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1.
Andrology ; 3(3): 611-25, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26013105

RESUMO

Testicular tissue cryopreservation offers the hope of preserved future fertility to pre-pubertal boys with cancer before exposition to gonadotoxic treatments. The objective of this study was to compare controlled slow freezing (CSF) with five vitrification techniques for cryopreservation of murine pre-pubertal testicular tissue and to evaluate the best protocol that could provide a successful completion of spermatogenesis after in vitro maturation. Testicular tissue from 24 mice at 6.5 days post-partum (dpp) was used to compare several vitrification protocols with one another, as well as with a CSF protocol. Toxicity test using additional 12 mice was performed for all cryopreservation solutions. Fresh tissue (FT) from six mice was used as a control. Once the optimal vitrification protocol was selected [the modified solid surface vitrification No. 1 (mSSV1 )], testes from 18 mice were cultured in vitro for 30 days with (i) fresh, (ii) slow-frozen/thawed and (iii) vitrified/warmed tissues. Testes from six mice at 36.5 dpp were used as controls. At day 30 of in vitro culture, germ cells of the seminiferous tubules showed a high ability to proliferate and elongated spermatids were observed after both freezing techniques, confirming the successful completion of in vitro spermatogenesis. However, after mSSV1 , the morphological alterations and the percentage of pyknotic seminiferous tubules were lower than CSF (4.67 ± 0.53 vs. 10.1 ± 1.12 and 22.7 ± 2.83% vs. 37.3 ± 4.24% respectively). Moreover, the number of flagellated spermatozoa produced per mg of tissue was higher for mSSV1 than for CSF (35 ± 3 vs. 9 ± 4 cells), with amounts of secreted testosterone during the culture close to those of FT. The mSSV1 protocol resulted in success rates better than CSF in maintaining testicular tissue structure, tubular morphology and tissue functions not solely for immediate frozen/thawed tissues but also after a long-term in vitro culture.


Assuntos
Criopreservação/métodos , Espermatogênese/fisiologia , Espermatozoides/citologia , Vitrificação , Animais , Proliferação de Células , Flagelos/fisiologia , Células Intersticiais do Testículo/citologia , Masculino , Camundongos , Preservação do Sêmen , Túbulos Seminíferos/citologia , Células de Sertoli/citologia , Testosterona/metabolismo
2.
Gynecol Obstet Fertil ; 41(9): 548-50, 2013 Sep.
Artigo em Francês | MEDLINE | ID: mdl-23972917

RESUMO

The survival of the young boy after cancer has considerably progressed in recent years due to the efficiency of chemo/radiotherapy against the tumor cells. However, this treatment causes adverse effects on healthy tissues, including fertility. Freezing testicular tissue before highly gonadotoxic treatment is a prerequisite for preserving fertility in prepubertal boys that do not produce sperm yet. But which strategy proposes to restore fertility from frozen-thawed testicular tissue? One potential solution would be to consider an in vitro maturation of spermatogonial stem cells. In this article we trace the chronological development of in vitro spermatogenesis that resulted in mouse sperm production in vitro and give an overview of new challenges for the future.


Assuntos
Células-Tronco Adultas/fisiologia , Preservação da Fertilidade/métodos , Espermatogênese , Animais , História do Século XX , História do Século XXI , Masculino , Camundongos , Técnicas de Cultura de Órgãos/história , Técnicas de Cultura de Órgãos/métodos
3.
Hum Reprod ; 28(6): 1468-79, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23539613

