regulation by microRNAs (miRNAs). We compared miRNA expression profiles of an isogenic cisplatin-sensitive and -resistant ovarian cancer cell line pair (A2780/A2780 DDP) and found 27 miRNAs to be differentially expressed (2-fold). Five of these, including the family members miR-141/200c, showed a correlation with cisplatin sensitivity in the NCI-60 panel. Overexpression of miR-141 resulted in enhanced resistance to cisplatin in ovarian cancer cell lines. We next correlated the expression level of miR-141 in 132 primary ovarian tumors (108 serous and 24 non-serous) with response to platinum-based chemotherapy. Although no differences were observed in the serous tumors, miR-141 levels were higher in non-serous ovarian tumors that did not respond well to therapy (platinum-free interval <6 months). We demonstrate that miR-141 directly targets KEAP1, and that downregulation of KEAP1 induces cisplatin resistance. Conversely, overexpression of KEAP1 significantly enhanced cisplatin sensitivity. Expression of KEAP1 with its 3'-UTR, and a 3'-UTR in which the miR-141 target site has been mutated, revealed that miR-141 regulates KEAP1 upon exposure to cisplatin. Finally, we show that the NF-κB pathway, which can be regulated by KEAP1, is activated upon miR-141 overexpression, and that inhibition of this pathway partially reverses miR-141-mediated cisplatin resistance. These findings demonstrate that the miR-141-mediated regulation of KEAP1 has a crucial role in the cellular response to cisplatin.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/genética , MicroRNAs/genética , Neoplasias Ovarianas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Cisplatino/uso terapêutico , Análise por Conglomerados , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Transdução de Sinais
7.
West Indian Med J ; 62(2): 127-34, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24564062

RESUMO

OBJECTIVE: To assess the prevalence of child abuse among high school students in Curacao. METHODS: A questionnaire survey among high school students up to 17 years of age was conducted. The questionnaire was based on existing literature and validated questionnaires. The questionnaire used was analysed and adapted to the situation in Curaçao by a panel of experts on child abuse. The primary objective was to gain insight into the incidence, prevalence and various forms of child abuse among students in Curaçao. Five forms of child abuse are distinguished in the literature: physical abuse, emotional abuse, sexual abuse, neglect and exploitation. Furthermore, the degree of confidence of the students in general practitioners (GPs) as care providers in the field of child abuse was explored. RESULTS: Questionnaires from 545 of the 628 respondents were included. In total, 43% of the respondents had ever-experienced an event which could be defined as (a form of) child abuse. More than one-third of the respondents reporting child abuse ever had an experience that could be interpreted as physical abuse. More than 15% of the respondents reporting child abuse had experienced sexual abuse. Girls experienced significantly more sexual abuse than boys. Emotional abuse in the last year was experienced by 3% of the respondents. One per cent of the respondents ever-experienced neglect. According to most respondents, GPs were not seen as care providers in cases of child abuse; they believed that GPs were mainly to be consulted for illnesses or physical symptoms and not for forms of child abuse. CONCLUSION: The prevalence of ever-having-experienced a form of child abuse is estimated at 431 per 1000 students. Child abuse, particularly physical abuse, is common in Curaçao, and is probably comparable to other surrounding countries. General practitioners were not seen as care providers in identifying and reporting cases of child abuse according to most respondents.


Assuntos
Maus-Tratos Infantis/estatística & dados numéricos , Adolescente , Criança , Abuso Sexual na Infância/estatística & dados numéricos , Feminino , Humanos , Masculino , Antilhas Holandesas/epidemiologia , Prevalência , Inquéritos e Questionários
9.
West Indian Med J ; 60(5): 564-70, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22519235

