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1.
Ultrasound Obstet Gynecol ; 56(6): 934-943, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31975482

RESUMO

OBJECTIVES: To describe the clinical and ultrasound characteristics of adnexal torsion. METHODS: This was a retrospective study. From the operative records of the eight participating gynecological ultrasound centers, we identified patients with a surgically confirmed diagnosis of adnexal torsion, defined as surgical evidence of ovarian pedicle, paraovarian cyst and/or Fallopian tube twisted on its own axis, who had undergone preoperative ultrasound examination by an experienced examiner, between 2008 and 2018. Only cases with at least two available ultrasound images and/or videoclips (one grayscale and one with Doppler evaluation) were included. Clinical, ultrasound, surgical and histological information was retrieved from each patient's medical record and entered into an Excel file by the principal investigator at each center. In addition, two authors reviewed all available ultrasound images and videoclips of the twisted adnexa, with regard to the presence of four predefined ultrasound features reported to be characteristic of adnexal torsion: (1) ovarian stromal edema with or without peripherally displaced antral follicles, (2) the follicular ring sign, (3) the whirlpool sign and (4) absence of vascularization in the twisted organ. RESULTS: A total of 315 cases of adnexal torsion were identified. The median age of the patients was 30 (range, 1-88) years. Most patients were premenopausal (284/314; 90.4%) and presented with acute or subacute pelvic pain (305/315; 96.8%). The surgical approach was laparoscopic in 239/312 (76.6%) patients and conservative surgery (untwisting with or without excision of a lesion) was performed in 149/315 (47.3%) cases. According to the original ultrasound reports, the median largest diameter of the twisted organ was 83 (range, 30-349) mm. Free fluid in the pouch of Douglas was detected in 196/275 (71.3%) patients. Ovarian stromal edema with or without peripherally displaced antral follicles was reported in the original ultrasound report in 167/241 (69.3%) patients, the whirlpool sign in 178/226 (78.8%) patients, absent color Doppler signals in the twisted organ in 119/269 (44.2%) patients and the follicular ring sign in 51/134 (38.1%) patients. On retrospective review of images and videoclips, ovarian stromal edema with or without peripherally displaced antral follicles (201/254; 79.1%) and the whirlpool sign (139/153; 90.8%) were the most commonly detected features of adnexal torsion. CONCLUSION: Most patients with surgically confirmed adnexal torsion are of reproductive age and present with acute or subacute pain. Common ultrasound signs are an enlarged adnexa, the whirlpool sign, ovarian stromal edema with or without peripherally displaced antral follicles and free fluid in the pelvis. The follicular ring sign and absence of Doppler signals in the twisted organ are slightly less common signs. Recognizing ultrasound signs of adnexal torsion is important so that the correct treatment, i.e. surgery without delay, can be offered. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Anexos Uterinos/diagnóstico por imagem , Torção Ovariana/diagnóstico por imagem , Ultrassonografia Doppler/estatística & dados numéricos , Anexos Uterinos/anormalidades , Anexos Uterinos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Torção Ovariana/patologia , Dor Pélvica/diagnóstico por imagem , Dor Pélvica/etiologia , Dor Pélvica/patologia , Estudos Retrospectivos , Ultrassonografia Doppler/métodos , Anormalidades Urogenitais/complicações , Anormalidades Urogenitais/diagnóstico por imagem , Anormalidades Urogenitais/patologia , Útero/anormalidades , Útero/diagnóstico por imagem , Útero/patologia
2.
Mol Hum Reprod ; 25(4): 171-183, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30824926