RESUMO

STUDY QUESTION: Is fertility preservation feasible after the onset of puberty in adolescents with Klinefelter syndrome (KS)? SUMMARY ANSWER: Fertility preservation counseling should be an integral part of the care of XXY adolescents. Frozen ejaculated or testicular spermatozoa and even frozen immature germ cells can give them the potential to conceive their genetic progeny. However, no biological or clinical parameters were predictive of mature or immature germ cell retrieval. WHAT IS KNOWN ALREADY: KS is the commonest sex chromosome disorder observed in azoospermic infertile males. Testicular sperm extraction success decreases with age and after testosterone therapy. Arguably, spermatozoa should be retrieved from KS males at the onset of puberty and before testosterone therapy to increase the chance of success. STUDY DESIGN, SIZE, DURATION: A retrospective study was performed in eight KS adolescents, aged between 15 and 17 years, who were referred for counseling about their future fertility to the center CECOS (Centre d'Etude et de Conservation des Oeufs et du Sperme humain) at Rouen University Hospital between October 2008 and December 2011. PARTICIPANTS/MATERIALS, SETTING, METHODS: The patients were first seen with their parents and then separately. It was proposed to them that they should provide a semen sample, if this was azoospermic, two other semen samples spaced by 3 months were collected. If azoospermia was confirmed, a bilateral testicular biopsy was proposed for sperm retrieval and testicular tissue preservation. Each adolescent met the psychologist before undergoing testicular biopsy. Paraffin-embedded testicular tissue was evaluated after staining with hematoxylin-eosin and saffron and immunostaining using vimentin, anti-Müllerian hormone, androgen receptor and MAGE-A4 antibodies. Sertoli cell maturity, germ cell identification and lamina propria alteration were assessed on seminiferous tubules. MAIN RESULTS AND THE ROLE OF CHANCE: KS adolescents were not deeply concerned about their future fertility and only became involved in the process of fertility preservation after at least three medical consultations. The parents agreed immediately that fertility preservation should be attempted. Seven non-mosaic XXY adolescents presented with azoospermia and one XXY/XY adolescent had oligozoospermia. Increased plasma levels of FSH and LH as well as bilateral testicular hypotrophy were observed in all patients. The XXY/XY adolescent banked four semen samples before testosterone replacement therapy. Two patients refused testicular biopsy. Five patients accepted a bilateral testicular biopsy. Spermatozoa were retrieved in one patient, elongated spermatids and spermatocytes I in a second patient. LIMITATIONS, REASONS FOR CAUTION: The number of patients enrolled in our study was low because the diagnosis of KS is only rarely made before or at the onset of puberty. Most XXY males are diagnosed in adulthood within the context of male infertility. WIDER IMPLICATIONS OF THE FINDINGS: Spermatozoa can be retrieved in semen sample and in testicular tissue of adolescent Klinefelter patients. Furthermore, the testis may also harbor spermatogonia and incompletely differentiated germ cells. However, the physician should discuss with the patient and his parents over a period of several months before collecting a semen sample and performing bilateral testicular biopsy. Fertility preservation might best be proposed to adolescent Klinefelter patients just after the onset of puberty when it is possible to collect a semen sample and when the patient is able to consider alternative options to achieve fatherhood and also to accept the failure of spermatozoa or immature germ cell retrieval.


Assuntos
Preservação da Fertilidade , Síndrome de Klinefelter/fisiopatologia , Recuperação Espermática , Adolescente , Fatores Etários , Azoospermia/complicações , Criopreservação , Aconselhamento Diretivo , Humanos , Síndrome de Klinefelter/complicações , Síndrome de Klinefelter/tratamento farmacológico , Masculino , Estudos Retrospectivos , Análise do Sêmen , Preservação do Sêmen , Espermatogênese , Testículo , Testosterona/efeitos adversos , Testosterona/uso terapêutico
4.
Gynecol Obstet Fertil ; 40(11): 671-4, 2012 Nov.
Artigo em Francês | MEDLINE | ID: mdl-23102576

RESUMO

Normal spermatogenesis results from a balance between process of cell proliferation, cell differentiation and apoptosis that concern somatic cells and germ cells. Dysfunction of spermatogenesis may be the result of constitutional or acquired abnormalities of spermatogonia stem cells or somatic cells. To overcome these problems, it seems necessary to implement preventive measures for germ stem cell preservation or substitute measures to replace them, the objective being to replicate in vivo or in vitro the process of spermatozoa production. This article will discuss the different experimental strategies for considering the in vivo or in vitro production of spermatozoa, outside the physiological process.