RESUMO

BACKGROUND: Most islands in the West Indies do not have liberal laws on abortion, nor laws on pregnancy prevention programmes (contraception). We present results of a literature review about the attitude of healthcare providers and women toward (emergency) contraception and induced abortion, prevalence, methods and juridical aspects of induced abortion and prevention policies. METHODS: Articles were obtained from PubMed, EMBASE, MEDLINE, PsychlNFO and Soclndex (1999 to 2010) using as keywords contraception, induced abortion, termination of pregnancy, medical abortion and West Indies. RESULTS: Thirty-seven articles met the inclusion criteria: 18 on contraception, 17 on induced abortion and two on both subjects. Main results indicated that healthcare providers' knowledge of emergency contraception was low. Studies showed a poor knowledge of contraception, but counselling increased its effective use. Exact numbers about prevalence of abortion were not found. The total annual number of abortions in the West Indies is estimated at 300 000; one in four pregnancies ends in an abortion. The use of misoprostol diminished the complications of unsafe abortions. Legislation of abortion varies widely in the different islands in the West Indies: Cuba, Puerto Rico, Martinique, Guadeloupe and St Martin have legal abortions. Barbados was the first English-speaking island with liberal legislation on abortion. All other islands have restrictive laws. CONCLUSION: Despite high estimated numbers of abortion, research on prevalence of abortion is missing. Studies showed a poor knowledge of contraception and low use among adolescents. Most West Indian islands have restrictive laws on abortion.


Assuntos
Aborto Induzido/legislação & jurisprudência , Aborto Induzido/estatística & dados numéricos , Comportamento Contraceptivo , Anticoncepção Pós-Coito , Conhecimentos, Atitudes e Prática em Saúde , Mulheres/psicologia , Adolescente , Adulto , Atitude Frente a Saúde , Feminino , Humanos , Gravidez , Índias Ocidentais/epidemiologia
10.
Br J Pharmacol ; 159(4): 898-908, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20067471

RESUMO

BACKGROUND: Solute carriers (SLCs), in particular organic cation transporters (OCTs), have been implicated in the cellular uptake of platinum-containing anticancer compounds. The activity of these carriers may determine the pharmacokinetics and the severity of side effects, including neuro- and nephrotoxicity of platinum-based chemotherapy. As decreased drug accumulation is a key mechanism of platinum resistance, SLCs may also contribute to the development of resistance. Here, we define the role of hSLC22A2 (OCT2) in the cellular uptake of platinum compounds. EXPERIMENTAL APPROACH: Human embryonic kidney (HEK) 293 cells stably expressing the hSLC22A2 gene (HEK293/hSLC22A2) were used in platinum accumulation studies. Following a 2 h exposure to various platinum compounds (100 microM), intracellular platinum levels were determined by flameless atomic absorption spectrometry. KEY RESULTS: HEK293/hSLC22A2 cells, compared with HEK293/Neo control cells, displayed significant increases in oxaliplatin (28.6-fold), Pt[DACH]Cl(2) (20.6-fold), ormaplatin (8.1-fold), tetraplatin (4.5-fold), transplatin (3.7-fold) and cisplatin (1.3-fold), but not carboplatin. SLC22A2-mediated transport could be inhibited by 1-methyl-4-phenylpyridinium. Furthermore, hSLC22A2-mediated oxaliplatin and cisplatin accumulation was time- and concentration-dependent, but non-saturable. Expression of hSLC22A2 in HEK293 cells resulted in enhanced sensitivity to oxaliplatin (12-fold) and cisplatin (1.8-fold). Although, hSLC22A2 mRNA expression was frequently found in ovarian cancer cell lines, its expression in clinical ovarian cancer specimens (n= 80) was low and did not correlate with the treatment outcome of platinum-based regimens. CONCLUSIONS AND IMPLICATIONS: The hSLC22A2 drug transporter is a critical determinant in the uptake and cytotoxicity of various platinum compounds, particularly oxaliplatin.


