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1.
Eur J Cancer ; 206: 114128, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38805957

RESUMO

Duodenal adenocarcinoma is a rare digestive cancer, often diagnosed at a late stage and harbours a poor prognosis. The arrival of immunotherapy has changed the prognosis of many neoplasia, including digestive adenocarcinomas with MSI-H status. Hereby, we describe three cases of MSI-H locally advanced duodenal adenocarcinoma who received neoadjuvant treatment with a PD1 inhibitor, pembrolizumab. A partial metabolic and endoscopic response was observed in all patients after 2 cycles. Duodenopancreatectomy was performed at the end of treatment (4-6 cycles), and anatomopathological analysis demonstrated pathological complete response in all patients. Our case series paves the way for prospectively exploring neoadjuvant immunotherapy in duodenal MSI-H adenocarcinoma and raises the question of organ sparing surgery in case of complete clinical response as observed in gastric and colo-rectal adenocarcinomas.


Assuntos
Adenocarcinoma , Anticorpos Monoclonais Humanizados , Neoplasias Duodenais , Instabilidade de Microssatélites , Terapia Neoadjuvante , Humanos , Adenocarcinoma/genética , Adenocarcinoma/terapia , Adenocarcinoma/patologia , Neoplasias Duodenais/genética , Neoplasias Duodenais/patologia , Neoplasias Duodenais/terapia , Terapia Neoadjuvante/métodos , Masculino , Idoso , Pessoa de Meia-Idade , Feminino , Anticorpos Monoclonais Humanizados/uso terapêutico , Imunoterapia/métodos , Inibidores de Checkpoint Imunológico/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Resultado do Tratamento
2.
Acta Gastroenterol Belg ; 86(2): 288-297, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37428161

RESUMO

Background and aims: Irritable Bowel Syndrome (IBS)-like symptoms are frequent following bariatric surgery. This study aims to evaluate the frequency of IBS symptoms severity before and after bariatric surgery and their association with short-chain fermentable carbohydrates (FODMAPs) consumption. Patients and methods: IBS symptoms severity in a cohort of obese patients was evaluated prospectively before, 6 and 12 months after bariatric surgery by validated questionnaires and tools (Irritable Bowel Syndrome Severity Scoring System (IBS SSS), Bristol Stool Scale (BSS), Quality of Life Short- Form-12 (SF-12), Hospital Anxiety and Depression scale (HAD)). FODMAPs consumption and its association with IBS symptom severity was evaluated by using a food frequency questionnaire focused on high-FODMAPs food consumption. Results: Fifty-one patients were included (41 female; mean age 41 years (SD: 12)), 84% received a sleeve gastrectomy, and 16% a Roux-en-Y gastric bypass. Symptoms compatible with IBS were observed in 43% of patients before surgery, in 58% of patients at 6 months and 33% at 12 months (NS, p-value=0,197 and 0,414). In a multivariate model, a significant association was found between the IBS SSS score and lactose consumption at 6 months (ß = + 58, 1; p = 0.03), and with polyols consumption at 12 months (ß = + 112,6; p = 0.01). Conclusions: Mild to moderate IBS symptoms are frequent in obese patients before bariatric surgery. A significant association between lactose and polyols consumption and IBS SSS score was observed after bariatric surgery, suggesting a potential link between the severity of IBS symptoms and some specific FODMAPs consumption.


Assuntos
Cirurgia Bariátrica , Síndrome do Intestino Irritável , Humanos , Feminino , Adulto , Síndrome do Intestino Irritável/epidemiologia , Síndrome do Intestino Irritável/etiologia , Dissacarídeos , Lactose , Estudos Prospectivos , Qualidade de Vida , Monossacarídeos , Cirurgia Bariátrica/efeitos adversos , Obesidade/epidemiologia , Obesidade/cirurgia
3.
Surg Endosc ; 36(9): 6558-6566, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35099626