Assuntos
Espermátides/fisiologia , Espermatogênese/fisiologia , Espermatozoides/fisiologia , Animais , Apoptose , Diferenciação Celular , Proliferação de Células , Humanos , Infertilidade Masculina , Masculino , Células de Sertoli/fisiologia , Espermatozoides/anormalidades , Células-Tronco/fisiologia
5.
Int J Androl ; 35(4): 491-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22420485

RESUMO

With the motile sperm organelle morphology examination (MSOME), spermatozoa morphology may be assessed directly on motile spermatozoa at high magnification (up to 6600×). This procedure describes more precisely spermatozoa abnormalities, especially head vacuoles. However, no consensus has been established concerning normal or abnormal MSOME criteria. The aim of our study was to define MSOME vacuole criteria assessed objectively with a digital imaging system software to establish a potential relationship between conventional semen parameters. A total of 440 semen samples were obtained from males consulting in Rouen University Hospital Reproductive Biology Laboratory. Conventional semen analysis (volume, sperm concentration, progressive motility, vitality and morphology) and MSOME assessment {sperm head length, width and area as well as vacuole number, vacuole area and relative vacuole area to sperm head [RVA (%) = [vacuole area (µm(2))/head area (µm(2))] × 100)]} were performed for each semen sample. Among our 440 males, 109 presented normal conventional semen parameters and 331 abnormal ones. Sperm head vacuoles were significantly larger in abnormal semen samples (p < 0.0001). RVA was the most discriminative MSOME criterion between normal and abnormal semen samples according to ROC curves analysis, and was negatively correlated with poor sperm morphology (r = -0.53, p < 0.0001). We concluded to (i) the normal occurrence of vacuoles in sperm head whatever the normality or abnormality of semen parameters, (ii) the discriminative function of the RVA to distinguish semen samples with normal and abnormal parameters, and (iii) the strong correlation between high RVA and poor sperm morphology.


Assuntos
Infertilidade Masculina/diagnóstico , Análise do Sêmen/métodos , Cabeça do Espermatozoide/fisiologia , Motilidade dos Espermatozoides/fisiologia , Vacúolos/fisiologia , Adulto , Idoso , Diagnóstico por Imagem , Humanos , Masculino , Pessoa de Meia-Idade , Sêmen , Adulto Jovem
6.
Theriogenology ; 76(6): 981-90, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21664672

RESUMO

Fertility preservation has been included in the management of childhood cancer treatment. Cryopreservation of immature testicular tissue is the only available solution for pre-pubertal boys. Different freezing protocols have been developed in several species but without a clearly identified procedure. We tried to evaluate several protocols for cryopreservation of rat immature testicular tissue. Twelve different freezing protocols using different (i) cryoprotectant (dimethylsulphoxide [DMSO] or 1,2-propanediol [PROH]), (ii) cryoprotectant concentration (1.5M or 3M), (iii) equilibration time (30 or 60 min), (iv) equilibration temperature (4 °C or room temperature), (v) size of testicular fragment (7.5mg or 15 mg), (vi) package (straws or cryovials), were compared using cord morphological damage evaluation. A testicular tissue piece of 7.5mg cryopreserved in cryovial using 1.5M DMSO, an equilibration time of 30 min at 4 °C showed fewer morphological alterations than the other protocols tested. The selected freezing protocol was able to maintain rat immature testicular tissue architecture, functionality after testicular pieces organotypic culture, and could be proposed in a human application.


Assuntos
Criopreservação/veterinária , Ratos , Testículo/anatomia & histologia , Preservação de Tecido/veterinária , Animais , Proliferação de Células , Criopreservação/métodos , Crioprotetores , Dimetil Sulfóxido , Masculino , Técnicas de Cultura de Tecidos/veterinária , Preservação de Tecido/métodos
7.
Hum Reprod ; 26(1): 47-58, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21088015