Assuntos
Antineoplásicos/metabolismo , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Compostos Organoplatínicos/metabolismo , Compostos de Platina/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Transporte Biológico , Carboplatina/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/metabolismo , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Cinética , Proteínas de Transporte de Cátions Orgânicos/antagonistas & inibidores , Proteínas de Transporte de Cátions Orgânicos/genética , Transportador 2 de Cátion Orgânico , Compostos Organoplatínicos/farmacologia , Compostos Organoplatínicos/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Oxaliplatina , Compostos de Platina/farmacologia , Compostos de Platina/uso terapêutico , RNA Mensageiro/metabolismo , Espectrofotometria Atômica , Transfecção , Resultado do Tratamento
11.
West Indian Med J ; 58(6): 610-3, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20583695

RESUMO

We describe five pitfalls of medical abortion: ectopic pregnancy not terminated after misoprostol, but without negative side-effects; long-term vaginal blood loss with suspicious retained products which disappeared spontaneously; a patient with uterus myomatatosus with severe pain and retained products in the uterus; repetition of misoprostol because of retained products in the uterus after two weeks and an allergic reaction to methotrexate. Despite these pitfalls, there are enough benefits to consider medical abortion with methotrexate and misoprostol as a safe method with a high success rate of more than 91% and a good alternative for surgical abortion. An invasive procedure is not necessary, there are no long-term complications and it can be performed at an earlier stage, which makes it more acceptable in society. In Curaçao, where abortion is legally restricted, medical abortion is performed with methotrexate and misoprostol. In countries where abortion is legal, mifepristone and misoprostol are the first choice.


Assuntos
Abortivos/administração & dosagem , Aborto Induzido/métodos , Misoprostol/administração & dosagem , Administração Intravaginal , Adulto , Dilatação e Curetagem , Feminino , Humanos , Leiomiomatose/complicações , Leiomiomatose/diagnóstico por imagem , Gravidez , Complicações Neoplásicas na Gravidez/diagnóstico por imagem , Falha de Tratamento , Ultrassonografia , Adulto Jovem
12.
Ned Tijdschr Geneeskd ; 152(9): 504-8, 2008 Mar 01.
Artigo em Holandês | MEDLINE | ID: mdl-18389885

RESUMO

OBJECTIVE: To evaluate the results of early medicinal pregnancy termination. DESIGN: Prospective, non-blinded, clinical study. METHOD: Between 2001 and 2005, 371 women presented to a medium-sized solo general practice in the centre of Willemstad, Curaçao, to request termination of an undesired pregnancy. Ofthese women, 74 first indicated a preference for abortion via curettage, and the remaining 297 chose to be treated medicinally. In the first trimester of the pregnancy, they were given methotrexate i.m. and misoprostol vaginally 3-5 days later, or only misoprostol vaginally when methotrexate was unavailable. The result was evaluated by abdominal echography two days after the treatment. RESULTS: The result of the medicinal pregnancy termination could be determined in 271 of the 297 women. In 219 (81%) of these, the pregnancy had been terminated after a single treatment, and in 29 (11%) success was achieved after a second vaginal administration of misoprostol. The total success rate of the medicinal pregnancy termination was 92% (248/271). Curettage was required in 23 women (8%) after the medicinal treatment had failed. There was no significant difference in success rate between treatment with the methotrexate-misoprostol combination and treatment with misoprostol alone. CONCLUSION: Medicinal pregnancy termination with methotrexate and misoprostol, or with misoprostol alone, was a safe method with a relatively small risk of an ongoing pregnancy. It was a good alternative for surgical abortion.


Assuntos
Abortivos não Esteroides/administração & dosagem , Aborto Induzido/métodos , Metotrexato/administração & dosagem , Misoprostol/administração & dosagem , Aborto Induzido/efeitos adversos , Adolescente , Adulto , Curetagem/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Antilhas Holandesas , Gravidez , Estudos Prospectivos , Resultado do Tratamento
13.
Tijdschr Diergeneeskd ; 131(5): 173; author reply 173, 2006 Mar 01.
Artigo em Holandês | MEDLINE | ID: mdl-16532792
14.
Ann Surg ; 240(6): 949-53; discussion 953-4, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15570200