RESUMO

BACKGROUND: Adverse economic conditions often prevent the widespread implementation of modern surgical techniques in third world countries such as in Sub-Sahara Africa. AIM OF THE STUDY: To demonstrate that a modern technique (laparoscopic totally extraperitoneal inguinal hernioplasty [TEP]) can safely be performed at significantly lower cost using inexpensive mesh material. SETTINGS: Douala University Hospital Gynecology, Obstetrics and Pediatrics and two affiliated centers, Ayos Regional Hospital and Edéa Regional Hospital in Cameroon. PATIENTS AND METHODS: Prospective randomized controlled trial (RCT) of consecutive adult patients presenting with primary inguinal hernia treated by TEP, comparing implantation of sterilized mosquito mesh (MM) with conventional polypropylene mesh (CM). Primary endpoints were peroperative, early and midterm postoperative complications and hernia recurrence at 30 months. RESULTS: Sixty-two patients (48 males) were randomized to MM (n = 32) or CM (n = 30). Groups were similar in age distribution and occupational features. Peroperative and early outcomes differed in terms of conversion rate (2/32 MM) due to external (electrical power supply) factors and mesh removal for early obstruction (1/30 CM). No outcome differences, including no recurrences, were noted after a median follow-up of 21 months. CONCLUSION: In this RCT with medium-term follow-up, TEP performed with MM appears not inferior to CM.


Assuntos
Culicidae , Hérnia Inguinal , Laparoscopia , Adulto , Animais , Camarões , Criança , Hérnia Inguinal/complicações , Herniorrafia/métodos , Humanos , Laparoscopia/métodos , Masculino , Dor Pós-Operatória/etiologia , Estudos Prospectivos , Telas Cirúrgicas/efeitos adversos , Resultado do Tratamento
5.
Reprod Fertil Dev ; 33(2): 82-90, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38769676

RESUMO

This review provides a snapshot of the current state-of-the-art of drying cells and spermatozoa. The major successes and pitfalls of the most relevant literature are described separately for spermatozoa and cells. Overall, the data published so far indicate that we are closer to success in spermatozoa, whereas the situation is far more complex with cells. Critical for success is the presence of xeroprotectants inside the spermatozoa and, even more so, inside cells to protect subcellular compartments, primarily DNA. We highlight workable strategies to endow gametes and cells with the right combination of xeroprotectants, mostly sugars, and late embryogenesis abundant (LEA) or similar 'intrinsically disordered' proteins to help them withstand reversible desiccation. We focus on the biological aspects of water stress, and in particular cellular and DNA damage, but also touch on other still unexplored issues, such as the choice of both dehydration and rehydration methods or approaches, because, in our view, they play a primary role in reducing desiccation damage. We conclude by highlighting the need to exhaustively explore desiccation strategies other than lyophilisation, such as air drying, spin drying or spray drying, ideally with new prototypes, other than the food and pharmaceutical drying strategies currently used, tailored for the unique needs of cells and spermatozoa.

6.
Cryobiology ; 92: 189-196, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31952948

RESUMO

Late Embryogenesis Abundant (LEA) proteins are commonly found in plants and other organisms capable of undergoing severe and reversible dehydration, a phenomenon termed "anhydrobiosis". Here, we have produced a tagged version for three different LEA proteins: pTag-RAB17-GFP-N, Zea mays dehydrin-1dhn, expressed in the nucleo-cytoplasm; pTag-WCOR410-RFP, Tricum aestivum cold acclimation protein WCOR410, binds to cellular membranes, and pTag-LEA-BFP, Artemia franciscana LEA protein group 3 that targets the mitochondria. Sheep fibroblasts transfected with single or all three LEA proteins were subjected to air drying under controlled conditions. After rehydration, cell viability and functionality of the membrane/mitochondria were assessed. After 4 h of air drying, cells from the un-transfected control group were almost completely nonviable (1% cell alive), while cells expressing LEA proteins showed high viability (more than 30%), with the highest viability (58%) observed in fibroblasts expressing all three LEA proteins. Growth rate was markedly compromised in control cells, while LEA-expressing cells proliferated at a rate comparable to non-air-dried cells. Plasmalemma, cytoskeleton and mitochondria appeared unaffected in LEA-expressing cells, confirming the protection conferred by LEA proteins on these organelles during dehydration stress. This is likely to be an effective strategy when aiming to confer desiccation tolerance to mammalian cells.