RESUMO

BACKGROUND: Spermatozoa with large vacuoles (SLV) may have a negative impact on embryo development. The origin of these vacuoles is unknown. We evaluated acrosome and nucleus alterations in isolated SLV, versus unselected spermatozoa. METHODS: We studied 20 patients with teratozoospermia. Spermatozoa from the native semen sample and spermatozoa presenting a vacuole occupying >13.0% total head area, isolated under high magnification (×6600), were assessed. Confocal and transmission electron microscope evaluations were performed on SLV and native sperm, respectively. Acrosome morphology and DNA fragmentation were analysed using proacrosin immunolabelling (monoclonal antibody 4D4) and terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assay. Chromatin condensation was evaluated with aniline blue staining. Sperm aneuploidy was assessed using fluorescence in situ hybridization. RESULTS: SLV represented 38.0 ± 5.10% of motile spermatozoa obtained after gradient density centrifugation. Vacuoles were mainly in the anterior and median sperm head (45.7 ± 2.90 and 46.1 ± 3.00%, respectively). Abnormal acrosomes were increased in SLV compared with unselected spermatozoa (77.8 ± 2.49 versus 70.6 ± 2.62%; P = 0.014). Microscopic observations showed an exclusively nuclear localization of large vacuoles. Complete DNA fragmentation was higher in native spermatozoa (P < 0.0001) than SLV, while chromatin condensation was altered in SLV (P < 0.0001). Aneuploidy and diploidy rates were increased in SLV (P < 0.0001). CONCLUSIONS: Sperm vacuoles were exclusively nuclear. In our selected teratozoospermic population, aneuploidy and chromatin condensation defects were the main alterations observed in SLV. Based on results from this small sample of spermatozoa, we propose a global impairment of the spermatogenesis process as a common origin of the morphological alterations.


Assuntos
Acrossomo/ultraestrutura , Infertilidade Masculina/patologia , Análise do Sêmen/métodos , Espermatozoides/ultraestrutura , Vacúolos/ultraestrutura , Adulto , Aneuploidia , Núcleo Celular/ultraestrutura , Cromatina/ultraestrutura , Fragmentação do DNA , Desenvolvimento Embrionário , Humanos , Hibridização in Situ Fluorescente , Marcação In Situ das Extremidades Cortadas , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade
8.
J Androl ; 31(6): 617-30, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20203335

RESUMO

Numerous parameters have to be tested to identify optimal conditions for prepubertal testicular tissue banking. Our study evaluated 19 different cryopreservation conditions for immature testicular tissue using a rapid screening method. Immature mice testes were cryopreserved using either 1,2-propanediol (PROH) or dimethyl sulfoxide (DMSO) at a concentration of 0.75 or 1.5 M using a controlled slow-cooling rate protocol with (S+) or without seeding (S+). Equilibration was performed either at room temperature or at 4°C for 15 or 30 minutes. Seminiferous cord cryodamage was determined by scoring morphologic alterations. Cell proliferation ability was evaluated using a proliferating cell nuclear antigen (PCNA) antibody. Testes cryopreserved with optimal conditions were grafted into immunodeficient mice. The highest proportions of PCNA-positive nuclei and lowest morphologic alterations were observed with 1.5 M DMSO. Tissues were more altered with 0.75 M DMSO or PROH. Complete germ cell maturation was observed after allografting of testicular pieces previously frozen with 1.5 M DMSO, S+, 30 minutes. The 1.5 M DMSO, S+ or S+ protocol preserved prepubertal mice testicular tissue architecture and germ cell and Sertoli cell proliferation potential. Allografting of thawed testis fragments into immunodeficient mice confirmed that the 1.5 M DMSO, S+, 30 minutes protocol maintained testicular somatic and germ cell functions. Postthaw histologic evaluation and PCNA immunostaining are useful to rapidly test numerous freeze-thaw parameters. They may also be efficient tools to control human prepubertal frozen testis quality, within the context of a clinical application.


Assuntos
Criopreservação/métodos , Antígeno Nuclear de Célula em Proliferação/metabolismo , Testículo/citologia , Animais , Sobrevivência Celular , Crioprotetores/farmacologia , Dimetil Sulfóxido/administração & dosagem , Masculino , Camundongos , Camundongos Nus , Antígeno Nuclear de Célula em Proliferação/análise , Propilenoglicol/farmacologia , Testículo/efeitos dos fármacos , Testículo/fisiologia
9.
Gynecol Obstet Fertil ; 37(4): 313-20, 2009 Apr.
Artigo em Francês | MEDLINE | ID: mdl-19346148

RESUMO

OBJECTIVE: Despite technical progress in In Vitro Fertilisation (IVF) procedure, embryo implantation rate remains low. Assisted hatching has been proposed to facilitate natural embryo hatching and implantation. PATIENTS AND METHODS: Our study has evaluated whether laser assisted hatching improves implantation, pregnancy and live birth rates in different cases. We studied retrospectively 143 IVF cycles concerning more than 38 years old women, 166 IVF cycles after two previous implantation failures and 180 frozen-thawed embryo transfers. RESULTS: Population characteristics were comparable in hatched and control groups. Implantation, pregnancy and live birth rates in women more than 38 years old were comparable with or without assisted hatching. Concerning repeated implantation failures, even if implantation, pregnancy and live birth rates were higher in assisted hatching group (FIV or ICSI), the differences were not significant. After frozen-thawed embryo transfers, implantation rate was significantly better with assisted hatching (19.14% vs 8.84% [p=0.02]). DISCUSSION AND CONCLUSION: Assisted hatching improves embryo implantation rate after frozen-thawed embryo transfer.