RESUMO

In mouse and bovine sperm, GSK3 activity is inversely proportional to motility. Targeted disruption of the GSK3A gene in testis results in normal spermatogenesis, but mature sperm present a reduced motility, rendering male mice infertile. On the other hand, GSK3B testis-specific KO is fertile. Yet in human sperm, an isoform-specific correlation between GSK3A and sperm motility was never established. In order to analyze GSK3 function in human sperm motility, normospermic and asthenozoospermic samples from adult males were used to correlate GSK3 expression and activity levels with human sperm motility profiles. Moreover, testicular and sperm GSK3 interactomes were identified using a yeast two-hybrid screen and coimmunoprecipitation, respectively. An extensive in-silico analysis of the GSK3 interactome was performed. The results proved that inhibited GSK3A (serine phosphorylated) presents a significant strong positive correlation (r = 0.822, P = 0.023) with the percentage of progressive human sperm, whereas inhibited GSK3B is not significantly correlated with sperm motility (r = 0.577, P = 0.175). The importance of GSK3 in human sperm motility was further reinforced by in-silico analysis of the GSK3 interactome, which revealed a high level of involvement of GSK3 interactors in sperm motility-related functions. The limitation of techniques used for GSK3 interactome identification can be a drawback, since none completely mimics the physiological environment. Our findings prove that human sperm motility relies on isoform-specific functions of GSK3A within this cell. Given the reported relevance of GSK3 protein-protein interactions in sperm motility, we hypothesized that they stand as potential targets for male contraceptive strategies based on sperm motility modulation.


Assuntos
Astenozoospermia/genética , Fertilidade/genética , Quinase 3 da Glicogênio Sintase/genética , Processamento de Proteína Pós-Traducional , Motilidade dos Espermatozoides/genética , Espermatogênese/genética , Espermatozoides/enzimologia , Adulto , Animais , Astenozoospermia/enzimologia , Astenozoospermia/fisiopatologia , Bovinos , Expressão Gênica , Perfilação da Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Camundongos , Fosforilação , Ligação Proteica , Mapeamento de Interação de Proteínas , Espermatozoides/patologia , Testículo/enzimologia , Testículo/patologia
3.
Nanotechnology ; 29(17): 175401, 2018 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-29424701

RESUMO

The present study elucidates dispersive electron transport mediated by surface states in tin oxide (SnO2) nanoparticle-based dye sensitized solar cells (DSSCs). Transmission electron microscopic studies on SnO2 show a distribution of ∼10 nm particles exhibiting (111) crystal planes with inter-planar spacing of 0.28 nm. The dispersive transport, experienced by photo-generated charge carriers in the bulk of SnO2, is observed to be imposed by trapping and de-trapping processes via SnO2 surface states present close to the band edge. The DSSC exhibits 50% difference in performance observed between the forward (4%) and reverse (6%) scans due to the dispersive transport characteristics of the charge carriers in the bulk of the SnO2. The photo-generated charge carriers are captured and released by the SnO2 surface states that are close to the conduction band-edge resulting in a very significant variation; this is confirmed by the hysteresis observed in the forward and reverse scan current-voltage measurements under AM1.5 illumination. The hysteresis behavior assures that the charge carriers are accumulated in the bulk of electron acceptor due to the trapping, and released by de-trapping mediated by surface states observed during the forward and reverse scan measurements.

4.
Sci Rep ; 13(1): 12781, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550337

RESUMO

This contribution discusses surrogate models that emulate the solution field(s) in the entire simulation domain. The surrogate uses the most characteristic modes of the solution field(s), in combination with neural networks to emulate the coefficients of each mode. This type of surrogate is well known to rapidly emulate flow simulations, but rather new for simulations of elastoplastic solids. The surrogate avoids the iterative process of constructing and solving the linearized governing equations of rate-independent elastoplasticity, as necessary for direct numerical simulations or (hyper-)reduced-order-models. Instead, the new plastic variables are computed only once per increment, resulting in substantial time savings. The surrogate uses a recurrent neural network to treat the path dependency of rate-independent elastoplasticity within the neural network itself. Because only a few of these surrogates have been developed for elastoplastic simulations, their potential and limitations are not yet well studied. The aim of this contribution is to shed more light on their numerical capabilities in the context of elastoplasticity. Although more widely applicable, the investigation focuses on a representative volume element, because these surrogates have the ability to both emulate the macroscale stress-deformation relation (which drives the multiscale simulation), as well as to recover all microstructural quantities within each representative volume element.

