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1.
Nature ; 559(7713): 227-231, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29995863

RESUMO

The quantum Hall effect in two-dimensional electron gases involves the flow of topologically protected dissipationless charge currents along the edges of a sample. Integer or fractional electrical conductance is associated with edge currents of electrons or quasiparticles with fractional charges, respectively. It has been predicted that quantum Hall phenomena can also be created by edge currents with a fundamentally different origin: the fractionalization of quantum spins. However, such quantization has not yet been observed. Here we report the observation of this type of quantization of the Hall effect in an insulating two-dimensional quantum magnet1, α-RuCl3, with a dominant Kitaev interaction (a bond-dependent Ising-type interaction) on a two-dimensional honeycomb lattice2-7. We find that the application of a magnetic field parallel to the sample destroys long-range magnetic order, leading to a field-induced quantum-spin-liquid ground state with substantial entanglement of local spins8-12. In the low-temperature regime of this state, the two-dimensional thermal Hall conductance reaches a quantum plateau as a function of the applied magnetic field and has a quantization value that is exactly half of the two-dimensional thermal Hall conductance of the integer quantum Hall effect. This half-integer quantization of the thermal Hall conductance in a bulk material is a signature of topologically protected chiral edge currents of charge-neutral Majorana fermions (particles that are their own antiparticles), which have half the degrees of freedom of conventional fermions13-16. These results demonstrate the fractionalization of spins into itinerant Majorana fermions and Z2 fluxes, which is predicted to occur in Kitaev quantum spin liquids1,3. Above a critical magnetic field, the quantization disappears and the thermal Hall conductance goes to zero rapidly, indicating a topological quantum phase transition between the states with and without chiral Majorana edge modes. Emergent Majorana fermions in a quantum magnet are expected to have a great impact on strongly correlated quantum matter, opening up the possibility of topological quantum computing at relatively high temperatures.

2.
Folia Morphol (Warsz) ; 77(4): 677-682, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29500894

RESUMO

BACKGROUND: Clinicians should understand that jugulocephalic vein (JCV) variants may be occasionally found. This study aims to classify JCV variants and obtain their frequency. MATERIALS AND METHODS: We investigated anatomical variants of the cephalic vein in 55 human cadavers during a gross anatomy course at our medical school. RESULTS: The percentage of JCVs that pass through the anterior part of the clavicle and anastomose to the jugular vein as per previous studies and our study was 2-5%. Five cases with anastomosis between the cephalic and external jugular veins that pass through the anterior part of the clavicle were found. The courses were classified into 1A, 1B, 2A, and 2B. Type 1 extends beyond the clavicle and anastomoses with the external jugular vein. Type 2 follows the same course as type 1, but anastomoses with the subclavian vein. Subtype A does not have a branch that anastomoses with the axillary vein, whereas subtype B does. We encountered two cases of type 1A and three of type 1B. CONCLUSIONS: Four anatomical variants of the cephalic vein around the clavicle were identified. Clinicians' knowledge of these variants is expected to decrease possible complications if venous access via the cephalic vein is needed.


Assuntos
Clavícula/irrigação sanguínea , Veias/anatomia & histologia , Variação Anatômica , Cadáver , Feminino , Humanos , Masculino
3.
Orthod Craniofac Res ; 20(1): 30-34, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28102013

RESUMO

OBJECTIVES: The aim of this study was to analyze MMP-1 transcript levels in periodontal tissues of rats that underwent orthodontic treatment using potassium diclofenac and dexamethasone at different stages of tooth movement. SETTING AND SAMPLE POPULATION: The sample comprised of ninety male Wistar rats. MATERIAL AND METHODS: A closed nickel-titanium coil spring was used to apply a force of 50 cN to move the maxillary right first molars mesially. One group received daily doses of 0.9% saline solution, the second group received daily doses of 5 mg/kg potassium diclofenac, and the third group received daily doses of 0.5 mg/kg dexamethasone. Tooth movement was observed on days 0, 1, 3, 7, and 14. MMP-1 transcript levels were evaluated by real-time polymerase chain reaction and the results were compared between groups by three-way ANOVA, with a significance level of 0.05. RESULTS: Transcript levels increased in groups that received the coil spring treatment on all days of the experiment. MMP-1 expression was found to be decreased in groups treated with potassium diclofenac and dexamethasone compared to that in the control group, on days 1, 3, 5, and 7. CONCLUSIONS: The application of orthodontic forces significantly increased MMP-1 transcript levels. The use of anti-inflammatory drugs may have an inhibitory effect on MMP-1 expression.