Assuntos
Criopreservação/métodos , Crioprotetores/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Proteínas de Plantas/farmacologia , Animais , Artemia/metabolismo , Células Cultivadas , Desidratação/metabolismo , Dessecação/métodos , Mitocôndrias/metabolismo , Proteínas de Plantas/metabolismo , Ovinos , Triticum/metabolismo , Água/metabolismo , Zea mays/metabolismo
7.
Ann R Coll Surg Engl ; 102(2): e23-e25, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31508987

RESUMO

Epidermoid cysts are rare lesions that can occur anywhere in the body. They are associated with elevated serum levels of CA 19-9. The spleen represents the most common site of intra-abdominal localisation. Only two cases of diaphragmatic epidermoid cyst are reported in the literature. We present the case of a 61-year-old woman with a small suprasplenic subdiaphragmatic cyst discovered during the investigation of left flank pain. The establishment of an adequate diagnosis was challenging due to the difficulty in specifying the exact localisation of the cyst, the extremely elevated CA 19-9 level of 19,000 and the high uptake on 18-fluoro-2-deoxy-D-glucose positron emission tomography. The definitive diagnosis followed complete surgical excision. Intra-abdominal epidermoid cysts are usually discovered incidentally on imaging for another reason. The cyst is lined by squamous epithelium responsible for the secretion of CA 19-9. The elevation of serum CA 19-9 is due to small rupture or increased intraluminal pressure followed by diffusion to the bloodstream. Surgery with en-bloc resection represents the optimal treatment to avoid any risk of recurrence. The definitive diagnosis is established by demonstrating positive immunohistopathological staining of epithelial cell to CA 19.9.


Assuntos
Antígeno CA-19-9/sangue , Diafragma/diagnóstico por imagem , Cisto Epidérmico/diagnóstico , Biomarcadores/sangue , Diafragma/cirurgia , Cisto Epidérmico/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X
8.
Acta Chir Belg ; 118(2): 94-98, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28927340

RESUMO

OBJECTIVES: Postoperative complications after Laparoscopic sleeve gastrectomy (LSG) can dramatically compromise patient's outcome. The aim of this study is to analyze the per- and postoperative short-term outcomes after LSG and to assess predictive risk factors of complications. METHODS: The study group consisted of 790 patients (610 women and 180 men) who underwent LSG In 2014. All interventions were performed by 18 experienced surgeons members of the Club Coelio. Data about preoperative work-up, surgical techniques, 30-days postoperative morbidity and mortality were collected. Endpoints were perioperative morbidity and mortality and assessment of potential risk factors for complications. RESULTS: Mean age and body mass index were respectively 39 years and 41.5kg/m2. Ninety-one patients (11.5%) had previous bariatric surgery. Morbidity rate was 4.7% (37/790) including 16 leaks (2.0%) and 9 bleedings (1.1%) and no deaths. Risk factors for leak were: previous adjustable banding (p = .0051), with no difference between removal of the banding and LSG in 1 or 2 steps, and type of endostapler (p = .0129). CONCLUSIONS: Leakage after Sleeve was rare but still observed even in experienced hands. The leak rate is particularly high when LSG is performed after adjustable gastric banding removal.


Assuntos
Gastroplastia/efeitos adversos , Laparoscopia/efeitos adversos , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/epidemiologia , Adolescente , Adulto , Idoso , Bélgica/epidemiologia , Feminino , Gastroplastia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade/tendências , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Adulto Jovem
9.
Acta Chir Belg ; 115: 81-2, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26021797

RESUMO

The aim of this case report is to outline the challenge and the feasibility of laparoscopic gastric bypass in a patient with situs inversus totalis. Situs inversus totalis does not seem to be a contraindication for laparoscopic surgery.