5.
ACS Appl Mater Interfaces ; 15(12): 15290-15297, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36940415

RESUMO

Halide perovskite solar cells (PSCs) represent a low-cost and high-efficiency solar technology. However, most of the highly efficient PSCs need a noble electrode, such as Au, through thermal evaporation. It is reported that a sputtered Au electrode on a PSC could damage the organic hole transport layer (HTL) and the perovskite layer. Here, we report a simple, yet effective sputtered gold nanoparticle decorated carbon electrode to fabricate efficient and stable planar PSCs. The sputtered Au layer on the doctor-bladed coated carbon electrode can be directly applied to the perovskite semicells by mechanical stacking. By optimizing the gold thickness, a power conversion efficiency (PCE) of 16.87% was obtained for the composite electrode-based PSC, while the reference device recorded a PCE of 12.38%. The composite electrode-based device demonstrated 96% performance retention after being stored under humid conditions (50-60%) without encapsulation for ∼100 h. This demonstrates a promising pathway toward the commercialization of large-scale manufacturable sputtered electrodes for the PSC solar module.

6.
J Ultrasound Med ; 30(1): 37-45, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21193703

RESUMO

OBJECTIVES: The purpose of this study was to describe the sonographic appearance of the fetal anus and its usefulness in diagnosis of anal atresia. METHODS: An anomaly scan was performed in 13,150 patients over 8 years. Gestational ages ranged from 16 to 38 weeks. A tangential scan of the fetal perineum was performed. The anus was seen as a hypoechoic ring representing the wall of the anal canal with a central echogenic dot representing the lumen. This appearance was seen posterior to the external genitalia. If there was failure to see this appearance, a coronal scan of the fetal pelvis was done to look for the anal canal in contiguity with the rectum and to confirm its extension up to perineum. Failure to see these two features was considered diagnostic of anal atresia. RESULTS: On the basis of these criteria, anal atresia was diagnosed in 17 fetuses. Sixteen of these fetuses also had other associated anomalies. The appearance of the anus was useful for ruling out anal atresia in 2 fetuses with a dilated colon containing echogenic meconium balls. CONCLUSIONS: The anus is visible on a tangential scan of the fetal perineum. It can be seen routinely during an anomaly scan to diagnose or rule out anal atresia.


Assuntos
Ultrassonografia Pré-Natal/métodos , Canal Anal/diagnóstico por imagem , Canal Anal/embriologia , Malformações Anorretais , Anus Imperfurado/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Gravidez , Estudos Prospectivos
7.
Nanomaterials (Basel) ; 10(7)2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32650438

RESUMO

Solar thermal techniques provide a promising method for the direct conversion of solar energy to thermal energy for applications, such as water desalination. To effectively realize the optimal potential of solar thermal conversion, it is desirable to construct an assembly with localized heating. Specifically, photoactive semiconducting nanoparticles, when utilized as independent light absorbers, have successfully demonstrated the ability to increase solar vapor efficiency. Additionally, bio-based fibers have shown low thermal conductive photocorrosion. In this work, cellulose acetate (CA) fibers were loaded with cadmium selenide (CdSe) nanoparticles to be employed for solar thermal conversion and then subsequently evaluated for both their resulting morphology and conversion potential and efficiency. Electrospinning was employed to fabricate the CdSe-loaded CA fibers by adjusting the CA/CdSe ratio for increased solar conversion efficiency. The microstructural and chemical composition of the CdSe-loaded CA fibers were characterized. Additionally, the optical sunlight absorption performance was evaluated, and it was demonstrated that the CdSe nanoparticles-loaded CA fibers have the potential to significantly improve solar energy absorption. The photothermal conversion under 1 sun (100 mW/cm2) demonstrated that the CdSe nanoparticles could increase the temperature up to 43 °C. The CdSe-loaded CA fibers were shown as a feasible and promising hybrid material for achieving efficient solar thermal conversion.

8.
J Ultrasound Med ; 28(5): 657-62, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19389905

RESUMO

OBJECTIVE: The purpose of this series is to describe the sonographic features of isolated torsion of the fallopian tube. METHODS: Sonography was performed in 4 women with acute lower abdominal pain. RESULTS: The uterus and ovaries were normal in the 4 women. The ipsilateral fallopian tube was distended with fluid. A round mass was seen close to the tube. A sonographic whirlpool sign was seen on rocking movement of the probe over the mass. Ipsilateral torsion of the fallopian tube was confirmed at surgery in all of them. CONCLUSION: The sonographic whirlpool sign is the specific sign of tubal torsion.