Assuntos
Fertilização in vitro/métodos , Nascido Vivo , Adulto , Transferência Embrionária/métodos , Feminino , Humanos , Recém-Nascido , Indução da Ovulação/métodos , Gravidez , Técnicas de Reprodução Assistida/estatística & dados numéricos , Técnicas de Reprodução Assistida/tendências , Estudos Retrospectivos , Falha de Tratamento , Resultado do Tratamento
10.
Hum Reprod ; 23(1): 17-28, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17989070

RESUMO

BACKGROUND: Cryopreservation of immature testicular tissue could be considered as a major step in fertility preservation for young boys with cancer. In the present study, eight different freezing protocols were evaluated in immature mice testis. METHODS: Testis from six-day-old mice were frozen using either 1,2-propanediol (PROH) or dimethylsulphoxide (DMSO: D) at 1.5 M. Different cooling rate curves were tested: (i) controlled slow protocol with seeding (CS+) or (ii) without seeding (CS-), (iii) controlled rapid protocol and (iv) non-controlled protocol. Cryodamage of seminiferous cords was semi-quantitatively determined, establishing a scoring of alterations. Cell viability and apoptosis induction were assessed on testicular cell suspensions immediately after digestion (D0) and after a 20-h culture period (D1). Cells recovered after digestion of 100 mg tissue and the rate of living and non-apoptotic cells were quantified at D0 and D1. A long-term culture (9 days) of testis pieces was carried out for the protocol offering the best survival. Testosterone production, intratubular cell proliferation and tubule growth were assessed. RESULTS: DMSO produced optimal results in the different cooling rate curves tested when compared with PROH. Optimal results were obtained for the DCS- procedure (P < 0.05). Testosterone production, tubule growth and cell proliferation of post-thaw pieces were similar to fresh samples. CONCLUSIONS: Testis freezing with 1.5 M DMSO in a CS- procedure was found to maintain not only immature testicular tissue architecture, but also viability of testicular cells, endocrine and partial exocrine functions of the testis. Semi-quantitative evaluation of seminiferous cord cryodamage can be effectively used to rapidly screen optimal freezing conditions and as a possible quality control in a human application.


Assuntos
Animais Recém-Nascidos , Criopreservação , Testículo , Animais , Apoptose , Contagem de Células , Sobrevivência Celular , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos , Antígeno Nuclear de Célula em Proliferação/metabolismo , Testículo/anatomia & histologia , Testículo/citologia , Testículo/metabolismo , Testículo/fisiologia , Testosterona/biossíntese
11.
Hum Reprod ; 21(7): 1749-58, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16497695

RESUMO

BACKGROUND: In order to assess sperm alterations observed in some XYY males, we analysed the chromosome constitution as well as apoptosis expression in germ cells from two oligozoospermic males with high count of immature germ cells in their semen. METHODS: Sex chromosome number and distribution were assessed at pachytene stage by fluorescence in situ hybridization (FISH). Immature germ cells and spermatozoa were examined by FISH and TdT (terminal deoxynucleotidyl transferase)-mediated dUDP nick-end (TUNEL) assay, combined with immunocytochemistry using the proacrosin-specific monoclonal antibody (mAb 4D4). RESULTS: For patients 1 and 2, two Y chromosomes were present in respectively 60.0 and 39.6% of pachytenes. The three sex chromosomes were always in close proximity and partially or totally condensed in a sex body. XYY spermatocytes I escape the pachytene checkpoint and achieve meiosis. Nevertheless, nuclear division and/or cytokinesis were often impaired during meiosis leading to diploid (mainly 47,XYY cells) and tetraploid (94,XXYYYY) meiocytes. The presence of binucleated (23,Y)(24,XY) immature germ cells resulting from cytokinesis failure agree with a preferential segregation of the two Y chromosomes during meiosis I. In addition, 69.6% (patient 1) and 53.12% (patient 2) of post-reductional round germ cells were XY. However, high level of apoptotic round germ cells (94.9% for patient 1 and 93.3% for patient 2) was detected and may explain the moderate increase of hyperhaploid XY spermatozoa. Segregation errors also occurred in the XY cell line responsible for disomic 18 and X, as well as 46,XY diploid spermatozoa. CONCLUSIONS: Our data are in agreement with the persistence of the extra Y chromosome during meiosis in XYY oligozoospermic males responsible for spermatogenesis impairment and a probable elimination via apoptosis of most XYY germ cells not solely during but also after meiosis.