RESUMO

OBJECTIVE: To analyze the utility of quick intraoperative parathyroid hormone (PTH) measurement in the surgical management of primary hyperparathyroidism. BACKGROUND DATA: The use of intraoperative PTH monitoring is well established in the surgery of primary hyperparathyroidism. However, some false-negative predictions lead to unnecessary explorations; furthermore, surgeons are becoming increasingly dependent on hormone measurement for intraoperative decisions, which raises concerns about the cost-effectiveness of the method. METHODS: A retrospective analysis of 268 neck explorations performed for primary hyperparathyroidism using intraoperative PTH monitoring from April 2001 to February 2003 was done. We used the criterion of "biologic recovery" of hyperfunctioning tissue, defined as a more than 50% decrease in PTH level from baseline value at 5 minutes after excision to predict the outcome of successful parathyroidectomy documented by normal postoperative serum calcium level. Additionally, we also sampled PTH at 10 minutes, 30 minutes, and the morning after surgery to compare the predictive value of delayed sampling. Patients were classified according to the prediction being concordant or discordant with the outcome. The data were analyzed using a 2 x 2 table construct for each of the sampling times, therefore providing sequential sensitivity, specificity, positive and negative predictive values, and overall accuracy of the predictions. RESULTS: Concordance or overall accuracy of prediction (true positives and negatives) was obtained in 229 cases (85.4%), and discordance or failure of prediction (false positives and negatives) was obtained in 34 cases (12.7%) at T5. On analyzing the iPTH prediction at T10, T30, and D1 among the group of 33 false negatives, we found that 28 (10.4%) patients reached the concordance at 30 minutes, while by the first day 32 patients (12.3%) had achieved concordance. Thus, there was a progressive increase in sensitivity and overall accuracy, but more importantly, in the negative predictive value reaching 88.9% on the day after surgery. CONCLUSIONS: The method of sampling PTH intraoperatively at 5 minutes has a high positive predictive value (99.5%) but a low negative predictive value (19.5%), which can lead to unnecessary explorations and a delay in the operative procedure. The negative predictive value increases substantially at 30 minutes and is best on the day after surgery. We suggest giving up the intraoperative measurement of PTH to adopt the first day postoperative measurement of PTH as a predictor of successful parathyroidectomy.


Assuntos
Hiperparatireoidismo/cirurgia , Imunoensaio/métodos , Hormônio Paratireóideo/sangue , Paratireoidectomia , Análise Custo-Benefício , Humanos , Hiperparatireoidismo/sangue , Imunoensaio/economia , Medições Luminescentes/economia , Monitorização Intraoperatória , Período Pós-Operatório , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
16.
Ann Chir ; 127(8): 612-8, 2002 Oct.
Artigo em Francês | MEDLINE | ID: mdl-12491636

RESUMO

AIM OF THE STUDY: The aim of this prospective cohort study was to identify the early criteria potentially predictive for outcome of permanent hypocalcemia after thyroidectomy. PATIENTS AND METHODS: Serum calcium (Ca) et phosphorus (Ph) were measured daily until discharge in 2035 consecutive patients undergoing bilateral thyroidectomy. In all patients experiencing postoperative hypocalcemia, defined as a Ca < 8.0 mg/dl on two consecutive days, parathyroid hormone was measured prior initiation of calcium therapy et discharge (early PTH), et blood sample was also obtained 7 to 14 days after discharge for Ca et Ph measurements (delayed Ca et Ph). These patients were then followed up until complete resolution of hypocalcemia or at least one year. Those still needing substitutive therapy to maintain normocalcemia one year after surgery were considered to have permanent hypocalcemia. Correlation of outcome with clinical characteristics, postoperative Ca et Ph levels, early PTH, et delayed Ca et Ph were examined with univariate analysis et multivariate logistic regression. RESULTS: Postoperative hypocalcemia occurred in 153 patients (7.5%) and spontaneously recovered in all but 7 patients (0.3%). Delayed Ca, and delayed Ph were found to be predictive for outcome of hypocalcemia by univariate analysis (p < 0.01). Relative risk to develop permanent hypocalcemia was 15 for patients with early PTH < 12 pg/ml, 52 when delayed Ph was > 4.0 mg/dl, and 121 when delayed Ca was < 8.0 mg/dl. None of the 113 patients with delayed Ca > or = 8.0 mg/dl and delayed Ph < or = 4.0 mg/dl developed permanent hypocalcemia, in contrast to 1 out of 31 patients (3%) with delayed Ca > 8.0 mg/dl or delayed Ph > 4.0 mg/dl, and 6 out of 9 patients (66%) with delayed Ca < 8.0 mg/dl and delayed Ph > 4.0 mg/dl. Both delayed Ca and delayed Ph appeared as independent factors predicting outcome of hypocalcemia at one year with multivariate logistic regression analysis. CONCLUSION: Delayed serum calcium and phosphorus levels, when measured one week after starting calcium therapy but prior to administration of any vitamin D analogs, accurately predict outcome of hypocalcemia after thyroidectomy. Patients with delayed Ca under 8.0 mg/dl and/or delayed Ph above 4.0 mg/dl are at high risk to develop permanent hypocalcemia.