Assuntos
Anti-Inflamatórios/farmacologia , Dexametasona/farmacologia , Diclofenaco/farmacologia , Metaloproteinase 1 da Matriz/efeitos dos fármacos , Técnicas de Movimentação Dentária , Animais , Masculino , Metaloproteinase 1 da Matriz/metabolismo , Periodonto/efeitos dos fármacos , Periodonto/metabolismo , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos Wistar
4.
Folia Morphol (Warsz) ; 76(3): 408-413, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28281724

RESUMO

In a 94-year-old male cadaver, upon which routine dissection was being conducted, a rare variation was found in the gastrophrenic trunk (GPT), the common trunk of the left gastric artery (LGA), right inferior phrenic artery (RIPA), and left inferior phrenic artery (LIPA); the GPT arises from the abdominal aorta. A hepatosplenic trunk accompanied the variation. In this variation, the RIPA first branched from the GPT and then to the LIPA and LGA. Variations in the common trunk of the LIPA and RIPA in the GPT are common, but to our knowledge, a variation (separate inferior phrenic artery in the GPT) similar to our findings has not been previously reported. We discuss the incidence and developmental and clinical significance of this variation with a detailed review of the literature. Knowledge of such a case has important clinical significance for invasive and non-invasive arterial procedures. Therefore, different variations concerning the LGA and inferior phrenic artery should be considered during surgical and non-surgical evaluations.


Assuntos
Artéria Gástrica/patologia , Idoso de 80 Anos ou mais , Cadáver , Desenvolvimento Embrionário , Artéria Gástrica/embriologia , Humanos , Masculino
5.
Orthod Craniofac Res ; 19(3): 137-44, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26898697

RESUMO

OBJECTIVE: To evaluate the effect of organic gel solvents (70% acetone and 90% ethanol) and ultrasound in the removal of metallic brackets. MATERIALS AND METHODS: Metallic brackets were bonded with light-cured orthodontic composite (Transbond XT) in 120 human bicuspids and divided into 6 groups for the enamel etch-and-rinse adhesive system (XT) and 6 groups to self-etching system (SEPT) according to pretreatment to removal test: control, 70% acetone, 90% ethanol, ultrasound, 70% acetone+ultrasound, and 90% ethanol+ultrasound. The brackets were subjected to removal by shear testing and Adhesive Remnant Index (ARI) evaluation. Some specimens were prepared and its adhesive interface and etching ability observed by scanning electron microscopy (SEM). RESULTS: Only the factor 'ultrasound' and its interaction with 'adhesive' were detected as a source of variance, with the SEPT/ultrasound showing the lowest shear strength than the other groups. Regardless the factor 'ultrasound', XT showed a higher ARI than SEPT; however, when the solvents were used, no differences were detected between XT and SEPT. CONCLUSION: The organic solvents were not effective in reducing shear bond strength. The etch-and-rinse adhesive system showed a higher and more favorable ARI score than the self-etching primer. The behavior of the organic solvents on ARI showed to be better when associated with the self-etching primer. The ultrasound was effective in reducing the shear bond strength of the self-etching adhesive system but not in affecting the ARI of the adhesive systems.


Assuntos
Cimentos Dentários/química , Descolagem Dentária/métodos , Braquetes Ortodônticos , Solventes/química , Ultrassonografia de Intervenção/métodos , Acetona/química , Adesividade , Dente Pré-Molar , Pesquisa Comparativa da Efetividade , Esmalte Dentário/lesões , Etanol/química , Humanos , Teste de Materiais , Cimentos de Resina/química , Resistência ao Cisalhamento
6.
Orthod Craniofac Res ; 18(4): 242-50, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26333535

RESUMO

OBJECTIVES: To analyze the stress distribution on the PDL of the maxillary first molar in a mixed dentition Class III malocclusion, using a Hyrax-type appliance and maxillary protraction. SETTING AND SAMPLE POPULATION: A Class III malocclusion in the mixed dentition was reconstructed based on CBCT images. MATERIAL AND METHODS: The 3D FEM comprised the maxilla, alveolar bone, right first permanent molar teeth, and PDL and consisted of 1 133 497 nodes and 573 726 elements. Maxillary protraction force was applied to a hook positioned close to the deciduous canines with 600 g and at 15°, 30°, and 45° downward angles to the maxillary occlusal plane. RESULTS: Analysis was carried out from the top and buccal view of the sagittal plane. The magnitude of the stresses at 15°, 30°, and 45° of protraction angulation resulted in the highest stress magnitude being in the region between the distobuccal and palatal roots, as well as on the distal surface of the mesial root. The vector direction in this area showed traction and mesial movement. With 30° and 45° protraction angulations, the stress was located only between the distobuccal and palatal roots, and the vector direction was more extrusive at 15°. CONCLUSIONS: The suggested orthodontic movement is in the mesial direction with a small amount of extrusion with 15° angulation and greater extrusion with 30° and 45°.