Assuntos
Doenças das Tubas Uterinas/diagnóstico por imagem , Tubas Uterinas/diagnóstico por imagem , Anormalidade Torcional/diagnóstico por imagem , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Ultrassonografia
9.
Neuron ; 12(1): 167-77, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7507338

RESUMO

Neuronal membrane components that bind alpha-bungarotoxin with high affinity can increase intracellular levels of free calcium, demonstrating the components function as nicotinic receptors. Though such receptors often contain the alpha 7 gene product, which by itself can produce ionotropic receptors in Xenopus oocytes, numerous attempts have failed to demonstrate an ion channel function for the native receptors on neurons. Using rapid application of agonist, we show here that the native receptors are ligand-gated ion channels which are cation selective, prefer nicotine over acetylcholine, and rapidly desensitize. Much of the calcium increase caused in neurons by the receptors under physiological conditions appears to result from their depolarizing the membrane sufficiently to trigger calcium influx through voltage-gated channels.


Assuntos
Bungarotoxinas/farmacologia , Canais Iônicos/fisiologia , Neurônios/fisiologia , Nicotina/farmacologia , Receptores Colinérgicos/fisiologia , Animais , Bungarotoxinas/metabolismo , Cádmio/farmacologia , Células Cultivadas , Embrião de Galinha , Potenciais Evocados/efeitos dos fármacos , Feminino , Gânglios Simpáticos/fisiologia , Ativação do Canal Iônico , Canais Iônicos/efeitos dos fármacos , Cinética , Potenciais da Membrana/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Receptores Colinérgicos/biossíntese , Receptores Colinérgicos/metabolismo , Tetrodotoxina/farmacologia , Xenopus laevis
10.
Neuron ; 8(2): 353-62, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1310863

RESUMO

Many populations of vertebrate neurons have a membrane component that binds alpha-bungarotoxin and cholinergic ligands. Despite the abundance of this component and its similarities to nicotinic receptors, its function has remained controversial. Using a fluorescence assay, we show here that activation of the component elevates the intracellular concentration of free Ca2+, demonstrating a receptor function for the toxin-binding component. Whole-cell voltage-clamp and intracellular recordings did not detect a significant current resulting from receptor activation, possibly because the currents were small or the receptors rapidly desensitized. The rise in intracellular free Ca2+ caused by the receptor was prevented by Ca2+ channel blockers. This suggests a signaling cascade likely to have important regulatory consequences for the neuron.


Assuntos
Bungarotoxinas/metabolismo , Cálcio/metabolismo , Neurônios/metabolismo , Receptores Nicotínicos/metabolismo , Receptores Nicotínicos/fisiologia , Animais , Bungarotoxinas/farmacologia , Cádmio/farmacologia , Cálcio/análise , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/fisiologia , Células Cultivadas , Embrião de Galinha , Relação Dose-Resposta a Droga , Fluorescência , Neurônios/química , Neurônios/ultraestrutura , Níquel/farmacologia , Nicotina/metabolismo , Nicotina/farmacologia , Nifedipino/farmacologia , Tubocurarina/farmacologia
11.
Curr Med Chem ; 15(28): 2921-32, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19075644

RESUMO

The neuronal nicotinic receptor has gained considerable recognition as a target, not just for combating drug addiction but also for treating a number of illnesses ranging from neurodegenerative diseases to psychotic disorders like schizophrenia. This recognition has led to a burgeoning field examining the receptor at all levels. A class of nicotinic receptors that contains the alpha7 gene product, apparently as a homomer, illustrates this multidisciplinary approach. Here, we review recent progress in our understanding of this class of receptors based on data from molecular, structural, physiological and patho-physiological studies. These studies have set the stage for rational drug design to combat disorders of the central nervous system. The studies also exemplify the cautious approach needed in developing CNS therapies and the importance of physiology in tempering drug design.