Assuntos
Derivação Gástrica , Laparoscopia , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Situs Inversus/complicações , Feminino , Humanos , Pessoa de Meia-Idade , Radiografia , Situs Inversus/diagnóstico por imagem , Situs Inversus/cirurgia
10.
Acta Chir Belg ; 115(1): 81-2, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27384902

RESUMO

The aim of this case report is to outline the challenge and the feasibility of laparoscopic gastric bypass in a patient with situs inversus totalis. Situs inversus totalis does not seem to be a contraindication for laparoscopic surgery.


Assuntos
Derivação Gástrica/métodos , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Situs Inversus/complicações , Índice de Massa Corporal , Feminino , Seguimentos , Humanos , Laparoscopia/métodos , Pessoa de Meia-Idade , Obesidade Mórbida/diagnóstico , Medição de Risco , Situs Inversus/diagnóstico , Resultado do Tratamento , Redução de Peso
11.
Hum Reprod ; 29(9): 1875-83, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25027441

RESUMO

STUDY QUESTION: Does blastomere biopsy (BB) of preimplantation embryos induce long-term effects on their growth and post-natal behavior? SUMMARY ANSWER: BB induces long-term effects on body weight and behavior in male mice. WHAT IS KNOWN ALREADY: BB is an essential technique for performing preimplantation genetic diagnosis (PGD), a screening test that can detect genetic abnormalities of embryos before their transfer in utero. There is limited understanding of the post-natal consequences and safety of BB. STUDY DESIGN, SIZE, DURATION: Offspring who had a BB performed as embryos, as well as control offspring, were examined for body and neurological development and subjected to a screening battery of behavioral tests, designed to model symptoms of psychiatric disorders. At least 12 mice were used for each test over the course of 16 weeks. PARTICIPANTS/MATERIALS, SETTING, METHODS: Embryos were subjected to a single BB at the 8-cell stage and then cultured in vitro until the blastocyst stage (BB group). Two control groups were created, one consisting of embryos cultured in vitro without any manipulation (in vitro control (IVC) group) and one of embryos developed entirely in vivo (in vivo group). Embryos from in vitro groups (BB and IVC) were transferred to pseudo-pregnant female mice at the blastocyst stage. Body growth parameters and developmental landmarks of the resulting offspring were observed during their entire lifespan. Furthermore, validated behavioral tests were used to assess early communicative functions, startle reflex, and anxiety- and depression-like behaviors. MAIN RESULTS AND THE ROLE OF CHANCE: We found that male mice derived from BB exhibited peculiar behavioral alterations and changes in body weight. BB-derived male mice showed increased body weight with respect to both controls as early as the second week of life. Adult males displayed decreased times of immobility in the tail suspension test (P < 0.05) and deficits in habituation to, and pre-pulse inhibition of, the startle reflex (P < 0.05). BB did not affect communicative skills and anxiety-like responses. LIMITATIONS, REASONS FOR CAUTION: Extrapolation of these results to humans requires caution as the culture protocols used in human clinics could be better established than in mice research. Furthermore species-specific neurodevelopmental features could be a source of differences between mice and humans in the effects of BB. WIDER IMPLICATIONS OF THE FINDINGS: Our data demonstrate that BB affects long-term programming of post-natal development and behavior in mice, suggesting that PGD procedures could be a risk factor for late-onset, neurodevelopmental and metabolic disease predisposition. Thus, in light of our observations, long-term follow-up in humans or other primates generated after BB is needed. STUDY FUNDING/COMPETING INTERESTS: This work was supported by the European Research Council (FP7/2007-2013)/Programme IDEAS GA no. 210103 to G.E.P. European Research Council - Programme FP7-KBBE-2012.1.3-04, GA no. 312097 Acronym: FECUND to G.E.P.; MIUR/CNR, Programme FIRB. GA n. B81J12002520001 Acronym: GenHome to P.L. The authors are participating in the COST action FA 1201 'Epiconcept' Epigenetic and Periconception Environment. No competing interests are declared.