Assuntos
Dentição Mista , Análise de Elementos Finitos , Má Oclusão Classe III de Angle/terapia , Maxila/fisiologia , Dente Molar/fisiologia , Ligamento Periodontal/fisiologia , Técnicas de Movimentação Dentária/métodos , Processo Alveolar/fisiologia , Fenômenos Biomecânicos , Criança , Tomografia Computadorizada de Feixe Cônico/métodos , Dente Canino/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Desenho de Aparelho Ortodôntico , Técnica de Expansão Palatina/instrumentação , Estresse Mecânico , Raiz Dentária/fisiologia , Dente Decíduo/fisiologia
7.
Folia Morphol (Warsz) ; 74(4): 544-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26620520

RESUMO

A rare variation was found in one of the two left renal veins in a 94-year-old male cadaver undergoing routine dissection. The characteristic findings in the cadaver included, in addition to the primary left renal vein, the presence of a posterior left renal vein draining to the left ascending lumbar vein without communicating with the inferior vena cava and other renal veins. Variations in the number and arrangement of the vessels terminating in the renal veins are common, but to our knowledge, variation similar to our findings has not been previously reported. This variation may represent an immature form of the complicated development of the renal vessels.

8.
Folia Morphol (Warsz) ; 81(2): 493-502, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33634835

RESUMO

BACKGROUND: The incidence of an elongated styloid process (SP) and average length and diameter of SP have not been reported using Japanese cadavers. Data on the female-to-male ratio of an elongated SP vary. We calculated the average length and diameter of SP in Japanese cadavers and compared SP lengths between sexes. MATERIALS AND METHODS: Twenty-seven sides (right and left of bodies) in males and 51 sides in females were analysed. Measurements were obtained from the inferior external acoustic meatus to the distal tip of the SP. SP diameters at the proximal base, midpoint, and distal tip were measured. SP > 30 mm was considered elongated. We used Welch's t-test for the statistical analysis. Fisher's exact two-tailed test was also performed to analyse the female-to-male elongation ratio. A p-value < 0.05 was considered statistically significant. RESULTS: Styloid process elongation prevalence was 29.5% in our sample. The average full length was 27.04 ± 7.88 mm overall; the average diameters were 5.41 ± 1.77 mm at the proximal base and 2.21 ± 1.22 mm at the distal tip. The average SP measurement was 26.81 ± 5.92 mm in males and 27.16 ± 8.79 mm in females (p = 0.74). The female-to-male ratio of SP elongation was 1:2 (p = 0.041). Females had longer full lengths of non-elongated SPs than males (p = 0.004). Males had wider diameters at the proximal base of elongated SPs than females (p = 0.017). CONCLUSIONS: The average length of SP was 27.04 mm in the Japanese population and about 30% of the Japanese presented SP ≥ 30 mm. Male had significantly higher rate than female among the SP ≥ 30 mm, and female had significantly longer SPs than male among the SP < 30 mm. Anatomically, the SP gets narrow as distally goes. Our anatomical findings would be beneficial to creating treatment plans, diagnosis, and surgery.


Assuntos
Ossificação Heterotópica , Osso Temporal , Cadáver , Feminino , Humanos , Japão , Masculino , Osso Temporal/anormalidades , Osso Temporal/anatomia & histologia
9.
Folia Morphol (Warsz) ; 80(2): 324-330, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32488854

RESUMO

BACKGROUND: A gonadal artery originates as a branch of the abdominal aorta and renal artery inferior to the level of origin of the renal arteries. Variations in multiple right testicular arteries (RTAs) arising from the abdominal aorta are common. We aimed to re-evaluate the unusual courses of gonadal arteries with a single common trunk in relation to the inferior vena cava and left renal vein and explain the developmental anatomy. MATERIALS AND METHODS: The observational cross-sectional study was performed on 54 Japanese adult cadavers (29 men and 25 women). We examined the literature and developed embryological hypotheses on the single common trunk of the gonadal artery. RESULTS: The gonadal artery, testicular artery, and ovarian artery arose from the abdominal aorta in 93.1%, 96.3%, and 89.6% of cases, respectively, and from the renal artery in 4.9%, 3.7%, and 6.3% of cases, respectively. We found two rare variations in the RTAs observed during the routine dissection of two male cadavers; in these two cases, a single common trunk of the RTAs originated from the abdominal aorta. A single common trunk was found in 3.7% of cadavers, 2.0% of sides, and 2.0% of arteries in the gonadal artery and in 6.9% of cadavers, 3.8% of sides, and 3.7% of arteries in the testicular artery. All cases of the single common trunk, including those in past reports, were observed only in men. CONCLUSIONS: Knowledge of the variations in RTAs has important clinical consequences for invasive and non-invasive arterial procedures. In addition, this variation provides a new interpretation of the embryology of the gonadal artery. Variations similar to our findings have not been previously reported. Therefore, different variations concerning the RTA should be considered during surgical and non-surgical evaluations.