Assuntos
Doenças do Sistema Nervoso Central/tratamento farmacológico , Química Farmacêutica/métodos , Desenho de Fármacos , Receptores Nicotínicos/química , Receptores Nicotínicos/genética , Receptores Nicotínicos/fisiologia , Sítio Alostérico , Animais , Sistema Enzimático do Citocromo P-450/química , Humanos , Ligantes , Modelos Biológicos , Modelos Químicos , Mutagênese Sítio-Dirigida , Ligação Proteica , Transdução de Sinais , Fumar , Receptor Nicotínico de Acetilcolina alfa7
12.
Oncogene ; 37(7): 839-846, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29059163

RESUMO

Cellular transformation and the accumulation of genomic instability are the two key events required for tumorigenesis. K-Ras (Kirsten-rat sarcoma viral oncogene homolog) is a prominent oncogene that has been proven to drive tumorigenesis. K-Ras also modulates numerous genetic regulatory mechanisms and forms a large tumorigenesis network. In this review, we track the genetic aspects of K-Ras signaling networks and assemble the sequence of cellular events that constitute the tumorigenesis process, such as regulation of K-Ras expression (which is influenced by miRNA, small nucleolar RNA and lncRNA), activation of K-Ras (mutations), generation of reactive oxygen species (ROS), induction of DNA damage and apoptosis, induction of DNA damage repair pathways and ROS detoxification systems, cellular transformation after apoptosis by the blebbishield emergency program and the accumulation of genomic/chromosomal instability that leads to tumorigenesis.


Assuntos
Carcinogênese/patologia , Genes ras , Instabilidade Genômica , Neoplasias/patologia , Animais , Carcinogênese/genética , Humanos , Neoplasias/genética , Transdução de Sinais
13.
FEBS Lett ; 581(27): 5213-9, 2007 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-17950289

RESUMO

Our previous study documented expression of a male-transmitted cytochrome c oxidase subunit II protein (MCOX2), with a C-terminus extension (MCOX2e), in unionoidean bivalve testes and sperm mitochondria. Here, we present evidence demonstrating that MCOX2 is seasonally expressed in testis, with a peak shortly before fertilization that is independent of sperm density. MCOX2 is localized to the inner and outer sperm mitochondrial membranes and the MCOX2 antibody's epitope is conserved across >65 million years of evolution. We also demonstrate the presence of male-transmitted mtDNA and season-specific MCOX2 spatial variation in ovaries. We hypothesize that MCOX2 plays a role in reproduction through gamete maturation, fertilization and/or embryogenesis.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/fisiologia , Óvulo/enzimologia , Espermatozoides/enzimologia , Unionidae/genética , Unionidae/fisiologia , Animais , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/química , Evolução Molecular , Feminino , Masculino , Microscopia Eletrônica , Reprodução/genética , Reprodução/fisiologia , Estações do Ano , Distribuição Tecidual
14.
Indian J Radiol Imaging ; 27(1): 70-72, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28515590

RESUMO

Here, we report a fetus with a rare aortic arch anomaly with left aortic arch and right ductus arteriosus, which has not been reported so far. In this condition, the aorta extends to the left of the trachea as in normal, while the ductus arteriosus extends to the right of the trachea and joins the descending aorta posterior to the trachea, with a cross-ribbon sign.

15.
Mol Genet Metab Rep ; 12: 2-7, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28243577

RESUMO

OBJECTIVES: This 109-week, nonrandomized, observational study of mucopolysaccharidosis II (MPS II) patients already enrolled in the Hunter Outcome Survey (HOS) (NCT00882921), assessed the long-term immunogenicity of idursulfase, and examined the effect of idursulfase-specific antibody generation on treatment safety (via infusion-related adverse events [IRAEs]) and pharmacodynamics (via urinary glycosaminoglycans [uGAGs]). METHODS: Male patients ≥ 5 years, enrolled in HOS regardless of idursulfase treatment status were eligible. Blood/urine samples for anti-idursulfase antibody testing and uGAG measurement were collected every 12 weeks. RESULTS: Due to difficulties in enrolling treatment-naïve patients, data collection was limited to 26 enrolled patients of 100 planned patients (aged 5.1-35.5 years) all of whom were non-naïve to treatment. Fifteen (58%) patients completed the study. There were 11/26 (42%) seropositive patients at baseline (Ab +), and 2/26 (8%) others developed intermittent seropositivity by Week 13. A total of 9/26 patients (35%) had ≥ 1 sample positive for neutralizing antibodies. Baseline uGAG levels were low due to prior idursulfase treatment and did not change appreciably thereafter. Ab + patients had persistently higher uGAG levels at entry and throughout the study than Ab - patients. Nine of 26 (34%) patients reported IRAEs. Ab + patients appeared to have a higher risk of developing IRAEs than Ab - patients. However, the relative risk was not statistically significant and decreased after adjustment for age. CONCLUSIONS: 50% of study patients developed idursulfase antibodies. Notably Ab + patients had persistently higher average uGAG levels. A clear association between IRAEs and antibodies was not established.