Assuntos
Comportamento Animal , Peso Corporal , Desenvolvimento Embrionário , Diagnóstico Pré-Implantação/efeitos adversos , Animais , Fertilidade , Habituação Psicofisiológica , Masculino , Camundongos , Fatores de Risco
12.
Transl Psychiatry ; 4: e386, 2014 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-24780920

RESUMO

Advanced paternal age (APA) contributes to the risk of autism spectrum disorders (ASDs) in children. In this study, we used a mouse model to investigate the effects of APA on behavioral features related to autistic syndromes (that is, social deficits, communication impairments and stereotypic/repetitive behaviors). We also examined whether such effects are transmitted across generations. To do this, males aged 15 months (APA) and 4 months (control) were bred with 4-month-old females, and the resulting offspring (F1) and their progeny (F2; conceived by 4-month-old parents) were tested for the presence and severity of ASD-like behaviors. Our results indicate that APA resulted in offspring that displayed distinctive symptoms of ASD. We found that both F1 conceived from old fathers and F2 derived from old grandfathers displayed increased ultrasound vocalization (USV) activity, decreased sociability, increased grooming activity and increased anxiety-like responses. Moreover, such abnormalities were partially transmitted to the second generation of mice, having APA grandfathers. In conclusion, our study suggests that the risk of ASD could develop over generations, consistent with heritable mutations and/or epigenetic alterations associated with APA.


Assuntos
Comportamento Animal/fisiologia , Transtornos Globais do Desenvolvimento Infantil/etiologia , Idade Paterna , Fatores Etários , Animais , Transtornos Globais do Desenvolvimento Infantil/genética , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Distribuição Aleatória
13.
Acta Chir Belg ; 113(4): 254-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24224433

RESUMO

OBJECTIVES: Sleeve gastrectomy (SG) has been used as the first step of a staged malabsorptive procedure for high-risk patients. More recently SG was proposed as an stand alone procedure in the treatment of morbidly obese patients. The aim of this study is to analyze perioperative outcome of morbid obese patients after SG. METHODS: 301 patients, 201 women and 100 men, undergoing SG were retrospectively analyzed. SG was performed by 17 surgeons all member of the Club Coelio. The mean BMI was 44.7kg/m2 (27.4-70.3 kg/m2). 34 patients (11.3%) of our series had SG as revisional surgery. These revisional procedures consisted of 32 conversions from gastric banding, 1 conversion from vertical gastroplasty (VBG) and 1 from transoral endoscopic gastroplasty. Among the 32 patients that had revisional SG after a gastric banding, 13 bands were removed at least 3 months before the revisional SG and 19 bands were removed during the SG procedure. Endpoints were perioperative morbidity and mortality and potential risk factors for complications, mainly per or postoperative bleeding or leakage. RESULTS: Overall mortality was 0% and morbidity was 10.3%. Perioperative bleeding occurred in 10 patients (3.3%), leakage in 12 patients (4%) patients and stenosis in 3 patients (1%). The risk of leakage was significantly higher after revisional bariatric surgery and in case of gastric perforation during surgery (p = 0.0001). Previous gastric banding is also associated with a higher risk of postoperative bleeding (p = 0.0006). CONCLUSIONS: SG can be safely performed but patients and surgeons must be aware of a higher risk of postoperative complications when SG is proposed as a revisional surgery.


Assuntos
Gastroplastia/efeitos adversos , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/epidemiologia , Medição de Risco/métodos , Adulto , Idoso , Bélgica/epidemiologia , Índice de Massa Corporal , Feminino , Seguimentos , Gastroplastia/métodos , Gastroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade/tendências , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Tempo , Falha de Tratamento , Resultado do Tratamento , Adulto Jovem
14.
Trends Biotechnol ; 31(12): 688-95, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24169600

RESUMO

We review published data on cell/gamete lyophilization. Most studies have utilized the same established protocols for cryopreservation (storage in liquid nitrogen) as for cell lyophilization (dehydration of frozen samples by water sublimation). Surveying natural lyoprotectants, we suggest trehalose and late embryogenesis abundant (LEA) proteins as ideal candidates for the reversible desiccation of mammalian cells/gametes. We find that despite the numerous water subtraction techniques, scientists have relied almost exclusively on lyophilization. There is thus room for improvement in both medium formulation and water subtraction strategies for dry cell/gamete storage. We believe the development of dry processing protocols for use in biobanks of cells/gametes, at reduced cost and with minimal carbon footprint, is within our grasp.