Assuntos
Artéria Renal , Testículo , Adulto , Aorta Abdominal , Cadáver , Estudos Transversais , Feminino , Humanos , Masculino , Veias Renais
10.
Acta Radiol ; 49(1): 32-6, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17963080

RESUMO

We report a 78-year-old woman who presented with repeated tarry stools, and having lower duodenal variceal bleeding caused by portal hypertension. Endoscopic therapy had been attempted, but was impossible because the endoscope could not be inserted into the lower duodenum. Thus, the lower duodenal variceal bleeding was treated with balloon-occluded retrograde transvenous obliteration in combination with embolization using microcoils. Complete hemostasis was achieved without complications, and neither the recurrence of varices nor rebleeding has occurred for the last 3 years. A review of the English-language literature reveals only 11 such cases. The world literature is reviewed.


Assuntos
Oclusão com Balão/métodos , Varizes Esofágicas e Gástricas/terapia , Hemorragia Gastrointestinal/terapia , Radiologia Intervencionista/métodos , Idoso , Meios de Contraste/administração & dosagem , Duodeno/diagnóstico por imagem , Embolização Terapêutica/métodos , Varizes Esofágicas e Gástricas/etiologia , Etanolamina/administração & dosagem , Feminino , Seguimentos , Hemorragia Gastrointestinal/etiologia , Hepatite C/complicações , Humanos , Hipertensão Portal/complicações , Iopamidol/administração & dosagem , Cirrose Hepática/complicações , Tomografia Computadorizada por Raios X , Resultado do Tratamento
11.
Eur J Histochem ; 51(1): 43-51, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17548268

RESUMO

ATP-sensitive K+ (K(ATP)) channels in kidney are considered to play roles in regulating membrane potential during the change in intracellular ATP concentration. They are composed of channel subunits (Kir6.1, Kir6.2), which are members of the inwardly rectifying K+ channel family, and sulphonylurea receptors (SUR1, SUR2A and SUR2B), which belong to the ATP-binding cassette superfamily. In the present study, we have investigated the expression and localization of Kir6.1 in rat kidney with Western blot analysis, immunohistochemistry, in situ hybridization histochemistry, and immunoelectron microscopy. Western blot analysis showed that Kir6.1 was expressed in the mitochondria and microsome fractions of rat kidney and very weakly in the membrane fractions. Immunohistochemistry revealed that Kir6.1 was widely distributed in renal tubular epithelial cells, glomerular mesangial cells, and smooth muscles of blood vessels. In immunoelectron microscopy, Kir6.1 is mainly localized in the mitochondria, endoplasmic reticulum (ER), and very weakly in cell membranes. Thus, Kir6.1 is contained in the kidney and may be a candidate of mitochondrial K(ATP) channels.


Assuntos
Rim/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/biossíntese , Animais , Western Blotting , Imuno-Histoquímica , Hibridização In Situ , Canais KATP , Rim/ultraestrutura , Masculino , Microscopia Eletrônica , Microscopia Imunoeletrônica , Coelhos , Ratos , Ratos Wistar
12.
Forensic Sci Int ; 273: 80-87, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28249216