Assuntos
Hipocalcemia/etiologia , Complicações Pós-Operatórias , Tireoidectomia/efeitos adversos , Adulto , Cálcio/sangue , Cálcio/uso terapêutico , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fósforo/sangue , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco
17.
Cancer Res ; 61(19): 6982-6, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11585720

RESUMO

The therapeutic potential of cisplatin, one of the most active and widely used anticancer drugs, is severely limited by the occurrence of cellular resistance. In this study, using budding yeast Saccharomyces cerevisiae as a model organism to identify novel drug resistance genes, we found that disruption of the yeast gene SKY1 (serine/arginine-rich protein-specific kinase from budding yeast) by either transposon insertion or one-step gene replacement conferred cellular resistance to cisplatin. Heterologous expression of the human SKY1 homologue SRPK1 (serine/arginine-rich protein-specific kinase) in SKY1 deletion mutant yeast cells restored cisplatin sensitivity, suggesting that SRPK1 is a cisplatin sensitivity gene, the inactivation of which could lead to cisplatin resistance. Subsequently, we investigated the role of SRPK1 in cisplatin sensitivity and resistance in human ovarian carcinoma A2780 cells using antisense oligodeoxynucleotides. Treatment of A2780 cells with antisense oligodeoxynucleotides directed against the translation initiation site of SRPK1 led to down-regulation of SRPK1 protein and conferred a 4-fold resistance to cisplatin. The human SRPK1 gene has not been associated with drug resistance before. Our new findings strongly suggest that SRPK1 is involved in cisplatin-induced cell kill and indicate that SRPK1 might potentially be of importance for studying clinical drug resistance.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/efeitos dos fármacos , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Humanos , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/farmacologia , Neoplasias Ovarianas/enzimologia , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Serina-Treonina Quinases/genética , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Células Tumorais Cultivadas
18.
Carbohydr Res ; 333(2): 165-71, 2001 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-11448678

RESUMO

The acceptor specificity of three major isoforms of UDP-GalNAc:polypeptide N-acetylgalactosaminyltranferases (murine recombinant proteins GaNTase-T1, -T2 and -T3) was investigated using the synthetic peptide (GTTPSPVPTTSTTSAP) containing clusters of threonine residues mimicking the mucin tandem repeat unit of MUC5AC. The O-glycosylated products obtained after in vitro reactions were fractionated by capillary electrophoresis and the purified glycopeptides were characterized by MALDI mass spectrometry (number of O-GalNAc residues) and by Edman degradation (site location). A maximum of three GalNAc residues was transferred into the MUC5AC motif peptide and the preferential order of incorporation for each GaNTase isoform was determined. Our results suggest that clusters of threonine appear to be essential for site recognition of peptide backbone by the ubiquitous GaNTases and also support the notion that the different GaNTase isoforms with varying substrate specificities are involved in a hierarchical order of O-glycosylation processing of the mucin-type O-glycoproteins.