Assuntos
Bancos de Espécimes Biológicos , Liofilização , Células Germinativas , Animais , Sobrevivência Celular , Mamíferos , Substâncias Protetoras , Trealose
15.
Res Vet Sci ; 93(2): 862-4, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22326660

RESUMO

A female domestic duck (Anas platyrhynchos domesticus) suddenly died with abdominal distension and a large multilobulated mass within the coelomic cavity was found. Histologically and immunohistochemically, a benign mature tridermic teratoma was diagnosed and epithelial structures, cartilage, bone, myxoid tissue, adipocytes, muscle cells, cystic spaces lined by squamous epithelium, feather follicles, melanocytes and variable neural and glial differentiation were recognized. By electron microscopy, desmosomes, keratin bundles, dense core neurosecretory granules, aberrant Z-line material and Luse bodies were found. To our knowledge, this is the first report of tridermic benign intracoelomic teratoma of a duck in which an extensive immunohistochemical and electron microscopic examination has been performed and in which a common neural and glial differentiation has been demonstrated.


Assuntos
Patos , Imuno-Histoquímica/veterinária , Doenças das Aves Domésticas/patologia , Teratoma/veterinária , Animais , Evolução Fatal , Feminino , Teratoma/patologia , Teratoma/ultraestrutura
17.
Theriogenology ; 76(2): 217-28, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21458046

RESUMO

Much emphasis is currently given to the use of Interspecific Somatic Cell Nuclear Transfer (ISCNT) as a potential salvage tool for endangered animals. In this short review we present a survey on all data published so far on ISCNT, including abstract communication in international meetings. From the analysis of these data it appears that the results obtained are very preliminary and often confusing on the real stage of the embryonic development obtained. Moreover, the acronym ISCNT is improperly used because in many reports the nuclei and oocyte donor are not within the same species, but belong to different order and sometimes taxa, therefore, we classified all the ISCNT reports by allocating cell and oocyte donors to their respective order/species/class. The efficiency of cloning is low in all species owing to incomplete nuclear reprogramming of differentiated cells under the current procedures. ISCNT, however, poses additional hurdles which are rarely addressed in previously published work, and on which we focus in this review: mt/genomic DNA compatibility; embryonic genome activation of the donor nucleus by the recipient oocyte; availability of suitable foster mothers for ISCNT embryos. All these issues are discussed here, and possible solutions for the successful application of somatic cell nuclear transfer to endangered animals are also put forth.


Assuntos
Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Técnicas de Transferência Nuclear/veterinária , Animais , Reprogramação Celular , DNA/genética , DNA Mitocondrial/genética , Desenvolvimento Embrionário , Feminino , Doação de Oócitos/veterinária , Gravidez , Especificidade da Espécie , Ativação Transcricional , Zigoto
18.
Vet Pathol ; 45(6): 865-80, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18984789

RESUMO

Cloning of cattle, sheep, and mice by somatic cell nuclear transfer (SCNT) can result in apparently healthy offspring, but the probability of a successful and complete pregnancy is less than 5%. Failures of SCNT pregnancy are associated with placental abnormalities, such as placentomegaly, reduced vascularisation, hypoplasia of trophoblastic epithelium, and altered basement membrane. The pathogenesis of these changes is poorly understood, but current evidence implicates aberrant reprogramming of donor nuclei by the recipient oocyte cytoplast, resulting in epigenetic modifications of key regulatory genes essential for normal placental development. The purpose of this review is to provide an overview of the anatomic pathology of abnormal placentae of SCNT clones and to summarize current knowledge concerning underlying pathogenetic mechanisms.