Assuntos
Apoptose/fisiologia , Cromossomos Humanos Y/ultraestrutura , Células Germinativas/citologia , Oligospermia/genética , Cariótipo XYY/genética , Adulto , Fragmentação do DNA , Humanos , Hibridização in Situ Fluorescente , Marcação In Situ das Extremidades Cortadas , Masculino , Meiose/fisiologia , Espermatozoides/ultraestrutura
12.
Gynecol Obstet Fertil ; 33(9): 615-9, 2005 Sep.
Artigo em Francês | MEDLINE | ID: mdl-16129643

RESUMO

An increased incidence of cancer is observed in the population of adolescents and young adults since thirty years. Major progress in cancer diagnosis and therapy is unfortunately associated to high degree of toxicity on gonad function. Cryopreservation of ovarian tissue is performed in girls and women before cancer treatment with high risk of infertility. Procedures for ejaculated or testicular extracted spermatozoa are well defined. However, for prepubertal boys or after ejaculated sperm collection failure, mature or immature testicular tissue banking should be proposed. Still, an optimal cryopreservation protocol is a prerequisite for clinical application and does not exist for the moment. Furthermore, the future applications of immature testicular tissue banking should be developed, not solely germ cell in vitro maturation but also autologous testicular tissue grafting.


Assuntos
Criopreservação , Neoplasias/terapia , Testículo , Animais , Humanos , Masculino , Puberdade , Espermatozoides/fisiologia , Testículo/crescimento & desenvolvimento , Testículo/transplante
13.
Gynecol Obstet Fertil ; 32(9): 771-8, 2004 Sep.
Artigo em Francês | MEDLINE | ID: mdl-15380761

RESUMO

Chromosome meiotic pairing during male meiosis is a major event for chromosome segregation during anaphase I and spermatogenesis normal process. Chromosome non-disjunctions responsible for aneuploidy in male gametes can be observed during the first and the second meiotic divisions. The analysis of sperm nuclei chromosome constitution is a major and indirect tool for assessing male meiotic non-disjunctions and the genesis of chromosomal abnormalities. This evaluation has been performed initially by the human sperm/hamster oocyte fusion assay and more recently by fluorescence in situ hybridisation (FISH). Therefore, male populations with increased risk of aneuploidy for their progeny could be identified before entering an in vitro fertilization procedure, and depending on the potential risk a preimplantation or prenatal genetic diagnosis could be performed. For males with constitutional chromosome abnormalities, a specific genetic counselling could also be proposed.


Assuntos
Aberrações Cromossômicas , Espermatozoides/ultraestrutura , Aneuploidia , Animais , Cricetinae , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Meiose , Interações Espermatozoide-Óvulo , Espermatozoides/fisiologia
14.
Theor Appl Genet ; 107(6): 1139-47, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12838393

RESUMO

Rice blast disease is a major constraint for rice breeding. Nevertheless, the genetic basis of resistance remains poorly understood for most rice varieties, and new resistance genes remain to be identified. We identified the resistance gene corresponding to the cloned avirulence gene ACE1 using pairs of isogenic strains of Magnaporthe grisea differing only by their ACE1 allele. This resistance gene was mapped on the short arm of rice chromosome 8 using progenies from the crosses IR64 (resistant) x Azucena (susceptible) and Azucena x Bala (resistant). The isogenic strains also permitted the detection of this resistance gene in several rice varieties, including the differential isogenic line C101LAC. Allelism tests permitted us to distinguish this gene from two other resistance genes [ Pi11 and Pi-29(t)] that are present on the short arm of chromosome 8. Segregation analysis in F(2) populations was in agreement with the existence of a single dominant gene, designated as Pi33. Finally, Pi33 was finely mapped between two molecular markers of the rice genetic map that are separated by a distance of 1.6 cM. Detection of Pi33 in different semi-dwarf indica varieties indicated that this gene could originate from either one or a few varieties.