Assuntos
Isoenzimas/metabolismo , N-Acetilgalactosaminiltransferases/metabolismo , Peptídeos/metabolismo , Motivos de Aminoácidos , Animais , Sítios de Ligação , Eletroforese Capilar , Glicosilação , Humanos , Camundongos , Mucinas/química , Peptídeos/química , Proteínas Recombinantes/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Especificidade por Substrato
19.
Biochem J ; 357(Pt 1): 313-20, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11415465

RESUMO

The recombinant proteins of the two novel UDP-N-acetylgalactosamine (GalNAc) glycopeptide:N-acetylgalactosaminyltransferases (designated gpGaNTase-T7 and gpGaNTase-T9) were assayed with O-glycosylated products obtained from the prior action of the ubiquitous transferases (GaNTase-T1 and GaNTase-T2) towards MUC5AC mucin motif peptides (GTTPSPVPTTSTTSAP and peptides with single amino acid substitutions, GTTPSAVPTTSTTSVP and GTTPSPVPTTSITSVP, that are a reflection of mucin molecule polymorphism). gpGaNTase-T9 is known to be expressed differentially and more abundantly than gpGaNTase-T7 in some tissues; the results of in vitro glycosylation also indicates a difference in acceptor substrate specificities between the gpGaNTase isoforms. With the use of capillary electrophoresis, MS and Edman degradation, our study suggests that, in the O-glycosylation of mucin-type proteins, approach and recognition signalling by gpGaNTase-T7 and gpGaNTase-T9 depend largely on the peptide's primary structure (for example the presence of multiple clusters of hydroxy amino acids and the number of GalNAc residues attached to the peptide backbone). O-glycosylation in terms of sites of attachment seems to be less random than previously described and, if sequential reactions are ordered throughout the Golgi stack, the complete O-glycosylation of the mucin molecules seems to be finely tuned to respond to specific damage to, or attack on, epithelia.


Assuntos
Mucinas/química , Mucinas/metabolismo , N-Acetilgalactosaminiltransferases/metabolismo , Sequência de Aminoácidos , Animais , Células COS , Chlorocebus aethiops , Glicosilação , Isoenzimas/metabolismo , Cinética , Dados de Sequência Molecular , Mucina-5AC , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Proteínas Recombinantes/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Especificidade por Substrato , Transfecção
20.
J Androl ; 22(1): 104-10, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11191073

RESUMO

This study was conducted to investigate the relationships between results of computer-assisted semen analysis (spermatozoal motility and sperm head morphometry) and fertility of boars. In addition, concentrations of insulin-like growth factor (IGF)-I and IGF-II in seminal plasma were determined. The nonreturn rate (NRR) and the number of live-born piglets were compatible with the requirements of artificial insemination for all boars included in this study. Semen samples of 12 boars (Pietrain; 3 ejaculates each) were evaluated for spermatozoal motility and sperm head dimensions using computer-assisted methods. Native semen samples were centrifuged, and seminal plasma was frozen at -20 degrees C until assayed for IGF-I and IGF-II by specific radioimmunoassays. Spermatozoa of boars with a higher NRR (>86%) had a significantly slower average velocity of motile spermatozoa when compared with that of boars with an NRR below 86%. High-fertility boars (NRR > 86%) had significantly smaller sperm heads than did boars with an NRR below 86%, and their sperm heads were less elongated. Substantial concentrations of IGF-I (8.4-22.2 ng/mL) and IGF-II (12.1-19.8 ng/mL) could be measured in porcine seminal plasma; however, there was no correlation between IGF levels and semen parameters or individual fertility.


Assuntos
Fator de Crescimento Insulin-Like II/análise , Fator de Crescimento Insulin-Like I/análise , Sêmen/química , Sêmen/citologia , Cabeça do Espermatozoide , Motilidade dos Espermatozoides , Animais , Fertilidade , Inseminação Artificial , Masculino , Suínos
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