RESUMO

Dental uniqueness can be proven if no perfect match in pair-wise morphological comparisons of human dentitions is detected. Establishing these comparisons in a worldwide random population is practically unfeasible due to the need for a large and representative sample size. Sample stratification is an option to reduce sample size. The present study investigated the uniqueness of the human dentition in randomly selected subjects (Group 1), orthodontically treated patients (Group 2), twins (Group 3), and orthodontically treated twins (Group 4) in comparison with a threshold control sample of identical dentitions (Group 5). The samples consisted of digital cast files (DCF) obtained through extraoral 3D scanning. A total of 2.013 pair-wise morphological comparisons were performed (Group 1 n=110, Group 2 n=1.711, Group 3 n=172, Group 4 n=10, Group 5 n=10) with Geomagic Studio® (3D Systems®, Rock Hill, SC, USA) software package. Comparisons within groups were performed quantifying the morphological differences between DCF in Euclidean distances. Comparisons between groups were established applying One-way ANOVA. To ensure fair comparisons a post-hoc Power Analysis was performed. ROC analysis was applied to distinguish unique from non-unique dentures. Identical DCF were not detected within the experimental groups (from 1 to 4). The most similar DCF had Euclidian distance of 5.19mm in Group 1, 2.06mm in Group 2, 2.03mm in Group 3, and 1.88mm in Group 4. Groups 2 and 3 were statistically different from Group 5 (p<0.05). Statistically significant difference between Group 4 and 5 revealed to be possible including more pair-wise comparisons in both groups. The ROC analysis revealed sensitivity rate of 80% and specificity between 66.7% and 81.6%. Evidence to sustain the uniqueness of the human dentition in random and stratified populations was observed in the present study. Further studies testing the influence of the quantity of tooth material on morphological difference between dentitions and its impact on uniqueness remain necessary.


Assuntos
Dentição , Imageamento Tridimensional , Ortodontia Corretiva , Gêmeos , Feminino , Odontologia Legal , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Modelos Dentários , Curva ROC , Sensibilidade e Especificidade , Software
13.
Cancer Res ; 48(24 Pt 1): 7150-8, 1988 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-2903794

RESUMO

The localization of three carbohydrate antigens, Lex, Ley, and sialylated Lex-i, which are closely related to stage-specific embryonic antigen 1, in the lung of developing human embryos was investigated using specific monoclonal antibodies. In the 38-day-old embryo, when the primitive lung bud has appeared and developed into two lung sacs, only Ley antigen was specifically positive in the proliferating cells in the terminal portion of lung bud. In the 50-53-day-old embryos, the future bronchi were actively developing from the bronchial buds. At this stage, the Ley antigen was maximally expressed and the Lex antigen appeared in the bud cells. In the lung of the 12-week-old embryo, buds for the future bronchioles were lined by simple cuboidal epithelial cells, which were strongly positive for Lex antigen, weakly positive for Ley antigen, and still completely negative for sialylated Lex-i antigen. Sialylated Lex-i antigen finally appeared in 18-week-old embryos, in the cells of the terminal buds for the future alveoli. At this stage, the Lex and Ley antigens were already beginning to disappear and were only weakly positive in cells of terminal buds. At 20 weeks, only sialylated Lex-i antigen was weakly detected in the cells in the terminal buds; after 8 months, all three antigens were essentially not detected in the respiratory cells in most of the embryos examined in this study. Formation of bronchial glands was detected at 18 weeks, where the developing gland cells were specifically positive for sialylated Lex-i antigen. Ciliation of the bronchial epithelial cells started at 12 weeks and propagated thereafter. The ciliation was accompanied by the reappearance of Ley and Lex antigen in the epithelial cells. These findings collectively indicated that the three antigens all have a physiological significance as stage-specific developmental antigens of the human lung; those antigens were specifically present in the bud cells at each important step of the morphogenesis of the human lung, such as cells in the lung buds, bronchial buds, and terminal buds for the formation of the alveolus, and cells differentiating into bronchial gland cells. The three antigens gradually disappear in the later stage of development along with the maturation process of the lung. Stage-specific embryonic antigen 1 and related antigens are known to be associated with various human cancers, including lung cancers. We suggest that the expression of these antigens in the lung cancer cells is the result of the retrodifferentiation of the cancer cells to the stages of immature embryonic lung cells.


Assuntos
Glicolipídeos/análise , Neoplasias Pulmonares/análise , Pulmão/embriologia , Adenocarcinoma/análise , Anticorpos Monoclonais , Humanos , Antígenos do Grupo Sanguíneo de Lewis , Antígenos CD15
14.
Cancer Res ; 52(20): 5744-51, 1992 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-1394198