Assuntos
Bovinos , Transferência Embrionária/veterinária , Placenta/patologia , Complicações na Gravidez/veterinária , Ovinos , Animais , Clonagem de Organismos , Feminino , Camundongos , Gravidez , Complicações na Gravidez/patologia
19.
Reprod Domest Anim ; 43 Suppl 2: 417-22, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18638155

RESUMO

Lyophilization has been used since long time to preserve yeast and bacteria strains. Subsequently, a great deal of efforts has been dedicated to the preservation in a dry state of red blood cells and platelets. However, despite more than 30 years passed by, no significant progress has been achieved. Recently, it has been reported that freeze-dried mice spermatozoa were able to generate normal offspring following injection into the mature mice oocytes. In this work, we prompted to apply the lyophilization protocol developed for mice spermatozoa to sheep somatic cells (lymphocytes and granulosa cells). More than 350 enucleated sheep oocytes were injected with granulosa cells, and freeze dried using the protocol developed for mice sperm cells. Transplanted nuclei organized large pronuclei with fragmented DNA, but none of them entered the first mitosis. In the second part of the experiments, trehalose and EGTA were found to reduce significantly the extent of nuclear damage (65% and 55% intact nuclei in lymphocyte and granulosa cells, respectively) following freeze drying. Granulosa cells lyophilized with EGTA/trehalose and stored at room temperature for 3 years were used for nuclear transfer, and the injected oocytes were cultured in vitro for 7 days. Approximately 16% of the oocyte injected with freeze-dried cells developed into blastocysts. To conclude, we demonstrated for the first time that nucleated cells maintain genomic integrity after prolonged storage in a dry state, and we were able to achieve early embryonic development following injection of these cells into enucleated sheep oocytes.


Assuntos
Técnicas de Transferência Nuclear/veterinária , Oócitos/citologia , Ovinos/fisiologia , Injeções de Esperma Intracitoplásmicas/veterinária , Animais , Blastocisto/citologia , Blastocisto/fisiologia , Feminino , Liofilização/métodos , Liofilização/veterinária , Masculino , Camundongos , Microscopia Eletrônica de Varredura/veterinária , Oócitos/fisiologia , Oócitos/ultraestrutura , Injeções de Esperma Intracitoplásmicas/métodos , Espermatozoides/citologia , Espermatozoides/fisiologia , Espermatozoides/ultraestrutura
20.
Hum Reprod ; 23(10): 2331-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18614613

RESUMO

BACKGROUND: The process of implantation is mediated by various molecules, one of which is anandamide (AEA), a lipid signalling ligand belonging to the family of endocannabinoids. AEA exerts its effects on implantation by binding to the Type 1 Cannabinoid Receptor (CB1-R), expressed in both blastocysts and uterus. We wanted to know whether the endocannabinoid signalling system was present also in the sheep reproductive tract and which kind of effect(s) AEA had on the development of sheep blastocysts in vitro. METHODS: We analysed the expression and activity of the endocannabinoid system in sheep reproductive tracts and blastocysts. Hatched sheep blastocysts were then exposed to AEA and its effect(s) were determined by TUNEL assay and by measuring the rate of necrosis and 5-bromo-deoxyuridine incorporation. RESULTS: We show that the AEA signalling system is present in sheep and that high concentrations of AEA induce apoptosis and inhibit cell proliferation via a CB1-R-dependent mechanism. Indeed, AEA effects were blocked when sheep blastocysts were cultured in the presence of the CB1-R antagonist SR161417A. Moreover, AEA inhibition of cell proliferation was reversible, as arrested embryos resumed a normal growth rate upon AEA removal from the medium. CONCLUSIONS: Our results suggest that disturbed regulation of AEA signalling via CB1-R may be associated with pregnancy failure. AEA could lower the quality of blastocysts by inducing apoptosis and inhibiting cell proliferation, thus making them incompetent for implantation.


Assuntos
Apoptose/efeitos dos fármacos , Ácidos Araquidônicos/farmacologia , Blastocisto/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Alcamidas Poli-Insaturadas/farmacologia , Animais , Ácidos Araquidônicos/metabolismo , Moduladores de Receptores de Canabinoides/metabolismo , Endocanabinoides , Feminino , Marcação In Situ das Extremidades Cortadas , Necrose , Alcamidas Poli-Insaturadas/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Ovinos , Transdução de Sinais , Útero/metabolismo
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