16.
FEBS Lett ; 580(3): 862-6, 2006 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-16414043

RESUMO

Analyses of unionoidean bivalve male-transmitted (M) mtDNA genomes revealed an approximately 555 bp 3' coding extension to cox2. An antibody was generated against this predicted C-terminus extension to determine if the unique cox2 protein is expressed. Western blot and immunohistochemistry analyses demonstrated that the protein was predominantly expressed in testes. Weak expression was detected in other male tissues but the protein was not detected in female tissues. This is the first report documenting the expression of a cox2 protein with a long C-terminus in animals. Its universal presence in unionoidean bivalve testes suggests a functional significance for the protein.


Assuntos
DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Regulação Enzimológica da Expressão Gênica/fisiologia , Testículo/enzimologia , Unionidae/enzimologia , Sequência de Aminoácidos , Animais , Complexo IV da Cadeia de Transporte de Elétrons/biossíntese , Masculino , Dados de Sequência Molecular , Processos de Determinação Sexual , Unionidae/genética
17.
J Natl Cancer Inst ; 69(2): 517-25, 1982 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6810006

RESUMO

The purpose of this study was to evaluate the gland-free mammary fat pad as a preferential site for transplantation of 7,12-dimethylbenz[a]anthracene (DMBA)-induced rat mammary tumors, since previous studies indicated their frequent failure to grow when transplanted in ectopic sites. Accordingly, samples from 14 primary mammary tumors (9 randomly selected and 5 ovarian-independent) were transplanted into the inguinal pairs of gland-free mammary fat pads of syngeneic female Lewis rats (9-12 wk of age). Although the percentage of takes was high (88%), the growth and morphogenetic capabilities of the transplants were strikingly different. Whereas transplants of ovarian-independent tumors consistently developed palpable carcinomas, transplants of all but 1 of the tumors selected at random (most of which were presumably ovarian-dependent) gave rise mainly to apparently normal ductal and hyperplastic outgrowths. The growth behavior of the transplants could not be correlated with the presence or absence in the tumors of mononuclear cells of the immune system. Unless the mammary fat pad selected against the growth of tumor cells, it seemed that the main alternative to tumor formation by the transplants was the proliferation of nontumorous outgrowths. These results draw attention to differences in the phenotypic stability of primary mammary tumors induced by DMBA and open up for further study the question of whether these differences reflect their cellular heterogeneity or their potential to undergo differentiation.


Assuntos
Glândulas Mamárias Animais , Neoplasias Mamárias Experimentais/patologia , 9,10-Dimetil-1,2-benzantraceno , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/patologia , Adenofibroma/induzido quimicamente , Adenofibroma/patologia , Animais , Divisão Celular/efeitos dos fármacos , Feminino , Hiperplasia , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Experimentais/induzido quimicamente , Transplante de Neoplasias , Ovário/fisiologia , Ratos , Ratos Endogâmicos Lew
18.
Mol Endocrinol ; 13(5): 705-17, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10319321