RESUMO

Expression of type 1 and type 2 chain carbohydrate antigens during the course of morphogenesis of human embryonic pancreas was investigated using specific monoclonal antibodies and compared with the carbohydrate antigen profiles of human pancreatic cancers. The type 2 chain antigens, such as stage-specific embryonic antigen 1 (Le(x)) and I-antigens, appeared much earlier than the type 1 chain antigens; the epithelial cells of primitive foregut were Le(x)+I-antigen- in the embryos at Carnegie stages 16-23, while the pancreatic primordial cells, which had differentiated from the Le(x)+ gut epithelial cells, were Le(x)-I-antigen+ at Carnegie stages 22-23. The type 1 chain antigens, such as Le(a), Le(b), Le(c), and their sialylated derivatives, were not expressed in any cells at these stages and appeared much later in the pancreas of the 10-12-week embryos, when the primitive pancreatic ductal cells in the primordia exhibited an extensive budding of the daughter cells. At this stage, Le(a) appeared and was expressed strongly in the epithelial cells of primitive pancreatic ducts as well as in the daughter cells that were destined to differentiate into future centroacinar cells; Le(b) was localized in the daughter cells which were to become future acinar cells; and Le(c) was specifically expressed in the daughter cells which were to form future Langerhans islets. With regard to the sialylated derivatives of Le(a), expression of the 2-3 sialyl Le(a) antigen was limited to the epithelial cells of the primitive pancreatic ducts, while the 2-6 sialyl Le(a) antigen was strongly expressed in the future centroacinar cells, which had differentiated from the corresponding daughter cells. Among these antigens, the Le(a) and 2-3 sialyl Le(a) antigens showed the highest incidence in human pancreatic cancer tissues. These results indicate that the expression of these carbohydrate antigens in embryonic pancreas is differentiation dependent and cell lineage specific and that most human pancreatic cancer cells mimic the carbohydrate antigen profile of the epithelial cells of the primitive pancreatic ducts in human embryos.


Assuntos
Amino Açúcares/imunologia , Antígenos Glicosídicos Associados a Tumores/metabolismo , Pâncreas/embriologia , Neoplasias Pancreáticas/imunologia , Polissacarídeos/imunologia , Adulto , Antígenos de Neoplasias/análise , Antígenos de Neoplasias/fisiologia , Antígenos Glicosídicos Associados a Tumores/análise , Antígenos Glicosídicos Associados a Tumores/fisiologia , Configuração de Carboidratos , Sequência de Carboidratos , Sistema Digestório/embriologia , Epitélio/embriologia , Idade Gestacional , Humanos , Dados de Sequência Molecular , Estadiamento de Neoplasias , Pâncreas/imunologia , Neoplasias Pancreáticas/química , Neoplasias Pancreáticas/patologia
15.
Cancer Res ; 50(23): 7603-11, 1990 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-1979246

RESUMO

The localization of two carbohydrate antigens, I and sialyl I antigens, in the lungs of developing human embryos was investigated using specific monoclonal antibodies and compared with the distribution patterns of the known embryonic antigen, stage-specific embryonic antigen-1 (Lex hapten). When the future bronchi were actively developing from the bronchial buds in the lungs of 50- to 53-day-old embryos, the immature bronchial bud cells were I-, Lex+, while the fully differentiated epithelial cells of the larger bronchus were I+, Lex-. When the bronchiolar bud cells matured into bronchiolar epithelial cells in the lung of a 12-week-old embryo, the immature bronchiolar bud cells were I-,Lex+, while the fully differentiated epithelial cells of the bronchioles were I+,Lex-. Sialylated forms of the antigens finally appeared in the lungs of 18-week-old embryos, when the terminal bud cells actively proliferated and underwent the differentiation process into epithelial cells of alveoli and alveolar ducts. The immature terminal bud cells at this stage were I-, sialyl I-, Lex+, sialyl Lex-i+, while the fully differentiated alveolar epithelial cells were I+, sialyl I+, Lex-, sialyl Lex-i-. After 8 months, the flattened mature alveolar epithelial cells were strongly positive for both I and sialyl I antigens, the strong expression of which continued after birth and even into the adult stage. These distribution patterns indicate that the I and sialyl I antigens are specific markers for the differentiated type cells in each stage of development, while Lex and related embryonic antigens were specific to the immature bud cells in every stage. The above-described differentiation-dependent expression patterns of these antigens seem to be reflected in the distribution of these antigens in human lung cancers, i.e., I and sialyl I antigens were expressed in lung cancer cells more weakly than in normal lung cells, while the Lex and sialyl Lex-i were expressed in cancer cells much more strongly than in normal lung cells. This was further reflected in the serum levels of these antigens in the patients with respiratory disorders. The distribution pattern of the serum levels of these antigens in patients with lung cancers showed sialyl Lex-i greater than sialyl I, indicating that these serum antigens originated from the lung cancer lesion where sialyl Lex-i is much more dominant than sialyl I antigen.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Adenocarcinoma/imunologia , Embrião de Mamíferos/imunologia , Desenvolvimento Embrionário e Fetal/imunologia , Antígenos de Histocompatibilidade Classe II/biossíntese , Antígenos CD15/biossíntese , Neoplasias Pulmonares/imunologia , Pulmão/imunologia , Adenocarcinoma/metabolismo , Anticorpos Monoclonais , Embrião de Mamíferos/metabolismo , Expressão Gênica , Humanos , Imuno-Histoquímica , Pulmão/metabolismo , Neoplasias Pulmonares/metabolismo
16.
J Clin Oncol ; 17(1): 277-83, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10458243