Assuntos
Imunidade Inata/genética , Magnaporthe/genética , Oryza/genética , Doenças das Plantas , Mapeamento Cromossômico , Cromossomos de Plantas , Oryza/microbiologia , Oryza/fisiologia
15.
Int J Androl ; 26(4): 242-9, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12846800

RESUMO

The aim of this study was to determine the incidence of sex chromosome aneuploidy in spermatozoa of two males with a 47,XYY karyotype and one male with a 46,XY/47,XYY constitution. Spermatozoa obtained from two oligospermic patients and one volunteer semen donor were studied by multicolour fluorescence in situ hybridization. In the XY/XYY male, the frequencies of X-bearing to Y-bearing sperm were significantly different from the 1 : 1 expected ratio. Significantly increased frequencies were found in the mosaic and non-mosaic males for 24,XX and 24,YY sperm when compared with control donors. The number of 24,XY sperm was significantly different from the controls in the XYY males, but not in the mosaic male. The incidence of disomy 18 and the rate of diploidy also increased in the three patients. However, the mosaic male had the lowest cumulative rate of disomic and diploid spermatozoa when compared with the two XYY patients. Our data suggest that: (i) chromosome abnormalities observed in spermatozoa of the two XYY oligoasthenoteratospermic (OAT) males arise through segregation errors in XY germ cells rather than normal meiosis of XYY germ cells, (ii) mosaic XYY males with normal semen parameters have a lower risk of producing offspring with a sex chromosomal abnormality than OAT males with XYY karyotype.


Assuntos
Segregação de Cromossomos , Fertilidade/genética , Infertilidade Masculina/genética , Meiose/genética , Mosaicismo/genética , Cromossomos Sexuais/genética , Cariótipo XYY/genética , Adulto , Aneuploidia , Humanos , Hibridização in Situ Fluorescente , Masculino
16.
Psychosomatics ; 41(4): 289-93, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10906350

RESUMO

Constant observation (CO) is a technique in which continuous one-to-one monitoring is used to assure the safety and well-being of an individual patient or others. This study reviewed 115 patient charts in a tertiary-care hospital to determine the correlates and predictors of the financial cost of CO. The mean duration for CO was 13.9 days with a median of 7.5 days. The cost average was $3,415 per incident with a range of $144-$68,500. The median cost was $1,872. The most common diagnosis was organic mental syndrome. Significant predictors of CO were disorientation, psychiatric medication used, and absence of alcohol use.


Assuntos
Custos Hospitalares/estatística & dados numéricos , Transtornos Neurocognitivos/economia , Planejamento de Assistência ao Paciente/economia , Equipe de Assistência ao Paciente/economia , Segurança/economia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Análise Custo-Benefício , Feminino , Hospitais Gerais/economia , Humanos , Masculino , Pessoa de Meia-Idade , New York
17.
J Biol Chem ; 275(15): 11451-8, 2000 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-10753962

RESUMO

Primary structures of the N-glycans of two major pollen allergens (Lol p 11 and Ole e 1) and a major peanut allergen (Ara h 1) were determined. Ole e 1 and Ara h 1 carried high mannose and complex N-glycans, whereas Lol p 11 carried only the complex. The complex structures all had a beta(1,2)-xylose linked to the core mannose. Substitution of the proximal N-acetylglucosamine with an alpha(1, 3)-fucose was observed on Lol p 11 and a minor fraction of Ole e 1 but not on Ara h 1. To elucidate the structural basis for IgE recognition of plant N-glycans, radioallergosorbent test analysis with protease digests of the three allergens and a panel of glycoproteins with known N-glycan structures was performed. It was demonstrated that both alpha(1,3)-fucose and beta(1,2)-xylose are involved in IgE binding. Surprisingly, xylose-specific IgE antibodies that bound to Lol p 11 and bromelain did not recognize closely related xylose-containing structures on horseradish peroxidase, phytohemeagglutinin, Ole e 1, and Ara h 1. On Lol p 11 and bromelain, the core beta-mannose is substituted with just an alpha(1,6)-mannose. On the other xylose-containing N-glycans, an additional alpha(1,3)-mannose is present. These observations indicate that IgE binding to xylose is sterically hampered by the presence of an alpha(1,3)-antenna.