RESUMO

Agents that increase intracellular cAMP are potent stimulators of sperm motility. Anchoring inhibitor peptides, designed to disrupt the interaction of the cAMP-dependent protein kinase A (PKA) with A kinase-anchoring proteins (AKAPs), are potent inhibitors of sperm motility. These data suggest that PKA anchoring is a key biochemical mechanism controlling motility. We now report the isolation, identification, cloning, and characterization of AKAP110, the predominant AKAP detected in sperm lysates. AKAP110 cDNA was isolated and sequenced from mouse, bovine, and human testis libraries. Using truncated mutants, the RII-binding domain was identified. Alignment of the RII-binding domain on AKAP110 to those from other AKAPs reveals that AKAPs contain eight functionally conserved positions within an amphipathic helix structure that are responsible for RII interaction. Northern analysis of eight different tissues detected AKAP110 only in the testis, and in situ hybridization analysis detected AKAP110 only in round spermatids, suggesting that AKAP110 is a protein found only in male germ cells. Sperm cells contain both RI, located primarily in the acrosomal region of the head, and RII, located exclusively in the tail, regulatory subunits of PKA. Immunocytochemical analysis detected AKAP110 in the acrosomal region of the sperm head and along the entire length of the principal piece. These data suggest that AKAP110 shares compartments with both RI and RII isoforms of PKA and may function as a regulator of both motility- and head-associated functions such as capacitation and the acrosome reaction.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas/genética , Proteínas/metabolismo , Proteínas de Plasma Seminal , Espermatozoides/fisiologia , Proteínas de Ancoragem à Quinase A , Sequência de Aminoácidos , Animais , Sítios de Ligação , Bovinos , Clonagem Molecular , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Hibridização In Situ , Masculino , Camundongos , Dados de Sequência Molecular , Especificidade de Órgãos , Proteínas/isolamento & purificação , RNA Mensageiro/metabolismo , Análise de Sequência , Homologia de Sequência de Aminoácidos , Motilidade dos Espermatozoides , Frações Subcelulares , Testículo/fisiologia
19.
Cell Calcium ; 10(4): 241-53, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2776189

RESUMO

Internal calcium levels of sperm loaded with Quin-2 in the absence or presence of exogenous calcium were 63 +/- 5 and 189 +/- 19 nM, respectively. These values were similar to those determined by Fura-2. Surprisingly, however, dye loaded sperm depleted of internal calcium did not take up calcium from the medium into the cytoplasm upon re-addition of this ion. Uptake was rapid and maximal, however, if these cells were exposed to the calcium ionophores A23187 or ionomycin. Increasing [Quin-2]i progressively lowered [Ca2+]i in spite of the presence of exogenous calcium during dye loading. This anomaly was not due to interference of the fluorophores with calcium uptake, since exogenous 45Ca2+ was taken up at the same rate and to the same extent by control and fluorophore loaded sperm. This 45Ca2+ uptake was mitochondrial and energy dependent. Also, inhibition of mitochondrial calcium accumulation during dye loading lowered [Ca2+]i to values similar to those observed for calcium depleted sperm. These results suggest an extreme impermeability of the sperm plasma membrane to direct calcium entry into the cytoplasm while substantial amounts of calcium entry occurs into the sperm mitochondria.


Assuntos
Aminoquinolinas , Benzofuranos , Cálcio/metabolismo , Fura-2/análogos & derivados , Espermatozoides/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Transporte Biológico , Bovinos , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular , Citoplasma/metabolismo , Ionóforos/farmacologia , Masculino , Mitocôndrias/metabolismo , Motilidade dos Espermatozoides
20.
J Clin Endocrinol Metab ; 79(2): 568-70, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7913935

RESUMO

Obesity frequently clusters with hypertension, hyperlipidemia, non-insulin-dependent diabetes mellitus, and ischemic heart disease with hyperinsulinemia as syndrome X. Although central obesity has been recognized to have a strong genetic component, few candidate genes have been studied in this disorder. After a recently described association between the apolipoprotein-D (Apo-D) gene polymorphism and non-insulin-dependent diabetes mellitus by our group, we have now looked at a TaqI polymorphism of the Apo-D gene in two other components of syndrome X, namely obesity and hyperinsulinemia. Apo-D genotype differences were found between obese subjects (n = 57) and slim controls (n = 57; P = 0.006). Furthermore, in the obese group an association was found between the Apo-D genotype and fasting insulin (P < 0.001). Preliminary evidence, therefore, suggests that the TaqI Apo-D polymorphism can be used as a genetic marker for obesity and several components of syndrome X.


Assuntos
Apolipoproteínas/genética , Marcadores Genéticos , Insulina/sangue , Obesidade/genética , Polimorfismo de Fragmento de Restrição , Adulto , Apolipoproteínas D , Índice de Massa Corporal , Desoxirribonucleases de Sítio Específico do Tipo II , Feminino , Heterozigoto , Homozigoto , Humanos , Masculino , Angina Microvascular/genética , Pessoa de Meia-Idade
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