RESUMO

PURPOSE: To investigate whether the abnormalities observed on femoral marrow magnetic resonance images are related to the development of leukemia and survival of patients with myelodysplastic syndromes (MDS). PATIENTS AND METHODS: The findings on magnetic resonance images of the femoral marrow were evaluated over periods of 1 to 92 months (median, 18 months) in 42 consecutive adult patients with newly diagnosed MDS. Magnetic resonance images were obtained by the T1-weighted spin echo method and the short T1 inversion recovery technique. RESULTS: Magnetic resonance images showed that the femoral marrow patterns changed from fatty, faint, or nodular to scattered or uniform as the disease progressed. Development of acute myeloid leukemia was observed in only 13 patients whose marrow exhibited a scattered or uniform pattern. The overall survival of the 29 patients with a scattered or uniform marrow pattern was significantly shorter than that of the 13 patients with a fatty, faint, or nodular marrow pattern (10.7% v 73.3% at 7 years; P < .01). The period of leukemia-free survival was also significantly shorter in the patients with a scattered or uniform marrow pattern versus a fatty, faint, or nodular pattern (37.7% v 100% at 7 years; P < .01). CONCLUSION: Magnetic resonance images of the femoral marrow can provide valuable information for assessing the prognosis and determining the most appropriate management of patients with MDS.


Assuntos
Medula Óssea/patologia , Imageamento por Ressonância Magnética , Síndromes Mielodisplásicas/diagnóstico , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Refratária/diagnóstico , Anemia Refratária/mortalidade , Anemia Refratária/patologia , Anemia Refratária com Excesso de Blastos/diagnóstico , Anemia Refratária com Excesso de Blastos/mortalidade , Anemia Refratária com Excesso de Blastos/patologia , Anemia Sideroblástica/diagnóstico , Anemia Sideroblástica/mortalidade , Anemia Sideroblástica/patologia , Feminino , Fêmur , Humanos , Leucemia Mieloide/diagnóstico , Leucemia Mieloide/mortalidade , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/patologia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
17.
Diabetes ; 40(9): 1115-21, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1936618

RESUMO

We studied the effect of maternal hypoglycemia on skeletal growth in the offspring of nondiabetic and diabetic rats. Female Wistar rats were injected with streptozocin (30 mg/kg i.v.) 2-3 wk before mating, and diabetes was confirmed by an intraperitoneal glucose tolerance test. On postconception day 9.5 or 10.5, both control and diabetic dams received saline or Actrapid human insulin (400 mU/rat i.p.). Hypoglycemia (approximately 2.8 mM) was induced for 120 min in the insulin-treated mothers. Pregnancy was terminated on gestational day 20. Fetal bones and cartilage were double-stained with alizarin red S and alcian blue 8GS. Insulin-induced hypoglycemia caused delayed ossification in the fetuses of the control dams. The number of malformations, e.g., costal fusion waves, increased greatly. These effects were more striking in the fetuses of dams that had received insulin on day 10.5 rather than on day 9.5 of embryo development. This type of insulin-induced hypoglycemia further delayed ossification of the fetal bones in diabetic dams. The influence of maternal hypoglycemia on skeletal malformations and/or variations was greater in the fetuses of diabetic dams than in the fetuses of control dams. These data suggest that maternal hypoglycemia in early pregnancy has a striking effect on skeletal growth and malformations in fetuses. In addition, mild glucose intolerance in dams may amplify these hypoglycemic effects.


Assuntos
Osso e Ossos/anormalidades , Diabetes Mellitus Experimental/fisiopatologia , Hipoglicemia/fisiopatologia , Insulina/toxicidade , Gravidez em Diabéticas/fisiopatologia , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Feminino , Sangue Fetal/metabolismo , Reabsorção do Feto , Feto/efeitos dos fármacos , Hipoglicemia/induzido quimicamente , Insulina/sangue , Insulina/uso terapêutico , Insulina Regular de Porco , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Gravidez , Gravidez em Diabéticas/tratamento farmacológico , Ratos , Ratos Endogâmicos , Proteínas Recombinantes/uso terapêutico , Proteínas Recombinantes/toxicidade
18.
Diabetes ; 40(10): 1245-50, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1936588