Assuntos
Alérgenos/metabolismo , Fucose/metabolismo , Imunoglobulina E/metabolismo , Proteínas de Plantas/metabolismo , Polissacarídeos/química , Xilose/metabolismo , Western Blotting , Reações Cruzadas , Glicosilação , Humanos , Imunoglobulina E/biossíntese , Polissacarídeos/imunologia
18.
Arch Otolaryngol Head Neck Surg ; 123(11): 1193-200, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9366699

RESUMO

OBJECTIVE: To compare the safety and efficacy of ofloxacin otic solution with those of Cortisporin otic solutions (neomycin sulfate, polymyxin B sulfate, and hydrocortisone) in otitis externa in adults and children. DESIGN: Two randomized, evaluator-blind, multicenter trials, 1 each in children and adults. SETTING: Twenty-three primary care and referral ambulatory care sites per trial. PATIENTS: A total of 314 adults (12 years and older) and 287 children (younger than 12 years). Of the total, data for 247 adults and 227 children were considered clinically evaluable (CE), and those for 98 children and 98 adults were microbiologically evaluable (ME). INTERVENTIONS: Ofloxacin (adults, 0.5 mL; children, 0.25 mL) twice daily or Cortisporin (adults, 0.2 mL; children, 0.15 mL) 4 times daily for 10 days. MAIN OUTCOME MEASURES: The CE subjects were cured if all signs and symptoms resolved at posttherapy (days 11-13) and test-of-cure (days 17-20) visits. The ME subjects had microbiological and clinical successes if they were cured and had microbiological eradication or presumed eradication. RESULTS: Cure was observed in 82% and 97% of CE adults and children treated with ofloxacin and 84% and 95% of CE adults and children treated with Cortisporin, respectively. The most common pathogens at the pretherapy visit were Pseudomonas aeruginosa, Staphylococcus aureus, and enteric bacilli. There were no statistically significant differences in clinical or microbiological and clinical cure or in the rates of adverse events between treatment groups. CONCLUSIONS: Ofloxacin given twice daily is as safe and effective as Cortisporin given 4 times daily for otitis externa. The bacteriological findings and treatment responses do not differ between adults and children.


Assuntos
Anti-Infecciosos/administração & dosagem , Ofloxacino/administração & dosagem , Otite Externa/tratamento farmacológico , Adulto , Criança , Pré-Escolar , Esquema de Medicação , Combinação de Medicamentos , Enterobacter cloacae/isolamento & purificação , Enterococcus faecalis/isolamento & purificação , Feminino , Humanos , Hidrocortisona/administração & dosagem , Klebsiella pneumoniae/isolamento & purificação , Masculino , Neomicina/administração & dosagem , Otite Externa/microbiologia , Polimixina B/administração & dosagem , Proteus mirabilis/isolamento & purificação , Pseudomonas aeruginosa/isolamento & purificação , Soluções , Staphylococcus aureus/isolamento & purificação , Resultado do Tratamento
20.
Gen Hosp Psychiatry ; 12(3): 166-9, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2335302

RESUMO

Compliance with treatment is an important concern in the management of patients with a wide array of medical disorders. A chart review of 20 hospitalized AIDS patients at one medical center was done to determine the degree of noncompliance in this extremely ill population. Ninety percent of AIDS patients declined some procedure or treatment, leading to a mean refusal rate of 19.7 refusals per 100 hospital days. Compared to a control population of male leukemics, the mean rate of refusal per hospital day among AIDS patients was over four times greater (p less than 0.05, Student's t-test, two-tailed). Reasons for noncompliance among hospitalized AIDS patients deserve further study.


Assuntos
Síndrome da Imunodeficiência Adquirida/psicologia , Cooperação do Paciente , Encaminhamento e Consulta , Sorodiagnóstico da AIDS/psicologia , Adulto , Homossexualidade/psicologia , Humanos , Leucemia/psicologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Abuso de Substâncias por Via Intravenosa/psicologia
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