RESUMO

Congenital malformations such as neural tube defects and a kinky or waved vertebral column were observed at higher incidence in embryos from nonobese diabetic (NOD) female mice with overt diabetes (NOD-D; 40.3%, P less than 0.005) or without overt diabetes (NOD-N; 8.4%, P less than 0.05) than in control Institute of Cancer Research (ICR) mouse embryos (1%) at day 13 of gestation. In vivo and in vitro preimplantation development of NOD-N, NOD-D, and ICR embryos did not differ in rate of development, size, or morphology. Embryos cultured from one-cell to early blastocyst stage were mutually transferred to uterine horns of pseudopregnant females between NOD-D and ICR mice and examined at day 13 of gestation. There were significant decreases in ratios of implantation and of viable embryos in ICR embryos transferred to NOD-D recipients (52%, P less than 0.001 and 14%, P less than 0.001, respectively) compared with those ratios in ICR embryos transferred to ICR uteri (79.2 and 56.2%) or those in NOD-D embryos transferred to ICR uteri (70.3 and 33.1%). Furthermore, 18 of 45 viable ICR embryos transferred to NOD-D dams had malformations, whereas there were no malformations in 73 viable ICR embryos transferred to ICR recipients, suggesting deleterious effects of maternal diabetic environment to embryos. On the other hand, 8 of 58 viable NOD-D embryos that were cultured in vitro and transferred to ICR uteri had malformations such as neural tube defects.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Diabetes Mellitus/fisiopatologia , Defeitos do Tubo Neural/etiologia , Obesidade/complicações , Gravidez em Diabéticas/fisiopatologia , Coluna Vertebral/anormalidades , Animais , Feminino , Camundongos , Camundongos Endogâmicos ICR , Camundongos Endogâmicos NOD , Defeitos do Tubo Neural/embriologia , Defeitos do Tubo Neural/genética , Gravidez
19.
Br J Radiol ; 78(933): 854-7, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16110112

RESUMO

We report a 34-year-old man with the complication of chylous ascites after retroperitoneal lymphadenectomy that was refractory to various conservative therapies. Because surgical treatment for chylous ascites was considered, lymphangiography was performed to identify the area of leakage of chyle, after which the chylous ascites spontaneously healed.


Assuntos
Ascite Quilosa/diagnóstico por imagem , Ascite Quilosa/etiologia , Linfografia , Adulto , Doença Crônica , Humanos , Excisão de Linfonodo/métodos , Masculino , Remissão Espontânea , Espaço Retroperitoneal , Tomografia Computadorizada por Raios X
20.
Pharmacogenetics ; 10(4): 335-41, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10862524

RESUMO

Previous studies have demonstrated that subjects with one or two A1 alleles of dopamine D2 receptor (DRD2) polymorphism at the Taq1 A locus have lower DRD2 density than those with no A1 allele. The present study aimed to examine whether the Taq1 A DRD2 genotypes are related to therapeutic response to nemonapride, a selective dopamine antagonist, in schizophrenic patients. The subjects were 25 acutely exacerbated schizophrenic inpatients who had received no medication for at least 1 month before the study. The fixed dose (18 mg/day) of nemonapride was administered to each patient for 3 weeks. The clinical status was prospectively monitored by the Brief Psychiatric Rating Scale (BPRS) before, and 3 weeks after, the treatment. The Taq1 A genotypes (A1 and A2 alleles) were determined by the polymerase chain reaction method. Three patients were homozygous for the A1 allele, 11 were heterozygous for the A1 and A2 alleles, and 11 were homozygous for the A2 allele. The patients with one or two A1 alleles (n = 14) showed significantly higher percentage improvement in total BPRS and positive symptoms than those with no A1 allele (n = 11) after 3-week treatment while the percentage improvement in other subgrouped symptoms (negative, anxiety-depression, excitement and cognitive symptoms) was similar between the two genotype groups. The present results suggest that the Taq1 A DRD2 polymorphism is related to early therapeutic response to nemonapride in schizophrenic patients, possibly by modifying the efficiency of DRD2 antagonism of the drug in the central nervous system.


Assuntos
Antipsicóticos/uso terapêutico , Benzamidas/uso terapêutico , Antagonistas de Dopamina/uso terapêutico , Polimorfismo Genético , Receptores de Dopamina D2/genética , Esquizofrenia/tratamento farmacológico , Taq Polimerase/genética , Adulto , Antipsicóticos/sangue , Benzamidas/sangue , Antagonistas de Dopamina/sangue , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
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